BRCA1/2 reversion mutations in a pan-cancer cohort.

Tumor sensitivity to platinum (Pt)-based chemotherapy and poly(adenosine diphosphate ribose) polymerase (PARP) inhibitors is increased by homologous recombination deficiency-causing mutations; in particular, reversion mutations cause drug resistance by restoring protein function. Treatment response is predicted by breast cancer susceptibility gene 1/2 (BRCA1/2) mutations; however, BRCA1/2 reversion mutations have not been comprehensively studied in pan-cancer cohorts. We aimed to characterize BRCA1/2 reversion mutations in a large pan-cancer cohort of Japanese patients by retrospectively analyzing sequencing data for BRCA1/2 pathogenic/likely pathogenic mutations in 3738 patients with 32 cancer types. We identified somatic mutations in tumors or circulating cell-free DNA that could restore the ORF of adverse alleles, including reversion mutations. We identified 12 (0.32%) patients with somatic BRCA1 (n = 3) and BRCA2 (n = 9) reversion mutations in breast (n = 4), ovarian/fallopian tube/peritoneal (n = 4), pancreatic (n = 2), prostate (n = 1), and gallbladder (n = 1) cancers. We identified 21 reversion events-BRCA1 (n = 3), BRCA2 (n = 18)-including eight pure deletions, one single-nucleotide variant, six multinucleotide variants, and six deletion-insertions. Seven (33.3%) reversion deletions showed a microhomology length greater than 1 bp, suggesting microhomology-mediated end-join repair. Disease course data were obtained for all patients with reversion events: four patients acquired mutations after PARP-inhibitor treatment failure, two showed somatic reversion mutations after disease progression, following Pt-based treatment, five showed mutations after both treatments, one patient with pancreatic cancer and BRCA1 reversion mutations had no history of either treatment. Although reversion mutations commonly occur in BRCA-associated cancers, our findings suggest that reversion mutations due to Pt-chemotherapy might be correlated with BRCA1/2-mediated tumorigenesis even in non-BRCA-associated histologies.

Clinical availability and characteristics of multigene panel testing for recurrent/advanced gynecologic cancer.

BACKGROUND: Japan's health insurance covers multigene panel testing. This study aimed to determine the potential availability and utility of gene panel testing clinically in gynecologic oncology. METHODS: We analyzed the characteristics of patients with gynecologic cancer who underwent gene panel testing using FoundationOne® CDx or OncoGuide™ NCC Oncopanel between November 2019 and October 2022. RESULTS: Out of 102 patients analyzed, 32, 18, 43, 8, and 1 had cervical, endometrial, ovarian cancers, sarcoma, and vaginal cancer, respectively. Druggable gene alteration was found in 70 patients (68.6%; 21 with cervical cancer, 15 with endometrial cancer, 28 with ovarian cancer, 5 with sarcoma, and 1 with other). The most common druggable gene alteration was PIK3CA mutation (n = 21), followed by PTEN mutation (n = 12) and high tumor mutation burden (TMB-H) (n = 11). TMB-H was detected in 5 patients with cervical cancer, 5 with endometrial cancer, and 1 with endometrial stromal sarcoma. Eleven patients (10.8%) received molecularly targeted therapy according to their gene aberrations. Gene panel testing was mostly performed when the second-line treatment was ineffective. Of all 102 patients, 60 did not have recommended treatment, and 15 died or had worsened conditions before obtaining the test results. CONCLUSION: Through multigene panel testing, although many patients had druggable gene alterations, 10.8% of them received the recommended treatment. TMB-H was mainly observed in cervical/endometrial cancer, suggesting its potential as a therapeutic biomarker of immune checkpoint inhibitors. Furthermore, patients' prognosis and performance status should be considered before performing the test.

Real-world application of next-generation sequencing-based test for surgically resectable colorectal cancer in clinical practice.

Aim: To evaluate the significance of next-generation sequencing-based gene panel testing in surgically resectable colorectal cancer by analyzing real-world data. Materials & methods: A total of 107 colorectal cancer patients who underwent curative surgery were included, and correlations between next-generation sequencing data and clinicopathological findings were evaluated. Results: More combination patterns in gene alteration were identified in advanced-stage tumors than in early-stage tumors. The copy number alteration count was significantly lower in right-sided colon tumors and early-stage tumors. Homologous recombination deficiency was more often identified in advanced-stage tumors, and high homologous recombination deficiency status was useful for identifying high-risk stage II tumors. Conclusion: Homologous recombination deficiency was identified as a useful result of gene panel testing with novel utility in clinical practice.

