Unravel the functions of autophagy in breast cancer motility Group Tschan Metastasis formation accounts for the majority of deaths from breast cancer, making it imperative to better understand the mechanisms driving the metastatic cascade in order to develop therapeutic interventions to target it. We earlier discovered an oncogenic splice variant of a transcription factor and named it DMTF1β. We now show that DMTF1β promotes invasion and tumor-initiating capacity of breast cancer cells by activating autophagy. It has also been shown that inhibition of autophagy can have undesirable effects in some cancer types and induce epithelial to mesenchymal transition (EMT), one of the early steps of metastasis. Our aim is to identify cellular conditions in which autophagy inhibition will decrease migration, and those in which the inhibition of autophagy will promote invasiveness. Cancer-associated fibroblast from breast cancer patient
PU.1 and alternative splicing Group Tschan The transcription factor PU.1 (SPI1) plays a key role in myeloid differentiation as well as in myeloid cell survival. Aberrant low PU.1 expression contributes to an immature myeloid phenotype, e.g., acute myeloid leukemia (AML). Interestingly, two studies indicate that high PU.1 protein levels were associated with alternative splicing promoted by either direct binding to splice factors or by mRNA binding. Our data indicate that PU.1 controls splicing of the anti-apoptotic CFLAR (cFLIP) gene, and thereby regulates cell death during myeloid differentiation. Schematic representation of how PU.1 might regulate splicing of the anti-apoptotic gene CFLAR
Reducing FASN expression facilitates AML differentiation Group Tschan Apart from glycolysis and OXPHOS, lipid metabolism is frequently reprogrammed in leukemic cells to support cellular growth. Particularly, the protein important for de novo lipid synthesis, fatty acid synthase (FASN), is frequently upregulated in tumor cells. We found that high FASN expression in acute myeloid leukemia (AML) cells is associated with an immature hematopoietic phenotype. Decreasing FASN levels by RNAi or epigallocatechin-3-gallate (EGCG) treatment, but no blocking its enzymatic function, resulted in improved response of AML cells to differentiation therapy. FASN localizes at the lysosome (LAMP1) to increase mTOR activity. NB4 APL cells were differentiated towards neutrophils with all-trans retinoid acid (ATRA)
