Neoplastic lipogenesis is controlled through the modulation of the expression and maturation status of the transcription factor SREBP-1c, which stimulates fatty acid synthase transcription in normal and malignant cells. In tumor cells, SREBP-1c expression and maturation is constitutively driven by the aberrant hyperactivation of various pathways in response to a variety of oncogenic changes, including overproduction of growth factors (GFs), ligand-dependent or independent hyperactivation of GF receptors (GFRs), and loss of function of components of the signalling cascade such as the phosphatase and tensin homologue (PTEN).
MDA-MB-468 cells have an increased degree of epidermal growth factor receptor expression, these high levels of EGFR activity may be a reason behind the increased lipid content.
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