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Supplementary Figures and Legends.

Young BODIPY-C12 fibroblasts with GFP-Tagged melanoma cells showing lipid uptake

Aged BODIPY-C12 fibroblasts with GFP-tagged melanoma cells

Older patients with melanoma (>50 years old) have poorer prognoses and response rates to targeted therapy compared with young patients (Significance:These data show that melanoma cells take up lipids from aged fibroblasts, via FATP2, and use them to resist targeted therapy. The response to targeted therapy is altered in aged individuals because of the influences of the aged microenvironment, and these data suggest FATP2 as a target to overcome resistance.See related commentary by Montal and White, p. 1255..This article is highlighted in the In This Issue feature, p. 1241

Aged BODIPY-C12 fibroblasts with GFP-tagged melanoma cells

Young BODIPY-C12 fibroblasts with GFP-Tagged melanoma cells showing lipid uptake

Supplementary Tables

Supplementary Figure 4

Supplementary Figure 7 - Pro- and Anti-Tumor Effects of IFN-g Signalling Within The TME

Purpose: Aging is a poor prognostic factor for melanoma. We have shown that melanoma cells in an aged microenvironment are more resistant to targeted therapy than identical cells in a young microenvironment. This is dependent on age-related secreted factors. Klotho is an age-related protein whose serum levels decrease dramatically by age 40. Most studies on klotho in cancer have focused on the expression of klotho in the tumor cell. We have shown that exogenous klotho inhibits internalization and signaling of Wnt5A, which drives melanoma metastasis and resistance to targeted therapy. We investigate here whether increasing klotho in the aged microenvironment could be an effective strategy for the treatment of melanoma.Experimental Design: PPARγ increases klotho levels and is increased by glitazones. Using rosiglitazone, we queried the effects of rosiglitazone on Klotho/Wnt5A cross-talk, in vitro and in vivo, and the implications of that for targeted therapy in young versus aged animals.Results: We show that rosiglitazone increases klotho and decreases Wnt5A in tumor cells, reducing the burden of both BRAF inhibitor–sensitive and BRAF inhibitor–resistant tumors in aged, but not young mice. However, when used in combination with PLX4720, tumor burden was reduced in both young and aged mice, even in resistant tumors.Conclusions: Using glitazones as adjuvant therapy for melanoma may provide a new treatment strategy for older melanoma patients who have developed resistance to vemurafenib. As klotho has been shown to play a role in other cancers too, our results may have wide relevance for multiple tumor types. Clin Cancer Res; 23(12); 3181–90. ©2017 AACR.

Figure S1: Wnt5A expression correlates with high autophagy in melanoma. Figure S2: Wnt5A increases autophagy in melanoma Figure S3: ATG5 affects Wnt signaling in melanoma Figure S4: β-catenin increases the sensitivity of melanoma cells to autophagy inhibition Supplemental Figure Legends SUPPLEMENTAL TABLE 1: DENSITOMETRY FOR ALL WESTERNS Supplemental Table 2. Tissue microarrays (TMA) H scores

Autophagy mediates resistance to various anticancer agents. In melanoma, resistance to targeted therapy has been linked to expression of Wnt5A, an intrinsic inhibitor of β-catenin, which also promotes invasion. In this study, we assessed the interplay between Wnt5A and autophagy by combining expression studies in human clinical biopsies with functional analyses in cell lines and mouse models. Melanoma cells with high Wnt5A and low β-catenin displayed increased basal autophagy. Genetic blockade of autophagy revealed an unexpected feedback loop whereby knocking down the autophagy factor ATG5 in Wnt5Ahigh cells decreased Wnt5A and increased β-catenin. To define the physiologic relevance of this loop, melanoma cells with different Wnt status were treated in vitro and in vivo with the potent lysosomotropic compound Lys05. Wnt5Ahigh cells were less sensitive to Lys05 and could be reverted by inducing β-catenin activity. Our results suggest the efficacy of autophagy inhibitors might be improved by taking the Wnt signature of melanoma cells into account. Cancer Res; 77(21); 5873–85. ©2017 AACR.

