Sequence-Guided Localization of DNA Hybridization Enables Highly Selective and Robust Genotyping.

Genetic variations are always related to human diseases or susceptibility to therapies. Nucleic acid probes that precisely distinguish closely related sequences become an indispensable requisite both in research and clinical applications. Here, a Sequence-guided DNA LOCalization for leaKless DNA detection (SeqLOCK) is introduced as a technique for DNA hybridization, where the intended targets carrying distinct "guiding sequences" act selectively on the probes. In silicon modeling, experimental results reveal considerable agreement (R2  = 0.9228) that SeqLOCK is capable of preserving high discrimination capacity at an extraordinarily wide range of target concentrations. Furthermore, SeqLOCK reveals high robustness to various solution conditions and can be directly adapted to nucleic acid amplification techniques (e.g., polymerase chain reaction) without the need for laborious pre-treatments. Benefiting from the low hybridization leakage of SeqLOCK, three distinct variations with a clinically relevant mutation frequency under the background of genomic DNA can be discriminated simultaneously. This work establishes a reliable nucleic acid hybridization strategy that offers great potential for constructing robust and programmable systems for molecular sensing and computing.

Exosomal miR-222-3p contributes to castration-resistant prostate cancer by activating mTOR signaling.

Despite the clinical benefits of androgen deprivation therapy, most patients with advanced androgen-dependent prostate cancer (ADPC) eventually relapse and progress to lethal androgen-independent prostate cancer (AIPC), also termed castration-resistant prostate cancer (CRPC). MiRNAs can be packaged into exosomes (Exos) and shuttled between cells. However, the roles and mechanisms of exosomal miRNAs involved in CRPC progression have not yet been fully elucidated. Here, we find that miR-222-3p is elevated in AIPC cells, which results in remarkable enhancement of cell proliferation, migration, and invasion ability. Furthermore, Exos released by AIPC cells can be uptaken by ADPC cells, thus acclimating ADPC cells to progressing to more aggressive cell types in vitro and in vivo through exosomal transfer of miR-222-3p. Mechanistically, Exos-miR-222-3p promoted ADPC cells transformed to AIPC-like cells, at least in part, by activating mTOR signaling through targeting MIDN. Our results show that AIPC cells secrete Exos containing miRNA cargo. These cargos can be transferred to ADPC cells through paracrine mechanisms that have a strong impact on cellular functional remodeling. The current work underscores the great therapeutic potential of targeting Exo miRNAs, either as a single agent or combined with androgen receptor pathway inhibitors for CRPC treatment.

How to better select SARS-CoV-2 preservation solution of virus nucleic acid testing.

BACKGROUND: Sampling and testing for SARS-CoV-2 is a widely recognized method for identifying patients with COVID-19. However, there is limited research available on the stability of nucleic acids in viral storage solutions. METHODS: This paper investigates the components that provide better protection for virus and nucleic acid detection. The study utilized real-time quantitative fluorescent PCR to detect SARS-CoV-2 and evaluate the preservation effect and stability of SARS-CoV-2 viral storage solution under various conditions, including different guanidinium salts, brands, and storage conditions. RESULTS: All brands of inactivated virus preservation solutions demonstrated effective preservation and stability. However, 0.5 mol/L guanidine hydrochloride and guanidine isothiocyanate solutions exhibited poor antiseptic effects. Additionally, refrigerated storage showed better preservation compared to room temperature storage. CONCLUSIONS: We recommend using inactivated virus collection solution to preserve and transport samples and testing preferably within 6 hours to reduce false negatives of NAT results.

The rs9402373 polymorphism of CTGF gene may not be related to inflammatory bowel disease susceptibility in Chinese population based on ARMS-PCR genotyping.

