ObjectiveTo explore expression of Mdm2 in the estrogen receptor α (ERα)-positive breast cancer tissues and fibroadenoma of breast tissues, and to explore the effect of MDM2-siRNA on cell proliferation, colony formation, and apoptosis for MCF-7 cells. Methods① Seventy eight ERα-positive breast cancer patients identified by histopathological examination, who underwent surgery in our hospital from June 2012 to October 2015, as well as 10 fibroadenoma of breast patients underwent surgery in the same period, were collected retrospectively to determine the expression of Mdm2, then explore the relationship between the expression of Mdm2 and clinical pathological characteristics of ERα-positive breast cancer patients. ② MCF-7 cells were divided to MDM2-siRNA group (added with MDM2-siRNA), negative control group (added with negative siRNA), and blank control group (added without any reagent). Expression of Mdm2, cell proliferation rate, number of colony formation, and apoptosis rate were determined in the MCF-7 cells of 3 groups. Results① No one of fibroadenoma of breast patients was found positive expression of Mdm2 (0/10), and 38 of 78 ERα-positive breast cancer patients were found the positive expression of Mdm2 (48.7%), which is higher than that of fibroadenoma of breast tissues (χ2=12.357, P=0.000). In ERα-positive breast cancer patients, expression of Mdm2 was related with TNM staging and number of metastasic lymph node (P < 0.050), the positive expression rate of Mdm2 was higher in patients with later TNM staging or more metastasic lymph node. ② Cell proliferation rates on 2, 3, and 4 days after transfection, expression level of Mdm2, and number of colony formation were all lower (P < 0.050), but the apoptosis rate was higher in MDM2-siRNA group (P < 0.050), comparing with negative control group and blank control group. But there was no significant difference between negative control group and blank control group on aforementioned indexes (P > 0.050). ConclusionMdm2 is a diagnostic marker in ERα-positive breast cancer patients, and treatment targeting it might has a certain therapeutic value.
Objective To explore the role of estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) in estrogen-induced proliferation of endometrial cancer, and explore whether metformin inhibits the proliferation of endometrial cancer cells through ERα and ERβ. Methods Stable transfected Ishikawa cells were constructed by lentivirus. The effects of down-regulated ERα and ERβ on estrogen-induced Ishikawa cell proliferation were detected by methyl thiazolyl tetrazolium assay. The effects of down-regulated ERα and ERβ on estrogen-induced Ishikawa cell cycle were detected by flow cytometry. In addition, quantitative real-time polymerase chain reaction and Western blotting assays were used to detect changes in the expression of cyclinD1 and P21 involved in cell cycle regulation. The effects of down-regulated ERα and ERβ on estrogen-induced Ishikawa cell proliferation were observed by adding metformin to estrogen treatment. Results Down-regulation of ERα inhibited the proliferation and cell cycle of Ishikawa cells (P<0.05). Down-regulation of ERα also inhibited the expression of cyclinD1 and promoted the expression of P21 (P<0.05). Down-regulation of ERα counteracted the effect of estrogen-induced cell proliferation, cell cycle, and the expression changes of cyclinD1 and P21 (P<0.05). Down-regulation of ERβ promoted the proliferation and cell cycle of Ishikawa cells (P<0.05). Down-regulation of ERβ also promoted the expression of cyclinD1 and inhibited the expression of P21 (P<0.05). Down-regulation of ERβ enhanced the effect of estrogen-induced cell proliferation, cell cycle, and the expression changes of cyclinD1 and P21 (P<0.05). Metformin inhibited the proliferation of estrogen-induced Ishikawa cells (P<0.05), while in the down-regulated ERα Ishikawa cells or down-regulated ERβ Ishikawa cells, the inhibition of metformin on Ishikawa cells disappeared (P<0.05). Conclusions ERα may promote estrogen-induced proliferation of endometrial cancer cells, while ERβ may inhibit estrogen-induced proliferation of endometrial cancer cells. In addition, ERα and ERβ may also mediate the inhibitory effect of metformin on endometrial cancer cells.
