Search

Background CDO1 is a presumed tumor suppressor gene in human cancers, the expression of which is silenced by promoter DNA methylation. Moreover, CDO1 harbors functionally oncogenic aspects through modification of mitochondrial membrane potential. We recently proposed that this oncogenic feature allows for the prediction of the efficacy of postoperative chemotherapy in colon cancer. The present study aims to elucidate the efficacy of prediction of success of postoperative chemotherapy in advanced gastric cancer to improve the treatment strategy of patients. Materials and methods Forced expression of CDO1 in gastric cancer cell lines was assessed using the JC-1 assay. Promoter DNA methylation was investigated in quantitative TaqMan methylation–specific polymerase chain reaction in 321 pathological stage II/III advanced gastric cancer cases treated by curative gastrectomy with or without postoperative chemotherapy. Results (1) Forced expression of CDO1 led to increased mitochondrial membrane potential, accompanied by augmented survival in gastric cancer cells under anaerobic conditions. These results suggest that CDO1-expressing cancer cells survive more easily in anaerobic lesions which are inaccessible to anticancer drugs. (2) Intriguingly, in cases with the highest CDO1 methylation (ranging from 15% to 40%), patients with postoperative chemotherapy showed significantly better survival than those with no postoperative chemotherapy. (3) A robust prognostic difference was observed that was explained by differential recurrences of distant metastasis (P = 0.0031), followed by lymph node (P = 0.0142) and peritoneal dissemination (P = 0.0472). Conclusions The oncogenic aspects of CDO1 can be of use to determine patients with gastric cancer who will likely respond to treatment of invisible systemic dissemination by postoperative adjuvant chemotherapy.

PurposeThe benefits of robot-assisted laparoscopic surgery (RALS) for rectal cancer remain controversial. Only a few studies have evaluated the safety and feasibility of RALS following neoadjuvant chemoradiotherapy (NCRT). This study aimed to compare the short-term outcomes of RALS versus conventional laparoscopic surgery (CLS) after NCRT for rectal cancer.MethodsPropensity score matching of 111 consecutive patients who underwent RALS or CLS after NCRT for rectal adenocarcinoma between February 2014 and February 2022 was performed. Among them, 60 matched patients were enrolled and their short-term outcomes were compared.ResultsAlthough operative time, conversion rate to open laparotomy and blood loss were comparable, the incidence of postoperative complications, including anastomotic leakage, was significantly lower, urinary retention tended to be lower, and the days to soft diet intake and postoperative hospital stay were significantly shorter in the RALS than the CLS group. No postoperative mortality was observed in either group, and there were no significant differences in terms of resection margins and number of lymph nodes dissected.ConclusionsRALS after NCRT for rectal cancer is safe and technically feasible, and has acceptable short-term outcomes. Further studies are required for validation of the long-term oncological outcomes.

The advantages of robotic-assisted laparoscopic surgery (RALS) for rectal cancer remain controversial. This study clarified and compared the short-term outcomes of RALS for rectal cancer with those of conventional laparoscopic surgery (CLS).The records of 303 consecutive patients who underwent RALS or CLS for rectal adenocarcinoma between November 2016 and November 2021 were analyzed using propensity score-matched analysis. After matching, 188 patients were enrolled in our study to compare short-term outcomes, such as operative results, postoperative complications, and pathological findings, in each group.After matching, baseline characteristics were comparable between groups. Although operative time in the RALS group was significantly longer than in the CLS group (p 0.0001), the conversion rate to open laparotomy and the postoperative complication rate in the RALS group were significantly lower than in the CLS group (p = 0.0240 and p = 0.0109, respectively). Blood loss was comparable between groups. In the RALS group, postoperative hospital stay and days to soft diet were significantly shorter than those in the CLS group (p = 0.0464 and p 0.0001, respectively). No postoperative mortality was observed in either group and significant differences were observed in resection margins and number of lymph nodes harvested.Robotic-assisted laparoscopic surgery for rectal cancer was safe, technically feasible, and had acceptable short-term outcomes. Further studies are required to validate long-term oncological outcomes.

