Fonte de imagem: MIT News
Scientists in California have discovered that a newly developed drug prevents pancreatic cancer in lab mice.
The study, led by non-profit health science centre Cedars-Sinai, also demonstrated in mice that the drug, called Metavert, may prevent patients from developing a resistance to currently used pancreatic cancer chemotherapies.
Commenting on the potential impact of their findings, study lead author Mouad Edderkaoui PhD, assistant professor of Medicine and Biomedical Sciences at the Samuel Oschin Comprehensive Cancer Institute at Cedars-Sinai, said: “This is an exciting step toward improving survival rates in pancreatic cancer patients.
If the results are confirmed in humans, we could have a drug with the potential to significantly extend the lives of patients with pancreatic ductal adenocarcinoma (PDAC), which is very difficult to treat.”
Pancreatic cancer is the third-leading cause of cancer-related death in the United States, according to the American Cancer Society. This year, around 55,000 people in the U.S. will be diagnosed with the disease and more than 44,000 will die, making it one of the most deadly cancers. The pancreatic cancer five-year survival rate is only 7%.
95% of pancreatic cancer patients are diagnosed with PDAC, which develops from cells that line small tubes in the pancreas. PDAC can be difficult to treat because the cancer cells prompt normal cells that reside in the pancreas – called stellate cells – to produce pancreatic scar tissue. Scar tissue makes it difficult for chemotherapy agents and blood to enter the pancreas, explained the senior author of the study, Stephen J. Pandol MD, director of Basic and Translational Pancreas Research at Cedars-Sinai.
The cancer-stellate cell interaction also creates an environment that stimulates local tumour growth as well as cancer that spreads to distant sites in the body, said Pandol, a professor of Medicine at Cedars-Sinai. Additionally, the activity levels of certain enzymes increase significantly, which fuels resistance to cancer treatments.
“I’ve seen patients who respond to therapy for a while, and then the disease takes off because the cancer becomes smart – it blocks chemotherapy from working,” Pandol said. “Metavert targets that action.”
Over a four-year period, the investigators designed and synthesised new chemicals that inhibit cancer cell activity. They discovered that Metavert blocked drug resistance and also significantly boosted the positive effects of radiation and two chemotherapy agents commonly used in humans. In one of the mouse studies, Metavert increased the survival rate by about 50%.
According to Pandol, the investigators are currently developing a version of the drug to test in humans.
The study was published in the journal Gastroenterology.
Fonte de imagem: Dr. Willian Rezende
A criança já tinha feito um transplante de medula, mas a doença havia voltado a manifestar-se.
Álvaro tem apenas seis anos, mas uma história de vida sofrida. Ainda era bebé quando lhe foi diagnosticada uma leucemia linfoblástica aguda de tipo B. Desde então foi submetido aos tratamentos aplicados nestes casos, tendo feito, inclusive, um transplante de medula. Mas ainda assim, a doença voltou sempre para atormentar o pequeno Álvaro.
Porém, tudo mudou no outono passado quando os médicos optaram por seguir uma técnica pioneira na cura desta doença e à qual foi dado o nome de CAR-T 19.
Esta técnica, que em Espanha só é levada a cabo em apenas três hospitais (dois em Barcelona e um em Madrid), ajuda o sistema imunitário a reconhecer, atacar e destruir as células cancerígenas de uma forma direcionada. Para isso é retirado sangue ao paciente com recurso a um método que separa todos os componentes do sangue – desta forma os médicos conseguem obter os linfócitos T.
Estes linfócitos, explica o jornal catalão La Vanguardia, são modificados em laboratório e ‘programados’ para reconhecerem de imediato as células cancerígenas e logo as atacarem e destruírem.
Depois de alterados, os linfócitos são colocados no sangue do paciente que, segundo a teoria, pode voltar a ter uma vida normal ao fim de três meses.
E, felizmente, não é apenas a teoria que o diz. O responsável pela equipa médica do Hospital Sant Joan de Déu, em Barcelona, disse, esta quinta-feira em conferência de imprensa, que Álvaro está curado, podendo regressar a casa para “ter uma vida normal e desfrutar” da mesma.
Aos jornalistas, o especialista Miquel Pons revelou ainda que este foi o primeiro caso totalmente financiado pelo sistema público de saúde espanhol que aplicou mais de 320 mil euros no tratamento do pequeno Álvaro.
The gene-editing tool has been used in a trial to enhance the blood cells of two patients with cancer, according to NPR.
The trial: The experimental research, under way at the University of Pennsylvania, involves genetically altering a person’s T cells so that they attack and destroy cancer. A university spokesman confirmed it has treated the first patients, one with sarcoma and one with multiple myeloma.
Slow start: Plans for the pioneering study were first reported in 2016, but it was slow to get started. Chinese hospitals, meanwhile, have launched a score of similar efforts. Carl June, the famed University of Pennsylvania cancer doctor, has compared the Chinese lead in employing CRISPR to a genetic Sputnik.
Ex vivo: It’s safer and easier to employ the CRISPR technique on cells removed from a patient’s body. That’s the case in the new cancer study, in which doctors collected blood from patients and then genetically engineered the immune cells present in it before returning the cells to the patients.
The edit: Researchers added one gene to make the T cells attack cancer, but they also used CRISPR to delete a different gene, called PD-1, which can act as a brake on the immune system’s defenses.
Pharmaceutical drugs that inhibit PD-1, known as immunotherapies, have been dramatically effective in treating a few cancers. Now the idea is to install the same capacity directly into the DNA of T cells.
CRISPR wave: The Pennsylvania cancer study is just one of many tests of medical treatments using CRISPR that are on the way. This year, for example, a patient in Europe became the first person to be treated with CRISPR for an inherited disease, beta thalassemia.
Funding: The Penn study is funded by the Parker Institute for Cancer Immunotherapy, an organization started by Napster cofounder and early Facebook investor Sean Parker, as well as by a startup firm, Tmunity. Parker has likened T cells to “little computers” that can be reprogrammed.