Copper exposure induces hepatic G0/G1 cell-cycle arrest through suppressing the Ras/PI3K/Akt signaling pathway in mice.

Copper (Cu), as a common chemical contaminant in environment, is known to be toxic at high concentrations. The current research demonstrates the effects of copper upon hepatocyte cell-cycle progression (CCP) in mice. Institute of cancer research (ICR) mice (n = 240) at an age of four weeks were divided randomly into groups treated with different doses of Cu (0, 4, 8, and 16 mg/kg) for 21 and 42 days. Results showed that high Cu exposure caused hepatocellular G0/G1 cell-cycle arrest (CCA) and reduced cell proportion in the G2/M phase. G0/G1 CCA occurred with down-regulation (p < 0.05) of Ras, p-PI3K (Tyr458), p-Akt (Thr308), p-forkhead box O3 (FOXO3A) (Ser253), p-glycogen synthase kinase 3-ß (GSK3-ß) (Ser9), murine double minute 2 (MDM2) protein, and mRNA expression levels, and up-regulation (p < 0.05) of PTEN, p-p53 (Ser15), p27, p21 protein, and mRNA expression levels, which subsequently suppressed (p < 0.05) the protein and mRNA expression levels of CDK2/4 and cyclin E/D. These results indicate that Cu exposure suppresses the Ras/PI3K/Akt signaling pathway to reduce the level of CDK2/4 and cyclin E/D, which are essential for the G1-S transition, and finally causes hepatocytes G0/G1 CCA.

The RAS-PI3K-AKT-NF-κB pathway transcriptionally regulates the expression of BCL2 family and IAP family genes and inhibits apoptosis in fibrous epulis.

BACKGROUND: Epulis has a tumor-like appearance but is considered to be a massive reactive lesion rather than a true neoplasia. Limited information about the pathogenesis of epulis is available. The purpose of our study was to identify potential signaling pathways in fibrous epulis through transcriptome profiling. METHODS: Differentially expressed genes (DEGs) between fibrous epulis lesions and normal gingival tissues were detected using RNA sequencing (RNAseq). The expression levels of eighteen genes were validated using quantitative real-time PCR (qRT-PCR). RESULTS: RNAseq identified 533 upregulated genes and 732 downregulated genes. The top 10 upregulated genes were IL11, OSM, MMP3, KRT75, MMP1, IL6, IL1B, IL24, SP7, and ADGRG3. The top 10 downregulated genes were BCHE, TYR, DCT, KRT222, RP11-507K12.1, COL6A5, PMP2, GFRA1, SCN7A, and CDH19. KEGG pathway analysis further indicated that the DEGs were enriched in "Pathways in cancer" and the "Ras signaling pathway". quantitative real-time PCR verified that the expression levels of SOS1, HRAS, PIK3CA, AKT3, IKBKA, IKBKB, NFKB1, BCL2, BCL2L1, XIAP, BIRC2, and BIRC3 were increased significantly. CONCLUSIONS: The current transcriptomic profiling study reveals that in fibrous epulis, RAS-PI3K-AKT-NF-κB pathway transcriptionally regulates the expression of BCL2 family and IAP family genes, leading to increased proliferation and apoptosis inhibition.

Retracted: Ras-PI3K-AKT signaling promotes the occurrence and development of uveal melanoma by downregulating H3K56ac expression.

