Fig. 3

Potential mechanisms contributing to increased cholesterol availability for cancer cells. PCSK9 is closely associated with the incidence and progression of several cancers. In several studies, PCSK9 siRNA was shown to effectively suppress the proliferation and invasion of several studied tumor cells. Cancer cell’s demand for cholesterol is supplied by both uptake from the blood or de novo synthesis. Therefore, high plasma cholesterol may provide such a high cancer cell requirement. On the other hand, oxidized cholesterol derivatives, namely oxysterols, show a significant apoptotic effect, thus opposing cancer cell proliferation [45]