How Do Cancer Cells Absorb Nutrients? How Does It Destroy Normal Cells?

Cancer cells are quite different from normal cells in terms of morphology, structure, metabolic characteristics and growth mode, which are as follows:

(1) Different morphology and structure Under normal conditions, the size and shape of cells from the same tissue are basically the same. Cancer cells are generally larger than the corresponding normal cells, and the size and shape of cancer cells are also very different from each other, and sometimes large "tumor giant cells" appear. All cells contain a nucleus and cytoplasm. Normally, most cells have only one nuclear industry and a certain ratio of nuclei to cytoplasm. The size of the cell nucleus in the fine breast of cancer increased, and the shape was inconsistent, and megakaryons, double nuclei, multiple nuclei or irregular nuclei could appear. The quality and quantity of the cytoplasm of cancer cells were also different from that of normal cells.

(2) Cell metabolism is different. Any living cell must carry out metabolism (including the metabolism of proteins, sugars, enzymes and genetic material nucleic acids) to maintain cell life. Cancer cells are also living cells, and their metabolic characteristics are very different from those of normal tissue cells. The synthesis of substances that constitute the basic structure of cells, such as proteins and nucleic acids, is extremely vigorous. On the contrary, the catabolism is significantly reduced, so that the balance between synthesis and catabolism is unbalanced. Increased metabolism of cancer cells is also one of the reasons why cancer is harmful to the human body. For example, the protein metabolism of cancer tissue is vigorous, especially the protein synthesis is greatly enhanced, and even the protein decomposition products of normal tissue are taken away to synthesize the protein needed by cancer tissue itself. As a result, cancer patients are in a state of severe consumption cachexia.

Compared with normal cells, the growth of cancer cells has two characteristics. The first is the autonomy with which cancer cells grow. When cultured cells are found, normal cells stop dividing when they come into contact with surrounding cells during the process of division and reproduction. This phenomenon is called "contact inhibition" of cell proliferation, which can inhibit the excessive proliferation of cells. Cancer cells, to varying degrees out of the control of the body, are often manifested as uninterrupted growth, reproduction and poor differentiation, which is called the "autonomous growth" or "autonomous growth" of cancer cells. As cancer progresses, "autonomy" always increases, and the faster it grows, the faster it develops. The second characteristic of cancer cell growth is invasion and metastasis. This is the main distinguishing feature between benign and malignant tumors. Only malignant tumors have invasion and metastasis. Due to the adhesion between normal cells, the diffusion of cells to nearby and distant areas is limited. However, a series of changes can occur on the surface of cancer cells to reduce the adhesion between cells, so that cancer cells are easy to fall off, dissolve and invade the surrounding tissues, or invade the blood and lymphatic tissues, and spread to other parts of the body through the circulation of blood and lymph fluid, resulting in the spread and metastasis of cancer.

(4) The inheritance of cellular characteristics Cancer cells can pass on their autonomy, invasion and metastasis characteristics to their offspring cells, so that newly propagated cancer cells have the same characteristics, so the cancer can continue to expand and even spread widely, and maintain the malignant characteristics of cancer cells forever.