Medication delivered in a gel stops brain tumors in mice. Could it offer hope for humans?
https://medicalxpress.com/news/2023-04- ... -mice.html
by Johns Hopkins University
Medication delivered by a novel gel cured 100% of mice with an aggressive brain cancer, a striking result that offers new hope for patients diagnosed with glioblastoma, one of the deadliest and most common brain tumors in humans.
"Despite recent technological advancements, there is a dire need for new treatment strategies," said Honggang Cui, a Johns Hopkins University chemical and biomolecular engineer who led the research. "We think this hydrogel will be the future and will supplement current treatments for brain cancer."
Cui's team combined an anticancer drug and an antibody in a solution that self-assembles into a gel to fill the tiny grooves left after a brain tumor is surgically removed. The gel can reach areas that surgery might miss and current drugs struggle to reach to kill lingering cancer cells and suppress tumor growth. The results are published today (April 24) in Proceedings of the National Academy of Sciences.
Researchers ID novel treatment pathway for deadly pancreatic cancers
https://medicalxpress.com/news/2023-04- ... eatic.html
by Johns Hopkins University School of Medicine
Researchers at the Johns Hopkins Kimmel Cancer Center identified a novel cell signaling pathway that potentially could be targeted in therapy for patients with aggressive pancreatic cancers.
In laboratory studies with human pancreatic cancer cell lines and genetically engineered mouse models of pancreatic cancer, the investigators discovered that the High Mobility Group A1 (HMGA1) protein functions as a "molecular switch" that "flips on" genes required by tumor cells to grow in an uncontrolled fashion and form invasive tumors.
One of these genes activated by HMGA1 leads to the production of fibroblast growth factor 19 (FGF19), which is secreted by tumor cells. FGF19 not only provides signals that coax tumor cells to grow rapidly and invade surrounding tissues, but both HMGA1 and FGF19 cooperate to "build" a dense, fibrous, scar-like wall around the tumor cells, which is known as the stroma. Pancreatic tumors are among a few tumors that form a dense stroma, and the stroma is thought to create a barrier preventing therapy from reaching the tumor cells.
When the scientists silenced HMGA1 or disrupted FGF19 signals in mouse models of pancreatic cancer, tumor cells had markedly decreased growth and less stroma formation, suggesting that drugs to block FGF19 signals already available for use by patients with other diseases could be repurposed to treat pancreatic tumors that have high levels of FGF19. Studies of cancer genomes indicate that up to a quarter of human pancreatic cancers have high levels of HMGA1 and FGF19.
A description of the work was published in The Journal of Clinical Investigation.
New tool charts differentiation landscape of acute myeloid leukemia
https://medicalxpress.com/news/2023-04- ... eloid.html
by Center for Genomic Regulation
Researchers have developed a new method to distinguish between cancerous and healthy stem cells and progenitor cells from samples of patients with acute myeloid leukemia (AML), a disease driven by malignant blood stem cells that have historically been difficult to identify. The findings, published today in the journal Cell Stem Cell, pave the way for the development of new techniques to predict whether patients will respond to chemotherapy.
AML is a type of cancer characterized by the rapid growth and accumulation of abnormal white blood cells. It is thought to develop when blood progenitor cells, which normally turn into all other types of blood cells, fail to mature properly and become abnormal. In this process, blood stem cells carry a special importance because they give rise to progenitor cells and are thought to be the cell type in which leukemic mutations occur.
Leukemic stem cells are thought to survive chemotherapy and cause relapse. High relapse rates are a major clinical problem in AML and a frequent cause of patient death.
Understanding how blood stem cells give rise to blood progenitor cells in the context of AML is crucial for improving our understanding of the disease, developing better diagnostic and prognostic tools, and identifying new therapeutic targets and treatments. However, this has been historically difficult because of the high degree of variability between patients and the similarity between healthy and malignant stem cells.