Katherine Fuh

AXL Is an Essential Factor and Therapeutic Target for Metastatic Ovarian Cancer

The receptor tyrosine kinase AXL is thought to play a role in metastasis; however, the therapeutic efficacy of an AXL-targeting agent remains largely untested in metastatic disease. In this study, we defined AXL as a therapeutic target for metastatic ovarian cancer. AXL is primarily expressed in metastases and advanced-stage human ovarian tumors but not in normal ovarian epithelium. Genetic inhibition of AXL in human metastatic ovarian tumor cells is sufficient to prevent the initiation of metastatic disease in vivo. Mechanistically, inhibition of AXL signaling in animals with metastatic disease results in decreased invasion and matrix metalloproteinase activity. Most importantly, soluble human AXL receptors that imposed a specific blockade of the GAS6/AXL pathway had a profound inhibitory effect on progression of established metastatic ovarian cancer without normal tissue toxicity. These results offer the first genetic validation of GAS6/AXL targeting as an effective strategy for inhibition of metastatic tumor progression in vivo. Furthermore, this study defines the soluble AXL receptor as a therapeutic candidate agent for treatment of metastatic ovarian cancer, for which current therapies are ineffective.

Direct regulation of GAS6/AXL signaling by HIF promotes renal metastasis through SRC and MET

Significance Here we report a fundamental and previously unknown role for the receptor tyrosine kinase AXL as a direct hypoxia-inducible transcription factor target driving the aggressive phenotype in renal clear cell carcinoma through the regulation of the SRC proto-oncogene nonreceptor tyrosine kinase and the MET proto-oncogene receptor tyrosine kinase. Of therapeutic relevance, we demonstrate that inactivation of growth arrest-specific 6 (GAS6)/AXL signaling using a soluble AXL decoy receptor reversed the invasive and metastatic phenotype of clear cell renal cell carcinoma (ccRCC) cells. Furthermore, we define a pathway by which GAS6/AXL signaling utilizes lateral activation of MET through SRC to maximize cellular invasion. Our data provide an alternative model for SRC and MET activation by GAS6 in ccRCC and identify AXL as a therapeutic target driving the aggressive phenotype in renal clear cell carcinoma. Dysregulation of the von Hippel–Lindau/hypoxia-inducible transcription factor (HIF) signaling pathway promotes clear cell renal cell carcinoma (ccRCC) progression and metastasis. The protein kinase GAS6/AXL signaling pathway has recently been implicated as an essential mediator of metastasis and receptor tyrosine kinase crosstalk in cancer. Here we establish a molecular link between HIF stabilization and induction of AXL receptor expression in metastatic ccRCC. We found that HIF-1 and HIF-2 directly activate the expression of AXL by binding to the hypoxia-response element in the AXL proximal promoter. Importantly, genetic and therapeutic inactivation of AXL signaling in metastatic ccRCC cells reversed the invasive and metastatic phenotype in vivo. Furthermore, we define a pathway by which GAS6/AXL signaling uses lateral activation of the met proto-oncogene (MET) through SRC proto-oncogene nonreceptor tyrosine kinase to maximize cellular invasion. Clinically, AXL expression in primary tumors of ccRCC patients correlates with aggressive tumor behavior and patient lethality. These findings provide an alternative model for SRC and MET activation by growth arrest-specific 6 in ccRCC and identify AXL as a therapeutic target driving the aggressive phenotype in renal clear cell carcinoma.

Utilization of and charges for robotic versus laparoscopic versus open surgery for endometrial cancer.

To analyze the utilization and hospital charges associated with robotic (RS) versus laparoscopic (LS) versus open surgery (OS) in endometrial cancer patients.

Survival differences of Asian and Caucasian epithelial ovarian cancer patients in the United States

