ABSTRACT
Tumor necrosis factor receptor-related factor 7 (TRAF7) can regulate cell differentiation and apoptosis, but its specific functional mechanism in the pathological process of acute myeloid leukemia (AML) closely related to differentiation and apoptosis disorders is largely unclear. In this study, TRAF7 was found to be lowly expressed in AML patients and a variety of myeloid leukemia cells. TRAF7 was overexpressed in AML Molm-13 and chronic myeloid leukemia (CML) K562 cells by transfection with pcDNA3.1-TRAF7. CCK-8 assay and flow cytometry analysis showed that TRAF7 overexpression induced growth inhibition and apoptosis in K562 and Molm-13 cells. Measurements of glucose and lactate suggested that TRAF7 overexpression impaired glycolysis of K562 and Molm-13 cells. Cell cycle analysis indicated that most of K562 and Molm-13 cells were captured in G0/G1 phase by TRAF7 overexpression. PCR and western blot assay revealed that TRAF7 increased Kruppel-like factor 2 (KLF2) expression but decreased 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) expression in AML cells. KLF2 knockdown can counteract TRAF7-triggered PFKFB3 inhibition, and abolish TRAF7-mediated glycolysis inhibition and cell cycle arrest. KLF2 knockdown or PFKFB3 overexpression both can partially neutralize TRAF7-induced growth inhibition and apoptosis of K562 and Molm-13 cells. Moreover, Lv-TRAF7 decreased human CD45+ cells in mouse peripheral blood in the xenograft mice established by NOD/SCID mice. Taken together, TRAF7 exerts anti-leukemia effects by impairing glycolysis and cell cycle progression of myeloid leukemia cells via modulating the KLF2-PFKFB3 axis.
Subject(s)
Apoptosis , Leukemia, Myeloid, Acute , Humans , Animals , Mice , Cell Line, Tumor , Cell Proliferation/genetics , Mice, Inbred NOD , Mice, SCID , Apoptosis/genetics , Glycolysis/genetics , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/metabolism , Phosphoric Monoester Hydrolases/metabolism , Transcription Factors/metabolism , Tumor Necrosis Factor Receptor-Associated Peptides and Proteins/metabolism , Tumor Necrosis Factor Receptor-Associated Peptides and Proteins/pharmacology , Kruppel-Like Transcription Factors/genetics , Kruppel-Like Transcription Factors/metabolism , Kruppel-Like Transcription Factors/pharmacology , Phosphofructokinase-2/metabolism , Phosphofructokinase-2/pharmacologyABSTRACT
Nonhealing neuropathic foot ulcers remain a significant problem in individuals with diabetes. The gap-junctional protein connexin43 (Cx43) has roles in dermal wound healing and targeting Cx43 signalling accelerates wound reepithelialization. In a prospective, randomized, multicenter clinical trial we evaluated the efficacy and safety of a peptide mimetic of the C-terminus of Cx43, alpha connexin carboxy-terminal (ACT1), in accelerating the healing of chronic diabetic foot ulcers (DFUs) when incorporated into standard of care (SOC) protocols. Adults with DFUs of at least four weeks duration were randomized to receive SOC with or without topical application of ACT1. Primary outcome was mean percent ulcer reepithelialization and safety variables included incidence of treatment related adverse events (AEs) and detection of ACT1 immunogenicity. ACT1 treatment was associated with a significantly greater reduction in mean percent ulcer area from baseline to 12 weeks (72.1% vs. 57.1%; p = 0.03). Analysis of incidence and median time-to-complete-ulcer closure revealed that ACT1 treatment was associated with a greater percentage of participants that reached 100% ulcer reepitheliazation and a reduced median time-to-complete-ulcer closure. No AEs reported were treatment related, and ACT1 was not immunogenic. Treatment protocols that incorporate ACT1 may present a therapeutic strategy that safely augments the reepithelialization of chronic DFUs.