Figure 1

MTAP expression in colon carcinoma cell lines compared to primary human CEC and the highly differentiated cell line HT29M3. (a) The amount of MTAP mRNA expression was carefully quantified by real-time PCR. All colon carcinoma cell lines showed a strong expression of MTAP compared to human primary hepatocytes and melanocytes that served as control. Isolated primary human CEC of six different donors showed almost no MTAP expression comparable to the weak expression in melanoma cells.²¹ (b) By real-time PCR it was shown that the amount of MTAP mRNA expression in HT29M3 resembles the weak expression in primary human CEC. Data shown represents the mean of three experiment (±s.d.). MTAP expression in CaCo-2 was set as 1. (c) By microsatellite analysis of 9p21 a biallelic amplification in all but one colorectal cancer cell line (SW480) was shown. (d) By RT-PCR amplification expression of p15 and p16 in the colon carcinoma cell lines was analysed. All colon carcinoma cell lines showed expression of p15 and p16.