Camptothecin (Standard) (Campathecin (Standard)) is the analytical standard of Camptothecin (HY-16560). This product is intended for research and analytical applications. Camptothecin (CPT), a kind of alkaloid, is a DNA topoisomerase I (Topo I) inhibitor with an IC50 of 679 nM. Camptothecin (CPT) exhibits powerful antineoplastic activity against colorectal, breast, lung and ovarian cancers, modulates hypoxia-inducible factor-1alpha (HIF-1alpha) activity by changing microRNAs (miRNA) expression patterns in human cancer cells.