Topoisomerase I (topo I) inhibitors are promising anticancer agents with demonstrated activity against a wide range of solid tumors. Quantitative information on topol mRNA levels in tumor biopsies may predict response to topo I inhibitors. Materials and methods: A polymerase chain reaction aided transcript titration assay (PATTY) was developed to allow quantitation of topol mRNA in small samples. Concentrations of topol mRNA in total RNA samples were estimated by RT-PCR analysis in a human small cell lung cancer (SCLC) cell line (GLC,) and its topotecan (GL(2)C/SK and F) and camptothecin (GL(2)C/Campt) resistant sublines, human nonsmall cell lung cancer (NSCLC) and ovarian carcinoma samples. Results: Topol PATTY showed a decreased topo I mRNA level in GLC(2)/SK and F (4.5 pg/100 ng total RNA) and GLC,/Campt (2.2 pg/100 ng total RNA), respectively, compared to the parent cell line GLC(2) (5.4 pg/100 ng total RNA). Topol protein levels as measured by Western blotting were compatible with topol mRNA levels. Median (range) topol mRNA levels were 3.23 (2.33-5.10) pg/100 ng total RNA in resected NSCLC specimen (n=6), and 2.03 (0.54-0.95) pg/100 ng total RNA in resected ovarian cancer specimen (n=6). Conclusion: We conclude that topol PATTY is a new assay that quantitates topol mRNA levels in cell lines and small tumor samples.
|Number of pages||7|
|Publication status||Published - 1999|
- topoisomerase I gene expression
- human tumor specimen
- POLYMERASE CHAIN-REACTION
- CANCER CELL-LINE
- CATALYTIC ACTIVITY