Proteomics reveals protein profile changes in cyclooxygenase-2 inhibitor-treated endometrial cancer cells
Zhang Yi1, Cai Jingting, Zhang Yu
1Department of Obstetrics and Gynecology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China.
Objective:
To examine effects of an inhibitor of cyclooxygenase (COX)-2, NS-398, on the proliferation, apoptosis and invasion characteristics of endometrial cancer cell RL95-2.
Methods:
(1) Western blotting was carried out to determine COX-2 protein expression in RL95-2 cells and normal endometrium specimens. (2) The effect of NS-398 treatment on the cell proliferation, apoptosis, and invasion was assessed by methyl thiazolyl tetrazolium assay, flow cytometry, and matrigel invasion assay, respectively. (3) Finally, the proteomic analysis was used to find out proteins that are differentially expressed because of NS-398 treatment.
Results:
(1) COX-2 protein in RL95-2 cell line was significantly higher than that in normal endometrium. (2) NS-398 had significant growth inhibition effects on RL95-2 cells in a dose- and time-dependent manner. (3) NS-398 increased the proportion of cells in G1 and decreased the proportion of cells in the G2 phase in RL95-2 cells. (4) NS-398 could restrain endometrial cancer cells invasion. (5) The proteomic analysis revealed several proteins that are differentially expressed because of NS-398 treatment; the down-regulated proteins identified are hnRNP K, alpha enolase, Hsp70, tropomyosin, and protein disulfide isomerase, the up-regulated protein is phosphatidylethanolamine binding protein.
Conclusions:
The expression of COX-2 plays an important role in tumorigenesis of endometrial cancer. NS-398 can inhibit the ability of RL95-2 cell proliferation, viability, and invasion. In this study, the well-resolved reproducible 2-DE maps of NS-398 treated and control RL95-2 cells were established, and the significantly different expressed proteins are preliminary identified.
Insights
Cyclooxygenase-2 (COX-2) is crucial in endometrial cancer. The COX-2 inhibitor NS-398 effectively reduced RL95-2 cell proliferation and invasion, offering potential therapeutic strategies.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- Cyclooxygenase-2 (COX-2) is implicated in endometrial cancer tumorigenesis.
- Elevated COX-2 protein expression was observed in RL95-2 endometrial cancer cells compared to normal endometrium.
Purpose of the Study:
- To investigate the effects of the COX-2 inhibitor NS-398 on endometrial cancer cell line RL95-2.
- To analyze the impact of NS-398 on cell proliferation, apoptosis, and invasion.
Main Methods:
- Western blotting to assess COX-2 protein levels.
- Methyl thiazolyl tetrazolium assay, flow cytometry, and matrigel invasion assay to evaluate cell proliferation, apoptosis, and invasion.
- Proteomic analysis (2-DE) to identify differentially expressed proteins following NS-398 treatment.
Main Results:
- NS-398 demonstrated dose- and time-dependent inhibition of RL95-2 cell proliferation.
- NS-398 treatment led to cell cycle arrest in the G1 phase and reduced G2 phase proportion.
- NS-398 significantly inhibited the invasion capabilities of endometrial cancer cells.
- Proteomic analysis identified several differentially expressed proteins, including down-regulation of hnRNP K, alpha enolase, Hsp70, tropomyosin, and protein disulfide isomerase, and up-regulation of phosphatidylethanolamine binding protein.
Conclusions:
- COX-2 expression is vital for endometrial cancer development.
- NS-398 effectively suppresses proliferation, viability, and invasion of RL95-2 cells.
- Proteomic analysis provided insights into the molecular mechanisms underlying NS-398's effects.
