Bruceine A inhibited breast cancer proliferation and metastasis by inducing autophagy via targeting PI3K-AKT signaling pathway.

Although there have been significant advances in cancer treatment, the urgent need to inhibit breast cancer metastasis remained unmet. Bruceine A (BA) is a natural compound extracted from Bruceae Fructus and has long been recognized to have antitumor effects with high safety and biocompatibility. However, the mechanisms and/or targets of BA for metastatic breast cancer treatment are still not fully elucidated. In this study, we systematically investigated the effects of BA on inhibition of breast cancer metastasis and its underlying mechanisms. We found that, in addition to its cytotoxic effects, BA significantly inhibited the invasion and migration capabilities of two types of breast cancer cell lines (MDA-MB-231 and MCF-7) while concurrently promoting apoptosis in these cells. Further mechanistic studies revealed that, by targeting the canonical PI3K-AKT signaling pathway, BA initiated autophagy of both types of breast cancer cell lines in vitro. In vivo results further confirmed the in vitro findings, manifested by shrinkage of size and weight of breast tumor as well as initiation of autophagy (indicated by upregulation of LC3I/II) through targeting PI3K-AKT pathway on mice model. These data collectively demonstrated the potential of BA in antimetastasis of breast cancer cells, suggesting its future clinical transformation in metastatic breast cancer therapy.

Sphingosine 1-phosphate receptor 2 promotes the onset and progression of non-alcoholic fatty liver disease-related hepatocellular carcinoma through the PI3K/AKT/mTOR pathway.

PURPOSE: Recent studies have revealed an increase in the incidence rate of non-alcoholic fatty liver disease-related hepatocellular carcinoma (NAFLD-HCC). Furthermore, the association of Sphingosine 1-phosphate receptor 2 (S1PR2) with various types of tumours is identified, and the metabolism of conjugated bile acids (CBAs) performs an essential function in the onset and development of HCC. However, the association of CBA and S1PR2 with NAFLD-HCC is unclear. METHODS: The relationship between the expression of S1PR2 and the prognosis of patients suffering from NAFLD-HCC was investigated by bioinformatics techniques. Subsequently, the relationship between S1PR2 and the biological behaviours of HCC cell lines Huh 7 and HepG2 was explored by conducting molecular biology assays. Additionally, several in vivo animal experiments were carried out for the elucidation of the biological impacts of S1PR2 inhibitors on HCC cells. Finally, We used Glycodeoxycholic acid (GCDA) of CBA to explore the biological effects of CBA on HCC cell and its potential mechanism. RESULTS: High S1PR2 expression was linked to poor prognosis of the NAFLD-HCC patients. According to cellular assay results, S1PR2 expression could affect the proliferation, invasion, migration, and apoptosis of Huh 7 and HepG2 cells, and was closely associated with the G1/G2 phase of the cell cycle. The experiments conducted in the In vivo conditions revealed that the overexpression of S1PR2 accelerated the growth of subcutaneous tumours. In addition, JTE-013, an antagonist of S1PR2, effectively inhibited the migration and proliferation of HCC cells. Furthermore, the bioinformatics analysis highlighted a correlation between S1PR2 and the PI3K/AKT/mTOR pathway. GCDA administration further enhanced the expression levels of p-AKT, p-mTOR, VEGF, SGK1, and PKCα. Moreover, both the presence and absence of GCDA did not reveal any significant change in the levels of S1PR2, p-AKT, p-mTOR, VEGF, SGK1, and PKCα proteins under S1PR2 knockdown, indicating that CBA may regulates the PI3K/AKT/mTOR pathway by mediating S1PR2 expression. CONCLUSION: S1PR2 is a potential prognostic biomarker in NAFLD-HCC. In addition, We used GCDA in CBAs to treat HCC cell and found that the expression of S1PR2 was significantly increased, and the expression of PI3K/AKT/mTOR signalling pathway-related signal molecules was also significantly enhanced, indicating that GCDA may activate PI3K/AKT/mTOR signalling pathway by up-regulating the expression of S1PR2, and finally affect the activity of hepatocellular carcinoma cells. S1PR2 can be a candidate therapeutic target for NAFLD-HCC. Collectively, the findings of this research offer novel perspectives on the prevention and treatment of NAFLD-HCC.

PPARγ Mediates Protective Effect against Hepatic Ischemia/Reperfusion Injury via NF-κB Pathway.

BACKGROUND: Hepatic ischemia/reperfusion injury (HIRI) is an unavoidable complication in liver surgery, however its pathological process is still unclear. Therefore, in this study, the role and mechanism of peroxisome proliferator-activated receptor gamma (PPARγ) was investigated in HIRI. MATERIALS AND METHODS: We constructed mice models with HIRI and L02 cell models insulted hypoxia/re-oxygenation (H/R). PPARγ agonist rosiglitazone was administered prior to HIRI in mice and PPARγ-siRNA was to H/R treatment in L02 cells. Liver injury was measured by serum ALT, AST and LDH levels and performing H&E staining; the inflammatory injury was reflected by inflammatory markers IL-1ß, IL-6 and TNF-α, which were assayed by Real-time PCR and Western blotting, MPO activity was determined using commercial kits; oxidative stress injury was evaluated by iNOS, MDA, SOD and GSH-PX levels; apoptosis was detected by cleaved-Caspase-3, TUNEL staining and flow cytometry; NF-κB signaling activation was reflected by phosphorylation of IκBα (p-IκBα) and nuclear translocation of NF-κB p65. RESULTS: The level of PPARγ expression was obviously down-regulated both in mice liver subjected to IRI and in L02 cells to H/R. Overexpression of PPARγ presented protective effect on HIRI by reducing serum levels of aminotransferase and hepatic necrosis, inhibiting inflammation and apoptosis and alleviating oxidative stress in vivo. But PPARγ-siRNA aggravate H/R insult by promoting inflammation and apoptosis in vitro. Mechanistically, the NF-κB pathway activity was increased with PPARγ down-regulation by PPARγ-siRNA. Importantly, inhibition of NF-κB signaling abolished PPARγ knockdown-mediated hepatic injury. CONCLUSIONS: PPARγ present protective effects on HIRI by attenuating liver injury, inflammatory response, oxidative stress and apoptosis in vivo and in vitro, and its mechanism may be related to down-regulation of NF-κB signaling.

