A172 cells are a human cell line established from a glioblastoma, an aggressive brain tumor. These cells are immortalized, meaning they can divide and grow indefinitely in a lab, making them a renewable resource for scientific study. Researchers use A172 cells as a model to investigate brain cancer biology and explore potential treatments. Their characteristics provide a window into the mechanisms that drive tumor growth.
Origin and Key Characteristics
The A172 cell line was established from brain tumor tissue removed from a 53-year-old male patient diagnosed with glioblastoma multiforme. In lab cultures, these cells are adherent, meaning they attach and spread out on the surface of culture dishes, exhibiting a morphology described as epithelial-like. This growth pattern dictates how they are handled and studied.
Genetically, A172 cells are defined by significant abnormalities. They are hypertriploid, meaning they have more than three sets of chromosomes, with a total count of around 80 chromosomes per cell, including over 20 abnormal marker chromosomes. This aneuploidy, or abnormal number of chromosomes, is a hallmark of many cancers. A significant feature of the A172 line is its status regarding the TP53 gene. While some studies have reported it as having a wild-type (normal) p53 gene, others have detected no p53 protein, suggesting a functional loss that is common in glioblastomas.
Research Applications
The biological and genetic profile of A172 cells makes them applicable to a wide range of research. A primary application is in oncology for studying glioblastoma. Researchers use A172 cells to screen potential anti-cancer drugs, evaluating how different compounds affect cell viability, proliferation, and death. Their gene expression profile, which includes high levels of genes that promote angiogenesis (the formation of new blood vessels), allows for investigations into how tumors build their own blood supply.
Beyond cancer drug screening, A172 cells are employed in neuroscience to understand the biology of glial cells, the cell type from which glioblastomas arise. These studies help illuminate the normal functions of these brain cells and how they are corrupted during tumor formation. The cell line is also used in virology. For instance, A172 cells have been used to study how neurotropic viruses, such as the Zika virus, infect human brain cells. Research has shown that A172 cells express the AXL receptor, which the Zika virus uses to enter and infect the cells, providing a model to investigate viral entry mechanisms and potential antiviral therapies.
Cell Culture and Handling
Maintaining A172 cells in a lab requires controlled conditions to ensure their health for experiments. The cells are grown in a base medium called Dulbecco’s Modified Eagle’s Medium (DMEM). This medium is supplemented with 10% fetal bovine serum (FBS) for growth factors, and often antibiotics like penicillin and streptomycin to prevent bacterial contamination.
They are kept in an incubator set to a constant temperature of 37°C. The atmosphere is also controlled, maintained at 5% carbon dioxide (CO2) to ensure the culture medium remains at a stable, physiological pH.
As the cells grow and divide, they cover the surface of the culture flask. To maintain a healthy population, they must be regularly subcultured, or “passaged.” This process involves detaching the adherent cells from the flask surface using a reagent like trypsin or Accutase, which breaks the proteins that anchor the cells. The detached cells are then diluted and transferred into new flasks with fresh medium.
Significance in Glioblastoma Research
The A172 cell line is significant in glioblastoma research because its genetic makeup mirrors aspects of the human disease. Its functional loss of the p53 tumor suppressor protein is a feature shared with 30-50% of glioblastomas. This allows scientists to use A172 cells to investigate cellular pathways affected by p53’s absence, providing insights into tumor progression and therapy resistance.
Compared to other glioblastoma cell lines like U87 MG, the A172 line offers advantages for specific research questions. For instance, A172 cells have been shown to be more radiosensitive than the p53-mutant T98G cell line in some studies, making them useful for exploring the mechanisms of radiation therapy.
This ability to represent a specific subtype of glioblastoma makes the A172 cell line a valuable tool. It allows for controlled, repeatable experiments that can dissect the molecular drivers of tumor growth. By studying these cells, researchers can identify vulnerabilities that may not be apparent in other models, helping to develop more targeted therapies for this form of brain cancer.