BACKGROUND: Uveal melanoma (UM) is an intraocular malignant tumor characterized by rapid progression and recurrence. The current conventional treatments are unsatisfactory. Histone acetylation at H3 lysine 56 (H3K56ac) has been reported to be a tumor suppressor in breast cancer. However, whether H3K56ac prevents the occurrence and development of UM remains uninvestigated. The study aimed to explore the regulatory effect of H3K56ac on Ras-PI3K-AKT induced UM cells proliferation and migration. METHODS: The vectors of pEGFP-RasWT , pEGFP-K-Ras G12V/Y40C , and pEGFP-N1 were transfected into MP46 cells, and protein levels of phosphorylated AKT Ser473 and H3K56ac were examined using western blot analysis. The effect of H3K56ac on cell proliferation and migration were studied using 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide, colony formation, and Transwell assays. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and chromatin immunoprecipitation assays were performed to determine the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) downstream genes. Further, the regulatory effects of silent mating type information regulation 2 homolog-1 (SIRT1), general control nonderepressible 5 (GCN5), and mouse double minute 2 homolog (MDM2) on Ras-PI3K-AKT affected H3K56ac expression were also investigated. RESULTS: H3K56ac expression was specifically downregulated by Ras-PI3K-AKT activation pathway. H3K56ac inhibited the tumorigenic effect of Ras-PI3K-AKT on MP46 cells viability, colony formation, and migration, as well as participated in regulating the transcription of PI3K/AKT downstream genes. SIRT1 silence recovered H3K56ac expression, and reversed the tumorigenic effect of Ras-PI3K-AKT activation on MP46 cells. Downregulation of H3K56ac induced by Ras-PI3K-AKT activation was found to be associated with MDM2-mediated the degradation of GCN5. CONCLUSIONS: The results demonstrated that Ras-PI3K-AKT signaling promoted UM cells proliferation and migration via downregulation of H3K56ac expression, which might be related to MDM2-mediated the degradation of GCN5.

Guanine-Rich RNA Sequence Binding Factor 1 Deficiency Promotes Colorectal Cancer Progression by Regulating PI3K/AKT Signaling Pathway.

Background: Guanine-rich RNA sequence binding factor 1 (GRSF1), part of the RNA-binding protein family, is now attracting interest due to its potential association with the progression of a variety of human cancers. The precise contribution and molecular mechanism of GRSF1 to colorectal cancer (CRC) progression, however, have yet to be clarified. Methods: Immunohistochemistry and Western Blot analysis was carried out to detect the expression of GRSF1 in CRC at both mRNA and protein levels and its subsequent effects on prognosis. A series of functional tests were performed to understand its influence on proliferation, migration, and invasion of CRC cells. Results: The universal downregulation of GRSF1 in CRC was identified, indicating a correlation with poor prognosis. Our functional studies unveiled that the elimination of GRSF1 enhances tumour activities such as proliferation, migration, and invasion of CRC cells, while GRSF1 overexpression curtailed these abilities. Conclusion: Notably, we uncovered that GRSF1 insufficiency modulates the PI3K/Akt signaling pathway and Ras activation in CRC. Therefore, our data suggest GRSF1 operates as a tumor suppressor gene in CRC and may offer promise as a potential biomarker and novel therapeutic target in CRC management.

Aflatoxin B1 disrupts testicular development via the cell cycle-related Ras/PI3K/Akt signaling in mice and pig.

Aflatoxins B1 (AFB1), a type I carcinogen widely present in the environment, not only poses a danger to animal husbandry, but also poses a potential threat to human reproductive health, but its mechanism is still unclear. To address this question, multi-omics were performed on porcine Sertoli cells and mice testis. The data suggest that AFB1 induced testicular damage manifested as decreased expression of GJA1, ZO1 and OCCLUDIN in mice (p < 0.01) and inhibition of porcine Sertoli cell proliferation. Transcriptomic analysis suggested changes in noncoding RNA expression profiles that affect the cell cycle-related Ras/PI3K/Akt signaling pathway after AFB1 exposure both in mice and pigs. Specifically, AFB1 caused abnormal cell cycle of testis with the characterization of decreased expressions of CCNA1, CCNB1 and CDK1 (p < 0.01). Flow cytometry revealed that the G2/M phase was significantly increased after AFB1 exposure. Meanwhile, AFB1 downregulated the expressions of Ras, PI3K and AKT both in porcine Sertoli cell (p < 0.01) and mice testis (p < 0.01). Metabolome analysis verified the alterations in the PI3K/Akt signaling pathway (p < 0.05). Moreover, the joint analysis of metabolome and microbiome found that the changes of metabolites were correlated with the expression of flora. In conclusion, we have demonstrated that AFB1 impairs testicular development via the cell cycle-related Ras/PI3K/Akt signaling.

Piclamilast mitigates 1,2-dimethylhydrazine induced colon cancer in rats through modulation of Ras/PI3K/Akt/mTOR and NF-κß signaling.