Myopenia and myosteatosis are reported to be long-term prognostic factors in patients with colorectal cancer (CRC). However, the established parameters are unsuitable for the Japanese population because their body composition is different from that of the Western population.We aimed to elucidate the effect of skeletal muscle changes among Japanese adults, measured using preoperative computed tomography (CT) as a prognostic factor in patients with stage III CRC.We retrospectively analyzed 341 patients diagnosed with stage III CRC. The cross-sectional area (skeletal muscle index: SMI) and mean radiodensity of skeletal muscle (skeletal muscle radiodensity: SMR) were measured using preoperative CT. The optimal sex-specific cutoff value, which was used to divide the patients according to the risk of recurrence, was set for SMI and SMR. Univariate and multivariate analysis were performed to determine the prognostic factors for recurrence-free survival (RFS).The cutoff values of SMI for men and women were set as 48.5 and 41.4, respectively, and those of SMR were 35.0 and 21.7, respectively. Univariate analysis identified low SMI and SMR in men and low SMR in women as the worst prognostic factors for RFS. Multivariate analysis identified low SMI in men and low SMR in women as independent poor prognostic factors for RFS (hazard ratio [HR] = 1.87, 95% confidence interval [CI], 1.08-3.47,Low SMI in men and low SMR in women were the independent prognostic factors for patients with stage III CRC.

OBP-801 is a novel histone deacetylase inhibitor being developed as an anticancer drug. In this study, we explored genes to predict drug resistance in human cancer. OBP-801 resistance was assessed in 37 strains of human cancer cell lines. Expression microarrays harboring 54,675 genes were used to focus on candidate genes, which were validated for both functional and clinical relevance in esophageal squamous cell carcinoma (ESCC). OBP-801 is sensitive to esophageal, gastric, and thyroid cancer, and resistant to some esophageal and colorectal cancers. We therefore used ESCC to explore genes. Comprehensive exploration focused on ΔNp63/SOX2, which were both genetically and epigenetically overexpressed in ESCC. Genomic amplifications of ΔNp63/SOX2 were tightly correlated each other (r = 0.81). Importantly, genomic amplification of ΔNp63/SOX2 in the resected tumors after neoadjuvant chemotherapy was significantly associated with histological grade of response (G1). Forced expression of either of these two genes did not induce each other, suggesting that their functional relevances were independent and showed robust drug resistance in OBP-801, as well as 5-fluorouracil. Furthermore, ΔNp63 could exert a potent oncogenic potential. RNA interference of ΔNp63 supported its oncological properties, as well as drug resistance. Comprehensive exploration of genes involved in anticancer drug residence could identify critical oncogenes of ΔNp63/SOX2 that would predict chemotherapy response in ESCC.

This study aimed to explore the predicting factor of the poor prognosis of stage III colon cancer. Adjuvant chemotherapy for stage III colon cancer has become popular. However, the choice of the optimal adjuvant chemotherapy regimen still remains unclear. A total of 135 patients with stage III colon cancer, treated with postoperative adjuvant chemotherapy from January 2007 to December 2012 at the Kitasato University East Hospital, were reviewed retrospectively in terms of clinicopathologic characteristics associated with survival and recurrence (median observation: 61 months). We used a multivariate Cox hazards model to identify independent prognostic factors in stage III colon cancer. Of the 135 patients, 38 had recurrence. Five-year overall survival was 83.9%, while 3-year recurrence-free survival was 72.8%. Oxaliplatin-containing adjuvant chemotherapy was almost exclusively applied to stage IIIB colon cancer. Univariate analysis of the negative prognostic factors were N2 (P = 0.0004); operation time (P = 0.0346); tumor size (P = 0.0092); depth of invasion (P = 0.005); histology (P = 0.0403); infiltration type (P < 0.0001); lymphatic permeation (ly3, P = 0.0001); and vascular permeation (v3, P = 0.0005). On multivariate analysis, the independent prognostic factors for relapse-free survival were v3 (P = 0.032) and N2 (P = 0.0216). Combination of the prognostic factors clearly stratified prognosis of stage III colon cancer patients, and those with either factor positive had a poor prognosis despite administration of adjuvant chemotherapy. Both v3 and pN2 may be critical prognostic factors in stage III colon cancer with adjuvant chemotherapy. This information would elucidate areas of concern in the present therapeutic strategy in stage III colon cancer.