Legends to supplementary figures

Supplementary Figure 5

Supplementary Figure 2

PDF containing all supplementary figures. Supplementary Figure Legends. Supplemental Figure 1. A, graph indicating the number of patients for which best response data to pembrolizumab was obtained, and from which institution. B, various response groups of patients treated with pembrolizumab, separated by gender, and using 62 years of age as the most statistically significant cut-off. Supplemental Figure 2. A, B Change in mouse weight on final day of experiment from start in female and male mice bearing BSC9AJ2 tumors, after treatment with 3 doses of 300µg rat IgG2AK (N=5) or 4 doses of 300µg anti-PD1 (N=5) every 5 days, starting on day 0. Supplemental Figure 3. A, CD45+ cells within Yumm1.7 and B. BSC9AJ2 tumors. Err=95%CI. B, CD45+ cells within in tumors of Yumm1.7 and Yumm2.1 tumors. C, CD8b+ cells following 5 hour incubation with PMA and ionomycin analyzed by FACS analysis. Err=SD. D, E CD45+CD8b+ cells expressing TNFα and IFNγ within spleens from mice harboring Yumm1.7 or BSC9AJ2 tumors. Err=95%CI. Significance was determined using individual two-tailed student's t-test assuming unequal variance for 1-2 factors and using a 2-way ANOVA for 3 or more factors. Supplemental Figure 4. A 10X view with 40X zoom of FOXP3+ foci staining in melanoma patient biopsies. B, FOXP3+ staining from patient tumors across various age groups. C, CD8+ staining from patient tumors across various age groups. D, percentages of patients in the indicated age groups, whose CD8:FOXP3 ratio is low (< median - 1), med (median +/- 1), or high (> median + 1). Supplemental Figure 5. A. Mouse weight on final day of experiment from start in mice treated with anti-CD25 or an IgG1A isotype 5 days prior to sub-dermal of BSC9AJ2 cells with treatments continuing every 5 days until sacrifice. Anti-PD1 was administered every 3-4 days, starting on day 9 post-tumoral injection. Err=95%CI. Statistical significance determined by 2 way ANOVA. Err bars = SEM. B. Tumor growth for individual mice, per condition in A. Supplemental Figure 6. A. Ratios of CD3+CD8a+ to CD3+CD4+FoxP3+ in BSC9AJ2 tumors from young female mice 4 days following cyclophosphamide intraperitoneal injection at indicated doses. 5 mice in PBS group, and 3 mice per dose. Err=SEM. B, intra-tumoral CD3+CD4+FoxP3+ populations. Err=SD. C, tumor growth in young female mice bearing BSC9AJ2 tumors were injected 6 days post tumor implantation with either 100µL PBS control, or 100µL PBS containing 25 mgs/kg cyclophosphamide intra-peritoneally. Four days later, mice were also given either 300µg anti-PD1 or vehicle control. A total of 4 doses of PD1 was given on day 0, 5, 10, and 14. Statistical significance was determined using a linear mixed-effect model. Err.=SEM. D, fold change in mouse weight from C. Err=SD. E. Intra-tumoral ratios of CD3+CD8a+ to CD3+CD4+FoxP3+ at the end of the experiment. Err.=SEM.

upplementary Figure 1 - Wnt5A Decreases Proliferation Specifically in Tumors Via the Recruitment of MDSCs

Supplementary Figure 1

Figure Legends for Supplemental Data

Supplementary Figure 4 - rWnt5A and Myeloid-Wnt5A Promotes an Immunosuppressive TME in Peripheral Blood and Lungs in vivo

Supplemental Table 1. Antibodies used.

Purpose: We have shown that the aged microenvironment increases melanoma metastasis, and decreases response to targeted therapy, and here we queried response to anti-PD1.Experimental Design: We analyzed the relationship between age, response to anti-PD1, and prior therapy in 538 patients. We used mouse models of melanoma, to analyze the intratumoral immune microenvironment in young versus aged mice and confirmed our findings in human melanoma biopsies.Results: Patients over the age of 60 responded more efficiently to anti-PD-1, and likelihood of response to anti-PD-1 increased with age, even when we controlled for prior MAPKi therapy. Placing genetically identical tumors in aged mice (52 weeks) significantly increased their response to anti-PD1 as compared with the same tumors in young mice (8 weeks). These data suggest that this increased response in aged patients occurs even in the absence of a more complex mutational landscape. Next, we found that young mice had a significantly higher population of regulatory T cells (Tregs), skewing the CD8+:Treg ratio. FOXP3 staining of human melanoma biopsies revealed similar increases in Tregs in young patients. Depletion of Tregs using anti-CD25 increased the response to anti-PD1 in young mice.Conclusions: While there are obvious limitations to our study, including our inability to conduct a meta-analysis due to a lack of available data, and our inability to control for mutational burden, there is a remarkable consistency in these data from over 500 patients across 8 different institutes worldwide. These results stress the importance of considering age as a factor for immunotherapy response. Clin Cancer Res; 24(21); 5347–56. ©2018 AACR.See related commentary by Pawelec, p. 5193

Supplementary Figure 6 - rWnt5A Does Not Promote Treg Migration in vitro

Supplementary Figure 5 - Myeloid Wnt5A Does Not Influence CXCR2 Expression on MDSCs

