[Providing Opportunities for Close Examination of Lynch Syndrome after Microsatellite Instability Testing in a Hospital Setting].

Microsatellite instability(MSI)testing is performed in cancer patients to determine the indication for chemotherapy with immune checkpoint inhibitors. We report on our scheme to ensure that Lynch syndrome patients are offered the opportunity for genetic counseling and genetic testing. Two hundred and eight cancer patients(107 males and 101 females, 20- 87 years, mean 63.3 years)underwent MSI testing at our hospital between February 2019 and November 2021. From February 2019 to December 2020, the MSI testing was performed with a consent document that included a commentary on Lynch syndrome, and the results were explained only by the attending cancer doctors. Eleven(8.6%)of the 136 cases had MSI-high, but none of them led to a visit to the genetic medicine department. The Genome Center in our hospital, which was operational from April 2020, undertook information sharing by multiple professions and established a system to provide appropriate support to cancer doctors. Consecutively, 72 MSI tests were performed between January and November 2021, and 2 patients(2.8%)with MSI-high(1 with endometrial cancer and 1 with colorectal cancer)were referred to the Department of Clinical Genetics for genetic counseling. Through genetic testing, both were diagnosed with Lynch syndrome, and information on future surveillance and health care for blood relatives was provided.

Significance of Lymphovascular Space Invasion by the Sarcomatous Component in Uterine Carcinosarcoma.

OBJECTIVE: The aim of this study was to examine the significance of lymphovascular space invasion (LVSI) with a sarcomatous component on the tumor characteristics and clinical outcomes of women with uterine carcinosarcoma (UCS). METHODS: This was a secondary analysis of a prior multicenter retrospective study that examined women with stage I-IV UCS who underwent primary hysterectomy. Archived histopathology slides were reviewed and LVSI was scored as follows: LVSI with a carcinomatous component alone (LVSI-carcinoma; n = 375, 76.8%) or LVSI containing a sarcomatous component with or without a carcinomatous component (LVSI-sarcoma; n = 113, 23.2%). Qualitative metrics of LVSI were correlated to clinicopathological factors and survival outcome. RESULTS: Tumors in the LVSI-sarcoma group were more likely to have sarcoma dominance (82.1 vs. 26.4%) heterologous sarcomatous component (51.3 vs. 37.9%), low-grade carcinoma (42.5 vs. 22.4%), and large tumor size (81.0 vs. 70.2%) in the primary tumor site compared with tumors in the LVSI-carcinoma group (all p < 0.05). On multivariate analysis, LVSI-sarcoma was independently associated with decreased progression-free survival (5-year rates: 34.9 vs. 40.8%, adjusted hazard ratio [HR] 1.84, 95% confidence interval [CI] 1.36-2.50, p < 0.001), and cause-specific survival (5-year rates: 41.8 vs. 55.9%, adjusted HR 1.95, 95% CI 1.39-2.75, p < 0.001) compared with LVSI-carcinoma. Postoperative radiotherapy for women with LVSI-sarcoma had a higher reduction rate of recurrence/progression of disease (54% reduction, p = 0.04) compared with postoperative radiotherapy for women with LVSI-carcinoma (26% reduction, p = 0.08). CONCLUSION: In UCS, the presence of a sarcomatous component in LVSI is particularly prevalent when a tumor has sarcoma dominance. Our study suggests that LVSI containing a sarcomatous component may be a predictor of decreased survival for women with UCS.

Proposal for a Risk-Based Categorization of Uterine Carcinosarcoma.

