We clarified the clinical prevalence of ovarian metastases from colorectal cancers (CRCs) in 296 female patients with CRC and evaluated clinical outcomes with relation to their mutational profiles, such as BRAF/KRAS mutation and microsatellite instability (MSI) status. The female CRCs were categorised into three subsets: CRCs with ovarian metastases [6.4% (n = 19), 5-year overall survival (OS) = 24.7%], CRCs with extra-ovarian metastases only [32.4% (n = 96), 5-year OS = 34.5%] and CRCs without any recurrence or metastasis [61.2% (n = 181), 5-year OS = 91.3%]. All patients with ovarian metastases underwent oophorectomy; of these, 9 who received preoperative chemotherapy had measurable metastases to extra-ovarian sites and the ovaries. Although 5 of 9 (56%) achieved partial response or complete response at extra-ovarian sites, no patient archived objective response at ovarian sites. Regarding the mutation profiles, in CRCs with extra-ovarian metastases only, the median survival time (MST) after initial treatments to progression to stage IV or recurrence was 13 [95% confidence interval (CI): 7–16 months] in BRAF-mutant and 34 months (95% CI: 22–58 months) in BRAF wild-type (P = 0.0033). Although ovarian metastases demonstrated poor response to systemic chemotherapy in CRCs with ovarian metastases, the MST after initial treatments to progression to stage IV or recurrence was 22 (95% CI: 21–25 months) in BRAF-mutant and 38 months (95% CI: 24–42 months) in BRAF wild-type (P = 0.0398). The outcomes of patients with ovarian metastases could be improved by oophorectomy regardless of their mutation profiles.

Because of the different forms of circulating miRNAs in plasma, Argonaute2 (Ago2)‐miRNAs and extracellular vesicles (EV‐miRNAs), we examined the two forms of extracellular miRNAs in vitro and developed a unique methodology to detect circulating Ago2‐miRNAs in small volumes of plasma. We demonstrated that Ago2‐miR‐21 could be released into the extracellular fluid by active export from viable cancer cells and cytolysis in vitro. As miR‐21 and miR‐200c were abundantly expressed in both metastatic liver sites and primary lesions, we evaluated Ago2‐miR‐21 as a candidate biomarker of both active export and cytolysis while Ago2‐miR‐200c as a biomarker of cytolysis in plasma obtained from colorectal cancer (CRC) patients before treatment and in a series of plasma obtained from CRC patients with liver metastasis who received systemic chemotherapy. The measurement of Ago2‐miR‐21 allowed us to distinguish CRC patients from subjects without CRC. The trend in ΔCt values for Ago2‐miR‐21 and ‐200c during chemotherapy could predict tumor response to ongoing treatment. Thus, capturing circulating Ago2‐miRNAs from active export can screen patients with tumor burdens, while capturing them from passive release by cytolysis can monitor tumor dynamics during chemotherapy treatment.

<b><i>Objective:</i></b> Keratin 19 (K19) expression is a potential predictor of poor prognosis in patients with hepatocellular carcinoma (HCC). To clarify the feature of K19-proficient HCC, we traced epigenetic footprints in cultured cells and clinical materials. <b><i>Patients and Methods:</i></b> In vitro, <i>KRT19</i> promoter methylation was analyzed and 5-aza-2’-deoxycytidine with trichostatin A (TSA) treatment was performed. Among 564 surgically resected HCCs, the clinicopathological relevance of K19-proficent HCCs was performed in comparison with hepatocytic (HepPar-1 and arginase-1), epithelial-mesenchymal transition (E-cadherin and vimentin), biliary differentiation-associated (K7 and NOTCH-1) markers, and epigenetic markers (<i>KRT19</i> promoter/long interspersed nucleotide element-1 [<i>LINE-1</i>] methylation status). <b><i>Results:</i></b> <i>KRT19</i> promoter methylation was clearly associated with K19 deficiency and 5-aza-2’-deoxycytidine with TSA treatment-stimulated K19 re-expression, implicating DNA methylation as a potential epigenetic process for K19 expression. After excluding HCCs with recurrence, TNM stage as IIIB or greater, preoperative therapy, transplantation, and combined hepatocellular cholangiocarcinoma, we assessed 125 of 564 HCC cases. In this cohort, K19 expression was found in 29 HCCs (23.2%) and corresponded with poor survival following surgery (<i>p</i> = 0.025) and extrahepatic recurrence-free survival (<i>p</i> = 0.017). Compared with K19-deficient HCCs, lower <i>KRT19</i> promoter methylation level was observed in K19-proficient HCCs (<i>p</i> &#x3c; 0.0001). Conversely, HCC with genome-wide <i>LINE-1</i> hypermethylation was frequently observed in K19-proficient HCCs (<i>p</i> = 0.0079). Additionally, K19 proficiency was associated with K7 proficiency (<i>p</i> = 0.043), and reduced E-cadherin and HepPar-1 expression (<i>p</i> = 0.043 and <i>p</i> &#x3c; 0.0001, respectively). <b><i>Conclusions:</i></b> K19-proficient HCC exhibited poor prognosis owing to extrahepatic recurrence, with molecular signatures differing from those in conventional cancer stem cells, providing novel insights of the heterogeneity underlying tumor development.

