多氨酸:影响瘤微环境的关键氨酸

Every normal cell or tissue is embedded in a complex local environment called stroma, consisting of different cell types, a basal membrane, and blood vessels. As normal cells mutate and develop into cancer cells, their local environment also changes to allow cancer progression. The tumor microenvironment (TME) consists of a complex cellular matrix of stromal cells and the developing tumor. The cross-talk between cancer cells and surrounding stromal cells is critical to disrupt normal tissue...

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the...

Microtubules are dynamic structures that undergo cycles of catastrophe and rescue. The microtubules play a central role in cell division by forming the spindle apparatus for segregating the chromosomes. This makes them ideal targets for regulating dividing cells in tumors and malignant cancer cells. Microtubule stabilizing drugs help stabilize the microtubule formation and promote its polymerization. Paclitaxel was the first microtubule stabilizing agent used as anticancer drug in chemotherapy...

Microtubules are dynamic structures and can be regulated by microtubule targeting agents (MTAs). Microtubule destabilizing drugs are a class of MTAs that destabilize and prevent microtubules' polymerization. Both natural and synthetic chemicals can be found under this class of drugs. Vincristine and vinblastine, two vinca alkaloids, and colchicine were among the first to be discovered. These drugs can affect cells in various ways, either by inducing a change in cell morphology, preventing...

The destabilization of microtubules can occur during different stages of the microtubule lifecycle, such as nucleation or elongation. It can take place at either end of the microtubule or in the microtubule lattices as a whole. The lifespan of individual microtubules within a cell varies according to the cell type and stage of the cell cycle. During interphase, the lifespan of the microtubule is about 30 minutes, while during cell division, it is about 15 minutes. In axonal microtubules of...

The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...