Investigating the protective effects of Astragalus polysaccharides on cyclophosphamide-induced bone marrow suppression in mice and bone mesenchymal stem cells.

BACKGROUND: This study determines the role and mechanism of APS in cyclophosphamide-induced myelosuppression in mice and bone mesenchymal stem cells (BMSCs) cell model. METHODS: Cy-induced myelosuppression mice and BMSCs cell model were established. Fifty C57BL/6 mice (weighing 20 ± 2 g) were randomly divided into five groups. Femur and tibia samples, bone marrow samples, and blood samples were collected 3 days after the last injection of Cy. Histopathology changes and cell apoptosis were detected. Cell viability, apoptosis, cycle distribution, reactive oxygen species activity, osteogenesis ability, and protein levels were detected. γ-H2AX and senescence-associated ß-galactosidase activity expression was detected by immunofluorescence. Cy-induced senescence and Wnt/ß-catenin related protein levels were detected using western blotting. RESULTS: The results showed that APS effectively induced Cy-induced histological injury and cell apoptosis rate. After treated with APS, ROS and ALP levels were significantly increased. In BMSCs, cell viability, apoptosis, and cell cycle distribution were also influenced by APS treatment. Compared with the control group, cell viability was significantly increased, the cell apoptosis rate was decreased while the number of cells remained in the G0-G1 phase was increased. Meanwhile, ROS levels were significantly increased in APS group. Cell senescence and Wnt/ß-catenin related protein (γ-H2AX, SA-ß-gal, p21, p16, p-ß-catenin/ ß-catenin, c-Myc, and AXIN2) levels were also altered both in vivo and in vitro. Interestingly, the effects of APS were reversed by BML-284. CONCLUSION: Our results indicate that APS protected Cy-induced myelosuppression through the Wnt/ß-catenin pathway and APS is a potential therapeutic drug for Cy-induced myelosuppression.

Kanglaite reverses multidrug resistance of HCC by inducing apoptosis and cell cycle arrest via PI3K/AKT pathway.

BACKGROUND: Multidrug resistance (MDR) frequently contributes to the failure of chemotherapeutic treatments in patients diagnosed with hepatocellular carcinoma (HCC). Revealing the molecular mechanism of MDR is indispensable for the development of effective chemotherapeutic drugs. PURPOSE: Due to the low-toxicity modulators to inhibit MDR, we considered that Kanglaite (KLT) is a potential agent for reversing MDR in HCC. MATERIALS AND METHODS: BEL-7402/5-fluorouracil (5-FU) and HepG2/adriamycin (ADM) were analyzed for cell viability, colony formation assay, cell scratch assay, and cell cycle analysis and apoptosis assay by flow cytometry. The expression of PARP, caspase-3, Bax, Bcl-2, CDC25C, Cyclin B1 and phosphorylation of PTEN, PI3K, and AKT in HepG2/ADM cells were detected by western blotting. RESULTS: The proliferation of drug-resistant cell lines BEL-7402/5-FU and HepG2/ADM pretreated with KLT was significantly inhibited when compared with drug alone. KLT could increase the accumulation of ADM in HepG2/ADM cells. In this study, we found that KLT treatment notably reduced cell viability, induced apoptosis and cell cycle arrest in human HepG2/ADM and BEL-7402/5-FU cells, and effectively reversed the MDR by p-glycoprotein (P-gp) inhibition. Moreover, KLT decreased the phosphorylation of AKT and PI3K in KLT-treated HepG2/ADM cells. These data together implied that KLT might reverse drug resistance in HCC by blocking the PI3K/AKT signaling. CONCLUSION: We demonstrated that KLT reversed MDR of human HCC by inducing apoptosis and cell cycle arrest via the PI3K/AKT signaling pathway.

MiR-34a Inhibits Breast Cancer Proliferation and Progression by Targeting Wnt1 in Wnt/ß-Catenin Signaling Pathway.

BACKGROUND: As microRNA-34a (miR-34a) has been suggested to be associated with breast cancer (BC), this study was proposed to explore the underlying mechanism of miR-34a in suppressing BC progression. METHODS: A total of 123 pairs of tumor tissues and matched nontumor tissues were obtained from patients. Reverse transcription polymerase chain reaction and in situ hybridization were used to detect the differences in miR-34a expression in tissues and cells. Whether Wnt1 is a direct downstream target of miR-34a was confirmed by both bioinformatics target gene prediction and dual-luciferase report assay. Wnt1 and other gene expressions that are related to Wnt/ß-catenin signaling pathway were assessed by reverse transcription polymerase chain reaction and western blot when MCF-7A cells were transfected with miR-34a mimic or miR-34a inhibitor. The proliferation, invasion and migration status of MCF-7 cells after transfection were assessed by MTT assay, wound healing assay and transwell assays, respectively. Breast tumor xenograft models on mice were also constructed to determine the effect of miR-34a on breast tumor growth in vivo. RESULTS: MiR-34a expression was remarkably down-regulated in BC tissues and cell lines compared with normal tissues and cell lines. Wnt1 was a direct downstream target of miR-34a and low expression of miR-34a contributed to the Wnt/ß-catenin signaling pathway activation in MCF-7A cells. MiR-34a inhibited the proliferation, invasion and migration of BC in vitro and breast tumor growth in vivo through deactivating the Wnt/ß-catenin signaling pathway. CONCLUSION: MiR-34a may suppress the proliferation and progression of BC via mediating the Wnt/ß-catenin signaling pathway.