Efficacy and safety of olaparib maintenance monotherapy for Japanese patients with platinum-sensitive relapsed ovarian, fallopian tube, and primary peritoneal cancer.

BACKGROUND: Olaparib maintenance therapy for platinum-sensitive relapsed ovarian cancer has been approved in Japan since April 2018. Here, we report the experience administering this therapy in our hospital, with the aim of evaluating efficacy and safety in the Japanese population. METHODS: The study included 52 patients with platinum-sensitive relapsed ovarian, fallopian tube, and primary peritoneal cancer. All patients started olaparib at a dose of 300 mg twice daily. Information about treatment efficacy and adverse effects was collected retrospectively from medical records. RESULTS: Median age was 58 years old (range: 33-80), and 82.7% of the patients were diagnosed with high-grade serous carcinoma. Sixteen patients (30.8%) possessed the BRCA1/2 pathogenic variant (15 germline and 1 tissue), 3 (5.8%) possessed variants of unknown significance (2 germline and 1 tissue), 16 (30.8%) possessed wild type, and 17 (32.7%) were not analyzed. Median progression-free survival was 15.3 months (95% CI 9.0-21.6). Patients with BRCA1/2 pathogenic variants showed significantly longer PFS than patients with wild-type BRCA1/2 (p = 0.007). Disease progression caused 34 cases to discontinue olaparib. Eighteen (34.6%) individuals exhibited ≥ grade 3 anemia, although they recovered in response to appropriate management. One patient discontinued olaparib because of prolonged renal dysfunction. Another patient presented with grade 3 fatigue, but recovered after 2 weeks of interruption and continued olaparib treatment. CONCLUSION: Olaparib maintenance therapy for platinum-sensitive recurrent ovarian cancer in the Japanese population is sufficiently safe and no less effective than reports from previous studies.

Sentinel node navigation surgery in cervical cancer: a systematic review and metaanalysis.

Sentinel node navigation surgery (SNNS) is used in clinical practice for the treatment of cervical cancer. This study aimed to elucidate the appropriate sentinel lymph node (SLN) mapping method and assess the safety and benefits of SNNS. We searched the PubMed, Ichushi, and Cochrane Library databases for randomized controlled trials (RCT) and studies on SLN in cervical cancer from January 2012 to December 2020. Two authors independently assessed study quality and extracted data. We quantitatively analyzed the detection rate, sensitivity/specificity, and complications and reviewed information, including the survival data of SLN biopsy (SLNB) without pelvic lymphadenectomy (PLND). The detection rate of SLN mapping in the unilateral pelvis was median 95.7% and 100% and in the bilateral pelvis was median 80.4% and 90% for technetium-99 m (Tc) with/without blue dye (Tc w/wo BD) and indocyanine green (ICG) alone, respectively. The sensitivity and specificity of each tracer were high; the area under the curve of each tracer was 0.988 (Tc w/wo BD), 0.931 (BD w/wo Tc), 0.966 (ICG), and 0.977 (carbon nanoparticle). Morbidities including lymphedema, neurological symptoms and blood loss were associated with PLND. One RCT and five studies all showed SNNS without systematic PLND does not impair recurrence or survival in early-stage cervical cancer with a tumor size ≤ 2-4 cm. Both Tc w/wo BD and ICG are appropriate SLN tracers. SNNS can reduce the morbidities associated with PLND without affecting disease progression in early-stage cervical cancer.

Prospective feasibility study of neoadjuvant dose-dense paclitaxel plus carboplatin with bevacizumab therapy followed by interval debulking surgery for advanced ovarian, fallopian tube, and primary peritoneal cancer patients.

