Novel long non-coding RNA lncAMPC downregulates PTEN via miR-214 to promote nasopharyngeal carcinoma progression.

Long non-coding RNAs (lncRNAs) are a type of non-coding RNAs with transcript lengths exceeding 200 nt. lncRNAs suppress or promote cancer mainly by regulating gene expression. The aim of this study was to explore the role of lncRNAs activated in metastatic PCa (lncAMPC) in nasopharyngeal carcinoma (NPC). Total RNAs were isolated from NPC and adjacent non-tumor tissues from 60 NPC patients and subjected to RT-qPCR to analyze differential expression of lncAMPC and miR-214. The roles of lncAMPC and miR-214 in regulating PTEN expression were analyzed using RT-qPCR and Western blot. Cell proliferation was analyzed using the BrdU assay. The results showed that lncAMPC was overexpressed in NPC tissues and was localized in both nuclei and cytoplasms of NPC cells. MiR-214 was positively correlated with lncAMPC. LncAMPC overexpression upregulated miR-214 and indirectly downregulated PTEN via miR-214. BrdU incorporation assay showed that lncAMPC and miR-214 overexpression increased cell proliferation. PTEN overexpression completely reversed the promoting effects of lncAMPC and miR-214 overexpression on cell proliferation. Therefore, lncAMPC might downregulate PTEN via miR-214 to increase NPC cell proliferation.

Collision tumors revealed by prospectively assessing subtype-defining molecular alterations in 904 individual prostate cancer foci.

BACKGROUNDProstate cancer is multifocal with distinct molecular subtypes. The utility of genomic subtyping has been challenged due to inter- and intrafocal heterogeneity. We sought to characterize the subtype-defining molecular alterations of primary prostate cancer across all tumor foci within radical prostatectomy (RP) specimens and determine the prevalence of collision tumors.METHODSFrom the Early Detection Research Network cohort, we identified 333 prospectively collected RPs from 2010 to 2014 and assessed ETS-related gene (ERG), serine peptidase inhibitor Kazal type 1 (SPINK1), phosphatase and tensin homolog (PTEN), and speckle type BTB/POZ protein (SPOP) molecular status. We utilized dual ERG/SPINK1 immunohistochemistry and fluorescence in situ hybridization to confirm ERG rearrangements and characterize PTEN deletion, as well as high-resolution melting curve analysis and Sanger sequencing to determine SPOP mutation status.RESULTSBased on index focus alone, ERG, SPINK1, PTEN, and SPOP alterations were identified in 47.5%, 10.8%, 14.3%, and 5.1% of RP specimens, respectively. In 233 multifocal RPs with ERG/SPINK1 status in all foci, 139 (59.7%) had discordant molecular alterations between foci. Collision tumors, as defined by discrepant ERG/SPINK1 status within a single focus, were identified in 29 (9.4%) RP specimens.CONCLUSIONInterfocal molecular heterogeneity was identified in about 60% of multifocal RP specimens, and collision tumors were present in about 10%. We present this phenomenon as a model for the intrafocal heterogeneity observed in previous studies and propose that future genomic studies screen for collision tumors to better characterize molecular heterogeneity.FUNDINGEarly Detection Research Network US National Cancer Institute (NCI) 5U01 CA111275-09, Center for Translational Pathology at Weill Cornell Medicine (WCM) Department of Pathology and Laboratory Medicine, US NCI (WCM SPORE in Prostate Cancer, P50CA211024-01), R37CA215040, Damon Runyon Cancer Research Foundation, US MetLife Foundation Family Clinical Investigator Award, Norwegian Cancer Society (grant 208197), and South-Eastern Norway Regional Health Authority (grant 2019016 and 2020063).

miR-129-5p restores cardiac function in rats with chronic heart failure by targeting the E3 ubiquitin ligase Smurf1 and promoting PTEN expression.

