A MICRODISSECTION TECHNIQUE FOR ARCHIVAL DNA ANALYSIS OF SPECIFIC CELL-POPULATIONS IN LESIONS LESS-THAN-1 MM IN SIZE

We have developed a microdissection technique that allows for procurem ent and analysis of specific, minute cell populations from routine, 5- mu, formalin-fixed, paraffin-embedded histological tissue sections, Le sions <1 mm in size can be specifically examined Cells of interest are procured tender direct microscopic visualization followed by a single -step DNA extraction and subsequent polymerase chain reaction. Amplifi cation of DNA from selected cell populations was demonstrated by detec ting a loss of heterozygosity (LOH) at the von Hippel-Lindau disease ( VHL) gene in an atypical renal lesion and a renal cell carcinoma in a kidney of a VHL patient, Moreover, previously unrecognized LON on the short arm of chromosome 3 (3p25-26) was detected in microdissected col orectal carcinoma cells he a non-VHL patient with sporadic colon carci noma This technique should prove useful in DNA studies of small lesion s and cell populations. Furthermore, microscopic premalignant, in situ , and invasive lesions can be selectively examined.