Primary adrenal insufficiency in a patient with biallelic QRSL1 mutations.

Background: Biallelic QRSL1 mutations cause mitochondrial 'combined oxidative phosphorylation deficiency-40' (COXPD40). COXPD40 has been reported to be invariably lethal in infancy. Adrenal insufficiency was weakly reported and investigated among seven previously reported patients with COXPD40. Objective: We report the clinical, biochemical, molecular, and functional characteristics of a patient with adrenal insufficiency due to COXPD40. Methods: The medical history and adrenal function tests were examined. Genetic analysis was performed using whole-exome sequencing. Mitochondrial function was tested using mitochondrial membrane potential (MMP) and superoxide dismutase (SOD) enzyme assays. Results: An 8-year-old boy was investigated for adrenal insufficiency. He also had mild developmental delay, sensorineural hearing loss, hypertrophic cardiomyopathy, nephrocalcinosis, elevated parathyroid hormone and creatine kinase, and lactic acidosis. Biallelic novel QRSL1 variants (c.300T>A;Y100* and c.610G>A;G204R) were identified. Oxidative damage in mitochondria was shown by reduced MMP and SOD assays in the patient compared to controls (P < 0.0001). Adrenal function tests revealed a 'primary adrenal insufficiency other than congenital adrenal hyperplasia' (non-CAH PAI) with an isolated glucocorticoid deficiency. In the 8-year follow-up, having the longest survival of reported COXPD40 patients, he had preserved mineralocorticoid functions and gonadal steroidogenesis. Conclusion: Biallelic QRSL1 mutations can cause non-CAH PAI. Adrenal functions should be monitored in mitochondrial disorders to improve clinical outcomes.

The role of HSP90 in Quercetin-induced apoptosis in human papillary thyroid (B-CPAP) cancer cells.

As in many other cancers, genetic alterations that occur in genes encoding for key proteins of major signalling pathways are the driving force for the tumorigenesis of thyroid cancer. HSP90 is an emerging therapeutic target of interest for the treatment of cancer and is responsible for modulating cellular response to stress by maintaining the function of signalling proteins. In this study, we have worked with B-CPAP, a thyroid papillary cancer cell line which is known to have BRAF V600E mutation. We have administered the flavonoid Quercetin, which is known to induce apoptosis by inhibiting HSP production on various cancer cell lines, at different concentrations (between 10 and 75µM) for 24hours. We have measured cell viability using WST-1 assay. We found that the viability decreases in a dose dependent manner. Then, we chose Quercetin concentrations between 10-75µM for 24hours, for the apoptosis and cell cycle analysis in flow cytometry by Annexin V and propidium iodide. We have also applied Hoechst stain to cancer cells for visualizing them on fluorescence microscopy and confirmed apoptosis with the presence of apoptotic signs in nuclei of cancer cells. Finally, we used Western blotting to compare HSP90 and Cleaved-PARP levels in cells treated with Quercetin and the control group. In the light of the obtained data, our results suggest that in future studies it would be useful to investigate the apoptotic mechanisms of Quercetin and use combinational therapies on BCPAP cells. Supported by Marmara University Scientific Research Commission (SAG-C-TUP-130313-0063).