Design, Synthesis, And Evaluation Of Cyanopyridines As Anti-Colorectal Cancer Agents Via Inhibiting STAT3 Pathway.

BACKGROUND: Colorectal cancer is one of the common malignant tumors. Cyanopyridine and aminocyanopyridine having a carbon-nitrogen bond have been shown to have significant anticancer effects. STAT3 is a promising therapeutic target in multiple cancers. However, there are currently no effective STAT3 inhibitors in clinical practice for the treatment of colorectal cancer. MATERIALS AND METHODS: We screened 27 cyanopyridines for their anticancer activity by cell viability. The HCT-116, RKO, and DLD-1 cell lines were used to evaluate the anti-colorectal cancer effect of 3n. Scratch experiments and colony formation assays were used for the assessment of cell migration and proliferation capacity. Phosphorylated STAT3, STAT3, MCL-1, and Survivin levels were assessed by Western blot analysis. RESULTS: In this study, we synthesized 27 cyanopyridines and screened their anticancer activities in three human tumor cells, HCT-116, Hela229, and A375. We found that 2-amino-3-cyanopyridine 3n has better anticancer activity with IC50 values in the low micromolar range. Furthermore, 3n significantly inhibited the migration and colony formation of colorectal cancer cells. Mechanistically, 3n inhibited the expression of STAT3 phosphorylation in a dose- and time-dependent manner. CONCLUSION: 3n is worth of further investigations toward the discovery of STAT3 inhibitor as a drug candidate for cancer therapy.

Aminocyanopyridines as anti-lung cancer agents by inhibiting the STAT3 pathway.

Lung cancer is a leading cause of cancer-related death worldwide. Cyanopyridines and aminocyanopyridines with carbon-nitrogen bonds have been proved to exert significant anticancer, antibacterial, and anti-inflammatory effects. In this study, we showed that aminocyanopyridine 3o and 3k displaying potent antitumor activity via inhibiting the signal transducer and activator of transcription 3 (STAT3) pathway. They blocked the constitutive STAT3 phosphorylation in a dose- and time-dependent manner and regulated the transcription of STAT3 target genes encoding apoptosis factors. Most importantly, 3o also inhibited interleukin-6-induced STAT3 activation and nuclear localization. Furthermore, 3o significantly inhibited the tumor growth of H460-derived xenografts. Taken together, these findings suggest that 3o and 3k are promising therapeutic drug candidates for lung cancer by inhibiting persistent STAT3 signaling.