Cell and Molecular Biology of Cancer Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA.
Subcell Biochem. 2022;98:15-40. doi: 10.1007/978-3-030-94004-1_2.
Macropinocytosis is an evolutionarily conserved endocytic pathway that mediates the nonselective acquisition of extracellular material via large endocytic vesicles known as macropinosomes. In addition to other functions, this uptake pathway supports cancer cell metabolism through the uptake of nutrients. Cells harboring oncogene or tumor suppressor mutations are known to display heightened macropinocytosis, which confers to the cancer cells the ability to survive and proliferate despite the nutrient-scarce conditions of the tumor microenvironment. Thus, macropinocytosis is associated with cancer malignancy. Macropinocytic uptake can be induced in cancer cells by different stress stimuli, acting as an adaptive mechanism for the cells to resist stresses in the tumor milieu. Here, we review the cellular stresses that are known to promote macropinocytosis, as well as the underlying molecular mechanisms that drive this process.
巨胞饮作用是一种进化上保守的内吞途径，通过称为巨吞饮泡的大内吞泡介导细胞对细胞外物质的非选择性摄取。除了其他功能外，这种摄取途径还通过摄取营养物质来支持癌细胞代谢。已知携带癌基因或肿瘤抑制基因突变的细胞会表现出更高的巨胞饮作用，这使癌细胞能够在肿瘤微环境中营养匮乏的情况下存活和增殖。因此，巨胞饮作用与癌症的恶性程度有关。不同的应激刺激可以诱导癌细胞发生巨胞饮作用，这是癌细胞在肿瘤微环境中抵抗应激的一种适应性机制。在这里，我们综述了已知促进巨胞饮作用的细胞应激，以及驱动这一过程的潜在分子机制。
