Deficiency of the QKI Gene and Cancer

The University of Texas MD Cancer Center has concluded that the survival of cancer cells is possibly linked to the deficiency of a tumor suppressor gene called quaking. Quaking is also known as the QKI gene. The QKI gene is a huge contributor to the regulation of cancer stem cells in glioblastoma. Glioblastoma are the deadliest kind of brain tumor that one can have. The cells that make up these tumors, called glioma stem cells, are able to self-renew inexhaustibly until tumors are produced in the brain. The glioma cells self-renew by creating identical daughter cells when dividing. To maintain the process of cell division the glioma cells have to be in environments providing the proper cellular signals. 

When glioma cells are in optimal conditions, they are said to be in niches and can continue to divide. This increases the amount of cancer stem cells. Previous studies conducted proved that the QKI gene is a tumor suppressor that regulates cancer stem cells. In addition, QKI affects cellular activity by regulating endocytosis. This process is responsible for the degradation of receptors on the cell that allow the continuation of stem cell self-renewal. The increase in cell receptors due to deficiency of the QKI gene causes the cancer stem cells to divide in areas outside of the niches.  A defective QKI gene will result in an increase of the cell receptors on cancer stem cells. Therefore, the amount of glioma, cancer cells, can divide very rapidly even if they are located in areas outside of the niches. 

According to Dr. Jian Hu, assistant professor of the Department of Cancer Biology, the discovery of the deficient QKI gene may lead to alternative methods for therapeutic treatments of cancer. This is a great discovery. I feel that scientists are making great progress and learning so much about the destructive disease that we call cancer. Cancer has taken, and is still taking, the lives of so many people. Cancer does not discriminate by age or the current great health one may have. Scientists can work on gene therapy techniques with the QKI in the future to learn more about cancer. Consequently, I hope to see the development of a technique to isolate a working QKI gene to administer to individuals with a deficient QKI gene as a cancer treatment. It is great that scientists have discovered so much about the worst kind of tumor that one can have. 

Forensic DNA analysis checks the origin of cultured cells

"A cell line consists of cultured cells that often originate from a tumor."Unlike other cultured cells, cell line of tumor cells can be cultured for many years because these cells divide continually. A cell line U87MG used by the brain tumor type glioma was studied by the researchers at Uppsala university about fifty years ago. Marie Allen is an expert in DNA fingerprinting. DNA fingerprinting is used for finding out genetic identity such as in crime investigation scenes. Marie and her collegues genetically compared the cell lines with each other. It was found by that the U87MG cell line from the American Type Culture Collection (ATCC) had a different DNA profile than the original cell line in Uppsala. 

The material from the original tumor was saved as thin sections on microscope slides when the cell line was established in 1960s. The researchers could compare the two current cell lines with the tumor from which the cell line was established by using a very sensitive DNA analysis technique. This technique can also be used when very small quantities of DNA from old tissues are present. Consequently, the U87MG cell line from ATCC had a different and unknown origin while the Uppsala cell line was genetically similar to the original tumor. Bengt Westermark says, " We do not know at which point during the fifty years of culturing the mix-up occured but we have been able to show that the ATCC U87MG line is most likely from a human glioma tumor." Researchers who report results based on cell line experiment should use DNA profiling to establish the identity of used cells. Proper identification of a cell line requires that the DNA profile should match the origin of tissues. This is important if someone wants to assert that the cells are true representatives of original tumor through the research results. 

In my opinion, DNA profiling of human cell lines, which if applied routinely in cell culture experiment can significantly improve the recognition of cellular cross-contamination and thus results in more precise analysis. Human cell lines have been used as models for diseases such as cancer, production of vaccines and recombinant proteins. However, we need to moderate the accelerated use of human cell lines to prevent the cellular cross contamination.

http://health.economictimes.indiatimes.com/news/industry/forensic-dna-analysis-checks-the-origin-of-cultured-cells/53955496

https://www.sciencedaily.com/releases/2016/08/160831142856.htm