Chronic heart failure (CHF) is a prevalent health concern with complex pathogenesis. This current study set out to estimate the function of the miR-129-5p/Smurf1/PTEN axis on cardiac function injury in CHF. The model of CHF in rats was established. The cardiac function indexes, myocardial tissue damage, and oxidative stress-related factors in CHF rats were evaluated after the interference of Smurf1/miR-129-5p/PTEN. The targeting relationships between miR-129-5p and Smurf1 and between PTEN and Smurf1 were verified. It was found that that after modeling, cardiac functions were impaired, heart/left ventricular/lung weight and the myocardial structure was destroyed, and the degree of fibrosis of myocardial tissue was increased. After Smurf1 knockdown, the cardiac function, myocardial structure, and oxidative stress were improved, and the fibrosis in myocardial tissue was decreased. Smurf1 was a target of miR-129-5p. miR-129-5p could annul the protective effect of Smurf1 silencing on CHF rats. Smurf1 inhibited PTEN expression by promoting PTEN ubiquitination, while miR-129-5p enhanced PTEN expression by inhibiting Smurf1. Meanwhile, overexpression of PTEN annulled the cardiac dysfunction in CHF rats induced by Smurf1. In conclusion, miR-129-5p targeted Smurf1 and repressed the ubiquitination of PTEN, and promoted PTEN expression, thus improving the cardiac function of CHF rats.

PTEN Loss and PD-L1 Expression of Different Histological Patterns of Prostate Cancer.

AIMS: Although several studies have evaluated PTEN loss in Prostatic Adenocarcinoma (PCa), PTEN loss correlation with different histological patterns only has a few studies. Although several studies have evaluated PD-L1 expression in PCa and its correlation with Gleason scores, as far as we know, there are no prior studies that have included a comparison between PD-L1 expression and histological patterns of PCa. This study aims to evaluate PTEN loss and PD-L1 expression by immunohistochemistry in different histological patterns of PCa. METHODS: The current study included consecutive 98 radical prostatectomy specimens with 151 foci with different Gleason Grade (GG) patterns. RESULTS: The highest frequency of PTEN loss was observed in GG4 cribriform and glomeruloid patterns (59.3%, p < 0.001). Combined score (CS) PD-L1 positivity was observed in fourteen patients (14.2%). Tumor cell (TC) and tumor-associated inflammatory cells (IC) PD-L1 positivity was observed in 10 (10.2%) and 7 (7.1%) patients. The highest frequency of PD-L1 expression was observed in the GG5 pattern, and between GG4 patterns, the irregular pattern had the highest PD-L1 positivity. CONCLUSIONS: In conclusion, in our cohort of consecutive unselected cases of prostatic carcinoma, we observed the highest PTEN loss rate in the GG4 cribriform and glomeruloid pattern and the highest PD-L1 expression rate in the GG5 and GG4 irregular patterns. These results may predict molecular differences between different histological patterns in PCa and may be used to inform a treatment decision. Future studies should investigate these differences between histological patterns of PCa to predict response to immunotherapy in larger cohorts.

Silencing lncRNA LINC01410 suppresses cell viability yet promotes apoptosis and sensitivity to temozolomide in glioblastoma cells by inactivating PTEN/AKT pathway via targeting miR-370-3p.

BACKGROUND: Long non-coding RNAs (LncRNAs) are involved in glioblastoma (GBM), but the role of long intergenic non-protein coding RNA 01410 (lncRNA LINC01410) is poorly understood. METHODS: The expression of LINC01410 in GBM tissues and cells was analyzed. After transfection or temozolomide (TMZ) treatment, the cell viability and apoptosis were detected using cell counting kit-8 assay and flow cytometry. The targeting relationship between LINC01410 and microRNA (miR)-370-3p was confirmed by dual-luciferase reporter assay. Expressions of LINC01410, miR-370-3p and drug resistance- and Phosphatase and Tensin Homolog (PTEN)/AKT pathway-related factors were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. RESULTS: LINC01410 expression was upregulated in GBM, and silencing of LINC01410 decreased cell viability. A slowed decreased trend in cell viability yet an increased half maximal inhibitory concentration (IC50 for TMZ) value and increased expressions of drug resistance-related factors as well as LINC01410 were found in TMZ-resistant GBM cells. Silencing of LINC01410 also decreased the IC50 value yet promoted the sensitivity and apoptosis in TMZ-resistant cells, while upregulating the expression of PTEN and downregulating the phosphorylation of AKT. MiR-370-3p could competitively bind to LINC01410 and its expression was decreased in both parental and TMZ-resistant GBM cells. Downregulation of miR-370-3p reversed the effects of LINC01410 silencing on cell viability, apoptosis and the expressions of miR-370-3p and PTEN/AKT pathway-related factors. CONCLUSION: Silencing of LINC01410 inhibits cell viability yet enhances apoptosis and sensitivity to TMZ in GBM cells by inactivating PTEN/AKT pathway via targeting miR-370-3p.

