City scientists crack puzzle in brain tumour research

Bengaluru: Scientists from the Indian Institute of Science (IISc) and the National Institute of Mental Health and Neurosciences (Nimhans) have unravelled some crucial aspects of glioblastoma, the most common brain tumour.
I n a study published in a recent issue of Neuro-Oncology, Prof Paturu Kondaiah of IISc, the study's lead member, said, "The most important insight is the revelation that in glioblastoma cells, IGFBP2 acts as a tumour promoter through a well-known pathway, beta-catenin." IGFBP2 is a binding protein alike insulin.Fluids like blood plasma surround the cells in the human body and IGFBP2 is present in these fluids.
While scientists point out that previous studies have shown patients with more aggressive forms of glioblastoma had higher IGFBP2 levels in their serum, they said: "However, the question of how IGFBP2 makes the tumour aggressive remained unanswered until now."
Unlike IGFBP2, beta catenin is another protein that keeps shuttling in and out of the cell's nucleus. When inside, it influences protein production. A group of proteins in the nucleus collectively degrade beta catenin, keeping it preferentially on the cell membrane. The researchers observed a strong correlation between extracellular IGFBP2 and nuclear beta catenin levels.
Beta catenin could induce production of new proteins that instruct tumour cells to proliferate faster than normal, and start invading other tissues. "We're orking on further delineation of the pathway and other players involved in IGFBP2 mediated tumour promotion," said Kondaiah.