Effect and Mechanism of Atorvastatin on Reversing Drug Resistance in Leukemia by Regulating Glycolysis through PTEN/mTOR Pathway / 中国实验血液学杂志

OBJECTIVE@#To investigate the influence and mechanism of atorvastatin on glycolysis of adriamycin resistant acute promyelocytic leukemia (APL) cell line HL-60/ADM.@*METHODS@#HL-60/ADM cells in logarithmic growth phase were treated with different concentrations of atorvastatin, then the cell proliferation activity was measured by CCK-8 assay, the apoptosis was detected by flow cytometry, the glycolytic activity was checked by glucose consumption test, and the protein expressions of PTEN, p-mTOR, PKM2, HK2, P-gp and MRP1 were detected by Western blot. After transfection of PTEN-siRNA into HL-60/ADM cells, the effects of low expression of PTEN on atorvastatin regulating the behaviors of apoptosis and glycolytic metabolism in HL-60/ADM cells were further detected.@*RESULTS@#CCK-8 results showed that atorvastatin could inhibit the proliferation of HL-60/ADM cells in a concentration-dependent and time-dependent manner (r=0.872, r=0.936), and the proliferation activity was inhibited most significantly when treated with 10 μmol/L atorvastatin for 24 h, which was decreased to (32.3±2.18)%. Flow cytometry results showed that atorvastatin induced the apoptosis of HL-60/ADM cells in a concentration-dependent manner (r=0.796), and the apoptosis was induced most notably when treated with 10 μmol/L atorvastatin for 24 h, which reached to (48.78±2.95)%. The results of glucose consumption test showed that atorvastatin significantly inhibited the glycolytic activity of HL-60/ADM cells in a concentration-dependent and time-dependent manner (r=0.915, r=0.748), and this inhibition was most strikingly when treated with 10 μmol/L atorvastatin for 24 h, reducing the relative glucose consumption to (46.53±1.71)%. Western blot indicated that the expressions of p-mTOR, PKM2, HK2, P-gp and MRP1 protein were decreased in a concentration-dependent manner (r=0.737, r=0.695, r=0.829, r=0.781, r=0.632), while the expression of PTEN protein was increased in a concentration-dependent manner (r=0.531), when treated with different concentrations of atorvastatin for 24 h. After PTEN-siRNA transfected into HL-60/ADM cells, it showed that low expression of PTEN had weakened the promoting effect of atorvastatin on apoptosis and inhibitory effect on glycolysis and multidrug resistance.@*CONCLUSION@#Atorvastatin can inhibit the proliferation, glycolysis, and induce apoptosis of HL-60/ADM cells. It may be related to the mechanism of increasing the expression of PTEN, inhibiting mTOR activation, and decreasing the expressions of PKM2 and HK2, thus reverse drug resistance.

MiR-30e-5p overexpression promotes proliferation and migration of colorectal cancer cells by activating the CXCL12 axis via downregulating PTEN / 南方医科大学学报

OBJECTIVE@#To investigate the regulatory effects of miR-30e-5p on biological behaviors of colorectal cancer cells and the role of PTEN/CXCL12 axis in mediating these effects.@*METHODS@#Bioinformatic analysis was performed to explore the differential expression of miR-30e-5p between colorectal cancer tissues and normal tissues. RT-qPCR was used to detect the differential expression of miR-30e-5p in intestinal epithelial cells and colorectal cancer cells. Bioinformatics and dual luciferase assay were used to predict and validate the targeting relationship between miR-30e-5p and PTEN. Human and murine colorectal cancer cell lines were transfected with miR-30e-5p mimics, miR-30e-5p inhibitor, miR-30e-5p mimics+LV-PTEN, or miR-30e-5p inhibitor + si-PTEN. The changes in biological behaviors of the cells were detected using plate clone formation assay, CCK-8 assay, flow cytometry, scratch healing and Transwell assays. PTEN and CXCL12 expressions in the cancer cells were detected by Western blotting. The effects of miR-30e-5p inhibitor on colorectal carcinogenesis and development were observed in nude mice.@*RESULTS@#Bioinformatic analysis showed that miR-30e-5p expression was significantly elevated in colorectal cancer tissues compared with the adjacent tissue (P < 0.01). Higher miR-30e-5p expression was detected in colorectal cancer cell lines than in intestinal epithelial cells (P < 0.01). Dual luciferase assay confirmed the targeting relationship between miR-30e-5p and PTEN (P < 0.05). Transfection with miR-30e-5p mimics significantly enhanced proliferation and metastasis and inhibited apoptosis of the colorectal cancer cells (P < 0.05), and co-transfection with LV-PTEN obviously reversed these changes (P < 0.05). MiR-30e-5p mimics significantly inhibited PTEN expression and enhanced CXCL12 expression in the cancer cells (P < 0.01), and miR-30e-5p inhibitor produced the opposite effect. Transfection with miR-30e-5p inhibitor caused cell cycle arrest in the cancer cells, which was reversed by co-transfection with si-PTEN (P < 0.05). In the in vivo experiments, the colorectal cancer cells transfected with miR-30e-5p inhibitor showed significantly lowered tumorigenesis.@*CONCLUSION@#Overexpression of miR-30e-5p promotes the malignant behaviors of colorectal cancer cells by downregulating PTEN to activate the CXCL12 axis.

