Oncogenic NanogP8 expression regulates cell proliferation and migration through the Akt/mTOR signaling pathway in human gastric cancer - SGC-7901cell line

Coding, or non-coding, that is the question

The advent of high-throughput sequencing uncovered that our genome is pervasively transcribed into RNAs that are seemingly not translated into proteins. It was also found that non-coding RNA transcripts outnumber canonical protein-coding genes. This mindboggling discovery prompted a surge in non-coding RNA research that started unraveling the functional relevance of these new genetic units, shaking the classic definition of "gene". While the non-coding RNA revolution was still taking place, polysome/ribosome profiling and mass spectrometry analyses revealed that peptides can be translated from non-canonical open reading frames. Therefore, it is becoming evident that the coding vs non-coding dichotomy is way blurrier than anticipated. In this review, we focus on several examples in which the binary classification of coding vs non-coding genes is outdated, since the same bifunctional gene expresses both coding and non-coding products. We discuss the implications of this intricate usage of transcripts in terms of molecular mechanisms of gene expression and biological outputs, which are often concordant, but can also surprisingly be discordant. Finally, we discuss the methodological caveats that are associated with the study of bifunctional genes, and we highlight the opportunities and challenges of therapeutic exploitation of this intricacy towards the development of anticancer therapies.

Correlation of the AKT/mTOR signaling pathway with the clinicopathological features and prognosis of nasopharyngeal carcinoma

The primary aim of this study was to examine the correlation of the AKT/mTOR signaling pathway with the clinicopathological features and prognostic significance in nasopharyngeal carcinoma (NPC). The study tissues were collected from 285 patients with NPC and normal mucosal tissues were obtained from 289 individuals with normal nasopharynxes. Immunohistochemical staining was used to detected the expression of the AKT, mTOR, and p70 ribosomal S6 kinase (P70S6K) proteins. Follow-up was performed for between 8 and 60 months. Spearman’s rank correlation analysis was performed to evaluate the correlation of the expression of the AKT, mTOR, and P70S6K proteins in NPC tissues. Kaplan-Meier curves were plotted to show the survival of patients with NPC. A Cox proportional hazards model was used to explore the independent risk factors for prognosis. The expression of the AKT, mTOR, and P70S6K proteins in NPC tissues was higher than that in healthy nasopharyngeal mucosal tissues, and was correlated with T-staging, N-staging, clinical stage, distant metastasis, and differentiation. The positive expression of the AKT, mTOR, and P70S6K proteins was higher in patients with stage III/IV NPC, low differentiation, and metastasis. The survival rates of patients with NPC with AKT-positive, mTOR-positive, and P70S6K-positive expression were considerably lower than those without the expression of these proteins. Distant metastasis and the overexpression of the AKT, mTOR, and P70S6K proteins were independent risk factors for the prognosis of patients with NPC. The results obtained from this study indicated an association between the AKT/mTOR signaling pathway and the progression of NPC. The upregulation of the AKT/mTOR pathway in patients with NPC is a predictor of poor prognosis.

NANOGP8 expression regulates gastric cancer cell progression by transactivating DBC1 in gastric cancer MKN-45 cells

NANOGP8 is one of the NANOG pseudogenes and is expressed together with NANOG in multiple tumor tissues and cell lines. The biological functions of NANOGP8 in progression of gastric cancer are unclear. In the present study, the role of NANOGP8 was investigated in gastric cancer cells. The gathered data demonstrated that NANOG expression in both mRNA and protein was elevated in gastric cancer cell lines relative to a normal gastric epithelial cell line. Downregulation of NANOGP8 inhibited cell proliferation and increased apoptosis in human gastric carcinoma cell lines. Furthermore, silencing of NANOGP8 suppressed tumor growth in vivo. Interestingly, it was identified that deleted in breast cancer 1 (DBC1) expression was also markedly downregulated following NANOGP8 knockdown. DNA microarray and dual-luciferase assays further indicated that NANOGP8 may bind to the DBC1 promoter region and regulate DBC1 expression. Therefore, the gathered data provided evidence that NANOGP8 contributes to progression of gastric cancer via DBC1 and may have potential translational significance.

