Peter J. Vanveldhuizen

Gain of Oncogenic Function of p53 Mutants Induces Invasive Phenotypes in Human Breast Cancer Cells by Silencing CCN5/WISP-2

CCN5/WISP-2 is overexpressed in noninvasive breast cancer cells and tissue samples, whereas its expression is minimal or undetected in invasive conditions. CCN5/WISP-2 has been considered as an antiinvasive gene because CCN5/WISP-2 silencing augments the invasive phenotypes in vitro. However, the mechanism of silencing of CCN5 during the progression of the disease has been elusive. Because p53 mutations are associated with breast cancer progression and have been shown to correlate inversely with CCN5/WISP-2 expression in other cancer cell types, the objective of this study was to explore whether p53 mutants suppress CCN5 expression in breast tumor cells resulting in the progression of this disease. We found CCN5 expression is inversely correlated with the mutational activation of p53 in human breast tumor cells. The ectopic expression of p53 mutants in ER-positive noninvasive breast tumor cells silenced the CCN5/WISP-2 expression and enhanced invasive phenotypes, including the induction of morphologic changes from the epithelial-to-mesenchymal type along with the alterations of hallmark proteins of these cell types and an augmentation of the migration of these cells. The suppression of CCN5 by the p53 mutants can be nullified by estrogen signaling in these cells through the transcriptional activation of the CCN5 gene. Moreover, the invasive changes can be imitated by blocking the CCN5/WISP-2 expression through RNA interference or can be reversed by the addition of CCN5/WISP-2 recombinant protein in the culture. Thus, these studies suggest that CCN5 inactivation could be an essential molecular event for p53 mutant-induced invasive phenotypes.

Gemcitabine and Cisplatin for Patients with Metastatic or Recurrent Esophageal Carcinoma: A Southwest Oncology Group Study

Purpose: Experimental data, both in vivo and in vitro, suggest that the combination of gemcitabine and cisplatin acts synergistically. Within the Southwest Oncology Group, we designed a Phase II trial to test this chemotherapy combination for patients with esophageal cancer. Experimental design: Patients with metastatic or recurrent esophageal cancer were treated with gemcitabine 1000 mg/m2 on days 1, 8, and 15, and cisplatin 100 mg/m2 on day 15. Cycles were repeated every 28 days. The statistical endpoint was overall survival. Results: Sixty-four eligible patients were accrued from 37 institutions. Twenty-six percent of patients had prior chemotherapy. The treatment was generally well-tolerated, with the most common toxicity being neutropenia in 31% of patients. All 64 patients have died. Survival at 3 months was 81%, and at 1 year was 20%. Median survival was 7.3 months. Conclusions: This regimen is tolerable palliative option for patients with metastatic esophageal cancer.

Leiomyosarcoma of the inferior vena cava: a case report and review of the literature

A 68-year-old white female presented with two years of progressively worsening dyspnea. Echocardiography revealed a large right atrial mass and partial obstruction of the inferior vena cava. Further imaging revealed a cystic dense mass in the inferior vena cava and right atrium. Immunohistochemical stains were consistent with leiomyosarcoma. Intraoperatively, the tumor was noted to originate from the posterior aspect of the inferior vena cava. The patient underwent successful resection of the mass. Adjuvant radiation therapy was completed. The patients dyspnea gradually improved and she continues to remain disease free five years post-resection.

2-Methoxyestradiol Inhibits Barrett's Esophageal Adenocarcinoma Growth and Differentiation through Differential Regulation of the β-Catenin–E-Cadherin Axis

The purpose of this study was to evaluate whether 2-methoxyestradiol (2-ME2), a promising anticancer agent, modulates Barretts esophageal adenocarcinoma (BEAC) cell growth and behavior through a cellular pathway involving β-catenin in partnership with E-cadherin, which seems to play a critical role in the induction of antitumor responses in cancer cells. We found that 2-ME2 markedly reduced the BEAC cell proliferation through regulating apoptotic machinery such as Bcl-2 and Bax. It may nullify the aggressive behavior of the cells by reducing the migratory behavior. Expressions of β-catenin and E-cadherin and binding of these two proteins is activated in a 2-ME2–dependent fashion in Bic-1 cells. Moreover, overexpressions of these two proteins may be due to the stabilization of these proteins by 2-ME2. We found that 2-ME2–induced antimigratory effects are mediated through the β-catenin–E-cadherin signaling pathways. In view of these results, we determined whether 2-ME2 reduces BEAC tumor growth. Administration of 2-ME2 significantly decreased the growth of BEAC cells xenografted on the flank of nude mice. The evidence presented points out that the effect of 2-ME2 on β-catenin–orchestrated signal transduction plausibly plays a multifaceted functional role to inhibit the proliferation and cell migration of 2-ME2–treated malignant cells and it could be a potential candidate in novel treatment strategies for Barretts esophageal adenocarcinoma. Mol Cancer Ther; 9(3); 523–34