Shaofu Zhuyu Decoction attenuates fibrosis in endometriosis through regulating PTEN/Akt/mTOR signaling pathway / 中国中药杂志

The present study aimed to investigate the protective role of Shaofu Zhuyu Decoction(SFZY) against endometriosis fibrosis in mice, and decipher the underlying mechanism through the phosphatase and tensin homolog deleted on chromosome ten(PTEN)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) pathway. Eighty-five BALB/c female mice were randomly assigned into a blank group, a model group, high-, medium, and low-dose SFZY(SFZY-H, SFZY-M, and SFZY-L, respectively) groups, and a gestrinone suspension(YT) group. The model of endometriosis was induced by intraperitoneal injection of uterine fragments. The mice in different groups were administrated with corresponding groups by gavage 14 days after modeling, and the blank group and model group with equal volume of distilled water by gavage. The treatment lasted for 14 days. The body weight, paw withdrawal latency caused by heat stimuli, and total weight of dissected ectopic focus were compared between different groups. The pathological changes of the ectopic tissue were observed via hematoxylin-eosin(HE) and Masson staining. Real-time PCR was employed to measure the mRNA levels of α-smooth muscle actin(α-SMA) and collagen type Ⅰ(collagen-Ⅰ) in the ectopic tissue. The protein levels of PTEN, Akt, mTOR, p-Akt, and p-mTOR in the ectopic tissue were determined by Western blot. Compared with the blank group, the modeling first decreased and then increased the body weight of mice, increased the total weight of ectopic focus, and shortened the paw withdrawal latency. Compared with the model group, SFZY and YT increased the body weight, prolonged the paw withdrawal latency, and decreased the weight of ectopic focus. Furthermore, the drug administration, especially SFZY-H and YT(P<0.01), recovered the pathological and reduced the area of collagen deposition. Compared with the blank group, the modeling up-regulated the mRNA levels of α-SMA and collagen-Ⅰ in the ectopic focus, and such up-regulation was attenuated after drug intervention, especially in the SFZY-H and YT groups(P<0.05,P<0.01). Compared with the blank group, the modeling down-regulated the protein level of PTEN and up-regulated the protein levels of Akt, mTOR, p-Akt, and p-mTOR(P<0.01, P<0.001). Drug administration, especially SFZY-H and YT, restored such changes(P<0.01). SFZY may significantly attenuate the focal fibrosis in the mouse model of endometriosis by regulating the PTEN/Akt/mTOR signaling pathway.

Prognostic value of PTEN in de novo diagnosed metastatic prostate cancer / 亚洲男科学杂志(英文版)

The purpose of our study is to investigate the prognostic value of phosphatase and tensin homolog on chromosome 10 (PTEN) expression in patients with de novo metastatic castration naïve prostate cancer (mCNPC). A total of 205 patients with mCNPC at Fudan University Shanghai Cancer Center (Shanghai, China) were retrospectively examined. Immunohistochemical staining of PTEN was performed on prostate biopsy samples of these patients. Associations among clinicopathological features, patient survival and PTEN protein expression were analyzed. PTEN loss occurred in 58 of 205 (28.3%) patients. Loss of PTEN was significantly correlated with high metastatic volume (P = 0.017). No association between PTEN expression and Gleason score was observed. Patients with PTEN loss had significantly shorter progression-free survival (PFS, P < 0.001) and overall survival (OS, P < 0.001) compared with patients with intact PTEN expression. Multivariate analysis showed that elevated alkaline phosphatase, high metastatic volume and PTEN loss were independent poor prognostic factors for PFS. The Eastern Cooperative Oncology Group performance status (ECOG PS)#8805; 2 and PTEN loss were independent poor prognostic factors for OS. The adjusted hazard ratio of PTEN loss for PFS and OS was 1.67 (95% confidence interval [CI]: 1.14-2.43, P = 0.008) and 1.95 (95% CI: 1.23-3.10, P = 0.005), respectively. PTEN loss was also significantly associated with shorter PFS (P = 0.025) and OS (P < 0.001) in patients with low-volume metastatic disease. Our data showed that PTEN loss is an independent predictor for shorter PFS and OS in patients with de novo mCNPC.

Cancer cells corrupt normal epithelial cells through miR-let-7c-rich small extracellular vesicle-mediated downregulation of p53/PTEN / 国际口腔科学杂志·英文版

Tumor volume increases continuously in the advanced stage, and aside from the self-renewal of tumor cells, whether the oncogenic transformation of surrounding normal cells is involved in this process is currently unclear. Here, we show that oral squamous cell carcinoma (OSCC)-derived small extracellular vesicles (sEVs) promote the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of normal epithelial cells but delay their apoptosis. In addition, nuclear-cytoplasmic invaginations and multiple nucleoli are observed in sEV-treated normal cells, both of which are typical characteristics of premalignant lesions of OSCC. Mechanistically, miR-let-7c in OSCC-derived sEVs is transferred to normal epithelial cells, leading to the transcriptional inhibition of p53 and inactivation of the p53/PTEN pathway. In summary, we demonstrate that OSCC-derived sEVs promote the precancerous transformation of normal epithelial cells, in which the miR-let-7c/p53/PTEN pathway plays an important role. Our findings reveal that cancer cells can corrupt normal epithelial cells through sEVs, which provides new insight into the progression of OSCC.