PURPOSE: To propose a categorization model of uterine carcinosarcoma (UCS) based on tumor cell types (carcinoma and sarcoma) and sarcoma dominance. METHODS: This secondary analysis of a prior multicenter retrospective study examined 889 cases of UCS with available histologic evaluation. Based on survival outcome, cases were clustered into three groups: low-grade carcinoma with nondominant homologous sarcoma [type A, n = 96 (10.8%)], (1) low-grade carcinoma with heterologous sarcoma or any sarcoma dominance and (2) high-grade carcinoma with nondominant homologous sarcoma [type B, n = 412 (46.3%)], and high-grade carcinoma with heterologous sarcoma or any sarcoma dominance [type C, n = 381 (42.9%)]. Tumor characteristics and outcome were examined based on the categorization. RESULTS: Women in type C category were more likely to be older, obese, and Caucasian, whereas those in type A category were younger, less obese, Asian, and nulligravid (all P < 0.01). Type C tumors were more likely to have metastatic implants, large tumor size, lymphovascular space invasion with sarcoma cells, and higher lymph node ratio, whereas type A tumors were more likely to be early-stage disease and small (all P < 0.05). On multivariate analysis, tumor categorization was independently associated with progression-free survival (5-year rates: 70.1% for type A, 48.3% for type B, and 35.9% for type C, adjusted P < 0.01) and cause-specific survival (5-year rates: 82.8% for type A, 63.0% for type B, and 47.1% for type C, adjusted P < 0.01). CONCLUSION: Characteristic differences in clinicopathological factors and outcomes in UCS imply that different underlying etiologies and biological behaviors may be present, supporting a new classification system.

Significance of venous thromboembolism in women with uterine carcinosarcoma.

OBJECTIVE: To identify risk factors for venous thromboembolism (VTE) and to examine the association of VTE and survival in women with uterine carcinosarcoma. METHODS: This multicenter retrospective study examined 906 women who underwent primary surgical treatment for stage I-IV uterine carcinosarcoma. Time-dependent analyses were performed for cumulative incidence of VTE after surgery on multivariate models. RESULTS: There were 72 (7.9%) women who developed VTE after surgery with 1-, 2-, and 5-year cumulative incidences being 5.1%, 7.3%, and 10.2%, respectively. On multivariate analysis, older age (hazard ratio [HR] per year 1.03, P=0.012), non-Asian race (HR 6.28, P<0.001), large body habitus (HR per kg/m2 1.04, P=0.014), residual disease at surgery (HR 3.04, P=0.003), tumor size ≥5cm (HR 2.73, P=0.003), and stage IV disease (HR 2.12, P=0.025) were independently associated with increased risk of developing VTE. A risk pattern analysis identified that obese Non-Asian women with large tumors (13.7% of population) had the highest incidence of VTE (2-year cumulative rate, 26.1%) whereas Asian women with no residual disease (47.1% of population) had the lowest (2-year cumulative rate, 1.6%) (P<0.001). Presence of carcinoma/sarcoma in metastatic sites was significantly associated with increased risk of VTE compared to carcinoma alone (2-year rates, 31.2% versus 8.4%, P=0.049). VTE was independently associated with decreased progression-free survival on multivariate models (5-year rates, 24.9% versus 47.2%, HR 1.46, 95%CI 1.05-2.04, P=0.026). CONCLUSION: Our study suggests that VTE represents a surrogate marker of aggressive tumor behavior and diminished patient condition in uterine carcinosarcoma; obese Non-Asian women with large tumors carry a disproportionally high risk of VTE, suggesting that long-term prophylaxis may benefit this population.

Survival outcome of women with stage IV uterine carcinosarcoma who received neoadjuvant chemotherapy followed by surgery.

BACKGROUND AND OBJECTIVES: To examine survival of women with stage IV uterine carcinosarcoma (UCS) who received neoadjuvant chemotherapy followed by hysterectomy. METHODS: This is a nested case-control study within a retrospective cohort of 1192 UCS cases. Women who received neoadjuvant chemotherapy followed by hysterectomy based-surgery for stage IV UCS (n = 26) were compared to those who had primary hysterectomy-based surgery without neoadjuvant chemotherapy for stage IV UCS (n = 120). Progression-free survival (PFS) and cause-specific survival (CSS) were examined. RESULTS: The most common regimen for neoadjuvant chemotherapy was carboplatin/paclitaxel (53.8%). Median number of neoadjuvant chemotherapy cycles was 4. PFS was similar between the neoadjuvant chemotherapy group and the primary surgery group (unadjusted-hazard ratio [HR] 1.19, 95% confidence interval [CI] 0.75-1.89, P = 0.45). Similarly, CSS was comparable between the two groups (unadjusted-HR 1.13, 95%CI 0.68-1.90, P = 0.64). When the types of neoadjuvant chemotherapy regimens were compared, women who received a carboplatin/paclitaxel regimen had better survival outcomes compared to those who received other regimens: PFS, unadjusted-HR 0.38, 95%CI 0.15-0.93, P = 0.027; and CSS, unadjusted-HR 0.21, 95%CI 0.07-0.61, P = 0.002. CONCLUSION: Our study found that there is no statistically significant difference in survival between women with stage IV UCS who are tolerated neoadjuvant chemotherapy and those who undergo primary surgery.

