Effect of human endogenous retrovirus-K env gene knockout on proliferation of ovarian cancer cells.

BACKGROUND: Among various human endogenous retroviruses (HERVs), the HERV-K (HML-2) group has been reported to be highly related to cancer. In pancreatic cancer cells, shRNA-mediated downregulation of HERV-K env RNA decreases cell proliferation and tumor growth through the RAS-ERK-RSK pathway; in colorectal cancer, CRISPR-Cas9 knockout (KO) of the HERV-K env gene affects tumorigenic characteristics through the nupr-1 gene. OBJECTIVE: The effect of HERV-K env KO has not been studied in ovarian cancer cell lines. In this study, we analyzed the tumorigenic characteristics of ovarian cancer cell lines, including cell proliferation, migration, and invasion, and the expression patterns of related proteins after CRISPR-Cas9 KO of the HERV-K env gene. METHODS: The HERV-K env gene KO was achieved using the CRISPR-Cas9 system in ovarian cancer cell lines SKOV3 and OVCAR3. Tumorigenic characteristics including cell proliferation, migration, and invasion were analyzed, and related protein expression was investigated by western blot analysis. RESULTS: The expression of the HERV-K env gene in KO cells was significantly reduced at RNA and protein levels, and tumorigenic characteristics including cell proliferation, migration, and invasion were significantly reduced. In HERV-K env KO SKOV3 cells, the expression of the RB protein was significantly up-regulated and the cyclin B1 protein level was significantly reduced. In contrast, in HERV-K env KO OVCAR3 cells, the level of phospho-RB protein was significantly reduced, but other protein levels were not changed. CONCLUSION: The results of this study showed that HERV-K env gene KO affects cell proliferation, invasion, and migration of ovarian cells through RB and Cyclin B1 proteins, but the specific regulation pattern can differ by cell line.

Effects of thymosin ß4-derived peptides on migration and invasion of ovarian cancer cells.

BACKGROUND: Thymosin ß4 (Tß4) is a highly conserved actin binding protein associated with the metastatic potential of tumor cells by stimulating cell migration. The role of Tß4 and its derived fragment peptides in migration of ovarian cancer cells has not been studied. OBJECTIVE: To analyze the effects of Tß4 and its derived fragment peptides on ovarian cancer cell migration and invasion, we applied Tß4 and three Tß4-derived synthetic peptides to SKOV3 ovarian cancer cells. METHOD: The migration and invasion of SKOV3 cells treated with Tß4(1-43), Tß4(1-15), Tß4(12-26), Tß4(23-), and untreated control were analyzed by in vitro migration and invasion assay with transwell plate. Cell proliferation assay was conducted to identify the effect of Tß4 and its derived peptide on SKOV3 cell proliferation. The expression of Tß4 related proteins related with cell proliferation was analyzed by Western blot after treatment with Tß4 and its derived peptides. RESULTS: Cell migration and invasion were significantly increased in Tß4 peptide-treated SKOV3 cells compared with untreated control. All three Tß4-derived fragment peptides including those without an actin binding site significantly stimulated migration and invasion of SKOV3 cells. Tß4 and its derived peptide significantly stimulated SKOV3 cell proliferation and up-regulated the expression of RACK-1 protein. CONCLUSIONS: The Tß4 peptide and all of its derived fragment peptides including those without an actin binding motif stimulate migration and invasion of SKOV3 ovarian cancer cells. All peptides significantly increased RACK-1 expression and cell proliferation of SKOV3 cells. These results suggest that Tß4 stimulates migration and invasion of SKOV3 cells by stimulation of cell proliferation through up-regulation of RACK-1 protein.

Analysis of KAP1 expression patterns and human endogenous retrovirus Env proteins in ovarian cancer.

BACKGROUND: Human endogenous retroviruses (HERVs) constitute around 8% of the human genome and have important roles in human health and disease, including cancers. Previous studies showed that HERV envelope (Env) proteins are highly expressed in cancer tissues and co-related with cancer progression. KAP1 has been reported to play a key role in regulating retrotransposons, including HERV-K, through epigenetic silencing. OBJECTIVE: The relationship between KAP-1 and HERV Envs expressions was analyzed only in tumor cell lines and has not yet been studied in cancer tissues. In this study, we analyzed the expression patterns and relationship between KAP1 and HERV Env proteins in ovarian cancer tissues. METHOD: The expression patterns of KAP-1 and HERV Env proteins, including HERV-K and HERV-R, were analyzed in ovarian cancer tissue microarrays that contained 80 surgical specimens, including normal ovary and malignant ovarian cancers. RESULTS: The expression of HERV-R Env and KAP1 proteins is significantly higher in ovarian cancer compared with normal ovary tissues. However, the expression of HERV-K Env did not change significantly in cancer tissues. The expression patterns of HERV-K Env and HERV-R Env significantly increased in early stages of cancer and KAP1 expression was higher in certain stage and types of cancers. However, the expression of HERV-K Env, HERV-R Env, and KAP1 did not change in different age groups. The correlation between the expression of KAP1 and HERV-Env, including HERV-K and HERV-R, was not significantly correlated. CONCLUSIONS: The results of this study showed that there was no significant correlation between the expression of KAP1 and HERV Env proteins in ovarian cancer tissues, unlike studies with cell lines in vitro. These results suggest that the actual expression of HERV Env proteins in ovarian cancer tissues may be regulated through various complex factors as well as KAP1.

