ABSTRACT
Objective:To evaluate the inhibitory effect of a retinoid derivative ECPIRM on proliferation of a cutaneous T-cell lymphoma (CTCL) cell line HH, and to explore its potential mechanisms.Methods:Cultured HH cells were treated with ECPIRM at different concentrations of 0 (control group) , 5, 10 and 20 μmol/L separately for 72 hours, cell counting kit-8 (CCK8) assay was performed to evaluate the effect of ECPIRM on the proliferative activity of HH cells, and flow cytometry to investigate the effect of ECPIRM on apoptosis of HH cells. Some HH cells were treated with 10 μmol/L ECPIRM for 72 hours, transcriptome sequencing was performed to investigate gene expression changes triggered by ECPIRM in HH cells, and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis and gene ontology (GO) enrichment analysis were then performed to analyze differentially expressed genes in HH cells induced by ECPIRM. Reverse transcription-qPCR was subsequently conducted to verify changes in key gene expression in related pathways. Intergroup differences were analyzed by using one-way analysis of variance, and least significant difference (LSD) - t test was used for multiple comparisons. Results:CCK8 assay showed that the 50% inhibitory concentration (IC50) of ECPIRM on HH cells was 4.91 ± 2.48 μmol/L, the viability of HH cells significantly differed among the control group, and 5-, 10-and 20-μmol/L ECPIRM groups (100.00% ± 2.87%, 49.58% ± 4.53%, 48.36% ± 2.88%, 31.44% ± 2.46%, respectively, F=162.86, P < 0.001) , and was significantly lower in the 5-, 10-and 20-μmol/L ECPIRM groups than in the control group ( t=15.36, 15.73, 20.89, respectively, all P < 0.001) . Flow cytometry showed that there was a significant difference in the apoptosis rate among the 4 groups (11.51% ± 1.84%, 23.83% ± 5.72%, 36.19% ± 8.33%, 49.75% ± 4.10%, respectively, F=17.62, P < 0.001) , and the 10-and 20-μmol/L groups showed significantly increased apoptosis rates compared with the control group ( t=4.46, 6.92 respectively, both P < 0.01) . Transcriptomics analysis revealed that the inhibitory effect of ECPIRM on the cellular proliferative activity may be related to the metabolic regulation of steroids. As reverse transcription-qPCR revealed, the 10-μmol/L ECPIRM group showed significantly decreased mRNA expression of L-amino acid oxidase (IL4I1) , acetyl-coenzyme A acetyltransferase 2 (ACAT2) , 3-hydroxy-3-methylglutaryl-coenzyme A synthase 1 (HMGCS1) , mevalonate diphosphate decarboxylase (MVD) , 3-β-hydroxysteroid-8,7-isomerase (EBP) , very low-density lipoprotein receptor (VLDLR) , 3-hydroxy 3-methylglutaryl-CoA reductase (HMGCR) compared with the control group (all P < 0.05) . Conclusion:The retinoid derivative ECPIRM exerted marked anti-proliferative and apoptosis-inducing effects on HH cells, which may be related to the decreased expression of key genes involved in steroid metabolism.
ABSTRACT
Objective To evaluate the effect of chidamide combined with matrine on proliferation and apoptosis of cutaneous T-cell lymphoma (CTCL) cell lines HH and Hut78,and to explore their apoptotic mechanisms.Methods Both HH and Hut78 cells were treated with 0.4 μmol/L chidamide and 0.6 g/L matrine alone or in combination for 24,48 and 72 hours,with those treated with dimethyl sulfoxide (DMSO) serving as control groups.MTS assay was performed to deteet cellular proliferation rates of HH and Hut78 cells at each time point.After 48-hour treatment,flow cytometry was conducted to detect cell apoptosis,and Western blot analysis to determine expression of apoptosis-related proteins in these cells.Statistical analysis was carried out by using repeated measures analysis of variance,one-way analysis of variance,and least significant difference (LSD)-t test for multiple comparisons.Results Compared with DMSO,chidamide and matrine alone or in combination could inhibit the proliferation of HH and Hut78cells to different extents (F =15.88,558.26,P ＜ 0.05,＜ 0.001,respectively).At 48 hours,the apoptosis rate in Hut78 cells was significantly higher in the matrine group (20.98％ ± 1.53％),chidamide group (22.44％ ± 7.74％) and combination group (44.53％ ± 1.85％) than in the control group (8.42％ ± 4.23％;LSD-t =4.76,5.31,13.69 respectively,all P ＜ 0.05),as well as in the combination group than in the matrine group and chidamide group (LSD-t =8.93,8.37 respectively,both P ＜ 0.01);no significant differences were observed in the apoptosis rate of HH cells between the matrine group (13.98％ ± 3.86％)or chidamide group (13.61％ ± 1.62％) and control group (11.44％ ± 1.43％,both P ＞ 0.05),while the combination group (20.94％ ± 0.64％) showed a significantly higher apoptosis rate compared with the control group,matrine group and chidamide group (LSD-t =7.37,5.40,5.69 respectively,all P ＜ 0.05).In the case of HH cells,the combination group showed significantly higher cleaved caspase-3 expression (all P ＜ 0.05),but significantly lower protein expression of E-cadherin,nuclear factor (NF)-κB,phosphorylated-Bad (p-Bad) and Bcl-2 compared with the other 3 groups (all P ＜ 0.05).In the case of Hut78 cells,the expression of E-cadherin,NF-κB,p-Bad and Bcl-2 was significantly lower in the matrine group,chidamide group and combination group than in the control group (all P ＜ 0.05),while cleaved caspase-3 expression was significantly higher in the chidamide group and combination group than in the control group (both P ＜0.05).No matter in HH cells or in Hut78 cells,there were no significant differences in Bad protein expression between the 4 groups (all P ＞ 0.05).Conclusion Chidamide in combination with matrine can inhibit proliferation and induce apoptosis of HH and Hut78 cells,likely by regulating the expression of apoptosis-related proteins E-cadherin,NF-κB,p-Bad,Bcl-2 and cleaved caspase-3.