Modeling PTEN overexpression-induced microcephaly in human brain organoids.

The phosphatase and tensin homolog (PTEN) protein, encoded by the PTEN gene on chromosome 10, is a negative regulator of the phosphoinositide 3-kinase (PI3K) signaling pathway. Loss of PTEN has been linked to an array of human diseases, including neurodevelopmental disorders such as macrocephaly and autism. However, it remains unknown whether increased dosage of PTEN can lead to human disease. A recent human genetics study identifies chromosome 10 microduplication encompassing PTEN in patients with microcephaly. Here we generated a human brain organoid model of increased PTEN dosage. We showed that mild PTEN overexpression led to reduced neural precursor proliferation, premature neuronal differentiation, and the formation of significantly smaller brain organoids. PTEN overexpression resulted in decreased AKT activation, and treatment of wild-type organoids with an AKT inhibitor recapitulated the reduced brain organoid growth phenotypes. Together, our findings provide functional evidence that PTEN is a dosage-sensitive gene that regulates human neurodevelopment, and that increased PTEN dosage in brain organoids results in microcephaly-like phenotypes.

miR-934 promotes breast cancer metastasis by regulation of PTEN and epithelial-mesenchymal transition.

Breast cancer (BC) is the most commonly diagnosed malignancy and the leading cause of cancer-related mortality among females. Over 90 % of the cases of death in BC patients are attributed to tumor cell metastasis. Therefore, it is urgently needed to investigate the molecular mechanisms of BC metastasis. The expression of miRNA in BC was evaluated by qRT-PCR and bioinformatics analysis. Clone formation, EdU assays, and subcutaneous xenograft model were used to test the growth of BC cells. Wound healing, transwell assays, and lung-metastasis model were used to explore the effect of miR-934 knockdown on cell metastasis. The miR-934 targets in BC were identified through bioinformatics analysis and luciferase reporter assays. The expression of protein was tested by western blot. The binding of mRNA and RNA-binding-protein was verified using RIP assays. miR-934 expression was significantly elevated in BC tissues, especially in those with lymph node metastasis and associated with poor patient prognosis. Experiments in vitro and in vivo showed that that upregulated miR-934 was not necessarily required for the growth of BC cells. However, miR-934 knockdown significantly inhibited the migration and invasion abilities of BC cells. Moreover, PTEN as identified as the direct target of miR-934 in BC, and miR-934 could promote BC cell metastasis by regulation of PTEN and epithelial-mesenchymal transition (EMT). Our results suggested that targeting miR-934 may be a practical treatment for BC cell metastasis.

Circ_0019435 Exerts Its Functions in the Cellular Process of Cervical Cancer via Epigenetically Silencing DKK1 and PTEN.

Cervical cancer (CC) is the most serious gynecological malignancy among women worldwide. As a subtype of noncoding RNAs (ncRNAs), circular RNAs (circRNAs) play important roles in the regulation of gene expression and cancer progression. It was discovered from the cancer-specific circRNA database (CSCD) that circ_0019435 was mainly distributed in the nucleus of HeLa-S3 cells. However, few researches have mentioned circ_0019435 with its function in cancers. The present study uncovered that circ_0019435 was upregulated in CC cells by qRT-PCR. Moreover, circ_0019435 was more stable than its linear isoform-ABCC2. Besides, no regulation of circ_0019435 on ABCC2 and the chemoresistance of CC cells were found. Then, it was unveiled by a series of functional assays including colony formation, trypan blue staining, and transwell invasion assays in that circ_0019435 ablation induced the suppression of proliferation, invasion, and EMT of HeLa and SiHa cells. The subcellular distribution of circ_0019435 was assessed by subcellular fractionation and FISH assay. Furthermore, it was disclosed that circ_0019435 binds to EZH2 to silence DKK1 and PTEN. Finally, rescue assays corroborated that DKK1 and PTEN were involved in circ_0019435-mediated CC cell progression. In conclusion, circ_0019435 regulates DKK1 and PTEN expression at the epigenetic level, thereby influencing the progression of CC cells.

Interference with lncRNA NEAT1 promotes the proliferation, migration, and invasion of trophoblasts by upregulating miR-411-5p and inhibiting PTEN expression.

