Apicidin, a novel histone deacetylase inhibitor, has profound anti-growth activity in human endometrial and ovarian cancer cells

Histone deacetylase inhibitors (HDACIs) can inhibit proliferation, induce cell cycle arrest and stimulate apoptosis of cancer cells. Our purpose was to investigate the antiproliferative effects of a novel HDACI, apicidin, on the Ishikawa endometrial cancer cell line, the SK-OV-3 ovarian cancer cell line and normal human endometrial epithelial cells. Endometrial and ovarian cancer cells were treated with various concentrations of apicidin, and the effects on cell growth, cell cycle, apoptosis and related measurements were investigated. MTT assays showed that all endometrial and ovarian cancer cell lines were sensitive to the growth inhibitory effect of apicidin, although normal endometrial epithelial cells were viable after the treatment with the same doses of apicidin that induced the growth inhibition of endometrial and ovarian cancer cells. Cell cycle analysis indicated that their exposure to apicidin decreased the proportion of cells in S-phase and increased the proportion in G0/G1 and/or G2/M phases of the cell cycle. Induction of apoptosis was confirmed by Annexin V staining of externalized phosphatidylserine and loss of the transmembrane potential of mitochondria. This induction occurred in concert with the altered expression of p21WAF1, p27KIP1, p16, cyclin A, and E-cadherin. Furthermore, apicidin treatment of these cell lines increased acetylation of H3 and H4 histone tails. These results suggest that apicidin exhibits the antiproliferative effects through selective induction of genes related to cell growth, malignant phenotype, and apoptosis. The findings raise the possibility that apicidin may prove particularly effective in the treatment of endometrial and ovarian cancers.     

Bufalin induces growth inhibition, cell cycle arrest and apoptosis in human endometrial and ovarian cancer cells

Bufalin is a traditional Chinese medicine and it induces apoptosis in certain human tumor cell lines. We investigated the effect of bufalin on three endometrial cancer cell lines, two ovarian cancer cell lines, and on normal human endometrial epithelial cells. Endometrial and ovarian cancer cells were treated with various concentrations of bufalin, and its effect on cell growth, cell cycle, apoptosis, and related measurements was investigated. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that all endometrial and ovarian cancer cell lines were sensitive to the growth-inhibitory effect of bufalin, although normal endometrial epithelial cells were viable after treatment with the same doses of bufalin that induced growth inhibition in endometrial and ovarian cancer cells. Cell cycle analysis indicated that their exposure to bufalin decreased the proportion of cells in the S-phase and increased the proportion in the G0/G1 phases of the cell cycle. Induction of apoptosis was confirmed by annexin V staining of externalized phosphatidylserine and loss of the transmembrane potential of mitochondria. This induction occurred in concert with the altered expression of genes related to cell cycle and apoptosis. These results suggest that bufalin may become a useful adjuvant therapy for endometrial and ovarian cancers with minimal side effects.     

Selective cell cycle arrest and induction of apoptosis in human prostate cancer cells by a polyphenol-rich extract of Solanum nigrum

Progression of prostate cancer is associated with escape of tumor cells from cell cycle arrest and apoptosis. Agents capable of selectively eliminating cancer cells by cell cycle arrest and/or induction of apoptosis offer a highly desirable approach. Here we demonstrate that a polyphenolic extract derived from ripe berries of Solanum nigrum (SN) differentially causes cell cycle arrest and apoptosis in various human prostate cancer cells without affecting normal prostate epithelial cells. Virally transformed normal human prostate epithelial PZ-HPV-7 cells and their cancer counterpart CA-HPV-10 cells, were used to evaluate the growth-inhibitory effects of the SN extract. SN treatment (5-20 μg/ml) of PZ-HPV-7 cells resulted in growth inhibitory responses of low magnitude. In sharp contrast, SN treatment of CA-HPV-10 cells increased cytotoxicity, decreased cell viability and induced apoptosis. Similar results were noted in the human prostate cancer LNCaP, 22Rv1, DU145 and PC-3 cell lines, where significant reductions in cell viability and induction of apoptosis was observed in all these cells, an effect independent of disease stage and androgen association. Cell cycle analysis revealed that SN treatment (5-20 μg/ml) resulted in a dose-dependent G2/M phase arrest and subG1 accumulation in the CA-HPV-10 but not in the PZ-HPV-7 cell line. Our results, for the first time, demonstrate that the SN extract is capable of selectively inhibiting cellular proliferation and accelerating apoptotic events in prostate cancer cells. SN may be developed as a promising therapeutic and/or preventive agent against prostate cancer.     