Abstract B12: Macrophage inhibitory cytokine-1 as a potential biomarker for racial disparity in prostate cancer

Macrophage inhibitory cytokine-1 (MIC-1) has drawn significant attention due to its association with the development and progression of prostate cancer (PCa). Recent studies have projected MIC-1 as a potential biomarker for various disease conditions including PCa. Given evidence for more aggressive disease among African American (AA) men, we aimed to investigate if MIC-1 was differentially expressed among AA and Caucasian men. We measured serum MIC-1 levels by sandwich ELISA in samples collected during the diagnosis of PCa (pre-surgical). Our data consists of information on 40 Caucasian and 40 AA men between the ages of 43 and 75 years (Median = 60 years). Based on the analysis of log transformation of the data, significant differences among the two races were found, with AA having higher MIC-1 expression (Median 1220.4 versus 790.8, p=0.0001), Gleason scores (Median 7 versus 6, p=0.0009) and PSA (Median 6.72 versus 6.35 ng/ml, p = 0.04) than Caucasians. No differences in age or pathological stage of disease were observed between groups (p > 0.05). Higher levels of MIC-1 and Gleason scores were associated (p Citation Format: Dev Karan, Seema Dubey, Jo Wick, Ossama Tawfik, Guru Sonpavde, Peter VanVeldhuizen. Macrophage inhibitory cytokine-1 as a potential biomarker for racial disparity in prostate cancer. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr B12.

Abstract 5654: Docetaxel followed by temsirolimus suppresses mTOR pathway and can overcome PI3K / AKT over activation mechanism of resistance in lung cancer cell line.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Background: Mammalian target of rapamycin (mTOR) is a downstream regulatory protein of PI3K/AKT signal transduction pathway. The activation of cell surface receptors including IGF-1R (Insulin-Growth Factor-1Receptor) and EGFR (Epidermal Growth Factor Receptor) signals through PI3K/AKT pathway and is essential in cell proliferation, angiogenesis and anti-apoptosis process. Over activation of PI3K/AKT is a potential mechanism of resistance to mTOR inhibitors. mTOR inhibition could be a potential novel strategy in the treatment of lung cancer. Docetaxel (D) is commonly used in lung cancer treatment. Previously, we demonstrated that the sequence of D followed by mTOR inhibitor temsirolimus (T) in lung cancer cell lines (LCCL) had increased suppression of cell proliferation as compared to reverse sequence of T→D. The reason for this difference in decrease in proliferation effect is unclear. We hypothesized that D→T sequence can suppress the over activation of PI3K/AKT mechanism of resistance. We studied the expression of pmTOR, AKT and PI3K expression in lung cancer cell lines treated with different sequences of D and T and at different time points. Methods: Adenocarcinoma LCCL H2122 and H1437 were treated with T 1000nM or D 100nM for 24, 48 and 72h. We then treated both LCCL with D exposed for 24h followed by addition of T and the reverse sequence in both LCCL and prepared cell lysate at 24, 48 and 72h time points. We determined the expression of pmTOR, pAKT and PI3K by western blot using antibody from Cell Signaling. Results: T alone suppressed pmTOR after 24h but not at 48 and 72h in both LCCL. AKT was not suppressed. PI3K increased after 48h in both LCCL. The sequence of D→T suppressed expression of pmTOR and decreased expression of pAKT and PI3K at 48 and 72h in the H1437. We observed suppression of mTOR and PI3K but not AKT in the H2122. The opposite sequence of T→D did not suppress the expression of pmTOR and did not suppress the expression of pAKT and PI3K. Conclusion: The combination of D → T has synergistic inhibition of mTOR and it is able to suppress the over activation of AKT/PI3K pathway when compared with reverse sequence. This suggests that sequence of D→T can overcome the over activation of PI3K/AKT mechanism of resistance and it would be the ideal treatment sequence when using D in combination with mTOR inhibitor in the treatment of lung cancer. Expression of AKT/PI3K could be used as a biomarker of response to this regimen. Citation Format: Chao H. Huang, Peter J. VanVeldhuizen, Stephen K. Williamson, Ayten Gadashova, Faris Farassati. Docetaxel followed by temsirolimus suppresses mTOR pathway and can overcome PI3K / AKT over activation mechanism of resistance in lung cancer cell line. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5654. doi:10.1158/1538-7445.AM2013-5654