Effects of leptin on proliferation and differentiation of hypoxic rat retinal progenitor cells in vitro / 南方医科大学学报

OBJECTIVE@#To investigate the the effects of leptin on the proliferation, differentiation and PTEN expression of rat retinal progenitor cells (RPCs) cultured under hypoxic condition.@*METHODS@#SD rat RPCs were cultured in normoxic conditions or exposed to hypoxia in the presence of 0, 0.3, 1.0, 3.0, 10, and 30 nmol/L leptin for 12, 48 and 72 h, and the cell viability was assessed using cell counting kit 8 (CCK 8) assay. The RPCs in primary culture were divided into control group, hypoxia group, and hypoxia+leptin group, and after 48 h of culture, the cell medium was replaced with differentiation medium and the cells were further cultured for 6 days. Immunofluorescence staining was employed to detect the cells positive for β-tubulin III and GFAP, and Western blotting was used to examine the expression of PTEN at 48 h of cell culture.@*RESULTS@#The first generation of RPCs showed suspended growth in the medium with abundant and bright cellular plasma and formed mulberry like cell spheres after 2 days of culture. Treatment with low-dose leptin (below 3.0 nmol/L) for 48 h obviously improved the viability of RPCs cultured in hypoxia, while at high concentrations (above 10 nmol/L), leptin significantly suppressed the cell viability (P < 0.05). The cells treated with 3.0 nmol/L leptin for 48 h showed the highest viability (P < 0.05). After treatment with 3.0 nmol/L leptin for 48 h, the cells with hypoxic exposure showed similar GFAP and β-tubulin Ⅲ positivity with the control cells (P>0.05), but exhibited an obvious down-regulation of PTEN protein expression compared with the control cells (P < 0.05).@*CONCLUSION@#In rat RPCs with hypoxic exposure, treatment with low dose leptin can promote the cell proliferation and suppress cellular PTEN protein expression without causing significant effects on cell differentiation.

Effects of adenovirus-mediated shRNA down-regulates PTEN expression on fibril-binding proteins vinculin, filamin A and cortactin in activated hepatic stellate cells / 中华肝脏病杂志

Objective: To investigate the effect of adenovirus-mediated shRNA down-regulating phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression on vinculin, filamin A, and cortactin in activated hepatic stellate cells (HSCs). Methods: Activated rats hepatic stellate cell line (HSC-T6) was cultured in vitro. Recombinant adenovirus Ad-shRNA/PTEN carrying PTEN targeted RNA interference sequence [short hairpin RNA (shRNA)] and empty control virus Ad-GFP were transfected into HSCs. The PTEN mRNA and protein expression of HSCs in each group were detected by real-time fluorescence quantitative PCR and Western blot. The expressional change of vinculin, filamin A and cortactin in HSCs of each group were detected by confocal laser scanning immunofluorescence microscope. Image-pro plus 6.0 software was used for image analysis and processing. The integrated optical density (IOD) of the fluorescence protein expression was measured. The experiment was divided into three groups: control group (DMEM instead of adenovirus solution in the adenovirus transfection step), Ad-GFP group (transfected with empty virus Ad-GFP only expressing green fluorescent protein), and Ad-shRNA/PTEN group (recombinant adenovirus Ad-shRNA/PTEN carrying shRNA targeting PTEN and expressing green fluorescent protein). One-way analysis of variance was used for comparison of mean value among the three groups, and LSD-test was used for comparison between the groups. Results: shRNA targeted PTEN was successfully transfected and the expression of PTEN mRNA and protein in HSC (P < 0.05) was significantly down-regulated. HSCs vinculin was mainly expressed in the cytoplasm. HSCs vinculin fluorescence IOD in the Ad-shRNA/PTEN group (19 758.83 ± 1 520.60) was higher than control (7 737.16 ± 279.93) and Ad-GFP group (7 725.50 ± 373.03) (P < 0.05), but there was no statistically significant difference between control group and Ad-GFP group (P > 0.05). There was no statistically significant difference in the fluorescence IOD of Filamin A among the three groups (P > 0.05), but the subcellular distribution of Filamin A among the three groups were changed. Filamin A in the Ad-shrNA /PTEN HSC group was mainly distributed in the cytoplasm. Filamin A HSC was mainly located in the nucleus.The filamin A HSC in the control group and Ad-GFP group was mainly located in the nucleus. The nucleocytoplasmic ratio of Filamin A in the AD-shrNA /PTEN group (0.60 ± 0.15) was significantly lower than control group (1.20 ± 0.15) and Ad-GFP group (1.08 ± 0.23), P < 0.05. but there was no statistically significant difference in filamin A nucleocytoplasmic ratio of HSC between the control group and the Ad-GFP group (P > 0.05). Cortactin HSCs in the three groups was mainly distributed in the cytoplasm. The cortactin fluorescence IOD of HSCs in the Ad-shRNA/PTEN group was significantly higher than control group (22 959.94 ± 1 710.42) and the Ad-GFP group (22 547.11 ± 1 588.72 ) (P < 0.05), while there was no statistically significant difference in the IOD of cortactin fluorescence in HSCs between the control group and the Ad-GFP group (P > 0.05). Conclusion: The down-regulation of PTEN expression raises the expression of microfilament-binding protein vinculin and cortactin, and changes the subcellular distribution of another microfilament binding protein filamin A, that is, translocation from nucleus to the cytoplasm in activated HSC in vitro.