DNA markers for pancreatic ductal adenocarcinoma (PDAC) are urgently needed for detection of minimally invasive disease. The epigenetic relevance of the cysteine dioxygenase 1 gene (CDO1) has been never investigated in PDAC. Three studies, including cellular experiments, tissue validation, and pilot testing for pancreatic cytology, were carried out. Promoter DNA methylation value (MV) of CDO1 was quantified by quantitative methylation‐specific PCR. CDO1 expression was consistent with its promoter DNA methylation in 7 PDAC cell lines. In 160 retrospectively collected primary PDAC tumor tissues, MV was significantly higher compared to the corresponding noncancerous pancreas (area under the receiver operating characteristic curve [AUC] = 0.97, P

// Keita Kojima 1 , Naoko Minatani 1 , Hideki Ushiku 1 , Satoru Ishii 1 , Toshimichi Tanaka 1 , Keigo Yokoi 1 , Nobuyuki Nishizawa 1 , Yosuke Ooizumi 1 , Kazuharu Igarashi 1 , Kei Hosoda 1 , Hiromitsu Moriya 1 , Hiroaki Mieno 1 , Masahiko Watanabe 1 and Keishi Yamashita 1 , 2 1 Department of Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0329, Japan 2 Division of Advanced Surgical Oncology, Research and Development Center for New Frontier, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0329, Japan Correspondence to: Keishi Yamashita, email: keishi23@med.kitasato-u.ac.jp Keywords: remnant gastric cancer; cysteine dioxygenase 1 (CDO1); homeodomain-only protein X (HOPX); Reprimo; E-cadherin Received: September 17, 2018 Accepted: January 19, 2019 Published: March 29, 2019 ABSTRACT Background: Early detection of remnant gastric cancer (RGC) is required to reduce the risk of death, but long-term endoscopic surveillance is difficult after gastrectomy. In this study, data for the methylation status of 4 methylation genes ( CDO1, HOPX, Reprimo, and E-cadherin ) to predict the onset of RGC are presented. Results: The 4 genes showed hypermethylation in RGC tumors in contrast to the corresponding non-cancerous mucosa tissues. The methylation level in the non-cancerous mucosa tissues of the initial surgery was obviously high in initial malignant disease for CDO1 ( P = 0.0001), while in initial benign one for E-cadherin ( P = 0.003). Promoter DNA methylation status in the remnant non-cancerous mucosa tissues together with the basic clinical data in turn predicted either initial malignant disease or initial benign disease with a high AUC score of 0.94, suggesting that methylation events are differentially recognized between the initial malignant and benign disease. We then finally confirmed that 4 genes hypermethylation of the non-cancerous tissues by biopsy prior to onset of RGC could predict terms until RGC occurred ( P < 0.0001). Methods: A total of 58 RGC patients were used to establish the model. The 4 genes promoter methylation were analyzed for DNA obtained from the patient’s specimens using quantitative methylation specific polymerase chain reaction. Conclusions: This risk model would help provide guidance for endoscopic surveillance plan of RGC after gastrectomy.

Cysteine dioxygenase type 1 (CDO1) acts as a tumor suppressor gene, and its expression is regulated by promoter DNA methylation in human cancer. The metabolic product mediated by CDO1 enzyme increases mitochondrial membrane potential (MMP), putatively representing chemoresistance. The aim of this study is to investigate the functional relevance of CDO1 gene in colon cancer with chemotherapy. We investigated 170 stage III colon cancer patients for CDO1 methylation by using quantitative methylation-specific polymerase chain reaction (PCR). To elucidate the functional role of CDO1 gene in colorectal cancer (CRC) biology, we established cell lines that stably express CDO1 gene and evaluated chemosensitivity, MMP, and tolerability assay including anaerobic environment. Hypermethylation of CDO1 gene was an independent prognostic factor for stage III colon cancer on multivariate prognostic analysis. Surprisingly, patients with CDO1 hypermethylation exhibited better prognosis than those with CDO1 hypomethylation in stage III colon cancer with postoperative chemotherapy (P = 0.03); however, a similar finding was not seen in those without postoperative chemotherapy. In some CRC cell lines, forced expression of CDO1 gene increased MMP accompanied by chemoresistance and/or tolerance under hypoxia. CDO1 methylation may be a useful biomarker to increase the number of stage III colon cancer patients who can be saved by adjuvant therapy. Such clinical relevance may represent the functionally oncogenic property of CDO1 gene through MMP activity.