BackgroundThe gene expressions of netrin-1 dependence receptors, DCC and UNC5C, are frequently downregulated in many cancers. We hypothesized that downregulation of DCC and UNC5C has an important growth regulatory function in gastric tumorigenesis.ResultsIn the present study, a series of genetic and epigenetic analyses for DCC and UNC5C were performed in a Japanese cohort of 98 sporadic gastric cancers and corresponding normal gastric mucosa specimens. Loss of heterozygosity (LOH) analyses and microsatellite instability (MSI) analysis was applied to determine chromosomal instability (CIN) and MSI phenotypes, respectively. More than 5 % methylation in the DCC and UNC5C promoters were found in 45 % (44/98) and 32 % (31/98) gastric cancers, respectively, and in 9 % (9/105) and 5 % (5/105) normal gastric mucosa, respectively. Overall, 70 % (58 of 83 informative cases) and 51 % (40 of 79 informative cases) of gastric cancers harbored either LOH or aberrant methylation in the DCC and UNC5C genes, respectively. In total, 77 % (51 of 66 informative cases) of gastric cancers showed cumulative defects in these two dependence receptors and were significantly associated with chromosomal instability. Both DCC and UNC5C were inactivated in 97 % of CIN-positive gastric cancers and in 55 % of CIN-negative gastric cancers.ConclusionsDefect in netrin receptors is a common feature in gastric cancers. DCC alterations are apparent in the early stages, and UNC5C alterations escalate with the progression of the disease, suggesting that the cumulative alterations of netrin-1 receptors was a late event in gastric cancer progression and emphasizing the importance of this growth regulatory pathway in gastric carcinogenesis.Electronic supplementary materialThe online version of this article (doi:10.1186/s13148-015-0096-y) contains supplementary material, which is available to authorized users.

Background/Aim: The C-reactive protein (CRP) to albumin ratio (CAR) is associated with outcomes in patients with sepsis. We aimed to evaluate the significance of preoperative CAR in therapeutic outcomes after gallbladder carcinoma (GBC) resection. Patients and Methods: Fifty-three patients who underwent surgical resection for GBC between January 2008 and September 2019 were enrolled. We retrospectively investigated the relation between preoperative CAR and overall and disease-free survival. Results: The optimal cutoff CAR was 0.07. Multivariate analysis showed that i) R1 or R2 resection (p=0.033), ii) advanced tumor stage (p=0.047), iii) CAR≥0.07 (p=0.011), and iv) postoperative complications (p=0.028) were significant independent predictors of overall survival; moreover, higher carbohydrate antigen levels (p=0.036) and R1 or R2 resection (p<0.001) were significant independent predictors of disease-free survival. Conclusion: Preoperative CAR may be a significant independent predictor of long-term outcomes after GBC resection.

