Mutational screening of GDAP1 in dysphonia associated with Charcot-Marie-Tooth disease: clinical insights and phenotypic effects.

INTRODUCTION: Mutations in GDAP1 (Ganglioside-induced differentiation-associated protein 1) gene are linked to Charcot-Marie-Tooth disease (CMT), a Heterogenous group of disorders with multiple phenotypes, characterized by peripheral nerve dysfunction that can lead to vocal cord paralysis and diaphragmatic dysfunction. MAIN BODY: All three affected children of this chosen family have manifested the same clinical symptoms with progressive weakness, mild sensory impairment, and absent tendon reflexes in their early years. Electrodiagnostic analysis displayed an axonal type of neuropathy in affected patients. Sequencing of the GDAP1 gene was requested for all members of the family. Diagnostic assessments included pulmonary and vocal cord function tests, as well as phrenic and peripheral nerve conduction studies. Pathogenicity of GDAP1 variant p.Pro419Leu with axonal CMT2 and autosomal recessive inheritance was confirmed via in silico analysis. Patients with GDAP1 mutations showed dysphonia, speech difficulties, and the characteristic symptoms of CMT. The severity of symptoms correlated with the presence of a type of GDAP1 mutation. Patients with normal vocal cords and pulmonary function exhibited milder symptoms compared to those with GDAP1 mutations. Our study provides clinical insights into the phenotypic effects of GDAP1 mutations in CMT patients. The findings highlight the adverse clinical course and severe disability associated with GDAP1 mutations, including weak limb and laryngeal muscles. CONCLUSION: Patients with GDAP1 mutations and autosomal recessive neuropathy present with dysphonia and require interventions such as surgery, braces, physical therapy, and exercise. Early diagnosis and comprehensive clinical evaluations are crucial for managing CMT patients with GDAP1 mutations.

Circulating MiRNA-373 as a Predictor of Response to Super-selective Transarterial Chemoembolization Bridging Therapy in Hepatocellular Carcinoma Patients Awaiting Liver Transplantation.

BACKGROUND: Super selective transarterial chemoembolization (TACE) has emerged as a bridging therapy for early hepatocellular carcinoma (HCC) patients awaiting liver transplantation. This study aimed at assessing the expression profiles of circulating MiR-210 and MiR-373 as potential predictors of response to TACE bridging therapy in a group of Egyptian HCC cases on top of chronic hepatitis-C infection, awaiting liver transplantation. METHODS: Fifty-three HCC cases awaiting liver transplantation referred for TACE, were followed up for three months, resulting in forty-five responders and eight non-responders based on modified response evaluation criteria in solid tumors (mRECIST). Circulating pre TACE MiR-210 and MiR-373 expressions were determined using reverse transcription quantitative polymerase chain reaction. RESULTS: Circulating pre TACE MiR-373, but not MiR-210, was significantly higher in non-responders than responders. Receiver operating characteristics (ROC) curve analysis of MiR-373, pre-TACE tumor volume, inflammatory score, and albumin bilirubin (ALBI) grade revealed highest sensitivity for pre-TACE tumor volume (cutoff>11.49 cm3) and highest specificity for pre-TACE MiR-373 (cutoff>1.46-fold change). Multivariate logistic regression revealed pre TACE MiR-373 as a significant independent predictor of TACE response after adjusting for pre TACE tumor volume. CONCLUSION: Circulating pre-TACE MiR-373 could assist as a noninvasive predictor marker of response to TACE bridging therapy in early HCC patients awaiting liver transplantation.

Comparison of multiple gene expression platforms for measuring a bladder cancer hypoxia signature.