Introduction Despite technical improvements in laparoscopic gastrectomy, gastric stasis is still a serious problem in laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG). The aim of this study was to investigate the factors that might cause gastric stasis in LAPPG. Methods From April 2004 through November 2012, 85 patients with cT1N0 middle-third gastric cancer who underwent LAPPG at Kitasato University Hospital; these patients were included in the present study. Infra-pyloric vein (IPV)-preserving LAPPG was performed in 41 patients. We compared the rate of gastric stasis in the IPV-preserving and the IPV-non-preserving groups, and analyzed the clinicopathological factors that might have caused gastric stasis. Results We did not demonstrate that preservation of the IPV could prevent gastric stasis in the early and late postoperative periods. Symptoms of gastric stasis were most frequently recognized 1 year after surgery. A significantly higher proportion of preoperative ASA class 2 patients had gastric stasis than did not (80.0% [12/15] vs 48.6% [34/70], P=0.02). Among the ASA class 2 patients, a significantly greater proportion of those with depressed activities of daily living than those with normal activities of daily living had gastric stasis (66.7% [4/6] vs 20.0% [8/40], P = 0.015). Conclusions The clinical significance of the IPV preservation in LAPPG could not be demonstrated. LAPPG should be performed for ASA class 1 patients or those with maintained preoperative activities of daily living.

// Satoru Ishii 1 , Keishi Yamashita 1 , Hiroki Harada 1 , Hideki Ushiku 2 , Toshimichi Tanaka 1 , Nobuyuki Nishizawa 1 , Keigo Yokoi 1 , Marie Washio 1 , Akira Ema 1 , Hiroaki Mieno 1 , Hiromitsu Moriya 1 , Kei Hosoda 1 , Mina Waraya 3 , Hiroshi Katoh 1 and Masahiko Watanabe 1 1 Department of Surgery, Kitasato University School of Medicine, Sagamihara, Japan 2 Department of Surgery, Kitasato University Medical Center, Saitama, Japan 3 Department of Surgery, Sagamino Hospital, Sagamihara, Japan Correspondence to: Masahiko Watanabe, email: gekaw@med.kitasato-u.ac.jp Keywords: gastric cancer, lymph node ratio, H19, PEG10, IGF2BP3 Received: February 15, 2017 Accepted: June 06, 2017 Published: August 05, 2017 ABSTRACT We previously demonstrated that the lymph node ratio (LNR) is a prognostic factor associated with EGFR expression, among first priority genes amplified or overexpressed in cancer. Here, we investigated the associations between high LNR and second, third, and fourth priority genes. We performed mRNA expression microarray analysis of tumor tissue from patients with stage III gastric cancer and high or low LNRs. Candidate high LNR-associated genes were further evaluated in 39 patients with stage III gastric cancer. The functional relevance of these genes was evaluated in gastric cancer cell lines. We focused on five genes: H19 , PEG10 , IGF2BP3 , CD177, and PGA3 . H19 and PEG10 were confirmed as high LNR-associated genes. H19 , PEG10 , and IGF2BP3 were found to promote each other’s expression. Knocking down H19 or PEG10 using RNAi decreased cell proliferation, invasion, anchorage-independent growth, and chemoresistance. These genes had a mutual relationship in MKN7 cells. H19 knockdown decreased expression of epithelial-mesenchymal transition-associated genes in MKN74 cells to suppress transformation. Thus, H19 promotes epithelial-mesenchymal transition in gastric cancer and is a potential therapeutic target.