Impact of adjuvant therapy on recurrence patterns in stage I uterine carcinosarcoma.

BACKGROUND: To examine recurrence patterns in women with stage I uterine carcinosarcoma (UCS) stratified by adjuvant therapy pattern. METHODS: We examined 443 cases of stage I UCS derived from a retrospective cohort of 1192 UCS cases from 26 institutions. Adjuvant therapy patterns after primary hysterectomy-based surgery were correlated to recurrence patterns. RESULTS: The most common adjuvant therapy was chemotherapy alone (41.5%) followed by chemotherapy/radiotherapy (15.8%) and radiotherapy alone (8.4%). Distant-recurrence was the most common recurrence pattern (5-year cumulative rate, 28.1%) followed by local-recurrence (13.3%). On multivariate analysis, chemotherapy but not radiotherapy remained an independent prognostic factor for decreased risk of local-recurrence (5-year cumulative rates 8.7% versus 19.8%, adjusted-hazard ratio [HR] 0.46, 95% confidence interval [CI] 0.25-0.83, P=0.01) and distant-recurrence (21.2% versus 38.0%, adjusted-HR 0.41, 95%CI 0.27-0.62, P<0.001). The chemotherapy/radiotherapy group had a lower 5-year cumulative local-recurrence rate compared to the chemotherapy alone group but it did not reach statistical significance (5.1% versus 10.1%, adjusted-HR 0.46, 95%CI 0.13-1.58, P=0.22). Radiotherapy significantly decreased local-recurrence when tumors had high-grade carcinoma, sarcoma component dominance, and deep myometrial tumor invasion (all, P<0.05); and combining radiotherapy with chemotherapy was significantly associated with decreased local-recurrence compared to chemotherapy alone in the presence of multiple risk factors (5-year cumulative rates, 2.5% versus 21.8%, HR 0.12, 95%CI 0.02-0.90; P=0.013) but not in none/single factor (P=0.36). CONCLUSION: Adjuvant chemotherapy appears to be effective to control both local- and distant-recurrences in stage I UCS; adding radiotherapy to chemotherapy may be effective to control local-recurrence when the tumor exhibits multiple risk factors.

Salvage chemotherapy with taxane and platinum for women with recurrent uterine carcinosarcoma.

OBJECTIVE: To examine survival after recurrence (SAR) among women with recurrent uterine carcinosarcoma who received a taxane/platinum doublet as the first-line salvage chemotherapy. METHODS: We retrospectively examined 148 women with recurrent uterine carcinosarcoma who received salvage chemotherapy within a cohort of 906 uterine carcinosarcomas. An independent association of salvage chemotherapy type and SAR was examined with multivariate analysis. RESULTS: There were 71 (48.0%) women who received a taxane/platinum regimen. On univariate analysis, women who received a taxane/platinum doublet had a higher 2-year SAR rate compared to women who received non-taxane/platinum regimens (55.5% versus 34.8%, P<0.001). On multivariate analysis, use of taxane/platinum regimen was independently associated with improved SAR compared to the non-taxane/platinum regimens (adjusted-hazard ratio [HR] 0.56, 95% confidence interval [CI] 0.35 to 0.91, P=0.02). When stratified by disease-free interval, women with a disease-free interval ≥6months who received a taxane/platinum doublet had a higher 2-year SAR rate compared to those who received non-taxane/platinum regimens (61.9% versus 40.0%, HR 0.46, 95% CI 0.28 to 0.75, P=0.002); conversely, in women with a disease-free interval <6months, 2-year SAR rates were similar between the two groups (20.5% versus 18.4%, HR 0.80, 95% CI 0.33 to 1.90, P=0.61). Among women who received a taxane/platinum doublet as adjuvant chemotherapy, re-treatment with taxane/platinum doublet as salvage chemotherapy remained beneficial (2-year SAR rate, 62.1% versus 39.7%, HR 0.40, 95% CI 0.18 to 0.86, P=0.019). CONCLUSION: Our study suggests that taxane/platinum doublet may be a more effective chemotherapy regimen compared to other regimens among women with recurrent uterine carcinosarcoma, especially for those who had a disease-free interval of ≥6months.