Correlation of long interspersed element-1 open reading frame 1 and c-Met proto-oncogene protein expression in ovarian cancer.

BACKGROUND: Hypomethylation of long interspersed nuclear element-1 (LINE-1) is closely related to certain cancers and concerns with aggressive tumor behavior. Previously, we reported LINE-1 open reading frame-1 (ORF1) protein level was significantly up-regulated in ovarian cancers compared with normal ovary. Hypomethylation of local LINE-1 sequence has been reported to reactivate MET proto-oncogene in colon cancers and hepatocellular carcinoma. However, the relationship between LINE-1 and c-MET expressions in ovarian cancer is not yet studied. METHOD: Here, we analyzed the expression patterns of LINE-1 ORF1 and c-Met protein in ovarian cancer tissue microarrays containing 208 surgical specimens including normal ovary and malignant ovarian cancers. RESULTS: The expressions of both LINE-1 ORF1 and c-Met protein were significantly increased in ovarian cancers and peaked in early stage of tumor. Other clinical data including age and tumor types were not significantly related with both proteins. Co-relationship between LINE-1 ORF1 and c-Met protein was significant (p = 0.03) but several patients show different expression patterns. CONCLUSIONS: These results propose that LINE-1 ORF1 significantly activates c-Met but not in all cases, suggesting other factors may be involved simultaneously.

Correlation of constitutive photomorphogenic 1 (COP1) and p27 tumor suppressor protein expression in ovarian cancer.

BACKGROUND: Constitutive photomorphogenic 1 (COP1) is an E3 ubiquitin ligase that regulates important target proteins for cell growth including p27. The tumor suppressor p27 negatively regulates the cell cycle by inhibiting cyclin-dependent kinase. COP1 negatively regulates p27 stability by mediating its nuclear export and degradation. OBJECTIVE: Even if COP1 and p27 are tightly related and have significant roles in tumor progression, the expression patterns and relationship of both proteins in cancer have not yet been studied. METHOD: We analyzed the expression patterns and relationship between COP1 and p27 using an ovarian cancer tissue microarray by dual immunofluorescence analysis. RESULTS: The expression levels of COP1 and p27 proteins were not significantly different between ovarian cancer tissue and normal control tissue. Other clinical data including age, tumor type, tumor grade, and stage were not significantly related to expression of the two proteins. The co-relationship between COP1 and p27 proteins was significantly high (Pearson correlation coefficient 0.79, p = 8.65 × 10-22). CONCLUSIONS: Our results demonstrate that while the expression levels of COP1 and p27 are highly correlated, they are not significantly related to cancer progression in ovarian cancer.

Do Endometrial Movements Affect The Achievement of Pregnancy during Intrauterine Insemination?

BACKGROUND: This study was aimed to assess the effect of endometrial movements on pregnancy achievement in intrauterine insemination (IUI) cycles. MATERIALS AND METHODS: The population of this observational study was composed of unexplained infertility couples undergoing first-time IUI with clomiphene citrate between September 2010 and October 2011. Not only endometrial movements, but also thickness, volume, pattern, and echogenic change of endometrium were analyzed prospectively in prediction of pregnancy. RESULTS: The total number of 241 cycles of IUI with 49 intrauterine pregnancies (20.3%) was analyzed. Pregnancy was not related to endometrial thickness and endometrial volume, but significantly related to endometrial movements associated with the number of contraction, strong movement, cervicofundal direction, and hyperechoic change (p<0.05). Pregnant group showed higher cervicofundal movement rate (89.8 vs. 75.5%). CONCLUSION: For IUI cycles stimulated by clomiphene citrate in unexplained infertility women, endometrial movements on the day of IUI could be a predictor of pregnancy.

Absolute monocyte and lymphocyte count prognostic score for patients with gastric cancer.