Diallyl trisulfide selectively causes Bax- and Bak-mediated apoptosis in human lung cancer cells

Garlic-derived organosulfur compounds (OSCs) are highly effective in affording protection against chemically induced pulmonary carcinogenesis in animal models. We now demonstrate that garlic constituent diallyl trisulfide (DATS) suppresses viability of cultured human lung cancer cell lines H358 (anon-small cell lung cancer cell line) and H460 (a large cell lung cancer cell line) by causing G2-M phase cell cycle arrest and apoptotic cell death. On the other hand, a normal human bronchial epithelial cell line BEAS-2B was significantly more resistant to growth inhibition and apoptosis induction by DATS compared with lung cancer cells. We also found that even a subtle change in the OSC structure could have a significant impact on its biological activity. For example, DATS was significantly more effective than either diallyl sulfide or diallyl disulfide against proliferation of lung cancer cells. The DATS-mediated G2-M phase cell cycle arrest was explained by down-regulation of cyclin-dependent kinase 1 (Cdk1) and cell division cycle 25C protein expression leading to accumulation of Tyr15 phosphorylated (inactive) Cdk1. The DATS-induced apoptosis correlated with induction of pro-apoptotic proteins Bax, Bak and BID, and a decrease in the expression of anti-apoptotic proteins Bcl-2 and Bcl-xL in lung cancer cells but not in BEAS-2B. Knockdown of Bax and Bak proteins conferred significant protection against DATS-induced apoptotic cytoplasmic histone-associated DNA fragmentation. On the other hand, BID protein was dispensable for DATS-induced apoptosis. In conclusion, the present study indicates that Bax and Bak proteins are critical targets of DATS-induced apoptosis in human lung cancer cells.     

CDKN3 knockdown reduces cell proliferation,invasion and promotes apoptosis in human ovarian cancer

Cyclin-dependent kinase inhibitor 3 (CDKN3) has been reported to promote tumor genesis. The aim of this study is to investigate the possible mechanisms of silence of CDKN3 exerting the suppressive role on epithelial ovarian cancer (EOC). To study the potential function of CDKN3 enrolled in the regulation of ovarian tumor, we monitored the EOC cells SKOV3 and HO8910 behaviors including proliferation, cell cycle, apoptosis and invasion. First, we found that CDKN3 was frequently over-expressed in EOC. Functional studies showed that silence of CDKN3 inhibited cancer cell proliferation by promoting cell cycle progression in G1 phase, decreased cell invasion and promoted EOC cells apoptosis. Western blot analysis of CDKN3-silence cells revealed down-regulation of DNA-replication and cell cycle related proteins. And, a significant correlation level of CDKN3 was observed which has been demonstrated to be a novel oncogene. These findings indicated that CDKN3 might serve as a useful potential target for treatment of ovarian cancer.     

Histone deacetylase inhibitors induce growth inhibition, cell cycle arrest and apoptosis in human choriocarcinoma cells

We investigated the effect of five histone deacetylase inhibitors (HDACIs) on the choriocarcinoma cell line, BeWo. BeWo cells were treated with various concentrations of five HDACIs, and their effects on cell growth, cell cycle, apoptosis, and related measurements were investigated. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assays showed that the BeWo choriocarcinoma cell line was sensitive to the growth inhibitory effect of five HDACIs. Cell cycle analysis indicated that exposure to HDACIs decreased the proportion of cells in the S-phase and increased the proportion in the G0/G1 phases of the cell cycle. Induction of apoptosis was confirmed by annexin V staining of externalized phosphatidylserine and loss of the transmembrane potential of mitochondria. This induction occurred in concert with altered expression of genes related to cell growth, malignant phenotype, and apoptosis. Furthermore, HDACI treatment of this cell line increased acetylation of H3 and H4 histone tails. These results raise the possibility that HDACIs may prove particularly effective in the treatment of choriocarcinoma.     

