Figure 1. SUV39H2 is overexpressed in human lung cancer.

(a) In vitro methyltransferase analysis of SUV39H2. Recombinant histone H2AX and ³H-SAM were incubated in the presence or absence of recombinant SUV39H2, and the reaction products were analysed by SDS–PAGE followed by fluorography (upper panel) and stained for total protein(lower panel). (b) SUV39H2 mRNA levels in 14 lung cancer cases (NSCLC: 9 cases; SCLC: 5 cases) and 16 normal tissues. (c) Quantitative real-time PCR analysis was performed in 14 lung cancer samples and 16 normal tissues (the brain, breast, colon, oesophagus, eye, heart, liver, pancreas, rectum, spleen, stomach, kidney, bladder, testis, placenta and lung) and the result is shown by box-whisker plot. For statistical analysis, Kruskal–Wallis (*P<0.05) and Student’s t-test (**P<0.05) were performed. (d) Representative cases for positive SUV39H2 expression in lung cancer tissues and normal adult tissues. ADC, adenocarcinoma; SCC, squamous cell carcinoma. Original magnification, × 100 (lung × 200). (e) Expression levels of SUV39H2 in 65 normal lung samples, 19 large cell lung carcinoma samples, 45 lung adenocarcinoma samples and 27 squamous cell lung carcinoma samples. SUV39H2 is overexpressed in all three types of lung cancer. Expression profile is derived from Oncomine database.