Restriction fragment length polymorphism analysis of the l‐myc gene locus in a case‐control study of lung cancer

Abstract

The L-myc DNA-restriction fragment length polymorphism, revealed by EcoRI, has been studied in both a lung cancer case-control framework and a cohort of 40 non-diseased unrelated individuals. No association was found between the L-myc allelic frequencies and disease status, tumor stage or lung cancer histology. A strong association was, however, observed between the L-myc allelic frequencies and ethnic origin (black or white) of the subjects. Among American whites the allelic distribution at the L-myc proto-oncogene locus was almost identical to that previously reported for Japanese subjects. Among the American black population there was a significantly higher frequency of the presence of the polymorphic EcoRI restriction site in the second intron of the L-myc proto-oncogene. These data emphasize the importance of conducting epidemiologic studies that control for ethnic factors and indicate that L-myc EcoRI allelotypes do not appear to be predictive of lung cancer risk or disease status in American blacks and whites.

Meta-Analysis Suggests Association of L- myc Eco RI Polymorphism with Cancer Prognosis

“…In controls, the allelic frequency of the S allele was 0.458 in Caucasians (1661 subjects), 0.486 in Asians (1224 subjects), and 0.69 in a small number (13 individuals) of African-Amer- Caucasian 76 oral Ishizaki, 1990 Asian 117 breast, 60 gastric Tefre, 1990 Caucasian 83 lung Asian 101 sarcoma Tamai, 1990;Weston, 1992 Caucasian icans. A significant deviation from the Hardy-Weinberg equilibrium (P Ͻ 0.05) was seen in two studies in Caucasians and in three studies in Asians (Table 3).…”

MYC oncogenes and human neoplastic disease

“…Another problem is the lack of data showing expression of L-myc mRNA or protein in any of the tumors studied. The predictive value of L-MYC allelic di erences in lung cancer has been called into question by several subsequent studies (Tamai et al, 1990;Tefre et al, 1990;Weston et al, 1994).…”

MYCL genotypes and loss of heterozygosity in non-small-cell lung cancer

“…Conversely, this association has not been found in Caucasian (Norwegian and North American) lung cancer populations (Tamai et al, 1990;Tefre et al, 1990;Weston et al, 1992Weston et al, , 1994. While the conflicting results may have been owing to racial/ethnic differences, there were also significant methodological variations between the studies, such as case stratification, including heterogeneity in the subtypes of lung cancer, disease stage and treatment modalities; all factors which are known to affect tumour progression and outcome.…”

“…In addition, the SS genotype was more frequent in colorectal cancer patients than in young blood donor controls (Young et al, 1994). However, the cancer-susceptibility model is controversial, as the SS genotype appears to protect against hepatocellular cancer (Taylor et al, 1993), and the S allele was not increased in patients with lung cancer (Tamai et al, 1990;Weston et al, 1992Weston et al, , 1994, breast cancer (Champeme et al, 1992) or lymphoma/leukaemia (Chenevix-Trench et al, 1989).As regards tumour progression, Kawashima et al (1988, 1992), in an initial study followed by a larger study involving 252 Japanese lung cancer patients, showed that the S allele predisposed to metastases and adverse prognosis. Conversely, this association has not been found in Caucasian (Norwegian and North American) lung cancer populations (Tamai et al, 1990;Tefre et al, 1990;Weston et al, 1992Weston et al, , 1994.…”

“…In addition, the SS genotype was more frequent in colorectal cancer patients than in young blood donor controls (Young et al, 1994). However, the cancer-susceptibility model is controversial, as the SS genotype appears to protect against hepatocellular cancer (Taylor et al, 1993), and the S allele was not increased in patients with lung cancer (Tamai et al, 1990;Weston et al, 1992Weston et al, , 1994, breast cancer (Champeme et al, 1992) or lymphoma/leukaemia (Chenevix-Trench et al, 1989).…”