Antitumor activity of celastrol by inhibition of proliferation, invasion, and migration in cholangiocarcinoma via PTEN/PI3K/Akt pathway

AIM

Cholangiocarcinoma is a malignant tumor originating from bile duct epithelium. Currently, the treatment strategy is very limited and the prognosis is poor. Recent studies reported celastrol exhibits antigrowth and antimetastasis properties in many tumors. Our study aimed to assess the anti-CCA effects of cholangiocarcinoma (CCA) and the mechanisms involved in it.

METHODS

In this study, the long-term and short-term antiproliferation effects was determined using colony formation and Cell Counting Kit-8 (CCK-8) assays, respectively. Flow cytometry was performed to quantify apoptosis. Furthermore, wound healing and transwell assays were performed to determine the cell migration and invasion capabilities, respectively. To further find the mechanism involved in the celastrol-induced biological functions, LY204002, a PI3K/Akt signaling inhibitor, and an Akt-1 overexpression plasmid were employed to find whether PI3K/Akt pathway was involved in the celastrol-induced CCA cell inhibition. Additionally, short interfering RNA (siRNA) was also used to investigate the mechanism involved in the celastrol-induced PI3K/Akt signaling inhibition. Western blotting and immunofluorescence assays were also performed to detect the degree of relative proteins. Moreover, we validated the antiproliferation and antimetastasis effects of celastrol in vivo by constructing subcutaneous and lung metastasis nude mice models.

RESULTS

We discovered that celastrol effectively induced apoptotic cell death and inhibited the capacity of migration and invasion in CCA cells. Further mechanistic study identified that celastrol regulated the PI3K/Akt signaling pathway, and the antitumor efficacy was likely due to the upregulation of PTEN, a negative regulator of PI3K/Akt. Blockage of PTEN abolished the celastrol-induced PI3K/Akt signaling inhibition. Additionally, in vivo experiments conformed celastrol inhibited the tumor growth and lung metastasis with no serious side effects.

CONCLUSIONS

Overall, our study elucidated a mechanistic framework for the anti-CCA effects of celastrol via PTEN/PI3K/Akt pathway.

PTEN-knockdown disrupts the morphology, growth pattern and function of Nthy-Ori 3-1 cells by downregulating PAX8 expression

The incidence of thyroid disorders, which are common endocrine diseases, has rapidly increased in recent years. However, the etiology and pathogenesis of these disorders remain unclear. Phosphatase and tension homolog (PTEN) is a dual-specific phosphatase that is associated with multiple thyroid disorders; however, the role of PTEN in thyroid disorders remains unknown. In the present study, the human thyroid follicular epithelial cell line Nthy-Ori 3-1 was used to determine the role of PTEN in thyroid disorders. PTEN expression was knocked down using a PTEN-specific short hairpin RNA. Western blotting was subsequently used to determine protein expression, the Matrigel tube formation assay and iodide uptake assay were applied for evaluating the morphology and function of thyroid cells. The results showed that PTEN knockdown decreased the protein expression of paired box 8 (PAX8). The morphology and tubular-like growth pattern of thyroid cells were therefore disrupted, and restoration of PAX8 expression reversed these effects. Furthermore, PTEN-knockdown decreased the expression of specific thyroid proteins (thyroglobulin, TG; thyroid peroxidase, TPO; and sodium/iodide symporter, NIS) and inhibited the iodide uptake ability of thyroid cells by downregulating PAX8, suggesting that PTEN deficiency may impair the function of thyroid cells. In conclusion, the present study reported an important function of PTEN in normal thyroid cells and identified the involvement of PAX8. These results may improve understanding of the role of PTEN in the pathogenesis of thyroid disorders.

ΜicroRNA-221 participates in cerebral ischemic stroke by modulating endothelial cell function by regulating the PTEN/PI3K/AKT pathway

An effective method to improve the blood supply of brain tissue is by angiogenesis, which is crucial for the prognosis of patients with cerebral ischemic stroke (CIS). Therefore, angiogenesis has been a focus of CIS research in recent years. The present study aimed to investigate the expression of microRNA (miR)-221 in patients with CIS and to explore the effect of miR-221 on endothelial cell function. The level of miR-221 was detected using reverse transcription-quantitative PCR (RT-qPCR). The relationship between miR-221 and phosphatase and tensin homolog (PTEN) was predicted and confirmed by bioinformatics and dual luciferase reporter assay. Cell viability, migration and invasion, and cell apoptosis were determined using MTT assay, Transwell assay and flow cytometry respectively. Tube formation in human umbilical vein endothelial cells (HUVECs) was determined by performing the tube formation assay. In addition, protein levels were measured using western blot analysis. The results of the current study indicated that miR-221 levels were significantly decreased in the peripheral blood of patients with CIS. PTEN was confirmed to be a direct target of miR-221. Downregulation of miR-221 significantly inhibited the function of HUVECs as evidenced by the decreased cell viability, migration and invasion with increased cell apoptosis and tube formation inhibition. miR-221 upregulation produced the reverse effects, whilst all the effects of miR-221 upregulation on HUVECs were reversed by PTEN overexpression. The PI3K/AKT pathway was identified to be involved in the regulation of miR-221 on HUVECs. In conclusion, miR-221 was downregulated in CIS patients, and it promoted the function of HUVECs by regulating the PTEN/PI3K/AKT pathway in vitro, suggesting the ability to promote angiogenesis. Therefore, miR-221 may be a novel and promising therapeutic target for CIS treatment.

Augmenter of liver regeneration enhances cell proliferation through the microRNA-26a/Akt/cyclin D1 pathway in hepatic cells

AIM

Hepatocytes can proliferate and regenerate when injured by toxins, viral infections, and so on. Augmenter of liver regeneration (ALR) is a key regulator of liver regeneration, but the mechanism is unknown. The role of ALR in other cell types is not known. In the present study, we investigated the relationship between microRNA (miRNA)-26a and ALR in the Huh7 cell line and adipose tissue-derived mesenchymal cells from chronic liver disease patients and healthy individuals.

METHODS

Huh7 cells were transfected independently with ALR and miRNA-26a expression vectors, and their effects on cell proliferation, the expression of miRNA-26a, and activation of the phosphatase and tensin homolog and Akt signaling pathways were determined. The experiments were repeated on mesenchymal stem cells derived from healthy individuals and chronic liver disease patients to see whether the observations can be replicated in primary cells.

RESULTS

Overexpression of ALR or miRNA-26a resulted in an increase of the phosphorylation of Akt and cyclin D1 expression, whereas it resulted in decreased levels of p-GSK-3β and phosphatase and tensin homolog in Huh7 cells. The inhibition of ALR expression by ALR siRNA or anti-miR-26a decreased the Akt/cyclin D1 signaling pathway, leading to decreased proliferation. Mesenchymal stem cells isolated from the chronic liver disease patients had a higher ALR expression, while the mesenchymal stem cells isolated from healthy volunteers responded to the growth factor treatments for increased ALR expression. It was found that there was a significant increase in miRNA-26a expression and proliferation.

CONCLUSIONS

These data clearly showed that ALR induced the expression of miRNA-26a, which downregulated phosphatase and tensin homolog, resulting in an increased p-Akt/cyclin D1 pathway and enhanced proliferation in hepatic cells.

Nuclear miR-665 aggravates heart failure via suppressing phosphatase and tensin homolog transcription

Although numerous miRNAs have been discovered, their functions in the different subcellular organelles have remained obscure. In this study, we found that miR-665 was enriched in the nucleus of cardiomyocytes, and then investigated the underlying role of nuclear miR-665 in heart failure. RNA fluorescence in situ hybridization assays in human heart tissue sections and primary cardiomyocytes showed that miR-665 was localized in the nucleus of cardiomyocytes. Increased expression of nuclear miR-665 was observed not only in the cardiomyocytes isolated from the heart of mice treated in vivo by transverse aortic constriction (TAC), but also in phenylephrine (PE)-treated cultured cardiomyocytes in vitro. To further explore the role of miR-665 in heart failure, a type 9 recombinant adeno-associated virus (rAAV) system was employed to manipulate the expression of miR-665 in mice. Overexpression of miR-665 aggravated TAC-induced cardiac dysfunction, while down-expression of miR-665 showed opposite effects. Bioinformatic prediction and biological validation confirmed that the PTEN (phosphatase and tensin homolog) gene was one of the targets of miR-665 in the nucleus. Furthermore, restoring PTEN expression significantly eliminated the destructive effects of miR-665 over-expression in TAC-induced cardiac dysfunction. Our data showed that nuclear miR-665 aggravates heart failure via inhibiting PTEN expression, which provided a therapeutic approach for heart failure.

Effect and mechanism of microRNA-10b on proliferation and invasion of esophageal cancer cells

MicroRNA (miR)-10b is highly expressed in esophageal cancer tissues and is associated with poor prognosis of esophageal cancer. However, the role and mechanism of miR-10b in esophageal cancer cells remains unclear, therefore, the present study aimed to investigate this. Esophageal cancer cells, TE-1 and EC9706, were transfected with miR-10b mimic, miR-10b inhibitor or incubated with transforming growth factor-β (TGF-β). MTT and EdU assays were used to detect cell proliferation. Flow cytometry was used to determine cell cycle analysis and apoptosis. Cell migration and invasion were also analyzed. Western blot analysis was used to detect protein levels and reverse transcription-quantitative PCR was used to analyze miR-10b expression. The present results demonstrated that, compared with the control group, miR-10b significantly promoted TE-1 and EC9706 cell proliferation. Compared with miR-10b inhibitor group and control group, miR-10b mimic promoted esophageal cancer cell cycle progression, inhibited apoptosis of esophageal cancer cells and promoted the migration and invasion of cells. The proliferation of esophageal cancer cells increased in a dose-dependent manner with TGF-β concentration. TGF-β treatment induced high expression of miR-10b in both cell lines. The miR-10b mimic + TGF-β group further promoted the migration and invasion of esophageal cancer cells. Western blot analysis determined that, compared with the control group, miR-10b mimic increased TGF-β expression. miR-10b mimic also inhibited the expression of phosphatase and tensin homolog (PTEN) in tumor cells. Compared with the control group, TGF-β inhibited the expression of PTEN with the miR-10b mimic + TGF-β group further inhibiting the PTEN. miR-10b inhibitor + TGF-β reversed the effect of TGF-β and miR-10b on PTEN. In conclusion, miR-10b promoted cell cycle progression, inhibited apoptosis and promoted the migration and invasion of esophageal cancer cells. The mechanism may be related to the upregulation of TGF-β and the downregulation of PTEN. The present findings suggested that miR-10b might be a potential therapeutic target for esophageal cancer.

