[Histone deacetylase inhibitor MS-275 treatment alters immune molecule content and categories in hepatocarcinoma exosomes].

OBJECTIVE: To investigate the effects of the histone deacetylase inhibitor, MS-275, on the immune molecule content and categories in hepatocarcinoma exosomes. METHODS: Exosomes were isolated from the human hepatocarcinoma cell lines, HepG2 and Hep3b, and purified by a combination technique of ultrafiltration centrifugation and sucrose gradient ultracentrifugation. The expressions of heat shock protein (HSP)70, human leukocyte antigen (HLA)-I, HLA-DR, cluster of differentiation (CD) 80 and NY-ESO-1 on exosomes were analyzed with immunoelectron microscopy and Western blotting before and after MS-275 treatment. Intergroup differences were statistically analyzed by the Student's paired t-test. RESULTS: MS-275 treatment of both HepG2 and Hep3b cell types significantly increased the numbers of exosomes, their total protein content, and expression of HSP70, HLA-I and CD80 (per 100 exosomes), as compared to non-treated cells (all, P less than 0.01). MS-275 was also found to induce de novo expression of HLA-DR, but had no significant effect on NY-ESO-1 expression (P more than 0.05). The findings from immunoelectron microscopy confirmed those from Western blotting. CONCLUSION: The histone deacetylase inhibitor, MS-275, can significantly alter the immune molecule content and categories in exosomes of hepatocarcinoma cells. The differential expression profile may reflect an anti-cancer immune response and represent molecular targets for novel anti-hepatoma therapeutic or preventative strategies.

[Advanced dermatofibrosarcoma protuberans treated with imatinib mesylate].

OBJECTIVE: To evaluate the efficacy, side effects and toxicity of imatinib mesylate in the treatment of patients with locally advanced and/or metastatic dermatofibrosarcoma protuberans (DFSP). METHODS: Twenty-four cases of advanced DFSP diagnosed by pathology and treated in our hospital from Nov. 2004 to Oct. 2009 were included in this study. The patients were treated with imatinib mesylate (dosage: 400 mg, po, qd) and carefully observed for treatment efficacy, side effects and survival time. There were 2 patients taking the drug as second line therapy, and other 22 patients as third or more than third line therapy. RESULTS: The 24 patients were evaluable for the efficacy. There were 8 patients (33.3%) with CR, 10 pts (41.7%) PR, 2 patients (8.3%) SD, and 4 patients (16.7%) PD. The disease control rate (DCR = CR+PR+SD) was 83.3%. The median response time in 18 cases with CR and PR was 5.6 months. The median survival time in 20 cases with disease control was 30 months, however, that in nonresponse (PD) cases was only 10 months. Side reactions related to imatinib mesylate included nausea and vomiting (20.8%), neutropenia (12.5%), and edema (8.3%). CONCLUSIONS: Our results are consistent with previous reports in the literature. Imatinib is a safe and effective moleucular target drug used for Chinese. Only mild adverse reactions occur in the treated patients. It is worth using imatinib in the treatment of advanced DFSP patients.

Effectiveness of circulating tumor DNA for detection of KRAS gene mutations in colorectal cancer patients: a meta-analysis.

Circulating tumor DNA (ctDNA) can be identified in the peripheral blood of patients and harbors the genomic alterations found in tumor tissues, which provides a noninvasive approach for detection of gene mutations. We conducted this meta-analysis to investigate whether ctDNA can be used for monitoring KRAS gene mutations in colorectal cancer (CRC) patients. Medline, Embase, Cochrane Library and Web of Science were searched for the included eligible studies in English, and data were extracted for statistical analysis according to the numbers of true-positive (TP), true-negative (TN), false-positive (FP) and false-negative (FN) cases. Sensitivity, specificity and diagnostic odds ratio (DOR) were calculated, and the area under the receiver operating characteristic curve (AUROC) was used to evaluate the diagnostic performance. After independent searching and reviewing, 21 studies involving 1,812 cancer patients were analyzed. The overall sensitivity, specificity and DOR were 0.67 (95% confidence interval [CI] =0.55-0.78), 0.96 (95% CI =0.93-0.98) and 53.95 (95% CI =26.24-110.92), respectively. The AUROC was 0.95 (95% CI =0.92-0.96), which indicated the high diagnostic accuracy of ctDNA. After stratified analysis, we found the higher diagnostic accuracy in subgroup of patients detected in blood sample of plasma. The ctDNA may be an ideal source for detection of KRAS gene mutations in CRC patients with high specificity and diagnostic value.

Effect of 5-aza-2'-deoxycytidine on immune-associated proteins in exosomes from hepatoma.

AIM: To study the effect of 5-aza-2'-deoxycytidine (5-aza-CdR) on heat shock protein 70 (HSP70), human leucocyte antigen-I (HLA-I) and NY-ESO-1 proteins in exosomes produced by hepatoma cells, HepG2 and Hep3B. METHODS: Exosomes derived from HepG(2) and Hep3B cells treated with or without 5-aza-CdR were isolated and purified by ultrafiltration centrifugation and sucrose gradient ultracentrifugation. The number of exosomes was counted under electron microscope. Concentration of proteins in exosomes was measured by bicinchoninic acid protein assay. Expression of HSP70, HLA-I and NY-ESO-1 proteins in exosomes was detected by Western blotting and immunoelectron microscopy. mRNA expression of p53 gene was detected by reverse transcription polymerase chain reaction. RESULTS: The mRNA expression of p53 gene was increased in both hepatoma cell lines after treatment with 5-aza-CdR. The number of exosomes and the concentration of total proteins in exosomes were increased significantly after treatment with 5-aza-CdR (P < 0.05). After treatment with 5-aza-CdR, immunoelectron microscopy and Western blotting showed that the HSP70, HLA-I and NY-ESO-1 proteins were increased in exosomes produced by both hepatoma cell lines. CONCLUSION: 5-Aza-CdR, an inhibitor of DNA methyltransferase, can increase exosomes produced by hepatoma cells and immune-associated protein component of exosomes, which may be mediated by p53 gene up-regulation and 5-aza-CdR demethylation.