Yutaka Natsumeda

SNP (–617C>A) in ARE-Like Loci of the NRF2 Gene: A New Biomarker for Prognosis of Lung Adenocarcinoma in Japanese Non-Smoking Women

Purpose The transcription factor NRF2 plays a pivotal role in protecting normal cells from external toxic challenges and oxidative stress, whereas it can also endow cancer cells resistance to anticancer drugs. At present little information is available about the genetic polymorphisms of the NRF2 gene and their clinical relevance. We aimed to investigate the single nucleotide polymorphisms in the NRF2 gene as a prognostic biomarker in lung cancer. Experimental Design We prepared genomic DNA samples from 387 Japanese patients with primary lung cancer and detected SNP (c.–617C>A; rs6721961) in the ARE-like loci of the human NRF2 gene by the rapid genetic testing method we developed in this study. We then analyzed the association between the SNP in the NRF2 gene and patients’ overall survival. Results Patients harboring wild-type (WT) homozygous (c.–617C/C), SNP heterozygous (c.–617C/A), and SNP homozygous (c.–617A/A) alleles numbered 216 (55.8%), 147 (38.0%), and 24 (6.2%), respectively. Multivariate logistic regression models revealed that SNP homozygote (c.–617A/A) was significantly related to gender. Its frequency was four-fold higher in female patients than in males (10.8% female vs 2.7% male) and was associated with female non-smokers with adenocarcinoma. Interestingly, lung cancer patients carrying NRF2 SNP homozygous alleles (c.–617A/A) and the 309T (WT) allele in the MDM2 gene exhibited remarkable survival over 1,700 days after surgical operation (log-rank pu200a=u200a0.021). Conclusion SNP homozygous (c.–617A/A) alleles in the NRF2 gene are associated with female non-smokers with adenocarcinoma and regarded as a prognostic biomarker for assessing overall survival of patients with lung adenocarcinoma.

Capsule-endoscopic findings of ulcerative colitis patients.

Background/Aims: Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by diffuse mucosal inflammation, traditionally regarded as being limited to the colorectum. Although several gastroduodenal lesions have also been reported recently in cases of UC, in general, small-bowel lesions in UC are believed to be extremely rare. The aim of this study was to examine the small bowel by capsule endoscopy in patients with UC. Methods: The study was conducted in 23 well-documented UC patients and 23 control volunteers. The frequency of small-bowel lesions, the number of small-bowel lesions per patient and the capsule endoscopy score were comparatively evaluated between the two groups. Results: Of the 23 UC patients, 13 (57%) showed small-bowel lesions, and 8 (35%) had erosions. There were significant differences in the frequency of the small-bowel lesions (p < 0.001) and erosions (p = 0.009) between the two groups. The capsule endoscopy score was correlated with the UC disease activity index (r = 0.718, p < 0.001). Conclusions: This is the first capsule-endoscopic study conducted to examine the small-bowel involvement in UC patients as compared with the healthy volunteers. It was concluded that UC, a chronic inflammatory bowel disease, can also involve the small bowel.

Eicosapentaenoic acid (EPA) efficacy for colorectal aberrant crypt foci (ACF): a double-blind randomized controlled trial