BACKGROUND: This study aimed to investigate the clinical benefit of dose-dense paclitaxel plus carboplatin (TC) with bevacizumab therapy for advanced ovarian, fallopian tube, and primary peritoneal cancer patients in the neoadjuvant setting. METHODS: Ovarian, fallopian tube or primary peritoneal cancer patients with stage III-IV disease received neoadjuvant chemotherapy (NAC) every 3 weeks consisting of paclitaxel (80 mg/m2) on days 1, 8, and 15; carboplatin (AUC 6.0 mg/mL × min.) on day 1; and bevacizumab (15 mg/kg) on day 1. Interval debulking surgery (IDS) was performed after 3 cycles of dose-dense TC-bevacizumab therapy. The primary endpoint was the rate of complete resection by IDS. Secondary endpoints were treatment completion rate, treatment exposure, response rate to NAC, adverse events, and perioperative complications. RESULTS: Twenty-four patients were included in this study. The median age was 55.5 years (37-80 years), and most patients had high-grade serous carcinoma accounted (n = 18). IDS was performed in all patients with complete resection achieved in 75% (95% confidence interval: 57.7-92.3%). The lower limit exceeded the preset threshold rate of 55%. The response rate to NAC was 79%, and serum CA125 levels were in the normal range after NAC in 57% of patients. Grade 4 hematological toxicities and grade 3/4 non-hematological toxicities occurred in 29% and 17% of patients during NAC, respectively. Grade 3/4 perioperative complications were seen in 29% of patients, but no gastrointestinal perforations or treatment-related deaths occurred. CONCLUSIONS: Neoadjuvant dose-dense TC-bevacizumab therapy was well tolerated, and a satisfactory rate of complete resection by IDS was achieved.

Characteristics and clinicopathological features of patients with ovarian metastasis of endometrial cancer: a retrospective study.

There are no criteria for patient selection for ovarian-preserving surgery for endometrial cancer (EC). In this study, intraoperative findings of ovarian swelling (OvS) and the clinicopathological features of patients with EC with or without ovarian metastasis were analysed to identify risk factors for ovarian metastasis. Patients who underwent surgery for EC between 2012 and 2019 at our hospital were enrolled. In univariate analysis, all features were significantly higher in metastasis(+) cases. In multivariate analysis, lymphatic space invasion (LSI), cervical stromal involvement (CSI), peritoneal dissemination, and OvS were significant risk factors. In univariate analysis in stage I and II cases classified without adnexal pathological factors, type 2 histologic type, LSI, CSI, and OvS were significantly higher in metastasis(+) cases. LSI, CSI, and OvS were significant risk factors in multivariate analysis. Patients with type 1 histologic type EC without myometrial invasion ≥1/2, CSI and extrauterine lesions are appropriate for ovarian preservation. IMPACT STATEMENTWhat is already known on this subject? The number of premenopausal patients with endometrial cancer (EC) is increasing. Bilateral oophorectomy for EC results in surgical primary ovarian insufficiency, and thus, surgery with ovarian preservation has been examined. However, there are few reports on risk factors for ovarian metastasis of EC and no established criteria for patient background or pathological factors to determine suitability for ovarian preservation surgery.What do the results of this study add? In univariate analysis, all pathological findings suggestive of disease progression were more frequent in cases with ovarian metastases. In multivariate analysis, lymphatic space invasion (LSI), cervical stromal involvement (CSI), peritoneal dissemination, and ovarian swelling (OvS) were identified as significant risk factors for ovarian metastasis. In an analysis of stage I and II cases classified without adnexal pathological factors, type 2 histologic type, LSI, CSI, and OvS were significantly more common in cases with ovarian metastasis, and LSI, CSI, and OvS emerged as significant risk factors for ovarian metastasis in multivariate analysis.What are the implications of these findings for clinical practice and/or further research? Patients with type 1 histologic type EC without depth of myometrial invasion ≥1/2, CSI, or extrauterine lesions may be appropriate cases for ovarian preservation.

ARID1A mutation/ARID1A loss is associated with a high immunogenic profile in clear cell ovarian cancer.

