Faculty Collaboration Database

PIK3CA mutations in patients with advanced cancers treated with PI3K/AKT/mTOR axis inhibitors. Mol Cancer Ther 2011 Mar;10(3):558-65

Date

01/11/2011

Pubmed ID

21216929

Pubmed Central ID

PMC3072168

DOI

10.1158/1535-7163.MCT-10-0994

Scopus ID

2-s2.0-79952690921 (requires institutional sign-in at Scopus site)   303 Citations

Abstract

Preclinical data suggest that PIK3CA mutations predict response to PI3K/AKT/mTOR inhibitors. Concomitant KRAS or BRAF mutations may mediate resistance. Therefore, tumors from patients referred to the phase I program for targeted therapy starting in October 2008 were analyzed for PIK3CA mutations using PCR-based DNA sequencing of exons 9 and 20. Consecutive patients with diverse tumor types and PIK3CA mutation were treated whenever possible with agents targeting the PI3K/AKT/mTOR pathway. Overall, PIK3CA mutations were detected in 25 of 217 patients (11.5%; exon 9, n = 11; exon 20, n = 14). In tumor types with more than 10 patients tested, PIK3CA mutations were most frequent in endometrial (3 of 14, 21%), ovarian (5 of 30, 17%), colorectal (9 of 54, 17%), breast (2 of 14, 14%), cervical (2 of 15, 13%), and squamous cell cancer of the head and neck (1 of 11, 9%). Of the 25 patients with PIK3CA mutations, 17 (68%) were treated on a protocol that included a PI3K/AKT/mTOR pathway inhibitor, and 6 (35%) achieved a partial response. In contrast, only 15 of 241 patients (6%) without documented PIK3CA mutations treated on the same protocols responded (P = 0.001). Of the 17 patients with PIK3CA mutations, 6 (35%) had simultaneous KRAS or BRAF mutations (colorectal, n = 4; ovarian, n = 2). Colorectal cancer patients with PIK3CA and KRAS mutations did not respond to therapy, whereas both ovarian cancer patients with PIK3CA and KRAS or BRAF mutations did. In conclusion, PIK3CA mutations were detected in 11.5% of patients with diverse solid tumors. The response rate was significantly higher for patients with PIK3CA mutations treated with PI3K/AKT/mTOR pathway inhibitors than for those without documented mutations.

Author List

Janku F, Tsimberidou AM, Garrido-Laguna I, Wang X, Luthra R, Hong DS, Naing A, Falchook GS, Moroney JW, Piha-Paul SA, Wheler JJ, Moulder SL, Fu S, Kurzrock R

Author

Razelle Kurzrock MD Center Associate Director, Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adolescent
Adult
Aged
Aged, 80 and over
Class I Phosphatidylinositol 3-Kinases
Female
Humans
Male
Middle Aged
Mutation
Neoplasms
Phosphatidylinositol 3-Kinases
Polymerase Chain Reaction
Proto-Oncogene Proteins
Proto-Oncogene Proteins B-raf
Proto-Oncogene Proteins c-akt
Proto-Oncogene Proteins p21(ras)
TOR Serine-Threonine Kinases
Treatment Outcome
ras Proteins