Background: Preeclampsia (PE) is an idiopathic hypertensive disorder of pregnancy, which is related to abnormal placental villi development. Our previous study has found that lncRNA NEAT1 promotes apoptosis of trophoblasts, but the role of NEAT1 in proliferation, migration, and invasion is still unclear. This study explores the role of NEAT1 in proliferation, migration, and invasion of trophoblasts.Methods: NEAT1 and miR-411-5p levels were detected by quantitative real-time PCR. Colony formation assay detected cell proliferation and transwell assay detected cell migration and invasion. Dual-luciferase reporter assay detected the binding between NEAT1 and miR-411-5p as well as the binding between miR-411-5p and PTEN. RNA pull-down assay detected the combination between NEAT1 and miR-411-5p.Result: NEAT1 was increased and miR-411-5p was reduced in PE patients and human trophoblasts (HTR8/SVneo cells) that were induced with H2O2. Interference with NEAT1 promoted cell proliferation, migration, and invasion, and the miR-411-5p inhibitor reversed the effect of siRNA-NEAT1. The expression of PTEN was promoted in PE patients and HTR8/SVneo cells that were induced with H2O2, while the miR-411-5p mimic inhibited PTEN expression, and the plasmid-mediated PTEN overexpression reversed the effect of the miR-411-5p mimic. Besides, under H2O2 induction, the miR-411-5p mimic promoted cell proliferation, migration, and invasion, and the plasmid-mediated PTEN overexpression reversed the effect of the miR-411-5p mimic.Conclusion: Interference with lncRNA NEAT1 promoted the proliferation, migration, and invasion of trophoblasts and alleviated the development of PE, which was partly mediated by upregulating miR-411-5p and inhibiting PTEN expression.

TUBB3 is associated with PTEN, neuroendocrine differentiation, and castration resistance in prostate cancer.

BACKGROUND: Tubulin-ß3 encoded by the Tubulin-ß3 (TUBB3) gene is a microtubule protein. Previous studies have shown that TUBB3 expression is upregulated in castration-resistant prostate cancer (CaP) and is involved in taxane resistance. However, the biological mechanism of TUBB3 involvement in the progression to castration-resistant CaP is not fully elucidated. This study aimed to analyze the expression and function of TUBB3 in localized and metastatic CaP. METHODS: TUBB3 expression was determined using immunohistochemistry in localized and metastatic CaP. We also investigated the association between TUBB3, phosphatase and tensin homolog (PTEN), and neuroendocrine differentiation and examined the involvement of TUBB3 in new antiandrogen drugs (enzalutamide and apalutamide) resistance in metastatic CaP. RESULTS: In 155 cases of localized CaP, immunohistochemistry showed that 5 (3.2%) of the CaP cases were positive for tubulin-ß3. Kaplan-Meier analysis showed that high expression of tubulin-ß3 was associated with poor prostate-specific antigen recurrence-free survival after radical prostatectomy. In 57 cases of metastatic CaP, immunohistochemistry showed that 14 (25%) cases were positive for tubulin-ß3. Tubulin-ß3 expression was higher in metastatic CaP than in localized CaP. High tubulin-ß3 expression was correlated with negative PTEN expression. TUBB3 expression was increased in neuroendocrine CaP based on several public databases. PTEN knockout decreased the sensitivity to enzalutamide and apalutamide in 22Rv-1 cells. TUBB3 knockdown reversed the sensitivity to enzalutamide and apalutamide in PTEN-CRISPR 22Rv-1 cells. High expression of tubulin-ß3 and negative expression of PTEN were significantly associated with poor overall survival in metastatic CaP treated with androgen deprivation therapy. CONCLUSIONS: These results suggest that TUBB3 may be a useful predictive biomarker for survival and play an essential role in antiandrogen resistance in CaP.

miR-139-5p promotes neovascularization in diabetic retinopathy by regulating the phosphatase and tensin homolog.

