Germline BRCA2 variant with low variant allele frequency detected in tumor-only comprehensive genomic profiling.

Germline BRCA1/2 variants in comprehensive genomic profiling (CGP) often exhibit variant allele frequency (VAF) exceeding 50%. However, when genomic loss occurs at the ipsilateral allele, including the germline variant in tumor cells, the VAF is low. This case report presents a patient with uterine sarcoma with a pathogenic BRCA2 mutation and low VAF in tumor-only CGP, which was later identified as a germline variant. When genomic alterations in BRCA1/2 are identified in tumor-only CGP, the possible germline origin of the variants should be considered, even if their VAF is very low.

BRCA1/2 reversion mutations in a pan-cancer cohort.

Tumor sensitivity to platinum (Pt)-based chemotherapy and poly(adenosine diphosphate ribose) polymerase (PARP) inhibitors is increased by homologous recombination deficiency-causing mutations; in particular, reversion mutations cause drug resistance by restoring protein function. Treatment response is predicted by breast cancer susceptibility gene 1/2 (BRCA1/2) mutations; however, BRCA1/2 reversion mutations have not been comprehensively studied in pan-cancer cohorts. We aimed to characterize BRCA1/2 reversion mutations in a large pan-cancer cohort of Japanese patients by retrospectively analyzing sequencing data for BRCA1/2 pathogenic/likely pathogenic mutations in 3738 patients with 32 cancer types. We identified somatic mutations in tumors or circulating cell-free DNA that could restore the ORF of adverse alleles, including reversion mutations. We identified 12 (0.32%) patients with somatic BRCA1 (n = 3) and BRCA2 (n = 9) reversion mutations in breast (n = 4), ovarian/fallopian tube/peritoneal (n = 4), pancreatic (n = 2), prostate (n = 1), and gallbladder (n = 1) cancers. We identified 21 reversion events-BRCA1 (n = 3), BRCA2 (n = 18)-including eight pure deletions, one single-nucleotide variant, six multinucleotide variants, and six deletion-insertions. Seven (33.3%) reversion deletions showed a microhomology length greater than 1 bp, suggesting microhomology-mediated end-join repair. Disease course data were obtained for all patients with reversion events: four patients acquired mutations after PARP-inhibitor treatment failure, two showed somatic reversion mutations after disease progression, following Pt-based treatment, five showed mutations after both treatments, one patient with pancreatic cancer and BRCA1 reversion mutations had no history of either treatment. Although reversion mutations commonly occur in BRCA-associated cancers, our findings suggest that reversion mutations due to Pt-chemotherapy might be correlated with BRCA1/2-mediated tumorigenesis even in non-BRCA-associated histologies.

Patient survey on cancer genomic medicine in Japan under the national health insurance system.

In Japan, comprehensive genomic profiling (CGP) tests have been reimbursed under the national health care system for solid cancer patients who have finished standard treatment. More than 50,000 patients have taken the test since June 2019. We performed a nation-wide questionnaire survey between March 2021 and July 2022. Questionnaires were sent to 80 designated Cancer Genomic Medicine Hospitals. Of the 933 responses received, 370 (39.7%) were web based and 563 (60.3%) were paper based. Most patients (784, 84%) first learned about CGP tests from healthcare professionals, and 775 (83.1%) gave informed consent to their treating physician. At the time of informed consent, they were most worried about test results not leading to novel treatment (536, 57.4%). On a scale of 0-10, 702 respondents (75.2%) felt that the explanations of the test result were easy to understand (7 or higher). Ninety-one patients (9.8%) started their recommended treatment. Many patients could not receive recommended treatment because no approved drugs or clinical trials were available (102/177, 57.6%). Ninety-eight patients (10.5%) did not wish their findings to be disclosed. Overall satisfaction with the CGP test process was high, with 602 respondents (64.5%) giving a score of 7-10. The major reason for choosing 0-6 was that the CGP test result did not lead to new treatment (217/277, 78.3%). In conclusion, satisfaction with the CGP test process was high. Patients and family members need better access to information. More patients need to be treated with genomically matched therapy.

Clinical predominance of whole-exome sequencing to evaluate microsatellite instability status.

