Targeting allosteric site of AKT by 5,7-dimethoxy-1,4-phenanthrenequinone suppresses neutrophilic inflammation.

BACKGROUND: Acute lung injury (ALI) is a severe life-threatening inflammatory disease. Neutrophil activation is a major pathogenic factor in ALI. Protein kinase B (PKB)/AKT regulates diverse cellular responses, but the significance in neutrophilic inflammation and ALI remains unknown. METHODS: Human neutrophils and neutrophil-like differentiated HL-60 (dHL-60) cells were used to examine the anti-inflammatory effects of 5,7-dimethoxy-1,4-phenanthrenequinone (CLLV-1). The therapeutic potential of CLLV-1 was determined in a mouse model of lipopolysaccharide (LPS)-induced ALI. FINDINGS: CLLV-1 inhibited respiratory burst, degranulation, adhesion, and chemotaxis in human neutrophils and dHL-60 cells. CLLV-1 inhibited the phosphorylation of AKT (Thr308 and Ser473), but not of ERK, JNK, or p38. Furthermore, CLLV-1 blocked AKT activity and covalently reacted with AKT Cys310 in vitro. The AKT309-313 peptide-CLLV-1 adducts were determined by NMR or mass spectrometry assay. The alkylation agent-conjugated AKT (reduced form) level was also inhibited by CLLV-1. Significantly, CLLV-1 ameliorated LPS-induced ALI, neutrophil infiltration, and AKT activation in mice. INTERPRETATION: Our results identify CLLV-1 as a covalent allosteric AKT inhibitor by targeting AKT Cys310. CLLV-1 shows potent anti-inflammatory activity in human neutrophils and LPS-induced mouse ALI. Our findings provide a mechanistic framework for redox modification of AKT that may serve as a novel pharmacological target to alleviate neutrophilic inflammation.

The rs1447295 at 8q24 is a risk variant for prostate cancer in Taiwanese men.

OBJECTIVES: To determine the association of a common variant, rs1447295, at the 8q24 region with prostate cancer (PCa) risk in Taiwanese men. Common variants at the 8q24 region have been shown to be associated with PCa risk. The variant rs1447295 has shown the strongest association. Most of the studies have been performed in European and American populations. METHODS: This case-control study comprised 340 PCa patients and 337 controls. Genotyping was performed for rs14417295 to test for the association between its risk allele and PCa. Its association with disease stage, Gleason score, PSA level, and disease aggressiveness was also determined. RESULTS: The A allele of rs1447295 was significantly associated with increased PCa risk (odds ratio = 1.49, 95% CI = 1.12-1.99). When compared with controls, the risk allele A was more frequent in PCa patients of both stages I+II (P = .028) and stages III+IV (P = .023), in patients of all Gleason scores (P < .05 in all subgroups), in patients with PSA levels >20 ng/mL (P = .001), and in patients with aggressive disease (P = .005). CONCLUSIONS: This study confirmed that the A allele of rs1447295 is associated with a high risk of PCa in Taiwanese men.