Background: It has been confirmed that the connective tissue growth factor (CTGF) gene rs9402373 polymorphism is associated with fibrotic and inflammatory diseases. However, studies on the relationship between polymorphisms in CTGF rs9402373 and inflammatory bowel disease (IBD) remain rare. Therefore, the aim of this study was to assess the association between the CTGF rs9402373 polymorphism and IBD susceptibility in a Chinese population. Materials and methods: To establish an amplification refractory mutation system (ARMS) PCR technology for genotyping CTGF gene rs9402373 polymorphism, we designed two specific forward primers for the wild and mutant types by placing the allele-specific nucleotide at the penultimate position of the '3' end of the primer. Then, 10 samples were randomly selected and rechecked by DNA sequencing to verify the accuracy of this method. We further used the established method to detect specimens collected from 191 patients with inflammatory bowel disease, including 120 Crohn's disease (CD) and 71 ulcerative colitis (UC), and 110 healthy Han Chinese individuals. Results: We successfully established the ARMS-PCR method for genotyping, and the results of 10 randomly selected samples were completely consistent with DNA sequencing. The rs9402373 G allele frequencies in UC and CD cases were 38.03% and 43.75%, respectively, and in controls, they were 41.82%. No significant difference was found in minor allele frequencies between the UC or CD and control groups (P = 0.473, P = 0.676). Genotype analysis demonstrated that there was no relationship between CTGF rs9402373 polymorphism and the risk of IBD regardless of the inheritance mode (P > 0.05). Conclusions: In this preliminary study, we successfully developed a simple, efficient and cost-effective method for genotyping CTGF rs9402373 polymorphism. The polymorphism may not be related to IBD susceptibility in the Chinese Han population.

New insights into lipid metabolism and prostate cancer (Review).

Prostate cancer (PCa) is the most common malignant tumor of the male urological system and poses a severe threat to the survival of middle­aged and elderly males worldwide. The development and progression of PCa are affected by a variety of biological processes, including proliferation, apoptosis, migration, invasion and the maintenance of membrane homeostasis of PCa cells. The present review summarizes recent research advances in lipid (fatty acid, cholesterol and phospholipid) metabolic pathways in PCa. In the first section, the metabolism of fatty acids is highlighted, from formation to catabolism and associated proteins. Subsequently, the role of cholesterol in the pathogenesis and evolution of PCa is described in detail. Finally, the different types of phospholipids and their association with PCa progression is also discussed. In addition to the impact of key proteins of lipid metabolism on PCa growth, metastasis and drug resistance, the present review also summarizes the clinical value of fatty acids, cholesterol and phospholipids, as diagnostic and prognostic indicators and therapeutic targets in PCa.

Gestational diabetes mellitus in the COVID-19 pandemic: A retrospective study from Hangzhou, China.

AIMS: Our study aimed to investigate changes in the prevalence of gestational diabetes mellitus (GDM) in the COVID-19 pandemic and postpandemic era and the risk of adverse pregnancy outcomes in pregnant women diagnosed with GDM during the blockade period. METHODS: First, we investigated changes in the prevalence of GDM and the population undergoing oral glucose tolerance tests (OGTT) after the COVID-19 pandemic. We then collected clinical information from pregnant women diagnosed with GDM to explore the risk of adverse pregnancy outcomes in pregnant women with GDM during the COVID-19 pandemic. RESULTS: After the COVID-19 pandemic, the proportion of pregnant women in the total number of outpatient OGTT tests decreased yearly. The ratio was 81.30%, 79.71%, and 75.48% from 2019 to 2021, respectively, with the highest proportion of pregnant women in February 2020 (92.03%). The prevalence of GDM was higher in March 2020 compared to the same period in 2019. However, from 2019 to 2021, the prevalence decreased year by year with 21.46%, 19.81%, and 18.48%, respectively. The risk of adverse pregnancy outcomes for pregnant women diagnosed with GDM during the most severe period of the COVID-19 pandemic did not differ from before the COVID-19 pandemic. CONCLUSIONS: After the COVID-19 pandemic, the prevalence of GDM increased during the most severe period of the epidemic, but the overall prevalence of GDM decreased year by year. In addition, the pandemic did not change the risk of adverse pregnancy outcomes in pregnant women with GDM.

Identification and Validation of Three Hub Genes Involved in Cell Proliferation and Prognosis of Castration-Resistant Prostate Cancer.

Background: The acquisition of castration resistance is lethal and inevitable in most prostate cancer patients under hormone therapy. However, effective biomarkers and therapeutic targets for castration-resistant prostate cancer remain to be defined. Methods: Comprehensive bioinformatics tools were used to screen hub genes in castration-resistant prostate cancer and were verified in androgen-dependent prostate cancer and castration-resistant prostate cancer in TCGA and the SU2C/PCF Dream Team database, respectively. Gene set enrichment analysis and in vitro experiments were performed to determine the potential functions of hub genes involved in castration-resistant prostate cancer progression. Results: Three hub genes were screened out by bioinformatics analysis: MCM4, CENPI, and KNTC1. These hub genes were upregulated in castration-resistant prostate cancer and showed high diagnostic and prognostic value. Moreover, the expression levels of the hub genes were positively correlated with neuroendocrine prostate cancer scores, which represent the degree of castration-resistant prostate cancer aggression. Meanwhile, in vitro experiments confirmed that hub gene expression was increased in castration-resistant prostate cancer cell lines and that inhibition of hub genes hindered cell cycle transition, resulting in suppression of castration-resistant prostate cancer cell proliferation, which confirmed the gene set enrichment analysis results. Conclusions: MCM4, CENPI, and KNTC1 could serve as candidate diagnostic and prognostic biomarkers of castration-resistant prostate cancer and may provide potential preventive and therapeutic targets.

