Use of suppression subtractive hybridization strategy for cloning and identifying specifically expressed genes of renal cell carcinoma

Using suppression subtractive hybridization, a renal cell carcinoma (RCC) c DNA subtractive library which only contains differently expressed cDNAs bet ween human RCC and normal kidney has been constructed, 200 clones were pick ed out randomly to perform enzyme digest analysis, a part Of them underwent sequence analysis and Northern blot to:identify RCC specially expressed ge nes. Results showed that 190 clones contain 50-400 bp inserts respectively, Sequence analysis was performed in 10 clones. All the 10 sequences were un known before and derived from 6 unique novel genes among which the cDNA ins ert RCC18 has five copies. Northern blot analysis showed that RCC18 cDNA ex pressed highly in RCC, but there was no signal detected in normal kidney, a nd the full length of RCC18 was about 2.5 kb. The constructed cDNA subtract ive library of human RCC is a highly efficient one and lays the solid found ation for large-scale screening and cloning new and specific oncogenes or t umor suppressor genes of RCC. The novel specially expressed genes provided an important clue for researching the mechanism of the occurrence and devel opment of RCC.