The heat shock proteins family (HSP), so-called molecular chaperones, are involved in regulation of cellular proteostasis and stress management. Their major role is controlling proper protein folding, repair of misfolded proteins, transfer of newly-synthesized proteins through intracellular compartments and targeting damaged proteins for degradation to the proteasome system. HSPs are involved in multiple cellular processes through their ability to interact with many proteins, including co-chaperones. Under physiological conditions HSPs are directly or indirectly involved in signal transduction pathways, cell cycle regulation, proliferation, differentiation, apoptosis and cellular senescence. In addition, HSPs can be secreted in a variety of cells in a free form or in membrane-bound proteins. These so called extracellular HSPs have emerged as an important mediators of intercellular signalling and regulators of immune response. Constitutively expressed HSPs provide multiple housekeeping services in normal cells, however the level of numerous HSPs can be multiplied under endogenous and exogenous cellular stress conditions (environmental, pathophysiological conditions). Stress-induced accumulation of HSPs is considered as a potent cytoprotective factor.
Research conducted in our laboratory are aimed at studying the expression pattern, regulatory mechanism and functions of the genes encoding HSP proteins belonging to the human HSPA (HSP70) family. Specifically, we are interested in the major stress inducible HSPA1 protein and HSPA2, one of the least characterized member of the HSPA (HSP70) family. Expression and functions of the HSPA2 gene over the years has been associated with spermatogenesis and male fertility. However, we have revealed that HSPA2 is also expressed in selected populations of somatic cells, including epidermal keratinocytes and glial cells. We have found that in the human skin HSPA2 participates in regulation of epidermal keratinocyte differentiation process. It is also believed that HSPA2 is important cancer-related protein. HSPA2 is expressed in different types of human cancers and its high levels were correlated with unfavourable clinical outcome in patients. In vitro data indicates the role of HSPA2 protein in modulation of cancer cell phenotype.
elucidating the impact of the HSPA proteins on cancer cells phenotype, specifically on cell growth, invasive potential and chemoresistance; in our experiments we exploited non-small cell lung cancer and glioblastoma multiforme in vitro models;
examining the participation of HSPA proteins in regulating transcription factors activity (HIF-1, mutant p53 proteins);
examining the role of HSPA chaperone proteins and transcription factor HIF-1 in physiology and pathophysiology of the human epidermis.
Research techniques and methods:
mammalian cell culture in vitro: cell lines and primary cells;
isolation of primary epidermal and dermal cells and in vitro development of 3D cocultures for the study of keratinocyte differentiation and epidermis functions;
modulation of gene expression by using viral vectors;
DNA cloning, construction of the plasmid expression vectors coding for recombinant, modified and fusion proteins;
analysis of gene expression (RT-qPCR, RT-PCR, PCR arrays);
analysis of promoter activity by using the reporter gene assay;
analysis of protein level (Western blot, antibody arrays) and protein-protein interactions (co-IP, PLA);
analysis of drug cytotoxicity, cell death mechanisms, differentiation process, cellular aging, autophagy, cell adhesion and motility,
flow cytometry and sorting of specific cell populations defined by antigen expression;
histological techniques, immunohistochemistry, immunofluorescence;
light and fluorescence microscopy, including live cell imaging, and confocal microscopy.