[Corrigendum] RON and c­Met facilitate metastasis through the ERK signaling pathway in prostate cancer cells.

Subsequently to the publication of the above article, the authors have discovered that the version of Fig. 5 included in the paper was an incorrect version, and that two pairs of data panels were inadvertently included in Fig. 6D (the data panels for the NC+migration and NC+HGF+U0126+invasion experiments for the PC3 cells, and the data panels for the NC+invasion and NC+HGF+U0126+invasion experiments for the DU145 cells) that contained overlapping data derived from the same source. These data were intended to represent the results obtained under different experimental conditions. Furthermore, the GAPDH control bands in Fig. 4A (DU145 cells) and the p­ERK1/2 bands in Fig. 6A (PC3 cells) were incorrectly chosen for these figures. After having consulted the original data, the authors discovered that unintended errors were made in assembling the data for these graphs. In uploading the corrected version of Fig. 5, Fig. 3C and D and Fig. 4C and D were adjusted accordingly. The corrected versions of Figs. 3, 4, 5, and 6 are shown on the subsequent pages. The authors regret the errors that were made during the preparation of the published figures, and confirm that these errors did not affect the conclusions reported in the study. The authors are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish a Corrigendum, and all the authors agree to this Corrigendum. Furthermore, they apologize to the readership for any inconvenience caused. [Oncology Reports 37: 3209­3218, 2017; DOI: 10.3892/or.2017.5585].

Emerging Proteins in CRPC: Functional Roles and Clinical Implications.

Prostate cancer (PCa) is the most common cancer in men in the western world, but the lack of specific and sensitive markers often leads to overtreatment of prostate cancer which eventually develops into castration-resistant prostate cancer (CRPC). Novel protein markers for diagnosis and management of CRPC will be promising. In this review, we systematically summarize and discuss the expression pattern of emerging proteins in tissue, cell lines, and serum when castration-sensitive prostate cancer (CSPC) progresses to CRPC; focus on the proteins involved in CRPC growth, invasion, metastasis, metabolism, and immune microenvironment; summarize the current understanding of the regulatory mechanisms of emerging proteins in CSPC progressed to CRPC at the molecular level; and finally summarize the clinical applications of emerging proteins as diagnostic marker, prognostic marker, predictive marker, and therapeutic marker.

Laboratory management for large-scale population screening for SARS-CoV-2.

INTRODUCTION: The aim of this study was to investigate the improvements in laboratory testing procedures and the quality and safety management for large-scale population screening for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: Because of epidemic prevention and control needs in Hebei Province, on January 7, 2021, the Health Commission of Zhejiang Province sent a medical team to Hebei Province, to carry out SARS-CoV-2 nucleic acid testing. Screening for the SARS-CoV-2 nucleic acid test was performed using reverse-transcription polymerase chain reaction (RT-PCR). Practical tests and repeated process optimization were adopted to explore the optimal solution for improving laboratory testing procedures and the quality of and safety management for large-scale population screening for SARS-CoV-2. RESULTS: The Zhejiang medical team completed 250,000 pooled SARS-CoV-2 nucleic acid samples in 24 days in Shijiazhuang, with a peak daily testing capacity of 40,246 samples testing. There were no false-negative or false-positive results, and no laboratory personnel was infected with SARS-CoV-2. Significant achievements have been made in SARS-CoV-2 prevention and control. CONCLUSIONS: This report summarizes the effort of the medical team regarding their management of the quality and safety of laboratory tests and proposes corresponding empirical recommendations to provide a reference for future large-scale population screening SARS-CoV-2.

High concentrations of hypochlorous acid-based disinfectant in the environment reduced the load of SARS-CoV-2 in nucleic acid amplification testing.

