Activation of the PI3K/AKT pathway mediates FSH-stimulated VEGF expression in ovarian serous cystadenocarclnoma

There is evidence to suggest that follicle-stimulating hormone （FSH） can facilitate the neovascularization of ovarian cancers by increasing vascular endothelial growth factor （VEGF） expression in cancer cells, although the underlying molecular mechanism of this process is not well known. Therefore, we investigated the effect of FSH on VEGF expression in the ovarian cancer cell lines SKOV-3 and ES-2. Treatment with FSH significantly increased VEGF expression in a dose- and time-dependent manner. In addition, FSH treatment enhanced the expression of survivin and hypoxlainducible factor-1 （HIF-1α）. Knockdown of survivin or HIF-1α suppressed VEGF expression, but only knockdown of survivin inhibited FSH-stimulated VEGF expression. Pretreatment with LY294002, a phosphoinositide 3-kinase （PI3K）/AKT inhibitor, neutralized the enhanced expression of survivin induced by FSH, but treatment with U0126, a mitogen-activated protein kinase/extracellular signal-regulated kinase inhibitor, had no such effect. We further showed that ovarian serous cystadenocarcinoma samples had much higher incidence of positive AKT and phosphorylated AKT （pAKT） protein staining than did benign ovarian cystadenoma samples （p 〈 0.01）. The 5-year survival rate was only about 15% in patients with ovarian serous cystadenocarcinoma who had AKT and pAKT expression, whereas it was about 80% in those who did not have AKT or pAKT expression. Taken together, these results indicate that FSH increases the expression of VEGF by upregulating the expression of survivin, which is activated by the PI3K/AKT signaling pathway. Understanding the role of the PI3K/AKT pathway in FSH-stimulated expression of survivin and VEGF will be beneficial for evaluating the prognosis for patients with ovarian serous cystadenocarcinoma and for pursulug effective treatment against this disease.

Silencing novel long non-coding RNA FKBP9P1 represses malignant progression and inhibits PI3K/AKT signaling of head and neck squamous cell carcinoma in vitro

Background:Long non-coding RNAs(lncRNAs)play key roles in human cancers.In our previous study,we demonstrated that lncRNA FKBP prolyl isomerase 9 pseudogene 1(FKBP9P1)was highly expressed in head and neck squamous cell cancer(HNSCC)tissues.However,its functional significance remains poorly understood.In the present study,we identify the role and potential molecular biologic mechanisms of FKBP9P1 in HNSCC.Methods:Quantitative real-time polymerase chain reaction was used to detect the expression of FKBP9P1 in HNSCC tissues,matched adjacent normal tissues,human HNSCC cells(FaDu,Cal-27,SCC4,and SCC9),and human immortalized keratinocytes cell HaCaT(normal control).Cal-27 and SCC9 cells were transfected with sh-FKBP9P1-1,sh-FKBP9P1-2,and normal control(sh-NC)lentivirus.Cell counting kit-8 assay,colony formation assay,wound healing assay,and trans-well assay were used to explore the biologic function of FKBP9P1 in HNSCC cells.Furthermore,western blotting was used to determine the mechanism of FKBP9P1 in HNSCC progression.Chi-squared test was performed to assess the clinical significance among FKBP9P1 high-expression and low-expression groups.Survival analyses were performed using the Kaplan-Meier method and assessed using the log-rank test.The comparison between two groups was analyzed by Student t test,and comparisons among multiple samples were performed by one-way analysis of variance and a Bonferroni post hoc test.Results:FKBP9P1 expression was significantly up-regulated in HNSCC tissues(tumor vs.normal,1.914 vs.0.957,t=7.746,P<0.001)and cell lines(P<0.01 in all HNSCC cell lines).Besides,the median FKBP9P1 expression of HNSCC tissues(1.677)was considered as the threshold.High FKBP9P1 level was correlated with advanced T stage(P=0.022),advanced N stage(P=0.036),advanced clinical stage(P=0.018),and poor prognosis of HNSCC patients(overall survival,P=0.002 and disease-free survival,P<0.001).Knockdown of FKBP9P1 led to marked repression in proliferation,migration,and invasion of HNSCC cells in vitro(P all<0.01).Mechanistically,silencing FKBP9P1 was observed to restrain the PI3K/AKT signaling pathway.Conclusions:Silencing lncRNA FKBP9P1 represses HNSCC progression and inhibits PI3K/AKT(phosphatidylinositol 3 kinase/AKT Serine/Threonine Kinase)signaling in vitro.Therefore,FKBP9P1 could be a potential new target for the diagnosis and treatment of HNSCC patients.