Tuesday , July 27 2021

DNA repair to cure cancer and malformations



Report. In the last decade, biomedical scientists from universities, institutes and private laboratories have developed different techniques that seek to correct errors and damages suffered by DNA molecules when they are copied. In 2018, Mexico was the first country in the world to approve the use of & # 39; & # 39 new type; therapy called "medicine & # 39; precision" against cancer & # 39; white blood cell type Leukemia Chronic lymphocytic

DNA or deoxyribonucleic acid is a molecule found in the nucleus of & # 39; any cell & # 39; live humans, animals or plants. Every time a cell is copied and to reproduce before dying, DNA is copied into the original cell and be moved into the new cell. But when there are errors in copying can & # 39; serious illness and even fatal such as different kinds & # 39; cancer.

In the last decade, biomedical scientists from universities, institutes and private laboratories have developed different techniques that seek to correct errors and damages suffered by DNA molecules when they are copied.

We must remember that the DNA molecule is similar to two long threads connected by links, making them look like a staircase & # 39; & # 39 by painter; thousands & # 39; steps. When a bank or break step when they step in it & # 39; a different order from the original – what is known as translocation – problems arise. Using & # 39; analogy, we can say that DNA is a long wall of the golf club but thinner than hair and each cell has the same one in its nucleus.

Today, b & # 39; work at a & # 39; molecules has opened a new area & # 39; pharmacology called High Precision Medicine, which has already generated medicines available in hospitals in & # 39; different parts of the world, including Mexico, to stop the multiplication of & # 39; cancer cells in the blood and lungs, among other textiles.

Another new technique of DNA repair, you can & # 39; regarded as "revolutionary", without esiġerazzjoni, is editing & # 39; genes through & # 39; biochemical scissors called CRISPR-Cas9, already used in & # 39; laboratories in China, the United States and Korea, to repair damage in the genome that causes lung cancer and malformations of -qalb f & # 39; human embryos. That technique is not yet commercially available, but its tests are advancing rapidly.

In 2015, the Swedish Academy of Sciences of the Nobel Prize for Medicine to three researchers, separately, explained how cells work at the molecular level to repair damaged DNA. They showed their works every day there are processes & # 39; repair & # 39; damage inside the human body, as well as inside the body of all plants and animals. However, when the repair mechanisms fail, it seems different diseases.

These pioneers in the discovery of & # 39; & # 39 mechanisms; DNA repair Tomas Lindahl, Paul Modrich and Aziz SANCAR. His studies began decades & # 39; years before, but now its products begin to benefit people.

PRECISION AGAINST LEWEMEMIJA. This 2018, Mexico was the first country in the world approved the use of & # 39; & # 39 new type; therapy called "a & # 39; precision medicine" against cancer & # 39; white blood cell type Leukemia Chronic lymphocytic (CLL).

The new treatment, which was approved by the Mexican health authorities last week & # 39; May by the US government a week later, on 7 & # 39; June, because innovation is correct molecular error that prevents cancer cells die. Acting on a particular structure or "sensor" of & # 39; diseased cells, treatment is considered a drug & # 39; accuracy.

The authorization for the use of & # 39; this treatment in Mexico was issued by the Federal Commission for Protection against Sanitary Risks (Cofepris) and given to biotechnology laboratory Mexico AbbVie, who carried multinational study – called Murano – to support the action of the new treatment.

The Chronic Lymphocytic Leukemia (CLL) is a type of & # 39; slow cancer in the bone marrow and blood, which types & # 39; white blood cells called lymphocytes become cancerous and multiply b & # 39; abnormal way. It is one of the most common types & # 39; leukemia in adults, accounting for 30 percent of leukemija b & # 39; value & # 39; prevalence twice in men than in women.

By causing the death of & # 39; diseased cells replace chemotherapy in the eradication of cancer cells, which has adverse effects. This therapy has been presented, f & # 39; Chicago, at the meeting of the American Society for Cancer and Oncology (ASCO), which ended on 5 & # 39; June.

Although it sounds strange, the underlying problem with & # 39; & # 39 different types; cancer is that cells seem to never die. Each cell b & # 39; her health has a life time and having completed its cycle, birth, growth and reproduction want to die, but the circumstances of the cancer cells have an error & # 39; information where genetic instructions dying disappeared.

B & # 39; this way, when a cell is tmutx, ie, when its process called apoptosis does not occur, begins to reproduce and accumulate or form & # 39; large tumors. When those cells that die or undergo organ and spread water from different parts of the body, starting the so-called metastasis.

The drug & # 39; precision seeks to correct the mistake molecular prevent cells from dying and trying to return the original instructions & # 39; apoptosis or cell death continued after the complete life cycle.