Study of the Association of Phosphatase and Tensin Homolog and p27 Expressions in Endometrial Hyperplasia and Carcinoma

Introduction:

Phosphatase and tensin homolog (PTEN) and p27 are commonly mutated gene in endometrial carcinoma (EC) and their association in development of EC has not been fully understood.

The Aim of the Study:

The aim is to clarify the association of PTEN and p27 in EC and their correlation with the histologic grade.

Material and Methods:

Paraffin-embedded 20 and 50 specimens representing EH and EC were collected, cut into 4 mm thick and stained with H&E stain for histopathological examination. All EC cases were graded according to the percentage of nonsquamous solid pattern into 3 grades. Immunohistochemical (IHC) analyses were done using a rabbit polyclonal anti-PTEN antibody and a rabbit monoclonal anti-p27 antibody. Evaluation of reactivity was categorized: 1+ (weak) = less than 10%, 2+ (moderate) = 11 to 50% and 3+ (strong) = more than 50% tumor. t-test, one way ANOVA and chi-square test were used in the statistical analysis.

Results:

Loss of PTEN was seen in 7/20 (35%) and 29/50 (58%) of EH and EC cases with significance (P =0.01824), opposite to 17/20 (85%) and 25/50 (50%) of p27 (P = 0.00334). Both antibodies showed significance in EH cases only (P = 0.00019). No correlation with the histological grade for both antibodies. Four major categories were formulated; PTEN+/p27+ (n = 2, 14, 10%, 28%), PTEN+/p27- (n = 5, 7; 25% and 14%), PTEN-/p27+ (n = 1, 11; 5%, 22%) PTEN-/p27- (n = 12, 18; 60%, 36%) cases of EH and EC, respectively with no significant difference obtained.

Conclusion:

Not all cases of PTEN negative EC showing p27 loss and vice versa. Despite many studies reacted with PTEN and p27 expression in EC, none of them is confirmatory to adjust the correlation between them in EC. So, more studies must be done to correlate between the degree of PTEN loss and p27 comprising all subtypes and grading of EC.

Everolimus inhibits the proliferation and migration of epidermal growth factor receptor-resistant lung cancer cells A549 via regulating the microRNA-4328/phosphatase and tensin homolog signaling pathway

Lung cancer is the most common cancer type worldwide, and investigating novel therapeutics methods for the treatment of chemoresistant lung cancer are of notable clinical significance. Reverse transcription-quantitative polymerase chain reaction and western blotting assays were performed to analyze the expression levels of phosphatase and tensin homolog (PTEN) and microRNA-4328 (miR-4328), and Cell Counting Kit-8 (CCK-8) and Transwell migration assays were conducted to evaluate the proliferation and migration of A549 cells, respectively. Everolimus was observed to upregulate the expression of PTEN and inhibit the proliferation and migration of A549 cells in a dose-dependent manner. The knockdown of PTEN abolished the effects of everolimus on the proliferation and migration of A549 cells, and everolimus was demonstrated to upregulate PTEN, and inhibit the proliferation and migration of A549 cells via downregulating miR-4328. Collectively, the results of the present study indicate that everolimus inhibited the proliferation and migration of EGFR-resistant A549 lung cancer cells via regulating the miR-4328/PTEN signaling pathway.

MicroRNA-34a inhibits bladder cancer cell migration and invasion, and upregulates PTEN expression

MicroRNA-34a (miR-34a) serves as a tumor suppressor in a number of different types of cancer. The present study was performed to investigate the involvement of miR-34a in bladder cancer. In the present study, miR-34a was downregulated in patients with bladder cancer compared with the healthy controls in bladder biopsies and plasma. Downregulation of miR-34a distinguished between patients with bladder cancer and the healthy controls. miR-34a expression was associated with tumor metastasis; however, not with tumor size. Transfection of miR-34a mimics upregulated the expression of phosphatase and tensin homolog (PTEN) in bladder cancer cells, and decreased cell migration and invasion. miR-34a may inhibit bladder cancer cell migration and invasion by upregulating PTEN. miR-34a may additionally serve as a potential therapeutic target for bladder cancer.

miR-20a-5p regulates pulmonary surfactant gene expression in alveolar type II cells

MicroRNA (miRNA) critically controls gene expression in many biological processes, including lung growth and pulmonary surfactant biosynthesis. The present study was conducted to investigate whether miR‐20a‐5p had such regulatory functions on alveolar type II (AT‐II) cells. To accomplish this, miR‐20a‐5p–overexpressed and miR‐20a‐5p–inhibited adenoviral vectors were constructed and transfected into cultured AT‐II cells that were isolated from rat foetal lungs of 19 days' gestation. Transfection efficiency was confirmed by observing the fluorescence of green fluorescent protein (GFP) carried by the viral vector, whereas miR‐20a‐5p levels were verified by real‐time PCR. The CCK‐8 assay was used to compare the proliferation ability of AT‐II cells that had over‐ or underexpressed miR‐20a‐5p. The expression of surfactant‐associated proteins (SPs) and phosphatase and tensin homolog (PTEN) was measured by real‐time PCR and Western blotting. In AT‐II cells, transfection resulted in over‐ or under‐regulation of miR‐20a‐5p. While overexpression of miR‐20a‐5p promoted pulmonary surfactant gene expression, its underexpression inhibited it. Consistent with its role in negatively regulating the pulmonary surfactant gene, an opposite pattern was observed for miR‐20a‐5p regulation of PTEN. As a result, when miR‐20a‐5p was rendered overexpressed, PTEN was down‐regulated. By contrast, when miR‐20a‐5p was underexpressed, PTEN was up‐regulated. Neither overexpression nor underexpression of miR‐20a‐5p altered the cell proliferation. miR‐20a‐5p plays no role in proliferation of foetal AT‐II cells but is a critical regulator of surfactant gene expression. The latter appears to be achieved through a regulatory process that implicates expression of PTEN.

Effect of HIF-1α/miR-10b-5p/PTEN on Hypoxia-Induced Cardiomyocyte Apoptosis

Background Few reports have addressed the mechanism by which microRNA miR-10b-5p regulates post-myocardial infarction (post-MI) cardiomyocyte apoptosis under hypoxic conditions. Methods and Results C57BL/6 mice underwent surgical ligation of the left anterior descending artery to create an MI or ischemia/reperfusion animal model. The expression of miR-10b-5p, PTEN (phosphatase and tensin homolog), and HIF-1α (hypoxia-inducible factor 1α) was detected in infarct border zone tissues at various time points. After precordial injections of the negative control or miR-10b-5p, overexpression lentiviruses were made in the areas surrounding the MI sites at 1 week, and myocardial infarct size, cardiac function, and cardiomyocyte apoptosis were examined. A miR-10b-5p mimic was transfected into primary mouse cardiomyocytes to analyze its effects on cardiomyocyte apoptosis and PTEN expression. Meanwhile, PTEN as a target of miR-10b-5p was verified via luciferase reporter gene assays. Cotransfection of miR-10b-5 and PTEN verified the relationship between miR-10b-5 and PTEN. Under hypoxic stress, the expression of HIF-1α and miR-10b-5p was examined. The results showed that miR-10b-5p expression was markedly reduced in the infarct border zone. Overexpression of miR-10b-5p in the murine model of MI significantly reduced MI size, improved cardiac function, and inhibited apoptosis. Overexpression of miR-10b-5p in vitro antagonized hypoxia-induced cardiomyocyte apoptosis and specifically inhibited the expression of the apoptosis-related gene PTEN, but overexpression of PTEN weakened these effects. We also found that hypoxia-induced accumulation of HIF-1α resulted in decreased expression of miR-10b-5p. Interfering with the activation of the HIF-1α signaling pathway promoted Pri-miR-10b and miR-10b-5p expression and inhibited PTEN expression. Conclusions MicroRNA miR-10b-5p antagonizes hypoxia-induced cardiomyocyte apoptosis, indicating that miR-10b-5p may serve as a potential future clinical target for the treatment of MI.

Long non-coding RNA cardiac hypertrophy-associated regulator governs cardiac hypertrophy via regulating miR-20b and the downstream PTEN/AKT pathway

Pathological cardiac hypertrophy (CH) is a key factor leading to heart failure and ultimately sudden death. Long non‐coding RNAs (lncRNAs) are emerging as a new player in gene regulation relevant to a wide spectrum of human disease including cardiac disorders. Here, we characterize the role of a specific lncRNA named cardiac hypertrophy‐associated regulator (CHAR) in CH and delineate the underlying signalling pathway. CHAR was found markedly down‐regulated in both in vivo mouse model of cardiac hypertrophy induced by pressure overload and in vitro cellular model of cardiomyocyte hypertrophy induced by angiotensin II (AngII) insult. CHAR down‐regulation alone was sufficient to induce hypertrophic phenotypes in healthy mice and neonatal rat ventricular cells (NRVCs). Overexpression of CHAR reduced the hypertrophic responses. CHAR was found to act as a competitive endogenous RNA (ceRNA) to down‐regulate miR‐20b that we established as a pro‐hypertrophic miRNA. We experimentally established phosphatase and tensin homolog (PTEN), an anti‐hypertrophic signalling molecule, as a target gene for miR‐20b. We found that miR‐20b induced CH by directly repressing PTEN expression and indirectly increasing AKT activity. Moreover, CHAR overexpression mitigated the repression of PTEN and activation of AKT by miR‐20b, and as such, it abrogated the deleterious effects of miR‐20b on CH. Collectively, this study characterized a new lncRNA CHAR and unravelled a new pro‐hypertrophic signalling pathway: lncRNA‐CHAR/miR‐20b/PTEN/AKT. The findings therefore should improve our understanding of the cellular functionality and pathophysiological role of lncRNAs in the heart.