Tumor characteristics and survival outcomes of women with tamoxifen-related uterine carcinosarcoma.

OBJECTIVE: To examine tumor characteristics and survival outcome of women with uterine carcinosarcoma who had a history of tamoxifen use. METHODS: This is a multicenter retrospective study examining stage I-IV uterine carcinosarcoma cases based on history of tamoxifen use. Patient demographics, tumor characteristics, treatment pattern, and survival outcomes were compared between tamoxifen users and non-users. RESULTS: Sixty-six cases of tamoxifen-related uterine carcinosarcoma were compared to 1009 cases with no history of tamoxifen use. Tamoxifen users were more likely to be older (mean age, 69 versus 64, P<0.001) and had a past history of malignancy (100% versus 12.7%, P<0.001). Tamoxifen-related uterine carcinosarcoma was significantly associated with a higher proportion of stage IA disease (48.4% versus 29.9%) and a lower risk of stage IVB disease (7.8% versus 16.0%) compared to tamoxifen-unrelated carcinosarcoma (P=0.034). Deep myometrial tumor invasion was less common in uterine carcinosarcoma related to tamoxifen use (28.3% versus 48.8%, P=0.002). On univariate analysis, tamoxifen use was not associated with progression-free survival (5-year rates 44.5% versus 46.8%, P=0.48) and disease-specific survival (64.0% versus 59.1%, P=0.39). After adjusting for age, past history of malignancy, stage, residual disease status at surgery, and postoperative treatment patterns, tamoxifen use was not associated with progression-free survival (adjusted-hazard ratio 0.86, 95% confidence interval 0.50 to 1.50, P=0.60) and disease-specific survival (adjusted-hazard ratio 0.68, 95% confidence interval 0.36 to 1.29, P=0.24). CONCLUSION: Our study suggests that tamoxifen-related uterine carcinosarcoma may have favorable tumor characteristics but have comparable stage-specific survival outcomes compared to tamoxifen-unrelated uterine carcinosarcoma.

Survival outcome of stage I ovarian clear cell carcinoma with lympho-vascular space invasion.

BACKGROUND: The clinical impact of lympho-vascular space invasion (LVSI) in early-stage ovarian clear cell carcinoma (OCCC) is not well understood. Given the distinct tumor biology and survival patterns of OCCC, the significance of LVSI on survival outcome and treatment response was examined in OCCC. METHODS: A multicenter study was conducted to examine stage IA-IC3 OCCC cases that underwent primary surgical staging including lymphadenectomy. LVSI status was determined from archived histopathology slides, correlated with clinico-pathological results, chemotherapy patterns, and survival outcomes. RESULTS: LVSI was observed in 47 (20.3%) among 232 cases. In univariate analysis, LVSI was associated with older age (p=0.042), large tumor size (p=0.048), and stage IC (p=0.035). In survival analysis, LVSI was associated with decreased disease-free survival (DFS, 5-year rate, 70.6% versus 92.1%, p=0.0004) and overall survival (OS, 78.8% versus 93.3%, p=0.008) on univariate analysis. After controlling for age, tumor size, stage, and chemotherapy use, LVSI remained an independent prognostic factor for decreased survival outcomes (DFS, hazard ratio [HR] 4.35, 95% confidence interval [CI] 1.73-10.9, p=0.002; and OS, HR 4.73, 95%CI 1.60-14.0, p=0.015). Among 210 cases who received postoperative chemotherapy, while regimen type did not impact survival outcome regardless of LVSI status (DFS, p=0.63), the number of administered cycles showed a survival benefit towards ≥6cycles for patients with LVSI-positive tumors (DFS, p=0.009; and OS, p=0.016). CONCLUSION: LVSI is an important marker to predict survival outcome of stage I OCCC. Regardless of chemotherapy type, patients with stage I OCCC showing LVSI may benefit from receiving postoperative chemotherapy.

