Design, synthesis, and biological evaluation of novel azaspirooxindolinone derivatives as potent inhibitors of ITK and BTK-positive cancers

Bruton's tyrosine kinase (BTK) and Interleukin-2-inducible T-cell kinase (ITK) are two important members of the Tec family with crucial roles in immune system function. Deregulation in ITK and BTK activity is linked to several hematological malignancies, making them key targets for cancer immunotherapy. In this study, we synthesized new azaspirooxindolinone derivatives and evaluated their cytotoxic activity against ITK/BTK-negative and -positive cancer cell lines. Compounds 3d and 3j exhibited high cytotoxicity in both ITK-positive Jurkat (IC50 = 3.58 µM and 4.16 µM, respectively) and BTK-positive Ramos (IC50 = 3.06 µM and 1.38 µM, respectively) cell lines, indicating their potential dual activity against ITK and BTK. 3a and 3e showed high cytotoxicity specifically in ITK-positive Jurkat cells with IC50 values of 9.36 µM and 10.85 µM, respectively. Compounds 3f and 3g were highly cytotoxic specifically in Ramos cells with IC50 values of 1.82 µM and 1.42 µM, respectively. None of the active compounds exhibited cytotoxic effects against non-cancer cell lines (IC50 > 50 µM). These findings suggest that the synthesized azaspirooxindolinone derivatives, particularly compounds 3d and 3j, hold promise as dual inhibitors for ITK and BTK-positive cancers, while compounds 3a, 3e, 3f, and 3g demonstrate potential as specific inhibitors, warranting further investigation.