Action Myoclonus-Renal Failure Syndrome: A Case Report with Bioinformatic Annotations.

Action myoclonus-renal failure (AMRF) syndrome is a rare autosomal recessive disorder characterized by myoclonic epilepsy with occasional renal failure comorbidity. This study examines a consanguineous family with multiple members presenting myoclonic epilepsy. The disease's continued transmission within the family is attributable to a lack of genetic testing and the inability to establish a definitive diagnosis. Our objective is to guide physicians toward accurate diagnoses and reduce the disease's recurrence through appropriate genetic counseling. Various diagnostic approaches can contribute to identifying AMRF. While magnetic resonance imaging (MRI) results and blood panels may not yield definitive diagnoses, electromyography (EMG) studies can serve as a robust diagnostic tool, leading to genetic confirmation. In line with standardized protocols, EMG findings consistent with AMRF present a polyneuropathy characterized by axonal degeneration and demyelinating features. These features manifest as decreased amplitude for axonal degeneration and decreased nerve conduction velocity (NCV) for demyelination. The presence of such EMG findings in a patient exhibiting both renal and central nervous system involvement may reinforce a preliminary diagnosis and warrant further genetic analysis.

Proteomic identification of putative biomarkers of radiotherapy resistance: a possible role for the 26S proteasome?

PURPOSE: We aimed to identify putative predictive protein biomarkers of radioresistance. EXPERIMENTAL DESIGN: Three breast cancer cell lines (MCF7, MDA-MB-231, and T47D) were used as in vitro models to study radioresistance. Inherent radiosensitivities were examined using a clonogenic survival assay. It was revealed that each cell line differed in their response to radiotherapy. These parental breast cancer cell lines were used to establish novel derivatives (MCF7RR, MDA-MB-231RR, and T47DRR) displaying significant resistance to ionizing radiation. Derivative cells were compared with parental cells to identify putative biomarkers associated with the radioresistant phenotype. To identify these biomarkers, complementary proteomic screening approaches were exploited encompassing two-dimensional gel electrophoresis in combination with mass spectrometry, liquid chromatography coupled with tandem mass spectrometry and quantitative proteomics using iTRAQ technology. RESULTS: A large number of potential biomarkers were identified, and several of these were confirmed using Western blot analysis. In particular, a decrease in the expression of the 26S proteasome was found in all radioresistant derivatives when compared with the respective parent cells. Decreased expression of this target was also found to be associated with radioresistant laryngeal tumors (P = .05) in a small pilot immunohistochemical study. CONCLUSIONS: These findings suggest that the 26S proteasome may provide a general predictive biomarker for radiotherapy outcome.