Supplementary Figure 3 - Effects of Myeloid Wnt5A Knockdown on Apoptosis, and Wnt5A Expression in Cell lines and Tumor Lysates

Supplementary Figure 3

Supplementary Figures 1-5, Table 1 from p38 Kinase Is Crucial for Osteopontin-Induced Furin Expression That Supports Cervical Cancer Progression

Metastatic dissemination remains a significant barrier to successful therapy for melanoma. Wnt5A is a potent driver of invasion in melanoma and is believed to be secreted from the tumor microenvironment (TME). Our data suggest that myeloid-derived suppressor cells (MDSC) in the TME are a major source of Wnt5A and are reliant upon Wnt5A for multiple actions. Knockdown of Wnt5A specifically in the myeloid cells demonstrated a clear decrease in Wnt5A expression within the TME in vivo as well as a decrease in intratumoral MDSC and regulatory T cell (Treg). Wnt5A knockdown also decreased the immunosuppressive nature of MDSC and decreased expression of TGFβ1 and arginase 1. In the presence of Wnt5A-depleted MDSC, tumor-infiltrating lymphocytes expressed decreased PD-1 and LAG3, suggesting a less exhausted phenotype. Myeloid-specific Wnt5A knockdown also led to decreased lung metastasis. Tumor-infiltrating MDSC from control animals showed a strong positive correlation with Treg, which was completely ablated in animals with Wnt5A-negative MDSC. Overall, our data suggest that while MDSC contribute to an immunosuppressive and less immunogenic environment, they exhibit an additional function as the major source of Wnt5A in the TME. Significance: These findings demonstrate that myeloid cells provide a major source of Wnt5A to facilitate metastatic potential in melanoma cells and rely on Wnt5A for their immunosuppressive function.

Older patients with melanoma (>50 years old) have poorer prognoses and response rates to targeted therapy compared with young patients ( Significance: These data show that melanoma cells take up lipids from aged fibroblasts, via FATP2, and use them to resist targeted therapy. The response to targeted therapy is altered in aged individuals because of the influences of the aged microenvironment, and these data suggest FATP2 as a target to overcome resistance. See related commentary by Montal and White, p. 1255.. This article is highlighted in the In This Issue feature, p. 1241

“Aged” melanoma patients (>55 years old) have poorer prognosis and reduced response rates to targeted therapy relative to “young” patients ( Citation Format: Gretchen Marie Alicea, Vito W. Rebecca, Aaron Goldman, Mitchell Fane, Reeti Behera, Marie Webster, Brett Ecker, Ian Blair, David Speicher, Zachary Schug, Ashani Weeraratna. The aged tumor microenvironment promotes melanoma metabolic plasticity and therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5086.

Purpose: We have shown that the aged microenvironment increases melanoma metastasis, and decreases response to targeted therapy, and here we queried response to anti-PD1. Experimental Design: We analyzed the relationship between age, response to anti-PD1, and prior therapy in 538 patients. We used mouse models of melanoma, to analyze the intratumoral immune microenvironment in young versus aged mice and confirmed our findings in human melanoma biopsies. Results: Patients over the age of 60 responded more efficiently to anti-PD-1, and likelihood of response to anti-PD-1 increased with age, even when we controlled for prior MAPKi therapy. Placing genetically identical tumors in aged mice (52 weeks) significantly increased their response to anti-PD1 as compared with the same tumors in young mice (8 weeks). These data suggest that this increased response in aged patients occurs even in the absence of a more complex mutational landscape. Next, we found that young mice had a significantly higher population of regulatory T cells (Tregs), skewing the CD8+:Treg ratio. FOXP3 staining of human melanoma biopsies revealed similar increases in Tregs in young patients. Depletion of Tregs using anti-CD25 increased the response to anti-PD1 in young mice. Conclusions: While there are obvious limitations to our study, including our inability to conduct a meta-analysis due to a lack of available data, and our inability to control for mutational burden, there is a remarkable consistency in these data from over 500 patients across 8 different institutes worldwide. These results stress the importance of considering age as a factor for immunotherapy response. Clin Cancer Res; 24(21); 5347–56. ©2018 AACR. See related commentary by Pawelec, p. 5193

Autophagy mediates resistance to various anticancer agents. In melanoma, resistance to targeted therapy has been linked to expression of Wnt5A, an intrinsic inhibitor of β-catenin, which also promotes invasion. In this study, we assessed the interplay between Wnt5A and autophagy by combining expression studies in human clinical biopsies with functional analyses in cell lines and mouse models. Melanoma cells with high Wnt5A and low β-catenin displayed increased basal autophagy. Genetic blockade of autophagy revealed an unexpected feedback loop whereby knocking down the autophagy factor ATG5 in Wnt5Ahigh cells decreased Wnt5A and increased β-catenin. To define the physiologic relevance of this loop, melanoma cells with different Wnt status were treated in vitro and in vivo with the potent lysosomotropic compound Lys05. Wnt5Ahigh cells were less sensitive to Lys05 and could be reverted by inducing β-catenin activity. Our results suggest the efficacy of autophagy inhibitors might be improved by taking the Wnt signature of melanoma cells into account. Cancer Res; 77(21); 5873–85. ©2017 AACR.

