Investigator
First Affiliated Hospital Of Xian Jiaotong University
Downregulation of GPR4 and TCF7 Promotes Apoptosis and Inhibits Growth and Invasion of Ovarian Cancer Cells
Background: G Protein-coupled Receptor 4 (GPR4) has been reported to play essential roles in regulating the proliferation, migration and angiogenesis of vascular endothelial cells. GPR4 is also suggested to play significant roles in the growth and angiogenesis of ovarian cancer. Objective: To explore the functions of GPR4 and Transcription Factor 7 (TCF7) in ovarian cancer. Methods: The expression levels of genes involved in Wnt signaling were validated by quantitative Real-Time- PCR (q-RT-PCR). The effects of GPR4 and TCF7 on ovarian cancer cell invasion and apoptosis were determined using soft agar, transwell assay and flow cytometric assay. Protein levels of beta-catenin, MMP-2 and MMP-9 were evaluated by Western blotting. Results: In this study, we found that GPR4 and TCF7 had the capacity to control cell division by altering cell cycle distribution, anchorage-independent growth, and directional cell motility of ovarian cancer cell A2780. Also, we showed that the knockdown of GPR4 and TCF7 in ovarian cancer cell A2780 induced significant inhibitition of cell growth and invasion, as well as the promotion of apoptosis. Downregulation of TCF7 resulted in the decreased MMP-2 and MMP-9 levels. Conclusion: The results implicate that GPR4 behaves like an oncogene and may function through WNT pathway molecule TCF7. Downregulation of GPR4 and TCF7 essentially inhibited cell growth and invasion and enhanced apoptosis of ovarian cancer cells, which may lay a foundation for ovarian cancer treatment.
Long non‐coding RNA SNGH7 Is activated by SP1 and exerts oncogenic properties by interacting with EZH2 in ovarian cancer
Abstract Long non‐coding RNAs (lncRNAs) are key regulators or a range of diseases and chronic conditions such as cancers, but how they function in the context of ovarian cancer (OC) is poorly understood. The Coding‐Potential Assessment Tool was used to assess the likely protein‐coding potential of SNHG7. SNHG7 expression was elevated in ovarian tumour tissues measured by qRT‐PCR. The online database JASPAR was used to predict the transcription factors binding to SNHG7. Twenty‐four‐well Transwell plates were used for invasion assays. RNA immunoprecipitation was performed to determine RNA‐protein associations. EdU assay was introduced to detect cell proliferation. Chromatin immunoprecipitation was performed to confirm the directly interaction between DNA and protein. We discovered that in the context of OC there is a significant up‐regulation of the lncRNA SNHG7. Knocking down this lncRNA disrupted both OC cell invasion and proliferation, while its overexpression had the opposite effect. SP1 binding sites were present in the SNHG7 promoter, and chromatin immunoprecipitation (ChIP) confirmed direct SP1 binding to this region, activating SNHG7 transcription. We found that at a mechanistic level in OC cells, KLF2 is a probable SNHG7 target, as we found that SHNCCC16 directly interacts with EZH2 and thus represses KLF2 expression. In summary, this research demonstrates that lncRNA SNHG7 is an SP1‐activated molecule that contributes to OC progression by providing a scaffold whereby EZH2 can repress KLF2 expression.
Long non‐coding RNA SNHG1 stimulates ovarian cancer progression by modulating expression of miR‐454 and ZEB1
Ovarian cancer (OC) is highly prevalent and is associated with high mortality rates due to metastasis and relapse. In this study, we assessed the role of long non‐coding RNA (lncRNA) small nucleolar RNA host gene 1 (SNHG1) in OC to gain further insight into mechanisms that contribute to its aggressiveness. We analyzed the correlation between SNHG1, miR‐454 and zinc finger E‐box‐binding homeobox 1 (ZEB1) using a dual‐luciferase reporter assay. Alterations in cell metastasis and invasiveness were observed using wound‐healing and Transwell invasion assays, respectively. Tumor xenografts allowed us to monitor liver metastasis of mice injected with A2780 cells. We found that SNHG1 is overexpressed in OC. Downregulation of SNHG1 promoted miR‐454 expression and reduced ZEB1 levels. In addition, knockdown of SNHG1, also reduced the aggressiveness of A2780 and SK‐OV3 cells. Furthermore, SNHG1 downregulation by siRNA hindered cell migration and invasion; however, this effect was reversed by co‐transfection of miR‐454 into A2780 and SK‐OV3 cells. Moreover, SNHG1 increased ZEB1 expression by downregulating miR‐454 and activated Akt signaling, thereby promoting epithelial‐mesenchymal transition and enhancing the invasiveness of OC cells. Tumor xenograft analyses confirmed that SNHG1 affects OC proliferation and metastasis in vivo. In summary, our data demonstrate that SNHG1 plays crucial roles in tumor progression and may be a useful maker for OC prognosis.
PLGA‐PEG‐c(RGDfK)‐ Kushenol E Micelles With a Therapeutic Potential for Targeting Ovarian Cancer
Background: As a naturally derived inhibitor of autophagy, Kushenol E (KE) is a biprenylated flavonoid and is isolated from Sophora flavescens , which has been used for the treatment of cancer, hepatitis, and skin diseases. However, KE, as a poorly soluble drug, exhibited strong autophagy regulating activity in in vitro cancer cell lines, but no related studies have reported its antiovarian cancer property. Therefore, it is very beneficial to enhance the antineoplastic properties of KE by establishing an ovarian tumor‐targeting nanoparticle system modified with tumor‐homing c(RGDfK) peptides. Materials and Methods: In the current study, poly(lactic‐co‐glycolic acid)‐poly(ethylene glycol)‐modified with cyclic RGDfK peptide (PLGA‐PEG‐c(RGDfK))‐KE micelles (PPCKM) were prepared to overcome the poor water solubility of KE to meet the requirement of tumor‐active targeting. The effect of PPCKM on ovarian cancer was evaluated on SKOV‐3 cells and xenograft models in BALB/c nude mice. Results: The PPCKM showed a higher drug cumulative release ratio (82.16 ± 7.69% vs. 34.96 ± 3.05%, at 1.5 h) with good morphology, particle size (93.41 ± 2.84 nm), and entrapment efficiency (89.7% ± 1.3%). The cell viability, migration, and apoptosis analysis of SKOV‐3 cells demonstrated that PPCKM retained potent antitumor effects and promoted apoptosis at early and advanced stages with concentration‐dependent. Based on the establishment of xenograft models in BALB/c nude mice, we discovered that PPCKM reduced tumor volume and weight, inhibited proliferating cell nuclear antigen (PCNA) and Ki67 expression, as well as promoted apoptosis by targeting the tumor site. Conclusion: The findings in this study suggest that PPCKM may serve as an effective therapeutic option for ovarian cancer.
