Search Results
Proteomic insights into non-small cell lung cancer: New ideas for cancer diagnosis and therapy from a functional viewpoint
We recently characterized SEC62 as an oncogene in non-small-cell lung cancer (NSCLC). Here we aimed to gain further insight into the molecular mechanisms of the cancer-related functions of this oncogene. We performed 2D-DIGE proteome analysis of tumor material from patients with NSCLC and of HEK293 cells stably overexpressing plasmid-encoded SEC62, combined with investigation of the Sec62 interactome. Furthermore, we analyzed the proteomic effects of siRNA-mediated depletion of the Sec62-interacting protein Sec63. We identified a comprehensive list of differentially regulated proteins, providing new insights into the molecular mechanisms of the cancer-related functions of Sec62 in cell migration, drug resistance, and Ca2+-homeostasis.
The Caveolin-3 G56S sequence variant of unknown significance: Muscle biopsy findings and functional cell biological analysis
Purpose: In the era of next-generation sequencing, we are increasingly confronted with se- quence variants of unknown significance. This phenomenon is also known for variations in Caveolin-3 and can complicate the molecular diagnosis of the disease. Here, we aimed to study the ambiguous character of the G56S Caveolin-3 variant. Experimental design: A comprehensive approach combining genetic and morphological stud- ies of muscle derived from carriers of the G56S Caveolin-3 variant were carried out and linked to biochemical assays (including phosphoblot studies and proteome profiling) and morphological investigations of cultured myoblasts. Results: Muscles showed moderate chronic myopathic changes in all carriers of the variant. Myogenic RCMH cells expressing the G56S Caveolin-3 protein presented irregular Caveolin-3 deposits within the Golgi in addition to a regular localization of the protein to the plasma mem- brane. This result was associated with abnormal findings on the ultra-structural level. Phos- phoblot studies revealed that G56S affects EGFR-signaling. Proteomic profiling demonstrated alterations in levels of physiologically relevant proteins which are indicative for antagonization of G56S Caveolin-3 expression. Remarkably, some proteomic alterations were enhanced by osmotic/mechanical stress. Conclusions and clinical relevance: Our studies suggest that G56S might influence the mani- festation of myopathic changes upon the presence of additional cellular stress burden. Results of our studies moreover improve the current understanding of (genetic) causes of myopathic disorders classified as caveolinopathies.