Cancer cell invasion from primary tumors is mediated by a complex interplay between cellular adhesions, actomyosin-driven contractility, and the physical characteristics of the extracellular matrix (ECM). Here, we incorporate a mechanochemical free-energy-based approach to elucidate how the two-way feedback loop between cell contractility (induced by the activity of chemomechanical interactions such as Ca2+ and Rho signaling pathways) and matrix fiber realignment and strain stiffening enables the cells to polarize and develop contractile forces to break free from the tumor spheroids and invade into the ECM. Interestingly, through this computational model, we are able to identify a critical stiffness that is required by the matrix to break intercellular adhesions and initiate cell invasion. Also, by considering the kinetics of the cell movement, our model predicts a biphasic invasiveness with respect to the stiffness of the matrix. These predictions are validated by analyzing the invasion of melanoma cells in collagen matrices of varying concentration. Our model also predicts a positive correlation between the elongated morphology of the invading cells and the alignment of fibers in the matrix, suggesting that cell polarization is directly proportional to the stiffness and alignment of the matrix. In contrast, cells in nonfibrous matrices are found to be rounded and not polarized, underscoring the key role played by the nonlinear mechanics of fibrous matrices. Importantly, our model shows that mechanical principles mediated by the contractility of the cells and the nonlinearity of the ECM behavior play a crucial role in determining the phenotype of the cell invasion.

Purpose: Aging is a poor prognostic factor for melanoma. We have shown that melanoma cells in an aged microenvironment are more resistant to targeted therapy than identical cells in a young microenvironment. This is dependent on age-related secreted factors. Klotho is an age-related protein whose serum levels decrease dramatically by age 40. Most studies on klotho in cancer have focused on the expression of klotho in the tumor cell. We have shown that exogenous klotho inhibits internalization and signaling of Wnt5A, which drives melanoma metastasis and resistance to targeted therapy. We investigate here whether increasing klotho in the aged microenvironment could be an effective strategy for the treatment of melanoma. Experimental Design: PPARγ increases klotho levels and is increased by glitazones. Using rosiglitazone, we queried the effects of rosiglitazone on Klotho/Wnt5A cross-talk, in vitro and in vivo, and the implications of that for targeted therapy in young versus aged animals. Results: We show that rosiglitazone increases klotho and decreases Wnt5A in tumor cells, reducing the burden of both BRAF inhibitor–sensitive and BRAF inhibitor–resistant tumors in aged, but not young mice. However, when used in combination with PLX4720, tumor burden was reduced in both young and aged mice, even in resistant tumors. Conclusions: Using glitazones as adjuvant therapy for melanoma may provide a new treatment strategy for older melanoma patients who have developed resistance to vemurafenib. As klotho has been shown to play a role in other cancers too, our results may have wide relevance for multiple tumor types. Clin Cancer Res; 23(12); 3181–90. ©2017 AACR.

Cancer is a disease of ageing. Clinically, aged cancer patients tend to have a poorer prognosis than young. This may be due to accumulated cellular damage, decreases in adaptive immunity, and chronic inflammation. However, the effects of the aged microenvironment on tumour progression have been largely unexplored. Since dermal fibroblasts can have profound impacts on melanoma progression, we examined whether age-related changes in dermal fibroblasts could drive melanoma metastasis and response to targeted therapy. Here we find that aged fibroblasts secrete a Wnt antagonist, sFRP2, which activates a multi-step signalling cascade in melanoma cells that results in a decrease in β-catenin and microphthalmia-associated transcription factor (MITF), and ultimately the loss of a key redox effector, APE1. Loss of APE1 attenuates the response of melanoma cells to DNA damage induced by reactive oxygen species, rendering the cells more resistant to targeted therapy (vemurafenib). Age-related increases in sFRP2 also augment both angiogenesis and metastasis of melanoma cells. These data provide an integrated view of how fibroblasts in the aged microenvironment contribute to tumour progression, offering new possibilities for the design of therapy for the elderly.

