Resistance to tyrosine kinase inhibitors (TKIs) remains a clinical challenge in Ph-positive variants of chronic myeloid leukemia. We provide mechanistic insights into a previously undisclosed MEK1/2/BCR::ABL1/BCR/ABL1-driven signaling loop that may determine the efficacy of arsenic trioxide (ATO) in TKI-resistant leukemic patients. We find that activated MEK1/2 assemble into a pentameric complex with BCR::ABL1, BCR and ABL1 to induce phosphorylation of BCR and BCR::ABL1 at Tyr360 and Tyr177, and ABL1, at Thr735 and Tyr412 residues thus provoking loss of BCR's tumor-suppression functions, enhanced oncogenic activity of BCR::ABL1, cytoplasmic retention of ABL1 and consequently drug resistance.
View Article and Find Full Text PDFTriple negative breast cancers (TNBCs) represent about 15-20% of all breast cancer cases and are characterized by a complex molecular heterogeneity. Some TNBCs exhibit clinical and pathological properties similar to BRCA-mutated tumors, without actually bearing a mutation in BRCA genes. This "BRCAness" phenotype may be explained by germline mutations in other genes involved in DNA repair.
View Article and Find Full Text PDFBRCA1 interacts with several proteins implicated in homologous and non homologous recombination and in mismatch repair. The aim of this study is to determine if MSH2, a well known partner of BRCA1 involved in DNA repair, may contribute to breast and ovarian cancer development and progression. To better understand the functional interaction between BRCA1 and MSH2, we studied the effect of the deletion of MSH2 gene on BRCA1-induced genome instability in yeast.
View Article and Find Full Text PDFTherapy-related myeloid neoplasms (t-MN) are a complication of cytotoxic treatment for primary tumors and autoimmune diseases. We report data on 277 t-MN patients, recruited between 1999 and 2013 by the Italian Network on Secondary Leukemias (104 retrospectively and 173 prospectively registered). Median age at t-MN diagnosis was 64 years (range, 21-87).
View Article and Find Full Text PDFJ Antimicrob Chemother
April 2014
Objectives: Micafungin inhibits 1,3-β-D-glucan synthase and interferes with fungal cell wall synthesis. Clinically, micafungin has been shown to be efficacious for the treatment of invasive fungal infections. However, little is known about the immunomodulatory activity of micafungin in these infections.
View Article and Find Full Text PDFThe mammalian target of rapamycin (mTOR) signalling pathway has emerged as an important therapeutic target for acute myeloid leukaemia (AML). This study assessed the combination of temsirolimus, an mTOR inhibitor, and lower-dose clofarabine as salvage therapy in older patients with AML. Induction consisted of clofarabine 20mg/m(2) on days 1-5 and temsirolimus 25mg (flat dose) on days 1, 8 and 15.
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