OBJECTIVES: ARID1A mutation is frequently found in clear cell ovarian cancer (CCC) and endometrioid ovarian cancer (EC). Anti-PD-1 monotherapy has been found to have limited efficacy in epithelial ovarian cancer; however, anti-PD-1 therapy showed significant clinical benefit in some CCC. We sought to define the relationship of ARID1A mutation/ARID1A expression to the immunogenic profile of different histologic subtypes of ovarian cancer. METHODS: We performed next-generation sequencing of 160 cancer-related genes. Also, we analyzed the immunohistochemical status of ARID1A, PD-L1, and CD8 with survival in different histologic subtypes of ovarian cancer in a total of 103 cases. RESULTS: ARID1A mutation was found in 0% of the high-grade serous ovarian cancer (HGSC) (n = 36), 41.5% of the CCC (n = 41), 45.0% of the EC (n = 20), and 33.3% of the mucinous ovarian cancer (MC) (n = 6) cases. ARID1A loss was found in 19.4% of the HGSC, 75.6% of the CCC, 60.0% of the EC and 0% of the MC cases. ARID1A mutation was found to be associated with high PD-L1 (p < 0.001) or CD8 levels (p < 0.001) in CCC but not in other histologic subtypes. Meanwhile, ARID1A loss was associated with high PD-L1 or CD8 levels in CCC (p < 0.001) and HGSC (p < 0.001) but not in EC and MC. In addition, ARID1A mutation was associated with high tumor mutation burden in CCC (p = 0.006). CONCLUSIONS: ARID1A mutation/ARID1A expression is associated with immune microenvironmental factors in CCC but not in EC. ARID1A status can be a biomarker for selecting candidates for immune checkpoint blockade in CCC.

Retrospective evaluation of risk-reducing salpingo-oophorectomy for BRCA1/2 pathogenic variant carriers among a cohort study in a single institution.

BACKGROUND: Risk-reducing salpingo-oophorectomy is performed for the primary prevention of ovarian cancer in patients with hereditary breast-ovarian cancer syndrome. We performed risk-reducing salpingo-oophorectomy for the first time in Japan in 2008, and we experienced 20 cases of risk-reducing salpingo-oophorectomy through 2019. In the past, the use of risk-reducing salpingo-oophorectomy in Japan was restricted because it was not covered by a Japanese National Health Insurance. Since April 2020, risk-reducing salpingo-oophorectomy has been covered by insurance for patients with breast-ovarian cancer syndrome and pre-existing breast cancer, and this surgery is expected to become more widely implemented in Japan. METHODS: To contribute to the widespread use of risk-reducing salpingo-oophorectomy in the future, we retrospectively reviewed 20 cases of risk-reducing salpingo-oophorectomy at our hospital cohort study to clarify the issues in its implementation. RESULTS: The variant genes for which risk-reducing salpingo-oophorectomy was indicated were BRCA1 and BRCA2 in 13 (65%) and 7 patients (35%), respectively. The median age at which risk-reducing salpingo-oophorectomy was performed was 49 years (range, 38-58), 13 patients (65%) had gone through menopause, and 16 patients (80%) had a history of breast cancer. Of the five patients (25%) with vasomotor symptoms, four received Chinese medicine, and only one received hormone replacement therapy. Occult cancer was detected in the removed ovaries in two patients (10%), although no postoperative peritoneal carcinogenesis has been observed to date. CONCLUSIONS: Women who paid for risk-reducing salpingo-oophorectomy out of pocket were older than the recommended age at which the procedure should be performed, and this may explain the higher rate of occult cancers than previously reported. We need to perform risk-reducing salpingo-oophorectomy at the recommended age to ensure that the procedure is effective for primary prevention.

A prospective cohort study on the safety and efficacy of bevacizumab combined with chemotherapy in Japanese patients with relapsed ovarian, fallopian tube or primary peritoneal cancer.

OBJECTIVE: this prospective cohort study aimed to assess the safety and efficacy of bevacizumab combined with chemotherapy in Japanese patients with relapsed ovarian, fallopian tube or primary peritoneal cancer. METHODS: in this study, 40 Japanese patients with relapsed ovarian, fallopian tube or primary peritoneal cancer selected to receive bevacizumab with chemotherapy were enrolled. Patients in poor general condition were excluded. Each patient was monitored prospectively for adverse events, administration status, disease status and survival. Treatment was continued until intolerable adverse events or disease progression. The primary endpoint was safety. RESULTS: bevacizumab plus platinum-based chemotherapy was performed for 30 patients (median cycle; 16.5), while bevacizumab plus non-platinum chemotherapy was performed for 10 patients (median cycle; 5.5). Among bevacizumab-related adverse events, hypertension occurred in 80% of patients, proteinuria in 83%, mucositis in 25%, bleeding in 20%, thromboembolic events in 5.0% and fistula in 2.5%. Gastrointestinal perforation or other life-threatening lethal adverse events were not observed. Response rate and median progression-free survival were 73% and 19.3 months for patients with bevacizumab plus platinum-based chemotherapy, and 30% and 3.9 months for patients with bevacizumab plus non-platinum chemotherapy, respectively. There was no correlation between response rate and occurrence of adverse events such as hypertension or proteinuria. CONCLUSION: bevacizumab combined with chemotherapy was tolerable and effective for Japanese patients with relapsed ovarian cancer, fallopian tube cancer or primary peritoneal cancer. Hypertension and proteinuria are frequently occurred and managed properly for continuing treatment.

