Open access peer-reviewed chapter

The Use of Molecular Pathway Inhibitors in the Treatment of Osteosarcoma

Written By

Adel Mahjoub, Jared A. Crasto, Jonathan Mandell, Mitchell S. Fourman, Rashmi Agarwal and Kurt R. Weiss

Reviewed: 26 January 2017 Published: 26 April 2017

DOI: 10.5772/67627

From the Edited Volume

Osteosarcoma - Biology, Behavior and Mechanisms

Edited by Kanya Honoki and Kurt Richard Weiss

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Abstract

Presently, the 5-year survival rate for metastatic osteosarcoma remains low despite advances in chemotherapeutics and neoadjuvant therapy. A majority of the morbidity and nearly all of the mortality in osteosarcoma rely not in the primary disease but in the metastatic disease. The pursuit of novel molecular therapies is attractive due to their targeted ability to combat metastasis. Unlike traditional chemotherapy agents, which work by targeting rapidly dividing cells, targeted therapies may spare normal cells and decrease the adverse effects of chemotherapy by targeting specific pathways. Here, we discuss key molecular pathways in osteosarcoma and their ability to be modulated for the goal of eradication of primary and metastatic disease. We focus specifically on the aldehyde dehydrogenase (ALDH), epidermal growth factor receptor (EGFR), and insulin-like growth factor-1 receptor (IGF-1R) pathways.

Keywords

  • osteosarcoma
  • molecular inhibition
  • metastasis
  • ALDH
  • EGFR
  • IGF-1R

1. Introduction

Prior to the use of chemotherapeutics, the 5-year survival rate of osteosarcoma (OS) was approximately 20% [1]. Despite new surgical techniques and the adoption of neoadjuvant therapy, patients diagnosed with nonmetastatic OS have a 65.8% 10-year survival rate, while those diagnosed with metastatic disease have a 15–30% 5-year survival rate [2]. These statistics have not improved in a generation. This stagnation may reflect recurrent disease as well as the intrinsic resistance of OS to chemotherapy.

The pursuit of targeted molecular therapies to treat OS has increased in popularity over the past decade. The inhibition of specific molecular pathways critical to OS metabolism may decrease its metastatic potential, slow its rate of growth, and potentially eliminate the disease altogether. Unlike chemotherapeutics, which act on all rapidly dividing cells, targeted therapies may be mechanistically independent in their efficacy. By specifically targeting OS cells, we may save normal cells and decrease the risk of adverse clinical side effects [3].

Here, we examine the inhibition of specific molecular targets that are critical to the biologic pathways of OS, but may spare other critical organ systems from damage.

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2. Aldehyde dehydrogenase (ALDH)

Aldehyde dehydrogenases (ALDHs) are a superfamily of nicotinamide adenine dinucleotide phosphate (NADP+)-dependent tetrameric enzymes that participate in aldehyde metabolism via catalysis of exogenous and endogenous aldehydes into their corresponding carboxylic acids and the cell’s resistance to oxidative stress [47]. Inhibition of ALDH can lead to a build-up of aldehydes that can lead to toxic side-effects, which include enzyme inactivation, DNA damage, impairment of cellular homeostasis, and cell death by forming adducts with various cellular targets [4, 8, 9].

Cancer stem cells (CSCs) comprise a small, distinct subpopulation of cancer cells that demonstrate robust self-renewal properties, enhanced differentiation capacity, the ability to propagate tumor growth, and increased resistance to chemotherapeutic drugs. ALDHs have been identified in numerous studies as elevated in highly malignant tumors and in CSCs [4, 1012]. ALDHs exert their effects through cellular processes such as target gene expression, protein translation, signal transduction, and antioxidative mechanisms. ALDH has, therefore, been implicated as a potential CSC marker. Cells found to be high in ALDH have demonstrated enhanced tumorigenicity in multiple cancers [7].

Elevated ALDH levels have been associated with poor survival in patients with breast and ovarian cancers [13, 14]. ALDH expression also appears to be linked with metastatic potential. Semisolid matrigel matrix invasion assays showed a correlation between ALDH levels and increased invasiveness when comparing two murine OS cell lines [7]. OS cells treated with disulfiram, an ALDH-inhibitor, show reduced ALDH expression and altered cellular morphology, with fewer invadopodia and greater shape uniformity [6, 15, 16].

2.1. Pathophysiology

Reactive oxygen species (ROS) are a natural by-product of aerobic metabolism and can lead to DNA damage, protein degeneration, and lipid membrane destruction. Cancer cells often generate abnormally high levels of ROS because of the aberrant metabolism and protein translation typical of diseased cells [17]. ALDHs play a vital role in clearing ROS and reducing the oxidative stress caused by ultraviolet radiation and chemotherapeutic agents. Cells that have high levels of ALDH expression have consistently lower ROS than those incapable of such expression [1820].

CSCs have relatively low levels of ROS, which may be because of elevated antioxidant enzyme levels [6, 21, 22]. The protective effects of ALDH for CSCs may also include the inhibition of downstream apoptosis-related pathways [18, 23, 24]. ALDH-positive CSCs have also demonstrated resistance to myriad chemotherapeutic agents such as anthracyclines and taxanes [25, 26], two classes of drugs commonly used in OS treatment. ALDH-positive cancer cells develop this drug resistance in part because of their increased ability to metabolize certain drugs into their nontoxic byproducts [27]. Once tumors are treated with chemotherapy or radiotherapy, the levels of CSCs with high ALDH expression tend to increase, increasing the cells’ abilities to become drug-resistant [25, 28].

Retinoic acid (RA) signaling plays a pivotal role both in embryonic [29] and tumor cells [30]. This pathway in fact exerts an antitumor effect. This is due to activation of a series of cellular genetic programs that modulate cell differentiation, apoptosis, and growth involved in the classical RA pathway [4, 31] (Figure 1 ). In this pathway, retinol is absorbed by cells, oxidized to retinal, and then oxidized to RA by ALDH. RA then enters the nucleus and can induce the transcriptional activity of downstream effectors through activation of heterodimers of the RA receptor and retinoic X receptors. RA binds its nuclear receptors and activates gene expression that affects loss of CSC markers, differentiation, cell cycle arrest, and morphology [32, 33]. The upregulation of these receptors generates a positive feedback loop for RA signaling. ALDH serves a paradoxical role in the RA pathway, by inducing differentiation of CSCs. The overall effect of this is antitumor, and thus exploiting this pathway is the goal for certain therapeutics.

