ABSTRACT
In recent years, the clinical treatment of colorectal cancer(CRC) has made great progress, but chemoresistance is still one of the main reasons for reducing the survival rate of patients with colorectal cancer. Therefore, ameliorating chemotherapy resis-tance is an urgent problem to be solved. The purpose of this study was to investigate the regulatory role and related molecular mechanisms of hydroxysafflor yellow A(HSYA) in colorectal cancer cell proliferation, migration, and 5-fluorouracil(5-FU) chemoresistance. In this study, HCT116 and HT-29 cells were used as research subjects. Firstly, methyl thiazolyl tetrazolium(MTT) assay and colony formation assay were used to detect and analyze the effect of HSYA on the proliferation of CRC cells. Secondly, the effect of HSYA on the cell cycle in CRC cells was analyzed by cell cycle assay. Furthermore, the effect of HSYA on the migration of CRC cells was analyzed by wound-healing assay and Transwell assay. Based on the above, the influences of HSYA on 5-FU chemoresistance of CRC cells and related molecular mechanisms were explored and analyzed. The results showed that HSYA significantly inhibited the proliferation and migration of CRC cells, and arrested the cell cycle in G_0/G_1 phase. In addition, HSYA significantly ameliorated the chemoresistance of CRC cells to 5-FU. The results of acridine orange staining and Western blot showed that the autophagy activity of CRC cells in the HSYA and 5-FU combined treatment group was significantly higher than that in the 5-FU single drug treatment group. As compared with the 5-FU single drug treatment group, the phosphorylation levels of protein kinase B(Akt) and mammalian target of rapamycin(mTOR) in the HSYA and 5-FU combined treatment group were significantly reduced, indicating that the Akt/mTOR signaling pathway in the combined treatment group was down-regulated in CRC cells. In conclusion, HSYA may upregulate autophagy activity through the Akt/mTOR signaling pathway, thereby inhibiting the proliferation and migration of CRC cells and ameliorating the chemoresistance to 5-FU.
Subject(s)
Humans , Proto-Oncogene Proteins c-akt/metabolism , Drug Resistance, Neoplasm , Cell Line, Tumor , TOR Serine-Threonine Kinases/metabolism , Fluorouracil/pharmacology , Cell Proliferation , Autophagy , Colorectal Neoplasms/drug therapyABSTRACT
Objective To evaluate a new method for the isolation of rat pancreatic stellate cells (PSCs) and to investigate the influence of adipose derived stem cells (ADSCs) on PSCs in vitro.Methods Normal rat PSCs was isolated by collagenase and Optiprep density gradient centrifugation.The coculture system of ADSCs and PSCs was set up by transwell insert.The proliferation of PSCs was tested by CCK-8 test kit.Smoothmuscle α-actin (α-SMA) expression of PSCs were tested by Western blot.The apoptosis of HSCs was tested by flow cytometer.The cytokines in the culture solution were tested by ELISA kit.Results The quantity of PSCs was above 5 × 106 cells per rat.The purity and the viability of the cells were about 90-97 percent.After coculture for 72 h,the proliferation and activation of PSCs was inhibited by ADSCs (F =223.27,P ＜ 0.05 ; F =52.97,P ＜ 0.05) and the apoptosis of PSCs was promoted by ADSCs (F =43.62,P ＜ 0.05).more NGF and less TGF-β1 was secreted by ADSCs than by PSCs (NGF:14.68 ± 0.94 vs.8.31 ±0.86,t =4.67,P ＜0.05;TGF-β1:10.65 ±0.46 vs.70.47 ±0.99,t =21.72,P＜0.01).Conclusions ADSCs inhibit the proliferation and activation of PSCs by ADSCs secreting cytokines.