The microsatellite instability (MSI)/mismatch repair (MMR) status is one of the critical genomic biomarkers for predicting patient response to immune checkpoint inhibitors (ICIs). In this study, we aimed to investigate the concordance among the MSIsensor score obtained from whole-exome sequencing (WES), which could be a futuristic clinical cancer sequencing method, using only tumor tissues, MSI-PCR results, and immunohistochemistry (IHC) results to analyze various solid cancer types. We first endeavored to set the cut-off value of MSIsensor to determine functional deficient mismatch repair (f-dMMR) status. The MSI status of 1054 patients analyzed using WES was evaluated using MSIsensor. In addition, 87 of these patients were further analyzed using MSI-PCR and MMR IHC to calculate the sensitivity and specificity of the MSIsensor cut-off score. Our results showed that score 12.5 was an adequate cut-off score equivalent to PCR-confirmed MSS/MSI-low and MSI-high statuses, with sensitivity, specificity, and area under the curve values of 95.2%, 100%, and 0.998, respectively. Moreover, we identified false-positive cases of tumors with high mutational burden with an MSIsensor score <12.5, and optional IHC examination could rescue these cases. In conclusion, the MSIsensor score obtained using WES with tumor tissue showed a high clinical validity, with a cut-off value of 12.5 for f-dMMR detection, in combination with optional IHC analysis for MMR. Our novel algorithm will provide insights into the development of ICIs for cancer treatment, particularly when WES becomes a more common cancer genomic test in the near future.

Human resources for administrative work to carry out a comprehensive genomic profiling test in Japan.

Comprehensive genomic profiling (CGP) tests have been nationally reimbursed in Japan since June 2019 under strict restrictions, and over 46,000 patients have taken the test. Core Hospitals and Designated Hospitals host molecular tumor boards, which is more time-consuming than simply participating in them. We sent a questionnaire to government-designated Cancer Genomic Medicine Hospitals, including all 12 Core Hospitals, all 33 Designated Hospitals, and 117 of 188 Cooperative Hospitals. The questionnaire asked how much time physicians and nonphysicians spent on administrative work for cancer genomic medicine. For every CGP test, 7.6 h of administrative work was needed. Physicians spent 2.7 h/patient, while nonphysicians spent 4.9 h/patient. Time spent preparing for molecular tumor boards, called Expert Panels, was the longest, followed by time spent participating in Expert Panels. Assuming an hourly wage of ¥24,000/h for physicians and ¥2800/h for nonphysicians, mean labor cost was ¥78,071/patient. On a monthly basis, more time was spent on administrative work at Core Hospitals compared with Designated Hospitals and Cooperative Hospitals (385 vs. 166 vs. 51 h/month, respectively, p < 0.001). Consequently, labor cost per month was higher at Core Hospitals than at Designated Hospitals and Cooperative Hospitals (¥3,951,854 vs. ¥1,687,167 vs. ¥487,279/month, respectively, p < 0.001). Completing a CGP test for a cancer patient in Japan is associated with significant labor at each hospital, especially at Core Hospitals. Streamlining the exchange of information and simplifying Expert Panels will likely alleviate this burden.

Neutron crystallography of copper amine oxidase reveals keto/enolate interconversion of the quinone cofactor and unusual proton sharing.

Recent advances in neutron crystallographic studies have provided structural bases for quantum behaviors of protons observed in enzymatic reactions. Thus, we resolved the neutron crystal structure of a bacterial copper (Cu) amine oxidase (CAO), which contains a prosthetic Cu ion and a protein-derived redox cofactor, topa quinone (TPQ). We solved hitherto unknown structures of the active site, including a keto/enolate equilibrium of the cofactor with a nonplanar quinone ring, unusual proton sharing between the cofactor and the catalytic base, and metal-induced deprotonation of a histidine residue that coordinates to the Cu. Our findings show a refined active-site structure that gives detailed information on the protonation state of dissociable groups, such as the quinone cofactor, which are critical for catalytic reactions.

Comparing the Efficacy and Safety of Gemcitabine plus Nab-Paclitaxel versus Gemcitabine Alone in Older Adults with Unresectable Pancreatic Cancer.

BACKGROUND: Gemcitabine plus nab-paclitaxel (GnP) has been a standard treatment for unresectable pancreatic cancer (uPC); however, the current treatment status and usefulness in older adults with uPC remain unclear. Therefore, we aimed to investigate the patient background and compare the efficacy and safety of GnP versus other treatments in older adults with uPC. PATIENTS AND METHODS: In this prospective observational study, we enrolled 233 eligible patients aged ≥76 years with pathologically proven, clinically uPC, and no history of chemotherapy from 55 Japanese centers during September 2018-September 2019. The main endpoints were overall survival (OS), progression-free survival (PFS), and safety. Geriatric assessments were performed upon registration and after 3 months. To adjust for confounders, we conducted propensity score-matched analyses. RESULTS: GnP, gemcitabine alone (Gem), best supportive care, and other therapies were administered to 116, 72, 16, and 29 patients, respectively. In the propensity score-matched analysis, 42 patients each were selected from the GnP and Gem groups. The median OS was longer in the GnP group than in the Gem group (12.2 vs. 9.4 months; hazard ratio [HR], 0.65; 95% CI, 0.37-1.13). The median PFS was significantly longer in the GnP group than in the Gem group (9.2 vs. 3.7 months; HR, 0.38; 95% CI, 0.23-0.64). The incidence of severe adverse events was higher with GnP than with Gem; however, the difference was not significant. CONCLUSION: GnP is more efficacious than Gem in patients aged ≥76 years with uPC despite demonstrating a higher incidence of severe adverse events.

