TY - JOUR
T1 - EGFR dinucleotide repeat polymorphism as a prognostic indicator in non-small cell lung cancer
AU - Dubey, Sarita
AU - Stephenson, Patricia
AU - Levy, Donna E.
AU - Miller, Judith A.
AU - Keller, Steven M.
AU - Schiller, Joan H.
AU - Johnson, David H.
AU - Kolesar, Jill M.
PY - 2006/6
Y1 - 2006/6
N2 - BACKGROUND: The epidermal growth factor receptor (EGFR) has been implicated in tumor growth and progression. Intron 1 of the EGFR gene contains a polymorphic simple sequence repeat (SSR) of 14 to 21 CA dinucleotides, the length of which correlates inversely with the level of EGFR transcription. The authors hypothesized that a shorter length of tumor SSR would be associated with poorer survival in patients with non-small cell lung cancer (NSCLC). METHODS: Patients enrolled in Eastern Cooperative Oncology Group E3590 (a randomized, prospective trial of adjuvant therapy following resection of stages II and IIIa NSCLC) were randomized to radiation or radiation plus chemotherapy. Genomic DNA extracted from resected tumors was amplified for EGFR intron 1 by polymerase chain reaction and sequenced in a 3730XL DNA analyzer. RESULTS: One hundred fifty-seven primary tumors were sequenced, 106 (68%) of which were heterozygous for intron 1. The most common genotypes were allele lengths of 17/19 dinucleotides (17.8%), 17/18 (11.4%), and 19/19 (11.4%). Allele status (homozygous versus heterozygous) did not correlate with race, gender, weight, performance status, histology, stage, or survival. Shorter allele length (≤18 versus >18 CA dinucleotide repeats) was associated with squamous cell histology (p = 0.03). Allele sum of greater than 35 was associated with improved overall survival (log-rank p = 0.03, hazard ratio = 0.66). CONCLUSION: This is the first study to characterize the EGFR intron 1 SSR polymorphism in NSCLC. Tumors were most commonly heterozygous for SSR length. Squamous histology was associated with a shorter SSR. Longer sequences are associated with improved survival.
AB - BACKGROUND: The epidermal growth factor receptor (EGFR) has been implicated in tumor growth and progression. Intron 1 of the EGFR gene contains a polymorphic simple sequence repeat (SSR) of 14 to 21 CA dinucleotides, the length of which correlates inversely with the level of EGFR transcription. The authors hypothesized that a shorter length of tumor SSR would be associated with poorer survival in patients with non-small cell lung cancer (NSCLC). METHODS: Patients enrolled in Eastern Cooperative Oncology Group E3590 (a randomized, prospective trial of adjuvant therapy following resection of stages II and IIIa NSCLC) were randomized to radiation or radiation plus chemotherapy. Genomic DNA extracted from resected tumors was amplified for EGFR intron 1 by polymerase chain reaction and sequenced in a 3730XL DNA analyzer. RESULTS: One hundred fifty-seven primary tumors were sequenced, 106 (68%) of which were heterozygous for intron 1. The most common genotypes were allele lengths of 17/19 dinucleotides (17.8%), 17/18 (11.4%), and 19/19 (11.4%). Allele status (homozygous versus heterozygous) did not correlate with race, gender, weight, performance status, histology, stage, or survival. Shorter allele length (≤18 versus >18 CA dinucleotide repeats) was associated with squamous cell histology (p = 0.03). Allele sum of greater than 35 was associated with improved overall survival (log-rank p = 0.03, hazard ratio = 0.66). CONCLUSION: This is the first study to characterize the EGFR intron 1 SSR polymorphism in NSCLC. Tumors were most commonly heterozygous for SSR length. Squamous histology was associated with a shorter SSR. Longer sequences are associated with improved survival.
KW - Allele
KW - Intron 1
KW - Simple sequence repeat
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U2 - 10.1097/01243894-200606000-00005
DO - 10.1097/01243894-200606000-00005
M3 - Article
C2 - 17409891
AN - SCOPUS:33846979362
SN - 1556-0864
VL - 1
SP - 406
EP - 412
JO - Journal of Thoracic Oncology
JF - Journal of Thoracic Oncology
IS - 5
ER -