LncRNA MEG3 impacts proliferation,invasion, and migration of ovarian cancer cells through regulating PTEN

Objective and design

We investigated the expressions of lncRNA MEG3 and PTEN in ovarian cancer tissues and their effects on cell proliferation, cycle and apoptosis of ovarian cancer.

Methods

Expression levels of MEG3 in ovarian cancer cell lines and normal ovarian cell lines were detected by qRT-PCR. Cell viability was detected by MTT assay. Cell apoptosis and cell cycle distribution were measured by flow cytometry. Cell invasion capability was tested by transwell assay. Cell migration capacity was tested by wound healing. The xenograft model was constructed to explore the effect of lncRNA MEG3 on ovarian cancer in vivo.

Result

Compared with normal ovarian cells, expression levels of MEG3 and PTEN were relatively lower in ovarian cancer cells. There was a positive correlation between the expression of PTEN and the expression of MEG3. Enhanced expression level of PTEN suppressed SKOV3 cell proliferation, increased cell apoptosis rate, and decreased cell invasion and migration.

Conclusion

LncRNA MEG3 and PTEN were down-regulated in ovarian cancer cells. LncRNA MEG3 regulated the downstream gene PTEN in ovarian cancer cells to prohibit cell proliferation, promote apoptosis and block cell cycle progression.

     

TROP-1/Ep-CAM and CD24 are potential candidates for ovarian cancer therapy

To clarify the possible roles of epithelial cell adhesion molecule (TROP-1/Ep-CAM) and CD24 molecule (CD24) in ovarian tumorigenesis, and explore the possible mechanism underlying this disease. Recombinant eukaryotic expression vectors pCIneo-TROP-1/Ep-CAM and pCIneo-CD24 were transfected into human normal ovarian surface epithelia cell line IOSE-80 respectively, with IOSE-80 cells transfected with the empty vector pCIneo as control. MRNA and protein expression of TROP-1/Ep-CAM and CD24 were detected by RT-PCR and Western blotting, respectively. Cell migration was assayed by trans-well inserts; cell proliferation and adhesion were analyzed by CCK-8 Cell Counting kit; cell cycle and cell apoptosis analysis were performed by flow cytometer. The expressions of TROP-1/Ep-CAM and CD24 were obviously up-regulated in TROP-1/Ep-CAM group and CD24 group compared to that in control group (P < 0.01). Cells of TROP-1/Ep-CAM group and CD24 group was significantly promoted migratory and proliferation abilities, but inhibited cell apoptosis and adhesive than that of control group (P < 0.05). Besides, the number of the cells in G1 and G2 stages was significantly lower in two disease groups than that in control group (P < 0.05). TROP-1/Ep-CAM and CD24 may play key roles in the progression of ovarian cancer through promoting migration, proliferation, inhibiting cell apoptosis and adhesion, and disturbing cell cycle. They may be used as specific therapeutic targets in the treatment of ovarian cancer. However, further experiments are still needed to confirm our results.     

Berberine inhibited the growth of thyroid cancer cell lines 8505C and TPC1

Purpose

Thyroid cancer is the most common malignancy in Korean females and can be treated with good prognosis. However, drugs to treat aggressive types of thyroid cancer such as poorly differentiated or anaplastic thyroid cancer have not yet been established. To that end, we analyzed the effects of berberine on human thyroid cancer cell lines to determine whether this compound is useful in the treatment of aggressive thyroid cancer.

Materials and Methods

The two thyroid cancer cell lines 8505C and TPC1, under adherent culture conditions, were treated with berberine and analyzed for changes in cell growth, cell cycle duration, and degree of apoptosis.