BackgroundColorectal cancer (CRC) is one of the most commonly occurring neoplasms and a leading cause of cancer death worldwide, and new preventive strategies are needed to lower the burden of this disease. Eicosapentaenoic acid (EPA), the omega-3 polyunsaturated fatty acid that is widely used in the treatment of hyperlipidemia and prevention of cardiovascular disease, has recently been suggested to have a suppressive effect on tumorigenesis and cancer cell growth. In CRC chemoprevention trials, in general, the incidence of polyps or of the cancer itself is set as the study endpoint. Although the incidence rate of CRC would be the most reliable endpoint, use of this endpoint would be unsuitable for chemoprevention trials, because of the relatively low occurrence rate of CRC in the general population and the long-term observation period that it would necessitate. Moreover, there is an ethical problem in conducting long-term trials to determine whether a test drug might be effective or harmful. Aberrant crypt foci (ACF), defined as lesions containing crypts that are larger in diameter and stain more darkly with methylene blue than normal crypts, are considered as a reliable surrogate biomarker of CRC. Thus, we devised a prospective randomized controlled trial as a preliminary study prior to a CRC chemoprevention trial to evaluate the chemopreventive effect of EPA against colorectal ACF formation and the safety of this drug, in patients scheduled for polypectomy.MethodsThis study is a multicenter, double-blind, placebo-controlled, randomized controlled trial to be conducted in patients with both colorectal ACF and colorectal polyps scheduled for polypectomy. Eligible patients shall be recruited for the study and the number of ACF in the rectum counted at the baseline colonoscopy. Then, the participants shall be allocated randomly to either one of two groups, the EPA group and the placebo group. Patients in the EPA group shall receive oral 900-mg EPA capsules thrice daily (total daily dose, 2.7 g per day), and those in the placebo group shall receive oral placebo capsules thrice daily. After one month’s treatment with EPA/placebo, colonoscopic examination and polypectomy will be performed to evaluate the formation of ACF, and the cell-proliferative activity and cell-apoptotic activity in normal colorectal mucosa and colorectal polyps.DiscussionThis is the first study proposed to explore the effect of EPA against colorectal ACF formation in humans.This trial has been registered in the University hospital Medical Information Network (UMIN) Clinical Trials Registry as UMIN000008172.

Hypoxanthine-guanine phosphoribosyltransferase from rat liver. Effects of magnesium 5-phosphoribosly 1-pyrophosphate on the chemical modification and stability of the enzyme

Abstract 1. 1. The homogeneously purified hypoxanthine-guanine phosphoribosyltransferase (IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8) from rat liver was strongly inactivated by the sulfhydryl reagents, p -chloromercuribenzoate and 5,5′-dithiobis(2-nitrobenzoic acid). The addition of magnesium 5-phosphoribosyl 1-pyrophosphate, the substrate, almost completely protected the enzyme and magnesium pyrophosphate, the product, partially protected the enzyme from the inactivation by SH reagents. 2. 2. The time course of 2,4,6-trinitrobenzenesulfonic acid-inactivation of hypoxanthine-guanine phosphoribosyltransferase revealed that the enzyme activity was initially increased and then decreased. The enzyme was also completely protected against the 2,4,6-trinitrobenzenesulfonic acid-inactivation in the presence of either magnesium 5-phosphoribosyl 1-pyrophosphate or magnesium pyrophosphate. 3. 3. Hypoxanthine-guanine phosphoribosyltransferase was substantially protected against heat- and trypsin-inactivation by the addition of phosphoribosylpyrophosphate plus MgCl 2 . The sucrose density gradient centrifugation showed that phosphoribosylpyrophosphate yielded the enzyme species with a larger s value than that of control. 4. 4. These results suggest that the thiol and/or amino groups of the enzyme could be responsible for the binding of 1-magnesium pyrophosphoryl group of magnesium phosphoribosylpyrophosphate, and the binding of magnesium phosphoribosylpyrophosphate induces the more rigid conformation of the enzyme molecule somewhat different from those caused by the other substrates, products and inhibitors.

Conditional knockout of the leptin receptor in the colonic epithelium revealed the local effects of leptin receptor signaling in the progression of colonic tumors in mice.