Figure 1.

Potential retinoic acid-mediated signaling pathway in CSCs. Retinol (vitamin A) absorbed by cells is oxidized to retinal by retinol dehydrogenases. Retinal is oxidized to retinoic acid by ALDH enzymes. The metabolized product retinoic acid includes ATRA, 9-cis retinoic acid, and 13-cis retinoic acid, entering the nucleus and associated with RARα. In the classical pathway, retinoic acid binds to dimers of RARα and RXRs to induce the expression of its downstream target genes including RARβ. In the solid tumor type, RARβ promoter is methylated and/or the histones are significantly deacetylated, leading to low expression. In the nonclassical pathway, retinoic acid binds to dimers of RXRs and PPARβ/δ to induce the expression of its downstream target genes including PDK-1/Akt. In cells expressing ERα, retinoic acid can bind to dimers of RXRs and ERα as well as induce the expression of c-MYC and cyclin D1. Retinoic acid which extra-nuclearly binds with RARα can also induce the expression of c-MYC and cyclin D1 through the PI3K/Akt signaling pathway.

2.2. Therapeutic applications

Disulfiram (DSF) has been shown to enhance the cytotoxicity of several anticancer drugs, as well as radiotherapy, which early on indicated its potential role as either a novel chemotherapeutic agent or a sensitizer for other treatments [34]. Theories of its mechanism include the induction of oxidative stress and inhibition of proteasome activity through c-Jun N-terminal kinase (JNK), NF-ĸB, and PI3K pathways [3538].

In metastatic OS, the phenomenon of CSCs plays a large role in the ability of the disease to withstand a great amount of stress and remain invasive. ALDH is considered not only a surrogate marker for these cells but also a functionally important target [39]. The beauty of ALDH serving both roles is that the effects of DSF can be targeted to tumor cells exclusively due to their high ALDH content and additionally exert its antitumor effects. As described above, ALDH serves a pivotal role in reducing ROS to protect CSCs from oxidative stress and subsequent intracellular destruction. DSF as an inhibitor of this process has been shown to make the cancer cells more susceptible to oxidative stress and subsequently to improve survival in many cancer patients [40, 41].

DSF has also demonstrated efficacy in defeating the invasive nature of cancer by inhibiting matrix metalloproteinases (MMPs). In metastatic cancer physiology, the degradation of the extracellular matrix allows for primary tumor metastasis and distal site invasion. MMPs facilitate this process and are known to be closely associated with tumor growth and metastasis. In one study, nontoxic ranges of DSF successfully suppressed MMP-2 and MMP-9 activity and expression, producing a near complete growth inhibition at a 10 μM concentration of DSF [42].

Various studies have demonstrated that the cytotoxicity of DSF is copper dependent [38, 43, 44]. Copper plays an essential role in redox reactions and triggers generation of ROS in both normal and tumor cells [37, 44]. As a bivalent metal ion chelator, DSF forms a complex with copper and allows for Ctrl-transporter-independent transport of copper into tumor cells [43, 45]. For this reason, the DSF-copper complex is a much stronger inducer of ROS [46]. Furthermore, the abundance of copper in cancer cells enables DSF to specifically target cancer as opposed to normal tissues [47].

Copper ions promote ROS formation, which has been shown in multiple cancer cell lines [44]. Two forms of intracellular copper (cupric and cuprous) induce the formation of hydroxyl radicals from hydrogen peroxide, which serve to damage a variety of intracellular molecules [48]. Since studies have demonstrated that cytotoxicity of DSF appears to be copper dependent, the high concentration of copper in CSCs allows for an excellent substrate on which DSF can act in the treatment of cancer [43].

RA has been shown to inhibit proliferation of malignant tumors and induce apoptosis and differentiation [32, 4953]. Most notably, all-trans-retinoic acid (ATRA) is an effective treatment for acute promyelocytic leukemia (APL) and has been shown to result in complete remission [50, 54]. RA is derived from ATRA by the action of ALDHs. Since ALDH is often specifically upregulated in CSCs, clever design can exploit this pathway for tumor suppression [49].

In mouse model studies, the highly metastatic K7M2 OS cells seem to be preferentially targeted by RA [49]. The role of retinal in decreasing cell proliferation and cell survival was demonstrated by exposing cells to oxidative stress in the form of hydrogen peroxide. ALDH-high K7M2 cells exhibited a greater increase in apoptosis compared to ALDH-low cells. Additionally, RT-PCR demonstrated that retinal treatment resulted in downregulation of various genes involved in cell proliferation and cell survival in a dose-dependent manner [49]. This would suggest that retinal can effectively be used as a cellular “Trojan Horse” of sorts to specifically target OS cells, as the very ALDH-rich nature that is crucial to their metastatic potential leads to their willful acceptance and rapid metabolism of retinal, leading ultimately to their demise.

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3. Epidermal growth factor receptor (EGFR)

In order to obtain enough EGFR protein to biochemically purify and sequence, scientists initially used an epidermoid carcinoma cell line which was found to contain 100-fold higher levels of the receptor tyrosine kinase (TK). Since then, aberrant EGFR signaling has been implicated in the development and progression of many types of carcinomas including small cell lung, breast, stomach, prostate, ovarian, and glioblastoma. In the past decade, more attention has been placed on the role of EGFR signaling in OS.