Results

Following berberine treatment, both cell lines showed a dose-dependent reduction in growth rate. 8505C cells showed significantly increased levels of apoptosis following berberine treatment, whereas TPC1 cells showed cell cycle arrest at the G0/G1 phase. Immunobloting of p-27 expression following berberine treatment showed that berberine induced a little up-regulation of p-27 in 8505c cells but relatively high up-regulation of p-27 in TPC1 cells.

Conclusion

These results suggest that berberine treatment of thyroid cancer can inhibit proliferation through apoptosis and/or cell cycle arrest. Thus, berberine may be a novel anticancer drug for the treatment of poorly differentiated or anaplastic thyroid cancer.     

miR-132 靶向调控Ezrin 抑制卵巢癌细胞增殖、促进凋亡的实验研究

目的:探讨微小核糖核酸分子(miRNA)-132 在卵巢癌中生物学作用和作用靶点。方法:收集22 例卵巢癌及癌旁非肿瘤组织标本,RT-PCR 检测miR-132 表达量;RT-PCR 检测人正常卵巢上皮细胞和卵巢癌细胞系中miR-132 表达量;选择miR-132 表达量最高或最低的卵巢癌细胞株,分别转染阴性对照质粒(NC)和miR-132 mimic 质粒,RT-PCR 检测转染后miR-132 表达量;CCK-8 法检测细胞增殖,流式细胞仪检测细胞凋亡,Western blot 检测Ezrin 蛋白表达。结果:卵巢癌组织中miR-132 表达量显著低于癌旁非肿瘤组织,而卵巢癌细胞系中miR-132 表达量显著低于正常卵巢上皮细胞,差异均有统计学意义(P<0.05);选择卵巢癌细胞株中miR-132 表达量最低卵巢癌SKOV3 细胞株进行基因转染,与转染阴性对照质粒相比,转染miR-132 mimic 质粒后miR-132 表达量显著上升,细胞增殖显著降低,细胞凋亡显著增加,差异均有统计学意义(P<0.05);Western blot 结果显示,上调miR-132 表达后,卵巢癌SKOV3 细胞株中Ezrin 蛋白表达显著上升(P<0.05)。结论:在卵巢癌中,miR-132 可能作为一种抑癌基因通过靶向调控Ezrin 抑制卵巢癌细胞增殖、促进凋亡。     

PDK1对肺癌A549细胞生物学行为的影响

目的:探讨3-磷酸肌醇依赖性蛋白激酶1(PDK1)对肺癌细胞株A549生物学特性的影响及其潜在的作用机制。方法:采用Western blot和real-time PCR检测肺正常上皮细胞BEAS-2B和肺癌细胞(H460、SPCA1和A549)中PDK1的表达水平。利用RNA干扰技术下调肺癌A549细胞中PDK1的表达,然后分别采用CCK-8法和流式细胞术检测细胞活力及凋亡的变化;Western blot检测增殖及周期相关蛋白的表达和Akt/Fox O1信号通路的活性。最后通过Akt信号通路特异性激动剂胰岛素样生长因子1(insulin-like growth factor-1,IGF-1)进一步验证PDK1和Akt/Fox O1信号通路的相互作用。结果:相较于肺正常上皮细胞BEAS-2B,肺癌细胞中的PDK1均呈高表达(P0.05)。干扰A549细胞中PDK1的表达后,细胞活力显著降低,周期进程缓慢,而细胞凋亡显著增加。Western blot实验结果显示,干扰PDK1后,细胞中cyclin D1、CDK4、p-Rb、Bcl-2、p-Akt及胞浆中p-Fox O1的含量显著下降,P27、cleaved caspase-3及核内Fox O1的蛋白水平显著升高(P0.05)。预先给予Akt激动剂IGF-1可部分逆转干扰PDK1对Akt/Fox O1信号通路的影响,并增加A549细胞的活力(P0.05)。结论:干扰人肺癌细胞株A549的PDK1可通过抑制Akt/Fox O1信号通路而调控周期及凋亡相关因子的表达,发挥生长抑制及凋亡促进作用,提示PDK1可作为肺癌的潜在诊疗靶点。     