Atypical vessels in hysteroscopy: Usefulness in prediction of malignant diseases in patients treated with tamoxifen.

AIM: Tamoxifen (TAM) is widely used in adjuvant endocrine therapy for invasive breast cancer as a selective estrogen modulator, but this treatment has a risk of developing endometrial malignancy. However, hysteroscopic findings during or after TAM treatment are unclear. The aim of this study is to examine the association between hysteroscopic patterns and malignant histological findings during or after treatment with TAM. METHODS: The subjects were patients who received TAM after surgery for breast cancer and underwent hysteroscopy at our institution from January 2016 to December 2019. Clinicopathological factors and hysteroscopic findings were collected from medical records and investigated retrospectively. Histologically, atypical endometrial hyperplasia, endometrial cancer, and carcinosarcoma were classified as malignant diseases. RESULTS: A total of 26 patients were eligible for the study. Hysteroscopic findings included an irregular surface of the endometrium (n = 3, 11.5%), atypical vessels (n = 10, 38.5%), papillary structure (n = 3, 11.5%), and polypoid structure (n = 18, 69.2%). Histological examination revealed malignancy in six patients (23.0%). The percentage of atypical vessels in patients with malignancies was significantly higher than that in patients with a normal endometrium or benign lesion (100% vs. 20%, p = 0.0009). The sensitivity and specificity of atypical vessels in hysteroscopy for diagnosis of malignant diseases were 100% and 80%, respectively. CONCLUSIONS: Hysteroscopic findings of atypical vessels may be useful for prediction of malignant diseases in patients treated with TAM.

Hysteroscopic Transcervical Resection for Atypical Polypoid Adenomyoma of the Uterus: A Valid, Fertility-Preserving Option.

STUDY OBJECTIVE: To evaluate hysteroscopic transcervical resection (TCR) for atypical polypoid adenomyoma of the uterus (APA). DESIGN: Retrospective study (Canadian Task Force classification II-2). SETTING: Single tertiary hospital. PATIENTS: Women who underwent TCR for APA at Kawasaki Municipal Hospital between 2003 and 2015. INTERVENTIONS: Clinical records were obtained. MEASUREMENTS AND MAIN RESULTS: Thirty-five patients with APA were evaluated. The median patient age was 35 years (range, 23-43 years), and the median tumor diameter was 22 mm (range, 9-51 mm). The median duration of observation after the first TCR was 34.0 months (range, 4.2-133.7 months). In 19 patients, the tumor recurred after the first TCR. A second TCR was performed in 13 patients, 11 of whom experienced recurrence. A third TCR was performed in 7 patients, all 7 of whom experienced recurrence. A fourth TCR was performed in 4 patients, 3 of whom experienced recurrence. The recurrence rate after the second TCR was higher than that after the first TCR (71.4%-84.6% vs 54.3%; p < .01, t test). The median disease-free interval was 12.4 months after the first TCR, 15.3 months after the second TCR, 10.5 months after the third TCR, and 10.9 months after the fourth TCR. Seven patients progressed to endometrial cancer; however, there was no mortality. Six of the 35 patients conceived, and 4 had a normal spontaneous delivery. CONCLUSION: Owing to disease-free intervals that follow treatment, TCR is a promising treatment modality as a fertility-preserving option for patients with APA under careful observation. Twenty percent of patients with APA develop cancer; however, the present study showed no mortality.

Elevated preoperative neutrophil : lymphocyte ratio as a preoperative indicator of mature cystic teratoma with malignant transformation.