Annexin A4-conferred platinum resistance is mediated by the copper transporter ATP7A.

Although platinum drugs are often used for the chemotherapy of human cancers, platinum resistance is a major issue and may preclude their use in some cases. We recently reported that enhanced expression of Annexin A4 (Anx A4) increases chemoresistance to carboplatin through increased extracellular efflux of the drug. However, the precise mechanisms underlying that chemoresistance and the relationship of Anx A4 to platinum resistance in vivo remain unclear. In this report, the in vitro mechanism of platinum resistance induced by Anx A4 was investigated in endometrial carcinoma cells (HEC1 cells) with low expression of Anx A4. Forced expression of Anx A4 in HEC1 cells resulted in chemoresistance to platinum drugs. In addition, HEC1 control cells were compared with Anx A4-overexpressing HEC1 cells in xenografted mice. Significantly greater chemoresistance to cisplatin was observed in vivo in Anx A4-overexpressing xenografted mice. Immunofluorescence analysis revealed that exposure to platinum drugs induced relocation of Anx A4 from the cytoplasm to the cellular membrane, where it became colocalized with ATP7A, a copper transporter also well known as a mechanism of platinum efflux. ATP7A expression suppressed by small interfering RNA had no effect on HEC1 control cells in terms of chemosensitivity to platinum drugs. However, suppression of ATP7A in Anx A4-overexpressing platinum-resistant cells improved chemosensitivity to platinum drugs (but not to 5-fluorouracil) to a level comparable to that of control cells. These results indicate that enhanced expression of Anx A4 confers platinum resistance by promoting efflux of platinum drugs via ATP7A.

Plasma membrane proteomics identifies bone marrow stromal antigen 2 as a potential therapeutic target in endometrial cancer.

This report utilizes a novel proteomic method for discovering potential therapeutic targets in endometrial cancer. We used a biotinylation-based approach for cell-surface protein enrichment combined with isobaric tags for relative and absolute quantitation (iTRAQ) technology using nano liquid chromatography-tandem mass spectrometry analysis to identify specifically overexpressed proteins in endometrial cancer cells compared with normal endometrial cells. We identified a total of 272 proteins, including 11 plasma membrane proteins, whose expression increased more than twofold in at least four of seven endometrial cancer cell lines compared with a normal endometrial cell line. Overexpression of bone marrow stromal antigen 2 (BST2) was detected and the observation was supported by immunohistochemical analysis using clinical samples. The expression of BST2 was more characteristic of 118 endometrial cancer tissues compared with 59 normal endometrial tissues (p < 0.0001). The therapeutic effect of an anti-BST2 antibody was studied both in vitro and in vivo. An anti-BST2 monoclonal antibody showed in vitro cytotoxicity in BST2-positive endometrial cancer cells via antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. In an in vivo xenograft model, anti-BST2 antibody treatment significantly inhibited tumor growth of BST2-positive endometrial cancer cells in an NK cell-dependent manner. The anti-BST2 antibody had a potent antitumor effect against endometrial cancer both in vitro and in vivo, indicating a strong potential for clinical use of anti-BST2 antibody for endometrial cancer treatment. The combination of biotinylation-based enrichment of cell-surface proteins and iTRAQ analysis should be a useful screening method for future discovery of potential therapeutic targets.

Prediction, based on resection margins, of long-term outcome of cervical intraepithelial neoplasia 3 treated by Shimodaira-Taniguchi conization.

