ANALYSIS OF REPRODUCIBILITY OF A NONRADIO ACTIVE DDRT-PCR-METHOD FOR DETECTION OF GENE-EXPRESSION IN SQUAMOUS-CELL CARCINOMA-CELLS FROM TUMORS OF THE UPPER AERODIGESTIVE TRACT

Background: The analysis of the gene spectrum in tumor and normal cell s may provide information about genes involved in the differentiation or in the genesis of tumors. Differential Display Reverse Transcriptas e Polymerase Chain Reaction (DDRT-PCR) is an innovative method that en ables quick analysis of almost all mRNA molecules expressed in the cel ls. Methods: In the trials, the mRNAs of keratinocytes and tumor cells were amplified by a number of oligonucleotide pairs after reverse tra nscription and resolved on polyacrylamide gel. A modified protocol for the amplification of cDNA probes was devised for detecting PCR produc ts with silver nitrate. Results: After reverse transcription of mRNAs, all cDNA samples were successfully amplified using the protocol devis ed for the silver nitrate DDRT-PCR, and the differentially expressed f ragments were reproducibly demonstrated. Conclusions: The high reprodu cibility and feasibility of silver nitrate DDRT-PCR expand the alterna tives for analyzing gene expression and detecting selectively expresse d genes in different kinds of cells.