ABSTRACT
Objective To compare the difference between bone marrow stomal cell (BMSC) and adipose-derived stem cell (ADSC) of liver fibrosis in rats.Methods BMSC and ADSC of Sprague-Dawley (SD) rats were isolated and purified.The stem cell markers were detected with flow cytometry.The coculture system was set up with 0.4 μm Transwell insert semipermeable membrane.ADSC or BMSC were co-cultured with hepatic stellate cells (HSC).Normal hepatocyte cell line of rat (BRL) was co-cultured with HSC as negative control group and HSC cultured alone was blank control group.After cultured for 72 hours,the proliferation of HSC was determined by cell counting kit-8 (CCK-8) method.The expression of α-smooth muscle actin (α-SMA) of HSC was detected by Western blotting.The apoptosis of HSC was examined by flow cytometry.After BMSC,ADSC and BRL cultured alone for 72 hours,expression level vascular endothelial growth factor (VEGF),interleukin-10 (IL-10),nerve growth factor (NGF) and transforming growth factor-β1 (TGF-β1) in the culture medium were detected by enzymelinked immunosorbent assay (ELISA) method.The rats model of liver fibrosis were established.The rats were divided into BMSC treatment group,ADSC treatment group,BRL group and culture medium group,six rats in each group,which were injected with 1.5 mL BMSC,ADSC and BRL cells suspension (5 × 106) through portal vein,respectively,and same volume of culture medium was injected to the rate of culture medium group,once every two weeks for four weeks.The pathological changes of liver tissue sections were observed and liver fibrosis markers were tested.T test was performed for comparison between two samples and analysis of variance was used for comparison among multiple groups.Results BMSC and ADSC were successfully isolated and cultured.The phenotype of BMSC and ADSC was similar.Compared with blank control group and negative control group,both ADSC and BMSC could inhibit the proliferation of HSC and promote apoptosis (proliferation,2.43±0.27,2.39±0.33,1.92±0.38 and 2.18±0.31,FBMSC =25.61,FADSC =38.63,both P＜0.05 ;apoptosis rate,(5.59 ± 0.40)％,(6.82±0.57)％,(8.31± 1.03) ％ and (9.36 ± 0.54) ％,FBMSC =73.69,FADSC =97.41,both P＜ 0.05).The effects of ADSC were more significant than those of BMSC (t=5.76 and 5.18,both P＜0.05).There was difference in the cytokine levels secreted by ADSC and BMSC (NGF,(7.46 ± 0.54) pg/mL vs (3.95 ± 0.71) pg/mL,t =10.92,P＜0.05; TGF-β1,(8.79 ±0.93) pg/mL vs (6.36±0.85) pg/mL,t=7.58,P＜0.05).The cell transplantation experiment indicated that both BMSC and ADSC had significant inhibitory effect on liver fibrosis.The activity index of inflammation and degree of fibrosis in BMSC treatment group and ADSCs treatment group were 9.87±2.07,4.17 ± 0.94 and 10.13 ± 1.81,3.98 ± 0.82,which were significantly lower than those in blank control group (13.78±2.53 and 5.09±1.15)and negative control group (13.34± 1.89 and 4.95± 1.22,FBMSC=51.26 and 32.29,P＜0.05; FADSC =46.73 and 40.94,P＜0.05).The level of hyaluronic acid ((191.5±33.2) μg/L and (178.8±28.2) μg/L),type Ⅲ collagen ((19.9±5.1) μg/L and (21.7± 3.3) μg/L) and hydroxyproline ((312.6±38.8) μg/g and (325.8±28.2) μg/g) of BMSC treatment group and ADSC treatment group were significantly lower than those of negative control group and blank control group (hyaluronic acid,(282.3 ± 18.7) μg/L and (287.5 ± 26.7) μg/L),F =73.51 ; type Ⅲ collagen,(35.3± 3.3) μg/L and (32.5±4.3) μg/L,F=76.19; hydroxyproline,(458.4 ± 38.1) μg/g and (473.9 ± 63.7) μg/g,F=60.37,all P＜0.05).However,there was no difference between BMSC treatment group and ADSC treatment (all P＜0.05).Conclusions ADSC and BMSC had similar stem cell characteristics.There was difference in inhibiting the activation of HSC between ADSC and BMSC.But there was no significant difference in inhibiting liver fibrosis of rats in vivo.
ABSTRACT
<p><b>BACKGROUND</b>Candida albicans is the most frequently seen opportunistic human fungal pathogen. Terbinafine is an allylamine antifungal agent that has been proven to have high clinical efficacy in the therapy of fungal infections, the mechanism of action of terbinafine involves the specific inhibition of fungal squalene epoxidase, resulting in ergosterol deficiency and accumulation of intracellular squalene. We used cDNA microarray analysis technology to monitor global expression profile changes of Candida albicans genes in response to terbinafine treatment, and we anticipated a panoramic view of the responses of Candida albicans cells to the representatives of allylamine antifungal agents at the molecular level in an effort to identify drug class-specific and mechanism-independent changes in gene expression.</p><p><b>METHODS</b>Candida albicans strain ATCC 90028 was exposed to either medium alone or terbinafine at a concentration equivalent to the 1/2 minimal inhibitory concentrations (MICs, 4 mg/L) for 90 minutes. RNA was isolated and gene expression profiles were compared to identify the changes in the gene expression profile using a cDNA microarray analysis. Differential expression of 10 select genes detected by cDNA microarray analysis was confirmed by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>A total of 222 genes were found to be responsive to terbinafine, including 121 up-regulated genes and 101 down-regulated genes. These included genes encoding membrane transport proteins belonging to the members of the ATP-binding cassette (ABC) or major facilitator superfamily (MFS; CDR1, AGP2, GAP6, PHO84, HOL3, FCY23, VCX1), genes involved in stress response and detoxification (CDR1, AGP2, HOL3), and gene involved in the ergosterol biosynthesis pathway (ERG12). The results of semi-quantitative RT-PCR were consistent with that of the cDNA microarray analysis.</p><p><b>CONCLUSIONS</b>The up-regulation of the gene encoding the multidrug resistance efflux pump CDR1 may contribute to the terbinafine resistance in Candida albicans. However, the precise roles of other affected genes remain unclear, further studies of these genes and their respective products that play roles in the context of antifungal resistance are warranted.</p>