Colorectal cancer (CRC) is the third leading type of adult cancer in both genders with high morbidity and mortality worldwide. Even though the discovery of many antineoplastic drugs for CRC, the current therapy is not adequately efficient.This study was designed to investigate the effect and mechanism of Piclamilast (PIC), a selective PDE4 inhibitor, on a DMH-induced colorectal cancer (CRC) rat model. The rats were grouped (n = 10) into group 1 (control), group 2 (PIC 3 mg/kg, p.o.), groups 3-5 received DMH (20 mg/kg/week, S.C.), and groups 4 and 5 received PIC (1 and 3 mg/kg/day, p.o.) for 15 weeks. The DMH treatment increased aberrant crypt foci (ACF), Proliferating cell nuclear antigen (PCNA), and TBARS levels, along with decreased antioxidant defenses (GSH, GSH-Px, and catalase). Increased NF-κß expression and inflammatory cytokines were also evident. PIC dose-dependently reduced ACF and restored oxidative stress and inflammatory markers favorably. Moreover, PIC in its large, tested dose only significantly increased the intracellular level of cAMP and suppressed the activation of Ras and PI3K and its downstream Akt/mTOR signaling. Furthermore, PIC promoted CRC apoptosis, and increased the gene expression of the apoptotic factors, caspase-3 and Bax, and decreased the anti-apoptotic factor Bcl-2. The results of this study show that PIC may be a promising therapeutic agent for the treatment of CRC. PIC might inhibit the proliferation of CRC cells and induce apoptosis via multiple mechanisms that involve its antioxidant effect and inhibition of NF-κß and Ras/PI3K/Akt/mTOR signaling.

FAM83H overexpression predicts worse prognosis and correlates with less CD8+ T cells infiltration and Ras-PI3K-Akt-mTOR signaling pathway in pancreatic cancer.

BACKGROUND: Family with sequence similarity 83 members H (FAM83H) is one member of Family with sequence similarity 83 (FAM83) family, which possess oncogenic properties in several types of cancer. However, the potential function of FAM83H in pancreatic cancer (PC) still remain unknown. AIM: This study aims to explore the role of FAM83H during pancreatic carcinogenesis and the regulation of immune infiltration in PC. METHODS: In the current study, the clinical significance and potential biological of FAM83H were evaluated by bioinformatics analysis. Possible associations between FAM83H expression and tumor immunity were analyzed using ESTIMATE algorithm and single-sample gene set enrichment analysis (ssGSEA). RESULTS: FAM83H expression was significantly upregulated in tumor tissues, and positively associated with higher histologic grade, tumor recurrence, and worse prognosis. FAM83H overexpression is notably associated with KRAS activation. And functional enrichment analysis demonstrated that FAM83H may be involved in positive regulation of cell proliferation and migration, Ras protein signal transduction, regulation of cell-matrix adhesion, epithelial to mesenchymal transition (EMT), TGF-ß receptor signaling in EMT, and activated NOTCH transmits signal to the nucleus. ESTIMATE algorithm and ssGSEA demonstrated that FAM83H overexpression suppressed the infiltration and antitumor activity of tumor-infiltrating lymphocytes (TILs), especially for CD8+ T cells. Besides, FAM83H overexpression significantly correlated with low expression of TIL-related gene markers (e.g. CD8A, CD8B, CD2, CD3D, and CD3E). CONCLUSION: The study suggests that FAM83H overexpression predicts poor prognosis and correlates with less CD8+ T cells infiltration and Ras-PI3K-Akt-mTOR signaling pathway in PC.

Anti-Inflammatory Effects of Huangqin Decoction on Dextran Sulfate Sodium-Induced Ulcerative Colitis in Mice Through Regulation of the Gut Microbiota and Suppression of the Ras-PI3K-Akt-HIF-1α and NF-κB Pathways.