AIM: To measure the prognostic significance of absolute monocyte count/absolute lymphocyte count prognostic score (AMLPS) in patients with gastric cancer. METHODS: We retrospectively examined the combination of absolute monocyte count (AMC) and absolute lymphocyte count (ALC) as prognostic variables in a cohort of 299 gastric cancer patients who underwent surgical resection between 2006 and 2013 and were followed at a single institution. Both AMC and ALC were dichotomized into two groups using cut-off points determined by receiving operator characteristic curve analysis. An AMLPS was generated, which stratified patients into three risk groups: low risk (both low AMC and high ALC), intermediate risk (either high AMC or low ALC), and high risk (both high AMC and low ALC). The primary objective of the study was to validate the impact of AMLPS on both disease-free survival (DFS) and overall survival (OS), and the second objective was to assess the AMLPS as an independent prognostic factor for survival in comparison with known prognostic factors. RESULTS: Using data from the entire cohort, the most discriminative cut-off values of AMC and ALC selected on the receiver operating characteristic curve were 672.4/µL and 1734/µL for DFS and OS. AMLPS risk groups included 158 (52.8%) patients in the low-risk, 128 (42.8%) in the intermediate-risk, and 13 (4.3%) in the high-risk group. With a median follow-up of 37.2 mo (range: 1.7-91.4 mo), five-year DFS rates in the low-, intermediate-, and high-risk groups were 83.4%, 78.7%, and 19.8%, respectively. And five-year OS rates in the low-, intermediate-, and high-risk groups were 89.3%, 81.1%, and 14.4%, respectively. On multivariate analysis performed with patient- and tumor-related factors, we identified AMLPS, age, and pathologic tumor-node-metastasis stage as the most valuable prognostic factors impacting DFS and OS. CONCLUSION: AMLPS identified patients with a poor DFS and OS, and it was independent of age, pathologic stage, and various inflammatory markers.

Changes in bone density after cancer treatment in patients with cervical and endometrial cancer.

OBJECTIVE: This study aimed to evaluate the impact of cancer treatment on bone mineral density (BMD) in the lumbar spine (LS) and femur in the postmenopausal women with cervical or endometrial cancer without bone metastasis compared to normal control postmenopausal women. METHODS: We retrospectively evaluated the BMD data in the LS, femur neck (FN) and trochanter (FT) by dual-energy X-ray absorptiometry and laboratory data of bone turnover markers at baseline and after one year in 130 patients with cervical cancer, 68 patients with endometrial cancer, and 225 healthy controls. RESULTS: There were no significant differences in the T-scores of basal BMD in LS and femur between patients with endometrial cancer and controls, and only T-score of basal BMD at the fourth lumbar vertebra (L4) was significantly lower in patients with cervical cancer compared to controls. One year later, T-scores of BMD at all LS sites and FN in patients with cervical cancer and T-scores of BMD at L3, L4, FN, and FT in those with endometrial cancer after cancer treatment were significantly lower compared to controls. Lower proportions of normal BMD at all skeletal sites except L2 in patients with endometrial cancer and those at L1, L4, and FN in patients with cervical cancer were observed compared to controls after cancer treatment. CONCLUSIONS: Our results suggest that cancer treatment increase bone loss in postmenopausal women with cervical and endometrial cancer.

Effects of menopausal hormone therapy on uterine myoma in menopausal women.

OBJECTIVES: The aim of the present study is to evaluate the long term effects of estrogen-progestogen therapy (EPT) on uterine myomas volume in postmenopausal women. METHODS: We performed a retrospective analysis on postmenopausal women with asymptomatic uterine myoma during the period between April, 2008 and September, 2012. Postmenopause was defined as amenorrhea for longer than a year or serum follicle stimulating hormone levels higher than 40 IU/L. The volume of the myoma was assessed by transvaginal ultrasonography for every 6 months after administration of EPT. RESULTS: Thirty-eight women were included in the study, with 32 in the EPT group and 6 in the control group. Overall, uterine myoma volume (mean ± standard deviation, cm(3)) in the EPT group was 19.5 ± 24.6 at baseline, and those at 6 and 12 months were 24.7 ± 35.1 and 28.5 ± 56.4, respectively. Myoma volume did not change significantly with EPT, and these changes were not significantly different from the control group. Myoma volume changes were not significantly different in the subgroups according to the route of estrogen administrations and the method of progestogen administrations. Clinically significant volume increases during one year of EPT was noted in 28.1% (9/32), however, only one showed transient increases. CONCLUSION: Our results suggest that treating postmenopausal woman with EPT on a long-term basis does not increase the volume of uterine myomas.