During the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic, chlorine-containing disinfectants have been widely used in nucleic acid amplification testing laboratories. Whether the use of disinfectants affect the results of viral nucleic acid amplification is unknown. We examined the impact of different hypochlorous acid (HOCl) concentrations on the quantitative results of SARS-CoV-2 by real-time reverse-transcription polymerase chain reaction (RT-PCR). We also explored the mechanisms and models of action of chlorine-containing disinfectants that affected the detection of SARS-CoV-2. The results showed that different HOCl concentrations and different action times had an impact on the SARS-CoV-2 results. High concentrations of ambient HOCl have a greater impact than low concentrations, and this effect will increase with the extension of the action time and with the increase in ambient humidity. Compared with the enzymes or the extracted RNA required for RT-PCR, the impact of HOCl on the SARS-CoV-2 detection is more likely to be caused by damage to primers and probes in the PCR system. The false negative result still existed after changing the ambient disinfectant to ethanol but not peracetic acid. The use of HOCl in the environment will have an unpredictable impact on the nucleic acid test results of SARS-CoV-2. In order to reduce the possibility of false negative of SARS-CoV-2 nucleic acid test and prevent the spread of epidemic disease, environmental disinfectants should be used at the beginning and end of the experiment rather than during the experimental operation.

The MYH9 Cytoskeletal Protein Is a Novel Corepressor of Androgen Receptors.

In the progression of castration-resistant prostate cancer (CRPC), the androgen receptor (AR) that serves as a transcription factor becomes the most remarkable molecule. The transcriptional activity of AR is regulated by various coregulators. As a result, altered expression levels, an aberrant location or activities of coregulators promote the development of prostate cancer. We describe herein results showing that compared with androgen-dependent prostate cancer (ADPC) cells, AR nuclear translocation capability is enhanced in androgen-independent prostate cancer (AIPC) cells. To gain insight into whether AR coregulators are responsible for AR translocation capability, we performed coimmunoprecipitation (CO-IP) coupled with LC-MS/MS to screen 27 previously reported AR cofactors and 46 candidate AR cofactors. Furthermore, one candidate, myosin heavy chain 9 (MYH9), was identified and verified as a novel AR cofactor. Interestingly, the distribution of MYH9 was in both the cytoplasmic and nuclear compartments yet was enriched in the nucleus when AR was knocked down by AR shRNA, suggesting that the nuclear translocation of MYH9 was negatively regulated by AR. In addition, we found that blebbistatin, an inhibitor of MYH9, not only promoted AR nuclear translocation but also enhanced the expression of the AR target gene PSA, which indicates that MYH9 represses nuclear AR signaling. Taken together, our findings reveal that MYH9 appears to be a novel corepressor of AR plays a pivotal role in the progression of CRPC.

Elevated systemic immune inflammation index level is associated with disease activity in ulcerative colitis patients.

BACKGROUND: It has been confirmed that high Systemic immune-inflammation index (SII) levels usually indicate poor outcomes in various diseases, especially on malignancies. However, the clinical significance of the SII in ulcerative colitis (UC) patients is remain unclear. Therefore, the purpose of our paper is to analyze the levels of SII in UC patients and assess the relationship between the SII and disease activity. MATERIALS AND METHODS: We studied 187 consecutive patients with UC and 185 age- and sex-matched healthy controls retrospectively. The Mayo scoring system was adopted to evaluate disease activity in UC patients. We collected clinical characteristics and laboratory parameters from hospital electronic medical records. RESULTS: The SII levels were significantly higher in UC patients than those in healthy subjects (P < 0.001). Higher SII levels were observed in moderate and severe UC subgroups compared to mild or remission subgroups. Correlation analysis displayed that the SII levels were positively relatived with Mayo score (r = 0.469, P < 0.001), C reactive protein (CRP) (r = 0.480, P < 0.001), and erythrocyte sedimentation rate (ESR) (r = 0.336, P < 0.001), but negatively with haemoglobin (Hb) (r = -0.271, P < 0.001). A multiple linear regression analysis suggested that there was an independent correlation between Mayo score and SII (beta = 0.324, t = 4.241, P < 0.001). The receiver operating characteristic (ROC) curve revealed that the maximum area under the curve (AUC) was 0.711 (95% CI, 0.630-0.791, P < 0.001), and the cut-off value for diagnosing active UC was 485.95, the sensitivity was 0.641, and the specificity was 0.75. CONCLUSIONS: We demonstrated that the SII was elevated significantly in UC patients and was closely related to the UC disease activity. In addition, the SII had a high discriminative capacity for active UC.

Integrated profiling identifies SLC5A6 and MFAP2 as novel diagnostic and prognostic biomarkers in gastric cancer patients.

