gemcitabine + etoposide + cisplatin

Gemcitabine + etoposide + cisplatin is a combination chemotherapy regimen consisting of three small molecule cytotoxic agents. Gemcitabine is a nucleoside analog that inhibits DNA synthesis by incorporation into DNA and inhibition of ribonucleotide reductase, leading to cell cycle arrest and apoptosis. Etoposide is a topoisomerase II inhibitor that causes DNA strand breaks by stabilizing the enzyme-DNA complex, preventing religation of the DNA strands. Cisplatin is a platinum-based compound that forms crosslinks in DNA, interfering with replication and transcription, ultimately triggering apoptosis. This combination has been studied primarily for advanced or metastatic cancers such as urothelial carcinoma and non-small-cell lung cancer (NSCLC), where it has demonstrated significant antitumor activity but also notable bone marrow toxicity[2][3][5].