👤 Kiran Zahra

Melanocortin 4 receptor (MC4R) gene mutations are the most common cause of monogenic non-syndromic childhood obesity, but their relationship with asthma remains unclear. We report four cases of children with the same MC4R gene variant who presented with asthma in the setting of obesity. The asthma phenotype, severity, and presentation were variable between these patients. Some but not all also had comorbid obstructive sleep apnea (OSA) and evidence of metabolic abnormalities, including insulin resistance and hypertension. These findings suggest that the MC4R mutation and its associated morbid obesity are associated with asthma. Future studies are warranted to define the underlying pathobiology of asthma among children with MC4R mutations. Show less

Targeting the mitogen-activated protein kinase (MAPK) cascade in pancreatic ductal adenocarcinoma (PDAC) remains clinically unsuccessful. We aim to develop a MAPK inhibitor-based therapeutic combination with strong preclinical efficacy. Utilizing a reverse-phase protein array, we observe rapid phospho-activation of human epidermal growth factor receptor 2 (HER2) in PDAC cells upon pharmacological MAPK inhibition. Mechanistically, MAPK inhibitors lead to swift proteasomal degradation of dual-specificity phosphatase 6 (DUSP6). The carboxy terminus of HER2, containing a TEY motif also present in extracellular signal-regulated kinase 1/2 (ERK1/2), facilitates binding with DUSP6, enhancing its phosphatase activity to dephosphorylate HER2. In the presence of MAPK inhibitors, DUSP6 dissociates from the protective effect of the RING E3 ligase tripartite motif containing 21, resulting in its degradation. In PDAC patient-derived xenograft (PDX) models, combining ERK and HER inhibitors slows tumour growth and requires cytotoxic chemotherapy to achieve tumour regression. Alternatively, MAPK inhibitors with trastuzumab deruxtecan, an anti-HER2 antibody conjugated with cytotoxic chemotherapy, lead to sustained tumour regression in most tested PDXs without causing noticeable toxicity. Additionally, KRAS inhibitors also activate HER2, supporting testing the combination of KRAS inhibitors and trastuzumab deruxtecan in PDAC. This study identifies a rational and promising therapeutic combination for clinical testing in PDAC patients. Show less

Graves' disease (GD) is an autoimmune disease causing the overproduction of the thyroid hormone from thyroid gland. This disease is mainly the result of the production of antibodies against TSH receptors. Cytokines play an important role in orchestrating the pathophysiology in autoimmune thyroid disease. The regulatory role of IL-12 on TH1 cells has been proven. IL-27 and IL-35, members of IL-12 cytokine family, are two cytokines that have been newly discovered. IL-35 has been identified as a novel immunosuppressive and anti-inflammatory cytokine while IL-27 has both inflammatory and anti-inflammatory functions. The objective of the current study was to examine the changes in the serum level of the foregoing cytokines in GD patients in comparison to healthy controls. In this study, serum levels of IL-27 and IL-35 were determined by an ELISA method; anti TPO and anti Tg were measured by an RIA method in 40 new cases of Graves's disease. The findings were compared with 40 healthy controls. The results showed a significant difference between IL-27 and IL-35 regarding their serum levels with P values of 0.0001 and 0.024, respectively; anti TPO and anti Tg levels of the cases were also significantly different from controls (p < 0.001). The reduction in the serum levels of IL-27 and IL-35 in GD patients compared to normal subjects suggests the possible anti-inflammatory role of these cytokines in GD. Show less