Ligand-independent activation of the P2X7 receptor by Hsp90 inhibition stimulates motor neuron apoptosis

Activation of the extracellular ATP ionotropic receptor P2X7 stimulates motor neuron apoptosis, whereas its inhibition in cell and animal models of amyotrophic lateral sclerosis can be protective. These observations suggest that P2X7 receptor activation is relevant to motor neuron disease and that it could be targeted for therapeutic development. Heat shock protein 90 (Hsp90) is an integral regulatory component of the P2X7 receptor complex, antagonizing ligand-induced receptor activation. Here, we show that the repressive activity of Hsp90 on P2X7 receptor activation in primary motor neurons is highly sensitive to inhibition. Primary motor neurons in culture are 100-fold more sensitive to Hsp90 inhibition by geldanamycin than other neuronal populations. Pharmacological inhibition and down-regulation of the P2X7 receptor prevented motor neuron apoptosis triggered by Hsp90 inhibition, which occurred in the absence of extracellular ATP. These observations suggest that inhibition of a seemingly motor neuron specific pool of Hsp90 leads to ligand independent activation of P2X7 receptor and motor neuron death. Downstream of Hsp90 inhibition, P2X7 receptor activated the phosphatase and tensin homolog (TPEN), which in turn suppressed the pro-survival phosphatidyl inositol 3 kinase (PI3K)/Akt pathway, leading to Fas-dependent motor neuron apoptosis. Conditions altering the interaction between P2X7 receptor and Hsp90, such as recruitment of Hsp90 to other subcellular compartments under stress conditions, or nitration following oxidative stress can induce motor neuron death. These findings may have broad implications in neurodegenerative disorders, including amyotrophic lateral sclerosis, in which activation of P2X7 receptor may be involved in both autonomous and non-autonomous motor neurons death.

Aberrant expression and mechanism of miR-130b-3p/phosphatase and tensin homolog in nephroblastoma in children

Nephroblastoma is the most common renal tumor in children. Abnormal expression of microRNAs (miRs) has been reported to be involved in the progression of various types of cancers. However, the role and underlying mechanism of miR-130b-3p in nephroblastoma remains unknown. Therefore, the present study aimed to explore the role and possible mechanism of miR-130b-3p in nephroblastoma in children. The present study identified that miR-130b-3p was highly expressed in nephroblastoma tissues obtained from children with nephroblastoma. To better understand the functions and the molecular mechanisms of miR-130b-3p in nephroblastoma, TargetScan was used to identify the potential targets of miR-130b-3p. Phosphatase and tensin homolog (PTEN), was identified as a target gene of miR-130b-3p, and it was observed to be downregulated in nephroblastoma. Further analysis indicated that miR-130b-3p inhibitor could significantly reduce cell proliferation, induce apoptosis and suppress the Akt/nuclear factor-κB/survivin signaling pathway in nephroblastoma cells. Notably, all these effects of miR-130b-3p on nephroblastoma cells were reversed by PTEN-small interfering RNA. In summary, the present study suggested that the miR-130b-3p/PTEN axis could serve a critical role in the progression and development of nephroblastoma. It also suggests that miR-130b-3p might be a valuable clinical biomarker and therapeutic target for nephroblastoma in children.

Overexpression of UBR5 promotes tumor growth in gallbladder cancer via PTEN/PI3K/Akt signal pathway

As a key regulator of the ubiquitin-proteasome system, ubiquitin protein ligase E3 component N-recognin 5 (UBR5) plays an important role in various cancers. In this study, our results showed for the first time that UBR5 was overexpressed in gallbladder cancer (GBC) tumor tissues. UBR5 overexpression was significantly associated with tumor size, histological and tumor differentiation. UBR5 overexpression was also associated with poor prognosis in patients with GBC. The knockdown of UBR5 remarkably inhibited the cell proliferation and colony formation of GBC-Shandong (SD) cells in vitro and in vivo. UBR5 potentially increases the level of protein kinase B phosphorylation via the degradation of phosphatase and tensin homolog, which contributes to tumor growth in GBC. UBR5 may be an important biomarker for predicting the prognosis of patients with GBC.

Activation of the oncogenic miR-21-5p promotes HCV replication and steatosis induced by the viral core 3a protein

BACKGROUND & AIMS

miR-21-5p is a potent oncogenic microRNA targeting many key tumour suppressors including phosphatase and tensin homolog (PTEN). We recently identified PTEN as a key factor modulated by hepatitis C virus (HCV) to promote virion egress. In hepatocytes, expression of HCV-3a core protein was sufficient to downregulate PTEN and to trigger lipid droplet accumulation. Here, we investigated whether HCV controls PTEN expression through miR-21-5p-dependent mechanisms to trigger steatosis in hepatocytes and to promote HCV life cycle.

METHODS

MiR-21-5p expression in HCV-infected patients was evaluated by transcriptome meta-analysis. HCV replication and viral particle production were investigated in Jc1-infected Huh-7 cells after miR-21-5p inhibition. PTEN expression and steatosis were assessed in HCV-3a core protein-expressing Huh-7 cells and in mouse primary hepatocytes having miR-21-5p inhibited or genetically deleted respectively. HCV-3a core-induced steatosis was assessed in vivo in Mir21a knockout mice.

RESULTS

MiR-21-5p expression was significantly increased in hepatic tissues from HCV-infected patients. Infection by HCV-Jc1, or transduction with HCV-3a core, upregulated miR-21-5p expression and/or activity in Huh-7 cells. miR-21-5p inhibition decreased HCV replication and release of infectious virions by Huh-7 cells. HCV-3a core-induced PTEN downregulation and steatosis were further prevented in Huh-7 cells following miR-21-5p inhibition or in Mir21a knockout mouse primary hepatocytes. Finally, steatosis induction by AAV8-mediated HCV-3a core expression was reduced in vivo in Mir21a knockout mice.

CONCLUSION

MiR-21-5p activation by HCV is a key molecular step, promoting both HCV life cycle and HCV-3a core-induced steatosis and may be among the molecular changes induced by HCV-3a to promote carcinogenesis.

Rosiglitazone prevents acute pancreatitis through inhibiting microRNA-26a expression

The aim of the present study was to investigate the regulatory effect of rosiglitazone on the progression of acute pancreatitis (AP) and pancreas injury, and the underlying mechanism. An AP rat model was established using caerulein and validated by detection of amylase, lipase, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and transforming growth factor-β (TGF-β) serum levels. Pancreatic injury was assessed by pathological examination. The expression levels of microRNA (miR)-26a in AP rats and AR42J cells were analyzed using reverse transcription-quantitative PCR (RT-qPCR). Luciferase reporter gene assay was applied for detecting whether miR-26a bound to the target gene phosphatase and tensin homolog (PTEN). The regulatory effect of rosiglitazone on the PI3K/AKT signaling pathway was analyzed by western blot analysis. Results demonstrated that establishment of an AP model was successful with severe pancreas injury and classic AP phenotypes observed in rats. Increased serum expression of amylase, lipase, TNF-α, IL-6 and TGF-β were observed in AP rats. Rosiglitazone pretreatment prevented AP progression through suppression of miR-26a expression via binding to and degrading PTEN. Western blot analysis demonstrated that rosiglitazone blocked the PI3K/AKT signaling pathway through PTEN. In conclusion, it was determined that rosiglitazone prevented AP by downregulating miR-26a via the PI3K/AKT signaling pathway.

SHCBP1 regulates apoptosis in lung cancer cells through phosphatase and tensin homolog

Src homologous and collagen (SHC) SH2-binding protein 1 (SHCBP1) is a member of the SHC family, and is overexpressed in numerous types of cancer. In addition, apoptosis serves an important role in the development of cancer. The purpose of this study was to examine the effect of SHCBP1 on apoptosis and its potential underlying mechanism in lung cancer cells. Apoptosis was detected by flow cytometry and caspase-3 activity analysis. The expression levels of SHCBP1 and phosphatase and tensin homolog (PTEN) were detected by western blot analysis and reverse transcription-quantitative polymerase chain reaction. Cell viability was determined by MTT assay. The results indicated that SHCBP1 was increased in lung cancer cell lines and lung cancer tissues compared with in normal lung cell lines and tissues. The apoptosis of lung cancer cells was significantly increased by SHCBP1 small interfering RNA (siRNA), as indicated by the increased number of apoptotic cells and enhanced caspase-3 activity. In addition, it was demonstrated that PTEN expression was modulated by SHCBP1 knockdown; silencing of SHCBP1 expression led to a significant increase in PTEN expression. Furthermore, inhibition of PTEN by siRNA reversed the increase in apoptosis induced by SHCBP1 siRNA. These results suggested that SHCBP1 may be upregulated in lung cancer and it may serve a key role in the apoptosis of lung cancer cells; this effect was associated with the expression of PTEN.

