Skip to main content
Article thumbnail
Location of Repository

Detection of K-Ras mutations in tumour samples of patients with non-small cell lung cancer using PNA-mediated PCR clamping

By M Beau-Faller, M Legrain, A-C Voegeli, E Guérin, T Lavaux, A-M Ruppert, A Neuville, G Massard, J-M Wihlm, E Quoix, P Oudet and M P Gaub

Abstract

Non-small cell lung cancers (NSCLC), in particular adenocarcinoma, are often mixed with normal cells. Therefore, low sensitivity of direct sequencing used for K-Ras mutation analysis could be inadequate in some cases. Our study focused on the possibility to increase the detection of K-Ras mutations in cases of low tumour cellularity. Besides direct sequencing, we used wild-type hybridisation probes and peptide-nucleic-acid (PNA)-mediated PCR clamping to detect mutations at codons 12 and 13, in 114 routine consecutive NSCLC frozen surgical tumours untreated by targeted drugs. The sensitivity of the analysis without or with PNA was 10 and 1% of tumour DNA, respectively. Direct sequencing revealed K-Ras mutations in 11 out of 114 tumours (10%). Using PNA-mediated PCR clamping, 10 additional cases of K-Ras mutations were detected (21 out of 114, 18%, P<0.005), among which five in samples with low tumour cellularity. In adenocarcinoma, K-Ras mutation frequency increased from 7 out of 55 (13%) by direct sequencing to 15 out of 55 (27%) by clamped-PCR (P<0.005). K-Ras mutations detected by these sensitive techniques lost its prognostic value. In conclusion, a rapid and sensitive PCR-clamping test avoiding macro or micro dissection could be proposed in routine analysis especially for NSCLC samples with low percentage of tumour cells such as bronchial biopsies or after neoadjuvant chemotherapy

Topics: Molecular Diagnostics
Publisher: Nature Publishing Group
OAI identifier: oai:pubmedcentral.nih.gov:2661785
Provided by: PubMed Central
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://www.pubmedcentral.nih.g... (external link)
  • Suggested articles

    Citations

    1. (2001). Blocking oncogenic Ras signalling for cancer therapy.
    2. (2006). Distinct epidermal growth factor receptor and KRAS mutation patterns in nonsmall cell lung cancer patients with different tobacco exposure and clinicopathologic features.
    3. (2008). Dobrovic A
    4. (2004). EGFR mutations in lung cancer: correlation with clinical response to gefitinib therapy.
    5. (1991). Oncol 3(4): 331–339 Bishop JM
    6. (1999). sprognostic indicator in patients with non-small-cell lung cancer.

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.