H-Index
79
Scimago Lab
powered by Scopus
JCR
Clarivate
Analytics
16%
Acceptance
Rate
call: +1.631.470.9640
Mon-Fri 10 am - 2 pm EST

Logo



eISSN: 1643-3750

Get your full text copy in PDF

Regenerating Family Member 4 (Reg4) Enhances 5-Fluorouracil Resistance of Gastric Cancer Through Activating MAPK/Erk/Bim Signaling Pathway

Jiaoyue Jin, Hang Lv, Junzhou Wu, Dan Li, Kaiyan Chen, Fanrong Zhang, Jing Han, Jianguo Feng, Nan Zhang, Herbert Yu, Dan Su, Lisha Ying

(Cancer Research Institute, Zhejiang Cancer Hospital and Key Laboratory Diagnosis and Treatment Technology on Thoracic Oncology of Zhejiang Province, Hangzhou, Zhejiang, China (mainland))

Med Sci Monit 2017; 23:3715-3721

DOI: 10.12659/MSM.903134


BACKGROUND: Reg4, a member of the Reg multigene family, is highly upregulated in many gastrointestinal cancers including gastric cancer (GC). The enhanced expression of Reg4 is associated with the resistance of GC to 5-fluorouracil (5-FU), while the underlying mechanism is not clear. The aim of the present study was to explore the resistant mechanism underlying 5-FU resistance.
MATERIAL AND METHODS: Reg4 expression was assessed by Western blot analysis for SGC-7901, BGC-823, AGS, MKN28, and MKN45. Synthetic short single strand RNA oligonucleotides and Flag-Reg4 plasmid were used to investigate the biological function of Reg4 in vitro. The cell viability assay was performed by MTT. Flow cytometry was carried out to measure the apoptosis caused by 5-FU. Reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR) was used to examine the expression of 5-FU metabolism related enzymes. The effect of Reg4 on intracellular signaling was evaluated by Western blot.
RESULTS: Western blot analysis of 5 GC cells showed that Reg4 was low or null in SGC-7901 and BGC-823, while high in AGS, MKN28, and MKN45. Over-expression of flag-Reg4 in SGC-7901 led to an increase in cell viability and lower apoptosis with 5-FU treatment. In contrast, siRNA knockdown of Reg4 enhanced 5-FU induced apoptosis. However, over-expression or knockdown of Reg4 had no significant influence on the expression of 5-FU metabolic enzymes. Further investigation revealed that Reg4 could activate Erk1/2-Bim-caspase3 cascade.
CONCLUSIONS: Reg4 inhibited apoptosis through regulating MAPK/Erk/Bim signaling pathway and thereby enhanced the resistance of GC to 5-FU.

This paper has been published under Creative Common Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) allowing to download articles and share them with others as long as they credit the authors and the publisher, but without permission to change them in any way or use them commercially.
I agree