PIK3CA Gene Mutations in Cancer

The PIK3CA gene mutation (Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Alpha) is a gene which encodes a protein called p110, involved in cell processes like proliferation, growth, differentiation, motility, and survival. Once the mutation occurs in the PIK3CA gene, it creates abnormal p110 proteins at an increased rate. Eventually, these abnormal proteins develop into cancer. Due to the overproduction of proteins, cases of PIK3CA cancer tend to be more aggressive and have an overall worse prognosis than cancers without the gene mutation. Although some gene mutations can be inherited from your family, the PIK3CA is not hereditary. Therefore, anyone who has this gene mutation developed it over the course of their lifetime from an unknown cause.

The PIK3CA gene mutation is found in the following cancer types:

• Breast cancer
• Ovarian cancer
• Lung cancer
• Stomach (gastric) cancer
• Brain cancer

PIK3CA Gene Mutation Treatments

Although more aggressive than cancers without a mutation, PIK3CA gene mutation cancers are eligible for targeted therapies. Targeted therapies can detect specific abnormalities, or mutations, within cells, then attack them. New targeted therapies for PIK3CA are available in clinical trials where they are being evaluated for safety and efficacy by the FDA. These clinical trials are providing early access to treatment because they are not widely offered yet other than in clinical trials. Other treatment types can be given to patients with PIK3CA positive cancer, but it depends on the exact type and stage of the cancer.

The only FDA approved treatment for PIK3CA positive cancers is Piqray (alpelisib), which is a targeted therapy. This drug is only used in advanced cases of breast cancer, although PIK3CA does occur in other cancer types. Specifically, in those who are hormone receptor positive and HER2 negative. Although only one drug is currently approved by the FDA, there are many more that are being developed by researchers and offered in clinical trials.

New therapies being evaluated in clinical trials for PIK3CA positive cancers include:

• Dactolisib
• Apitolisib
• Gedatolisib
• Buparlisib
• Duvelisib
• Copanlisib
• Idelalisib
• Alpelisib
• Taselisib
• Pictilisib

Sources:

https://www.ncbi.nlm.nih.gov/article

https://medlineplus.gov/pik3ca