OBJECTIVE To compare the racial differences in treatment and survival of Asian-Americans and White patients with epithelial ovarian cancer. METHODS Data were obtained from the Surveillance, Epidemiology, and End Results Program between 1988 and 2009 and analyzed using Chi-squared tests, Kaplan-Meier methods, and Cox regression analysis. RESULTS Of the 52,260 women, 3932 (7.5%) were coded as Asian, and 48,328 (92.5%) were White. The median age of Asians at diagnosis was 56 vs. 64 years for the Whites (p<0.001). Asians were more likely to undergo primary surgery, have an earlier stage of disease, have a diagnosis of a non-serous histology, and have lower grade tumors. The 5-year disease-specific survival (DSS) of Asians was higher compared to Whites (59.1% vs. 47.3%, p<0.001). On a subset analysis, Vietnamese, Filipino, Chinese, Korean, Japanese, and Asian Indian/Pakistani ethnicities had 5-year DSS of 62.1%, 61.5%, 61.0%, 59.0%, 54.6%, and 48.2%, respectively (p=0.015). On multivariate analysis, age at diagnosis, year of diagnosis, race, surgery, stage, and tumor grade were all independent prognostic factors for survival. Asians were further stratified to U.S. born versus those who were born in Asia and immigrated. Asian immigrants presented at a younger age compared to U.S. born Asians. Immigrants were found to have an improved 5-year DSS when compared to U.S. born Asians and Whites of 55%, 52%, and 48%, respectively (p<0.001). CONCLUSION Asians were more likely to be younger, undergo primary surgery, have an earlier stage of disease, non-serous histology, lower grade tumors, and higher survival.

Current Management of Vulvar Cancer

1. Vulvar cancer is surgically staged. 2. Imaging such as CT of the abdomen and pelvis should be performed for women with tumors 2 cm or larger or to detect lymph node or other metastases. 3. Staging should include evaluation of factors related to prognosis: tumor size, depth of invasion, lymph node involvement, and presence of distant metastases. 4. Inguinofemoral lymph node metastasis is the most important predictor of overall prognosis. 5. Inguinofemoral lymphadenectomy or sentinel lymph node evaluation can be omitted for lesions 2 cm or smaller and depth of invasion less than 1 mm. 6. Sentinel node biopsy seems to be a reliable means to pathologically assess inguinofemoral lymph node metastasis. 7. All tumors larger than 2 cm require pathologic inguinofemoral lymph node evaluation. 8. Radical local excision or modified radical vulvectomy is appropriate for most stage I and II lesions located on the lateral or posterior aspects of the vulva. 9. A tumor-free surgical margin of at least 1 cm decreases the risk of local recurrence. 10. Chemoradiation therapy is the preferred approach for most patients with very advanced vulvar cancer.

Daily compared with 8-hour gentamicin for the treatment of intrapartum chorioamnionitis: A randomized controlled trial

OBJECTIVE: To assess whether daily gentamicin is as effective as 8-hour gentamicin for the treatment of intrapartum chorioamnionitis. METHODS: Women with a clinical diagnosis of chorioamnionitis between 32 and 42 weeks of gestation were randomly assigned in labor to receive either daily gentamicin (5 mg/kg intravenously (IV), then 2 placebo doses IV after 8 and 16 hours) or 8-hour gentamicin (2 mg/kg IV, then 1.5 mg/kg IV after 8 and 16 hours). Both groups received ampicillin (2 grams IV every 6 hours for a total of four doses). Patients who underwent cesarean delivery also received clindamycin (900 mg IV every 8 hours, for a total of three doses). The primary outcome was treatment success, defined by resolution of chorioamnionitis after 16 hours of treatment without development of endometritis. One hundred twenty-six patients were required to have 95% confidence that daily gentamicin is at worst 15% inferior to 8-hour dosing with an alpha of .05 and a beta of 0.2. RESULTS: One hundred twenty-six women were enrolled, of whom 63 received daily gentamicin and 63 received 8-hour gentamicin. One patient was excluded from data analysis. Baseline maternal and obstetric characteristics were similar between groups except for longer mean duration of ruptured membranes in the 8-hour group (679±514 compared with 469±319 minutes; P =.03). Treatment success was equal between groups (94% daily gentamicin compared with 89% 8-hour gentamicin, P =.53). There were no differences in maternal or neonatal morbidities, including neonatal sepsis and newborn hearing screen. CONCLUSION: Daily and 8-hour gentamicin appear equally effective for the treatment of intrapartum chorioamnionitis. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00185991. LEVEL OF EVIDENCE: I

AXL modulates extracellular matrix protein expression and is essential for invasion and metastasis in endometrial cancer

The receptor tyrosine kinase AXL promotes migration, invasion, and metastasis. Here, we evaluated the role of AXL in endometrial cancer. High immunohistochemical expression of AXL was found in 76% (63/83) of advanced-stage, and 77% (82/107) of high-grade specimens and correlated with worse survival in uterine serous cancer patients. In vitro, genetic silencing of AXL inhibited migration and invasion but had no effect on proliferation of ARK1 endometrial cancer cells. AXL-deficient cells showed significantly decreased expression of phospho-AKT as well as uPA, MMP-1, MMP-2, MMP-3, and MMP-9. In a xenograft model of human uterine serous carcinoma with AXL-deficient ARK1 cells, there was significantly less tumor burden than xenografts with control ARK1 cells. Together, these findings underscore the therapeutic potentials of AXL as a candidate target for treatment of metastatic endometrial cancer.