Inhibition of microRNA-103 attenuates inflammation and endoplasmic reticulum stress in atherosclerosis through disrupting the PTEN-mediated MAPK signaling

Atherosclerosis (AS), a chronic disorder of large arteries, is the underlying pathological process of heart disease and stroke. Former researchers have found that microRNAs (miRs) are involved in the several key processes of AS. Apolipoprotein E knockout (ApoE^-/- ) mice fed a high-fat-diet (HFD) to establish AS model. The expression of miR-103 was characterized in the mice model. The effects of miR-103 on inflammation and endoplasmic reticulum stress (ERS) were analyzed when the expression of miR-103 was inhibited in ApoE ^-/- mice fed an HFD and human aortic endothelial cells (HAECs) exposed to oxidized low-density lipoprotein (ox-LDL). The relationship between miR-103 and phosphatase and tensin homolog (PTEN) was identified by luciferase activity detection and real-time quantitative polymerase chain reaction (RT-qPCR). Gain- and loss-function approaches were further applied for investigating the regulatory effects of miR-103 and PTEN on ERS. Role of MAPK signaling was then analyzed using PD98059 to block this pathway. miR-103 was highly expressed in the ApoEApoE ^-/- mice fed an HFD. Downregulation of miR-103 suppressed inflammation and ERS in endothelial cells isolated from ApoE ^-/- mice fed a HFD and ox-LDL-exposed HAECs. In addition, miR-103 can target PTEN and downregulate its expression. Overexpression of PTEN reversed the miR-103-induced activation of MAPK signaling. Moreover, PTEN upregulation or MAPK signaling inhibition ease miR-103-induced inflammation and ERS in vivo and in vitro. Thus, miR-103 depletion restrains the progression of AS through blocking PTEN-mediated MAPK signaling.

ILF2 promotes anchorage independence through direct regulation of PTEN

Anoikis is a specific form of programmed cell death induced by loss of contact between cells and extracellular matrices or other cells. Only tumor cells that are resistant to anoikis can survive in the state of detachment from the primary tissue during the early stages of metastasis. The ability to resist anoikis is crucial for cancer cell metastasis. ILF2 is a proto-oncogene previously studied in glioma, NSCLC, esophageal cancer and pancreatic ductal carcinoma. The results from the present study revealed that the transcription factor interleukin enhancer-binding factor 2 (ILF2) was highly expressed in non-small cell lung cancer (NSCLC) cell lines compared with in normal cell lines. ChIP and luciferase reporter gene assays demonstrated that ILF2 inhibited the expression level of the tumor suppressor gene phosphatase and tensin homolog (PTEN) by directly binding to its upstream regulatory region. Furthermore, the results from the detection of cell adhesion and apoptosis in cell suspension culture demonstrated that this mechanism enabled NSCLC cells to reduce adherence to the matrix and to survive in this abnormal state. These results suggested that ILF2 may promote the anchorage-independence of NSCLC cells through the suppression of PTEN.

Promotion of PTEN on apoptosis through PI3K/Akt signal in vascular smooth muscle cells of mice model of coronary heart disease

Previous studies have shown that phosphatase and tensin homolog (PTEN) are key regulators of the development of many malignant tumors and other diseases. However, its regulatory effect on coronary heart disease (CHD) has rarely been reported. Therefore, the regulatory effect of PTEN on the survival and cell death of vascular smooth muscle cells (VSMCs) in CHD mice was elucidated in this study. It was found that the protein and messenger RNA expressions of PTEN in VSMCs of 10 CHD mice were lower than those of normal mice. Then PTEN was overexpressed in VSMCs. It was suggested that the upregulation of PTEN was not conducive to the proliferation and survival of VSMCs in the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony formation assay. The flow cytometry (Annexin V-Fluorescein isothiocyanate (FITC)/propidium iodide) and the terminal deoxynucleotidyl transferase dUTP nick end labeling assay were used to detect the apoptotic rate of overexpressing PTEN cells. Some data showed that the expression of PTEN could lead to increased apoptotic rate. It was shown that antiapoptotic Bcl-2 levels were decreased, but cleaved caspase-3 and proapoptotic Bax levels were promoted by SIRT6 overexpression in Western blot analysis. Moreover, PI3K/Akt expression and phosphorylation were significantly decreased in cells expressing PTEN. Recovery of PI3K expression inhibited the suppressive influence of PTEN on VSMC survival, as evidenced by the activated PI3K/Akt pathway, increased cell proliferative rate, reduced the apoptotic level, and reversed expression patterns of Bcl-2 and Bax. Therefore, the findings in this study provide a new idea on the occurrence and development mechanism of CHD and may promote the discovery of innovative therapies.

Assessment of epigenetic alterations and in silico analysis of mutation affecting PTEN expression among Indian cervical cancer patients

Genetic and epigenetic anomalies accountable for genetic dysregulation are the most common aberrations that determine the underlying heterogeneity of the tumor cells. Currently, phosphatase and tensin homolog (PTEN) incongruity has emerged as potent and persuasive malfunctioning in varied human malignancies. In this study, we have analysed the promoter hypermethylation and expression status of PTEN. We identified different mutations in the exonic region of PTEN. Functional consequences of these mutations were explored using in silico techniques. Promoter hypermethylation of PTEN was detected using methylation-specific polymerase chain reaction (MS-PCR), expression analysis was performed with immunohistochemistry (IHC) and mutation by direct sequencing in a total of 168 uterine cervix tumor cases. The findings were statistically correlated with the clinical parameters. In addition, the effect of nonsynonymous mutations was studied with molecular dynamics simulations. PTEN promoter hypermethylation (45.8%) was found to be significantly associated with the of PTEN loss (57.14%, P < 0.0001). Tumor stages, tumor size, lymph node (LN) were found to be significantly correlated with both PTEN promoter hypermethylation and PTEN loss. Histological grade, however, showed a significant association with only PTEN loss. In total, 11.76% of tumors exhibited mutations in exon 5 and 7, out of which E150K of exon 5 showed the highest deviations in the crystal structure of PTEN by in silico analysis. This study provides valuable insights into oncology and paves the path in the development of efficient biomarker and/or imperative therapeutic tool for cervical cancer treatment.

miR-188-5p emerges as an oncomiRNA to promote gastric cancer cell proliferation and migration via upregulation of SALL4

MicroRNAs (miRNAs) play pivotal roles in modulating key biological processes in gastric cancer (GC). As a newly identified miRNA, the function and potential mechanism of miR-188-5p in GC has not been thoroughly elucidated. Here, quantitative real-time polymerase chain reaction detection showed abnormally higher expression of miR-188-5p in GC cells and tissues. Gain-of-function analysis in vitro showed that miR-188-5p promoted GC cell proliferation and migration, while loss-of-function studies showed the reverse. Targetscan has predicted that phosphatase and tensin homolog (PTEN) was a potential target gene of miR-188-5p. miR-188-5p suppressed PTEN messenger RNA and protein expression and activated downstream AKT/mTOR signaling in GC cells, but luciferase reporter analysis showed that PTEN was not regulated by miR-188-5p via the 3' untranslated region. Furthermore, we observed that miR-188-5p overexpression promoted Sal-like protein 4 (SALL4) protein expression, cellular nuclear translocation, and transcription. Knockdown of SALL4 eliminated the effect of miR-188-5p in GC cells as well as suppression of PTEN. Taken together, our results demonstrate that miR-188-5p promotes GC cell proliferation and migration while suppressing tumor suppressor gene PTEN expression via transcriptional upregulation of oncogene SALL4. We conclude that miR-188-5p acts as an oncomiRNA in GC and may be a promising therapeutic target for GC.

The Antioxidant from Ethanolic Extract of Rosa cymosa Fruits Activates Phosphatase and Tensin Homolog In Vitro and In Vivo: A New Insight on Its Antileukemic Effect

Rosa cymosa Tratt is a Chinese herbal remedy that is used in the treatment of diarrhea, burns, rheumatoid arthritis, and hemorrhage. Despite its use in Asian folk medicine, there are limited reports on the biological activity of R. cymosa fruits. This study focused on the investigation of the antitumor effect of the antioxidative ethanolic extract of R. cymosa fruits (RCE) along with its underlying mechanism of action. RCE showed a potent cytotoxic effect against Sup-T1 and Molt-4 lymphoblastic leukemia cells. In the xenograft animal model, the tumor size was significantly reduced to about 59.42% in the RCE-treated group in comparison with the control group. The use of RCE (37.5, 75, or 150 μg/mL) triggered apoptosis by 26.52–83.49%, disrupted mitochondrial membrane potential (MMP) by 10.44–58.60%, and promoted calcium release by 1.29-, 1.44-, and 1.71-fold compared with the control group. The extract induced redox oxygen species (ROS) generation through the elimination of Nrf2/Keap1/P62-mediated oxidative stress response. The loss of phosphatase and tensin homolog (PTEN) activation by RCE impaired PI3K/Akt/Foxo and Jak/Stat activation pathways, which contributed to tumorigenesis. These multiple targets of R. cymosa against hematologic cancer cells suggested its potential application as an antileukemic dietary supplement.

Expression of p53 and PTEN in human primary endometrial carcinomas: Clinicopathological and immunohistochemical analysis and study of their concomitant expression

Endometrial carcinoma is a common malignancy of the female genital tract. Alterations in the expression levels of various oncogenes and tumor suppressor genes serve important roles in the carcinogenesis and biological behavior of endometrial carcinoma. The aim of the present study was to evaluate the combination and individual expression of p53 and phosphatase and tensin homolog (PTEN) protein in human endometrial carcinoma. In addition, the correlation of these proteins with clinicopathological parameters was also assessed. Retrospective immunohistochemical analysis of the expression of p53 and PTEN tumor suppressor proteins was conducted in 99 women with endometrial carcinoma. The overall rate of p53 and PTEN positivity was 89 and 77%, respectively, according to the sum of stain intensity and scores of immunopositive cells. The sum of p53 positivity correlated strongly with PTEN expression (ρ=0.256; P=0.044). The concomitant sum of p53 and PTEN expression was identified in 45% of patients with endometrial adenocarcinoma. Notably, the sum of the immunohistochemical expression of p53 was significantly correlated with patient age (P=0.037), histologic type (P=0.008), histologic grade (P=0.002) and fallopian and/or ovarian invasion (P=0.014). Furthermore, PTEN expression was associated with myometrial invasion (ρ=−0.377; P=0.002) and clinical stage (P=0.019). In addition, concomitant p53 and PTEN expression was correlated with patient age (P=0.008) and histologic differentiation (P=0.028). The findings indicated a correlation between the expression of p53 and PTEN in endometrial adenocarcinoma, which suggested an intrinsic association between expression levels of these tumor suppressor genes. The study also suggested that concomitant p53 and PTEN expression contributed in characterizing the tumor behavior of endometrial carcinoma. Taken together, the present study suggested the combined expression of p53 and PTEN in the development of high-grade endometrial carcinoma in older patients. In addition, the findings indicated activation of different molecular pathways in the tumor progression between low-grade and high-grade endometrial carcinomas.

