Method of determining the sensitivity of cancer cells to EGFR inhibitors including cetuximab, panitumumab and erlotinib
View Patent ↗A method of determining if a cancer patient is amenable to treatment with EGFR inhibitors including but not limited to cetuximab, panitumumab or erlotinib by the following steps: (a) Obtaining cells from a cancer patient's tumor; (b) Determining if said cells contain a biomarker that is predictive of a therapeutic response to response to treatment with cetuximab or panitumumab. The biomarker is the mutation status of the PIK3CA gene and the expression status of the PTEN gene. Tumors that harbor activating mutations in Exon 9 and 20 of the PIK3CA gene or which show loss of PTEN protein expression will be considered not likely to benefit from EGFR targeting therapies.
1. A method of determining if a cancer patient is amenable to treatment with an EGFR inhibitor which comprises determining the mutation status of the PIK3CA gene in a tumor from the cancer patient, wherein an activating mutation in the PIK3CA gene is indicative that the patient is not likely to benefit from treatment with the EGFR inhibitor.
2. The method of claim 1 , wherein the activating mutation is in exon 9 of the PIK3CA gene.
3. The method of claim 1 , wherein the activating mutation is in exon 20 of the PIK3CA gene.
4. The method of claim 1 , wherein the activating mutation is in both exon 9 and exon 20 of the PIK3CA gene.
5. The method of claim 1 , wherein the tumor is a solid tumor.
6. The method of claim 1 , wherein the tumor is a colon tumor, a lung tumor, a breast tumor or a gastric tumor.
7. The method of claim 1 , wherein the EGFR inhibitor is a small molecule or a monoclonal antibody.
8. The method of claim 1 , wherein the EGFR inhibitor is cetuximab, erlotinib, gefitinib or panitumumab.
9. The method of claim 1 , which comprises selecting a patient who does not have an activating mutation in the PIK3CA gene for therapy with an EGFR inhibitor.
10. The method of claim 1 , wherein the mutation status of the PIK3CA gene is determined by isolating DNA from cells isolated from the tumor and determining if the DNA has a mutation in the PIK3CA gene.
11. The method of claim 1 , which comprises selecting a patient who does have an activating mutation in the PIK3CA gene for therapy with a cancer therapeutic that is not an EGFR inhibitor.