PURPOSE: The aim of the present study was to analyze the long-term outcome of cervical intraepithelial neoplasia 3 (CIN 3) after treatment with the Shimodaira-Taniguchi conization procedure, based on the status of the resection margins. METHODS: In the Osaka University Hospital, conization using the Shimodaira-Taniguchi procedure has been routinely performed for CIN 3. Medical records of patients during the period from 2001 to 2008, whose post-conization diagnosis was CIN 3, were retrospectively analyzed for outcome versus margin status. RESULTS: During the median follow-up period of 565 days (range 34-3,013), CIN disease was again detected in 14 of 243 patients; it was found in 7 patients among 198 margin-negative cases, and in 7 patients among 45 margin-positive cases. There was a significant difference in the reappearance rate demonstrated between the cases with positive and negative margins (p = 0.0018). Among the patients whose first follow-up post-conization cytology was normal, recurrence-free probability was significantly higher in margin-negative cases than in margin-positive ones (hazard ratio, 5.19; 95% CI, 1.175-22.994; p = 0.0041). CONCLUSION: For the first time, we demonstrate that after treatment of CIN 3 lesions by Shimodaira-Taniguchi conization the status of the resection margin was a significant predictor for long-term outcome.

Recurrent endometrial carcinoma: prognosis for patients with recurrence within 6 to 12 months is worse relative to those relapsing at 12 months or later.

OBJECTIVE: We evaluated association of prognosis of endometrial carcinoma patients and treatment-free intervals (TFIs). STUDY DESIGN: We compared the effectiveness of second-line chemotherapy performed for patients with TFIs of 6-12 months and 12 or more months following a first-line chemotherapy based on taxane (paclitaxel) and carboplatin, with or without the anthracycline (TC). RESULTS: Progression-free and overall survivals were significantly shorter in patients with TFIs of 6-12 months than those with TFIs of 12 or more months. Among the patients who received similar second-line chemotherapy, response rates of 15 patients with TFIs of 12 or more months and 7 patients with TFIs of 6-12 months were 67% and 43%, respectively. Progression-free survival was significantly worse in those with TFIs of 6-12 months (median, 7 months) than those with TFIs of 12 or more months (median, 12 months). CONCLUSION: Our small retrospective analysis suggests that recurrent endometrial carcinomas with TFIs of 6-12 months can be regarded as being partially sensitive to TC-based chemotherapy.

Endometrial carcinoma: better prognosis for asymptomatic recurrences than for symptomatic cases found by routine follow-up.

BACKGROUND: The aim of this study was to determine if there is a prognostic value for the presence of symptoms at the time of recurrence detection in surgically resected endometrial carcinoma patients. METHODS: During the study period of 2000-2006, complete surgical removal of endometrial carcinoma was achieved in 271 stage I-IV endometrial cancer cases at the Department of Obstetrics and Gynecology of Osaka University Hospital, Osaka, Japan. A subsequent recurrence was detected in 29 (11%) of these cases. Patient characteristics and clinicopathological features were retrospectively reviewed utilizing their clinical records. RESULTS: Among the 29 cases with a recurrence, 13 (45%) had symptoms, whereas in the other 16 cases (55%) the recurrent disease was found only during routine follow-up procedures. Although the time to detection of recurrence was similar for both asymptomatic and symptomatic cases, progression-free survival after detection in the 16 asymptomatic patients was significantly longer than for the 13 symptomatic patients (P = 0.017); this was found to be especially true in those who underwent chemotherapy as their adjuvant therapy (P = 0.023). CONCLUSIONS: A better prognosis after recurrence was demonstrated in cases that were asymptomatic at the time of recurrence detection than in those in which the tumor was symptomatic. This finding implies that, after the initial surgical resection, intensive follow-up intervention looking for asymptomatic recurrences may significantly improve the prognosis of endometrial carcinoma patients. A further in-depth prospective study is required to establish a standard strategy of follow-up care for endometrial cancer patients.

Tumor characteristics and outcome of uterine carcinosarcoma in women aged ≥80 years.