Retracted: Upregulated microRNA-132 rescues cardiac fibrosis and restores cardiocyte proliferation in dilated cardiomyopathy through the phosphatase and tensin homolog-mediated PI3K/Akt signal transduction pathway

Cardiac fibrosis is known to be present in dilated cardiomyopathy (DCM) and it predicts the occurrence of sudden death and congestive heart failure. The aim of our study is to investigate the expression of microRNA-132 (miR-132) and its effect on cardiocyte proliferation, apoptosis, and cardiac fibrosis by binding to phosphatase and tensin homolog (PTEN) through the phosphateidylinositol 3-kinase (PI3K)/protein kinase (Akt) signal transduction pathway in DCM rats. DCM rat models induced by doxorubicin were established and confirmed by an ultrasonic cardiogram. Epithelial cells were treated with inhibitors, activators, and small interfering RNAs to identify the mechanisms by which miR-132 controls cardiocyte activity and cardiac fibrosis. Angiotensin II (Ang II) and aldosterone (ALD) expressions were detected by an enzyme-linked immunosorbent assay. The relationship between PTEN and miR-132 was verified by a dual-luciferase reporter assay. Cell proliferation and apoptosis were tested by the MTT assay and flow cytometry. PTEN was determined to be the target gene of miR-132. Rat models of DCM exhibited a lower level of miR-132, PI3K, Akt, B-cell lymphoma 2, collagen I, and collagen III, but a higher level of PTEN, Bcl-2-associated X protein, and proliferating cell nuclear antigen as well as inflammatory response (Ang II and ALD), accompanied by declined cardiocyte proliferation and elevated apoptosis and cardiac fibrosis. Upregulated miR-132 or silenced PTEN activated the PI3K/Akt pathway, thus facilitating cardiocyte proliferation and repressing cardiocyte apoptosis and cardiac fibrosis, as well as inflammatory responses. Downregulated miR-132 reversed this tendency. These findings indicate that miR-132 activates the PI3K/Akt pathway by inhibiting PTEN expression, thus facilitating cardiocyte proliferation and inhibiting apoptosis and cardiac fibrosis in DCM rats.

ERBB2 and PTPN2 gene copy numbers as prognostic factors in HER2-positive metastatic breast cancer treated with trastuzumab

Trastuzumab has markedly improved the treatment and long-term prognosis of patients with HER2-positive breast cancer. A frequent clinical challenge in patients with relapsing and/or metastatic disease is de novo or acquired trastuzumab resistance, and to date no predictive biomarkers for palliative trastuzumab have been established. In the present study, the prognostic values of factors involved in the HER2-associated PI3K/Akt signalling pathway were explored. The first 46 consecutive patients treated at the Department of Oncology, Linköping University Hospital between 2000 and 2007 with trastuzumab for HER2-positive metastatic breast cancer were retrospectively included. The gene copy number variation and protein expression of several components of the PI3K/Akt pathway were assessed in the tumour tissue and biopsy samples using droplet digital polymerase chain reaction and immunohistochemistry. Patients with tumours displaying a high-grade ERBB2 (HER2) amplification level of ≥6 copies had a significantly improved overall survival hazard ratio [(HR)=0.4; 95%, confidence interval (CI): 0.2–0.9] and progression-free survival (HR=0.3; 95% CI: 0.1–0.7) compared with patients with tumours harbouring fewer ERBB2 copies. High-grade ERBB2 amplification was significantly associated with the development of central nervous system metastases during palliative treatment. Copy gain (≥3 copies) of the gene encoding the tyrosine phosphatase PTPN2 was associated with a shorter overall survival (HR=2.0; 95% CI: 1.0–4.0) and shorter progression-free survival (HR=2.1; 95% CI: 1.0–4.1). In conclusion, high ERBB2 amplification level is a potential positive prognostic factor in trastuzumab-treated HER2-positive metastatic breast cancer, whereas PTPN2 gain is a potential negative prognostic factor. Further studies are warranted on the role of PTPN2 in HER2 signalling.

Molecular association of functioning stroma with carcinoma cells in the ovary: A preliminary study

The cancer stroma serves an important role in tumour behaviours, including invasion, metastasis, and response to chemotherapy. The stroma of ovarian carcinoma is sometimes specialized, with luteinisation and/or hyperthecosis, and is designated as the 'functioning stroma' because it exerts endocrine function and produces sex steroid hormones. In the present study, 14 ovarian cancers with functioning stroma, comprising 7 endometrioid carcinomas and 7 clear cell carcinomas, were analysed to evaluate the molecular association of the functioning stroma with carcinoma cells. The median age of the patients was 67 years (range, 52-85 years); 13 patients were postmenopausal, and one was in perimenopause. Serum oestrogen values ranged from 10 to 129 ng/ml, with a median of 51 ng/ml. Sequence abnormalities in AT-rich interaction domain 1A (ARID1A), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA), Kirsten rat sarcoma viral proto-oncogene (KRAS) and phosphatase and tensin homolog (PTEN) were examined in whole tumours. For cancers positive for sequence abnormalities, their localization in carcinoma cells and/or stromal cells was examined. A total of 8 mutations - ARID1A (L2155L), PIK3CA (H1047R), KRAS (Q12V, E31K, Q61L), and PTEN (C105fs*8) - were identified in the whole tumours of 5 patients. Seven of these eight mutations were detected only in carcinoma cells. However, one case of endometrioid carcinoma had a KRAS (E31K) mutation in both carcinoma and stromal cells. In conclusion, although functioning stromal cells of ovarian cancer are usually thought to be non-neoplastic, some may share an origin with carcinoma cells.

MicroRNA-20b promotes proliferation of H22 hepatocellular carcinoma cells by targeting PTEN

MicroRNAs (miRNAs/miRs) are small, noncoding RNA molecules that are closely associated with the occurrence and development of tumors. miR-20b is overexpressed in hepatocellular carcinoma cell lines and tissues. However, it is not clear whether miR-20b can promote the proliferation of hepatocellular carcinoma cells. In the present study, the proliferation of H22 mouse hepatocellular carcinoma cells was detected using the Cell Counting Kit-8 assay. MiRanda software was used to predict the binding sites of miR-20b to the 3'-untranslated region (3'-UTR) of phosphatase and tensin homolog (PTEN). The 3'-UTR sequence of the PTEN gene was amplified using the polymerase chain reaction in H22 cells. The recombinant plasmid or empty plasmid was co-transfected with miR-20b mimics or miR-20b scramble into HeLa cells, and luciferase activity was assessed by Dual-Luciferase^® Reporter Assay System 24 h post-transfection. In the present study, miR-20b knockdown significantly inhibited the proliferation of H22 mouse hepatocellular carcinoma cells. In addition, miR-20b inhibition upregulated the expression of PTEN, and it was revealed that miR-20b may directly target the 3'-untranslated region of the PTEN gene. Downregulation of PTEN partially reversed the anti-proliferative effect of miR-20b on H22 cells. In conclusion, miR-20b may promote H22 cell proliferation by targeting PTEN, providing a rationale for further study investigating novel therapeutic strategies for liver cancer.

Elevated Expression of miR-19b Enhances CD8+ T Cell Function by Targeting PTEN in HIV Infected Long Term Non-progressors With Sustained Viral Suppression

Human immunodeficiency virus (HIV)-infected long-term non-progressors (LTNPs) are of particular importance because of their unique disease progression characteristics. Defined by the maintenance of normal CD4⁺T cells after more than 8 years of infection, these LTNPs are heterogeneous. Some LTNPs exhibit ongoing viral production, while others do not and are able to control viral production. The underlying basis for this heterogeneity has not been clearly elucidated. In this study, the miRNA expression profiles of LTNPs were assessed. The levels of microRNA-19b (miR-19b) were found to be significantly increased in peripheral blood mononuclear cells of LTNPs with lower rather than higher viral load. We made clear that miR-19b may regulate CD8⁺T cell functions in HIV infection, which has not been addressed before. Overexpression of miR-19b promoted CD8⁺T cell proliferation, as well as interferon-γ and granzyme B expression, while inhibiting CD8⁺T cells apoptosis induced by anti-CD3/CD28 stimulation. The target of miR-19b was found to be the "phosphatase and tensin homolog", which regulates CD8⁺T cells function during HIV infections. Furthermore, we found that miR-19b can directly inhibit viral production in in-vitro HIV infected T cells. These results highlight the importance of miR-19b to control viral levels, which facilitate an understanding of human immunodeficiency virus pathogenesis and provide potential targets for improved immune intervention.

Conditional Inactivation of Nf1 and Pten in Schwann Cells Results in Abnormal Neuromuscular Junction Maturation

The neuromuscular junction (NMJ) consists of three components, namely presynaptic motor neurons, postsynaptic muscle fibers and perisynaptic Schwann cells (PSCs). The role of Schwann cells (SCs) in regulating NMJ structural and functional development remains unclear. In this study, mice with conditional inactivation of neurofibromin 1 (Nf1) and phosphatase and tensin homolog (Pten), specifically in SCs, resulted in delayed NMJ maturation that led to delayed muscle growth, recapitulating the muscular dystrophy condition observed in human neurofibromatosis type I syndrome (NF1) patients. Expression levels of NMJ development related molecules such as cholinergic receptor, nicotinic, alpha polypeptide 1 (Chrna1), agrin (Agrn), dystrophin, muscular dystrophy (Dmd), laminin, beta 2 (Lamb2) and dystroglycan 1 (Dag1) were also downregulated. To further explore the molecular alterations in these SCs, NF1- and PTEN-related pathways were analyzed in mutant sciatic nerves. As expected, hyperactive RAS/PI3K/AKT/mTOR signaling pathways were identified, suggesting the importance of these pathways for NMJ development, and subsequent muscle maturation.

