Dowdy, Sean C.

Abstract Purpose: Recent progress in understanding the molecular biology of epithelial ovarian cancer has not yet translated into individualized treatment for these women or improvements in their disease outcome. Gene expression has been utilized to identify distinct molecular subtypes, but there have been no reports investigating whether or not molecular subtyping is predictive of response to bevacizumab in ovarian cancer. Experimental Design: DASL gene expression arrays were performed on FFPE tissue from patients enrolled on the ICON7 trial. Patients were stratified into four TCGA molecular subtypes. Associations between molecular subtype and the efficacy of randomly assigned therapy with bevacizumab were assessed. Results: Molecular subtypes were assigned as follows: 122 immunoreactive (34%), 96 proliferative (27%), 73 differentiated (20%), and 68 mesenchymal (19%). In univariate analysis patients with tumors of proliferative subtype obtained the greatest benefit from bevacizumab with a median PFS improvement of 10.1 months [HR, 0.55 (95% CI, 0.34–0.90), P = 0.016]. For the mesenchymal subtype, bevacizumab conferred a nonsignificant improvement in PFS of 8.2 months [HR 0.78 (95% CI, 0.44–1.40), P = 0.41]. Bevacizumab conferred modest improvements in PFS for patients with immunoreactive subtype (3.8 months; P = 0.08) or differentiated subtype (3.7 months; P = 0.61). Multivariate analysis demonstrated significant PFS improvement in proliferative subtype patients only [HR, 0.45 (95% CI, 0.27–0.74), P = 0.0015]. Conclusions: Ovarian carcinoma molecular subtypes with the poorest survival (proliferative and mesenchymal) derive a comparably greater benefit from treatment that includes bevacizumab. Validation of our findings in an independent cohort could enable the use of bevacizumab for those patients most likely to benefit, thereby reducing side effects and healthcare cost. Clin Cancer Res; 23(14); 3794–801. ©2017 AACR.

Abstract Background: The strongest known risk factor for endometrial cancer is obesity. To determine whether SNPs associated with increased body mass index (BMI) or waist–hip ratio (WHR) are associated with endometrial cancer risk, independent of measured BMI, we investigated relationships between 77 BMI and 47 WHR SNPs and endometrial cancer in 6,609 cases and 37,926 country-matched controls. Methods: Logistic regression analysis and fixed effects meta-analysis were used to test for associations between endometrial cancer risk and (i) individual BMI or WHR SNPs, (ii) a combined weighted genetic risk score (wGRS) for BMI or WHR. Causality of BMI for endometrial cancer was assessed using Mendelian randomization, with BMIwGRS as instrumental variable. Results: The BMIwGRS was significantly associated with endometrial cancer risk (P = 3.4 × 10−17). Scaling the effect of the BMIwGRS on endometrial cancer risk by its effect on BMI, the endometrial cancer OR per 5 kg/m2 of genetically predicted BMI was 2.06 [95% confidence interval (CI), 1.89–2.21], larger than the observed effect of BMI on endometrial cancer risk (OR = 1.55; 95% CI, 1.44–1.68, per 5 kg/m2). The association attenuated but remained significant after adjusting for BMI (OR = 1.22; 95% CI, 1.10–1.39; P = 5.3 × 10−4). There was evidence of directional pleiotropy (P = 1.5 × 10−4). BMI SNP rs2075650 was associated with endometrial cancer at study-wide significance (P < 4.0 × 10−4), independent of BMI. Endometrial cancer was not significantly associated with individual WHR SNPs or the WHRwGRS. Conclusions: BMI, but not WHR, is causally associated with endometrial cancer risk, with evidence that some BMI-associated SNPs alter endometrial cancer risk via mechanisms other than measurable BMI. Impact: The causal association between BMI SNPs and endometrial cancer has possible implications for endometrial cancer risk modeling. Cancer Epidemiol Biomarkers Prev; 25(11); 1503–10. ©2016 AACR.

