Norio Okumura

A functional polymorphism in the epidermal growth factor gene predicts hepatocellular carcinoma risk in Japanese hepatitis C patients

Background A single nucleotide polymorphism (SNP) in the epidermal growth factor (EGF) gene (rs4444903) has been associated with increased risk of cancer, including hepatocellular carcinoma (HCC). The aim of this study was to examine the relationship between the EGF SNP genotype and the development and prognosis of HCC, in a Japanese population. Methods Restriction fragment-length polymorphism was used to determine the presence of the EGF SNP genotype in 498 patients, including 208 patients with HCC. The level of EGF messenger ribonucleic acid (mRNA) expression in cancerous tissues was measured by quantitative reverse transcription polymerase chain reaction. The correlation between the EGF SNP genotype and prognosis was statistically analyzed in the patients with HCC. Results The proportion of the A/A, A/G, and G/G genotypes were 5.3%, 42.8%, and 51.9%, respectively, in the patients with HCC, whereas in those without HCC, they were 8.6%, 35.9%, and 55.5%, respectively, revealing that the odds ratio (OR) of developing HCC was higher in patients with a G allele (OR =1.94, P=0.080 for A/G patients and OR =1.52, P=0.261 for G/G patients, as compared with A/A patients). In particular, when the analysis was limited to the 363 patients with hepatitis C, the OR for developing HCC was 3.54 (P=0.014) for A/G patients and was 2.85 (P=0.042) for G/G patients, as compared with A/A patients. Tumoral EGF mRNA expression in G/G patients was significantly higher than that in A/A patients (P=0.033). No statistically significant differences were observed between the EGF SNP genotype and diseasefree or overall survival. Conclusion The EGF SNP genotype might be associated with a risk for the development of HCC in Japanese patients but not with prognosis. Of note, the association is significantly stronger in patients with hepatitis C, which is the main risk factor for HCC in Japan.

Abstract 3145: Investigation of a functional polymorphism in the epidermal growth factor gene for pathogenesis and prognosis of hepatocellular carcinoma in Japanese patients.

[Introduction] A single nucleotide polymorphism (SNP) in the epidermal growth factor (EGF) gene (rs4444903) has been investigated as a predictor of hepatocellular carcinoma (HCC). Previous reports identified an A to G transition at position 61 in the 5’ untranslated region of the EGF gene and demonstrated that the G/G genotype was associated with an increased risk of developing HCC as compared to the A/G and A/A genotype. Racial differences with respect to the distribution of this SNP have been reported; however, no investigation has examined a Japanese population. [Objectives] To examine the relationship between EGF SNP genotype and the development and prognosis of HCC in a Japanese population.[Methods] Restriction fragment-length polymorphism was used to determine EGF SNP genotype in two hundred and eight patients with HCC, who underwent resection in our department between 1994 and 2010. The level of EGF mRNA expression in cancerous tissues was measured by quantitative reverse transcription-PCR. EGF SNP was also analyzed in three hundred and four patients with either hepatitis, liver cirrhosis, or healthy controls. The correlation between EGF SNP genotype and prognosis was statistically analyzed in patients with HCC. [Results] A/A, A/G, and G/G genotype were 5.3%, 42.8%, and 51.9% in the Japanese patients with HCC. Tumoral EGF mRNA expression in G/G patients was significantly higher than that in A/A patients (P=0.04). A/A, A/G, and G/G genotype were 8.2%, 35.9%, and 55.9% in patients without HCC. Analysis of the distribution of allelic frequencies revealed that the odds ratios of developing HCC were 1.86 (95% CI 0.88-4.12, P=0.23) in A/G patients and 1.44 (95% CI 0.70-3.17, P=0.33) in G/G patients compared with A/A patients. However, when the analysis was limited to patients with hepatitis C, the odds ratio were 3.37 (95% CI 1.20-12.06, P=0.02) in A/G patients, and 2.77 (95% CI 1.10-9.78, P=0.04) in G/G patients, compared with A/A patients. 3) No statistically significant differences were observed between EGF SNP genotype and disease-free and overall survival. [Conclusions] The frequency of the EGF SNP genotype in a Japanese population was characterized by a very low distribution of A/A patients. The EGF 61*G allele was associated with greater EGF mRNA expression in HCC tissue. The EGF SNP genotype was also associated with risk for development of HCC in hepatitis C patients but not with prognosis. Citation Format: Masaya Suenaga, Suguru Yamada, Tsutomu Fujii, Bryan C. Fuchs, Norio Okumura, Goro Nakayama, Shin Takeda, Kenneth K. Tanabe, Yasuhiro Kodera. Investigation of a functional polymorphism in the epidermal growth factor gene for pathogenesis and prognosis of hepatocellular carcinoma in Japanese patients. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3145. doi:10.1158/1538-7445.AM2013-3145

Abstract 3402: Clinical implication of epithelial to mesenchymal transition (EMT) in hepatocellular carcinoma

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL [Background] EMT (epithelial-to-mesenchymal transition) was originally proposed as a process of organogenesis. In recent years, the association between EMT and cancer invasion and metastasis has been advocated and actively investigated in various cancers. In addition, chemoresistance and cancer stemness could be involved in EMT, and the elucidation of this association might contribute to improved outcomes of hepatocellular carcinoma (HCC). We utilized surgical specimens of HCC from our department to examine the clinical implications of EMT. [Methods] One hundred-one patients with hepatocellular carcinoma, who underwent resection in our department between 1994 and 2003 were analyzed. The mRNA expression of E-cadherin and Vimentin were measured by quantitative real-time PCR and EMT status of each patient was determined as follows: Vimentin/E-cadherin < 2 = Epithelial (E), Vimentin/E-cadherin ≤ 2 = Mesenchymal (M). Moreover, transcription factors which are involved in EMT (Twist, Snail, Slug, Zeb-1, and Zeb-2) and also IL-6 and its receptor IL-6R were measured. The correlation between these values and clinicopathological factors and prognosis were analyzed statistically. [Results] 1. AFP values were significantly higher in the epithelial group than in the mesenchymal group (P = 0.029) and PIVKA-II values also tended to be higher in the epithelial group as compared to the mesenchymal group. There was no difference in overall survival, but a significant difference was found in disease-free survival (P = 0.042), which showed that patients with a mesenchymal tumor were more prone to have an earlier recurrence than those with an epithelial tumor. 2. All transcription factors (Twist, Snail, Slug, Zeb-1, and Zeb-2) were more highly expressed in mesenchymal than in epithelial tumors, and in particular, Twist and Zeb-2 were significantly overexpressed (P = 0.0002, P = 0.0017, respectively). Overall survival and disease-free survival of Twist and Zeb-2 expression tumors were examined, but there was no difference between these groups. 3. IL-6 expression was also significantly higher in mesenchymal than in epithelial tumors, but there was no difference in IL-6R expression. [Discussion] Analysis of EMT status in HCC has been performed in the past, but the majority of these studies were done in vitro. Our study using resected surgical specimens suggest that EMT could be involved in cancer invasion and metastasis at the clinical level. In particular, Twist and Zeb-2 might be important for inducing EMT in HCC and patients with mesenchymal tumors are more prone to have early recurrence or metastases after resection. In addition, IL-6 might be an important factor for HCC EMT and could be a potential therapeutic target. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3402. doi:1538-7445.AM2012-3402