Loss of PTEN expression as diagnostic marker of endometrial precancer: A systematic review and meta-analysis

INTRODUCTION

Endometrial hyperplasia may be either a benign proliferation or a premalignant lesion. In order to differentiate these two conditions, two possible histologic classifications can be used: the World Health Organization (WHO) classification and the endometrial intraepithelial neoplasia (EIN) classification. The 2017 European Society of Gynaecological Oncology guidelines recommend the use of immunohistochemistry for tumor suppressor protein phosphatase and tensin homolog (PTEN) to improve the differential diagnosis. Nonetheless, its diagnostic accuracy has never been defined. We aimed to assess the diagnostic accuracy of immunohistochemistry for PTEN in the differential diagnosis between benign and premalignant endometrial hyperplasia.

MATERIAL AND METHODS

Electronic databases were searched from their inception to May 2018 for studies assessing immunohistochemical expression of PTEN in endometrial hyperplasia specimens. PTEN status ("loss" or "presence") was the index test; histological diagnosis ("precancer" or "benign") was the reference standard. Sensitivity, specificity, positive and negative likelihood ratios (LR+, LR-), diagnostic odds ratio (DOR), and area under the curve (AUC) on summary receiver operating characteristic curves were calculated (95% CI), with a subgroup analysis based on the histologic classification adopted (WHO vs EIN).

RESULTS

Twenty-seven observational studies with 1736 cases of endometrial hyperplasia were included. Pooled estimates showed low diagnostic accuracy: sensitivity 54% (95% CI 50%-59%), specificity 66% (63%-69%), LR+ 1.55 (1.29-1.87), LR- 0.72 (0.62-0.83), DOR 3.56 (2.02-6.28), AUC 0.657. When the WHO subgroup was compared with the EIN subgroup, higher accuracy (AUC 0.694 vs. 0.621), and higher heterogeneity in all analyses, were observed.

CONCLUSIONS

Immunohistochemistry for PTEN showed low diagnostic usefulness in the differential diagnosis between benign and premalignant endometrial hyperplasia. In the absence of further evidence, the recommendation about its use should be reconsidered.

Diabetic neuropathy research: from mouse models to targets for treatment

Diabetic neuropathy is one of the most serious complications of diabetes, and its increase shows no sign of stopping. Furthermore, current clinical treatments do not yet approach the best effectiveness. Thus, the development of better strategies for treating diabetic neuropathy is an urgent matter. In this review, we first discuss the advantages and disadvantages of some major mouse models of diabetic neuropathy and then address the targets for mechanism-based treatment that have been studied. We also introduce our studies on each part. Using stem cells as a source of neurotrophic factors to target extrinsic factors of diabetic neuropathy, we found that they present a promising treatment.

Hypoxia-induced ARHGAP26 deficiency inhibits the proliferation and migration of human ductus arteriosus smooth muscle cell through activating RhoA-ROCK-PTEN pathway

The Rho family plays crucial roles in O₂ -induced vasoconstriction, cell proliferation, and migration. Rho GTPase-activating protein 26 (ARHGAP26) is a GTPase-activating protein for the small GTPases of the Rho family. Our previous studies have demonstrated that ARHGAP26 expression was significantly downregulated in patent human ductus arteriosus (DA) tissue. However, its role underlying the maintenance of DA patency is unclear. In this study, patent (fetal) and constricted (newborn) mouse DA tissues were harvested to confirm the differences in the levels of expression of ARHGAP26. Human DA smooth muscle cells (DASMCs) were isolated and cultured in vitro and used to test the function of ARHGAP26. The expression of ARHGAP26 was significantly lower in patent (fetal) than constricted (newborn) mouse DA. ARHGAP26-knocked-down human DASMCs showed reduced proliferation and migration, which are both crucial to anatomic closure of DA. Moreover, after culturing under hypoxic conditions, the expression of ARHGAP26 in human DASMCs was significantly lower and hypoxia-induced ARHGAP26 deficiency activated the phosphorylation level of phosphatase and tensin homolog (PTEN) in DASMCs by mediating the activity of RhoA and RhoA-associated kinase 1 (ROCK1). Use of Y27632, an inhibitor of ROCK which further reduces the phospholipid activity of PTEN can reverse the inhibitory effect of PTEN on the proliferation and migration of human DASMCs. This provides insight into the molecular regulation of the RhoA-ROCK-PTEN pathway in DA smooth muscle cells, which may be a suitable therapeutic target or diagnostic biomarker for perinatal DA tone management.

MicroRNA-494-3p protects rat cardiomyocytes against septic shock via PTEN

The aim of the present study was to investigate the role of microRNA (miR)-494-3p in myocardial injury in patients with septic shock and the underlying mechanism. A total of 22 patients with sepsis and 17 patients with septic shock were included in the present study. In addition, 20 healthy subjects were recruited as the control group. Peripheral blood was collected from all subjects and a rat cardiomyocyte model of myocardial injury was constructed. Reverse transcription-quantitative polymerase chain reaction was used to measure miR-494-3p expression, while cell counting kit-8 assays were performed to assess cell proliferation. Flow cytometry was performed to investigate cell cycle distribution and apoptosis. Lactate dehydrogenase (LDH) assays were performed to measure LDH levels. ELISA was also performed to measure LDH, tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels in cell culture supernatants. Western blotting was employed to detect phosphatase and tensin homolog (PTEN) protein expression and dual luciferase reporter assays were performed to identify the interaction between miR-494-3p and PTEN mRNA. Reduced miR-494-3p expression was correlated with myocardial damage in patients with septic shock. Sera from patients with septic shock downregulated miR-494-3p expression in rat cardiomyocytes. miR-494-3p overexpression inhibited rat cardiomyocyte injury induced by treatment with sera from patients with septic shock. Furthermore, miR-494-3p overexpression reduced the synthesis and release of TNF-α and IL-6 from rat cardiomyocytes. PTEN knockdown alleviated rat cardiomyocyte injury following treatment with serum from patients with septic shock. PTEN was demonstrated to induce the release of TNF-α and IL-6 from rat cardiomyocytes treated with septic shock serum, while miR-494-3p was demonstrated to bind to the 3′-untranslated seed region of PTEN mRNA to regulate its expression. The results of the present study suggest that miR-494-3p is downregulated in the peripheral blood of patients with septic shock and is negatively correlated with myocardial injury. The present study also indicates that miR-494-3p regulates PTEN expression, inhibits sepsis-induced myocardial injury and protects the function of cardiomyocytes. The protective effect and mechanism of action of miR-494-3p indicate that it has potential for use in the clinical diagnosis and therapy of myocardial damage.

PTEN in propofol-induced insulin resistance in mouse primary hepatocytes

Propofol is the most common intravenous anesthetic agent used in clinical practice. Propofol can induce insulin resistance in mouse primary hepatocytes, however the molecular mechanism through which propofol acts remains largely unknown. Based on previous studies, it was hypothesized that phosphatase and tensin homolog (PTEN) is involved in propofol-mediated insulin resistance. The aim of the present study was to investigate the biological function of PTEN and its molecular mechanism in propofol-induced insulin resistance in mouse primary hepatocytes. Mouse primary hepatocytes were treated with propofol and transfected with small interfering RNA (siRNA)-996 to silence the endogenous expression of PTEN. The current study assessed the effects of propofol and PTEN knockdown on the expression of PTEN and several key enzymes of the phosphoinositide 3-kinase/protein kinase B/glycogen synthase kinase-3β signaling pathway, as well as the glycogen content in mouse primary hepatocytes. Treatment with propofol significantly increased protein and mRNA PTEN expression in mouse primary hepatocytes. In addition, knockdown of PTEN reversed propofol-induced insulin resistance in mouse primary hepatocytes. The present study indicated that PTEN serves a role in the physiological process of propofol-induced insulin resistance in mouse primary hepatocytes, and PTEN inhibition may be a potential target for therapeutic intervention against propofol-induced adverse effects.

MicroRNA-146b induces the PI3K/Akt/NF-κB signaling pathway to reduce vascular inflammation and apoptosis in myocardial infarction by targeting PTEN

The aim of the present study was to investigate the function of microRNA-146b on myocardial infarction and the mechanism. An MTT assay, Annexin V/propidium iodide (PI) apoptosis assay, ELISA kits, western blot analysis and a caspase-3/8 activity assay were used to measure cell growth, vascular apoptosis inflammatory factors, and the B-cell lymphoma 2-associated X protein (Bax), phosphatase and tensin homolog (PTEN), phosphoinositide 3-kinase (PI3K)/Akt/nuclear factor (NF)-κB signaling pathway. The expression of microRNA-146b was downregulated in the myocardial infarction rat model, compared with the control group. In an in vitro model of myocardial infarction, the downregulation of microRNA-146b increased inflammatory factors, vascular apoptosis, caspase-3/8 activity and the protein expression of Bax. MicroRNA-146b reduced vascular apoptosis, caspase-3/8 activity and the protein expression of Bax. MicroRNA-146b also regulated the PI3K/Akt/NF-κB signaling pathway to mediate vascular inflammation and apoptosis in myocardial infarction by PTEN. A PI3K inhibitor decreased the effect of microRNA-146b on vascular inflammation and apoptosis following myocardial infarction. In conclusion, microRNA-146b mediated vascular inflammation and apoptosis in patients with myocardial infarction, which may be associated with activation of the PI3K/Akt/NF-κB signaling pathway by PTEN.

LncRNA ANCR promotes proliferation and radiation resistance of nasopharyngeal carcinoma by inhibiting PTEN expression

Introduction

Antidifferentiation noncoding RNA (ANCR) is a newly identified long noncoding RNA, which is reported to function as an oncogene in multiple human cancers. However, its function in nasopharyngeal carcinoma (NPC) and underlying mechanism are still unclear.

