Cells throughout the body make proteins called fibroblast growth factor receptors (FGFR). These receptors live on the surface of cells and stick to fibroblast growth factors (FGFs) to act like antennas, receiving messages about how to help the cells grow, divide, and survive.
The receptors are numbered and talk to one another. There are four main FGFRs: FGFR1, FGFR2, FGFR3, and FGFR4. (There is also a unique type of receptor called FGFRL1.) These proteins can also be broken down into b and c (these are called isoforms).
When these receptors are working together and at healthy levels, the whole body stays healthy. But sometimes errors and defects happen as cells grow and divide.
All of the genes that create FGFR receptors can encounter errors, but the errors show up in different ways depending on the cancer type.
Sometimes, pieces of the FGFR gene break off. When the broken pieces stick to genes that are outside the FGFR family, this is called an FGFR fusion.
Some cancer cells have too many copies of an FGFR gene, this is called “amplification.” Too many copies of a gene can lead to too many receptors, which is called “overexpression.”
Biomarker testing can be run on tumor or blood samples to determine if a patient has an alteration with an FGFR gene. Drugs called "inhibitors" get inside cancer cells and block the signals telling the cancer to grow.
Cholangiocarcinoma (in advanced, specific situations)
There are several clinical trials happening for other GI cancer types with alterations in the FGFR genes.
Your treatment plan will be unique and dependent on several factors.
Ask your doctor how your biomarker test results are informing your treatment plan and if you qualify for any clinical trials.