Possible implication of intermolecular epitope spreading in the production of anti-glomerular basement membrane antibody in anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVES: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is sometimes complicated by anti-glomerular basement membrane (GBM) disease. Proteases, including elastase, released from neutrophils activated by ANCA are implicated in the pathogenesis of AAV. Epitopes of anti-GBM antibody exist in the α3-subunit non-collagenous (NC1) domain of collagen type IV [Col (IV)]. This region, called α3(IV)NC1, is structurally cryptic. This study aimed to determine the production mechanism of anti-GBM antibody in AAV. METHODS: We first examined whether α3(IV)NC1 could be revealed by the digestion of formalin-fixed, paraffin-embedded (FFPE) normal kidney sections and Col (IV) by proteases, including neutrophil elastase, using immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA). Next, the reveal of α3(IV)NC1 and the infiltration of CD11c+ macrophages in the affected kidneys were evaluated by IHC and immunofluorescent staining using FFPE sections. Finally, the production of anti-GBM antibody in AAV rats was determined by ELISA. RESULTS: α3(IV)NC1 was revealed by the digestion of FFPE normal kidney sections and Col (IV) by proteases. Although the reveal of α3(IV)NC1 was observed in sclerotic glomeruli regardless of causative diseases, CD11c+ macrophages near α3(IV)NC1 were characteristics of AAV. Anti-GBM antibody was produced subsequent to ANCA in some AAV rats. IHC demonstrated the reveal of α3(IV)NC1 in affected renal tissues and the infiltration of CD11c+ macrophages around the sites. CONCLUSIONS: The collective findings suggest that, in AAV, proteases released from neutrophils activated by ANCA digest Col (IV) and result in the reveal of α3(IV)NC1, CD11c+ macrophages present GBM epitopes, and then the host's immune system produce anti-GBM antibody.

The diagnosis of early pneumoconiosis in dust-exposed workers: comparison of chest radiography and computed tomography.

BACKGROUND: Chest radiography (CR) is employed as the evaluation of pneumoconiosis; however, we sometimes encounter cases in which computed tomography (CT) is more effective in detecting subtle pathological changes or cases in which CR yields false-positive results. PURPOSE: To compare CR to CT in the diagnosis of early-stage pneumoconiosis. MATERIAL AND METHODS: CR and CT were performed for 132 workers with an occupational history of mining. We excluded 23 cases of arc-welder's lung. Five readers who were experienced chest radiologists or pulmonologists independently graded the pulmonary small opacities on CR of the remaining 109 cases. We then excluded 37 cases in which the CT data were not sufficient for grading. CT images of the remaining 72 cases were graded by the five readers. We also assessed the degree of pulmonary emphysema in those cases. RESULTS: The grade of profusion on CR (CR score) of all five readers was identical in only 5 of 109 cases (4.6%). The CR score coincided with that on CT in 40 of 72 cases (56%). The CT score was higher than that on CR in 13 cases (18%). On the other hand, the CT score was lower than that on CR in 19 cases (26%). The incidence of pulmonary emphysema was significantly higher in patients whose CR score was higher than their CT score. CONCLUSION: CT is more sensitive than CR in the evaluation of early-stage pneumoconiosis. In cases with emphysema, the CR score tends to be higher in comparison to that on CT.

In crystallo thermodynamic analysis of conformational change of the topaquinone cofactor in bacterial copper amine oxidase.

In the catalytic reaction of copper amine oxidase, the protein-derived redox cofactor topaquinone (TPQ) is reduced by an amine substrate to an aminoresorcinol form (TPQamr), which is in equilibrium with a semiquinone radical (TPQsq). The transition from TPQamr to TPQsq is an endothermic process, accompanied by a significant conformational change of the cofactor. We employed the humid air and glue-coating (HAG) method to capture the equilibrium mixture of TPQamr and TPQsq in noncryocooled crystals of the enzyme from Arthrobacter globiformis and found that the equilibrium shifts more toward TPQsq in crystals than in solution. Thermodynamic analyses of the temperature-dependent equilibrium also revealed that the transition to TPQsq is entropy-driven both in crystals and in solution, giving the thermodynamic parameters that led to experimental determination of the crystal packing effect. Furthermore, we demonstrate that the binding of product aldehyde to the hydrophobic pocket in the active site produces various equilibrium states among two forms of the product Schiff-base, TPQamr, and TPQsq, in a pH-dependent manner. The temperature-controlled HAG method provides a technique for thermodynamic analysis of conformational changes occurring in protein crystals that are hardly scrutinized by conventional cryogenic X-ray crystallography.