Materials and methods

We explored the expression of ANCR in NPC tissues and cells by real-time PCR and analyzed the relationship between ANCR expression and clinicopathological characteristics of NPC patients by Pearson's chi-squared test. Then we inhibited ANCR expression in NPC cells using siRNAs and evaluated the effect of ANCR expression on cell proliferation, colony formation, and radiosensitivity by cell counting kit-8 assay and colony formation assay. We used RT-PCR and Western blot analyses to search target genes of ANCR. Also, we used RNA immunoprecipitation (RIP) assay and chromatin immunoprecipitation assay to study the molecular mechanism in this regulation.

Results

We found that ANCR was upregulated in NPC tissues and cells. ANCR expression was significantly correlated with tumor size and TNM stage. Further, ANCR knockdown inhibited NPC cell growth and radiation resistance. Mechanistically, we found that PTEN was upregulated in ANCR knockdown NPC cells. In addition, RIP assay indicated that EZH2, the oncogenic histone methyltransferase of polycomb repressive complex 2, interacted with ANCR in NPC cells. More importantly, the binding of EZH2 and deposition of relevant negative histone marker H3K27me3 on PTEN promoter depended on ANCR expression.

Conclusion

ANCR expression is upregulated in NPC and promotes NPC growth and radiation resistance through an epigenetic regulation of PTEN expression.

miR-106a contributes to prostate carcinoma progression through PTEN

Prostate carcinoma is a global health problem and is estimated to be diagnosed in 1.1 million men/year, making this malignancy the second most frequently diagnosed cancer in males worldwide. micro RNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression at the post-transcriptional level. miRNAs contribute to cancer development and progression, and are expressed differently in normal tissues and cancers. In the present study, the biological function of miR-106a in the human prostate carcinoma and the associated regulatory mechanisms were investigated. miR-106a was significantly upregulated in human prostate cancer tissues when compared with normal tissues (P<0.05), and the overexpression of miR-106a was identified to promote PC-3 cell growth. Additionally, miRNA-106a inhibition significantly suppressed PC-3 cell growth. Furthermore, it was observed that the phosphatase and tensin homolog (PTEN) expression level was negatively associated with miR-106a expression level, and miRNA-106a directly targeted PTEN in the PC-3 cells. PTEN overexpression has a similar effect on PC-3 cell growth as loss of miR-106a. Taken together, the results of the present study indicate that upregulated miR-106a regulates PC-3 cell proliferation through PTEN. These results suggest that appropriate manipulation of miR-106a may provide a novel strategy in the future treatment of human prostate cancer.

MicroRNA‑214 suppresses propofol‑induced neuroapoptosis through activation of phosphoinositide 3‑kinase/protein kinase B signaling by targeting phosphatase and tensin homolog expression

The present study aimed to investigate the effects of microRNA (miR)‑214 on neuroapoptosis induced by propofol and the possible mechanism of its anti‑apoptotic effects. Initially, it was observed that miR‑214 expression was upregulated in propofol‑induced neuroapoptosis rats. Next, propofol‑treated nerve cells were transfected with miR‑214 mimics. The results revealed that miR‑214 overexpression induced apoptosis, inhibited cell proliferation, inhibited cyclin D1 protein expression, promoted caspase‑3 activity and B‑cell lymphoma 2‑associated X protein expression, and enhanced the levels of inflammation factors in nerve cells treated with propofol. In addition, miR‑214 overexpression suppressed phosphoinositide 3‑kinase/protein kinase B (PI3K/Akt) signaling by targeting the activation of phosphatase and tensin homolog (PTEN) and nuclear factor‑κB expression in nerve cells treated with propofol. Treatment with a PTEN inhibitor successfully suppressed the PTEN protein expression and decreased the apoptosis of propofol‑treated nerve cells subsequent to miR‑214 overexpression through PI3K/Akt signaling. In conclusion, the present study data revealed that miR‑214 suppressed propofol‑induced neuroapoptosis through the activation of PI3K/Akt signaling by targeting PTEN expression.

PTEN inhibitor VO-OHpic attenuates inflammatory M1 macrophages and cardiac remodeling in doxorubicin-induced cardiomyopathy

Doxorubicin (Doxo) is an effective agent commonly used in cancer therapeutics. Unfortunately, Doxo treatment can stimulate cardiomyopathy and subsequent heart failure, limiting the use of this drug. The role of phosphatase and tensin homolog (PTEN) in apoptosis has been documented in Doxo-induced cardiomyopathy (DIC) and heart failure models. However, whether direct inhibition of PTEN attenuates apoptosis, cardiac remodeling, and inflammatory M1 macrophages in the DIC model remains elusive. Therefore, the present study was designed to understand the effects of VO-OHpic (VO), a potent inhibitor of PTEN, in reducing apoptosis and cardiac remodeling. At day 56, echocardiography was performed, which showed that VO treatment significantly ( P < 0.05) improved heart function. Immunohistochemistry, TUNEL, and histological staining were used to determine apoptosis, proinflammatory M1 macrophages, anti-inflammatory M2 macrophages, and cardiac remodeling. Our data show a significant increase in apoptosis, hypertrophy, fibrosis, and proinflammatory M1 macrophages with Doxo treatment, whereas VO treatment significantly reduced apoptosis, adverse cardiac remodeling, and proinflammatory M1 macrophages significantly ( P < 0.05) compared with the Doxo-treated group. Western blot analysis confirmed the reduction of phosphorylated PTEN and increase in phosphorylated AKT protein expression in the Doxo + VO-treated group. Moreover, VO administration increased anti-inflammatory M2 macrophages. Collectively, our data suggest that VO treatment attenuates apoptosis and adverse cardiac remodeling, a process that is mediated through the PTEN/AKT pathway, resulting in improved heart function in DIC. NEW & NOTEWORTHY Doxorubicin-induced cardiomyopathy (DIC) is still a major issue in patients with cancer. These novel findings on the phosphatase and tensin homolog inhibitor VO-OHpic in DIC is the first report, as per the best of our knowledge, that VO-OHpic significantly decreases apoptosis, fibrosis, hypertrophy, adverse cardiac remodeling, and proinflammatory M1 macrophages and increases anti-inflammatory M2 macrophages along with significantly improved cardiac function. VO-OHpic could be a future therapeutic agent for patients with DIC.

BMI1 promotes cardiac fibrosis in ischemia-induced heart failure via the PTEN-PI3K/Akt-mTOR signaling pathway

Cardiac fibrosis has been known to play an important role in the etiology of heart failure after myocardial infarction (MI). B lymphoma Mo-MLV insertion region 1 homolog (BMI1), a transcriptional repressor, is important for fibrogenesis in the kidneys. However, the effect of BMI1 on ischemia-induced cardiac fibrosis remains unclear. BMI1 was strongly expressed in the infarct region 1 wk post-MI in mice and was detected by Western blot and histological analyses. Lentivirus-mediated overexpression of BMI1 significantly promoted cardiac fibrosis, worsened cardiac function 4 wk after the intervention in vivo, and enhanced the proliferation and migration capabilities of fibroblasts in vitro , whereas downregulation of BMI1 decreased cardiac fibrosis and prevented cardiac dysfunction in mice 4 wk post-MI in vivo. Furthermore, upregulated BMI1 inhibited phosphatase and tensin homolog (PTEN) expression, enhanced phosphatidylinositol 3-kinase (PI3K) expression, and increased the phosphorylation level of Akt and mammalian target of rapamycin (mTOR) in mice 4 wk after lentiviral infection, which was in accordance with the changes seen in their infarcted myocardial tissues. At the same time, the effects of BMI1 on cardiac fibroblasts were reversed in vitro when these cells were exposed to NVP-BEZ235, a dual-kinase (PI3K/mTOR) inhibitor. In conclusion, BMI1 is associated with cardiac fibrosis and dysfunction after MI by regulating cardiac fibroblast proliferation and migration, and these effects could be partially explained by the regulation of the PTEN-PI3K/Akt-mTOR pathway. NEW & NOTEWORTHY Ischemia-induced B lymphoma Mo-MLV insertion region 1 homolog (BMI1) significantly promoted cardiac fibrosis and worsened cardiac function in vivo, whereas downregulation of BMI1 decreased cardiac fibrosis and prevented cardiac dysfunction in myocardial infarcted mice. BMI1 also enhanced proliferation and migration capabilities of fibroblasts in vitro; these effects were reversed by NVP-BEZ235. Effects of BMI1 on cardiac fibrosis could be partially explained by regulation of the phosphatase and tensin homolog-phosphatidylinositol 3-kinase/Akt-mammalian target of rapamycin pathway.

Increased serum levels of miR-214 in patients with PCa with bone metastasis may serve as a potential biomarker by targeting PTEN

MicroRNAs (miRNAs/miRs) are identified to serve key functions in the progression of various tumors. miR-214 is aberrantly expressed in various types of cancer. In the present study, the function of miR-214 and its feasibility as a potential non-invasive biomarker for patients with prostate cancer (PCa) in a hyperplasia group and a control group were investigated. First, RNA was isolated from the serum of 75 patients with PCa with bone metastasis, 65 patients with PCa with no bone metastasis and 70 healthy controls. The level of miR-214 expression was significantly upregulated in the serum of the bone metastasis group compared with the healthy control and non-bone metastasis groups. Expression levels of alkaline phosphatase (ALP), bone sialoprotein (BSP), collagen type I pyridine crosslinking peptide (ICTP) were also evaluated. The results indicated that serum levels of BSP, ALP and ICTP were increased in the bone metastasis group compared with that in the non-bone metastasis group, hyperplasia group and the control group (P<0.05). The expression level of miR-214 is positively associated with poorly differentiated tumors in patients with PCa with a Gleason score >7 (P<0.05). Western blot analysis demonstrated that phosphatase and tensin homolog (PTEN) was a target gene of miR-214. Additionally, silencing of PTEN significantly increased the invasive ability of PC3 cells even when miR-214 expression was inhibited. In summary, serum miR-214 expression may serve as a potential novel non-invasive biomarker for PCa screening through targeting PTEN.