MicroRNA-92b augments sorafenib resistance in hepatocellular carcinoma via targeting PTEN to activate PI3K/AKT/mTOR signaling

Sorafenib (SOR) resistance is still a significant challenge for the effective treatment of hepatocellular carcinoma (HCC). The mechanism of sorafenib resistance remains unclear. Several microRNAs (miRNAs) have been identified as playing a role in impairing the sensitivity of tumor cells to treatment. We examined the mechanism behind the role of miR-92b in mediating sorafenib resistance in HCC cells. We detected that miR-92b expression was significantly upregulated in SOR-resistant HepG2/SOR cells compared to parental HepG2/WT cells. After transfection with miR-92b inhibitor, the proliferation of HepG2/SOR cells was remarkably weakened and rates of apoptosis significantly increased. PTEN was considered to be a functional target of miR-92b according to a luciferase reporter assay. Knockdown of PTEN significantly impaired the ability of miR-92b inhibitor on increasing sorafenib sensitivity of HepG2/SOR cells. Furthermore, we confirmed by western blotting and immunofluorescence that miR-92b can mediate sorafenib resistance by activating the PI3K/AKT/mTOR pathway in HCC cells by directly targeting PTEN. These findings further validate the mechanism of miR-92b in SOR resistance in HCC treatment.

Effect of resveratrol on PTEN expression and fibrosis of renal tubular epithelial cells in a high-glucose environment / 中国中药杂志

This study explored the effects of resveratrol(Res) on the expression of phosphatase and tensin homolog deleted on chromosome ten(PTEN) and the fibrosis of rat renal tubular epithelial cells in a high-glucose environment and the possible mechanism underlying the fibrosis reduction. After the pretreatment of rat renal tubular epithelial cells(NRK-52 E) cultured in a high-glucose condition with Res or PTEN inhibitor SF1670, they were divided into several groups, i.e., normal glucose(NG), normal glucose + SF1670(NS), high glucose(HG), high glucose + SF1670(HS), high glucose + Res at different concentrations(5, 10, 25 μmol·L~(-1)). The expression and distribution of E-cadherin and α-SMA in renal tubular epithelial cells were observed by immunofluorescence cytochemistry. The protein expression levels of PTEN, E-cadherin, α-SMA, p-Akt~((Thr308)) and collagen Ⅳ were determined by Western blot. Real-time PCR was employed to detect the expression of PTEN mRNA. Compared with the NG group, the HG group witnessed the reduced expression of PTEN mRNA, PTEN protein and E-cadherin protein, but saw the increased expression of α-SMA, p-Akt~((Thr308)) and collagen Ⅳ proteins. Besides, with the increase in Res concentration, the expression levels of PTEN mRNA, PTEN protein and E-cadherin protein gradually increased, while those of α-SMA, collagen Ⅳ, p-Akt~((Thr308)) proteins gradually decreased in the Res groups, showing a dose-effect dependence, compared with the HG group. No distinct difference was found between the NS group and the NG group. The expression level of E-cadherin was even lower and those of α-SMA, p-Akt~((Thr308)), and collagen Ⅳ were higher in the HS group than in the HG group, with no marked difference shown in the two groups in terms of PTEN mRNA and protein. Although the PTEN inhibitor did not affect PTEN, the expression changes of the other proteins were opposite to the results after Res treatment and the fibrosis was aggravated, which suggested that SF1670 promoted the fibrosis by inhibiting PTEN, activating Akt and increasing the synthesis of collagen Ⅳ and other extracellular matrix. The results show that Res can antagonize the high glucose-mediated fibrosis of renal tubular epithelial cells. This may be achieved via the up-regulation of PTEN and the inhibition of PI3 K/Akt signaling pathway.

