Upregulation of CDK7 in gastric cancer cell promotes tumor cell proliferation and predicts poor prognosis

Background:Regenerating islet-derived gene family member 4 (Reg4), a well-investigated growth factor in the regenerative pancreas, has recently been reported to be highly associated with a majority of gastrointestinal cancers. Pathological hyper-expression or artificial over-expression of Reg4 causes acceleration of tumor growth, migration, and resistance to chemotherapeutic 5-Fluorouracil (5-FU). Until now, no method has been successfully established for eliminating the effects of Reg4 protein.Methods:This study reports the production of an engineered immunoglobin, a single-chain variable fragment (scFv-Reg4), to specifically bind Reg4 and block the bioactivity. The complementary-determining regions (CDRs) against Reg4 were assigned using MOE and ZDOCK servers. The binding affinity (KD) was determined by bio-layer interferometry (BLI). MKN45 and AGS cell proliferation was determined by Thiazolyl blue tetrazolium bromide (MTT) method and the cell apoptosis was detected by flow cytometry assay.Results:The KD of scFv-Reg4 to Reg4 was determined to be 1.91×10-8. In MKN45 and AGS cell lines, scFv- Reg4 depressed Reg4-stimulated cell proliferation and the inhibitory rates were 27.7±1.5% and 17.3±2.6%, respectively. Furthermore, scFv significantly enhanced 5-FU-induced cell death, from 23.0±1.0% to 28.4±1.2% in MKN45 and 28.2±0.7% to 36.6±0.6% in AGS cells. Treatment with scFv alone could lyse cancer cells to a certain extent, but no significance has been observed.Conclusion:The single-chain antibody (scFv-Reg4) significantly inhibited gastric cancer cell proliferation and synergistically enhanced the lethal effect of 5-FU. Thus, traditional chemo-/radio- therapeutics supplemented with scFv-Reg4 may provide advances in the strategy for gastrointestinal cancer treatment.

Download Full-text

Carnosic Acid Induces Apoptosis and Inhibits Akt/mTOR Signaling in Human Gastric Cancer Cell Lines

Pharmaceuticals ◽

10.3390/ph14030230 ◽

2021 ◽

Vol 14 (3) ◽

pp. 230

Author(s):

Waseem El-Huneidi ◽

Khuloud Bajbouj ◽

Jibran Sualeh Muhammad ◽

Arya Vinod ◽

Jasmin Shafarin ◽

...

Keyword(s):

Gastric Cancer ◽

Cell Proliferation ◽

Cancer Cell ◽

Gastric Cancer Cell ◽

Carnosic Acid ◽

Human Gastric Cancer ◽

Cancer Cell Proliferation ◽

Human Gastric Cancer Cell ◽

Gastric Cancer Cell Lines ◽

Gastric Cancer Cell Proliferation

Gastric cancer is among the most common malignancies worldwide. Due to limited availability of therapeutic options, there is a constant need to find new therapies that could target advanced, recurrent, and metastatic gastric cancer. Carnosic acid is a naturally occurring polyphenolic abietane diterpene derived from Rosmarinus officinalis and reported to have numerous pharmacological effects. In this study, the cytotoxicity assay, Annexin V-FITC/PI, caspases 3, 8, and 9, cell cycle analysis, and Western blotting were used to assess the effect of carnosic acid on the growth and survival of human gastric cancer cell lines (AGS and MKN-45). Our findings showed that carnosic acid inhibited human gastric cancer cell proliferation and survival in a dose-dependent manner. Additionally, carnosic acid is found to inhibit the phosphorylation/activation of Akt and mTOR. Moreover, carnosic acid enhanced the cleavage of PARP and downregulated survivin expression, both being known markers of apoptosis. In conclusion, carnosic acid exhibits antitumor activity against human gastric cancer cells via modulating the Akt-mTOR signaling pathway that plays a crucial role in gastric cancer cell proliferation and survival.

Download Full-text