Leptin, secreted by the adipose tissue and known to be related to obesity, is considered to be involved in the onset and progression of colorectal cancer. However, the exact role of leptin in colorectal carcinogenesis is still unclear, as several controversial reports have been published on the various systemic effects of leptin. The aim of this study was to clarify the local and precise roles of leptin receptor (LEPR)-mediated signaling in colonic carcinogenesis using intestinal epithelium-specific LEPRb conditional knockout (cKO) mice. We produced and used colonic epithelium-specific LEPRb cKO mice to investigate the carcinogen-induced formation of aberrant crypt foci (ACF) and tumors in the colon, using their littermates as control. There were no differences in the body weight or systemic condition between the control and cKO mice. The tumor sizes and number of large-sized tumors were significantly lower in the cKO mice as compared with those in the control mice. On the other hand, there was no significant difference in the proliferative activity of the normal colonic epithelial cells or ACF formation between the control and cKO mice. In the control mice, marked increase of the LEPRb expression level was observed in the colonic tumors as compared with that in the normal epithelium; furthermore, signal transducer and activator of transcription (STAT3) was activated in the tumor cells. These findings suggest that STAT3 is one of the important molecules downstream of LEPRb, and LEPRb/STAT3 signaling controls tumor cell proliferation. We demonstrated the importance of local/regional LEPR-mediated signaling in colorectal carcinogenesis.

Recent Trends in Colonic Diverticulosis in Yokohama City: A Possibility of Changing to a More Western Profile

OBJECTIVEnRight-sided type colonic diverticulosis has been predominant in Japan, in contrast to European counties where the left-sided type is predominant. Considering the recent change in the dietary habits of Japanese people to a more Western diet in urban areas of Japan, the features of colonic diverticulosis may also change to reflect a more Western type. Therefore, we attempted to clarify the current situation.nnnMETHODSnA total of 435 consecutive outpatients who agreed to a barium enema and complete examination were enrolled in this study.nnnRESULTSn113 patients (26.0%) revealed colon diverticulosis; 50.4% of the patients had more than ten diverticula. The percentage of man with ten or more diverticula (67.4%) was significantly higher than that of women patients (40.0%, p<0.01). Among the 88 patients who had four or more diverticula, 39 patients (44.3%) were right-side dominant, 27 (30.7%) left-side dominant and 22 (25.0%) were both-sides. Thirteen (68.4%) of the 19 patients who had more than 30 diverticula were left-side dominant.nnnCONCLUSIONnThe clinical features of colon diverticulosis in the patients living in Yokohama may be changing to reflect a more Western type, in particular decreased right-side dominance, increases in the left-side and both-sides dominant patients, and the emergence of patients with crowded diverticula in the left-side colon was observed.

Abstract 4336: Direct genotyping of CYP2A6 whole gene deletion: A new biomarker for prognosis of lung adenocarcinoma in Japanese smoking male

Purpose: Cytochrome P450 (CYP2A6) is known as an enzyme responsible for the metabolism of activation of tobacco-specific nitrosamines to their ultimate carcinogenic forms and metabolism of nicotine. We here report that the genetic polymorphisms of human CYP2A6*4 is associated with primary lung cancer and their overall survival. Experimental Design: We prepared genomic DNA samples from 387 Japanese patients with primary lung cancer and the genetic polymorphisms of human CYP2A6*4 (whole gene deletion) by the rapid genetic testing method we developed in this study. We analyzed the association between the CYP2A6*4 gene, NRF2 gene and overall survival. Results: Patients harboring wild-type CYP2A6*1 and whole gene deletion CYP2A6*4/*4 numbered 380 (98.2%) and 7 (1.8%), respectively. Its frequency was four-fold higher in male patients than in female (P = 0.038).Multivariate logistic regression models revealed that the genetic polymorphisms of human CYP2A6*4 were significantly related to gender and smoking behavior. Interestingly, lung cancer patients carrying CYP2A6*4/*4 (whole gene deletion), the NRF2 SNP heterozygous (c.-617C/A) and wild-type homozygous (c.-617C/C) exhibited remarkable survival over 1,500 days after surgical operation. Conclusion: CYP2A6*4/*4 whole gene is considered to be a prognostic biomarker for assessing both the gender-related risk of lung adenocarcinoma in the smoking sub-population and their overall survival. Citation Format: Yasuko Okano, Yasushi Ichikawa, Yohei Miyagi, Takashi Chishima, Yutaka Natsumeda. Direct genotyping of CYP2A6 whole gene deletion: A new biomarker for prognosis of lung adenocarcinoma in Japanese smoking male. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4336. doi:10.1158/1538-7445.AM2015-4336

