Citrullination of glucokinase is linked to autoimmune diabetes.

Inflammation, including reactive oxygen species and inflammatory cytokines in tissues amplify various post-translational modifications of self-proteins. A number of post-translational modifications have been identified as autoimmune biomarkers in the initiation and progression of Type 1 diabetes. Here we show the citrullination of pancreatic glucokinase as a result of inflammation, triggering autoimmunity and affecting glucokinase biological functions. Glucokinase is expressed in hepatocytes to regulate glycogen synthesis, and in pancreatic beta cells as a glucose sensor to initiate glycolysis and insulin signaling. We identify autoantibodies and autoreactive CD4+ T cells to glucokinase epitopes in the circulation of Type 1 diabetes patients and NOD mice. Finally, citrullination alters glucokinase biologic activity and suppresses glucose-stimulated insulin secretion. Our study define glucokinase as a Type 1 diabetes biomarker, providing new insights of how inflammation drives post-translational modifications to create both neoautoantigens and affect beta cell metabolism.

Src family kinases, HCK and FGR, associate with local inflammation and tumour progression in colorectal cancer.

BACKGROUND: In colorectal cancer (CRC), inflammatory responses have been reported to associate with patient survival. However, the specific signalling pathways responsible for regulating inflammatory responses are not clear. Src family kinases (SFKs) impact tumourigenic processes, including inflammation. METHODS: The relationship between SFK expression, inflammatory responses and cancer specific survival (CSS) in stage I-III CRC patients was assessed using immunohistochemistry on a 272 patient discovery cohort and an extended 822 patient validation cohort. RESULTS: In the discovery cohort, cytoplasmic FGR associated with improved CSS (P = 0.019), with membrane HCK (p = 0.093) trending towards poorer CSS. In the validation cohort membrane FGR (p = 0.016), membrane HCK (p = 0.019), and cytoplasmic HCK (p = 0.030) all associated with poorer CSS. Both markers also associated with decreased proliferation and cytotoxic T-lymphocytes (all p < 0.05). Furthermore, cytoplasmic HCK was an independent prognostic marker compared to common clinical factors. To assess synergy a combine FGR + HCK score was assessed. The membrane FGR + HCK score strengthened associations with poor prognosis (p = 0.006), decreased proliferation (p < 0.001) and cytotoxic T-lymphocytes (p < 0.001). CONCLUSIONS: SFKs associate with prognosis and the local inflammatory response in patients with stage I-III CRC. Active membrane FGR and HCK work in parallel to promote tumour progression and down-regulation of the local inflammatory lymphocytic response.