A controlled ovarian stimulation procedure suitable for cynomolgus macaques

This study aimed to develop a more suitable ovarian stimulation procedure for cynomolgus macaques (Macaca fascicularis). Macaques were divided into 4 groups, 7AG, 8AG, 7AN, and 8AN, according to the ovarian stimulation procedure administered (i.e., administration of either a gonadotropin-releasing hormone agonist [GnRH-a] or GnRH antagonist [GnRH-ant]) and the number of menstruations (≤ 7 times or ≥ 8 times) in the previous year. In both procedures, oocyte growth and maturation were induced by administration of human follicle-stimulating hormone and human chorionic gonadotropin. The mean numbers of metaphase II mature and metaphase I premature oocytes collected from the 7AG, 8AG, 7AN, and 8AN groups were 12.1 and 10.4, 12.0 and 13.8, 9.1 and 8.3, and 15.5 and 8.8, respectively (P>0.05). The fertilization rates of the 7AN and 8AN groups (85.3% and 74.7%) tended to be higher compared with those in the 7AG and 8AG groups (59.1% and 47.3%; P>0.05). The 8AN group yielded 19.9 zygotes, which was the largest number per macaque, compared with the other three groups. Furthermore, regarding the decreases in body weight between the start of the procedures and the time of oocyte collection, those of the 7AN and 8AN groups were significantly smaller than those of the 7AG and 8AG groups (P<0.05), suggesting that the procedure involving GnRH-ant reduced the burden on the macaques. Thus, controlled ovarian stimulation using a GnRH-ant has some advantages for cynomolgus macaques compared with that using a GnRH-a.     

CA-125 monitoring during chemotherapy for ovarian cancer

Serum CA-125 was determined in 60 patients with variously extended ovarian cancer and monitored during and after chemotherapy. The study indicates that: 1) prechemotherapy CA-125 shows the presence of an active disease with an accuracy greater than 85%. The antigen is elevated in 97% of patients with greater than 2 cm disease, but sensitivity is low (67%) in patients with minimal residual disease (less than 2 cm); 2) changes in CA-125 correspond well with the response to chemotherapy. CA-125 becomes negative in every patient having clinical CR and increases in every patient with progressive disease. These changes can indicate the type of response some months ahead of time; 3) CA-125 indicates in advance the recurrence of the disease after an objective remission: 4) In the conditions studied CA-125 basal levels do not seem to have prognostic value as regarding either response or survival.     

Enhancing chemotherapy response with Bmi-1 silencing in ovarian cancer

Undoubtedly ovarian cancer is a vexing, incurable disease for patients with recurrent cancer and therapeutic options are limited. Although the polycomb group gene, Bmi-1 that regulates the self-renewal of normal stem and progenitor cells has been implicated in the pathogenesis of many human malignancies, yet a role for Bmi-1 in influencing chemotherapy response has not been addressed before. Here we demonstrate that silencing Bmi-1 reduces intracellular GSH levels and thereby sensitizes chemoresistant ovarian cancer cells to chemotherapeutics such as cisplatin. By exacerbating ROS production in response to cisplatin, Bmi-1 silencing activates the DNA damage response pathway, caspases and cleaves PARP resulting in the induction apoptosis in ovarian cancer cells. In an in vivo orthotopic mouse model of chemoresistant ovarian cancer, knockdown of Bmi-1 by nanoliposomal delivery significantly inhibits tumor growth. While cisplatin monotherapy was inactive, combination of Bmi-1 silencing along with cisplatin almost completely abrogated ovarian tumor growth. Collectively these findings establish Bmi-1 as an important new target for therapy in chemoresistant ovarian cancer.     

Serum selenium concentrations in ovarian cancer patients using a simplified fluorimetric procedure

The serum selenium (Se) concentrations were determined to be 105.6±15.6 μg/L ( ) and 116.7±18.4 μg/L ( ) for the ovarian cancer patients and the control subjects in Singapore, respectively (p<0.0065). When we separated the patients into three age groups, namely <30, 30–50, and >50 yr, the ovarian cancer patients showed significantly lower mean serum Se levels than the control subjects for the 30–50-yr age group only. However, when the analysis of variance was used to evaluate the data, the values indicated that the age of the subject did not significantly affect the serum Se level. Our findings suggest that there is an inverse relationship between serum Se concentration and the incidence of human ovarian cancer. A modified simple fluorimetric method for the determination of serum Se concentration is described. The procedure, with a sensitivity limit of 5 μg/L and percentage recoveries of 96.2–100.7%, requires only 0.2 mL of serum sample.     

MiR-135b improves proliferation and regulates chemotherapy resistance in ovarian cancer

Journal of Molecular Histology - MicroRNAs act as regulators in ovarian tumorigenesis and progression by involving different molecular pathways. Here, we examined the role of miR-135b on growth,...     

