Cancer News

The New Mechanism of Aging To Promote Cancer

As we age, the body will accumulate “garbage” in the body during the process of converting food into energy. Clinical statistics have found that the risk of cancer and related mortality in humans increases significantly with age from the age of 65. Is it because the body’s “junk” substances accumulated due to age cause cancer? Recently, a study published in the journal Nature discovered a special metabolic pathway or plays a potential role in the process of cancer. This A research finding illustrates the mechanism by which the aging process accelerates the development of lethal cancer in individuals, and also provides a new treatment idea for effectively blocking the occurrence of metastatic tumors.

In this study, the researchers focused on cancer metastasis. The metastasis of cancer is the process by which cancer cells break away from the original tumor site and form new tumors at other sites in the body. Through observation and analysis of metastatic cancer cells, the researchers discovered some interesting phenomena, namely, the metabolites of methylmalonic acid (MMA), a byproduct of malonate metabolism, seem to accumulate as the body ages. And as a mediator of tumor progression. In order to analyze whether MMA plays a key role in the process of cancer metastasis, the researchers conducted related studies on people under 30 and over 60. When lung cancer cells and breast cancer cells are exposed to the blood of these people,  the behavior of lung and breast cancer cells whether change. The results of the study showed that in 30 blood samples from young donors, cancer cells in 25 samples did not show any changes, but in 30 blood samples from elderly donors, cancer cells in 25 samples exhibits different characteristics, its migration and invasion capabilities are enhanced, and it also has a certain tolerance to two drugs that are often used to treat cancer.

Figure 1. The relation of MMA and Sox4.

More interestingly, when the treated cancer cells are injected into mice, they will produce metastatic tumors in the lung tissues of the mice. So does MMA induce these changes in cancer cells? Through experimental research, it is found that the key to the changes in cancer cells induced by MMA seems to be the existence of a special reprogramming mechanism, which turns on the expression of the SOX4 gene. Previous studies have shown that SOX4 can make cancer cells more aggressive and easier to metastasize.

To determine the correlation between MMA and SOX4, the researchers blocked the expression of this gene. It was found that after blocking the Sox4 gene, the induction effect of MMA could not be produced. In addition, blocking the function of SOX4 also inhibits the ability of cancer cells to develop resistance to the two cancer therapies. This provides new ideas for new therapies to reduce mortality in cancer populations by descreasing MMA levels.

At present, researchers still have a series of questions to be solved, including why MMA will continue to accumulate in the body as the body ages, and whether the mechanisms found in blood samples and mouse studies are the same in humans. In addition, the blood samples used in the existing research are all from men, and it is necessary to verify whether the same mechanism will also appear in the female body in the later period.

Existing studies have shown that the accumulation of MMA is related to the intake of a high-protein diet, so a low-protein diet may be helpful in the treatment of cancer patients. Theoretically, drugs that lower MMA levels may also work, that is, potentially reducing the malignant spread of cancer in the patient’s body.