Dihydropyrano[2,3-c]pyrazole-induced apoptosis in lung cancer cells is associated with ROS generation and activation of p38/JNK pathway

Miao He,Guangquan Yang,Zhaohong Chen,Chao Li,Yingying He,Youcai Zhang

doi:10.4314/tjpr.v19i10.5

Abstract

Purpose: To investigate the effect of 2,4-dihydropyrano[2,3-c]pyrazole (DHPP) on lung cancer cells, and the associated mechanism.Methods: The effect of DHPP on cell proliferation was measured using sulphorhodamine B (SRB) assay. Apoptosis of cells was determined using Olympus IX71 inverted microscope connected to FITC and rhodamine filters.Results: DHPP significantly suppressed the proliferation of A549 and H1299 cells at doses of 0.5-8.0 μM, but did not affect normal cells (MRC5 and BEAS-2B). In DHPP-treated A549 and H1299 cells, caspase-3 activity was markedly enhanced. At 24 h of treatment with 8.0 μM DUPP, apoptosis in A549 and H1299 cells was increased to 67.89 and 61.35 %, respectively. Phosphorylation levels of JNK-1/2 and p38 in DHPP-treated A549 and H1299 cells were markedly enhanced. The p-ERK-1/2 expressions in DHPP-treated A549 and H1299 cells were suppressed significantly at 24 h. In DHPP-treated A549 and H1299 cells, DCF-fluorescence was increased 10 folds and 8.5 folds, respectively. Pretreatment with FeTMPyP, an antioxidant, effectively alleviated DHPP-induced increase in expressions of p-p38 and p-JNK, and suppression of expression of p-ERK-1/2. In FeTMPyP-pre-treated cells, the DHPPinduced increase in caspase-3 activity was markedly reduced.Conclusion: DHPP selectively inhibits lung cancer cell growth via oxidative stress which subsequently causes cell apoptosis. Moreover, it activates caspase-3 protein and p38/JNK signaling, with simultaneous inactivation of ERK-1/2. Therefore, DHPP has a potential to be developed for the treatment of lung cancer. However; more studies are required to confirm these findings. Keywords: Lung cancer, Anti-oxidant, Apoptosis, Caspase-3, Chemotherapy

Highlights

Lung cancer is the most common cause of mortality associated with cancers, and it has very high metastatic potential [1]
Treatment with 8.0 μM DHPP decreased the viabilities of A549 and H1299 cell lines to 23 and 29 %, respectively
The present study demonstrated that DHPP exhibits anti-proliferative effect on A549 and H1299 lung cancer cells without affecting the growth of MRC5 and BEAS-2B

Summary

INTRODUCTION

Lung cancer is the most common cause of mortality associated with cancers, and it has very high metastatic potential [1]. Causative molecular mechanistic studies have very effectively helped in development of treatment strategies for lung cancer, as well as improvements in patient prognosis [2]. Heterocyclic molecules bearing pyrazole rings connected to pyrans possess diverse pharmacological properties Compounds such as 1,4- and 2,4dihydropyrano[2,3c]pyrazoles exhibit significant anticancer [10] and anti-inflammatory effects [11]. Protein probing was made by incubation overnight at 4 oC with primary antibodies against p-ERK-1/2, p-p38, p-JNK, α-tubulin, ERK-1/2, p38 and JNK (Cell Signaling Technology) This was followed by washing and 1 h incubation with anti-rabbit Ig-G-conjugated secondary antibody (Sigma-Aldrich) at room temperature. The effect of 24 h treatment with DHPP on caspase-3 activities in A549 and H1299 cells is shown in Figure 3 A. Differences were taken as significant at p < 0.05

RESULTS

DISCUSSION

CONCLUSION

Conflict of interest