Given the task definition and input, reply with output. Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Context: Imatinib mesylate, a BCR-ABL tyrosine kinase inhibitor, induces apoptosis in chronic myeloid leukemia cells. Resistance to imatinib is currently the most important concern of this treatment. One of the main mechanisms of this resistance is overexpression of BCR-ABL.', 'In the current study, the authors investigated the correlation between BCR-ABL overexpression and apoptosis in BaF/BCR-ABL and LAMA84 cell lines resistant to imatinib suddenly deprived of the inhibitor, and compared with their sensitive counterpart.', 'Removal of imatinib from culture medium led to a decrease in Bcr-Abl protein expression by Day 5, which was sustained for > or = 3 weeks of imatinib deprivation. Apoptosis was observed after 3 days of imatinib deprivation in resistant lines accompanied by caspase activation, loss of membrane asymmetry (annexin V staining), and alteration of mitochondrial potential (dihexyloxacarbocyanine iodide [DiOC6]). Transient activation of the STAT5/Bcl-xL pathway and Akt kinase activity preceded these responses.
Answer: Thus, imatinib removal led to apoptosis of BCR-ABL-overexpressing leukemic cells, a phenomenon that could be exploited to sensitize imatinib-resistant cells to the cytotoxic effect of other drugs.

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Does overproduction of BCR-ABL induce apoptosis in imatinib mesylate-resistant cell lines?