Deregulation of signal transducer and activator of transcription (STAT)-3 signaling plays crucial role in oncogenesis of various cancers. However, the molecular mechanism by which osteopontin (OPN), a chemokine-like extracellular matrix-associated protein, regulates STAT3 activation that leads to tumor progression and inhibits apoptosis in breast cancer cells is not well understood. In this study, we for the first time report that OPN upregulates alphavbeta3 integrin-mediated Janus kinase 2 (JAK2) phosphorylation and STAT3 activation in breast cancer (MDA-MB-468 and MCF-7) cells. Pretreatment of cells with JAK2 inhibitor (AG 490) suppresses OPN-induced STAT3 phosphorylation, its nuclear localization and DNA binding indicating that JAK2 is involved in this process. Transfection of cells with wild-type (wt) STAT3 enhanced whereas mutant STAT3 (STAT3 Y705F) suppressed OPN-induced breast tumor cell migration. Treatment of cells with OPN followed by staurosporine (STS) showed that OPN protects the cells from STS-induced apoptosis. Moreover, transfection of cells with wt STAT3 upregulates whereas STAT3 Y705F downregulates Bcl2 and cyclin D1 expressions in response to OPN. Interestingly, STAT3-overexpressing cells when injected to non-obese diabetic/severe combined immunodeficiency mice followed by OPN treatment, the mice developed enhanced tumor growth as compared with STAT3 Y705F-injected mice or mice injected with OPN alone. The levels of Bcl2 and cyclin D1 in wt STAT3 tumors were significantly higher than controls. Clinical specimen analysis revealed that increased OPN and pSTAT3 expressions correlate with enhanced breast tumor progression. Thus, targeting OPN and its regulated STAT3 signaling could be a potent therapeutic approach and understanding these mechanisms may form the basis of new therapeutic regimen for the management of breast cancer.

Osteopontin (OPN) is a chemokine like phosphorylated glycoprotein that plays important role in cancer progression. Extensive research from various laboratories has demonstrated the likely role of OPN in regulating the cell signaling that ultimately controls tumor growth and metastasis. Several earlier reports indicated that OPN is associated with various cancers; but its functional role in carcinogenesis is still not well defined. Besides the role of OPN in tumor biology, several studies have demonstrated the pathophysiological role of OPN in diverse biological events. This review will focus on recent advances in understanding the molecular mechanism by which OPN regulates a series of signaling cascades through activation of various kinases and transcription factors that ultimately control the expression of downstream effector genes, which contribute to tumor progression and angiogenesis in vitro and animal models. We will also provide evidences that suggest the enhanced expression of OPN is not only associated with several tumor types, but its level of expression is directly correlated to various stages of the clinical specimens of breast and prostate cancers. These studies may be useful for identifying novel OPN-based therapeutic approach for the treatment of cancer.

Tumor-associated macrophages (TAM) contribute to all aspects of tumor progression. Use of CSF1R inhibitors to target TAM is therapeutically appealing, but has had very limited anti-tumor effects. Here, we have identified the mechanism that limited the effect of CSF1R targeted therapy. We demonstrated that carcinoma-associated fibroblasts (CAF) are major sources of chemokines that recruit granulocytes to tumors. CSF1 produced by tumor cells caused HDAC2-mediated downregulation of granulocyte-specific chemokine expression in CAF, which limited migration of these cells to tumors. Treatment with CSF1R inhibitors disrupted this crosstalk and triggered a profound increase in granulocyte recruitment to tumors. Combining CSF1R inhibitor with a CXCR2 antagonist blocked granulocyte infiltration of tumors and showed strong anti-tumor effects.

Breast cancer is one of the most common malignant tumors among females worldwide and remains a leading cause of cancer-related mortality. Due to the heterogeneous clinical nature of breast cancer, it is necessary to identify new biomarkers that are associated with tumor growth, angiogenesis and metastasis. Osteopontin (OPN) and cyclooxygenase-2 (COX-2) are known to be overexpressed in invasive breast cancer and their overexpression is associated with aggressive histological and clinical features. The present study assessed OPN and COX-2 expression in various subtypes of breast cancer. The expression of OPN and COX-2 was analyzed using immunohistochemistry (IHC) in a cohort of 67 invasive ductal breast carcinoma patients. The statistical analysis was performed using standard statistical software SPSS version 18.0. The associations between OPN and COX-2 and the human epidermal growth factor receptor type 2 (HER2)-overexpressing and non-HER2-overexpressing subtypes were evaluated using the Mann-Whitney U test. The mean OPN level was significantly higher in the HER2-overexpressing subtype compared with the non-HER2-overexpressing subtype. Furthermore, the mean COX-2 expression levels were higher in the HER2-overexpressing subtype compared with the luminal A, luminal B or triple-negative groups. It is well known that carcinomas overexpressing HER2/neu have a worse prognosis than luminal tumors. Hence, it may be hypothesized that an elevated expression of OPN and COX-2 in a HER2-overexpressing subtype may contribute to a more aggressive behavior and be used as diagnostic and prognostic markers in breast cancer.