Effect of bone morphogenetic protein-2 on proliferation and apoptosis of gastric cancer cells

Objective: To investigate the effects of bone morphogenetic protein-2 (BMP-2) on the proliferation, differentiation and apoptosis of normal human gastric mucosal cells and gastric cancer cells.Methods: Poorly differentiated gastric cancer BGC823 cells, moderately differentiated gastric cancer cells and normal human gastric mucosal epithelial GES-1 cells were independently treated with recombinant human BMP-2 or its inhibitor Noggin. MTT assay was performed to detect the proliferation, flow cytometry done to measure the cell cycle and apoptosis and immunohistochemistry carried out to determine the expression of cyclin-dependent kinase 4 (CDK4).Results: BMP-2 exerted inhibitory effect on the growth of all types of cells and the inhibition become more evident with the increase of BMP-2 dose. After treatment with 200 ng/ml BMP-2, cancer cells arrested in G1 phase and those in S phase reduced. Gastric cancer cells had higher CDK4 expression than GES-1 cells. BMP-2 decreased CDK-4 expression in cancer cells but had no influence in GES-1 cells. Noggin conferred promotive effect on the growth of 3 types of cells. In 2 types of cancer cells, treatment with 2000 ng/ml Noggin significantly increased the proportion of cells in S phase but reduced that in G1 phase. However, Noggin did not affect the cell cycle of GES-1 cells. The CDK4 expression was markedly increased in 2 types of cancer cells but that of GES-1 remained unchanged after treatment with 2000 ng/ml Noggin.Conclusions: BMP-2 may inhibit the proliferation of both normal and malignant gastric epithelial cells, down-regulate CDK4 expression in gastric cancer cells and arrest gastric cancer cells in G1-phase in cell cycle. Through antagonizing BMP-2, Noggin, may accelerate the proliferation of gastric cancer cells. Thus, the abnormality of BMP signaling pathway may play an important role in the pathogenesis of gastric cancer.     

槲皮素对人卵巢癌SKOV-3细胞增殖的影响

 目的：探讨槲皮素对人卵巢癌SKOV-3细胞增殖抑制和凋亡的影响,为卵巢癌临床治疗提供依据。方法：不同浓度槲皮素处理卵巢癌SKOV-3细胞后,采用MTT实验检测细胞增殖抑制作用并计算抑制率,细胞免疫化学染色法鉴定细胞凋亡,流式细胞术检测细胞周期及细胞凋亡。结果：槲皮素能够抑制SKOV-3细胞的增殖,且呈时间和剂量依赖性,免疫荧光显示槲皮素对SKOV-3细胞具有诱导凋亡作用,流式细胞术显示SKOV-3细胞被阻滞在S期, G2/M期细胞比例降低,凋亡率上升。结论：槲皮素在体外能够抑制卵巢癌SKOV-3细胞的增殖,阻止细胞由S期向G2期移行,促进其凋亡。     

