RESUMO
Objective:To investigate the molecular mechanism of Qiyu Sanlong prescription （QYSL） in inhibiting the "addiction" of lung cancer A549 cells to miRNA21. Method:The human lung cancer A549 cells were routinely passaged and divided into the blank group， blank serum group， QYSL-containing serum group， and siRNA group. The prepared QYSL-containing serum was used for intervention， with the optimal concentration and action time determined in previous studies. The protein and mRNA expression levels of miRNA21 and related molecules in its target phosphatase and tensin homolog deleted on chromosome 10 （PTEN）/phosphatidylinositol 3-kinase （PI3K） signaling pathway were detected by real-time polymerase chain reaction （Real-time PCR） and Western blot assay. Result:The comparison with the blank serum group revealed that the mRNA expression levels of miRNA21 in the QYSL-containing serum group and the siRNA group were decreased， while the PTEN mRNA expression in the QYSL-containing serum group was increased， showing significant differences （<italic>P</italic><0.01）. Compared with the blank serum， the QYSL-containing serum and siRNA significantly down-regulated PI3K and mammalian target of rapamycin （mTOR） mRNA expression （<italic>P</italic><0.01）， whereas the QYSL-containing serum did not change the mRNA expression of protein kinase B （Akt）. The protein expression levels of PTEN in the QYSL-containing serum group and the siRNA group were obviously elevated in contrast to that in the blank serum group （<italic>P</italic><0.05）. Meanwhile， the protein expression levels of phosphorylated Akt （p-Akt） and phosphorylated mTOR （p-mTOR） evidently declined in the QYSL-containing serum group （<italic>P</italic><0.05）， but there was no significant reduction in total Akt and mTOR protein expression. The PI3K protein expression was slightly down-regulated， with no statistical significance. Conclusion:QYSL inhibits the transcription of miRNA21， increases the expression of PTEN， and reduces the expression of key molecules in PI3K/Akt/mTOR signaling pathway， thus mildly inhibiting the "addiction" of lung cancer cells to oncogenes and blocking their proliferation.
RESUMO
Background and purpose:Loss of the tumor suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is one of the most common somatic genetic aberrations in prostate cancer in Western countries and is frequently associated with tumor progression and poor prognosis. This study aimed to investigate the frequency of PTEN protein loss in Chinese prostate cancer patients and to determine its association with the biochemical recurrence of prostate cancer.Methods:The data from 225 diagnosed localized prostate cancer patients with radical prostatectomy from 2006 to 2011 were collected retrospectively, including patient’s age at diagnosis, prostate-speciifc antigen (PSA) level at diagnosis, Gleason score, clinical stage, surgical margin, and time to biochemical recurrence or not. This study performed PTEN protein immunohistochemistry on tissue microarrays, which were made from 225 Chinese prostate cancer patients mentioned above, treated by radical prostatectomy with one case including 2 cancer spots and 2 adjacent normal gland spots. Correlations of PTEN loss with clinicopathological features were analyzed usingχ2 test. Kaplan-Meier survival model and Cox proportional hazards regression model were used to evaluate the predictive role of PTEN protein expression and patient characteristics for biochemical recurrence. Results:PTEN protein loss was observed in 15% of the patients and was associated with increased preoperative PSA levels (P=0.03) and old age (P=0.009). In univariate Kaplan–Meier analysis, the factors associated with the biochemical recurrence of prostate cancer included PSA levels (P=0.000 4), Gleason sum (P=0.019 8), and PTEN status (P=0.013 1). In multivariable Cox regression analysis, PTEN expression (HR=0.536, P=0.044), PSA levels (HR=1.879, P=0.001), and Gleason score (HR=1.361,P=0.03) were signiifcant in predicting biochemical recurrence of prostate cancer.Conclusion:PTEN protein loss is associated with an increased risk of recurrence, independent of known clinicopathological factors.
RESUMO
Objective To analyse the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in ovarian epithelial cancer and to investigate the relationship between PTEN and clinical pathology and prognosis of ovarian epithelial cancer.Methods Expression of PTEN in 10 normal ovarian tissues,20 benign tumors and 60 cases of ovarian epithelial cancers were detected by immunohistochemical method.Results The positive expression of PTEN in normal ovarian and benign tumor tissues were significantly higher than that in ovarian epithelial cancers (100％ (10/10) vs 80.0％ (16/20) vs 53.3％ (32/60),x2 =7.778 and 4.444 respectively,P ＜ 0.05).The expression of PTEN was correlated to clinical stage,histilogical grade,presence and metastasis of lymph node (x2 =4.339;6.465 ;3.896;10.452;P ＜0.01),but there was no correlation to age,histological type and ascites (x2 =0.004 ;0.388 ; 1.057 ; P ＞ 0.05).Conclusion The expression of PTEN is related to ovarian carcinogenesis and development and may has great value in clinical diagnosis and prognosis of ovarian carcinogenesis.
RESUMO
Recently,phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is suggested as a new agent in the fighting against fibrogenesis.In tumor,DJ-1 is identified as a negative regulator of PTEN.But the expression of DJ-1 and the regulation of PTEN in fibrosis are unclear.Renal fibrosis was induced in 5/6 subtotal nephrectomy rat model.Human proximal tubular epithelial cells (HKC) were treated with transforming growth factor-beta 1 (TGF-β1),or transfected with DJ-1 or PTEN.Confocal microscope was used to investigate the localization of DJ-1 and PTEN.The selective phosphoinositide-3 kinase (PI3K) inhibitor,LY294002,was administered to inhibit PI3K pathway.The DJ-1 and PTEN expression,markers of epithelial-mesenchymal transition (EMT) and Akt phosphorylation were measured by RT-PCR,Western blotting or immunocytochemistry.In vitro,after HKC cells were stimulated with 10 ng/mL TGF-β1 for 72 h,the expression of DJ-1 was increased,and that of PTEN was decreased.In vivo,the same results were identified in 5/6-nephrectomized rats.In normal HKC cells,most of DJ-1 protein localized in cytoplasm,and little in nucleus.TGF-β1 upregulated DJ-1 expression in both cytoplasma and nuclei.In contrary,TGF-β1 emptied cytoplasmic PTEN protein into nucleus.Overexpression of D J-1 decreased the expression of PTEN,promoted the activation of Akt and the expression of vimentin,and also led to the loss of cytoplasmic PTEN.Contrarily,overexpression of PTEN protected HKC cells from TGF-β1-induced EMT.In conclusion,DJ-1 is upregulated in renal fibrosis and DJ-1 mediates EMT by suppressing cytoplasmic PTEN expression and Akt activation.