Nature 532, 250–254 (2016); doi:10.1038/nature17392 In Fig. 5a of this Letter, the labels PBS and PLX4720 were inadvertently reversed. The corrected Fig. 5a is shown in Fig. 1 of this Corrigendum.

Osteopontin (OPN), a cytokine like ECM associated member of Small Integrin Binding LIgand N-linked Glycoprotein (SIBLING) family of protein plays an important role in determining the metastatic potential of many cancers. The function of OPN in various pathophysiological conditions, especially in cancer indicated that the variation in posttranslational modification generate different functional forms that might alter its normal physiological functions. Recent data indicated that OPN regulates tumor growth through induction of pro-angiogenic and metastatic genes like COX-2, and VEGF expressions and activation of matrix metalloproteinase (MMP) in cancer cells. The exact role of stromaand tumor-derived OPN in regulation of tumor growth and angiogenesis in various cancers is not well understood. Therefore, it is important to delineate the mechanism by which both tumor and stroma-derived OPN control the cell migration and tumor growth. p70S6 kinase, STAT3 and VEGF are directly involved in regulation of breast tumor growth and angiogenesis. But, the mechanism by which OPN regulates p70S6 kinase and STAT3 activation and VEGF expression leading to breast cancer cell migration, tumor growth and angiogenesis are not well defined. We have recently shown that OPN induces p70S6 kinase phosphorylation in a site specific manner. Interestingly, OPN has no effect on mTOR phosphorylation, but overexpression of mTOR does not regulate OPN-induced phosphorylation of p70S6 kinase. Overexpression of mTOR/p70S6 kinase suppresses OPNinduced ICAM-1 expression, while treatment with rapamycin enhances OPN-induced ICAM-1 expression. Our recent data also indicated that OPN upregulates JAK2 dependent STAT3 activation in breast cancer cells. Wild type STAT3 enhanced whereas mutant STAT3 suppressed OPN-induced breast tumor cell migration. Cells overexpressing STAT3 upregulate whereas mutant STAT3 downregulate OPN-induced tumor growth leading to

Cancer is an extremely complex disease and most cancer treatments are limited to chemotherapy, radiation and surgery. The progression of tumours towards malignancy requires the interaction of various cytokines, growth factors, transcription factors and effector molecules. Osteopontin is a cytokine-like, calcium-binding, extracelular-matrix- associated member of the small integrin-binding ligand, N-linked glycoprotein (SIBLING) family of proteins. It plays an important role in determining the oncogenic potential of various cancers. The role of osteopontin in various pathophysiological conditions suggests that the alteration in post-translational modification result in different functional forms that might change its normal physiological functions.Osteopontin -based anticancer therapy, which may provide a new insight for the effective management of cancer.A better understanding of the signalling mechanism by which osteopontin promotes tumourigenesis may be useful in crafting novel osteopontin -based anticancer therapy. The role of osteopontin in promoting cancer progression is the subject of in depth investigation and thus targeting osteopontin might be a suitable therapeutic approach for the treatment of cancer.

p38 kinases activated by growth factors, hormones, and environmental stresses exert diverse functions in regulating normal and malignant cell pathophysiology. Enhanced levels of activated p38 isoforms have been linked with poor prognosis in breast cancer, although the mechanistic basis for this association is poorly understood. In this study, we report that p38 activation in cervical cancer cells is driven by osteopontin (OPN), an extracellular matrix–associated cytokine that drives invasive progression. OPN regulates CD44-mediated p38 phosphorylation that induces NF-κB activation and NF-κB–dependent expression of furin, an extracellular protease implicated in human papilloma virus (HPV) processing that enhances cervical cancer cell motility. OPN induces CD44-mediated MKK3/6 phosphorylation which in turn phosphorylates p38 in these cells. OPN-induced furin expression and cell motility was impeded by blockades to MKK3/6, p38α/β or NF-κB signaling. In a mouse xenograft model of human cervical cancer, tumor growth was enhanced by OPN overexpression and blocked by short hairpin RNA (shRNA)–mediated OPN silencing. Furin overexpression similarly augmented tumor growth in the model, whereas blocking MKK3/6, p38, or furin reduced OPN-induced cervical tumor growth. Analysis of clinical specimens revealed that enhanced expression of OPN, phosphorylated NF-κB, p65, and furin correlated with cervical cancer progression, further strengthening the in vitro and in vivo results. In summary, our findings offer a proof of concept for targeting OPN and its downstream p38 signaling as a novel therapeutic strategy to manage cervical cancer. Cancer Res; 70(24); 10381–91. ©2010 AACR.