SNHG1 promotes MPP+-induced cytotoxicity by regulating PTEN/AKT/mTOR signaling pathway in SH-SY5Y cells via sponging miR-153-3p

BACKGROUND: Long non-coding RNA small molecule RNA host gene 1 (SNHG1) was previously identified to be relevant with Parkinson's disease (PD) pathogenesis. This work aims to further elucidate the regulatory networks of SNHG1 involved in PD. Methods: 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-hydrochloride (MPTP)-induced mice and 1-methyl-4-phenylpyridinium (MPP+)-treated SH-SY5Y cells were respectively constructed as the in vivo and in vitro PD models. Expression levels of SNHG1 and miR-153-3p were detected by qRT-PCR. Protein expression levels of phosphate and tension homology deleted on chromosome ten (PTEN) were measured by western blotting assay. Cell viability and apoptosis were determined by MTT and flow cytometry assays. The interactions among SNHG1, miR-153-3p and PTEN were identified by luciferase reporter assay, RNA immunoprecipitation, and/or RNA pull-down analysis. RESULTS: Increased SNHG1 expression was found in midbrain of MPTP-induced PD mice and MPP+-treated SH-SY5Y cells. Overexpression of SNHG1 lowered viability and enhanced apoptosis in MPP+-treated SH-SY5Y cells. Moreover, SNHG1 acted as a molecular sponge to inhibit the expression of miR-153-3p. Furthermore, miR-153-3p-mediated suppression of MPP+-induced cytotoxicity was abated following SNHG1 up-regulation. Additionally, PTEN was identified as a direct target of miR-153-3p, and SNHG1 could serve as a competing endogenous RNA (ceRNA) of miR-153-3p to improve the expression of PTEN. Besides, enforced expression of PTEN displayed the similar functions as SNHG1 overexpression in regulating the viability and apoptosis of MPP+-treated SH-SY5Y cells. Finally, SNHG1 was found to activate PTEN/AKT/mTOR signaling pathway in SH-SY5Y cells by targeting miR-153-3p. CONCLUSION: SNHG1 aggravates MPP+-induced cellular toxicity in SH-SY5Y cells by regulating PTEN/AKT/mTOR signaling via sponging miR-153-3p, indicating the potential of SNHG1 as a promising therapeutic target for PD.

MicroRNA-23a knockdown attenuates angiotensin Ⅱ induced hypertrophy in rat H9c2 cells via activating PTEN and AMPK pathway / 中华心血管病杂志

Objective: To investigate if microRNA (miR) -23a knockdown could attenuate angiotensin Ⅱ(AngⅡ) induced cardiac hypertrophy by activating phosphatase and tensin homolog deleted on chromosome ten(PTEN) and AMP-activated protein kinase(AMPK) pathway. Methods: Rat H9c2 cells were cultured in DMEM high glucose medium and put in 5% CO(2) incubator at 37 ℃(normal group). After 48 hours of culture, H9c2 cells were stimulated with 10 nmol/L AngⅡ to establish cell hypertrophy model (AngⅡgroup). The H9c2 cells were inoculated in a 6-well cell culture plate and cultured in an incubator at 37 ℃. When the confluence degree of cell growth was about 70%, the cells were transfected with different reagents, and 24 hours after transfection, 10 nmol/L AngⅡ was used to interfere with the cells. The H9c2 cells were divided into different groups according to the reagents, namely AngⅡ+anti-miR group(transfected with miR-23a inhibitor), Ang Ⅱ+NC group(transfected with miR-23a inhibitor negative control), Ang Ⅱ+anti-miR+si-PTEN group(cotransfected with miR-23a inhibitor and PTEN small interference RNA(siRNA)), and AngⅡ+anti-miR+si-NC group(cotransfected with miR-23a inhibitor and PTEN siRNA negative control). The surface area of single cell was measured by Image J software.The mRNA expression levels of α-actin 1 (ACTA1) and β-myosin heavy chain (β-MHC) and miR-23a were detected by quantitative real-time PCR(qRT-PCR). The expression levels of PTEN and AMPK signal pathway related proteins were detected by Western blot. In order to verify whether miR-23a targets PTEN gene, double luciferase reporter gene experiment was performed. The luciferase reporter gene vector recombinant plasmids of wild type pGL-WT-PTEN and mutant pGL-MUT-PTEN were constructed and prepared after normal sequencing. H9c2 cells was inoculated into 24-well cell culture plate and cultured overnight in 37 ℃ incubator. The cells were co-transfected with miR-23a mimic or miR-23a mimic negative control and wild type or mutant reporter gene recombinant plasmid. Forty-eight hours after transfection, firefly luciferase activity and sea kidney luciferase activity were measured, and the ratio of them was recorded as relative luciferase activity. Results: Compared with the normal group, the cell surface area, the mRNA expression levels of ACTA1, β-MHC and miR-23a were significantly higher, while the protein expression levels of PTEN and p-AMPK were significantly lower in the Ang Ⅱ group(all P<0.05). The results of double luciferase reporter gene assay showed that the relative luciferase activity of cells co-transfected with miR-23a mimic and wild-type reporter gene recombinant plasmid was lower than that of miR-23a mimic negative control (P<0.05), and PTEN served as the target gene of miR-23a. In AngⅡ+anti-miR group the mRNA expression levels of miR-23a, ACTA1 and β-MHC were lower, and the cell surface area was smaller, while the protein expression levels of PTEN and p-AMPK were higher than that in AngⅡ group and AngⅡ+NC group(all P<0.05). Compared with AngⅡ+anti-miR group, the cell surface area was bigger, the expression of ACTA1 and β-MHC mRNA was up-regulated, and the protein expression levels of PTEN and p-AMPK were down-regulated in Ang Ⅱ+anti-miR+si-PTEN group(all P<0.05). Conclusion: Inhibition of miR-23a can attenuate Ang Ⅱ-induced hypertrophy in H9c2 cells through targeting PTEN and activating AMPK signaling pathway.