Gastric cancer (GC) is one of the leading causes of malignancy­associated mortality worldwide. However, the underlying molecular mechanisms of GC are unclear and the prognosis of GC is poor. Therefore, it is important and urgent to explore the underlying mechanisms and screen for novel diagnostic and prognostic biomarkers, as well as therapeutic targets. In the current study, scale­free gene co­expression networks were constructed using weighted gene co­expression network analysis, the potential associations between gene sets and clinical features were investigated, and the hub genes were identified. The gene expression profiles of GSE38749 were downloaded from the Gene Expression Omnibus database. RNA­seq and clinical data for GC from The Cancer Genome Atlas were utilized for verification. Furthermore, the expression of candidate biomarkers in gastric tissues was investigated. Survival analysis was performed using Kaplan­Meier and log­rank test. The predictive role of candidate biomarkers in GC was evaluated using a receiver operator characteristic (ROC) curve. Gene Ontology, gene set enrichment analysis and gene set variation analysis methods were used to interpret the function of candidate biomarkers in GC. A total of 29 modules were identified via the average linkage hierarchical clustering. A significant module consisting of 48 genes associated with clinical traits was found; three genes with high connectivity in the clinical significant module were identified as hub genes. Among them, SLC5A6 and microfibril­associated protein 2 (MFAP2) were negatively associated with the overall survival, and their expression was elevated in GC compared with non­tumor tissues. Additionally, ROC curves indicated that SLC5A6 and MFAP2 showed a good diagnostic power in discriminating cancerous from normal tissues. SLC5A6 and MFAP2 were identified as novel diagnostic and prognostic biomarkers in GC patients; both of these genes were first reported here in connection with GC and deserved further research.

SGK1 in Human Cancer: Emerging Roles and Mechanisms.

Serum and glucocorticoid-induced protein kinase 1 (SGK1) is a member of the "AGC" subfamily of protein kinases, which shares structural and functional similarities with the AKT family of kinases and displays serine/threonine kinase activity. Aberrant expression of SGK1 has profound cellular consequences and is closely correlated with human cancer. SGK1 is considered a canonical factor affecting the expression and signal transduction of multiple genes involved in the genesis and development of many human cancers. Abnormal expression of SGK1 has been found in tissue and may hopefully become a useful indicator of cancer progression. In addition, SGK1 acts as a prognostic factor for cancer patient survival. This review systematically summarizes and discusses the role of SGK1 as a diagnostic and prognostic biomarker of diverse cancer types; focuses on its essential roles and functions in tumorigenesis, cancer cell proliferation, apoptosis, invasion, metastasis, autophagy, metabolism, and therapy resistance and in the tumor microenvironment; and finally summarizes the current understanding of the regulatory mechanisms of SGK1 at the molecular level. Taken together, this evidence highlights the crucial role of SGK1 in tumorigenesis and cancer progression, revealing why it has emerged as a potential target for cancer therapy.

High mean platelet volume-to-platelet count ratio as a diagnostic maker for increased risk of liver function damage in pediatric patients with infectious mononucleosis in China.

The aim of the present study was to provide novel laboratory indexes for infectious mononucleosis (IM) in pediatric patients. In the present prospective study, a total of 141 pediatric patients with IM and 146 healthy subjects were enrolled. The white blood cell count (WBC), red blood cell count (RBC), hemoglobin (HB), platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transferase (GGT), uric acid (UA), urea, creatinine, total cholesterol (TC) and triglycerides (TG) in peripheral blood were evaluated. WBC, ALT, AST, GGT, UA, TG, MPV and the MPV/PLT ratio in the patients were significantly higher compared with those in the controls (P<0.01), while RBC, HB, urea, TC, PLT and PDW were significantly lower in the patients (P<0.05 for PDW and P<0.01 for others). Regression analysis under stepwise adjustment indicated that PLT and MPV/PLT were significantly associated with IM (P<0.01). Furthermore, MPV/PLT was positively correlated with ALT, AST, GGT, UA and TC (P≤0.01). In the receiver operating characteristic analysis, a sensitivity of 83.7% and specificity of 76.0% regarding the prediction of IM in pediatric patients using the MPV/PLT ratio was achieved at the cutoff of MPV/PLT(%)=3.42. In conclusion, the MPV/PLT ratio may be a novel diagnostic indicator for pediatric IM and indirectly predict damage to liver function.

The prognosis value of EphA3 and the androgen receptor in prostate cancer treated with radical prostatectomy.

