J. Lefringhouse

Inhibition of the integrin/FAK signaling axis and c-Myc synergistically disrupts ovarian cancer malignancy

Integrins, a family of heterodimeric receptors for extracellular matrix, are promising therapeutic targets for ovarian cancer, particularly high-grade serous-type (HGSOC), as they drive tumor cell attachment, migration, proliferation and survival by activating focal adhesion kinase (FAK)-dependent signaling. Owing to the potential off-target effects of FAK inhibitors, disruption of the integrin signaling axis remains to be a challenge. Here, we tackled this barrier by screening for inhibitors being functionally cooperative with small-molecule VS-6063, a phase II FAK inhibitor. From this screening, JQ1, a potent inhibitor of Myc oncogenic network, emerged as the most robust collaborator. Treatment with a combination of VS-6063 and JQ1 synergistically caused an arrest of tumor cells at the G2/M phase and a decrease in the XIAP-linked cell survival. Our subsequent mechanistic analyses indicate that this functional cooperation was strongly associated with the concomitant disruption of activation or expression of FAK and c-Myc as well as their downstream signaling through the PI3K/Akt pathway. In line with these observations, we detected a strong co-amplification or upregulation at genomic or protein level for FAK and c-Myc in a large portion of primary tumors in the TCGA or a local HGSOC patient cohort. Taken together, our results suggest that the integrin–FAK signaling axis and c-Myc synergistically drive cell proliferation, survival and oncogenic potential in HGSOC. As such, our study provides key genetic, functional and signaling bases for the small-molecule-based co-targeting of these two distinct oncogenic drivers as a new line of targeted therapy against human ovarian cancer.

CD151 represses mammary gland development by maintaining the niches of progenitor cells

Tetraspanin CD151 interacts with laminin-binding integrins (i.e., α3β1, α6β1 and α6β4) and other cell surface molecules to control diverse cellular and physiological processes, ranging from cell adhesion, migration and survival to tissue architecture and homeostasis. Here, we report a novel role of CD151 in maintaining the branching morphogenesis and activity of progenitor cells during the pubertal development of mammary glands. In contrast to the disruption of laminin-binding integrins, CD151 removal in mice enhanced the tertiary branching in mammary glands by 2.4-fold and the number of terminal end buds (TEBs) by 30%, while having minimal influence on either primary or secondary ductal branching. Consistent with these morphological changes are the skewed distribution of basal/myoepithelial cells and a 3.2-fold increase in proliferating Ki67-positive cells. These novel observations suggest that CD151 impacts the branching morphogenesis of mammary glands by upregulating the activities of bipotent progenitor cells. Indeed, our subsequent analyses indicate that upon CD151 removal the proportion of CD24HiCD49fLow progenitor cells in the mammary gland increased by 34%, and their proliferating and differentiating activities were significantly upregulated. Importantly, fibronectin, a pro-branching extracellular matrix (ECM) protein deposited underlying mammary epithelial or progenitor cells, increased by >7.2-fold. Moreover, there was a concomitant increase in the expression and nuclear distribution of Slug, a transcription factor implicated in the maintenance of mammary progenitor cell activities. Taken together, our studies demonstrate that integrin-associated CD151 represses mammary branching morphogenesis by controlling progenitor cell activities, ECM integrity and transcription program.

Prospective validation of an intraoperative algorithm to guide surgical staging in early endometrial cancer

OBJECTIVES Prospectively validate an intraoperative surgical staging algorithm to stratify patients with early endometrial cancer by risk of lymph node metastasis. METHODS Subjects with endometrial cancer clinically confined to the uterus were prospectively enrolled at an academic cancer center between Jan 2012 and Jun 2015. Study participants were stratified intraoperatively into two groups based on risk of nodal involvement using cell type, tumor grade, myometrial invasion, and tumor size in accordance with an established protocol from the Mayo Clinic. Low risk (LR) subjects received extrafascial hysterectomy with bilateral salpingo-oophorectomy; high risk (HR) patients received complete surgical staging including bilateral pelvic and para-aortic lymphadenectomy. RESULTS Of the 200 subjects enrolled, 194 were eligible for analysis. The algorithm identified 132 (68%) HR and 62 (32%) LR cancers. Of the HR subjects, 126 had lymphadenectomy performed with 14 (11%) positive for nodal metastases. Five HR subjects experienced disease recurrence. Of the 62 LR cancers, two patients developed disease recurrence. Ten LR cancers were upgraded to HR on final pathology due to lesion size (6) and grade (4). None of these patients experienced disease recurrence. The algorithm demonstrated 90% sensitivity (18/20) and 36% specificity (62/174) as determined by positive lymph nodes and/or disease recurrence. CONCLUSIONS Intraoperative assessment of early endometrial cancer can be used to determine the extent of surgical staging. The studied algorithm has low specificity and modifications are necessary to better match the surgical procedure to the risk of metastatic cancer.