Minimal residual disease of the peritoneum is challenging for early cancer detection in gastric cancer (GC). Utility of PCR amplification of cancer-derived DNA has been considered feasible due to its molecular stability, however such markers have never been available in GC clinics. We recently discovered cancer-specific methylation of CDO1 gene in GC, and investigated the clinical potential to detect the minimal residual disease. One hundred and two GC patients were investigated for peritoneal fluid cytology test (CY), and detection level of the promoter DNA methylation of CDO1 gene was assessed by quantitative methylation specific PCR (Q-MSP) in the sediments (DNA CY). (1) CY1 was pathologically confirmed in 8 cases, while DNA CY1 was detected in 18 cases. All 8 CY1 were DNA CY1. (2) DNA CY1 was recognized in 14.3, 25.0, 20.0, and 42.9%, in macroscopic Type II, small type III, large type III, and type IV, respectively, while it was not recognized in Type 0/I/V. (3) DNA CY1 was prognostic relevance in gastric cancer (p = 0.0004), and its significance was robust among Type III/IV gastric cancer (p = 0.006 for overall survival and p = 0.0006 for peritoneal recurrence free survival). (4) The peritoneal recurrence was hardly seen in GC patients with potent perioperative chemotherapy among those with DNA CY1. DNA CY1 detected by Q-MSP for CDO1 gene promoter DNA methylation has a great potential to detect minimal residual disease of the peritoneum in GC clinics as a novel DNA marker.

We previously reported that the dissected pancreatic tissue margin (DPM) and the preoperative serum level of carbohydrate antigen 19-9 (preCA19-9) were independent prognostic factors in pancreatic ductal adenocarcinoma (PDAC). In the current study, the prognostic relevance of these factors, including their molecular associations, were validated. A total of 161 patients with PDAC underwent a pancreatectomy between 1986 and 2013, and a multivariate Cox proportional hazards model and a propensity score-based model validated the prognostic importance of DPM. The prognostic factors were compared with the mutation profiles of the K-ras and TP53 genes. Univariate prognostic analysis of disease-specific survival (DSS) demonstrated that DPM (P

We have identified homeobox-only protein (HOPX) as a tumor suppressor gene in various human cancer, and its expression was reduced by promoter DNA hypermethylation. Homeobox-only protein is strongly expressed on pancreatic islet cells; however, clinical relevance of HOPX expression has remained elusive in pancreatic neuroendocrine tumor (pNET).We investigated 36 patients with pNET who undertook surgical resection between 1988 and 2012 for HOPX expression and DNA methylation to reveal its clinical significance.(1) Homeobox-only protein is strongly expressed on pancreatic islet cells by immunohistochemistry (IHC). Homeobox-only protein expression was recognized on pNET tumor cells for 1+ in 15, for 2+ in 16, and for 3+ in 5. (2) Homeobox-only protein IHC expression was significantly associated with prognosis (P = 0.03), and survival rate was 37.5%, 70.3%, and 100% in HOPX 1+, 2+, and 3+, respectively. (3) Promoter DNA methylation was quantitatively assessed, and HOPX hypermethylation is found in 6.3%, 11.8%, and 66.7% of G1/G2/G3 pNET, respectively (P = 0.02). (4) Multivariate Cox proportional hazards model identified HOPX IHC expression and HOPX promoter DNA hypermethylation as independent prognostic factors in pNET.Homeobox-only protein expression is a critical prognostic indicator of pNET, and its regulation may be made through promoter DNA methylation.

The PRL-3 gene is involved in the liver metastasis of colorectal cancer (CRC) and oncogene addiction to anticancer therapy. In the present study genomic gains in PRL-3 and its pathway genes, c-myc and EGFR, were investigated in order to determine their clinical relevance during metastatic formation in primary CRC and corresponding liver metastases. The genomic gain statuses of PRL-3, EGFR, and c-myc were investigated using quantitative polymerase chain reaction (qPCR) analysis in 35 samples of CRC and corresponding liver metastases. In the primary CRC specimens, genomic gains in PRL-3, c-myc, and EGFR were observed in 4, 4, and 13 cases, respectively. A genomic gain in one gene was observed in 18 cases, and these genomic gains were mutually exclusive. In the liver metastasis specimens, genomic gains were observed in 14, 8, and 13 cases, respectively. The copy numbers of PRL-3 and c-myc were significantly higher in the liver metastases than in the primary CRC specimens (P=0.03, P=0.009, respectively). A genomic gain in PRL-3 was the most frequent gain in the liver metastases (P=0.004) and was partially redundant with a c-myc genomic gain. EGFR genomic gains were consistent between the primary CRC and the liver metastases (P=0.0000008). In addition, a genomic gain in any of the 3 genes was observed in 23 cases (66%). Among the clinicopathological factors that were assessed, an EGFR genomic gain was significantly associated with tumour size in the primary CRC and the liver metastases (P=0.04). A c-myc genomic gain was also significantly associated with the v factor of the primary tumours in the liver metastases (P