ZNF76 predicts prognosis and response to platinum chemotherapy in human ovarian cancer

Ovarian cancer (OV) is the most lethal gynecologic malignancy. One major reason of the high mortality of the disease is due to platinum-based chemotherapy resistance. Increasing evidence reveal the important biological functions and clinical significance of zinc finger proteins (ZNFs) in OV. In the present study, the relationship between the zinc finger protein 76 (ZNF76) and clinical outcome and platinum resistance in patients with OV was explored. We further analyzed ZNF76 expression via multiple gene expression databases and identified its functional networks using cBioPortal. RT-qPCR and IHC assay shown that the ZNF76 mRNA and protein expression were significantly lower in OV tumor than that in normal ovary tissues. A strong relationship between ZNF76 expression and platinum resistance was determined in patients with OV. The low expression of ZNF76 was associated with worse survival in OV. Multivariable analysis showed that the low expression of ZNF76 was an independent factor predicting poor outcome in OV. The prognosis value of ZNF76 in pan-cancer was validated from multiple cohorts using the PrognoScan database and GEPIA 2. A gene-clinical nomogram was constructed by multivariate cox regression analysis, combined with clinical characterization and ZNF76 expression in TCGA. Functional network analysis suggested that ZNF76 was involved in several biology progressions which associated with OV. Ten hub genes (CDC5L, DHX16, SNRPC, LSM2, CUL7, PFDN6, VARS, HSD17B8, PPIL1, and RGL2) were identified as positively associated with the expression of ZNF76 in OV. In conclusion, ZNF76 may serve as a promising prognostic-related biomarker and predict the response to platinum in OV patients.     

Type of chemotherapy has substantial effects on the immune system in ovarian cancer

Chemotherapy induces a variety of immunological changes. Studying these effects can reveal opportunities for successful combining chemotherapy and immunotherapy. Immuno-chemotherapeutic combinations in ovarian cancer are currently not generating the anticipated positive effects. To date, only scattered and inconsistent information is available about the immune-induced changes by chemotherapy in ovarian cancer. In this study, we compared six common chemotherapeutics used in ovarian cancer patients (carboplatin, paclitaxel, pegylated liposomal doxorubicin, gemcitabine, carboplatin-paclitaxel and carboplatin-gemcitabine) and studied their effects on the immune system in an ovarian cancer mouse model. Mice received a single chemotherapy or vehicle injection 21 days after tumor inoculation with ID8-fluc cells. One week after therapy administration, we collected peritoneal washings for flow cytometry, serum for cytokine analysis with cytometric bead array and tumor biopsies for immunohistochemistry. Carboplatin-paclitaxel showed the most favorable profile with a decrease in immunosuppressive cells in the peritoneal cavity and an increase of interferon-gamma in serum. In contrast, carboplatin-gemcitabine seemed to promote a hostile immune environment with an increase in regulatory T-cells in tumor tissue and an increase of macrophage-inflammatory-protein-1-beta in the serum.     

BRCA1 epigenetic inactivation predicts sensitivity to platinum-based chemotherapy in breast and ovarian cancer

Germline mutations in the BRCA1 or BRCA2 genes are associated with an increased risk of breast and ovarian cancer development. Both genes are involved in DNA repair, and tumors harboring genetic defects in them are thought to be more sensitive to DNA-damaging agents used in chemotherapy. However, as only a minority of breast and ovarian cancer patients carry BRCA1 or BRCA2 mutations, few patients are likely to benefit from these pharmacogenetic biomarkers. Herein, we show that, in cancer cell lines and xenografted tumors, BRCA1 CpG island promoter hypermethylation-associated silencing also predicts enhanced sensitivity to platinum-derived drugs to the same extent as BRCA1 mutations. Most importantly, BRCA1 hypermethylation proves to be a predictor of longer time to relapse and improved overall survival in ovarian cancer patients undergoing chemotherapy with cisplatin.     

BRCA1 epigenetic inactivation predicts sensitivity to platinum-based chemotherapy in breast and ovarian cancer

Germline mutations in the BRCA1 or BRCA2 genes are associated with an increased risk of breast and ovarian cancer development. Both genes are involved in DNA repair, and tumors harboring genetic defects in them are thought to be more sensitive to DNA-damaging agents used in chemotherapy. However, as only a minority of breast and ovarian cancer patients carry BRCA1 or BRCA2 mutations, few patients are likely to benefit from these pharmacogenetic biomarkers. Herein, we show that, in cancer cell lines and xenografted tumors, BRCA1 CpG island promoter hypermethylation-associated silencing also predicts enhanced sensitivity to platinum-derived drugs to the same extent as BRCA1 mutations. Most importantly, BRCA1 hypermethylation proves to be a predictor of longer time to relapse and improved overall survival in ovarian cancer patients undergoing chemotherapy with cisplatin.