OBJECTIVE: To examine clinico-pathological characteristics and outcomes of uterine carcinosarcoma (UCS) in women aged ≥80 years. METHODS: This is a secondary analysis of a previous multicenter retrospective study examining 906 women with stage I-IV UCS who underwent primary hysterectomy. Patient demographics, treatment types, tumor characteristics, and survival were examined across aged ≥80 (n = 82 [9.1%]), aged 60-79, (n = 526 [58.1%]), and aged <60 (n = 298 [32.9%]). RESULTS: Women in the aged ≥80 group were more likely to be Caucasian, undergo simple hysterectomy without lymphadenectomy, and receive no postoperative therapy (all, P < 0.05). Tumors in the aged ≥80 group were more likely to have high-grade carcinoma, heterologous sarcoma, and sarcoma dominance but less likely to have lympho-vascular space invasion (all, P < 0.05). Lymphadenectomy did not improve survival in the aged ≥80 group (P > 0.05), whereas lymphadenectomy was protective for survival in the younger groups (both, P < 0.05). Postoperative chemotherapy was associated with improved progression-free survival (PFS) in the aged ≥80 group (hazard ratio [HR] 0.44, 95% confidence interval [CI] 0.22-0.89, P = 0.021). With chemotherapy treatment, women in the aged ≥80 group had PFS similar to those in the aged 60-79 group (HR 0.97, 95%CI 0.51-1.83, P = 0.92). In contrast, without chemotherapy treatment, women in the aged ≥80 group had significantly decreased PFS compared to the aged 60-79 group (HR 1.62, 95%CI 1.09-2.40, P = 0.016). Similar associations were observed for postoperative radiotherapy. CONCLUSION: Nearly 10% of women with UCS are aged ≥80 that are characterized by aggressive tumor factors. Postoperative therapy but not extensive surgery may improve survival in this age group.

LSR Antibody Therapy Inhibits Ovarian Epithelial Tumor Growth by Inhibiting Lipid Uptake.

Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy, but it still lacks effective treatment options. In this study, we utilized proteomic technology to identify lipolysis-stimulated lipoprotein receptor (LSR) as a new tumor antigen of EOC. Immunohistochemical analysis of EOC tissues in conjunction with survival analysis of EOC patients showed that high expression of LSR is associated with poor prognosis. High LSR expression also occurred in tumor metastases including to the lymph node and omentum. To evaluate the possible benefits of blocking this antigen in EOC, we raised a new monoclonal antibody (mAb) to human LSR (hLSR). In mouse xenograft models of hLSR+ EOC (cell lines or patient-derived tumors), we found that administration of anti-hLSR mAb inhibited tumor growth in a manner independent of both antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity. Mechanistic investigations showed that hLSR expression increased incorporation of very-low-density lipoprotein (VLDL) into EOC cells and that anti-hLSR mAb inhibited lipid uptake in vitro and in vivo Moreover, VLDL promoted cell proliferation in hLSR-positive EOC cells in vitro, and this effect was inhibited by anti-hLSR mAb. While the anti-hLSR mAb studied cross reacted with the mouse antigen, we observed no adverse effects on normal organs and lipid metabolism in murine hosts. Our findings suggest that hLSR plays a key functional role in EOC development and that this antigen can be therapeutically targeted by specific mAb to improve EOC treatment.Significance: These findings offer preclinical evidence of the therapeutic efficacy of a novel targeted antibody therapy against deadly epithelial ovarian cancers. Cancer Res; 78(2); 516-27. ©2017 AACR.

Characterizing sarcoma dominance pattern in uterine carcinosarcoma: Homologous versus heterologous element.

OBJECTIVE: To examine significance of sarcoma dominance (SD) patterns in uterine carcinosarcoma (UCS). METHODS: This is a secondary analysis of multicenter retrospective study examining women with stages I-IV UCS who underwent primary surgery. SD was defined as >50% of sarcoma component in uterine tumor. SD patterns were grouped as homologous sarcoma without SD (homo/non-dominance, n = 351), heterologous sarcoma without SD (hetero/non-dominance, n = 174), homologous sarcoma with SD (homo/dominance, n = 175), and heterologous sarcoma with SD (hetero/dominance, n = 189), and correlated to tumor characteristics and survival. RESULTS: SD patterns were significantly associated with age, body habitus, carcinoma type, tumor size, depth of myometrial invasion, and nodal metastasis (all, P < 0.05). On univariate analysis, SD was associated with decreased progression-free survival (PFS) and cause-specific survival (CSS) in homologous cases (both, P < 0.05) but not in heterologous cases. On multivariate models, both homologous and heterologous SD patterns remained independent prognostic factors for decreased PFS (adjusted-hazard ratio [HR] ranges: homo/dominance 1.35-1.69, and hetero/dominance 1.47-1.64) and CSS (adjusted-HR ranges: 1.52-1.84 and 1.66-1.81, respectively) compared to homo/non-dominance (all, P < 0.05). Among stage I-III disease, when tumors had SD, adding radiotherapy to chemotherapy was significantly associated with improved PFS (adjusted-HR: homo/dominance 0.49, and hetero/dominance 0.45) and CSS (0.36 and 0.31, respectively) compared to chemotherapy alone (all, P < 0.05); contrary, this association was not observed with absence of SD (all, P > 0.05). CONCLUSION: In UCS, SD impacts survival in homologous but not in heterologous type. Regardless of sarcoma types, SD was associated with decreased survival in UCS; adding radiotherapy to chemotherapy may be an effective postoperative strategy.