Despite technical improvements in laparoscopic gastrectomy, gastric stasis is still a serious problem in laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG). The aim of this study was to investigate the factors that might cause gastric stasis in LAPPG.From April 2004 through November 2012, 85 patients with cT1N0 middle-third gastric cancer who underwent LAPPG at Kitasato University Hospital; these patients were included in the present study. Infra-pyloric vein (IPV)-preserving LAPPG was performed in 41 patients. We compared the rate of gastric stasis in the IPV-preserving and the IPV-non-preserving groups, and analyzed the clinicopathological factors that might have caused gastric stasis.We did not demonstrate that preservation of the IPV could prevent gastric stasis in the early and late postoperative periods. Symptoms of gastric stasis were most frequently recognized 1 year after surgery. A significantly higher proportion of preoperative ASA class 2 patients had gastric stasis than did not (80.0% [12/15] vs 48.6% [34/70], P=0.02). Among the ASA class 2 patients, a significantly greater proportion of those with depressed activities of daily living than those with normal activities of daily living had gastric stasis (66.7% [4/6] vs 20.0% [8/40], P = 0.015).The clinical significance of the IPV preservation in LAPPG could not be demonstrated. LAPPG should be performed for ASA class 1 patients or those with maintained preoperative activities of daily living.

Methylation of cysteine dioxygenase type 1 (CDO1) gene, a tumor suppressor gene, has been studied in various cancers; however, there is no information regarding Barrett esophagus cancer. In this study, the clinical significance of CDO1 methylation in Barrett esophagus adenocarcinoma (BEA) was clarified. CDO1 gene promoter methylation was analyzed for DNA from the patient's specimens using quantitative methylation-specific polymerase chain reaction. Thirty-eight BEA patients who underwent resection were identified between 2000 and 2014. Hypermethylation of CDO1 gene was demonstrated to be frequently recognized even at early stage in BEA by quantitative methylation-specific polymerase chain reaction. In BEA, there is a robust prognostic difference between stage I and stage II/III/IV with regard to 5-year relapse-free survival (P = 0.0016) and 5-year overall survival (P = 0.0024), and the tumor size separated by 7 cm was also a prognostic factor. There was significant difference in CDO1 gene methylation according to the tumor size (P = 0.036). BEA patients with CDO1 gene methylation were shown marginally significantly poorer prognosis (P = 0.054) than otherwise patients. In conclusion, higher CDO1 gene methylation was seen in BEA at earlier stage than in squamous cell carcinoma, and it may account for aggressive phenotype of BEA.

Background: Neoadjuvant chemoradiotherapy (NCRT) for advanced rectal cancer (RC) is a well-evidenced therapy; however, some RC patients have no therapeutic response. Patient selection for NCRT so that non-responsive patients are excluded has been subjective. To date, no molecular markers indicating radiation sensitivity have been reported. Methods: We irradiated six colorectal cancer (CRC) cell lines and identified HCT116 cells as radiation-sensitive and HCT15 and DLD-1 cells as radiation resistant. Using a microarray, we selected candidate radiation sensitivity marker genes by choosing genes whose expression was consistent with a radiation-resistant or sensitive cell phenotype. Results: Among candidate genes, cellular retinol binding protein 1 (CRBP1) was of particular interest because it was not only induced in HCT116 cells by tentative 10 Gy radiation treatments, but also its expression was increased in HCT116-derived radiation-resistant cells vs parental cells. Forced expression of CRBP1 decreased the viability of both HCT15 and DLD-1 cells in response to radiation therapy. We also confirmed that CRBP1 was epigenetically silenced by hypermethylation of its promoter DNA, and that the quantitative methylation value of CRBP1 significantly correlated with histological response in RC patients with NCRT (P=0.031). Conclusions: Our study identified CRBP1 as a radiation-sensitive predictor in RC.