F & # 39; in June, explained Dr. Eduardo Edmundo Gómez Reynoso, a specialist in hematology at the Hospital Español de México Chronicle that the new treatment helps people with & # 39; CLL to live more without worsening the disease, compared to & # 39; chemo standard immunotherapy, which offers deep and fixed schedules remissions, but b & # 39; increased toxicity.

CANCER RIGHT BRAKE. Another & # 39; areas in which the drug & # 39; precision already providing benefits within the population is to extend the life & # 39; patients who were diagnosed with & # 39; incurable lung cancer, remaining before & # 39; only between two and four & # 39; months can now be treated with & # 39; this type of & # 39; medication to correct alterations produced by errors in DNA copy and b & # 39; so help increase survival on average & # 39; 18 months, but with & # 39; incurable documented cases where patients have survived three and a half or four & # 39; years.

Some of these cases occurred in the same geographical region in which Mexico, as presented by oncologists from Argentina and Costa Rica in the Latin American Seminar on Pfizer Lung Cancer made it ix- in a month & # 39; Bus Buenos Aires.

There, the message to be optimistic in the fight against lung cancer has been highlighted, but it should also be understood that m & # 39; no medicine for all patients and in Latin America, most patients are diagnosed when their cancer is already incurable lung.

"The most profound change that has taken place to give relief to these patients is that in the last four & # 39; years, with the approval and use of & # 39; new group & # 39; called treatments medicines & # 39; precision, can correct genetic mutations that cause the appearance & # 39; tumors in the lungs ", explained him Chronicle Dr. Luis Corrales, onkliniku at the Research Center and the Cancer Management, San José, Costa Rica.

"The mutations occur in a gene change position or change in the chromosome (which are in the core of & # 39; each cell). When these changes affect any existing membrane protein & # 39; each cell and function as receptors & # 39; biochemical orders. If these proteins are bad, stay & # 39; on & # 39; and send signals to cells reproduce without stopping. This is how form tumors. This is because there are new drugs that correct genetic mutation and disorder interrupt those signals to call the cells to reproduce out of control, "said Costa Rican expert.

The most repeated key message at a medical meeting was "before giving chemotherapy to patients with & # 39; lung cancer, has become molecular test", whereas patients who are treated with & # 39; chemotherapy and harm them. While there are patients & # 39; lung cancer can use drugs that correct genetic alterations, without using standard chemotherapy.

"We are living a change in strategy or paradigm of treatment", told this newspaper Dr. Diego Kaen, head & # 39; oncology at the university hospital of the National University & # 39; La Rioja, Argentina.

"The most treatments used to correct mutations are those that influence the activity & # 39; two proteins in the cell membrane and called EGFR and ALK +. Both influence the multiplication the cells and if correct, the tumor decreases and the quality of life of the patient improve a lot, "said Dr. Kaen, agreed to this change began in 2014.

"There are currently patients at 3 years and a half and four & # 39; years living with & # 39; lung cancer. The median survival is & # 39; 18 months, but before they lived only 4 months and only physicians sent them to fix legal affairs and their families before they died, "said the same doctor, who is head & # 39; Clinical research in Oncológico Riojano Integral Center (CORI).

Gene Editing. Besides Medicine & # 39; High Precision, f & # 39; the last two years created a spectacular news in the world of basic science related to & # 39; Other techniques for repairing & # 39; DNA errors, titled "gene editing".

This technology can & # 39; be explained if we think of & # 39; scissors are programmed to cut specific part of the DNA molecule where we make the correction or editing. Those scissors are molecules called CRISPR-Cas9.

F & # 39; this gene edition, what is wrong is cut, but external nothing is fixed because what happens is that when cut, response & # 39; DNA repair is activated in specific site became intervention.

The new tool for 'editing' genome, called CRISPR-Cas9 been tested with & # 39; successful 28 & # 39; October 20016, in China, where patients with & # 39; lung cancer was treated b & # 39; & # 39 with success; edited cells.

F & # 39; then, the commercial landscape of the CRISPR-Cas9 therapies was uncertain due to legal battle over patent rights in the United States on the technique of gene editing. The problem is fixed in the Patent Office and Trademark Office that the US has an obligation to determine who invented the technique for the first time.

However, the high benefits that this technology promises continued drive in the lab and, a year later, on 2 & # 39; August 2017, in & # 39; historical fact science, researchers from the US, -Ċina and Korea t & # 39; South managed to correct for the first time in human embryos is a hereditary disease, thanks to the use of the same technique & # 39; genetic editing.

Their work corrected the mutation & # 39; gene that produces a pathology called hypertrophic cardiomyopathy suffering than 500 people and is the most common cause of & # 39; Death in & # 39; & # 39 getting, athletes.

To conduct the experiments, oocytes and zygotes were produced by fertilizers with & # 39; & # 39 with health, sperm from a donor carrying MYBPC3 gene mutation, which causes the disease.

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