Melanoma is an aggressive disease. Although about 13% of melanoma cases are diagnosed at metastatic stage, the 5-year survival rate for these patients is 16%. We have previously shown that metastatic melanoma cells express high levels of Wnt5a. Wnt5a is a member of the Wnt family of proteins, which play an important role during development and tumorigenesis. In melanoma, Wnt5a signaling is mediated by an autocrine loop that also modulates the activity of midkine. Midkine is a 16kDa protein that is elevated in many different cancers. Overexpression of midkine promotes the growth, migration, survival and angiogenic capability of the tumors. However, the molecular mechanisms that regulate the activity of midkine are unknown, especially in metastatic melanoma. We asked whether Wnt5a can positively regulate the functions of midkine to promote the progression of metastatic melanoma. To address this, we analyzed melanoma cells for midkine expression and observed that Wnt5a high melanoma cells also express high levels of midkine. Further, an increase in Wnt5a signaling by treatment with recombinant Wnt5a led to an increased midkine signaling. By performing 3D spheroid assays, we observed that higher expression of midkine is correlated with an increased metastatic ability of the cells. The expression of midkine also correlated with an increased resistance to BRAF inhibitors in BRAF V600E mutated melanoma. This indicates that midkine may signal through MAPK pathway to affect invasion and drug resistance in metastatic melanoma. Developing adjuvant therapies targeting midkine can prolong the overall survival of patients with metastatic melanoma. Citation Format: Amanpreet Kaur, Michael O'Connell, Marie Webster, Reeti Behera, Vanessa Dang, Abibatou Ndoye, Ashani Weeraratna. Midkine as a potential target for combating drug resistance and invasion in melanoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5092. doi:10.1158/1538-7445.AM2015-5092

Melanoma is the most aggressive type of skin cancer and the leading cause of death from skin disease. With increasing incidence of the disease, it is crucial to further investigate the cellular mechanisms and molecular pathways that lead to invasion, metastasis, and drug resistance. Recent studies have revealed that high autophagy correlates with melanoma tumor aggressiveness and poor survival in clinical samples, as it is a common mechanism of resistance to therapy. Autophagy inhibition leads to reduced levels in Wnt5A in a breast cancer model, suggesting a cross-talk of Wnt5A and autophagy in cancer. β catenin, a mediator of canonical Wnt signaling, has been shown to act as a negative regulator of both basal and induced autophagy in a colorectal cancer model. Our laboratory showed that high levels of Wnt5A correlate with increased invasion and metastasis in melanoma and that Wnt5A downregulates β catenin; therefore, we hypothesize that autophagy might drive invasion and metastasis in aggressive melanoma through the regulation of Wnt signaling. To study the role of autophagy in Wnt5A-mediated melanoma invasion, we inhibited autophagy in highly invasive melanoma cells using lentivirus-mediated shATG5 knockdown or hydroxychloroquine and evaluated the effects of autophagy inhibition on Wnt5A expression, β catenin, and invasion using 3D spheroid models. Analysis of autophagy flux confirms that highly invasive melanoma cells have high autophagy compared to non-invasive cell lines. The inhibition of autophagy by hydroxychloroquine or shATG5 both resulted in significant decrease in invasion. By western blot analysis, we also observed a decrease in Wnt5A in these cells. These results demonstrate that autophagy inhibition in highly invasive melanoma leads to decrease in invasion in a 3D model that mimics the tumor microenvironment of melanoma. Further dissection of the molecular mechanisms that are involved in this process will enable the identification of novel autophagy targets in aggressive melanoma. Citation Format: Abibatou Ndoye, Anna Budina, Marie Webster, Amanpreet Kaur, Reeti Behera, Maureen Murphy, Ashani T. Weeraratna. Role of autophagy in Wnt5A-mediated melanoma invasion and metastasis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2906. doi:10.1158/1538-7445.AM2015-2906