Although small bowel cancer (SBC) is extremely rare, its prognosis is poor, and molecular mechanism of the SBC development remains unclear. The aim of our study is to elucidate whether DNA methylation of the promoter region of the cancer-specific methylation gene, cysteine dioxygenase 1 (CDO1), contributes to the carcinogenic process in SBC. The study group comprised patients with 53 patients with SBC, 107 colorectal cancer (CRC), and other rare tumors of the small intestine such as 4 malignant lymphomas, 2 leiomyosarcomas, and 9 gastrointestinal stromal tumors. We analyzed the extent of methylation in each tissue using quantitative TaqMan methylation-specific PCR for CDO1. Significantly higher CDO1 methylation was observed in cancer tissues compared with non-cancerous mucosa of the small intestine (ROC = 0.96). Among the various clinicopathological factors, positive correlation of CDO1 methylation with tumor diameter was observed (R = 0.31, p = 0.03), and the CDO1 methylation level was a possible prognostic factor for relapse-free survival (p = 0.09). Compared with CRC, SBC had a significantly poorer prognosis (p = 0.007) and displayed a significantly higher CDO1 methylation level (p < 0.0001). Intriguingly, especially in pStage I/II, there were robust prognostic difference between SBC and CRC (p = 0.08 / p < 0.0001), which may reflect CDO1 methylation status (p = 0.02 / p = 0.001). Among small bowel tumors, CDO1 methylation in SBC was higher in order of malignant lymphoma, cancer, and leiomyosarcoma/GIST (p = 0.002) by ANOVA. The CDO1 gene shows extremely cancer-specific hypermethylation, and it can be a prognostic marker in SBC.

We have demonstrated that CDO1 methylation is frequently found in various cancers, including esophageal squamous cell carcinoma (ESCC), but its clinical relevance has remained elusive. CDO1 methylation was investigated in 169 ESCC patients who underwent esophagectomy between 1996 and 2007. CDO1 methylation was assessed by Q-MSP (quantitative methylation specific PCR), and its clinical significance, including its relationship to prognosis, was analyzed. (i) The median TaqMeth value of CDO1 methylation was 9.4, ranging from 0 to 279.5. CDO1 methylation was significantly different between cStage I and cStage II/III (P = 0.02). (ii) On the log-rank plot, the optimal cut-off value was determined to be 8.9; ESCC patients with high CDO1 methylation showed a significantly worse prognosis than those with low CDO1 methylation (P = 0.02). (iii) A multivariate Cox proportional hazards model identified only CDO1 hypermethylation as an independent prognostic factor (HR 2.00, CI 1.09-3.78, P = 0.03). (iv) CDO1 hypermethylation stratified ESCC patients' prognosis in cStage II/III for both neoadjuvant chemo(radio)therapy (NAC)-positive and NAC-negative cases. Moreover, the CDO1 methylation level was significantly lower in cases with Grade 2/3 than in those with Grade 0/1 (P = 0.02) among cStage II/III ESCC patients with NAC. Promoter DNA hypermethylation of CDO1 could be an independent prognostic factor in ESCC; it may also reflect NAC eradication of tumor cells in the primary tumors.

