A woman developed 12 tumors (7 benign and 5 cancerous) before her 40th birthday. Medical researchers recently discovered why she is prone to abnormal growth. She has a series of genetic mutations never before seen in humans.
The now 36-year-old woman has two mutated copies of a gene called MAD1L1, one from each parent, according to a new report published in the journal on Wednesday (November 2). scientific progress (opens in new tab)This gene encodes a protein called MAD1 that plays an important role in cell division.
When one cell is split into two, all cells are duplicated first. DNA The genetic material is then packaged into compact structures called chromosomes. The chromosomes are then neatly aligned along the midline of the cell and pulled in half. That way, when the mother cell splits into her two, half of the DNA ends up in each daughter cell. The MAD1 protein helps the chromosomes align correctly during this process, so all cells end up with the normal 23 pairs of chromosomes. Uniplot (opens in new tab)a database of protein sequences and functional information.
When laboratory mice carry two mutated copies of MAD1L1, rodents die in utero. But for the female, although she survived into adulthood, she was highly susceptible to tumors throughout her life: she developed her first cancerous tumor at the age of 2, and had a recent cancer at age 28. developed a sexually transmitted tumor.
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“It was very difficult to understand how this woman could survive with this mutation. Marcos Marmbres (opens in new tab)The head of the cell division and cancer group at the Spanish National Cancer Research Center (CNIO) in Madrid told a Spanish newspaper. El Pais (opens in new tab)“There must have been something else that helped her escape.” [death]said Marmbres, according to Live Science’s translation.
Analysis of the patient’s blood revealed that approximately 30% to 40% of the circulating blood cells had an abnormal number of chromosomes.
Other genetic mutations besides those affecting MAD1L1 can cause people to have cells with different numbers of chromosomes. In some, but not all, patients, this appears to increase the risk of cancer, the researchers wrote in their report. or have missing cells. National Cancer Institute (opens in new tab)however, scientists are investigating exactly how this genetic trait contributes to the growth and spread of cancer.
Despite having had cancer five times, the patient was treated relatively easily each time she developed the disease. No symptoms. Medical researchers believe this may be due to her unique immune system.
In their analysis, they found that the presence of cells with an abnormal number of chromosomes initiates a protective immune response in cells with the typical 23 pairs.These immune cells drive inflammation These cells spread throughout a woman’s body and release specific molecules and inflammatory substances that help the immune system find and destroy cancerous tumors. , may explain why they responded so well to cancer treatments such as surgery, the team theorizes.
“The constant production of altered cells creates a chronic protective response in patients against these cells that helps the tumor disappear,” Malumbres said. statement (opens in new tab)The team hopes to further study immune defenses in women and see if they can be replicated in other cancer patients.
“We believe that boosting the immune response in other patients can help stop tumors from developing,” Malumbres said. At least conceptually, such treatments resemble existing immunotherapies designed to boost the immune system’s ability to target and kill cancer cells.