Interleukin-1β/nuclear factor-κB signaling promotes osteosarcoma cell growth through the microRNA-181b/phosphatase and tensin homolog axis

So far, microRNA has attracted plenty of interest due to its role in tumorigenesis. Reportedly, miR-181b may be involved in the tumorigenesis of osteosarcoma (OS). In the current study, we attempted to investigate the detailed function and mechanism of miR-181b in OS carcinogenesis. Herein, miR-181a, miR-181b, miR-181c, and miR-181d expressions in OS tissues were higher than that in nontumor tissue samples as examined real-time polymerase chain reaction. Via direct targeting, miR-181b negatively regulated the expression of phosphatase and tensin homolog (PTEN), a well-known tumor suppressor. Furthermore, a small interfering RNA strategy was used to find that interleukin (IL)-1B and nuclear factor-κB (NF-κB) regulate miR-181b and PTEN expression. Consequently, the repression of PTEN by miR-181b promotes OS cell proliferation. In summary, our data support a critical role for NF-κB-dependent upregulation of miR-181b, which further inhibited PTEN expression and promoted the cell proliferation of OS cell lines. The above findings represent a new pathway for the repression of PTEN and the promotion of cell proliferation upon IL-1β induction.

MicroRNA-423 promotes proliferation, migration and invasion and induces chemoresistance of endometrial cancer cells

Altered microRNA expression serves essential roles in tumorigenesis and progression in endometrial cancer. In the present study the effect of miR-423 on proliferation, chemosensitivity, migration and invasion of endometrial cancer cells was examined. A WST-1 assay was used to examine the proliferation of HEC-1B and Ishikawa endometrial cancer cells with either upregulation or downregulation of miR-423, with or without cisplatin treatment. The migration and invasion of HEC-1B and Ishikawa endometrial cancer cells were examined via Transwell migration and Matrigel invasion assays. Protein expression levels, including B cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein, E- and N-cadherin, snail, vimentin, phosphatase and tensin homolog (PTEN) and protein kinase B (AKT) were examined by western blotting. A caspase-Glo3/7 assay was carried out to evaluate the effect of miR-423 on cisplatin-induced apoptosis in HEC-1B and Ishikawa endometrial cancer cells. Overexpression of miR-423 enhanced the proliferation, and increased migration and invasion in endometrial cancer cells. miR-423 also decreased the sensitivity of endometrial cancer cells following cisplatin treatment. miR-423 inhibited cisplatin-induced apoptosis in endometrial cancer cells by regulation of caspase 3/7 and Bcl-2 expression. Furthermore, the E-cadherin expression was significantly decreased, and the expression of N-cadherin, snail and Vimentin were increased in both HEC-1B cells and Ishikawa cells following overexpression of miR-423. Conversely, downregulation of miR-423 increased the expression of E-cadherin and decreased the expression of N-cadherin, snail and Vimentin. Further experiments demonstrated that the expression levels of PTEN and phosphorylated-AKT in HEC-1B and Ishikawa endometrial cancer cells was decreased and increased, respectively, following aberrant expression of miR-423. miR-423 displayed an important role in tumorigenesis and progression in endometrial cancer cells, and may therefore be used as a potential biomarker to predict chemotherapy response and prognosis in endometrial cancer.

miRNA-21 inhibition inhibits osteosarcoma cell proliferation by targeting PTEN and regulating the TGF-β1 signaling pathway

The present study aimed to investigate the role of microRNA (miRNA)-21 in the growth of osteosarcoma. A total of 46 patients with osteosarcoma and 20 healthy controls were included in the study. The expression of miRNA-21 was detected by reverse transcription-quantitative polymerase chain reaction in tumor tissues and adjacent healthy tissues from patients with osteosarcoma, as well as the serum of patients with osteosarcoma and the healthy controls was. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic values of serum miRNA-21 for osteosarcoma at different T stages. Survival curves plotted using the Kaplan-Meier method were used to evaluate the prognostic value. miRNA-21 knockdown osteosarcoma cell lines were established and their effects on cell proliferation were explored using a Cell Counting Kit-8 assay. The effect of miRNA-21 knockdown on the protein expression of phosphatase and tensin homolog (PTEN) and transforming growth factor (TGF)-β1 was detected by western blot analysis. The expression levels of miRNA-21 in tumor tissues were significantly higher compared with the adjacent healthy tissues in the majority of patients with osteosarcoma. The serum miRNA-21 increased as the T-stage of osteosarcoma increased. Serum miRNA-21 may be used to effectively diagnose osteosarcoma and predict the prognosis of the disease. miRNA-21 knockdown inhibited the proliferation of osteosarcoma and promoted the expression of PTEN and TGF-β1 proteins in the osteosarcoma cells. However, TGF-β1 inhibitor treatment reduced the inhibitory effects of miRNA-21 knockdown on osteosarcoma cell proliferation. In conclusion, miRNA-21 inhibition may inhibit osteosarcoma cell proliferation by targeting PTEN and regulating the TGF-β1 signaling pathway.

Stanozolol administration combined with exercise leads to decreased telomerase activity possibly associated with liver aging

Anabolic agents are doping substances which are commonly used in sports. Stanozolol, a 17α‑alkylated derivative of testosterone, has a widespread use among athletes and bodybuilders. Several medical and behavioral adverse effects are associated with anabolic androgenic steroids (AAS) abuse, while the liver remains the most well recognized target organ. In the present study, the hepatic effects of stanozolol administration in rats at high doses resembling those used for doping purposes were investigated, in the presence or absence of exercise. Stanozolol and its metabolites, 16‑β‑hydroxystanozolol and 3'‑hydroxystanozolol, were detected in rat livers using liquid chromatography‑mass spectrometry (LC‑MS). Telomerase activity, which is involved in cellular aging and tumorigenesis, was detected by examining telomerase reverse transcriptase (TERT) and phosphatase and tensin homolog (PTEN) expression levels in the livers of stanozolol‑treated rats. Stanozolol induced telomerase activity at the molecular level in the liver tissue of rats and exercise reversed this induction, reflecting possible premature liver tissue aging. PTEN gene expression in the rat livers was practically unaffected either by exercise or by stanozolol administration.

Jumonji AT-rich interactive domain 1B promotes the growth of pancreatic tumors via the phosphatase and tensin homolog/protein kinase B signaling pathway

Jumonji AT-rich interactive domain 1B (JARID1B) has been revealed to remove methyl residues from methylated lysine 4 on histone H3 (H3K4) and has also been reported to be associated with the progression of numerous types of tumor. However, its roles and mechanisms in pancreatic cancer (PC) remain unknown. The present study demonstrated that JARID1B is elevated in PC and is associated with the growth of pancreatic tumors. Overexpression of JARID1B significantly promoted the proliferation in vitro and tumor formation in vivo of PC cells. Furthermore, silencing the expression of JARID1B in other PC cells revealed opposite effects. Further research revealed that JARID1B exerted its function through modulation of H3K4me3 at the phosphatase and tensin homolog (PTEN) gene promoter which was associated with inactive PTEN transcription. To the best of our knowledge, the present study was the first to demonstrate that JARID1B promotes the growth of PC and that targeting JARID1B may be a useful strategy to suppress the progression of PC.

Genetic analysis and phosphoinositide 3-kinase/protein kinase B signaling pathway status in ovarian endometrioid borderline tumor samples

Ovarian endometrioid borderline tumors (EBTs) are extremely rare, and are thought to be precursors of endometrioid carcinoma, beginning as adenofibroma or endometriosis and progressing in a slow, stepwise manner. In endometrioid carcinomas, a high frequency of activating mutations in phosphatase and tensin homolog (PTEN), β-catenin or AT-rich interaction domain 1A (ARID1A) genes, and the activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway have been observed. However, the frequency of these alterations in EBTs and how they contribute to tumor progression remain unclear. To the best of our knowledge, this is the first study to assess the status of the PI3K/AKT signaling pathway in EBTs, in association with PTEN and ARID1A mutations. PTEN mutations were observed in EBTs and also in the area of endometriosis without atypia. However, the PI3K/AKT signaling pathway was revealed to be activated only in EBTs. The observations of the present study suggest that the PTEN mutation represents an early event in EBT tumorigenesis, while additional genetic alterations may be necessary to activate the PI3K/AKT signaling pathway and induce the development of the invasive carcinoma.

Matrine inhibits TPC-1 human thyroid cancer cells via the miR-21/PTEN/Akt pathway

Papillary thyroid cancer (PTC) is the primary type of thyroid cancer and the most widespread endocrine malignancy. Matrine is a traditional Chinese medicine and has been demonstrated as a promising alternative drug for the treatment of TPC-1 human PTC. In the present study, the therapeutic effects and the underlying molecular mechanisms of matrine on TPC-1 cells were investigated. Treatment with matrine at the concentrations of 1, 2, 5, 10 and 20 mg/ml inhibited TPC-1 cell proliferation by up to 95.8% (for 20 mg/ml matrine). Flow cytometry indicated that treatment with 10 mg/ml matrine induced up to 61.8% apoptosis of the TPC-1 cells and the cell cycle was arrested at the G0/G1 phase following treatment with matrine (2, 5 and 10 mg/ml) for 48 h. Quantitative polymerase chain reaction indicated that the expression of microRNA (miR)-21 was downregulated and phosphatase and tensin homolog (PTEN) mRNA levels increased up to 1.66-fold following treatment with matrine, and RAC-α serine/threonine-protein kinase (Akt) mRNA levels were downregulated 0.34-fold following treatment with 5 mg/ml matrine, compared with the normal control group. Western blot analysis indicated that matrine at 2 and 5 mg/ml increased levels of the miR-21 target PTEN and decreased the levels of phosphorylated (p)Akt. Furthermore, miR-21 mimic transfection decreased the expression levels of PTEN and increased the levels of pAkt. These results suggested that the miR-21/PTEN/Akt pathway may be one of the mechanisms by which matrine induces apoptosis and cell cycle arrest in TPC-1 thyroid cancer cells. Matrine is an alternative potential drug for the treatment of thyroid cancer.