We have demonstrated that CDO1 methylation is frequently found in various cancers, including esophageal squamous cell carcinoma (ESCC), but its clinical relevance has remained elusive. CDO1 methylation was investigated in 169 ESCC patients who underwent esophagectomy between 1996 and 2007. CDO1 methylation was assessed by Q-MSP (quantitative methylation specific PCR), and its clinical significance, including its relationship to prognosis, was analyzed. (i) The median TaqMeth value of CDO1 methylation was 9.4, ranging from 0 to 279.5. CDO1 methylation was significantly different between cStage I and cStage II/III (P = 0.02). (ii) On the log-rank plot, the optimal cut-off value was determined to be 8.9; ESCC patients with high CDO1 methylation showed a significantly worse prognosis than those with low CDO1 methylation (P = 0.02). (iii) A multivariate Cox proportional hazards model identified only CDO1 hypermethylation as an independent prognostic factor (HR 2.00, CI 1.09-3.78, P = 0.03). (iv) CDO1 hypermethylation stratified ESCC patients' prognosis in cStage II/III for both neoadjuvant chemo(radio)therapy (NAC)-positive and NAC-negative cases. Moreover, the CDO1 methylation level was significantly lower in cases with Grade 2/3 than in those with Grade 0/1 (P = 0.02) among cStage II/III ESCC patients with NAC. Promoter DNA hypermethylation of CDO1 could be an independent prognostic factor in ESCC; it may also reflect NAC eradication of tumor cells in the primary tumors.

症例は49歳，男性．1カ月前から心窩部痛，半月前から尿の黄染に気づき来院した．腹部CT検査で膵頭部に不均一な造影効果を持つ腫瘤を認め，腫瘤の頭側に嚢胞性病変を認めた．MRCP検査では，総胆管と主膵管が嚢胞と腫瘍により圧排され拡張していた．血管造影検査では明らかな血管侵襲を認めず，膵頭部の腫瘤は不均一な造影効果を認めた．膵頭部癌と術前診断し，膵頭十二指腸切除術を施行した．術後，病理組織検査で4.3cm×4.2cm大の高分化型非機能性膵内分泌癌と診断された．主膵管は腫瘍によって破壊され，腫瘍の頭側に貯留嚢胞を認めた．総胆管は腫瘍により圧排され十二指腸乳頭近くで閉塞していた．術後経過は良好で退院した．

Background Progression of colorectal cancer (CRC) has been explained by genomic abnormalities along with the adenoma-carcinoma sequence theory (ACS). The aim of our study is to elucidate whether the promoter DNA methylation of the cancer-specific methylation gene, cysteine dioxygenase 1 (CDO1), contributes to the carcinogenic process in CRC. Methods The study group comprised 107 patients with CRC who underwent surgical resection and 90 adenomas treated with endoscopic resection in the Kitasato University Hospital in 2000. We analyzed the extent of methylation in each tissue using quantitative TaqMan methylation-specific PCR for CDO1. Results The methylation level increased along with the ACS process (p < 0.0001), and statistically significant differences were found between normal-appearing mucosa (NAM) and low-grade adenoma (p < 0.0001), and between low-grade adenoma and high-grade adenoma (p = 0.01), but not between high-grade adenoma and cancer with no liver metastasis. Furthermore, primary CRC cancers with liver metastasis harbored significantly higher methylation of CDO1 than those without liver metastasis (p = 0.02). As a result, the area under the curve by CDO1 promoter methylation was 0.96, 0.80, and 0.67 to discriminate cancer from NAM, low-grade adenoma from NAM, and low-grade adenoma from high-grade adenoma, respectively. Conclusions CDO1 methylation accumulates during the ACS process, and consistently contributes to CRC progression.

Epigenetic alterations by promoter DNA hypermethylation and gene silencing in cancer have been reported over the past few decades. DNA hypermethylation has great potential to serve as a screening marker, a prognostic marker, and a therapeutic surveillance marker in cancer clinics. Some bodily fluids, such as stool or urine, were obtainable without any invasion to the body. Thus, such bodily fluids were suitable samples for high throughput cancer surveillance. Analyzing the methylation status of bodily fluids around the cancer tissue may, additionally, lead to the early detection of cancer, because several genes in cancer tissues are reported to be cancer-specifically hypermethylated. Recently, several studies that analyzed the methylation status of DNA in bodily fluids were conducted, and some of the results have potential for future development and further clinical use. In fact, a stool DNA test was approved by the U.S. Food and Drug Administration (FDA) for the screening of colorectal cancer. Another promising methylation marker has been identified in various bodily fluids for several cancers. We reviewed studies that analyzed DNA methylation in bodily fluids as a less-invasive cancer screening.