3.1. Pathway physiology

Epidermal growth factor (EGF) was the first growth factor to be discovered and was found to have significant mitogenic effects of multiple cell types. Its receptor EGFR is a receptor tyrosine kinase (TK) which contains an extracellular domain where binding occurs to ligands of the EGF family such as, TGF-α, EGF, β-cellulin, epiregulin, and heparin-binding EGF. EGFR also contains a hydrophobic transmembrane region and a cytoplasmic TK domain [55]. Ligands bind to the cell surface domain and cause a conformational shift in the intracellular domain of the protein, which leads to dimerization and autophosphorylation. This phosphorylation then activates several other proteins downstream such as JNK, Akt, and mitogen-activated protein kinases (MAPK), which are responsible for normal cellular functions such as proliferation, apoptosis, adhesion, DNA synthesis, and migration. Signaling also occurs through other related TKs: HER2, HER3, and HER4. EGFR also has been shown to activate NFκB signaling, as well as being linked to certain G protein-coupled receptor signaling.

3.2. Pathophysiology

EGFR structure and function is closely related to erbB oncogene of avian erythroblastosis virus. The oncogene erbB is a part of a larger family of ErbB TKs including ErbB2 or HER2, HER3, and HER4. In addition, sequence anomalies found in the extracellular domain of EGFR were found to cause constitutive signal transduction independent of binding. Overexpressed EGFR levels in cancer cells also cause EGFR to undergo ligand-independent firing due to spontaneous activation of TK activity [56].

Recently, more attention to the action and therapeutic intervention of aberrant EGFR signaling in OS has been studied. Immunohistochemistry demonstrated high EGFR protein expression in 57% of 37 established bone tumor-derived cell lines [57]. Additionally, 90% of 27 OS biopsy samples showed moderate-to-high EGFR protein levels, as well as in four established OS cell lines HOS, KHOS/NP, MG-63, and U-2 OS . EGFR expression was not found to correlate to response to preoperative chemotherapy or survival [58]. Another group demonstrated that OS cell lines, MG-63 and Saos-2 proliferative abilities, were decreased by natural flavonoid Icariside II. Treatment also inactivated EGFR/mTOR signaling pathway including PI3K, serine/threonine protein kinase (Akt), mitogen-activated protein kinase kinase (MEK), and Extracellular-Signal-Regulated Kinases (ERK) [59].

3.3. Therapeutic applications

3.3.1. Gefitinib (Gef)

This molecular inhibitor of EGFR acts by binding to the cytoplasmic adenosine triphosphate binding site of the TK domain [60]. Signaling dysfunction leads to an inhibition of downstream malignant phenotypes through Akt, MAPK, and Ras signal cascades. Gef is used clinically in non–small-cell lung cancer known to be harboring aberrant EGFR levels, typically used in combination with other chemotherapy regimens.

Researchers have shown under serum starvation, EGFR inhibition in OS cells by Gef was more pronounced compared to normal conditions, suggesting that aberrant EGFR signaling contributes to OS progression but is not the major driver for proliferation. The EGFR inhibitor Gef was found to moderately synergize with doxorubicin and methotrexate in attenuating the proliferative capabilities of OS cell lines U-2 OS, Saos-2, OS-9, and others. Gef EGFR inhibition antagonized the cytotoxic effects of cisplatin [61].

3.3.2. Erlotinib (Erl)

Erl is another molecular inhibitor of EGFR via the ATP binding site of the cytoplasmic domain [62]. Erl is used in treating advanced metastatic non–small-cell lung cancer and pancreatic cancer, usually in combination with other chemotherapies.

Canine OS cell lines treated with another selective EGFR inhibitor Erl did not inhibit downstream protein kinase B (PKB/Akt) activation, and vascular endothelial growth factor (VEGF) levels increased. Conversely, Erl enhanced the effects of radiation therapy on a subset of OS cell lines [63].

3.3.3. Trastuzumab (Tra)

As the name suggests, Tra is a monoclonal antibody which interferes with normal HER2 receptor functioning of EGFR [64]. It has been suggested that Tra does not alter receptor expression but instead causes inhibition of downstream Akt and MAPK proliferation signaling. A phase II clinical trial of metastatic OS with EGFR2 overexpression showed that Tra can be safely delivered in combination with anthracycline-based chemotherapy [65].

Targeting one substrate of the receptor TK signaling cascade is likely insufficient to effectively abrogate downstream effects. Incremental improvements for the treatments of OS will depend on the novel chemotherapeutic interactions now being observed in the laboratory. BreAkthroughs will occur by further testing intricate combination therapies including sensitizers like EGFR inhibitors (Erl and Gef) with traditional chemotherapeutics such as doxorubicin, methotrexate, and cisplatin.

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4. Insulin-like growth factor-1 receptor (IGFR-1R)

Insulin-like growth factor-1 receptor (IGF-1R) has been shown to play role in various cancers, including pediatric sarcomas. IGF-1R is just one cog in the complicated system of insulin-like growth factor (IGF) and insulin family of growth factors and is located in various tissues including bone. It plays an important role in regulating bone homeostasis, and activation of this unique TK receptor leads to several important downstream signaling cascades that play a crucial role in cell proliferation and protein synthesis. Aberrant signaling in the IGF-1R pathway may be implicated in the development of OS. Studying the basic physiology and pathophysiology in this pathway has been critical to the development of OS-targeted therapy. Here, we examine the basic biology of IGF-1R in relation to OS- and molecular-targeted therapies that exploit this signaling pathway.

4.1. Physiology

IGF-1R signaling is involved in normal osteogenesis and bone homeostasis [66]. IGF-1R is a type II receptor TK consisting of two α- and two β-subunits. The binding of IGF-1 to IGF-1R induces autophosphorylation of tyrosine residues in the kinase domain. This autophosphorylation leads to the downstream activation of insulin receptor substrate (IRS) proteins and Shc, an adapter protein between IGF-IR and the network of their signaling pathways [67, 68] (Figure 2). Phosphorylation of Shc and its binding to Grb2 is required for the activation of mitogen-activated protein kinases (MAPK)/extracellular-signal-regulated kinases (ERK), both important regulators of proliferation, invasion, angiogenesis, and inflammatory responses [69, 70].

Figure 2.

IGF-1 signaling pathway which can activate MAPK and PI3K signaling pathways.