Puerarin inhibits hepatocellular carcinoma invasion and metastasis through miR-21-mediated PTEN/AKT signaling to suppress the epithelial-mesenchymal transition

Hepatocellular carcinoma (HCC) is one of the most common primary malignant tumors of the liver worldwide. Liver resection and transplantation are currently the only effective treatments; however, recurrence and metastasis rates are still high. Previous studies have shown that the epithelial-mesenchymal transition (EMT) is a key step in HCC invasion and metastasis. Inhibition of EMT has become a new therapeutic strategy for tumors. Recently, puerarin, a well-characterized component of traditional Chinese medicine, has been isolated from Pueraria radix and exerts positive effects on many diseases, particularly cancers. In this study, CCK-8, EdU immunofluorescence, colony formation, wound healing, and migration assays were used to detect the effects of puerarin on HCC cells. We further analyzed the relationship between puerarin and miR-21/PTEN/EMT markers in HCC cell lines. Our results showed that HCC cell proliferation, migration, invasion, tumor formation, and metastasis were reduced by puerarin in vitro and in vivo. Additionally, puerarin inhibited the EMT process of HCC by affecting the expression of Slug and Snail. Moreover, oncogenic miR-21 was inhibited by puerarin, coupled with an increase in the tumor suppressor gene PTEN. Increasing miR-21 expression or decreasing PTEN expression reversed the inhibition effects of puerarin in HCC. These data confirmed that puerarin affects HCC through the miR-21/PTEN/EMT regulatory axis. Overall, puerarin may represent a chemopreventive and/or chemotherapeutic agent for HCC treatment.

miR-26a-5p protects against myocardial ischemia/reperfusion injury by regulating the PTEN/PI3K/AKT signaling pathway

Reperfusion strategies in acute myocardial infarction (AMI) can cause a series of additional clinical damage, defined as myocardial ischemia/reperfusion (I/R) injury, and thus there is a need for effective therapeutic methods to attenuate I/R injury. miR-26a-5p has been proven to be an essential regulator for biological processes in different cell types. Nevertheless, the role of miR-26a-5p in myocardial I/R injury has not yet been reported. We established an I/R injury model in vitro and in vivo. In vitro, we used cardiomyocytes to simulate I/R injury using hypoxia/reoxygenation (H/R) assay. In vivo, we used C57BL/6 mice to construct I/R injury model. The infarct area was examined by TTC staining. The level of miR-26a-5p and PTEN was determined by bioinformatics methods, qRT-PCR, and western blot. In addition, the viability and apoptosis of cardiomyocytes were separately detected by MTT and flow cytometry. The targeting relationship between miR-26a-5p and PTEN was analyzed by the TargetScan website and luciferase reporter assay. I/R and H/R treatment induced myocardial tissue injury and cardiomyocyte apoptosis, respectively. The results showed that miR-26a-5p was down-regulated in myocardial I/R injury. PTEN was found to be a direct target of miR-26a-5p. Furthermore, miR-26a-5p effectively improved viability and inhibited apoptosis in cardiomyocytes upon I/R injury by inhibiting PTEN expression to activate the PI3K/AKT signaling pathway. miR-26a-5p could protect cardiomyocytes against I/R injury by regulating the PTEN/PI3K/AKT pathway, which offers a potential approach for myocardial I/R injury treatment.

Expresión inmunohistoquímica de homólogo de fosfatasa y tensina en glioblastoma multiforme y su relación con sobrevida / Immunohistochemical expression of phosphatase and tensin homologue in glioblastoma multiforme and its relationship to survival

El glioblastoma multiforme es el subtipo de gliomas más frecuente en adultos, con una pobre sobrevida promedio posterior al diagnóstico incluso si se aplica el tratamiento óptimo. Se ha estudiado marcadores tumorales de buen pronóstico, siendo controversial la expresión del homólogo de fosfatasa y tensina. Se estudió muestras parafinadas obtenidas de pacientes con glioblastoma multiforme en el Hospital Carlos Van Buren de Valparaíso, Chile, entre 2010 y 2014. Se realizó análisis inmunohistoquímico para expresión de homólogo de fosfatasa y tensina, estudiándose la intensidad y el patrón de expresión en astrocitos y células epiteliales, además de revisión de datos clínicos. Análisis estadístico utilizando SPSS v20. Se estudió la expresión de PTEN en 21 pacientes. Un 52,4 % presentó una baja expresión en núcleos de astrocitos, con un promedio de sobrevida de 14,2 meses comparado con 10,2 meses del grupo con alta expresión (p=0,33). Se encontró una intensa expresión endotelial en tejido tumoral, comparado con tejido cerebral sin tumor. Se encontró una relación entre la expresión nuclear en astrocitos con diferencias en el tiempo de sobrevida, aunque no estadísticamente significativa, requiriéndose nuevos estudios para corroborarlo. La intensa expresión endotelial observada en tejido tumoral debe ser analizada de forma dirigida.

