Invited lecture at Molecular interactions: minisymposium 2018, nov 2018, Ljubljana, Slovenia
B.04 Guest lecture
COBISS.SI-ID: 31874343In modern medicine many drugs and therapeutic approaches are available for the treatment of cancer. However, the disease often develops into an invasive metastatic form or recurs after years of remission. This may be attributed to cancer stem cells (CSCs), a small subset of cells with a tumorigenic potential that is resistant to most of therapeutic approaches. Thus, new therapeutic approaches effective, not only towards differentiated cancer cells, but also CSCs, are required. Lysosomal cysteine peptidases, cathepsin B and X that have important role in different processes of development and progression of cancer, could serve as promising molecular targets to improve CSCs-directed therapy. First, we isolated cancer stem cells from three breast cancer cell lines MDA-MB-231, MCF7 and MCF-10A neoT, based on their ability to form tumorspheres, a characteristic that distinguishes CSCs from differentiated cells. For this purpose, we first determined the optimal conditions for tumorsphere formation. The most optimal medium for tumorsphere formation was DMEM/F-12 with serum free supplement for CSC growth B-27, and growth factors EGF and bFGF. Additionally, insulin and hydrocortisone were added for growth of MCF-10A neoT cells. Isolation of CSCs was confirmed by expression of cell surface markers and stem cell transcription factor SOX2. Following tumorsphere formation surface markers (CD44+/CD24%) and/or increased expression of SOX2 showed increase in cells with CSC phenotype. Next,...
D.10 Educational activities
COBISS.SI-ID: 4885617Cathepsin V is a lysosomal cysteine peptidase, a member of the papain-like cysteine peptidase family. It is closely related to cathepsin L; however, like cathepsin L it is not ubiquitously expressed while its physiological expression is manly limited to thymus, testis, and corneal epithelium. In pathological processes, it is expressed also in other tissues. It contributes to cancer progression, where its increased expression was observed in colorectal and breast carcinomas, but not in the normal colon or mammary tissue. In addition, cathepsin V plays an important role in immune cells and in antitumor immune response, where it is involved in the activation of cystatin F, which impairs the function of cytotoxic cells. Due to its involvement in cancer progression, targeting this enzyme with selective inhibitors may open new possibilities for improvements in cancer immunotherapy. For this purpose, we tested compounds obtained from virtual chemical libraries, by their molecular docking into the active site of cathepsin V. Their inhibition of cathepsin V activity and selectivity for cathepsin V compared to cathepsin L was evaluated by using enzyme kinetics and microscale thermophoresis. Compounds 7, 26, and 28 were identified as the most potent inhibitors of cathepsin V. Compounds 7 and 28 are selective inhibitors of cathepsin V while compound 26 is a non-selective inhibitor. Best performing compounds were further tested for their effect on cell viability to determine...
D.10 Educational activities
COBISS.SI-ID: 21019395