Probability of Fallopian Tube and Ovarian Detection with Transvaginal Ultrasonography in Normal Women

Objective: Some ovarian malignancies may originate in the fallopian tube. The feasibility of ultrasonographically visualizing the fallopian tube is presented. Methods: In total, 549 normal women participated in the fallopian tube visualization trial, while ovarian visualization was studied in 43,521. Chi-square analysis, t-tests and multivariate analysis determined significance and interactions. Results: Ovaries were observed in 82.7% while fallopian tubes were detected in 77.2% of women and 85.2% of the time when an ovary was detected. Age, BMI or parity was not significantly different when one or both fallopian tubes were visualized. Elevated BMI had slightly greater influence than age in limiting visualization of the fallopian tubes in multivariate analysis. Conclusion: Fallopian tubes can often be identified sonographically. Ovarian visualization provides the strongest indicator favoring fallopian tube detection. Thus, ultrasonographic examinations for adnexal cancer could include evaluation of fallopian tubes even in women >60 years and in women with BMI ≥25.

Survival Advantage Associated with Decrease in Stage at Detection from Stage IIIC to Stage IIIA Epithelial Ovarian Cancer

Objective. The aim of this study was to document the survival advantage of lowering stage at detection from Stage IIIC to Stage IIIA epithelial ovarian cancer. Methods. Treatment outcomes and survival were evaluated in patients with Stage IIIA and Stage IIIC epithelial ovarian cancer treated from 2000 to 2009 at the University of Kentucky Markey Cancer Center (UKMCC) and SEER institutions. Results. Cytoreduction to no visible disease (P < 0.0001) and complete response to platinum-based chemotherapy (P < 0.025) occurred more frequently in Stage IIIA than in Stage IIIC cases. Time to progression was shorter in patients with Stage IIIC ovarian cancer (17 ± 1 months) than in those with Stage II1A disease (36 ± 8 months). Five-year overall survival (OS) improved from 41% in Stage IIIC patients to 60% in Stage IIIA patients treated at UKMCC and from 37% to 56% in patients treated at SEER institutions for a survival advantage of 19% in both data sets. 53% of Stage IIIA and 14% of Stage IIIC patients had NED at last followup. Conclusions. Decreasing stage at detection from Stage IIIC to stage IIIA epithelial ovarian cancer is associated with a 5-year survival advantage of nearly 20% in patients treated by surgical tumor cytoreduction and platinum-based chemotherapy.

Metrics of the Gynecologic Oncology Literature Focused on Cited Utilization and Costs

OBJECTIVE The newest findings on literature utilization relevant to gynecologic oncology were published by Thomson Reuters during June 2013 as determinants of journal standing. Our objective was to assess the different metrics reported for relative impact and cost for journals relevant to gynecologic oncology. METHODS 55 journals were evaluated for Impact Factor (IF), 5 Year IF, Immediacy Index, Cited Half Life, Eigenfactor (EF) Score, Article Influence (AI) scores and subscription costs obtained from publisher information. RESULTS CA-A Cancer Journal for Clinicians had the highest IF (101.78) & AI (24.502). The top EF cancer-specific journals were the Journal of Clinical Oncology, Cancer Research, Clinical Cancer Research and Oncogene. Rankings for Gynecologic Oncology (409 articles, 18,243 citations) were IF = 3.929, 43/55, EF = 0.038, 28/55, and AI = 1.099, 44/55, all higher than the previous year. The IF improved from the 5 year IF in 31 journals, including Gynecologic Oncology, 29/31. Subscription costs for Gynecologic Oncology compared favorably to other journals. CONCLUSIONS The high utilization of review information in CA-A Cancer Journal for Clinicians and Nature Review Cancer illustrated by the IF coupled with a relatively low number of articles and short cited half life indicates that they serve as a leading source of quoted cancer statistics (CA-A Cancer Journal for Clinicians). Rankings for Gynecologic Oncology and the International Journal of Gynecologic Cancer have improved. Regardless of specialty size, the Impact Factor for Gynecologic Oncology is respectably strong. The decreased IF in 44% of the journals may reflect the international economys effect on cancer research.