AIM: To examine the usefulness of the neutrophil : lymphocyte (N/L) ratio as a cost-effective and simple diagnostic marker of mature cystic teratoma (MCT) with malignant transformation (MT). METHODS: A retrospective chart review was performed between 1998 and 2013 of 12 MCT patients with MT and between 2009 and 2013 of 130 patients with benign MCT. Data were collected on age, tumor size, white blood cell count with differential counts, tumor marker levels, and presenting features. RESULTS: Older age, greater tumor size, higher CA19-9 or CA125, higher neutrophil count, and higher N/L ratio were associated with MT on univariate analysis. White blood cell count; lymphocyte count; and the tumor marker squamous cell carcinoma antigen were not associated with MT. Older age (≥median), larger tumor size (≥10 cm), and high N/L ratio (≥5.0) were predictors of MT (hazard ratio, 11.51, 5.87, and 11.11, respectively). Six of 12 patients were diagnosed with MT on preoperative magnetic resonance imaging and five of 12 had an N/L ratio ≥5.0. CONCLUSIONS: Neutrophil : lymphocyte ratio is a potential preoperative diagnostic marker of MT. The optimal cut-off should be determined in future large-scale studies.

Simultaneous analysis of the gene expression profiles of cancer and stromal cells in endometrial cancer.

To address the role of cancer-stroma interactions, we performed gene expression profiling of both cancer and stroma, using matching samples of endometrial cancer (EC), and analyzed the relationship between the gene expression pattern and prognosis in EC. Sixty EC cases were included in this study (38 nonrecurrent and 22 recurrent). Cancer and stroma were separated by performing laser capture microdissection, and microarray analysis was performed separately on cancer and stromal cells. Genes related with progression-free survival (PFS) in cancer and stroma were analyzed using the Cox regression model, and we established a formula, based on the gene expression pattern of cancer and stroma, to predict recurrence using logistic regression. We estimated the accuracy of the formula using the 0.632 method. All cases were classified based on the 79 selected genes of cancer and stroma related to PFS, based on unsupervised clustering. A total of 143 genes in cancer, and 79 genes in stroma were significantly related with PFS. The estimated area under the curve of receiver operating characteristics curve in cancer and stroma to predict recurrence were 0.800 and 0.758, respectively. Based on the 79 genes of cancer, the 22 recurrent cases were divided into two groups, which generally correlated with the histological grade. In contrast, based on the 79 genes of stroma, the 22 recurrent cases displayed homogeneous gene expression, unrelated to the histological grade. We conclude that gene expression profiles of cancer and stroma can predict the recurrence of EC and stromal that gene expression does not depend on the cancer grade.

Induction of ZEB proteins by inactivation of RB protein is key determinant of mesenchymal phenotype of breast cancer.

We previously showed that depletion of the retinoblastoma protein (RB) induces down-regulation of the adhesion molecule E-cadherin and thereby triggers the epithelial-mesenchymal transition. To further characterize the effect of RB inactivation on the phenotype of cancer cells, we have now examined RB expression in human breast cancer cell lines and clinical specimens. We found that RB-inactive cells exhibit a mesenchymal-like morphology and are highly invasive. We also found that ZEB proteins, transcriptional repressors of the E-cadherin gene, are markedly up-regulated in these cells in a manner sensitive to the miR-200 family of microRNAs. Moreover, depletion of ZEB in RB-inactive cells suppressed cell invasiveness and proliferation and induced epithelial marker expression. These results implicate ZEB in induction of the epithelial-mesenchymal transition, as well as in maintenance of the mesenchymal phenotype in RB-inactive cells. We also developed a screening program for inhibitors of ZEB1 expression and thereby identified several cyclin-dependent kinase inhibitors that blocked both ZEB1 expression and RB phosphorylation. Together, our findings suggest that RB inactivation contributes to tumor progression not only through loss of cell cycle control but also through up-regulation of ZEB expression and induction of an invasive phenotype.

The APC/C activator Cdh1 regulates the G2/M transition during differentiation of placental trophoblast stem cells.

Differentiation of placental trophoblast stem (TS) cells to trophoblast giant (TG) cells is accompanied by transition from a mitotic cell cycle to an endocycle. Here, we report that Cdh1, a regulator of the anaphase-promoting complex/cyclosome (APC/C), negatively regulates mitotic entry upon the mitotic/endocycle transition. TS cells derived from homozygous Cdh1 gene-trapped (Cdh1(GT/GT)) murine embryos accumulated mitotic cyclins and precociously entered mitosis after induction of TS cell differentiation, indicating that Cdh1 is required for the switch from mitosis to the endocycle. Furthermore, the Cdh1(GT/GT) TS cells and placenta showed aberrant expression of placental differentiation markers. These data highlight an important role of Cdh1 in the G2/M transition during placental differentiation.

