Overexpression of ZIC1 results in inactivation of Shh, PI(3)K and MAPK signaling pathways, as well as regulation of multiple downstream targets which are essential for the development and progression of gastric cancer.
The expression of phosphatidylinositol 3' -kinase (PI3K)/ protein kinase B (AKT) and c-Jun N-terminal kinase (JNK) was down-regulated by GEN (all P < .05) while reversed by HULC overexpression.HULC was up-regulated in GC.
PIK3R3, the gene that encodes the PI3K regulatory subunit p55γ, is over-expressed in glioblastoma and ovarian cancers, but its expression in gastric cancer (GC) is not known.
The experimental methods are as follows: (1) The proliferation of HGC-27 cells inhibited by Apatinib and LY294002 was observed by 3-(4,5)-dimethylthiahiazo-(z-y1)-3,5-diphenytetrazoli- umromide (MTT) assay; (2) flow cytometry was adopted to detect the apoptosis of cells after they were treated with drugs and the positive control; (3) different effects of varying concentrations of Apatinib on apoptosis-related genes and proteins, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax) and cysteine-aspartic acid protease (Caspase) 9, were detected via fluorescence quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting (WB), and the effects of different concentrations of Apatinib on the protein expressions of PI3K, phosphorylated (p)-PI3K, Akt and p-Akt were detected by Western blotting.
The effects of miR-34a ectopic expression on the AKT and p-AKT expression of cisplatin-induce gastric cancer cells were determined by Western blot and flow cytometry with the PI3K pathway inhibitor Wortmannin.
This study demonstrates, for the first time, that SHIP2 is frequently downregulated in gastric cancer, and reduced SHIP2 expression promotes tumorigenesis and proliferation of gastric cancer via activation of the PI3K/Akt signaling.
Moreover, research on molecular mechanisms indicated that both miRNA-32-5p and shKLF2 downregulated the expression of PTEN and activated the PI3K/AKT signaling to promote the development of gastric cancer.
Our study aimed to explore the effects of PPIs on reversing multidrug resistance (MDR) to chemotherapy in gastric cancer by inhibiting the expression of V-ATPases and the PI3K/Akt/mTOR/HIF-1α signal pathway.
These results show that H. pylori infection induces AKT/PI3K-mediated phosphorylation of p27 at T157 and T198 to cause cytoplasmic p27 mislocalization in gastric cancer, and that p27 mislocalization is an adverse prognostic feature in gastric cancer.
AdP promoted apoptosis in CDDP-resistant GC cells by suppressing the PI3K/AKT/ARNT signaling pathway and might be considered a candidate agent for the clinical treatment of cisplatin-resistant GC.