There are four isomers of IRS, and of these isomers, IRS1 and IRS2 are expressed in osteoblasts. These adaptors are important in normal bone turnover. Furthermore, deficiencies in IRS1/2 impair osteoblast proliferation and differentiation and result in decreased bone mass [71, 72]. IRS1 is one of the many activators of phosphatidylinositol 3 kinase (PI3K). PI3K converts phosphatidylinositol 4,5-biphosphate (PIP2) into phosphatidylinositol 3,4,5-triphosphate (PIP3), which then recruits the signaling proteins PDK1 and Akt to the plasma membrane [73]. The PI3K/Akt pathway is implicated in the proliferation and invasion of malignant OS via multiple pathways, such as increasing the expression of cyclins and cyclin-dependent kinases that act as positive regulators of the cell cycle in OS [74]. The mammalian target of rapamycin (mTOR) is one of the most important downstream effectors of PI3K/Akt and controls cell cycling and protein synthesis by activation of its downstream targets p70S6K and 4E-BP [68].

Aside from regulating insulin’s control of carbohydrate metabolism, the ligands IGF-1 and IGF2 may play a role in the neoplasticity of OS [75]. It has been demonstrated that there may be increased local IGF-1 levels in primary OS, which may affect survival, aggressiveness, and chemotherapeutic response [76]. Activation of IGF-1R by IGF-I stimulates OS cell growth in vitro and in vivo [77]. IGF-1 levels peak during adolescence, also the same age where OS incidences peak [78]. Interestingly, IGF-2 levels are increased in OS after chemotherapy treatment and may increase OS cell survival by inducing an autophagic state of dormancy, protecting OS against chemotherapy [79]. These ligands’ influences in the tumorigenicity of OS have made them attractive targets in OS treatment. However, the only IGF-1 neutralizing antibody in clinical trials is MEDI-573 and is still in the early stages of development [80].

It is not completely clear yet whether mutations in IGF-1R contribute to cell growth, differentiation, apoptosis, and so on. Interestingly, mutations in IGF-1R are rare and produce growth retardation rather than neoplasia [81]. The recent discovery of somatic mutations in the IGF-1R kinase catalytic domain showed a small reduction in peptide phosphorylation. However, the mutant kinase domains were active, not hyper-activated relative to the wildtype [82]. Interactions between wildtype and mutant variants of the tumor suppressor gene, p53, and IGF-1R have also been studied. Normally, p53 suppresses the activity of IGF-1R, thus preventing cell proliferation. However, mutant variants of p53 derived from tumor have shown to enhance promotor activity and increase the transcription of IGF-1R, increasing the survivability of malignant cells [81, 83, 84].

4.2. Therapeutic applications

Currently, there are several IGF-1R inhibitors categorized into TK inhibitors, monoclonal antibodies, or microRNA targets of IGF-1R. Monoclonal antibodies against IGF-1R ligands have been studied but may be ineffective because of the redundancy in autocrine and paracrine secretion of this growth factor [85]. Several monoclonal antibodies against IGF-1R, such as Ganitumab or Dalotuzumab, are still being tested but tend to have a stronger inhibitory effect when combined with other therapies such as Rapamycin, an mTOR inhibitor [80 ]. Here, we focus on one small molecular IGF-1R inhibitor, OSI-906, and assess its current status in OS therapy.

The ATP-binding or substrate-binding site in the IGF-1R kinase domain can be targeted by small-molecule inhibitors, thus inhibiting IGF-1R signaling. An example of these inhibitors is OSI-906 (Linsitinib), a highly selective, small-molecule dual IGF-1R/IR kinase inhibitor given in an oral formulation that is in clinical trial. It has been shown that OSI-906 inhibits the downstream effectors of IGF-1R, ERK1/2 and Akt, thus affecting cell survival and proliferation [86]. One of the issues with molecular targeting of IGF-1R is the high degree of homology between the binding sites in IGF-1R and the insulin receptor. Molecular targets that cross-react with the insulin receptor may produce unwanted side effects such as dysregulating glucose metabolism [87]. Fortunately, OSI-906 exhibits a nine-fold selectivity for human IGF-1R over human insulin receptor [88]. The inhibitory effect of OSI-906 was tested on four unique OS cell lines and was found to inhibit phosphorylation of IRS-1 and proliferation in three of the four OS cell lines tested [89]. OSI-906 in combination with the EGFR inhibitor, Erl, has also been tested on human colorectal cancer cell lines and found to exhibit a synergistic inhibition of cell proliferation and survival [88]. Though OSI-906 has been somewhat successful as a single-agent for inhibiting IGF-1R in OS, further studies examining combination therapies with OSI-906 are necessary.

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5. Conclusion

There is definitely hope and evidence to apply targeted molecular therapies to treat OS. As our understanding of the different molecular pathways that affect OS improves, we will be better equipped to attack this disease in ways that were not available before. Though numerous molecular pathways have been described here, it is important to understand that there are many more pathways that exist or are under investigation. Clearly, there is still much to learn about the biology of OS and its targeted therapies. The weight of evidence described above suggests that we are steadily moving forward in the right direction.