UNBS5162 inhibits proliferation of human melanoma cells by inducing apoptosis via the PI3K/Akt pathway

UNBS5162, a novel naphthalimide, is generated by UNBS3157 hydrolysis in physiological saline. In the present study, the effects of UNBS5162 on M14 human melanoma cells were evaluated by Cell Counting Kit‑8 and transwell assays, as well as western blotting. The underlying mechanism of apoptosis induced by UNBS5162 was investigated. The results demonstrated that proliferation of UNBS5162‑treated M14 melanoma cells was markedly inhibited in a time‑dependent manner. The flow cytometry results indicated a markedly increased apoptosis rate in the experimental group compared with in the control group (23.8±0.4 vs. 7.62±0.5%). Microscopy analysis revealed that the invasive and migratory abilities of UNBS5162‑treated M14 cells were markedly suppressed. Furthermore, UNBS5162 treatment led to decreased expression of the anti‑apoptotic protein B‑cell lymphoma 2, but increased expression of the pro‑apoptotic proteins Bcl‑2‑associated X protein and caspase‑3. In addition, the expression of several key proteins involved in the phosphatidylinositol‑4,5‑bisphosphate 3‑kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway was altered in M14 cells treated with UNBS5162. Based on these results, it may be hypothesized that UNBS5162 suppresses the proliferation of M14 cells by inducing apoptosis via inhibition of key proteins in the PI3K/Akt/mTOR signaling pathway.

Inhibition of PI3K/AKt/mTOR signaling pathway protects against d-galactosamine/lipopolysaccharide-induced acute liver failure by chaperone-mediated autophagy in rats

OBJECTIVE

This study aims to investigate the effects of PI3K/AKt/mTOR signaling pathway on the proliferation and apoptosis in acute liver failure (ALF) by chaperone mediated autophagy (CMA).

METHODS

The hepatocytes extracted from both normal rats and rats with ALF were assigned to control, acute injury, P13K agonist, and P13K inhibitor groups. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used as part of this investigation to detect the expression of PI3K/AKt/mTOR signaling pathway related-proteins (PI3K, AKt, mTOR), apoptosis related-proteins (Fas, Bax, Bcl-2), chaperone-mediated autophagy (CMA) marker proteins (LAMP-2A, HSC 70), p-PI3K, p-AKt, p-4E-BPI, and p-S6K. An MTT assay was used for analysis of cell proliferation after transfection. Flow cytometry is performed to detect the cell apoptosis.

RESULTS

In comparison to the normal group, the model group showed enhanced positive rate of PI3K, AKt, mTOR, increased expression levels of PI3K, AKt, mTOR, Fas, Bax, p-PI3K, p-AKt, p-4E-BPI and p-S6K, reduced expression levels of Bcl-2, LAMP-2A and HSC 70. The results in vitro experiment: compared with the acute injury group, the PI3K agonist group showed elevated expression levels of PI3K, AKt, mTOR, Fas, Bax, p-PI3K, p-AKt, p-4E-BPI and p-S6K, decreased expression levels of Bcl-2, LAMP-2A and HSC 70, inhibited cell proliferation, more arrested cells in G1 stage, and promoted cell apoptosis. Opposing this, the P13K inhibitor group exhibited an opposite trend.

CONCLUSION

In conclusion, inhibition of the PI3K/AKt/mTOR signaling pathway plays a protective role in ALF by promoting CMA expression, which could arrest cell proliferation and promote cell apoptosis.

Anti-proliferative, pro-apoptotic and anti-invasive effect of EC/EV system in human osteosarcoma

Osteosarcoma is the most common and aggressive bone tumor in children. The Endocannabinoid/Endovanilloid system has been proposed as anticancer target in tumor of different origins. This system is composed of two receptors (CB1 and CB2), the Transient Potential Vanilloid 1 (TRPV1) channel and their ligands and enzymes. CB1 is expressed mainly in central nervous system while CB2 predominantly on immune and peripheral cells. We investigated the effects of JWH-133 (CB2 agonist) and RTX (TRPV1 agonist) in six human Osteosarcoma cell lines: MG-63, U-2OS, MNNG/HOS, Saos-2, KHOS/NP, Hs888Lu, by Apoptosis and Migration-Assay. We also compared the effects of these compounds on Caspase-3, AKT, MMP-2 and Notch-1 regulation by Q-PCR and Western Blotting.

We observed an anti-proliferative, pro-apoptotic, anti-invasive effect. Our results show that both CB2 stimulation and TRPV1 activation, in different Osteosarcoma cell lines, can act on the same pathways to obtain the same effect, indicating the Endocannabinoid/Endovanilloid system as a new therapeutic target in Osteosarcoma.