Abstract 1857: Prognostic biomarker for SNP (-617C-A) in ARE-like loci of the NRF2 gene in lung adenocarcinoma

Purpose: We here report that SNP (c.-617C>A; rs6721961) in the ARE-like region of NRF2 gene is associated with Japanese non-smoking female patients with adenocarcinoma and their overall survival. Experimental Design: We prepared genomic DNA samples from 387 Japanese patients with primary lung cancer and detected a SNP (-617C>A) in NRF2 gene by the rapid genetic testing method we developed in this study. We analyzed the association between the SNP in the NRF2 gene and overall survival. Results:Patients harboring wild-type -617C/C, -617C/A, and -617A/A alleles numbered 216 (55.8%), 147 (38.0%), and 24 (6.2%), respectively. Multivariate logistic regression models revealed that SNP homozygote (-617A/A) was significantly related to gender. Its frequency was four-fold higher in female patients than in males (10.8% female vs 2.7% male) and was associated with female non-smokers with adenocarcinoma. Interestingly, lung cancer patients carrying the SNP homozygous alleles (-617A/A) and the 309T (WT) allele in the MDM2 gene exhibited remarkable survival over 1,700 days after surgical operation (log-rank p=0.021). Conclusion: SNP homozygous (-617 A/A) alleles in the NRF2 gene are associated with female non-smokers with adenocarcinoma and regarded as a prognostic biomarker for assessing overall survival of patients with lung adenocarcinoma. Citation Format: Yasuko Okano, Yasushi Ichikawa, Yohei Miyagi, Keiichi Kondo, Yutaka Natsumeda. Prognostic biomarker for SNP (-617C-A) in ARE-like loci of the NRF2 gene in lung adenocarcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1857. doi:10.1158/1538-7445.AM2014-1857

Abstract 2361: SNP (-617G>A) in ARE-like loci of the NRF2 gene: a new biomarker for prognosis of lung adenocarcinoma.

Purpose: Accumulating evidence suggests nuclear factor (erythroid-derived 2)-like 2 (NRF2) plays an important role as cellular defense, tumor suppression, and oncogenesis. However, little information is available as to the genetic polymorohisms of the NRF2 gene and their clinical relevance. We aimed to validate the NRF2 gene as a prognostic biomarker in lung cancer. Experimental Design: We prepared genomic DNA from 392 Japanese patients with primary lung cancer and detected a SNP (c.-617C>A) in the ARE-like loci of the human NRF2 gene by the rapid genetic testing method we developed in this study. We analyzed an association between the NRF2 gene and overall survival. Results: We detected homozygous (A/A) and heterozygous (C/A) alleles with the SNP (c.-617C>A) in 24 (6.2%) and 147 (38.0%) patients, respectively. The frequency of the homozygote (A/A) was four-fold higher in females than in males (11.0% versus 2.7%). Multivariate logistic regression models including standard lung cancer factors revealed that the homozygous alleles (c.-617A/A) were significantly related to gender. Interestingly, lung cancer patients carrying the homozygous alleles (c.-617A/A) exhibited remarkable survival over 1,700 days after surgical operation (log-rank p=0.021). Conclusion: The homozygous allele (c.-617A/A) in the NRF2 gene is considered to be a prognostic biomarker for assessing both the gender-related risk of lung adenocarcinoma in the non-smoking sub-population and their overall survival. Citation Format: Yasuko Okano, Yasushi Ichikawa, Yohei Miyagi, Yutaka Natsumeda, Toshihisa Ishikawa. SNP (-617G>A) in ARE-like loci of the NRF2 gene: a new biomarker for prognosis of lung adenocarcinoma. [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 2361. doi:10.1158/1538-7445.AM2013-2361