Improvements in the immunological, molecular, and genetic technologies such as next-generation sequencing have led to an exponential increase in the number of monogenic immune dysregulatory syndromes diagnosed, where type 1 diabetes (T1D) forms part of the autoimmune manifestations. Here, we reviewed the mutations in the signal transducer and activator of transcription (STAT) protein family, namely gain-of-function (GOF) mutations in STAT1 and STAT3 as well as STAT5b deficiency, that show strong association to T1D susceptibility. The equilibrium of T-helper 17 (Th17) and regulatory T cells (Tregs) is often found altered in patients affected by STAT GOF mutations. While the increased number of Th17 cells and the concomitant decrease in Treg cells may explain T1D in STAT3 GOF patients, the reduced number of Th17 cells found in those carrying STAT1 GOF mutations added a new level of complexity on the exact role of Th17 in the pathogenesis of T1D. Here, we describe the possible mechanisms through which STAT3 and STAT1 GOF mutations may perturb the fate and function of Th17 and Tregs and explore how this may lead to the development of T1D. We propose that the study of monogenic diseases, and in particular STAT mutations, may not only improve our understanding of the function of the human immune system but also shed light onto the pathogenic mechanisms of T1D and the genetic variants that confer predisposition to the disease.

Disturbances in the microbial ecosystem have been implemented in chronic inflammation, immune evasion and carcinogenesis, with certain microbes associated with the development of specific cancers. In recent times, the gut microbiome has been recognised as a potential novel player in the pathogenesis and treatment of malignant melanoma. It has been shown that the composition of gut microbiota in early‐stage melanoma changes from in situ to invasive and then to metastatic disease. The gut bacterial and fungal profile has also been found to be significantly different in melanoma patients compared to controls. Multiple studies of immune checkpoint inhibitor (ICI) therapies have shown that the commensal microbiota may have an impact on anti‐tumor immunity and therefore ICI response in cancer patients. When it comes to chemotherapy and radiotherapy treatments, studies demonstrate that gut microbiota are invaluable in the repair of radiation and chemotherapy‐induced damage and therapeutic manipulation of gut microbiota can be an effective strategy to deal with side effects. Studies demonstrate the oncogenic and tumor‐suppressive properties of the gut microbiome, which may play a role in the pathogenesis of melanoma. Despite this, investigations into specific interactions are still in its infancy, but starting to gain momentum as more significant and clinically relevant effects are emerging.

Objective Despite clear benefits in the management of children with Prader–Willi syndrome (PWS), the role of growth hormone (GH) in adults is unclear. The aim of this study was to conduct a systematic review to evaluate the effects of GH on body composition, bone health and cardiovascular health in adults with PWS. Design A systematic computerized literature search of the PubMed database was conducted by two independent reviewers. Inclusion criteria were individuals over the age of 16 years with a genetic diagnosis of PWS who had received GH therapy, together with assessment of body composition, bone health or cardiovascular health. Results Twenty full‐text papers met the inclusion criteria, encompassing 364 unique patients. No differences in body mass index (BMI) were noted, although 2 studies reported increased BMI after GH cessation. Data demonstrated statistically significant increases in lean body mass and reductions in percentage fat mass. Studies reported inconsistent effects of GH on cholesterol and echocardiography parameters. No studies reported differences in bone mineral density, although one reported improved bone geometry. Minor adverse events including pretibial oedema, headache and transient impaired glucose tolerance were reported in 7 studies. Conclusions These data suggest that GH is safe and well tolerated in adults with PWS, with evidence of improvement in body composition. Further longitudinal studies are still required to investigate the effects of GH on bone and cardiovascular health. Where GH is used in adults with PWS, this should be managed by a specialist multidisciplinary team with regular monitoring initiated.

The canonical NF-κB pathway regulates the transcription of many genes which may be involved in processes such as inflammation and proliferation, suggesting a potential link between the tumor, the tumor microenvironment and cancer-specific survival in colorectal cancer patients. Immunohistochemistry was used to assess the expression of the upstream kinase TAK1/pTAK1 and four members of the canonical NF-κB pathway in tissue microarrays. Protein expression was determined using the weighted histoscore method. BRaf status, tumor stroma percentage, local inflammation, systemic inflammation and cancer-specific survival were examined in patients with colorectal cancer. Cytoplasmic IKKβ was significantly associated with the inflammatory cell infiltrate (p=0.0015), systemic inflammation (p=0.03) and cancer-specific survival (p=0.046). In contrast, no significant association was found with the other three members. Cytoplasmic pTAK1 was associated with the tumor microenvironment (p=0.045) and cancer-specific survival (p=0.032). On multivariate analysis only cytoplasmic IKKβ associated with survival (HR1.75, 95%CI 1.05-291, p=0.033) and this was independent of TNM stage and markers of the tumor microenvironment. When cytoplasmic IKKβ was stratified with BRaf status (wild type (n=151) or mutant (n=48)), it was no longer associated with cancer-specific survival. However, when cytoplasmic pTAK1 was stratified with BRaf status its association with cancer-specific survival was strengthened. Cytoplasmic pTAK1 was significantly associated with cancer-specific survival in patients with wild type BRaf (p=0.014). In patients with BRaf mutations there was no significant association with cancer-specific survival (p=0.105), however the numbers were low and this is currently being investigated in a larger cohort. The results of the present study show that high expression of cytoplasmic IKKβ was associated with decreased cancer-specific survival and with markers of the tumor microenvironment in patients with colorectal cancer. Expression of cytoplasmic pTAK1 was associated with cancer-specific survival and this was enhanced in patients with tumors expressing wild type BRaf. Citation Format: Jean A. Quinn, Lindsay Bennett, Meera Patel, Lynette Loi, Mikaela Frixou, Antonia Roseweir, James H. Park, Paul G. Horgan, Donald C. McMillan, Joanne Edwards. The relationship between members of the canonical NF-κB pathway, components of the tumor microenvironment and cancer-specific survival in colorectal cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4070.