AIM:To investigate large tumor suppressor 1 (LATS1 ) expression, promoter hypermethylation, and microsatellite instability in colorectal cancer (CRC).METHODS:RNA was isolated from tumor tissue of 142 CRC patients and ...AIM:To investigate large tumor suppressor 1 (LATS1 ) expression, promoter hypermethylation, and microsatellite instability in colorectal cancer (CRC).METHODS:RNA was isolated from tumor tissue of 142 CRC patients and 40 colon mucosal biopsies of healthy controls. After reverse transcription, quantitative polymerase chain reaction (PCR) was performed, and LATS1 expression was normalized to expression of the ACTB and RPL32 housekeeping genes. To analyze hypermethylation, genomic DNA was isolated from 44 tumor CRC biopsies, and methylation-specific PCR was performed. Microsatellite instability (MSI) status was checked with PCR using BAT26, BAT25, and BAT40 markers in the genomic DNA of 84 CRC patients, followed by denaturing gel electrophoresis. RESULTS:Decreased LATS1 expression was found in 127/142 (89.4%) CRC cases with the average ratio of the LATS1 level 10.33 ± 32.64 in CRC patients vs 32.85 ± 33.56 in healthy controls. The lowest expression was found in Dukes' B stage tumors and G1 (welldifferentiated) cells. Hypermethylation of the LATS1 promoter was present in 25/44 (57%) CRC cases analyzed. LATS1 promoter hypermethylation was strongly associated with decreased gene expression; methylated cases showed 162× lower expression of LATS1 than unmethylated cases. Although high-grade MSI (mutation in all three markers) was found in 14/84 (17%) cases and low-grade MSI (mutation in 1-2 markers) was found in 30/84 (36%) cases, we found no association with LATS1 expression. CONCLUSION:Decreased expression of LATS1 in CRC was associated with promoter hypermethylation, but not MSI status. Such reduced expression may promote progression of CRC.展开更多
AIM: To assess the absolute number of T-regulatory cells (Tregs; CD4+CD25+Foxp3+) in the peripheral blood of gastric and colorectal cancer patients. METHODS: We enrolled 70 cancer patients (33 gastric cancer, 37 color...AIM: To assess the absolute number of T-regulatory cells (Tregs; CD4+CD25+Foxp3+) in the peripheral blood of gastric and colorectal cancer patients. METHODS: We enrolled 70 cancer patients (33 gastric cancer, 37 colorectal cancer) and 17 healthy volunteers. The CD3+CD4+ lymphocytes and CD4+CD25+Foxp3+ Tregs in the peripheral blood were analyzed with flow cytometry. The absolute numbers of Tregs were calculated based on the CD4+CD25+Foxp3+ cells percent-age of CD3+CD4+ cells and the absolute numbers of CD3+CD4+ cells per microliter. RESULTS: The mean number of CD4+CD25+Foxp3+ cells per microliter in colorectal cancer patients was 15.7 (SD: 21.8), for gastric cancer patients 12.2 (SD: 14.3), and for controls 17.5 (SD: 11.4). The absolute number of Tregs was significantly lower in gastric cancer patients than in controls (P = 0.026). There was no statistically significant difference for gastric vs colorectal cancer or colorectal cancer vs controls. The absolute number of Tregs was also significantly depressed in N+ vs Ncancer patients [22.0 (27.7) vs 10.1 (9.0), P = 0.013], and in the subgroup of gastric cancer patients [30.3 (27.6) vs 9.6 (8.0), P = 0.003]. No statistical difference was observed in the proportion of Tregs in the CD4+ population between the groups. CONCLUSION: The absolute number of Tregs in peripheral blood of gastric cancer but not colorectal cancer patients was significantly decreased in comparison with that in healthy controls.展开更多
基金Supported by Polish Ministry of Science, No. N N402 683940
文摘AIM:To investigate large tumor suppressor 1 (LATS1 ) expression, promoter hypermethylation, and microsatellite instability in colorectal cancer (CRC).METHODS:RNA was isolated from tumor tissue of 142 CRC patients and 40 colon mucosal biopsies of healthy controls. After reverse transcription, quantitative polymerase chain reaction (PCR) was performed, and LATS1 expression was normalized to expression of the ACTB and RPL32 housekeeping genes. To analyze hypermethylation, genomic DNA was isolated from 44 tumor CRC biopsies, and methylation-specific PCR was performed. Microsatellite instability (MSI) status was checked with PCR using BAT26, BAT25, and BAT40 markers in the genomic DNA of 84 CRC patients, followed by denaturing gel electrophoresis. RESULTS:Decreased LATS1 expression was found in 127/142 (89.4%) CRC cases with the average ratio of the LATS1 level 10.33 ± 32.64 in CRC patients vs 32.85 ± 33.56 in healthy controls. The lowest expression was found in Dukes' B stage tumors and G1 (welldifferentiated) cells. Hypermethylation of the LATS1 promoter was present in 25/44 (57%) CRC cases analyzed. LATS1 promoter hypermethylation was strongly associated with decreased gene expression; methylated cases showed 162× lower expression of LATS1 than unmethylated cases. Although high-grade MSI (mutation in all three markers) was found in 14/84 (17%) cases and low-grade MSI (mutation in 1-2 markers) was found in 30/84 (36%) cases, we found no association with LATS1 expression. CONCLUSION:Decreased expression of LATS1 in CRC was associated with promoter hypermethylation, but not MSI status. Such reduced expression may promote progression of CRC.
基金Supported by Ministry of Science and Higher Education of Poland Grants 2P05C 001 29 and K/PBW/000421
文摘AIM: To assess the absolute number of T-regulatory cells (Tregs; CD4+CD25+Foxp3+) in the peripheral blood of gastric and colorectal cancer patients. METHODS: We enrolled 70 cancer patients (33 gastric cancer, 37 colorectal cancer) and 17 healthy volunteers. The CD3+CD4+ lymphocytes and CD4+CD25+Foxp3+ Tregs in the peripheral blood were analyzed with flow cytometry. The absolute numbers of Tregs were calculated based on the CD4+CD25+Foxp3+ cells percent-age of CD3+CD4+ cells and the absolute numbers of CD3+CD4+ cells per microliter. RESULTS: The mean number of CD4+CD25+Foxp3+ cells per microliter in colorectal cancer patients was 15.7 (SD: 21.8), for gastric cancer patients 12.2 (SD: 14.3), and for controls 17.5 (SD: 11.4). The absolute number of Tregs was significantly lower in gastric cancer patients than in controls (P = 0.026). There was no statistically significant difference for gastric vs colorectal cancer or colorectal cancer vs controls. The absolute number of Tregs was also significantly depressed in N+ vs Ncancer patients [22.0 (27.7) vs 10.1 (9.0), P = 0.013], and in the subgroup of gastric cancer patients [30.3 (27.6) vs 9.6 (8.0), P = 0.003]. No statistical difference was observed in the proportion of Tregs in the CD4+ population between the groups. CONCLUSION: The absolute number of Tregs in peripheral blood of gastric cancer but not colorectal cancer patients was significantly decreased in comparison with that in healthy controls.
