NVP-TNKS656 is a potent and selective inhibitor of tankyrase enzymes (TNKS1 and TNKS2), which play a key role in the Wnt/β-catenin signaling pathway. This pathway is frequently dysregulated in certain cancers, particularly colorectal cancers with APC mutations. By inhibiting tankyrase, NVP-TNKS656 promotes the stabilization of the β-catenin destruction complex, leading to reduced levels of nuclear β-catenin and suppression of downstream oncogenic gene expression. Its primary application is in cancer research, especially as a tool compound to study Wnt pathway dependency in tumor models. It has demonstrated anti-proliferative effects in cancer cell lines with hyperactive Wnt signaling. Additionally, it is used to investigate the role of tankyrase in telomere maintenance and PARsylation-related cellular processes. Due to its selectivity and pharmacokinetic properties, it serves as a valuable lead molecule for developing targeted cancer therapies, although it remains primarily a preclinical research agent.