Background: Mortality rates due to melanoma are continuously increasing. Specifically, in older patients, melanoma is very aggressive and has a poor prognosis, compared to the young. Therefore, there is an urgent need to understand the underlying molecular mechanisms behind this age-related aggression. The expression level of klotho, an emerging tumor suppressor, declines with the progression of age and is associated with several pathologies related to human aging. A previous study from our group has demonstrated that loss of klotho in melanoma cells is associated with enhanced melanoma cell motility by decreasing the ability of melanoma cells to internalize Wnt5A, a non-canonical Wnt protein, known to be one of the drivers of melanoma metastasis. Therefore, we hypothesize that the loss of Klotho in aging microenvironment contributes to enhanced Wnt5A signaling and ultimately results in age-related melanoma aggression. Methods: In order to study the effects of aged microenvironment on melanoma cells, we have obtained and cultured normal skin fibroblasts from aged (55-65 years old) and young donors (25-35 years old). The expression levels of klotho and Wnt5A in these fibroblasts were analyzed by immunoblot, immunofluorescence and real time-PCR assays. We examined melanoma cell/ fibroblast co-cultures and artificial skin reconstructs made with these fibroblasts to understand the age-related effects of tumor microenvironment on the disease progression. We also used immunohistochemistry technique to examine the expression levels of Klotho and Wnt5A in these artificial skin reconstructs and in the paraffin-embedded skin sections obtained from young and old melanoma patients. Results: Our western blot and real-time PCR results of the young vs. old fibroblasts show that klotho expression level is lost with progression of age. Analysis of artificial skin reconstructs made using skin fibroblasts isolated from aged donors demonstrate induced invasion of melanoma cells to a much greater extent than those cultured from young donors. We also analyzed these skin reconstructs for the expression levels of Klotho and Wnt5A, using immunohistochemistry technique and the results confirm that Klotho is decreased in aged fibroblasts. Furthermore, we also found that the loss of Klotho in the aged microenvironment translated to a loss of Klotho in melanoma cells. Our western blot results also suggest that loss of Klotho in the aging microenvironment enhances Wnt5A internalization and signaling and this promotes tumor metastasis. Our immunohistochemistry results using patient samples further extend our in vitro findings and support our hypothesis that Klotho plays pivotal role in age-related melanoma progression. Significance: These results for the first time demonstrate a correlation between age-related melanoma progression and the loss of klotho level. In addition, these findings provide a molecular explanation of age-related melanoma aggression. Citation Format: Reeti Behera, Amanpreet Kaur, Katie Marchbank, Vanessa Dang, Marie Webster, Xiaowei Xu, Ashani T. Weeraratna. Role of Klotho in age-related melanoma progression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1556. doi:10.1158/1538-7445.AM2015-1556

Background: Klotho, an emerging tumor suppressor, was originally identified as an anti-aging gene. The klotho expression level declines with the progression of age and is associated with several pathologies related to human aging. Mortality rates due to melanoma are continuously increasing. Specifically, in older patients, melanoma is very aggressive and has a very poor prognosis, compared to the young. Therefore, there is an urgent need to understand the underlying molecular mechanisms behind this age-related aggression. A previous study from our group has demonstrated that loss of klotho in melanoma cells is associated with enhanced melanoma cell motility by decreasing the ability of melanoma cells to internalize Wnt5A, a non-canonical Wnt protein, known to be a driver of melanoma metastasis. Therefore, we hypothesize that the loss of Klotho in aging microenvironment contributes to enhanced Wnt5A signaling, ultimately resulting in age-related melanoma aggression. Methods: In order to study the effects of aged microenvironment on melanoma cells, we have obtained and cultured normal skin fibroblasts from aged (55-65 years old) and young donors (25-35 years old) from the Baltimore Longitudinal Study of Aging (BLSA). The expression levels of klotho and Wnt5A in these fibroblasts were analyzed by immunoblot, immunofluorescence and real time-PCR assays. We examined melanoma cell/ fibroblast co-cultures and artificial skin reconstructs made with these fibroblasts to understand the age-related effects of tumor microenvironment on the disease progression. We also used immunohistochemistry technique to examine the expression levels of Klotho and Wnt5A in these artificial skin reconstructs and in the paraffin-embedded skin sections obtained from young and old melanoma patients. Results: Our western blot and real-time PCR results of the young vs. old fibroblasts show that klotho expression level is lost and Wnt5A expression is gained with progression of age. Analysis of artificial skin reconstructs made using skin fibroblasts isolated from aged donors demonstrate induced invasion of melanoma cells to a much greater extent than those cultured from young donors. We also analyzed these skin reconstructs for the expression levels of Klotho and Wnt5A, using immunohistochemistry technique and our results confirm that Klotho is decreased in aged fibroblasts, furthermore, we also found that the loss of Klotho in the aged microenvironment also gets translated to a loss of Klotho in melanoma cells, and a gain of Wnt5A. Our immunohistochemistry results with the patient samples further extend our in vitro findings and support our hypothesis that Klotho-Wnt5A cross talk plays pivotal role in age-related melanoma progression. Significance: These results for the first time demonstrate a correlation between age-related melanoma progression and the loss of klotho and gain in Wnt5A expression levels in the aging tumor microenvironment. In addition, these findings provide a molecular explanation of age-related melanoma aggression. Citation Format: Reeti Behera, Katie Marchbank, Amanpreet Kaur, Vanessa Dang, Marie Webster, Michael O'Connell, Xiaowei Xu, Ashani Weeraratna. Crosstalk between klotho and wnt5A drives age-related melanoma progression. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr A11.