Comparison of bevacizumab alone or with chemotherapy in recurrent ovarian cancer patients

BACKGROUND To compare the efficacy of chemotherapy (C) combined with bevacizumab (Bev) versus Bev alone in recurrent, heavily pretreated epithelial ovarian cancer (EOC). METHODS A multicenter analysis of patients treated from 2004 to 2011 was performed. Demographic, treatment, response, and adverse event information were obtained. Progression-free (PFS) and overall survival (OS) were analyzed. RESULTS Of 277 patients (median age: 58years), the majority had Stage III and IV (86%) disease, and 72% had serous histology. 244 (88%) were treated with C+Bev and 33 (12%) with Bev. Corresponding median progression-free survival (PFS) was 8.7 and 6.7months, and median overall survival (OS) was 14.3 and 10.5months, respectively. The chemotherapeutic agents combined with Bev and the median OS include: pegylated liposomal doxorubicin (n=19, OS of 20.4months), taxanes (n=55, OS of 20.2months), gemcitabine (n=106, OS of 14.1months), topotecan (n=43, OS of 13months), and cyclophosphamide (n=21, OS of 13months). There was no significant difference in toxicities between the C+Bev vs. Bev alone group. CONCLUSION This retrospective analysis supports that combination chemotherapy and bevacizumab prolongs PFS and OS compared with bevacizumab alone.

Gynecologic Oncologists’ Perceptions of Palliative Care and Associated Barriers: A Survey of the Society of Gynecologic Oncology

Objectives: Gynecologic oncologists frequently care for patients at the end of life with the aid of palliative care (PC) specialists. Our primary objectives were to identify perceived barriers to integrating specialty PC into gynecologic cancer care. Materials and Methods: Members of the Society of Gynecologic Oncology (SGO) were invited to participate in an anonymous online survey. A Likert scale captured perceptions regarding primary and specialty PC, frequent barriers to use of PC, and potential interventions. Results: A total of 174 (16%) gynecologic oncologists completed the survey. The majority (75%) agreed or strongly agreed that PC should be integrated into cancer care at diagnosis of advanced or metastatic cancer. The most frequently perceived PC barriers included patients’ unrealistic expectations (54%), limited access to specialty PC (25%), poor reimbursement (25%), time constraints (22%), and concern of reducing hope or trust (21%). The most agreed upon potential intervention was increased access to outpatient PC (80%). Conclusions: According to this cohort of SGO members, families’ or patients’ unrealistic expectations are the most frequent barriers to specialty PC. Understanding this communication breakdown is critically important.

Radiation Therapy for Recurrent Clear-Cell Cancer of the Ovary.

Objective Given the relative chemo-resistant nature of clear-cell gynecologic cancers, we investigated the utility of radiation therapy (RT) to treat recurrent clear-cell carcinoma (CCC) of the ovary. Methods A retrospective chart review of patients with recurrent CCC managed from 1994–2012 was conducted at 2 academic medical centers. Demographic and clinicopathologic factors were abstracted and evaluated using Pearson χ2 or t tests, Kaplan-Meier and Cox regression analyses. Results Fifty-three patients had recurrent CCC, and 24 (45.3%) of these patients received RT. There were no significant differences in age, stage, optimal cytoreduction, platinum response, or the percentage of patients that received more than 3 regimens of chemotherapy between the 2 groups. Patients who received RT for recurrent CCC were more likely to have had a focal recurrence (62.5% vs 10.3%, P ≤ 0.001) and to have undergone secondary cytoreduction (70.8% vs 10.3%, P ≤ 0.001). Of patients who received RT, 73.9% underwent surgery with or before their treatment. Five-year survival after recurrence was significantly higher in the group that received RT, 62.9% versus 18.8% (P = 0.002). In a multivariate analysis, platinum-sensitive disease and RT were associated with improved survival from recurrence, (hazard ratio, 0.26; 95% confidence interval, 0.08-0.81; P = 0.02 and hazard ratio, 0.28; 95% confidence interval, 0.09–0.90, P = 0.03, respectively). Conclusions In this cohort of patients with recurrent CCC, platinum-sensitive disease and RT are associated with improved survival. However, it is important to note that the majority of these patients underwent surgery along with RT, and it may be that the benefit of RT is limited to those who undergo secondary cytoreduction.