References

  1. 1. Guise TA, O'Keefe R, Randall RL, Terek RM: Molecular biology and therapeutics in musculoskeletal oncology. J Bone Joint Surg Am 2009, 91(3):724–732.
  2. 2. Duchman KR, Gao Y, Miller BJ: Prognostic factors for survival in patients with high-grade osteosarcoma using the Surveillance, Epidemiology, and End Results (SEER) Program database. Cancer Epidemiol 2015, 39(4):593–599.
  3. 3. Oeffinger KC, Mertens AC, Sklar CA, Kawashima T, Hudson MM, Meadows AT, Friedman DL, Marina N, Hobbie W, Kadan-Lottick NS et al: Chronic health conditions in adult survivors of childhood cancer. N Engl J Med 2006, 355(15):1572–1582.
  4. 4. Xu X, Chai S, Wang P, Zhang C, Yang Y, Yang Y, Wang K: Aldehyde dehydrogenases and cancer stem cells. Cancer Lett 2015, 369(1):50–57.
  5. 5. Marchitti SA, Brocker C, Stagos D, Vasiliou V: Non-P450 aldehyde oxidizing enzymes: the aldehyde dehydrogenase superfamily. Expert Opin Drug Metab Toxicol 2008, 4(6):697–720.
  6. 6. Shi X, Zhang Y, Zheng J, Pan J: Reactive oxygen species in cancer stem cells. Antioxid Redox Signal 2012, 16(11):1215–1228.
  7. 7. Greco N, Schott T, Mu X, Rothenberg A, Voigt C, McGough Iii RL, Goodman M, Huard J, Weiss KR: ALDH activity correlates with metastatic potential in primary sarcomas of bone. J Cancer Ther 2014, 5(4):331–338.
  8. 8. Theruvathu JA, Nath RG, Brooks PJ: Polyamines facilitate the formation of the mutagenic DNA adduct 1, N-2-PropanodG from acetaldehyde and DNA: implications for the mechanism of alcohol-related carcinogenesis. In: 2004: Wiley-Liss Div John Wiley & Sons Inc, Hoboken, NJ: 231.
  9. 9. Brooks PJ, Theruvathu JA: DNA adducts from acetaldehyde: implications for alcohol-related carcinogenesis. Alcohol 2005, 35:187–193.
  10. 10. Croker AK, Goodale D, Chu J, Postenka C, Hedley BD: High aldehyde dehydrogenase and expression of cancer stem cell markers selects for breast cancer cells with enhanced malignant and metastatic ability. J Cell Mol Med 2009, 13(8B):2236–2252.
  11. 11. Su Y, Qiu Q, Zhang X, Jiang Z, Leng Q, Liu Z, Stass SA, Jiang F: Aldehyde Dehydrogenase 1 A1–Positive Cell Population Is Enriched in Tumor-Initiating Cells and Associated with Progression of Bladder Cancer. Cancer Epidemiol Biomarkers Prev 2010, 19(2):327–338.
  12. 12. Douville J, Beaulieu R, Balicki D: ALDH1 as a functional marker of cancer stem and progenitor cells. Stem Cells Dev 2009, 18(1):17–25.
  13. 13. Bortolomai I, Canevari S, Facetti I, Cecco LD, Zacchetti A, Alison MR, Miotti S, Bortolomai I, Canevari S, Facetti I et al: Tumor initiating cells: development and critical characterization of a model derived from the A431 carcinoma cell line forming spheres in suspension. Cell Cycle 2010, 9(6):1194–1206.
  14. 14. Ginestier C, Hur MH, Charafe-jauffret E, Monville F, Dutcher J, Brown M, Jacquemier J, Viens P, Kleer CG, Liu S et al: ALDH1 is a marker of normal and malignant human mammary stem cells and a predictor of poor clinical outcome. Cell Stem Cell 2007, 1:555–567.
  15. 15. Mu X, Isaac C, Greco N, Huard J, Weiss K: Notch signaling is associated with ALDH activity and an aggressive metastatic phenotype in murine osteosarcoma cells. Front Oncol 2013, 3(June):1–10.
  16. 16. Mu X, Isaac C, Schott T, Huard J, Weiss K: Rapamycin inhibits ALDH activity, resistance to oxidative stress, and metastatic potential in murine osteosarcoma cells. Sarcoma 2013, 2013:1–11.
  17. 17. Gorrini C, Harris IS, Mak TW: Modulation of oxidative stress as an anticancer strategy. Nat Rev 2013, 12(12):931–947.
  18. 18. Singh S, Brocker C, Koppaka V, Ying C, Jackson B, Thompson DC, Vasiliou V: Aldehyde dehydrogenases in cellular responses to oxidative/electrophilic stress. Free Radic Biol Med 2013, 56:89–101.
  19. 19. Ikeda J-i, Mamat S, Tian T, Wang Y, Luo W, Rahadiani N, Aozasa K, Morii E: Reactive oxygen species and aldehyde dehydrogenase activity in Hodgkin lymphoma cells. Lab Invest 2012, 92(4):606–614.
  20. 20. Mizuno T, Suzuki N, Makino H, Furui T, Morii E, Aoki H, Kunisada T, Yano M, Kuji S, Hirashima Y et al: Cancer stem-like cells of ovarian clear cell carcinoma are enriched in the ALDH-high population associated with an accelerated scavenging system in reactive oxygen species. Gynecol Oncol 2015, 137(2):299305.
  21. 21. Ye X-q, Li Q, Wang G-h, Sun F-f, Huang G-j, Bian X-w, Yu S-c, Qian G-S: Mitochondrial and energy metabolism-related properties as novel indicators of lung cancer stem cells. Int J Cancer 2011, 129:820–831.
  22. 22. Diehn M, Cho RW, Lobo NA, Kalisky T, Dorie MJ, Kulp AN, Qian D, Lam JS, Ailles LE, Wong M et al: Association of reactive oxygen species levels and radioresistance in cancer stem cells. Nature 2009, 458:6–11.
  23. 23. Allensworth JL, Evans MK, Aldrich J, Festa RA, Finetti P, Ueno NT, Safi R, McDonnell DP, Thiele DJ, Laere SV et al: Disulfiram (DSF) acts as a copper ionophore to induce copper-dependent oxidative stress and mediate anti-tumor efficacy in inflammatory breast cancer. Mol Oncol 2015, 9:1155–1168.