ObjectiveTo explore the associations between estrogen receptor α (ESR1) gene intron 1 PvuⅡ (−397 T/C, rs2334693), XbaⅠ (−351 A/G, rs9340799) polymorphisms and premature ovarian failure (POF).MethodsLiterature published before February 2021 were retrieved in PubMed, Web of Science, China National Knowledge Infrastructure, Wanfang, and CQVIP databases, according to the inclusion and exclusion criteria developed before. Odds ratio (OR) and 95% confidence interval (CI) were used for data analysis, the Q test and I2 statistic were used for heterogeneity analysis. Random-effect model or fixed-effect model was used according to I2 value. All analyses were performed by RevMan 5.3 software.ResultsSix case-control studies were included in this meta-analysis. For the associations between ESR1 gene intron 1 PvuⅡ polymorphisms and POF, there was no statistical difference in TT vs. CC model [OR=0.72, 95%CI (0.31, 1.70), P=0.46], TC vs. CC model [OR=1.09, 95%CI (0.83, 1.43), P=0.54], recessive model [OR=1.08, 95%CI (0.68, 1.70), P=0.74], or dominant model [OR=0.77, 95%CI (0.42, 1.42), P=0.41]. For the associations between ESR1 gene intron 1 XbaⅠ polymorphisms and POF, there was no statistical difference in AA vs. GG model [OR=0.88, 95%CI (0.44, 1.75), P=0.72], AG vs. GG model [OR=1.23, 95%CI (0.84, 1.79), P=0.29], recessive model [OR=1.14, 95%CI (0.81, 1.61), P=0.44], or dominant model [OR=0.75, 95%CI (0.41, 1.35), P=0.34], either. No statistical difference was found in the ethno-based subgroup analyses (P>0.05). Most models had obvious heterogeneities.ConclusionsCurrent evidence can’t confirm the associations between ESR1 gene PvuⅡ, XbaⅠ polymorphisms and POF. High-quality, multi-central and large-sample studies are still necessary to support this conclusion.
Objective To explore the effect of interfering RNA (shRNA) on biological activity of A549 cells and tumor growth in nude mice after knockdown of estrogen receptor α (ERα) gene. Methods The ERα gene in A549 cells was knocked down by shRNA. RT-PCR and Western blot were used to detect the gene expression and protein expression after knockdown; colony formation experiment was used to detect the proliferation of cells, and RT-PCR was used to detect the expression of Ki-67 and PCNA; flow cytometry was used to detect apoptosis rate; transwell assay was used to detect cell invasion ability; Western blot was used to detect the expression of epithelial cadherin (E-cad) and neuropathic cadherin (N-cad) protein. The control group and A549 cells transfected with ERα-shRNA1 were injected subcutaneously in nude mice to construct transplanted tumors. Immunohistochemistry was used to detect the expression of Ki-67 and N-cad in tumor tissues. Results Compared with the control group, after transfection of ERα-shRNA1 and ERα-shRNA2, the mRNA and protein expressions of ERα were reduced significantly (P<0.05), and shRNA1 with high interference efficiency was used for subsequent experiments. Compared with the control group, the A549 cells were transfected with ERα-shRNA1, the colony formation rate was down-regulated significantly (P<0.05), the apoptosis rate was increased significantly (P<0.05), the expression of Ki-67 and PCNA were down-regulated significantly (P<0.05), the number of invasive cells was reduced significantly, the expression of E-cad was increased, and the expression of N-cad was decreased (P<0.05). The results of tumor formation in nude mice showed that interfering with ERα expression can significantly inhibit tumor growth (P<0.05), and down-regulate the rate of Ki-67 and N-cad positive cells (P<0.05). Conclusion Knockdown of ERα inhibits the proliferation and migration ability of NSCLC cells and the occurrence and development of transplanted tumors in nude mice.