Apoptosis is augmented in high-grade serous ovarian cancer by the combined inhibition of Bcl-2/Bcl-xL and PARP.

The aim of our study was to evaluate possible synergistic cytotoxic effects of the combination treatment with the BH3-mimetic ABT-263 and the PARP inhibitor BMN 673 in high-grade serous ovarian cancer (HGSOC) cells using clinically achievable concentrations of each drug. In vitro cytotoxic effects of ABT-263 and BMN 673 were assessed by XTT assay in three HGSOC cell lines: OVCAR3, OVCAR8, and OV90 cells. Combination index values and synergy/antagonism volumes were used to determine synergy. The drug effects on DNA damage accumulation, cell cycle progression, apoptosis induction, and expression levels of Bcl-2 family proteins were examined to dissect molecular mechanisms. The combination treatment synergistically decreased cell viability in a concentration- and time-dependent manner in all cell lines; combination index values were <0.9 and synergy/antagonism volumes were >100 after 72 h of treatment. Clinically achievable concentrations of ABT-263 2 µM and BMN 673 25 nM were used to investigate mechanisms. No increase in γ-H2AX foci formation was observed with addition of ABT-263 to BMN 673 treatment. The combination treatment increased the sub-G1 and Annexin V-positive cell populations after 48 h compared with the control and each monotherapy. It also induced greater caspase-3/7 activity and PARP cleavage. ABT-263 alone and in combination with BMN 673 induced expression levels of Bim, a pro-apoptotic protein. In conclusion, the ABT-263 and BMN 673 combination resulted in synergistic cytotoxic effects against HGSOC cells through greater induction of apoptosis. This may be a novel therapeutic strategy for HGSOC.

Prexasertib, a cell cycle checkpoint kinases 1 and 2 inhibitor, increases in vitro toxicity of PARP inhibition by preventing Rad51 foci formation in BRCA wild type high-grade serous ovarian cancer.

PARP inhibitors (PARPi) have been effective in high-grade serous ovarian cancer (HGSOC), although clinical activity is limited against BRCA wild type HGSOC. The nearly universal loss of normal p53 regulation in HGSOCs causes dysfunction in the G1/S checkpoint, making tumor cells reliant on Chk1-mediated G2/M cell cycle arrest for DNA repair. Therefore, Chk1 is a reasonable target for a combination strategy with PARPi in treating BRCA wild type HGSOC. Here we investigated the combination of prexasertib mesylate monohydrate (LY2606368), a Chk1 and Chk2 inhibitor, and a PARP inhibitor, olaparib, in HGSOC cell lines (OVCAR3, OV90, PEO1 and PEO4) using clinically attainable concentrations. Our findings showed combination treatment synergistically decreased cell viability in all cell lines and induced greater DNA damage and apoptosis than the control and/or monotherapies (p<0.05). Treatment with olaparib in BRCA wild type HGSOC cells caused formation of Rad51 foci, whereas the combination treatment with prexasertib inhibited transnuclear localization of Rad51, a key protein in homologous recombination repair. Overall, our data provide evidence that prexasertib and olaparib combination resulted in synergistic cytotoxic effects against BRCA wild type HGSOC cells through reduced Rad51 foci formation and greater induction of apoptosis. This may be a novel therapeutic strategy for HGSOC.