  24. 24. Chiba T, Suzuki E, Yuki K, Zen Y, Oshima M, Miyagi S, Tawada A, Nakatsura T, Hayashi T, Yamashita T et al: Disulfiram eradicates tumor-initiating hepatocellular carcinoma cells in ROS-p38 MAPK pathway-dependent and -independent manners. PLoS ONE 2014, 9(1):1–11.
  25. 25. Croker AK, Allan AL: Inhibition of aldehyde dehydrogenase (ALDH) activity reduces chemotherapy and radiation resistance of stem-like ALDH hi CD44 + human breast cancer cells. Breast Cancer Res Treat 2012, 133:75–87.
  26. 26. Brennan SK, Meade B, Wang Q, Merchant AA, Kowalski J, Matsui W: Mantle cell lymphoma activation enhances bortezomib sensitivity. Blood 2010, 116(20):4185–4191.
  27. 27. Magni M, Shammah S, Schiro R, Mellado W, Dalla-Favera R, Gianni AM: Induction of cyclophosphamide-resistance by aldehyde-dehydrogenase gene transfer. Blood 1996, 8(3):1097–1103.
  28. 28. Dylla SJ, Beviglia L, Park I-k, Chartier C, Raval J, Ngan L, Aguilar J, Lazetic S, Smith-berdan S, Clarke MF et al: Colorectal cancer stem cells are enriched in xenogeneic tumors following chemotherapy. PLoS ONE 2008, 3(6):e2428–e2428.
  29. 29. Chanda B, Ditadi A, Iscove NN, Keller G: Retinoic acid signaling is essential for embryonic hematopoietic stem cell development. Cell 2013, 155(1):215–227.
  30. 30. Qiu JJ, Zeisig BB, Li S, Liu W, Chu H, Song Y, Giordano A, Schwaller J, Gronemeyer H, Dong S et al: Critical role of retinoid/rexinoid signaling in mediating transformation and therapeutic response of NUP98-RARG leukemia. Leukemia 2015, 29:1153–1162.
  31. 31. Dragnev KH, Petty WJ, Dmitrovsky E: Retinoid targets in cancer therapy and chemoprevention. Cancer Biol Ther 2003, 2(4):S150–S156.
  32. 32. Ginestier C, Wicinski J, Cervera N, Monville F, Finetti P, Bertucci F, Wicha MS, Birnbaum D, Ginestier C, Wicinski J et al: Retinoid signaling regulates breast cancer stem cell differentiation. Cell Cycle 2009, 8(20):3297–3302.
  33. 33. Ying M, Wang S, Sang Y, Sun P, Lal B, Goodwin CR, Laterra J, Xia S: Regulation of glioblastoma stem cells by retinoic acid: role for Notch pathway inhibition. Oncogene 2011, 30:3454–3467.
  34. 34. Rae C, Tesson M, Babich JW, Boyd M, Sorensen A, Mairs RJ: The role of copper in disulfiram-induced toxicity and radiosensitization of cancer cells. J Nucl Med 2013, 54(6):953–960.
  35. 35. Zhang H, Chen D, Ringler J, Chen W, Cui QC, Ethier SP, Dou QP, Wu G: Disulfiram treatment facilitates phosphoinositide 3-kinase inhibition in human breast cancer cells in vitro and in vivo. Cancer Res 2010, 70(10):3996–4004.
  36. 36. Paranjpe A, Srivenugopal KS: Degradation of NF-κB, p53 and other regulatory redox-sensitive proteins by thiol-conjugating and-nitrosylating drugs in human tumor cells. Carcinogenesis 2013:bgt032–bgt032.
  37. 37. Yip NC, Fombon IS, Liu P, Brown S, Kannappan V, Armesilla AL, Xu B, Cassidy J, Darling JL, Wang W: Disulfiram modulated ROS–MAPK and NFκB pathways and targeted breast cancer cells with cancer stem cell-like properties. Br J Cancer 2011, 104(10):1564–1574.
  38. 38. Xu B, Shi P, Fombon IS, Zhang Y, Huang F, Wang W, Zhou S: Disulfiram/copper complex activated JNK/c-jun pathway and sensitized cytotoxicity of doxorubicin in doxorubicin resistant leukemia HL60 cells. Blood Cells Mol Dis 2011, 47(4):264–269.
  39. 39. Tirino V, Desiderio V, Paino F, De Rosa A, Papaccio F, La Noce M, Laino L, De Francesco F, Papaccio G: Cancer stem cells in solid tumors: an overview and new approaches for their isolation and characterization. FASEB J 2013, 27(1):13–24.
  40. 40. Triscott J, Lee C, Hu K, Fotovati A, Berns R, Pambid M, Luk M, Kast RE, Kong E, Toyota E: Disulfiram, a drug widely used to control alcoholism, suppresses the self-renewal of glioblastoma and over-rides resistance to temozolomide. Oncotarget 2012, 3(10):1112–1123.
  41. 41. Liu P, Kumar IS, Brown S, Kannappan V, Tawari PE, Tang JZ, Jiang W, Armesilla AL, Darling JL, Wang W: Disulfiram targets cancer stem-like cells and reverses resistance and cross-resistance in acquired paclitaxel-resistant triple-negative breast cancer cells. Br J Cancer 2013, 109:1876–1885.
  42. 42. Cho H-j, Lee T-s, Park J-b, Park K-k, Choe J-y, Sin D-i, Park Y-y, Moon Y-s, Lee K-g, Yeo J-h et al: Disulfiram suppresses invasive ability of osteosarcoma cells via the inhibition of MMP-2 and MMP-9 expression. J Biochem Mol Biol 2007, 40(6):1069–1076.
  43. 43. Liu P, Brown S, Goktug T, Channathodiyil P, Kannappan V, Hugnot JP, Guichet PO, Bian X, Armesilla AL, Darling JL: Cytotoxic effect of disulfiram/copper on human glioblastoma cell lines and ALDH-positive cancer-stem-like cells. Br J Cancer 2012, 107(9):1488–1497.
  44. 44. Tardito S, Bassanetti I, Bignardi C, Elviri L, Tegoni M, Mucchino C, Bussolati O, Franchi-Gazzola R, Marchiò L: Copper binding agents acting as copper ionophores lead to caspase inhibition and paraptotic cell death in human cancer cells. J Am Chem Soc 2011, 133(16):6235–6242.