Pathological retinal neovascularization is a driver of the progression of diabetic retinopathy (DR). The present study sought to identify the microRNAs (miRNAs) that are differentially expressed during the progression of DR as well as to explore the specific regulatory mechanism of those miRNAs in retinal neovascularization. Using a microarray data set and a diabetic mouse model, it was determined that miR-139-5p was significantly upregulated during the progression of DR. The in vitro investigation revealed an elevation in the miR-139-5p level in both the high glucose (HG)-treated mouse retinal microvascular endothelial cells (mRMECs) and the HG-treated human RMECs (hRMECs). The miR-139-5p overexpression elevated cell migration, facilitated tube formation, and increased vascular endothelial growth factor (VEGF) protein level in the hRMECs. While the angiogenic effect of miR-139-5p overexpression was halted by an anti-VEGF antibody. Meanwhile, the miR-139-5p knockdown eliminated the VEGF-induced cell migration and tube formation in the hRMECs. The phosphatase and tensin homolog (PTEN) was the target gene of the miR-139-5p. PTEN overexpression removed the angiogenic effect of miR-139-5p overexpression, which led to reduced cell migration and tube formation. In the diabetic mice, the miR-139-5p antagomir effectively decreased the acellular capillaries and suppressed the formation of aberrant blood vessels in the retinal tissues. Taken together, miR-139-5p promotes retinal neovascularization by repressing PTEN expression.

Regulation of PTEN translation by PI3K signaling maintains pathway homeostasis.

The PI3K pathway regulates cell metabolism, proliferation, and migration, and its dysregulation is common in cancer. We now show that both physiologic and oncogenic activation of PI3K signaling increase the expression of its negative regulator PTEN. This limits the duration of the signal and output of the pathway. Physiologic and pharmacologic inhibition of the pathway reduces PTEN and contributes to the rebound in pathway activity in tumors treated with PI3K inhibitors and limits their efficacy. Regulation of PTEN is due to mTOR/4E-BP1-dependent control of its translation and is lost when 4E-BP1 is deleted. Translational regulation of PTEN is therefore a major homeostatic regulator of physiologic PI3K signaling and plays a role in reducing the pathway activation by oncogenic PIK3CA mutants and the antitumor activity of PI3K pathway inhibitors. However, pathway output is hyperactivated in tumor cells with coexistent PI3K mutation and loss of PTEN function.

Berberine regulates the Notch1/PTEN/PI3K/AKT/mTOR pathway and acts synergistically with 17-AAG and SAHA in SW480 colon cancer cells.

CONTEXT: Berberine (BBR) is used to treat diarrhoea and gastroenteritis in the clinic. It was found to have anticolon cancer effects. OBJECTIVE: To study the anticolon cancer mechanism of BBR by connectivity map (CMAP) analysis. MATERIALS AND METHODS: CMAP based mechanistic prediction was conducted by comparing gene expression profiles of 10 µM BBR treated MCF-7 cells with that of clinical drugs such as helveticoside, ianatoside C, pyrvinium, gossypol and trifluoperazine. The treatment time was 12 h and two biological replications were performed. The DMSO-treated cells were selected as a control. The interaction between 100 µM BBR and target protein was measured by cellular thermal shift assay. The protein expression of 1-9 µM BBR treated SW480 cells were measured by WB assay. Apoptosis, cell cycle arrest, mitochondrial membrane potential (MMP) of 1-9 µM BBR treated SW480 cells were measured by flow cytometry and Hoechst 33342 staining methods. RESULTS: CMAP analysis found 14 Hsp90, HDAC, PI3K or mTOR protein inhibitors have similar functions with BBR. The experiments showed that BBR inhibited SW480 cells proliferation with IC50 of 3.436 µM, induced apoptosis, autophage, MMP depolarization and arrested G1 phase of cell cycle at 1.0 µM. BBR dose-dependently up-regulated PTEN, while inhibited Notch1, PI3K, Akt and mTOR proteins at 1.0-9.0 µM (p < 0.05). BBR also acted synergistically with Hsp90 and HDAC inhibitor (0.01 µM) in SW480 cells at 0.5 and 1.0 µM. DISCUSSION AND CONCLUSIONS: The integrative gene expression-based chemical genomic method using CMAP analysis may be applicable for mechanistic studies of other multi-targets drugs.

Activation of metabotropic glutamate receptor 4 regulates proliferation and neural differentiation in neural stem/progenitor cells of the rat subventricular zone and increases phosphatase and tensin homolog protein expression.