Abstract 2007: Epigenetic reactivation of CCN5/WISP2 by combined effect of green tea polyphenol and epigenetic modulators in highly aggressive breast cancer cells

CCN5/WISP-2 has been considered as an antiinvasive gene because CCN5/WISP-2 silencing augments the invasive phenotypes in vitro. One of the major functions of the CCN5 protein is to block aggressive behavior, such as the mesenchymal-to-epithelial transition (MET) of cancer cells. CCN5/WISP-2 is constitutively expressed in less aggressive human breast cancer cells, whereas its expression is undetected in the highly aggressive breast cancer cells. Dietary green tea polyphenol, (−)-epigallocatechin-3-gallate (EGCG), is believed to be an anticancer agent in part through its regulation of epigenetic processes. Our studies were aimed to address the epigenetic mechanisms of CCN5 reactivation by EGCG in highly aggressive breast cancer cells. In our current studies, we found that EGCG can reactivate CCN5 expression in highly aggressive breast cancer cell line (MDA-MB-231) and augments mesenchymal-epithelial transition process by modulating multiple EMT regulators. Combination studies using EGCG with the epigenetic modulators including the histone deacetylase (HDAC) inhibitor, trichostatin (TSA) and the DNA methyltransferase (DNMT) inhibitor such as 5-aza-2’-deoxycytidine (5- aza), revealed a synergistic effect of reactivation of CCN5 expression in highly aggressive breast cancer cells. Our findings help to assess the key mechanisms of EGCG chemoprevention and therapy by impacting epigenetic pathways toward aggressive breast tumors. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2007. doi:10.1158/1538-7445.AM2011-2007

Abstract 3712: 2-Methoxyestradiol inhibits Barrett's esophageal adenocarcinoma growth and aggressive phenotypes through differential regulation of β-catenin-E-cadherin-axis

The purpose of this study was to evaluate whether 2-methoxyestradiol (2-ME 2 ), a promising anticancer agent, modulates Barrett9s esophageal adenocarcinoma (BEAC) cell growth and behavior through cellular pathway involving beta-catenin in partnership with E-cadherin, which appears to play a critical role in the induction of antitumor responses in cancer cells. We found that 2-ME 2 markedly reduced the BEAC cell proliferation via regulating apoptotic machinery such as Bcl-2 and Bax. It may nullify the aggressive behavior of the cells by reducing the migratory behavior. Expressions of beta-catenin and E-cadherin and binding of these two proteins is activated in a 2-ME 2 -dependent fashion in Bic-1 cells. Moreover, over expressions of these two proteins may be due to the stabilization of these proteins by 2-ME 2 . We found that 2-ME 2 -induced anti-migratory effects are mediated through the beta-catenin -E-cadherin signaling pathways. In view of these results, we determined whether 2-ME 2 reduces BEAC tumor growth. Administration of 2-ME2 significantly decreased the growth of BEAC cells xenografted on the flank of nude mice. The evidence presented points out that the impact of 2-ME 2 on beta-catenin-orchestrated signal transduction plausibly plays a multi-faceted functional role to inhibit the proliferation and cell migration of 2-ME 2 treated malignant cells and it could be a potential candidate in novel treatment strategies for Barrett9s esophageal adenocarcinoma Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3712.

Abstract 5160: Tumor cells potentiate mesenchymal stem cells-pericytes transition and requirement through PDGF-BB-NRP-1 axis

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC New blood vessel formation or angiogenic switch is an essential event in the development of solid tumors and their metastatic growth. Tumor blood vessel formation and remodeling is a complex and multi-step processes. The differentiation and recruitment of mural cells including vascular smooth muscle cells and pericytes are essential steps in tumor angiogenesis. However, the role of tumor cells in differentiation and recruitment of mural cells is unknown. In this study we focus on the role of tumor cells in governing the differentiation of mesenchymal stem cells (MSCs) to pericytes and their recruitment in tumor angiogenesis process. We show that C3H/10T1/2 mouse embryonic mesenchymal stem cells, under the influence of different tumor cells-derived conditioned media, differentiate into mature pericytes. These differentiated pericytes, in turn, are recruited to bind with capillary-like networks formed by endothelial cells on the matrigel under in vitro condition. The degree of recruitment of pericytes into in vitro neo-angiogenesis is tumor cell phenotype specific. Interestingly, the invasive cells recruit less pericytes as compared to non-invasive cells. We identify tumor cell-secreted platelet derived growth factor (PDGF-BB) as a crucial factor controlling differentiation and recruitment processes through a cross-talk with NRP-1. These new insights into the roles of tumor cell-secreted PDGF in MSCs-fate determination may help in developing new antiangiogenic strategies to prevent the tumor growth and metastasis and also to treat cancers more effectively. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5160.