Glioblastoma multiforme is the most frequent glioma subtype in adults, with poor survival rate after diagnosis even applying the optimal treatment. Tumoural markers have been studied looking for good prognosis, being the phosphatase and tensin homologue controversial. Paraffined samples were used from Carlos Van Buren Hospital in Valparaíso, Chile, between 2010 and 2014. An immunohistochemical analysis was performed looking for phosphatase and tensing homologue expression, studying the intensity and expression pattern in astrocytes and epithelial cells, in addition to clinical data. Statistical analysis was performed using SPSS v20. It was studied the phosphatase and tensin homologue expression in 21 patients. In the study, 52,4 % presented low expression in astrocytic glial cell nuclei, with a survival mean of 14.2 months in comparison to 10.2 months in the high expression group (p=0.33). A very intense endothelial expression was found in tumoural tissue, in comparison to the tissue without tumor. A relation between nuclear expression in astrocytes and survival rate was found, although no statistically significant. The intense endothelial expression seen in tumoural tissue must be studied directly.

PTEN loss in Gleason grade 7 prostate tumors exhibits intratumoral heterogeneity and is associated with unfavorable pathological features

Background: PTEN loss is observed in 20­30% of prostate cancers and is associated with a poor outcome, but clinical details of the impact of this biomarker are unclear for intermediate grade tumors. Methods: We investigated 43 radical prostatectomy-derived grade 7 prostate tumors from the Clinics Hospital of Ribeirão Preto. Tissue microarray (TMA) blocks were constructed and PTEN copy number status was determined for all patients through fluorescence in situ hybridization (FISH). To determine the presence of PTEN protein loss in our study cohort, we performed immunohistochemistry (IHC) in TMA sections. We then developed an automated algorithm in HALO™ to identify regions of PTEN protein loss in whole prostate scanned sections from ten patients with known PTEN deletion status by FISH. Clinical analyses were conducted to determine the associations between PTEN loss and patient outcome. All statistical analyses were conducted in R v3.4.3 with P-values below 0.05 being considered statistically significant. Results: In this study of 43 grade 7 tumors, we found PTEN deletions by FISH in 18.9% of tumors, and PTEN protein loss by IHC in 16.3% of tumors. Both techniques were highly concordant and complementary. Clinical analysis demonstrated that PTEN deletion by FISH was significantly associated with positive margin invasion (P = 0.04) and Gleason score upgrade (P = 0.001). Digital image analysis of ten representative tumors demonstrated distinct intratumoral heterogeneity for PTEN protein loss in four tumors. Conclusions: This study shows that PTEN loss in Gleason grade 7 tumors can be heterogeneous and that a systematic analysis of this biomarker using a combination of FISH, IHC, and digital imaging may identify patients with a greater risk of poor outcome (AU)

Jab1 Silencing Inhibits Proliferation and Sensitizes to Cisplatin in Biliary Tract Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Jab1 is a coactivator of c-Jun that enhances the transcriptional function of c-Jun. Jab1 is frequently overexpressed in various cancers and is associatedwith poor prognosis of cancer patients. Thus, Jab1 could be a potential therapeutic target in cancer. However, the role of Jab1 in biliary tract cancer (BTC) has not been studied. MATERIALS AND METHODS: We performed in vitro and in vivo experiments to evaluate the therapeutic potential ofJab1 inhibition in BTC. RESULTS: Among 8 BTC cell lines, many showed higher Jab1 expression levels. In addition, Jab1 silencing by siRNA increased p27 expression levels. SNU478 and HuCCT-1 cells exhibited profound Jab1 knockdown and increased p27 expression by Jab1-specific siRNA transfection. Jab1 silencing induced anti-proliferative and anti-migratory effects and resulted in G1 cell cycle arrest in SNU478 and HuCCT-1 cells. In addition, Jab1 silencing potentiated the anti-proliferative and anti-migratory effects of cisplatin by increasing DNA damage. Interestingly,Jab1 knockdown increased PTEN protein half-life, resulting in increased PTEN expression. In the HuCCT-1 mouse xenograft model, stable knockdown of Jab1 by shRNA also showed anti-proliferative effects in vivo, with decreased Ki-67 expression and AKT phosphorylation and increased Terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling and p27 expression. CONCLUSION: Jab1 knockdown demonstrated anti-proliferative and anti-migratory effects in BTC cells by increasing DNA damage and stabilizing PTEN, resulting in G1 cell cycle arrest. In addition, Jab1 silencing potentiated the anti-proliferative effects of cisplatin. Our data suggest that Jab1 may be a potential therapeutic target in BTC that is worthy of further investigations.