Neural stem/progenitor cells (NSPCs) persist in the mammalian subventricular zone throughout life, where they can be activated in response to physiological and pathophysiological stimuli. A recent study indicates metabotropic glutamate receptor 4 (mGluR4) is involved in regulating NSPCs behaviors. Therefore, defining mGluR4 function in NSPCs is necessary for determining novel strategies to enhance the intrinsic potential for brain regeneration after injuries. In this study, mGluR4 was functionally expressed in SVZ-derived NSPCs from male Sprague-Dawley rats, in which the cyclic adenosine monophosphate concentration was reduced after treatment with the mGluR4-specific agonist VU0155041. Additionally, lateral ventricle injection of VU0155041 significantly decreased 5-bromo-2'-deoxyuridine (BrdU)+ and Ki67+ cells, while increased Doublecortin (DCX)/BrdU double-positive cells in SVZ. In cultured NSPCs, mGluR4 activation decreased the ratio of BrdU+ cells, G2/M-phase cells, and inhibited Cyclin D1 expression, whereas it increased neuron-specific class III ß-tubulin (Tuj1) expression and the number of Tuj1, DCX, and PSA-NCAM-positive cells. However, pharmacological blocking mGluR4 with the antagonist MSOP or knockdown of mGluR4 abolished the effects of VU0155041 on NSPCs proliferation and neuronal differentiation. Further investigation demonstrated that VU0155041 treatment down-regulated AKT phosphorylation and up-regulated expression of the phosphatase and tensin homolog protein (PTEN) in NSPCs culture. Moreover VU0155041-induced proliferating inhibition and neuronal differentiating amplification in NSPCs were significantly hampered by VO-OHpic, a PTEN inhibitor. We conclude that activation of mGluR4 in SVZ-derived NSPCs suppresses proliferation and enhances their neuronal differentiation, and regulation of PTEN may be involved as a potential intracellular target of mGluR4 signal. Cover Image for this issue: https://doi.org/10.1111/jnc.15052.

Ortho-silicic acid enhances osteogenesis of osteoblasts through the upregulation of miR-130b which directly targets PTEN.

AIMS: Osteoporosis is considered a common skeletal disease. Ortho-silicic acid has been found to enhance the osteogenic differentiation of osteoblasts. However, the molecular mechanism of osteogenesis induced by ortho-silicic acid is still undefined totally. MicroRNAs (miRs) play a key role in osteogenesis of osteoblasts. This study investigated the role of miR-130b in promoting osteogenesis induced by ortho-silicic acid. MAIN METHODS AND KEY FINDINGS: In this study, we found ortho-silicic acid enhanced osteogenesis of osteoblasts in vitro and promoted preventing and treating osteoporosis in vivo. Furthermore, the expression of miR-130b increased under application of ortho-silicic acid. In vitro, experiments demonstrated miR-130b overexpression or inhibition significantly promoted or suppressed osteogenic differentiation of osteoblasts under application of ortho-silicic acid, respectively. Consistently, downregulation of miR-130b in ovariectomy (OVX) rats dropped off the beneficial effect of ortho-silicic acid against bone loss. Mechanistically, we identified phosphatase and tensin homologue deleted on human chromosome 10 (PTEN) as the direct target of miR-130b during osteogenesis induced by ortho-silicic acid. SIGNIFICANCE: In conclusion, our findings reveal that ortho-silicic acid promotes the osteogenesis of osteoblasts mediated by the miR-130b/PTEN signaling axis, which identifies a new target to prevent and treat osteoporosis.

MicroRNA-144 promotes remote limb ischemic preconditioning-mediated neuroprotection against ischemic stroke via PTEN/Akt pathway.

Ischemic stroke is a refractory disease generally caused by cerebral ischemic injury. Remote ischemic preconditioning (RIPC) caused by transient ischemia and reperfusion of the femoral artery exerts a protective effect on ischemic stroke-induced brain injury. This study was designed to investigate the potential molecular mechanism of RIPC-mediated neuroprotection, namely, the biological effects of microRNA-144 on RIPC in mice with ischemic stroke and its effects on PTEN and Akt signaling pathways. Healthy adult C57BL6 mice were selected for the establishment of middle cerebral artery occlusion (MCAO). One hour before the start, remote ischemic preconditioning of limbs was performed in mice. Brain edema and infarct volume were measured. The expressions of microRNA-144, PTEN, and Akt were measured. The results showed that, compared with MCAO group, the RIPC group protected mice from cerebral ischemia-reperfusion injury, systemic accumulation of inflammatory cytokines, and accelerated apoptosis of parenchymal cells. In RIPC group, PTEN expression decreased, and mir-144 and Akt expression increased. The level of phosphorylated PTEN in the transfected microRNA-144 inhibitor group increased and the level of phosphorylated Akt reduced significantly. In conclusion, our results suggest that microRNA-144 may play a protective role in remote ischemic pretreatment by downregulating PTEN and upregulating Akt, suggesting that microRNA-144 via PTEN/Akt pathway may be of therapeutic significance in ischemic stroke.