BACKGROUND: This study aimed to preliminarily assess the relationship between erythropoietin-producing hepatocellular carcinoma receptor A3 (EphA3) and androgen receptor (AR) protein expression levels and prognosis in prostate cancer (PCa) to better understand the role of EphA3 in the prognosis and progression of PCa. MATERIALS: We investigated the expression of EphA3 and AR in human PCa by immunohistochemistry. RESULTS: EphA3 and AR were both significantly upregulated in PCa, with expression mainly localized to the nucleus. A high level of AR expression was found in 48.4% of 64 tumor samples, which was significantly more than in the adjacent tissue samples (15.6%) (P < 0.01). The percentage of samples expressing a high level of EphA3 was significantly greater in the PCa samples (54.7%) than in the adjacent tissue samples (20.3%) for the 64 tumors (P < 0.01). The high levels of EphA3 and AR expression in the PCa tissue samples were both correlated with the pathological stage, bladder and rectal invasion, distant metastasis, and preoperative PSA level (both P < 0.05). The survival time was significantly shorter in high levels of AR expression of patients. (P < 0.01). A high level of EphA3 in PCa patients suggests a poor prognosis (P < 0.05). Biochemical recurrence, distant metastasis, and the final scores of EphA3 and AR expression were significantly correlated with the prognosis of PCa (P < 0.05). CONCLUSIONS: Increased EphA3 expression is an independent prognostic factor for a poor outcome and decreased survival in PCa.

SGK1 inhibition-induced autophagy impairs prostate cancer metastasis by reversing EMT.

BACKGROUND: Despite SGK1 has been identified and characterized as a tumor-promoting gene, the functions and underlying mechanisms of SGK1 involved in metastasis regulation have not yet been investigated in cancer. METHODS: We investigated the cellular responses to GSK650394 treatment and SGK1 silencing (or overexpression) in human prostate cancer (PCa) cell lines and PC3 xenografts by wound healing assay, migration and invasion assay, western blotting, immunofluorescence and immunohistochemistry. RESULTS: In the present study, we found that SGK1 expression positively correlates with human prostate cancer (PCa) progression and metastasis. We show that SGK1 inhibition significantly attenuates EMT and metastasis both in vitro and in vivo, whereas overexpression of SGK1 dramaticlly promoted the invasion and migration of PCa cells. Our further results suggest that SGK1 inhibition induced antimetastatic effects, at least partially via autophagy-mediated repression of EMT through the downregulation of Snail. Moreover, ectopic expression of SGK1 obviously attenuated the GSK650394-induced autophagy and antimetastatic effects. What's more, dual inhibition of mTOR and SGK1 enhances autophagy and leads to synergistic antimetastatic effects on PCa cells. CONCLUSIONS: Taken together, this study unveils a novel mechanism in which SGK1 functions as a tumor metastasis-promoting gene and highlights how co-targeting SGK1 and autophagy restrains cancer progression due to the amplified antimetastatic effects.

SGK1 inhibition induces autophagy-dependent apoptosis via the mTOR-Foxo3a pathway.

BACKGROUND: Although inhibition of SGK1 has been shown to delay cancer progression, the underlying mechanisms have not yet been elucidated. METHODS: We investigated the cellular responses to GSK650394 treatment and SGK1 silencing (or overexpression) in human prostate cancer (PCa) cell lines and PC3 xenografts by flow cytometry, western blotting, immunofluorescence, transmission electron microscopy and immunohistochemistry. RESULTS: In the present study, we demonstrated that SGK1 inhibition, mediated by either GSK650394 or SGK1 shRNA, induced G2/M arrest, apoptosis and autophagy. Furthermore, 3MA-mediated autophagy inhibition attenuated SGK1 inhibition-induced apoptosis, suggesting that induction of autophagy precedes apoptosis. Moreover, ectopic expression of SGK1 significantly attenuated the GSK650394-induced effects. Suppression of mTOR and Foxo3a phosphorylation is critical for blockade of SGK1-induced autophagy and apoptosis, at least partially via pFoxo3a (S253)-LC3 and pFoxo3a (S253)-p27 interactions. Dual inhibition of mTOR and SGK1 enhances autophagy activation and leads to synergistic cytocidal effects in PCa cells. CONCLUSIONS: In summary, our findings show that SGK1 inhibition exhibits significant antitumour effects against PCa in vitro and in vivo. This study uncovered a novel mechanism of SGK1 inhibition in PCa, which is mediated, at least in part, by inducing autophagy-dependent apoptosis via the mTOR-Foxo3a pathway.