  45. 45. Duan L, Shen H, Zhao G, Yang R, Cai X, Zhang L, Jin C, Huang Y: Inhibitory effect of disulfiram/copper complex on non-small cell lung cancer cells. Biochem Biophys Res Commun 2014, 446(4):1010–1016.
  46. 46. Nagai M, Vo NH, Ogawa LS, Chimmanamada D, Inoue T, Chu J, Beaudette-Zlatanova BC, Lu R, Blackman RK, Barsoum J: The oncology drug elesclomol selectively transports copper to the mitochondria to induce oxidative stress in cancer cells. Free Radic Biol Med 2012, 52(10):2142–2150.
  47. 47. Wang F, Jiao P, Qi M, Frezza M, Dou QP, Yan B: Turning tumor-promoting copper into an anti-cancer weapon via high-throughput chemistry. Curr Med Chem 2010, 17(25):2685–2698.
  48. 48. Eguchi H, Ikeda Y, Koyota S, Honke K, Suzuki K, Gutteridge JMC, Taniguchi N: Oxidative damage due to copper ion and hydrogen peroxide induces GlcNAc-specific cleavage of an Asn-linked oligosaccharide. J Biochem 2002, 131(3):477–484.
  49. 49. Mu X, Patel S, Mektepbayeva D, Mahjoub A, Huard J, Weiss K: Retinal targets ALDH positive cancer stem cell and alters the phenotype of highly metastatic osteosarcoma cells. Sarcoma 2015, 2015:14–16.
  50. 50. Tang X-h, Gudas LJ: Retinoids, retinoic acid receptors, and cancer. Annu Rev Pathol Mech Dis 2011, 6:345–364.
  51. 51. Schenk T, Stengel S, Zelent A: Unlocking the potential of retinoic acid in anticancer therapy. Br J Cancer 2014, 111:2039–2045.
  52. 52. Chen M-c, Huang C-y, Hsu S-l, Lin E, Ku C-t, Lin H, Chen C-m: Retinoic acid induces apoptosis of prostate cancer DU145 cells through Cdk5 overactivation. Evid Based Complement Alternat Med 2012:1–11.
  53. 53. Huss WJ, Lai L, Barrios RJ, Hirschi KK, Greenberg NM: Retinoic acid slows progression and promotes apoptosis of spontaneous prostate cancer. The Prostate 2004, 9999:1–11.
  54. 54. Huang M-e, Ye Y-c, Chen S-r, Chai J-r, Lu J-X, Zhao L, Gu L-j, Wang Z-y: Use of all-trans retinoic acid in the treatment of acute promyelocytic leukemia. Blood 1988, 72(2):567–572.
  55. 55. Yufen X, Binbin S, Wenyu C, Jialiang L, Xinmei Y: The role of EGFR-TKI for leptomeningeal metastases from non-small cell lung cancer. Springerplus 2016, 5(1):1244.
  56. 56. Normanno N, De Luca A, Bianco C, Strizzi L, Mancino M, Maiello MR, Carotenuto A, De Feo G, Caponigro F, Salomon DS: Epidermal growth factor receptor (EGFR) signaling in cancer. Gene 2006, 366(1):2–16.
  57. 57. Wen YH, Koeppen H, Garcia R, Chiriboga L, Tarlow BD, Peters BA, Eigenbrot C, Yee H, Steiner G, Greco MA: Epidermal growth factor receptor in osteosarcoma: expression and mutational analysis. Hum Pathol 2007, 38(8):1184–1191.
  58. 58. Lee JA, Ko Y, Kim DH, Lim JS, Kong CB, Cho WH, Jeon DG, Lee SY, Koh JS: Epidermal growth factor receptor: is it a feasible target for the treatment of osteosarcoma? Cancer Res Treat 2012, 44(3):202–209.
  59. 59. Geng YD, Yang L, Zhang C, Kong LY: Blockade of epidermal growth factor receptor/mammalian target of rapamycin pathway by Icariside II results in reduced cell proliferation of osteosarcoma cells. Food Chem Toxicol 2014, 73:7–16.
  60. 60. Lynch TJ, Bell DW, Sordella R, Gurubhagavatula S, Okimoto RA, Brannigan BW, Harris PL, Haserlat SM, Supko JG, Haluska FG et al: Activating mutations in the epidermal growth factor receptor underlying responsiveness of non-small-cell lung cancer to gefitinib. N Engl J Med 2004, 350(21):2129–2139.
  61. 61. Mok TS, Wu YL, Thongprasert S, Yang CH, Chu DT, Saijo N, Sunpaweravong P, Han B, Margono B, Ichinose Y et al: Gefitinib or carboplatin-paclitaxel in pulmonary adenocarcinoma. N Engl J Med 2009, 361(10):947–957.
  62. 62. Raymond E, Faivre S, Armand JP: Epidermal growth factor receptor tyrosine kinase as a target for anticancer therapy. Drugs 2000, 60 Suppl 1:15–23; discussion 41–12.
  63. 63. Mantovani FB, Morrison JA, Mutsaers AJ: Effects of epidermal growth factor receptor kinase inhibition on radiation response in canine osteosarcoma cells. BMC Vet Res 2016, 12:82.
  64. 64. Hudis CA: Trastuzumab—mechanism of action and use in clinical practice. N Engl J Med 2007, 357(1):39–51.
  65. 65. Ebb D, Meyers P, Grier H, Bernstein M, Gorlick R, Lipshultz SE, Krailo M, Devidas M, Barkauskas DA, Siegal GP et al: Phase II trial of trastuzumab in combination with cytotoxic chemotherapy for treatment of metastatic osteosarcoma with human epidermal growth factor receptor 2 overexpression: a report from the children's oncology group. J Clin Oncol 2012, 30(20):2545–2551.
  66. 66. McCarthy TL, Centrella M: Local IGF-I expression and bone formation. Growth Horm IGF Res 2001, 11(4):213–219.
  67. 67. Hernandez-Sanchez C, Blakesley V, Kalebic T, Helman L, LeRoith D: The role of the tyrosine kinase domain of the insulin-like growth factor-I receptor in intracellular signaling, cellular proliferation, and tumorigenesis. J Biol Chem 1995, 270(49):29176–29181.
