Mouse CDK4 blocking peptide

OBJECTIVE: This study aims to investigate the expression characteristics of Kruppel-like factor 5 (KLF5) in gastric cancer (GC) and its potential correlation to pathological indexes in GC patients. Molecular mechanisms underlying the regulatory effect of KLF5 on GC progression are explored. PATIENTS AND METHODS: KLF5 expressions in GC tissues were analyzed through GE-PIA dataset and those collected in our hospital. By analyzing the clinical data of GC patients, the correlation between KLF5 level and pathological characteristics of GC was determined. The regulatory effects of KLF5 on proliferative ability and cell cycle progression of SGC7901 and MGC803 cells were assessed by Cell Counting Kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU) assay, and flow cytometry. The regulation of KLF5 on expression levels of p21 and CDK4 in GC cells was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot. RESULTS: KLF5 was markedly upregulated in GC tissues. KLF5 level was positively correlated to TNM staging, tumor size, and metastasis of GC. Meanwhile, high level of KLF5 predicted poor prognosis in GC patients. The knockdown of KLF5 in SGC7901 and MGC803 cells attenuated proliferative ability and arrested cell cycle in G0/G1 phase. Both mRNA and the protein levels of p21 were upregulated, and CDK4 levels were downregulated in SGC7901 and MGC803 cells transfected with si-KLF5. CONCLUSIONS: KLF5 is upregulated in GC and closely linked to pathological characteristics of GC patients. High level of KLF5 indicates poor prognosis of GC. It is believed that KLF5 may be a potential therapeutic target for GC.

Background Granulosa cells (GCs) proliferation and estradiol synthesis significantly affect follicular development. The miR-214-3p expression in the ovarian tissues of high-yielding sows is higher than that in low-yielding sows, indicating that miR-214-3p may be involved in sow fertility. However, the functions and mechanisms of miR-214-3p on GCs are unclear. This study focuses on miR-214-3p in terms of the effects on GCs proliferation and estradiol synthesis. Results Our findings revealed that miR-214-3p promotes proliferation and inhibits estradiol synthesis in porcine GCs. MiR-214-3p can increase the percentage of S-phase cells, the number of EdU labeled positive cells, and cell viability. However, E(2)concentration was reduced after miR-214-3p agomir treatment. We also found that miR-214-3p up-regulates the expression of cell cycle genes including cell cycle protein B (Cyclin B), cell cycle protein D (Cyclin D), cell cycle protein E (Cyclin E), and cyclin-dependent kinase 4 (CDK4) at the transcription and translation levels, but down-regulates the mRNA and protein levels of cytochrome P450 family 11 subfamily A member 1 (CYP11A1), cytochrome P450 family 19 subfamily A member 1 (CYP19A1), and steroidogenic acute regulatory protein (StAR) (i.e., the key enzymes in estradiol synthesis). On-line prediction, bioinformatics analysis, a luciferase reporter assay, RT-qPCR, and Western blot results showed that the target genes of miR-214-3p in proliferation and estradiol synthesis areMfn2andNR5A1, respectively. Conclusions Our findings suggest that miR-214-3p plays an important role in the functional regulation of porcine GCs and therefore may be a target gene for regulating follicular development.