Abstract Although the majority of patients with endometrial cancer (EC) are diagnosed early when disease is confined in the uterus and prognosis is excellent, there is a subset of patients with advanced, metastatic, recurrent or persistent after surgery disease with dismal prognosis. Chemotherapy has a critical role for these patients. Carboplatin (carbo) and paclitaxel (taxol) is the standard first-line chemotherapy in EC with response rates as low as 50% and even lower for recurrent disease. Furthermore, many patients will eventually relapse with chemo-resistant disease and very poor prognosis. As the chemotherapeutic options for these patients are limited and of questionable efficacy, it is of paramount importance that novel agents are identified to increase or restore chemo-sensitization to platinum-based chemotherapy. Quinacrine (QC) is an inexpensive antimalarial drug with a predictable safety profile which recently surfaced as a promising anticancer agent thought to be associated with decreased risk of developing chemo-resistance through targeting multiple pathways simultaneously. While prior investigators have provided evidence that QC exerts strong anticancer activity against a wide range of solid tumors, there are no studies focused on QC in EC. In our study, QC exhibited strong synergism in vitro when combined with cisplatin, carbo or taxol with the highest level of synergism being observed in the most chemo-resistant EC cell line. Neither QC monotherapy (QC every other day for 3 weeks) nor standard chemotherapy (carbo+taxol for 3 cycles, on days 3, 7, 11) significantly delayed tumor growth in the mouse xenografts. Only combination (standard chemo + QC every other day during carbo+taxol treatment) and maintenance (combination regimen followed by QC every other day until end of study) significantly augmented carbo+taxol antiproliferative effect as evidenced by the significant decrease in tumor burden and delayed tumor growth in xenografts. Combination treatment was associated with a 14-day prolongation of median survival compared to carbo+taxol (68 vs. 54 days). Maintenance therapy with QC was proven superior to carbo+taxol as it resulted in long-term stabilization of disease and further prolongation of overall survival; in fact, median survival in the maintenance group was not reached as the mice were surviving at the end of study. QC alone, in combination with carbo+taxol or as maintenance was well-tolerated with no issues of weight loss compared to control mice. A yellow skin discoloration was noted during QC treatment which was entirely reversible within few days upon QC discontinuation. In conclusion, QC exhibited significant antitumor activity against EC cell lines in vitro and was successful in stabilizing disease and prolonging survival as maintenance therapy in chemo-resistant EC mouse xenografts. This data suggests that QC may be an important adjunct to standard chemotherapy for patients with recurrent EC. Citation Format: Eleftheria Kalogera, Debarshi Roy, Ashwani Khurana, Susmita Mondal, Xiaoping He, Sean C. Dowdy, Viji Shridhar. Quinacrine in endometrial cancer: repurposing an old antimalarial drug. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 261.

Epithelial stromal cells represent a major cellular component of human uterine endometrium that is subject to tight hormonal regulation. Through cell-cell contacts and/or paracrine mechanisms, stromal cells play a significant role in the malignant transformation of epithelial cells. We isolated stromal cells from normal human endometrium and investigated the morphological and transcriptional changes induced by estrogen, progesterone and tamoxifen. We demonstrated that stromal cells express appreciable levels of estrogen and progesterone receptors and undergo different morphological changes upon hormonal stimulation. Microarray analysis indicated that both estrogen and progesterone induced dramatic alterations in a variety of genes associated with cell structure, transcription, cell cycle, and signaling. However, divergent patterns of changes, and in some genes opposite effects, were observed for the two hormones. A large number of genes are identified as novel targets for hormonal regulation. These hormone-responsive genes may be involved in normal uterine function and the development of endometrial malignancies.

Abstract Edmonston vaccine strains of measles virus (MV) have significant antitumor activity in mouse xenograft models of ovarian cancer. MV engineered to express the sodium iodide symporter gene (MV-NIS) facilitates localization of viral gene expression and offers a tool for tumor radiovirotherapy. Here, we report results from a clinical evaluation of MV-NIS in patients with taxol- and platinum-resistant ovarian cancer. MV-NIS was given intraperitoneally every 4 weeks for up to 6 cycles. Treatment was well tolerated and associated with promising median overall survival in these patients with heavily pretreated ovarian cancer; no dose-limiting toxicity was observed in 16 patients treated at high-dose levels (108–109 TCID50), and their median overall survival of 26.5 months compared favorably with other contemporary series. MV receptor CD46 and nectin-4 expression was confirmed by immunohistochemistry in patient tumors. Sodium iodide symporter expression in patient tumors after treatment was confirmed in three patients by 123I uptake on SPECT/CTs and was associated with long progression-free survival. Immune monitoring posttreatment showed an increase in effector T cells recognizing the tumor antigens IGFBP2 and FRα, indicating that MV-NIS treatment triggered cellular immunity against the patients' tumor and suggesting that an immune mechanism mediating the observed antitumor effect. Our findings support further clinical evaluation of MV-NIS as an effective immunovirotherapy. Cancer Res; 75(1); 22–30. ©2014 AACR.

AbstractThe aim of the present review is to summarize the current evidence on the role of pelvic and para‐aortic lymphadenectomy in endometrial cancer. In 1988, the International Federation of Obstetrics and Gynecology recommended surgical staging for endometrial cancer patients. However, 25 years later, the role of lymph node dissection remains controversial. Although the findings of two large independent randomized trials suggested that pelvic lymphadenectomy provides only adjunctive morbidity with no clear influence on survival outcomes, the studies have many pitfalls that limit interpretation of the results. Theoretically, lymphadenectomy may help identify patients with metastatic dissemination, who may benefit from adjuvant therapy, thus reducing radiation‐related morbidity. Also, lymphadenectomy may eradicate metastatic disease. Because lymphatic spread is relatively uncommon, our main effort should be directed at identifying patients who may potentially benefit from lymph node dissection, thus reducing the rate of unnecessary treatment and associated morbidity. This review will discuss the role of lymphadenectomy in endometrial cancer, focusing on patient selection, extension of the surgical procedure, postoperative outcomes, quality of life and costs. The need for new surgical studies and efficacious systemic drugs is recommended.