Hydrogen inhibits the proliferation and migration of gastric cancer cells by modulating lncRNA MALAT1/miR-124-3p/EZH2 axis.

BACKGROUND: Gastric cancer is one of the most prevalent and deadly malignancies without efficient treatment option. This study aimed to investigate the effect of hydrogen gas on the behavior of gastric cancer cells. METHODS: Gastric cancer cell lines MGC-803 and BGC-823 were treated with or without H2 /O2 gas mixture (66.7%:33.3% v/v). Proliferation and migration were assessed by MTT and scratch wound healing assays respectively. The expression of lncRNA MALAT1, miR-124-3p, and EZH2 was analyzed by real-time quantitative PCR and/or western blot. Tumor growth was estimated using xenograft mouse model. RESULTS: H2 gas significantly inhibited gastric tumor growth in vivo and the proliferation, migration, and lncRNA MALAT1 and EZH2 expression of gastric cancer cells while upregulated miR-124-3p expression. LncRNA MALAT1 overexpression abolished all the aforementioned effects of H2. LncRNA MALAT1 and miR-124-3p reciprocally inhibited the expression of each other. MiR-124-3p mimics abrogated lncRNA MALAT1 promoted EZH2 expression and gastric cancer cell proliferation and migration. CONCLUSIONS: These data demonstrated that H2 might be developed as a therapeutics of gastric cancer and lncRNA MALAT1/miR-124-3p/EZH2 axis could be a target for intervention.

Quantitative assessment of the influence of glutathione S-transferase T1 null variant on gastric cancer risk.

Glutathione S-transferase T1 (GSTT1) catalyzes reactions between glutathione and lipophilic compounds with electrophilic centers, leading to neutralization of toxic compounds, xenobiotics, and products of oxidative stress. In the past decade, a number of case-control studies have been carried out to investigate the relationship between the GSTT1 null polymorphism and gastric cancer (GC), but the results have been inconclusive. To investigate this inconsistency, we performed a meta-analysis of 46 studies involving a total of 9012 GC cases and 14,215 controls for null variant of the GSTT1 gene to evaluate the effect of GSTT1 on genetic susceptibility for GC. Potential sources of heterogeneity including ethnicity, source of control, and sample size were also assessed. Overall, significantly increased GC risk was associated with GSTT1 null polymorphism with OR of 1.20 (95% CI, 1.10-1.32; P < 0.05). In the subgroup analysis by ethnicity, significantly increased risks were found in East Asians and Indians, while no significant associations were found among Caucasian, and Middle Eastern and African populations. By pooling data from 19 studies that considered combinations of GSTT1 and GSTM1 genotypes, a statistically significant increased risk for GC (OR = 2.04, 95% CI, 1.49-2.64; P < 0.05) was detected for individuals with dual deletion in both genes compared with positive genotypes. In addition, we found that cigarette smoking and alcohol drinking may modified the association of GSTT1 null genotypes with the risk of GC. In conclusion, this meta-analysis suggests that GSTT1 null polymorphism is associated with elevated GC risk, but these associations vary in different ethnic populations.

Association between Bmi1 and clinicopathological status of esophageal squamous cell carcinoma.

AIM: To investigate the clinicopathological roles of Bmi1 in esophageal squamous cell carcinoma (ESCC). METHODS: Quantitative real-time polymerase chain reaction and immunohistochemical staining for Bmi1 were performed in cancerous and adjacent non-cancerous paraffin-embedded esophageal specimens. RESULTS: The Bmi1 expression level was unaffected by gender and age. The level of Bmi1 mRNA in ESCC was significantly higher than that in the adjacent non-cancerous tissues (2.181 +/- 2.158 vs 0.931 +/- 0.894, P = 0.0152), and its over-expression was aggressively associated with lymph node metastasis (3.580 +/- 2.487 vs 1.703 +/- 0.758, P = 0.0003), poorer cell differentiation (P = 0.0000) and advanced pathological stage (3.827 +/- 2.673 vs 1.590 +/- 0.735, P = 0.0001). The patients were divided into high-expression and low-expression groups based on the median expression level of Bmi1 mRNA, and a shorter overall survival time in the former group was observed. Immunohistochemistry for Bmi1 oncoprotein showed diffusely positive, focally positive and negative expression in 44, 16 and 10 of 70 ESCC cases, respectively, compared with three, two and five of 10 adjacent non-cancerous cases (P = 0.027). The positive rate of the oncoprotein in samples of histological grade III was higher than that of grade II (P = 0.031), but its expression had no relation to the lymph node metastasis and pathological staging. In 70 ESCC samples, Bmi1 showed high intense expression in the cytoplasm and less or even no expression in the nucleus. CONCLUSION: Bmi1 was over-expressed in ESCC. Increased Bmi1 mRNA expression was significantly associated with ESCC progression, and the oncoprotein was largely distributed in the cytoplasm of tumor cells.