The origin of stroma surrounding epithelial ovarian cancer cells.

Cancer stroma is thought to play an important role in tumor behavior, including invasion or metastasis and response to therapy. Cancer stroma is generally thought either to be non-neoplastic cells, including tissue-marrow or bone-marrow-derived fibroblasts, or to originate in epithelial mesenchymal transition of cancer cells. In this study, we evaluated the status of the p53 gene in both the cancer cells and the cancer stroma in epithelial ovarian cancer (EOC) to elucidate the origin of the stroma. Samples from 16 EOC patients were included in this study. Tumor cells and adjacent nontumor stromal cells were microdissected and DNA was extracted separately. We analyzed p53 sequences (exons 5-8) of both cancer and stromal tissues in all cases. Furthermore, we examined p53 protein expression in all cases. Mutations in p53 were detected in 9 of the 16 EOCs: in 8 of these cases, the mutations were detected only in cancer cells. In 1 case, the same mutation (R248Q) was detected in both cancer and stromal tissues, and p53 protein expression was detected in both the cancer cells and the cancer stroma. Most cancer stroma in EOC is thought to originate from non-neoplastic cells, but some parts of the cancer stroma might originate from cancer cells.

EGRI and FOSB gene expressions in cancer stroma are independent prognostic indicators for epithelial ovarian cancer receiving standard therapy.

Stromal components interact with cancer cells to promote growth and metastasis. The purpose of this study was to identify genes expressed in stroma, which could provide prognostic information in epithelial ovarian cancer (EOC). Seventy-four patients were included. We performed gene expression profiling and confirmed array data using RT-PCR and immunohistochemistry. By microarray analysis, 52 candidate genes associated with progression free survival (PFS) were identified (P < 0.005). Expression of the early growth response 1 (EGR1) and FBJ murine osteosarcoma viral oncogene homolog B (FOSB) genes was further analyzed. Array data were confirmed by RT-PCR and multivariate analysis demonstrated that both EGR1 and FOSB expression in cancer stroma, and EGR1 expression in cancer are independent prognostic factors in EOC. Immunohistochemically, EGR1 protein is localized in cancer cells and α-smooth muscle actin positive stromal fibroblasts. The EGR1 and FOSB expression in stromal cells and EGR1 expression in cancer cells are prognostic indicators in EOC.

Expression profiles of carcinosarcoma of the uterine corpus-are these similar to carcinoma or sarcoma?

Uterine carcinosarcoma (CS) is usually classified as uterine endometrial carcinoma (EC). However, CS is more aggressive even compared with high grade EC. CS is also reported to undergo epithelial to mesenchymal transition (EMT). In this study, we compared the gene expression profiles of CS, EC, and uterine sarcoma (US) and evaluated the role of EMT and chromosomal aberrations in CS tumor formation. Frozen tissues of 46 patients (14 CS, 24 EC, and 8 US) were included. The similarity was examined by Gene Set Enrichment Analysis (GSEA), Fisher's exact test, and clustering using "intrinsic gene set". We examined the expression of 39 EMT-related genes and evaluated TGF-beta signaling by phospho-SMAD2/3 (p-SMAD2/3) staining. Chromosomal regions differing between CS and EC were identified by chromosomal GSEA and comparative genomic hybridization (CGH) microarrays. Three statistical methods confirmed that CS resembled US rather than EC. Acquired markers of EMT were upregulated and attenuated markers of EMT were downregulated in CS. Immunohistochemistry showed that carcinomatous region of CS have higher expression of p-SMAD2/3 than EC (P = 0.008). Chromosomal GSEA showed that genes located at 19q13 had higher expression in CS. Furthermore, CGH microarray indicated that the TGFB1 locus at 19q13.1 was amplified in 4 of 7 samples. Based on the expression profile, CS resembles US rather than EC. TGF-beta signaling is activated in CS and chromosomal gains at 19q13, which includes the TGFB1 locus, suggest that this may contribute to high expression of TGF-beta and thereby EMT phenotype of CS.