L‐myc Restriction Fragment Length Polymorphism in Japanese Patients with Esophageal Cancer

Abstract

L-myc polymorphism is a representative genetic trait related to an individual's susceptibility to several cancers. However, there have been no reports concerning the association between esophageal cancer and L-myc polymorphism. To analyze the distribution of polymorphism in Japanese patients with esophageal cancer, a molecular genotyping method using a polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) was used. Based on an analysis of 65 Japanese patients with esophageal cancer and 107 healthy control subjects, a significant difference was observed in either the distribution of genotypes (P = = = =0.012) or of allele frequencies between the two groups (P = = = =0.004). The relative risk of esophageal cancer for genotypes including the shorter allele was 2.9 compared to the longer allele homozygote. Furthermore, the patients with S-allele had a tendency for poor prognosis among those with three genotypes. A significant difference between the distribution of genotypes and the incidence of lymph node metastasis was found based on the clinicopathological features of the cancers. These results suggest that L-myc polymorphism may be implicated as a genetic trait affecting an individual's susceptibility to esophageal cancer, at least among Japanese patients.

Different Susceptibility of Each L‐myc Genotype to Esophageal Cancer Risk Factors

“…The genotype distribution in cases was not significantly different from that in controls, although the s-allele was more frequent in the patients. Shibuta et al 19) recently reported a significantly different distribution of the genotype and significantly more s-allele in esophageal cancer patients, though the OR for LS/SS genotypes relative to LL genotype was not significant (OR=2.90, 95%CI 0.54-6.54). The allele frequency in this study was not significant (χ 2 =1.65, P=0.200), but both studies showed a similar role of the s-allele.…”

“…Some of these studies showed a positive relationship between L-myc genotypes and susceptibility to some types of cancer, 7,9,19) and metastasis, 6,11,12) but other studies found no relationship between L-myc genotypes and susceptibility to the same and other types of cancer 6,[13][14][15][16][17][18]23) and metastasis. 6,13,15) This suggests that further studies are required to clarify the relationship between L-myc genotypes and susceptibility to cancer.…”

“…19) Since opposite results were reported for the relationship between the susceptibility to some types of cancer and the L-myc polymorphism as described above, further studies are also required on esophageal cancer. In the present study, we assessed the relationship between the L-myc genotype and esophageal cancer risk.…”

“…To date, only one study has been reported on the relationship between susceptibility to esophageal cancer and the L-myc polymorphism, showing that esophageal cancer risk was increased in the SS genotype. 19) Since opposite results were reported for the relationship between the susceptibility to some types of cancer and the L-myc polymorphism as described above, further studies are also required on esophageal cancer. In the present study, we assessed the relationship between the L-myc genotype and esophageal cancer risk.…”

Linkage disequilibrium pattern in the L-myc gene in Italian and Japanese non-small-cell lung-cancer patients

“…5,6 The significant association of L-myc EcoRI polymorphism with tumor prognosis in Asian patients has been confirmed in several laboratories and several tumor types. 3,4,12,13 It is possible that the EcoRI polymorphism is in significant LD with a nearby gene affecting tumor prognosis but that such LD is detectable only in Asians and not in Caucasians. Consistent with this hypothesis, we detected a population-specific allele frequency.…”