Effect of ABCG2 on Side Population Cells and Related Pathways in Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To investigate the biological characteristics of ABCG2 and its effect on side population cells (SP cells) of multiple myeloma (MM) so as to find the way for reversing drug resistance.@*METHODS@#The silence of ABCG2 expression was performed throngh interfering the MM cells by using siRNA. then the ratio of SP cell of MM, speed of cell proliferation and sensitivity of cells to chermotherapentic drugs before and after interference were compared, the biological functions of ABCG2 and its role in regulation of SP cells and PTEN/PI3K/AKT signaling pathway was clarified.@*RESULTS@#siRNA interference could down regulate the expression of ABCG2 at both mRNA and protein level. After siRNA interference, the proliferation of multiple myeloma cells was decreased slightly, the expression of PTEN was increased, the activity of PI3K/AKT pathway was inhibited, and the ratio of SP cells was decreased.@*CONCLUSION@#In multiple myeloma, down-regulation of expression ABCG2 can negatively regulate the expression of PTEN, the PI3K/AKT signaling pathway is inhibited,the ratio of SP decreased,and the response to drug is increased.

Bmi-1-siRNA Regulates the Proliferation of K562 Leukemia Cells in vitro and in vivo by PTEN/pAKT Pathway / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of Bmi-1 gene silence on the proliferation ability of K562 cells in vitro and in vivo, and to explore the relation of molecular mechanism between proliferation ability of K562 cells in vitro and in vivo with PTEN/pAKT signaling pathway.@*METHODS@#The Bmi-1 small interference RNA (siRNA) sequences were transfected into K562 cells for decreasing Bmi-1 expression. The effect of Bmi-1 siRNA on the proliferation of K562 cells in vitro and in vivo was detected by MTT method and colony-forming test, the effect of Bmi-1 siRNA on the tumorogenicity of K562 cells was observed by subcutaneous inoculation of K562 cells, LY294002 and Bpv treated K562 cells in nude mice, the expression of Bmi-1, PTEN and pAKT proteins were detected by Western blot.@*RESULTS@#The Bmi-1 siRNA could inhibit the proliferation activity, colony-forming and tumor-forming abilities of K562 cells. After the silence of Bmi-1 gene, the PTEN expression in Bmi-1 gene-silenced group was significantly enhanced. While the pAKT expression in Bmi-1 gene-silenced group was significantly reduced; after the K562 cells were treated with LY294002 (an inhibitor of pAKT), the pAKT expression colony-forming and tumor forming abilities were reduced in comparison with untreated K562 cells; after the K562-S1 cells were treated with Bpv (an inhibitor of PTEN), the PTEN expression decreased, while the pAKT expression, colony forming and tumor-forming abilities were restored.@*CONCLUSION@#The Bmi-1 gene possibly involves in regulation of K562 proliferation in vivo and in vitro, the effect of PTEN/pAKT signaling pathway maybe one of molecular mechanisms mediating this regulation.

Relationship of PTEN/PI3K/AKT Signaling Pathway Protein Expression with Apoptosis and Drug-resistance of Children's ALL Primary Cells Treated with Daunorubicin / 中国实验血液学杂志

OBJECTIVE@#To investigate the relationship of PTEN/PI3K/AKT signaling pathway protein expression with apoptosis and drug-resistance of children's ALL primary cells treated with daunorubicin (DNR).@*METHODS@#The bone marrow mononuclear cells in newly diagnosed and untreated B-ALL children were collected and cultured. After the treatment of primary-cultured cells with DNR of final concentration 0.5 mg/L for 24 h, the cell apoptosis rate was detected by using cell apoptosis assay kit; the samples were collected at the on test of culture and after drug treatment, then expression levels of PTEN, PI3K and AKT proteins were detected by Western blot, moreover the interindex correlation was analyzed.@*RESULTS@#After DNR treatment, the apoptosis rate in PTEN low expression group was lower than that in PTEN high expression group (P＜0.05), showing high positive correlation of the cell apoptosis rate with the expression of PTEN before DNR treatment; the cell apoptosis rate in PI3K and AKT low expression group was higher than that in PI3K and AKT high expression group (P＜0.01); however, the expression of PI3K and AKT proteins was down-regulated after treatment with DNR (P＜0.01).@*CONCLUSION@#The difference of PTEN expression is present in primary cells of B-ALL children, however the change of PTEN expression is not significant after DNR treatment, suggesting that the PTEN expression correlates with DNR-resistance. The DNR can induce the apoptosis of childrens B-ALL primary cells by down-regulating the expression of PI3K and AKT signaling pathway proteins.

Combination of biomaterial transplantation and genetic enhancement of intrinsic growth capacities to promote CNS axon regeneration after spinal cord injury / 医学前沿

The inhibitory environment that surrounds the lesion site and the lack of intrinsic regenerative capacity of the adult mammalian central nervous system (CNS) impede the regrowth of injured axons and thereby the reestablishment of neural circuits required for functional recovery after spinal cord injuries (SCI). To circumvent these barriers, biomaterial scaffolds are applied to bridge the lesion gaps for the regrowing axons to follow, and, often by combining stem cell transplantation, to enable the local environment in the growth-supportive direction. Manipulations, such as the modulation of PTEN/mTOR pathways, can also enhance intrinsic CNS axon regrowth after injury. Given the complex pathophysiology of SCI, combining biomaterial scaffolds and genetic manipulation may provide synergistic effects and promote maximal axonal regrowth. Future directions will primarily focus on the translatability of these approaches and promote therapeutic avenues toward the functional rehabilitation of patients with SCIs.