ABSTRACT: To detect the changes of heat shock protein(HSP) expression in human hepatocellular carcinoma HepG2 cells after treated by quercetin through a proteomics strategy termed SILAC (stable isotope labeling by amino acids in cell culture)-MS (mass spectrometry).
HepG2 cells cultured in d3-labeled DMEM medium were passaged for more than ten generations to reach an enough high labeling ratio. MTT assay was used to assess the inhibitory effect of quercetin on proliferation of HepG2 cells. In SILAC, total protein was extracted from control HepG2 cells and those treated by 50 µmol/L quercetin for 48 h, and then mixed to a 1:1 ratio. After in-gel digestion and idenfication by LC-MS/MS analysis, quantification informations of changed proteins were acquired by searching on Mascot 2.0 program (MatrixScience Ltd., London) against SWISS-PROT protein database. To ensure a high confidence level for identification, those peptides with Mascot scores below the threshold value were excluded from analysis and not included in the list of quantified proteins (P < 0.01). Protein abundance was calculated as ratios of the peak intensity of the fragment ions from the labeled versus the unlabeled peptides. RT-PCR was uesd to verify the reliability of HSPs changes by quercetin treatment from the SILAC-MS results.
After passaged for ten generations, the d3-labeling ratio was above 95%. MTT showed that quercetin inhibited the proliferation of HepG2 cells obviously, with a IC(50) close to 50 µmol/L, and in a dose-dependent and time-dependent manner. The MS showed that the expression of almost all heat shock family proteins was down-regulated a lot. The expression of HSP90 exposed to quercetin for 48 h was decreased to 49.3% of the normal HepG2 cells, and the expression of HSP70 was decreased to 43.6% of the normal Hep G2 cells. Quantitation information showed that the expression of HSP90α, HSP76, HSP60 and HSP27 was declined to 59.3%, 44.2%, 51.3% and 62.6%, respectively. Those results demonstrated that the quantification for changed protiens by SILAC-MS was correct.
Quercetin can exert a significant inhibitory effect on whole expression of heat shock proteins in HepG2 cells. We suppose this maybe one of the pathways through which quercetin plays an important anti-tumor role. SILAC-MS is a reliale technique and can be used to quantify the changes of whole protein spectrum in HepG2 cells before and after treatment with some exogeneous factors.
Zhonghua zhong liu za zhi [Chinese journal of oncology] 10/2011; 33(10):737-41.
ABSTRACT: To determine the associations between the polymorphisms of N372H in BRCA2 gene and 135G/C in RAD51 gene and breast cancers.
The allele and genotype frequencies of N372H in BRCA2 gene and 135G/C in RAD51 gene were analyzed with denaturing high performance liquid chromatography (DHPLC) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 71 women with breast cancers and 85 normal, women.
The women with breast cancers had higher frequencies of genotype HH of the N372H locus in BRCA2 gene than the normal women. No statistical difference in the polymorphic distribution of 135G/C in RAD51 gene was observed between the two groups of women.
The genotype HH of the N372H locus in BRCA2 is associated with breast cancers, which might be a genetic risk factor for breast cancers in Chinese populations.
Sichuan da xue xue bao. Yi xue ban = Journal of Sichuan University. Medical science edition 12/2008; 39(6):973-5.
ABSTRACT: Morphine sulfate controlled-released tablet and morphine hydrochloride sustained-released tablet are preferred medicines for treating moderate-severe cancer pain. There are some differences between the two medicines in their efficacy, metabolism and adverse events. This study was to compare the efficacy and toxicities between morphine sulfate controlled-released tablet and morphine hydrochloride sustained-released tablet in treating moderate-severe cancer pain.
A total of 121 patients with moderate-severe cancer pain were randomized into two groups: 61 were treated with morphine sulfate controlled-released tablet and 60 were treated with morphine hydrochloride sustained-released tablet. Analgesic efficacy and toxicities of the two medicines were observed.
Of the 61 patients treated with morphine sulfate controlled-released tablet, 12 had moderate pain, 49 had severe pain; the total response rate was 91.80%. Of the 60 patients treated with morphine hydrochloride sustained-released tablet, 13 had moderate pain, 47 had severe pain; the total response rate was 91.67%. There was no significant difference in the efficacy between the two medicines. Digestive system adverse events, including nausea, vomiting and constipation, were more common in morphine hydrochloride sustained-released tablet group than in morphine sulfate controlled-released tablet group (66.66% vs. 34.43%, P<0.05).
Both morphine sulfate controlled-released tablet and morphine hydrochloride sustained-released tablet are safety in treating moderate-severe cancer pain and the toxicities are tolerable. We recommend to take morphine sulfate controlled-released tablet for older patients and the patients with digestive disorders.
Ai zheng = Aizheng = Chinese journal of cancer 01/2008; 26(12):1357-9.
ABSTRACT: Vinorelbine (NVB) and oxaliplatin (OXA) have shown effective anticancer activity in a wide range of solid tumors. This study is to observe the efficacy and side effects of OXA in combination with NVB in the treatment of advanced non-small cell lung cancer (NSCLC).
Fifty-nine patients with NSCLC were randomly treated by OXA+NVB or cisplatin (DDP)+NVB regimen, repeated every 3-4 weeks. They received at least 2 cycles of chemotherapy.
There were 29 patients treated with NO regimen, in which there was no complete response (CR) patient, 12 patients showed partial response (PR), and the response rate was 41.4%. There were 30 patients treated with NP regimen. One patient showed CR, 13 patients showed PR, and the response rate was 46.7%. There was no significant difference in response rate between the two groups (P > 0.05). The major toxicities, including leukopenia and phlebitis, were similar in the two groups. The incidences of gastrointestinal reaction and alopecia of NP regimen were more severe than those of NO regimen (P < 0.05), but neurotoxicity of NO regimen was more obvious than that of NP regimen (P < 0.05).
The efficacy of the two regimens are similar in the treatment of advanced NSCLC. The side effects such as leukopenia and phlebitis are similar in the two groups. However, there are significant differences in gastrointestinal reaction, alopecia and neurotoxicity between the two groups. All the toxicities are well tolerable.
Zhongguo fei ai za zhi = Chinese journal of lung cancer 06/2005; 8(3):227-9.