Spectroscopic Signature of Apoptosis Induced by Venetoclax in Philadelphia-Positive Acute Lymphoblastic Leukemia.

Understanding why some leukemia cells undergo apoptosis upon venetoclax (VEN) treatment while others remain refractory is essential for improving therapeutic outcomes. Here, we integrate Raman microscopy, FT-IR imaging, and chemometrics to explore treatment-associated spectroscopic patterns linked to differential VEN response in Philadelphia-positive B-cell acute lymphoblastic leukemia (Ph+ B-ALL). Using two BCR-ABL1-positive cell lines with intrinsic differences in VEN sensitivity (BV-173, sensitive; SD-1, resistant), we combined classical biological readouts of apoptosis with multimodal vibrational profiling to characterize global biochemical changes induced by VEN. Sensitive BV-173 cells displayed spectroscopic changes consistent with apoptotic progression, reflected in coordinated alterations in nucleic acids, proteins, and lipids. In contrast, resistant SD-1 cells exhibited a distinct treatment-associated biochemical response profile consistent with nonapoptotic adaptation. Spectroscopic fingerprints enabled differentiation between apoptotic and nonapoptotic response patterns in the cell-line models studied. Our findings demonstrate that vibrational spectroscopy, integrated with chemometrics, may provide a complementary analytical framework for exploratory characterization of treatment-associated biochemical phenotypes in leukemia.