Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Clinical Trial
. 2014 Jan 30;6(2):377-87.
doi: 10.1016/j.celrep.2013.12.035. Epub 2014 Jan 16.

Assessing PIK3CA and PTEN in early-phase trials with PI3K/AKT/mTOR inhibitors

Affiliations
Clinical Trial

Assessing PIK3CA and PTEN in early-phase trials with PI3K/AKT/mTOR inhibitors

Filip Janku et al. Cell Rep. .

Abstract

Despite a wealth of preclinical studies, it is unclear whether PIK3CA or phosphatase and tensin homolog (PTEN) gene aberrations are actionable in the clinical setting. Of 1,656 patients with advanced, refractory cancers tested for PIK3CA or PTEN abnormalities, PIK3CA mutations were found in 9% (146/1,589), and PTEN loss and/or mutation was found in 13% (149/1,157). In multicovariable analysis, treatment with a phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) inhibitor was the only independent factor predicting response to therapy in individuals harboring a PIK3CA or PTEN aberration. The rate of stable disease ≥6 months/partial response reached 45% in a subgroup of individuals with H1047R PIK3CA mutations. Aberrations in the PI3K/AKT/mTOR pathway are common and potentially actionable in patients with diverse advanced cancers. This work provides further important clinical validation for continued and accelerated use of biomarker-driven trials incorporating rational drug combinations.

PubMed Disclaimer

Conflict of interest statement

CONFLICT OF INTEREST

Filip Janku has research support from Novartis. Razelle Kurzrock has research support from GlaxoSmithKline, Novartis, Merck, and Bayer.

Figures

Figure 1
Figure 1
Proportion of PIK3CA mutations and PTEN aberrations in 1,090 patients who had both PIK3CA and PTEN testing.
Figure 2
Figure 2
PIK3CA mutations are more frequent in tumors with simultaneous KRAS mutations (42/225, 19% vs. 89/975, 9%; p<0.001).
Figure 3
Figure 3
Therapies targeting the PI3K/AKT/mTOR pathway. Most patients (104, 76%) received mTORC1 inhibitor (rapalog)-based therapy, 20 (15%) PI3K inhibitor-based therapy, 6 (4.5%) dual PI3K and mTOR kinase inhibitor-based therapy, and 6 (4.5%) AKT inhibitor-based therapy.
Figure 4
Figure 4
Waterfall plot shows best response for patients with PIK3CA mutations or PTEN aberrations treated with PI3K/AKT/mTOR inhibitors. Of the 136 treated patients, 135 are depicted in the waterfall plot (one patient died of unrelated causes prior to her first restaging). A total of 25 PRs and 33 minor regressions less than PR were observed. The overall PR rate was 18%.
Figure 5
Figure 5
Kaplan-Meier plot for progression-free survival (PFS). Tick marks represent patients who were progression-free at last follow up and are censored at that point. A. Patients with PIK3CA mutations and/or PTEN aberrations treated with combination therapies (yellow, n=95) compared to patients treated with single-agent therapies (blue, n=41) had a longer median PFS than (3.0 months, 95% CI 2.0–4.0 vs. 1.8 months, 95% CI 1.6–2.0; p<0.001). B. Patients with PIK3CA mutations and/or PTEN aberrations and simultaneous KRAS mutations in codon 12 or 13 (yellow) compared to patients without KRAS mutations in codon 12 or 13 (blue) had a shorter median PFS compared to 81 (1.8 months, 95% CI 1.6–2.0 vs. 2.9 months, 95% CI 1.9–3.9; p=0.004). C. Patients with a H1047R mutation (yellow) compared to patients with other PIK3CA mutations (blue) had a longer median PFS (4.6 months, 95% CI 0.6–8.6 vs. 2 months, 1.6–2.4; p=0.03).

References

    1. Bader AG, Kang S, Vogt PK. Cancer-specific mutations in PIK3CA are oncogenic in vivo. Proc Natl Acad Sci U S A. 2006;103:1475–1479. - PMC - PubMed
    1. Bang YJ, Van Cutsem E, Feyereislova A, Chung HC, Shen L, Sawaki A, Lordick F, Ohtsu A, Omuro Y, Satoh T, et al. Trastuzumab in combination with chemotherapy versus chemotherapy alone for treatment of HER2-positive advanced gastric or gastro-oesophageal junction cancer (ToGA): a phase 3, open-label, randomised controlled trial. Lancet. 2010;376:687–697. - PubMed
    1. Cheung LW, Hennessy BT, Li J, Yu S, Myers AP, Djordjevic B, Lu Y, Stemke-Hale K, Dyer MD, Zhang F, et al. High frequency of PIK3R1 and PIK3R2 mutations in endometrial cancer elucidates a novel mechanism for regulation of PTEN protein stability. Cancer Discovery. 2011;1:170–185. - PMC - PubMed
    1. Cox D. Regression models and life tables (with discussion) J R Statistical Soc, B. 1972;34:187–220.
    1. De Roock W, Claes B, Bernasconi D, De Schutter J, Biesmans B, Fountzilas G, Kalogeras KT, Kotoula V, Papamichael D, Laurent-Puig P, et al. Effects of KRAS, BRAF, NRAS, and PIK3CA mutations on the efficacy of cetuximab plus chemotherapy in chemotherapy-refractory metastatic colorectal cancer: a retrospective consortium analysis. Lancet Oncol. 2010;11:753–762. - PubMed

Publication types

MeSH terms

Substances