miR-211 对上皮性卵巢癌细胞HO8910 增殖及细胞周期相关蛋白的影响

目的:探讨miR-211 与上皮性卵巢癌发生的关系,及其对卵巢癌细胞增殖的影响。方法:对30 例上皮性卵巢癌组织标本及卵巢癌细胞系HO8910 中miR-211、Cyclin D1 和CDK6 表达情况进行研究,同时选取30 例非卵巢癌患者组织标本及正常卵巢上皮细胞株IOSE80 作为对照,并分析上皮性卵巢癌组织及卵巢癌细胞系中miR-211、Cyclin D1、CDK6 表达情况及表达相关性;miR-211 对卵巢癌细胞增殖,以及对Cyclin D1 和CDK6 表达的影响。结果:卵巢癌组织miR-211 相对表达水平显著低于正常组织(P<0.05),卵巢癌细胞中miR-211 相对表达水平显著低于正常卵巢上皮细胞(P<0.05);在上皮性卵巢癌细胞系HO8910 中,第3 天和第4 天miR-211 组细胞数显著低于miR-Ctrl (P<0.05);上皮性卵巢癌组织中Cyclin D1、CDK6相对表达水平显著高于正常卵巢上皮组织(P<0.05);上皮性卵巢癌细胞系中miR-211 显著抑制Cyclin D1 和CDK6 的表达;在卵巢癌组织中,Spearman 相关性分析结果显示miR-211 和Cyclin D1 和CDK6 相对表达水平呈负相关(r =-0.583,P =0.010)。结论:miR-211 可抑制卵巢癌细胞增殖,并抑制周期相关蛋白Cyclin D1 和CDK6 的表达,miR-211 与周期相关蛋白Cyclin D1 和CDK6 在卵巢癌发生中可能存在调控关系。     

Glycodelin blocks progression to S phase and inhibits cell growth: a possible progesterone-induced regulator for endometrial epithelial cell growth

Prolonged exposure to unopposed estrogen in the absence of progesterone gives rise to endometrial hyperplasia and carcinoma. Post-ovulatory progesterone is necessary for the proper growth and differentiation of endometrial epithelial cells (EECs). Progesterone exposure induces the endometrial production of numerous bioactive substances, one of which is the glycoprotein, glycodelin (Gd). We investigated the role of Gd in cell cycle progression and cell growth to better understand how Gd affects EEC behavior and endometrial cancer pathogenesis. Ishikawa cells, a well-differentiated human endometrial epithelial cancer cell line, were transfected with expression plasmids encoding enhanced green fluorescent protein (EGFP) or EGFP-fused Gd (EGFP-Gd). They were then subjected to a cell proliferation assay, flow cytometry cell cycle analysis and RT-PCR analysis of cyclin-dependent kinase inhibitors (CDKIs) including p21, p27 and p16. Overexpression of EGFP-Gd resulted in a reduction of cell proliferation activity, an accumulation of G1-phase cells and up-regulation of p21, p27 and p16 mRNAs. Furthermore, progesterone-induced inhibition of Ishikawa cell growth was partially attenuated by Gd knockdown using siRNA. These results indicate that Gd causes inhibition of G1/S progression together with up-regulation of CDKIs thereby reducing cell growth. Thus, progesterone-induced expression of Gd may, at least in part, contribute to the suppression of endometrial epithelial growth observed during the secretory phase.     

MicroRNA-101 inhibits growth and metastasis of human ovarian cancer cells by targeting PI3K/AKT

IntroductionOvarian cancer is the most frequent cause of gynecological cancer related mortality in woman. This study was designed to investigate the role and therapeutic potential of miRNA-101 in ovarian cancer.Material and methodsExpression analysis was carried out by real-time quantitative polymerase chain reaction. Transfections were performed with the help of Lipofectamine 2000 reagent. AO/EB and annexin V/PI staining was used to detect apoptosis and flow cytometry was used for cell cycle analysis. Western blotting was employed for cell cycle analysis.ResultsIt was found that miRNA-101 was significantly down-regulated in ovarian cancer cells. The over-expression of miRNA-101 causes a significant decrease in the viability of ovarian cancer cells via the initiation of apoptosis and sub-G1 arrest of OVACAR-3 cells. It was indicated that PTEN was the potential target of miRNA-101 in OVACAR-3 cells. There was 4.5-fold up-regulation of PTEN expression in ovarian cancer cell lines and the over-expression of miRNA-101 in OVACAR-3 cells resulted in the down-regulation of PTEN expression. The inhibition of PTEN in the OVACAR-3 cells arrested the proliferation of these cells. The over-expression of miRNA-101 causes significant down-regulation in PI3K and AKT expression of OVACAR-3 cells.ConclusionsIt can be concluded that miRNA-101 acts as a tumor suppressor which may be beneficial in the treatment of ovarian cancer.     