OBJECTIVE: Huangqin decoction (HQD), a classical traditional Chinese medicinal formula, has been commonly used to treat gastrointestinal diseases for thousands of years. We investigated the anti-inflammatory effects and underlying mechanisms of HQD on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC). METHODS: Experimental mice were given 3% DSS, and HQD (2.275, 4.55, and 9.1 g/kg), or mesalazine (ME, 200 mg/kg) orally for 7 days. Body weight loss, disease activity index (DAI), colon length, histology, and levels of inflammatory cytokines were measured to evaluate the effects of HQD on colitis. The effects of HQD on the Ras-phosphoinositide-3-kinase (PI3K)-Akt-hypoxia inducible factor 1 alpha (HIF-1α) and nuclear factor-kappa B (NF-κB) pathways were evaluated by Western blot analysis. In addition, the gut microbiota was characterized using high-throughput Illumina MiSeq sequencing. RESULTS: The results showed that HQD significantly reduced the body weight loss, ameliorated DAI, restored colon length, and improved the intestinal epithelial cell barrier in mice with DSS-induced colitis. The messenger RNA (mRNA) expression levels of inflammatory mediators were decreased following HQD treatment. Furthermore, the Ras-PI3K-Akt-HIF-1α and NF-κB pathways were significantly inhibited by HQD. Finally, treatment with HQD resulted in recovery of gut microbiota diversity. CONCLUSIONS: HQD ameliorates DSS-induced colitis through regulation of the gut microbiota, and suppression of Ras-PI3K-Akt-HIF-1α and NF-κB pathways. Our results suggested that HQD may be a potential candidate for treatment of UC.

Des-gamma-carboxy prothrombin antagonizes the effects of Sorafenib on human hepatocellular carcinoma through activation of the Raf/MEK/ERK and PI3K/Akt/mTOR signaling pathways.

Despite significant progress, advanced hepatocellular carcinoma (HCC) remains an incurable disease, and the overall efficacy of targeted therapy by Sorafenib remains moderate. We hypothesized that DCP (des-gamma-carboxy prothrombin), a prothrombin precursor produced in HCC, might be one of the reasons linked to the low efficacy of Sorafenib. We evaluated the efficacy of Sorafenib in HLE and SK-Hep cells, both of which are known DCP-negative HCC cell lines. In the absence of DCP, Sorafenib effectively inhibited the growth of HCC and induced cancer cell apoptosis. In the presence of DCP, HCC was resistant to Sorafenib-induced inhibition and apoptosis, as determined by in vitro assays and in mice xenografted with HLE cells. Molecular analysis of HLE xenografted-nude mice showed that DCP activates the transduction of the Ras/Raf/MEK/ERK and Ras/PI3K/Akt/mTOR cascades. DCP might stimulate the formation of compensatory feedback loops in the intricately connected signaling pathways when kinases are targeted by Sorafenib. Our results indicate that DCP antagonizes the inhibitory effects of Sorafenib on HCC through activation of the Ras/Raf/MEK/ERK and Ras/PI3K/Akt/mTOR signaling pathways. Taken together, our findings define a DCP-mediated mechanism of inhibition of Sorafenib in HCC, which is critical for targeting therapy in advanced HCC.

Protective effect of microRNA-30b on hypoxia/reoxygenation-induced apoptosis in H9C2 cardiomyocytes.

We examined the protective role of microRNA-30b (miR-30b) in ischemia-reperfusion (I/R)-induced injury in rat H9C2 cardiomyocytes. H9C2 cells were subjected to hypoxia-reoxygenation (H/R) treatment to simulate ischemia-reperfusion (I/R) injury. H9C2 cells were divided into: vehicle control (VC) group; scrambled inhibitors (INC) group; scrambled mimics (MNC) group; H/R+VC group; H/R+INC group; H/R+mimics group. H/R induced apoptosis was detected by flow cytometry and the pathways involved in miR-30b-mediated protection were examined by analyzing the expression of miR-30b, Bcl-2, Bax, Caspase-3, KRAS, p-AKT and total AKT in H9C2 cells. Overexpression of miR-30b mimic (H/R+mimics group) significantly increased Bcl-2 and Bcl-2/Bax levels and decreased Bax and Caspase-3 levels, compared with the H/R+VC group (all P<0.05). Consistent with this, the apoptosis rate was significantly decreased in the H/R+mimics group (P<0.05) compared with the H/R+VC group. Western blot analysis revealed that overexpression of miR-30b mimic resulted in significantly increase in AKT activation and decreased KRAS, compared to the H/R+VC group (both P<0.05). In conclusion, the H/R induced apoptosis decreased miR-30b expression, but over-expression of miR-30b inhibited H/R induced apoptosis. The observed miR-30b-mediated protection against H/R induced apoptosis involved the upregulation of Ras-PI3K-Akt pathway.