Discovery and characterization of a sophoridine-derived TNIK inhibitor with antitumor activity in hepatocellular carcinoma.

Natural product scaffolds provide structurally distinctive starting points for anticancer small-molecule discovery, yet connecting phenotype-guided optimization with molecular target identification remains challenging. Here, focused diversification of a previously reported sophoridine-derived aminoquinoline scaffold, followed by cell-based screening, led to the identification of YM17 as a potent anti-hepatocellular carcinoma (HCC) analogue. YM17 inhibited HuH-7 cell proliferation with an IC50 value of 0.50 μM and exhibited antitumor activity across cellular phenotypic assays and an HCC xenograft model. Single-temperature thermal proteome profiling nominated TNIK as a candidate target of YM17. Orthogonal validation showed that YM17 increased the thermal stability of TNIK in cells, inhibited recombinant TNIK kinase activity with an IC50 value of 181.9 nM, and bound to TNIK in a surface plasmon resonance assay. Mechanistic analyses further revealed changes in TNIK-associated proliferative signaling and apoptosis-regulatory proteins that were consistent with the observed anti-HCC phenotype. Collectively, these findings identify YM17 as a potent sophoridine-derived TNIK inhibitor with cellular target engagement and in vivo anti-HCC activity. This work also highlights the value of integrating phenotype-guided natural product scaffold diversification with proteome-scale target deconvolution for anticancer lead discovery.