Integrin-linked kinase expression increases with ovarian tumour grade and is sustained by peritoneal tumour fluid

Integrin-linked kinase (ILK) is a serine threonine kinase, overexpression of which promotes tumour growth and invasion through deregulation of the cell cycle. This study demonstrates the relative expression of ILK in normal, benign, low-grade, and high-grade (borderline, grade I/II, and grade III) ovarian tumours of serous, mucinous, endometrioid, and clear cell types in order to assess its potential as a marker for epithelial ovarian cancer progression. Seventy-three specimens including ten normal, ten benign, 14 borderline, 17 grade I/II, and 22 grade III were evaluated by immunohistochemistry. Immunoreactive ILK was not detectable in normal ovarian surface epithelium. All 53 carcinomas studied were positive and the staining intensity correlated significantly with the grade of the tumour. Ovarian cancer cell lines had high expression of ILK, while immortalized normal ovarian surface epithelial cell lines (HOSE) showed low basal expression of ILK by western blotting. Peritoneal tumour fluid (PTF) upregulated ILK expression in ovarian cancer cell lines but had no effect on HOSE cells. PTF-induced up-regulation of ILK expression in ovarian cancer cell lines correlated with the activation of the downstream protein kinase B (PKB/Akt) pathway. Collectively, these data demonstrate that ILK expression increases with ovarian cancer progression and that soluble factors in PTF mediate sustained overexpression of ILK in ovarian cancer cells. Suppression of ILK expression may therefore represent a novel and an efficient mechanism for controlling ovarian tumour growth.     

LncRNA MEG3 impacts proliferation,invasion, and migration of ovarian cancer cells through regulating <Emphasis Type="Italic">PTEN</Emphasis>

Objective and design

We investigated the expressions of lncRNA MEG3 and PTEN in ovarian cancer tissues and their effects on cell proliferation, cycle and apoptosis of ovarian cancer.

Methods

Expression levels of MEG3 in ovarian cancer cell lines and normal ovarian cell lines were detected by qRT-PCR. Cell viability was detected by MTT assay. Cell apoptosis and cell cycle distribution were measured by flow cytometry. Cell invasion capability was tested by transwell assay. Cell migration capacity was tested by wound healing. The xenograft model was constructed to explore the effect of lncRNA MEG3 on ovarian cancer in vivo.

Result

Compared with normal ovarian cells, expression levels of MEG3 and PTEN were relatively lower in ovarian cancer cells. There was a positive correlation between the expression of PTEN and the expression of MEG3. Enhanced expression level of PTEN suppressed SKOV3 cell proliferation, increased cell apoptosis rate, and decreased cell invasion and migration.

Conclusion

LncRNA MEG3 and PTEN were down-regulated in ovarian cancer cells. LncRNA MEG3 regulated the downstream gene PTEN in ovarian cancer cells to prohibit cell proliferation, promote apoptosis and block cell cycle progression.

     

Inhibitory effects of bisphosphonates on the proliferation of human ovarian cancer cell lines and the mechanism

Bisphosphonates are now well established as successful agents for the prevention and treatment of postmenopausal osteoporosis and corticosteroid-induced bone loss. Bisphosphonates have also recently become important in the management of cancer-induced bone disease, and they now have a widely recognized role for patients with multiple myeloma and bone metastases secondary to breast cancer and prostate cancer. Recent studies suggest that, besides the strong antiosteoclastic activity, the efficacy of such compounds in the oncological setting could also be due to direct anti-tumor effect. However, the effect of bisphosphonates to ovarian and endometrial cancers has not been elucidated. Thus, we examined the direct effect of bisphosphonates on the various ovarian cancer cell lines. Except for etidronate, all of bisphosphonates examined had the direct inhibitory effects on proliferation of all ovarian cancer cell lines used. Especially, pamidronate had the most marked inhibitory effect and inhibited dose-dependently the proliferation of ovarian cancer cell lines. KFr 13 cells among ovarian cancer cell lines used was the most sensitive to pamidronate and the caspase 3 activity was markedly stimulated by treatment with pamidronate, suggesting induction of apoptosis.