  68. 68. Guntur AR, Rosen CJ: IGF-1 regulation of key signaling pathways in bone. Bonekey Rep 2013, 2:437.
  69. 69. Chandhanayingyong C, Kim Y, Staples JR, Hahn C, Lee FY: MAPK/ERK signaling in osteosarcomas, ewing sarcomas and chondrosarcomas: therapeutic implications and future directions. Sarcoma 2012, 2012:404810.
  70. 70. Ling Y, Maile LA, Lieskovska J, Badley-Clarke J, Clemmons DR: Role of SHPS-1 in the regulation of insulin-like growth factor I-stimulated Shc and mitogen-activated protein kinase activation in vascular smooth muscle cells. Mol Biol Cell 2005, 16(7):3353–3364.
  71. 71. Akune T, Ogata N, Hoshi K, Kubota N, Terauchi Y, Tobe K, Takagi H, Azuma Y, Kadowaki T, Nakamura K et al: Insulin receptor substrate-2 maintains predominance of anabolic function over catabolic function of osteoblasts. J Cell Biol 2002, 159(1):147–156.
  72. 72. Ogata N, Chikazu D, Kubota N, Terauchi Y, Tobe K, Azuma Y, Ohta T, Kadowaki T, Nakamura K, Kawaguchi H: Insulin receptor substrate-1 in osteoblast is indispensable for maintaining bone turnover. J Clin Invest 2000, 105(7):935–943.
  73. 73. Rubashkin MG, Cassereau L, Bainer R, DuFort CC, Yui Y, Ou G, Paszek MJ, Davidson MW, Chen YY, Weaver VM: Force engages vinculin and promotes tumor progression by enhancing PI3K activation of phosphatidylinositol (3,4,5)-triphosphate. Cancer Res 2014, 74(17):4597–4611.
  74. 74. Zhang J, Yu XH, Yan YG, Wang C, Wang WJ: PI3K/Akt signaling in osteosarcoma. Clin Chim Acta 2015, 444:182–192.
  75. 75. Burrow S, Andrulis IL, Pollak M, Bell RS: Expression of insulin-like growth factor receptor, IGF-1, and IGF-2 in primary and metastatic osteosarcoma. J Surg Oncol 1998, 69(1):21–27.
  76. 76. Jentzsch T, Robl B, Husmann M, Bode-Lesniewska B, Fuchs B: Worse prognosis of osteosarcoma patients expressing IGF-1 on a tissue microarray. Anticancer Res 2014, 34(8):3881–3889.
  77. 77. Rikhof B, de Jong S, Suurmeijer AJ, Meijer C, van der Graaf WT: The insulin-like growth factor system and sarcomas. J Pathol 2009, 217(4):469–482.
  78. 78. Duan Z, Choy E, Harmon D, Yang C, Ryu K, Schwab J, Mankin H, Hornicek FJ: Insulin-like growth factor-I receptor tyrosine kinase inhibitor cyclolignan picropodophyllin inhibits proliferation and induces apoptosis in multidrug resistant osteosarcoma cell lines. Mol Cancer Ther 2009, 8(8):2122–2130.
  79. 79. Shimizu T, Sugihara E, Yamaguchi-Iwai S, Tamaki S, Koyama Y, Kamel W, Ueki A, Ishikawa T, Chiyoda T, Osuka S et al: IGF2 preserves osteosarcoma cell survival by creating an autophagic state of dormancy that protects cells against chemotherapeutic stress. Cancer Res 2014, 74(22):6531–6541.
  80. 80. Chen HX, Sharon E: IGF-1R as an anti-cancer target—trials and tribulations. Chin J Cancer 2013, 32(5):242–252.
  81. 81. Werner H: Tumor suppressors govern insulin-like growth factor signaling pathways: implications in metabolism and cancer. Oncogene 2012, 31(22):2703–2714.
  82. 82. Craddock BP, Miller WT: Effects of somatic mutations in the C-terminus of insulin-like growth factor 1 receptor on activity and signaling. J Signal Transduct 2012, 2012:804801.
  83. 83. Werner H, Karnieli E, Rauscher FJ, LeRoith D: Wild-type and mutant p53 differentially regulate transcription of the insulin-like growth factor I receptor gene. Proc Natl Acad Sci U S A 1996, 93(16):8318–8323.
  84. 84. Idelman G, Glaser T, Roberts CT, Jr., Werner H: WT1-p53 interactions in insulin-like growth factor-I receptor gene regulation. J Biol Chem 2003, 278(5):3474–3482.
  85. 85. Benini S, Baldini N, Manara MC, Chano T, Serra M, Rizzi S, Lollini PL, Picci P, Scotlandi K: Redundancy of autocrine loops in human osteosarcoma cells. Int J Cancer 1999, 80(4):581–588.
  86. 86. Mulvihill MJ, Cooke A, Rosenfeld-Franklin M, Buck E, Foreman K, Landfair D, O'Connor M, Pirritt C, Sun Y, Yao Y et al: Discovery of OSI-906: a selective and orally efficacious dual inhibitor of the IGF-1 receptor and insulin receptor. Future Med Chem 2009, 1(6):1153–1171.
  87. 87. Sachdev D, Yee D: Disrupting insulin-like growth factor signaling as a potential cancer therapy. Mol Cancer Ther 2007, 6(1):1–12.
  88. 88. Ji QS, Mulvihil MJ, Rosenfeld-Franklin M, Buck E, Cooke A, Eyzaguirrel A, Mak G, O'Connor M, Pirritt C, Yao Y et al: Preclinical characterization of OSI-906: A novel IGF-1R kinase inhibitor in clinical trials. Molecular Cancer Therapeutics 2007, 6(12):3590s–3590s.
  89. 89. Kuijjer ML, Peterse EF, van den Akker BE, Briaire-de Bruijn IH, Serra M, Meza-Zepeda LA, Myklebost O, Hassan AB, Hogendoorn PC, Cleton-Jansen AM: IR/IGF1R signaling as potential target for treatment of high-grade osteosarcoma. BMC Cancer 2013, 13:245.

Written By

Adel Mahjoub, Jared A. Crasto, Jonathan Mandell, Mitchell S. Fourman, Rashmi Agarwal and Kurt R. Weiss

Reviewed: 26 January 2017 Published: 26 April 2017