Upregulation of PI3K/AKT/PTEN pathway is correlated with glucose and glutamine metabolic dysfunction during tamoxifen resistance development in MCF-7 cells.

Tamoxifen resistance is emerging as a big challenge in endocrine therapy of luminal A breast cancer patients. In this study, we aimed to determine the molecular changes of PI3K/AKT/PTEN signaling pathway during tamoxifen-resistance development using gradually increased doses of tamoxifen in one model, while fixing tamoxifen treatment dose at 35 µM for several times in the second model. An upregulation of AKT/PI3K genes was noticed at 30 µM tamoxifen concentration in cells treated with a gradual increase of tamoxifen doses. In the second model, significant upregulation of AKT1 was seen in cells treated with 35 µM tamoxifen for three times. All genes studied showed a significant increase in expression in resistant cells treated with 50 µM and 35 µM six times tamoxifen. These genes' upregulation was accompanied by PTEN and GSK3 ß genes' down-regulation, and it was in correlation to the changes in the metabolic rate of glucose in tamoxifen-resistant models. A significant increase in glucose consumption rate from culture media was observed in tamoxifen resistant cells with the highest consumption rate reported in the first day of culturing. Increased glucose consumption rates were also correlated with GLUL significant gene expression and non-significant change in c-MYC gene expression that may lead to increased endogenous glutamine synthesis. As a result, several molecular and metabolic changes precede acquired tamoxifen resistance could be used as resistance biomarkers or targets to reverse tamoxifen resistance.

WDHD1 is essential for the survival of PTEN-inactive triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is the most aggressive type of breast cancer that lacks the oestrogen receptor, progesterone receptor and human epidermal growth factor receptor 2, making it difficult to target therapeutically. Targeting synthetic lethality is an alternative approach for cancer treatment. TNBC shows frequent loss of phosphatase and tensin homologue (PTEN) expression, which is associated with poor prognosis and treatment response. To identify PTEN synthetic lethal interactions, TCGA analysis coupled with a whole-genome siRNA screen in isogenic PTEN-negative and -positive cells were performed. Among the candidate genes essential for the survival of PTEN-inactive TNBC cells, WDHD1 (WD repeat and high-mobility group box DNA-binding protein 1) expression was increased in the low vs. high PTEN TNBC samples. It was also the top hit in the siRNA screen and its knockdown significantly inhibited cell viability in PTEN-negative cells, which was further validated in 2D and 3D cultures. Mechanistically, WDHD1 is important to mediate a high demand of protein translation in PTEN-inactive TNBC. Finally, the importance of WDHD1 in TNBC was confirmed in patient samples obtained from the TCGA and tissue microarrays with clinic-pathological information. Taken together, as an essential gene for the survival of PTEN-inactive TNBC cells, WDHD1 could be a potential biomarker or a therapeutic target for TNBC.

CircPSMC3 alleviates the symptoms of PCOS by sponging miR-296-3p and regulating PTEN expression.

Polycystic ovary syndrome (PCOS), the most common female endocrine disease that causes anovulatory infertility, still lacks promising strategy for the accurate diagnosis and effective therapeutics of PCOS attributed to its unclear aetiology. In this study, we determined the abnormal reduction in circPSMC3 expression by comparing the ovarian tissue samples of PCOS patients and normal individuals. The symptom relief caused by up-regulation of circPSMC3 in PCOS model mice suggested the potential for further study. In vitro functional experiments confirmed that circPSMC3 can inhibit cell proliferation and promote apoptosis by blocking the cell cycle in human-like granular tumour cell lines. Mechanism study revealed that circPSMC3 may play its role through sponging miR-296-3p to regulate PTEN expression. Collectively, we preliminarily characterized the role and possible insights of circPSMC3/miR-296-3p/PTEN axis in the proliferation and apoptosis of KGN cells. We hope that this work provides some original and valuable information for the research of circRNAs in PCOS, not only to better understand the pathogenesis but also to help provide new clues for seeking for the future therapeutic target of PCOS.