Background Mutations in the POLE gene result in an ultra-hypermutated phenotype in colorectal cancer (CRC); however, the molecular characterisation of epigenetic alterations remains unclear. We examined the genetic and epigenetic profiles of POLE-mutant CRC to elucidate the clinicopathological features of the associated genetic and epigenetic alterations. Results Tumour tissues (1,013) obtained from a cohort of patients with CRC were analysed to determine associations between the proofreading domain mutations of POLE with various clinicopathological variables, microsatellite instability (MSI) status, BRAF and KRAS mutations, and the methylation status of key regions of MLH1, MGMT, and SFRP2 promoters by calculating the methylation scores (range 0–6). Only four cases (0.4%) exhibited pathogenic POLE hotspot mutations (two p.P286R [c.857C > G], one p.V411L [c.1231G > C], and p.S459F [c.1376C > T] each), which were mutually exclusive to BRAF and KRAS mutations and MSI. CRC patients were divided into four subgroups: patients with POLE mutations (POLE, 0.4%, n = 4), patients with both MSI and extensive methylation in MLH1 (MSI-M, 2.9%, n = 29), patients with MSI but no extensive methylation in MLH1 (MSI-U, 3.6%, n = 36), and patients without MSI (non-MSI, 93.2%, n = 944). The POLE group was younger at diagnosis (median 52 years, P < 0.0001), with frequent right-sided tumour localisation (frequency of tumours located in the right colon was 100%, 93.1%, 36.1%, and 29.9% in POLE, MSI-M, MSI-U, and non-MSI, respectively; P < 0.0001), and was diagnosed at an earlier stage (frequency of stages I–II was 100%, 72.4%, 77.8%, and 46.6% in POLE, MSI-M, MSI-U, and non-MSI, respectively, P < 0.0001). The mean methylation score in POLE was not different from that in MSI-U and non-MSI, but the methylation signature was distinct from that of the other subgroups. Additionally, although the examined number of POLE-mutant tumours was small, the number of CD8-positive cells increased in tumours with partial methylation in the MLH1 gene. Conclusions CRC patients with POLE proofreading mutations are rare. Such mutations are observed in younger individuals, and tumours are primarily located in the right colon. Diagnosis occurs at an earlier stage, and distinct epigenetic alterations may be associated with CD8 cell infiltration.

Backgound: This study aimed to determine the usefulness of the Controlling Nutritional Status (CONUT) scorescore for predicting postoperative pancreatic fistula (POPF). Patients and Methods: Data from 108 consecutive pancreaticoduodenectomy cases performed at the Surgery Department of Iwakuni Clinical Center, from April 2008 to May 2018, were included. Preoperative patient data and postoperative complication data were collected. Results: Of the 108 patients (male=65; female=43; mean age=70 years), 41 (37.9%) had indication for pancreaticoduodenectomy due to pancreatic carcinoma. Grade B or higher POPF was diagnosed in 32 patients (29.6%). In the multivariate analysis, body mass index ≥22 kg/m 2 [odds ratio (OR)=5.24; p=0.005], CONUT score ≥4 (OR=3.28; p=0.042), nonpancreatic carcinoma (OR=47.17; p=0.001), and a low computed tomographic contrast attenuation value (late/early ratio) (OR=4.39; p=0.029) were independent risk factors for POPF. Conclusion: Patients with high CONUT score are at high risk for POPF. Preoperative nutritional intervention such as immunonutrition might help reduce the POPF risk in these patients.

Postoperative pancreatic fistula (POPF) is the most important factor affecting morbidity and mortality after pancreaticoduodenectomy (PD). Patients with a high controlling nutritional status (CONUT) score, which is used to assess nutritional status, are expected to have high morbidity rates. This study aimed to determine the usefulness of the CONUT score. Methods: Data from 97 consecutive cases of PD performed in the Department of Surgery of Iwakuni Clinical Center, from April 2008 to May 2018, were included. Preoperative patient data, including sex, age, and hypertension, and postoperative complication data were collected to analyze pancreatic fistula occurrence. Results: Of the 97 patients, 2 9 patients (29.8%) were diagnosed with POPF ≥ B, with 26 cases (26.8%) classified as grade B and 3 (3.1%) as grade C. The mortality rate was 2.1% (2 of 97). In the univariate analysis, a significant association was observed between POPF and the following factors: body mass index (BMI) ≥ 22 kg/m 2 , high CONUT score, nonpancreatic carcinoma, and CT attenuation values. In multivariate analysis, BMI ≥ 22 kg/m 2 (odds ratio [OR], 6.16; P < 0.001), high CONUT score (OR, 3.77; P = 0.009), nonpancreatic carcinoma (OR, 5.72; P = 0.009), and CT attenuation values (late/early ratio) in the pancreas (OR, 9.07; P = 0.006) were independent risk factors for POPF. Conclusion: Patients with a high CONUT score are at high risk of POPF. Further study correlating preoperative nutritional intervention with risk of POPF is necessary.