Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P17931 (galectin-3)
 2,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antiapoptotic molecule galectin-3 was previously shown to regulate CD95, a member of the tumor necrosis factor (TNF) family of proteins in the apoptotic signaling pathway. Here, we question the generality of the phenomenon by studying a different member of this family of proteins [e.g., TNF-related apoptosis-inducing ligand (TRAIL), which induces apoptosis in a wide variety of cancer cells]. Overexpression of galectin-3 in J82 human bladder carcinoma cells rendered them resistant to TRAIL-induced apoptosis, whereas phosphatidylinositol 3-kinase (PI3K) inhibitors (wortmannin and LY-294002) blocked the galectin-3 protecting effect. Because Akt is a major downstream PI3K target reported to play a role in TRAIL-induced apoptosis, we questioned the possible relationship between galectin-3 and Akt. Parental J82 and the control vector-transfected J82 cells (barely detectable galectin-3) exhibit low level of constitutively active Akt, resulting in sensitivity to TRAIL. On the other hand, J82 cells overexpressing galectin-3 cells expressed a high level of constitutively active Akt and were resistant to TRAIL. Moreover, the blockage of TRAIL-induced apoptosis in J82 cells seemed to be mediated by Akt through the inhibition of BID cleavage. These results suggest that galectin-3 involves Akt as a modulator molecule in protecting bladder carcinoma cells from TRAIL-induced apoptosis.
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PMID:Galectin-3 inhibits tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis by activating Akt in human bladder carcinoma cells. 1614 Sep 16

GCS-100 is a galectin-3 antagonist with an acceptable human safety profile that has been demonstrated to have an antimyeloma effect in the context of bortezomib resistance. In the present study, the mechanisms of action of GCS-100 are elucidated in myeloma cell lines and primary tumor cells. GCS-100 induced inhibition of proliferation, accumulation of cells in sub-G(1) and G(1) phases, and apoptosis with activation of both caspase-8 and -9 pathways. Dose- and time-dependent decreases in MCL-1 and BCL-X(L) levels also occurred, accompanied by a rapid induction of NOXA protein, whereas BCL-2, BAX, BAK, BIM, BAD, BID, and PUMA remained unchanged. The cell-cycle inhibitor p21(Cip1) was up-regulated by GCS-100, whereas the procycling proteins CYCLIN E2, CYCLIN D2, and CDK6 were all reduced. Reduction in signal transduction was associated with lower levels of activated IkappaBalpha, IkappaB kinase, and AKT as well as lack of IkappaBalpha and AKT activation after appropriate cytokine stimulation (insulin-like growth factor-1, tumor necrosis factor-alpha). Primary myeloma cells showed a direct reduction in proliferation and viability. These data demonstrate that the novel therapeutic molecule, GCS-100, is a potent modifier of myeloma cell biology targeting apoptosis, cell cycle, and intracellular signaling and has potential for myeloma therapy.
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PMID:GCS-100, a novel galectin-3 antagonist, modulates MCL-1, NOXA, and cell cycle to induce myeloma cell death. 2019 Jan 89

PP2A activator FTY720 has been shown to possess the anti-leukemic activity for chronic myelogenous leukemia (CML), however, the cell killing mechanism underlying its anti-leukemic activity has remained to be verified. We investigated the precise mechanisms underlying the apoptosis induction by FTY720, especially focusing on the roles of BH3-only proteins, and the therapeutic potency of FTY720 for CML. Enforced expression of either BCL2 or the dominant-negative protein of FADD (FADD.DN) partly protected CML cells from apoptosis by FTY720, indicating the involvement of both cell extrinsic and intrinsic apoptosis pathways. FTY720 activates pro-apoptotic BH3-only proteins: BIM, which is essential for apoptosis by BCR-ABL1 tyrosine kinase inhibitors (TKIs), and BID, which accelerates the extrinsic apoptosis pathway. Gene knockdown of either BIM or BID partly protected K562 cells from apoptosis by FTY720, but the extent of cell protection was not as much as that by overexpression of either BCL2 or FADD.DN. Moreover, knockdown of both BIM and BID did not provide additional protection compared with knockdown of only BIM or BID, indicating that BIM and BID complement each other in apoptosis by FTY720, especially when either is functionally impaired. FTY720 can overcome TKI resistance caused by ABL kinase domain mutations, dysfunction of BIM resulting from gene deletion polymorphism, and galectin-3 overexpression. In addition, ABT-263, a BH3-mimetic, significantly augmented cell death induction by FTY720 both in TKI-sensitive and -resistant leukemic cells. These results provide the rationale that FTY720, with its unique effects on BIM and BID, could lead to new therapeutic strategies for CML.
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PMID:FTY720 induces apoptosis of chronic myelogenous leukemia cells via dual activation of BIM and BID and overcomes various types of resistance to tyrosine kinase inhibitors. 2385 82