IDENTIFICATION OF DIFFERENTIALLY EXPRESSED RNA IN HUMAN OVARIAN-CARCINOMA CELLS BY ARBITRARILY PRIMED PCR FINGERPRINTING OF TOTAL RNAS

Using arbitrarily primed PCR fingerprinting of RNA (RAP), we have analyzed RNAs prepared from two normal ovarian surface epithelial cell cultures, two normal mesothelial cell cultures, and eight independent ovarian carcinoma cell lines. Each arbitrarily chosen primer gave a unique fingerprint of about 30 cDNA products. Most of the cDNA products produced by any particular primer were shared between all cell lines. However, one primer detected a cDNA PCR product that was absent in all eight ovarian carcinoma cell lines but present in all normal cell cultures. We have cloned and sequenced the DNA fragment that distinguishes normal from ovarian carcinoma cell lines. The DNA sequence has one continuous open reading frame throughout which indicates that it may be from a translated gene. Furthermore, we confirmed the differential expression of the gene by Northern blot analysis. We also observed that the intensity of the band in the RNA fingerprint correlates with the expression level of the corresponding RNA. These results further demonstrate the ability of RAP to detect differentially expressed genes in a quantitative manner and demonstrated the application of RAP for the detection of differential gene expression during carcinogenesis.