title: Comparative screening of K-ras mutations in colorectal cancer and lung cancer patients using a novel real-time PCR with ADx-K-ras kit and Sanger DNA sequencing.
abstract: We determined frequency/types of K-ras mutations in colorectal/lung cancer. ADx-K-ras kit (real-time/double-loop probe PCR) was used to detect somatic tumor gene mutations compared with Sanger DNA sequencing using 583 colorectal and 244 lung cancer paraffin-embedded clinical samples. Genomic DNA was used in both methods; mutation rates at codons 12/13 and frequency of each mutation were detected and compared. The data show that 91.4% colorectal and 59.0% lung carcinoma samples were detected conclusively by DNA sequencing, whereas 100% colorectal and lung samples were detected by ADx-K-ras kit. K-ras gene mutations were detected in 32.9-27.4% colorectal samples using kit and sequencing methods, respectively. Whereas 10.6-8.3% lung cancer samples were positively detected by kit and sequencing methods, respectively. Notably, 172/677 showed mutations and 467/677 showed wild type by both methods; 38 samples showed mutations with kit but wild type with sequencing. Mutations in colorectal samples were as follows: GGT → GAT/codon-12 (35.1%); GGC → GAC/codon-13 (26.6%); GGT → GTT/codon-12 (18.2%); and GGT → GCT/codon-12 (1.6%). Mutations in lung samples were as follows: GGT > GTT/codon-12 (40.9%) and GGT > GCT/codon-12 (4.5%). In conclusion, K-ras mutations involved 32.2% colorectal and 10.6% lung samples among this cohort. ADx-K-ras real-time PCR showed higher detection rates (P < 0.05). The kit method has good clinical applicability as it is simple, fast, less prone to contamination and hence can be used effectively and reliably for clinical screening of somatic tumor gene mutations.
authors: Department of Pathology, First Hospital of Xiamen, Xiamen University, Xiamen 361003, China. Zhp3398@163.com
authors: Haiping
authors: H
authors: Zhang
authors: Xiongwei
authors: X
authors: Zheng
authors: Tianhai
authors: T
authors: Ji
authors: Li
authors: L
authors: Fu
authors: Dongyu
authors: D
authors: Bai
authors: Yongqiang
authors: Y
authors: Liao
authors: Haifang
authors: H
authors: Zhang
authors: Yi
authors: Y
authors: Ding
authors: Limou
authors: L
authors: Zheng
mesh_terms: D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D005787:Gene Frequency; D005820:Genetic Testing / Q000379:methods*; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D009154:Mutation; D059645:Mutation Rate; D011933:Reagent Kits, Diagnostic; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D018631:ras Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D011933:Reagent Kits, Diagnostic; D018631:ras Proteins