Tumour hypoxia status provides prognostic information and predicts response to hypoxia­modifying treatments. A previous study by our group derived a 24­gene signature to assess hypoxia in bladder cancer. The objectives of the present study were to compare platforms for generating signature scores, identify cut­off values for prospective studies, assess intra­tumour heterogeneity and confirm hypoxia relevance. Briefly, RNA was extracted from prospectively collected diagnostic biopsies of muscle invasive bladder cancer (51 patients), and gene expression was measured using customised Taqman Low Density Array (TLDA) cards, NanoString and Clariom S arrays. Cross­platform transferability of the gene signature was assessed using regression and concordance analysis. The cut­off values were the cohort median expression values. Intra­ and inter­tumour variability were determined in a retrospective patient cohort (n=51) with multiple blocks (2­18) from the same tumour. To demonstrate relevance, bladder cancer cell lines were exposed to hypoxia (0.1% oxygen, 24 h), and extracted RNA was run on custom TLDA cards. Hypoxia scores (HS) values showed good agreement between platforms: Clariom S vs. TLDA (r=0.72, P<0.0001; concordance 73%); Clariom S vs. NanoString (r=0.84, P<0.0001; 78%); TLDA vs. NanoString (r=0.80, P<0.0001; 78%). Cut­off values were 0.047 (TLDA), 7.328 (NanoString) and 6.667 (Clariom S). Intra­tumour heterogeneity in gene expression and HS (coefficient of variation 3.9%) was less than inter­tumour (7.9%) variability. HS values were higher in bladder cancer cells exposed to hypoxia compared with normoxia (P<0.02). In conclusion, the present study revealed that application of the 24­gene bladder cancer hypoxia signature was platform agnostic, cut­off values determined prospectively can be used in a clinical trial, intra­tumour heterogeneity was low and the signature was sensitive to changes in oxygen levels in vitro.

Selection of endogenous control genes for normalising gene expression data derived from formalin-fixed paraffin-embedded tumour tissue.

Quantitative real time polymerase chain reaction (qPCR) data are normalised using endogenous control genes. We aimed to: (1) demonstrate a pathway to identify endogenous control genes for qPCR analysis of formalin-fixed paraffin-embedded (FFPE) tissue using bladder cancer as an exemplar; and (2) examine the influence of probe length and sample age on PCR amplification and co-expression of candidate genes on apparent expression stability. RNA was extracted from prospective and retrospective samples and subject to qPCR using TaqMan human endogenous control arrays or single tube assays. Gene stability ranking was assessed using coefficient of variation (CoV), GeNorm and NormFinder. Co-expressed genes were identified from The Cancer Genome Atlas (TCGA) using the on-line gene regression analysis tool GRACE. Cycle threshold (Ct) values were lower for prospective (19.49 ± 2.53) vs retrospective (23.8 ± 3.32) tissues (p < 0.001) and shorter vs longer probes. Co-expressed genes ranked as the most stable genes in the TCGA cohort by GeNorm when analysed together but ranked lower when analysed individually omitting co-expressed genes indicating bias. Stability values were < 1.5 for the 20 candidate genes in the prospective cohort. As they consistently ranked in the top ten by CoV, GeNorm and Normfinder, UBC, RPLP0, HMBS, GUSB, and TBP are the most suitable endogenous control genes for bladder cancer qPCR.

Comparison between Sigma metrics in four accredited Egyptian medical laboratories in some biochemical tests: an initiative towards sigma calculation harmonization.

INTRODUCTION: Analytical quality is an essential requirement for best practice in any medical laboratory. Lack of a harmonized approach for sigma calculation is considered an obstacle in the objective comparability of analytical performance among laboratories adopting sigma metrics. It is urgently needed that all laboratory professionals interested in the analytical quality to work hard towards harmonization protocol for sigma calculation in order to properly select their analytical goals. This study aims at harmonization of Sigma metrics calculation in four accredited Egyptian laboratories. MATERIALS AND METHODS: This observational cross sectional study compared the sigma levels for certain biochemical parameters in the four participating laboratories. RESULTS: Coefficient of variation (CV) and bias were determined for some biochemical analytes, data assayed by different automated analysers in the four different accredited laboratories. The sigma level for the four medical laboratories was calculated for each biomedical parameter with changed sigma level after total allowable error (Tea) unification among participating laboratories. CONCLUSION: Each laboratory should select the TEa goal based on clear standardized criteria of selection without any subjective preferences as either under or over estimation of Sigma metrics will affect the patient centred care negatively if laboratories use quality control procedures wrongly based on incorrect Sigma metrics calculation with subsequent misleading medical decisions.