Targeted amplicon sequencing for primary tumors and matched lymph node metastases in patients with extrahepatic cholangiocarcinoma.

BACKGROUND: Lymph node metastasis (LNM) is one of the most adverse prognostic factors in extrahepatic cholangiocarcinoma (EHCC) cases. As next-generation sequencing technology has become more widely available, the genomic profile of biliary tract carcinoma has been clarified. However, whether LNMs have additional genomic alterations in patients with EHCC has not been investigated. Here, we aimed to compare the genomic alterations between primary tumors and matched LNMs in patients with EHCC. METHODS: Sixteen patients with node-positive EHCCs were included. Genomic DNA was extracted from tissue samples of primary tumors and matched LNMs. Targeted amplicon sequencing of 160 cancer-related genes was performed. RESULTS: Among the 32 tumor samples from 16 patients, 91 genomic mutations were identified. Genomic mutations were noted in 31 genes, including TP53, MAP3K1, SMAD4, APC, and ARID1A. TP53 mutations were most frequently observed (12/32; 37.5%). Genomic mutation profiles were highly concordant between primary tumors and matched LNMs (13/16; 81.3%), and an additional genomic mutation of CDK12 was observed in only one patient. CONCLUSION: Genomic mutations were highly concordant between primary tumors and matched LNMs, suggesting that genotyping of archived primary tumor samples may help predict genomic mutations of metastatic tumors in patients with EHCC.

A Phase I Trial of Oxaliplatin, Irinotecan, and S-1 Combination Therapy (OX-IRIS) as Chemotherapy for Unresectable Pancreatic Cancer (HGCSG 1403).

LESSONS LEARNED: Because S-1 is orally administered, OX-IRIS does not necessitate the continuous infusion of 5-FU and is more convenient. The recommended dose of OX-IRIS was determined to be level -1 (oxaliplatin, 65 mg/m2 ; irinotecan, 100 mg/m2 ; S-1, 80 mg/m2 ), which has manageable safety and promising anticancer activities. BACKGROUND: OX-IRIS is a new combination therapy of oxaliplatin, irinotecan, and S-1 for unresectable pancreatic ductal adenocarcinoma (PDAC), which may be beneficial because S-1 is administered orally and continuous infusion of 5-fluorouracil (5-FU) is not needed. METHODS: Patients who had not received prior therapy for unresectable PDAC were enrolled. Adenocarcinoma or adenosquamous histology was required. Oxaliplatin and irinotecan were administered on days 1 and 15; S-1 was administered orally twice a day on days 1-14, followed by 14 days of rest (one cycle). Primary endpoints were dose-limiting toxicity (DLT) and maximum tolerated dose (MTD). Secondary endpoints were safety, overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). RESULTS: In level 0 (oxaliplatin, 85 mg/m2 ; irinotecan, 100 mg/m2 ; S-1, 80 mg/m2 ), two of five patients experienced DLT. In level -1 (oxaliplatin, 65 mg/m2 ; irinotecan, 100 mg/m2 ; S-1, 80 mg/m2 ), DLT could not be evaluated in two of eight patients because one cycle was not completed; one of the remaining six patients experienced DLT. Anemia, thrombocytopenia, fatigue, nausea, anorexia, diarrhea, and peripheral sensory neuropathy were seen frequently in levels 0 and -1. ORR was 30% in levels 0 and -1. Median progression-free survival and median overall survival were 4.1 months (95% confidence interval [CI], 0.0-8.9 months) and 13.7 months (95% CI, 4.8-22.6 months), respectively. CONCLUSION: MTD of OX-IRIS therapy was estimated to be level 0, and the recommended dose (RD) for future trial was level -1.

Analysis of risk factors for immune-related adverse events in various solid tumors using real-world data.

The aim of this study was to determine the risk factors for immune-related adverse events (irAEs) induced by immune checkpoint inhibitors. The authors conducted a retrospective study in which patients with malignant melanoma, non-small-cell lung cancer, gastric cancer or renal cell carcinoma who received anti-PD-1/PD-L1 antibodies were included. Of 247 patients, 118 developed a total of 182 irAEs. In the multivariate Fine-Gray regression analysis, serum albumin level ≥3.6 g/dl (hazard ratio: 1.62; 95% CI: 1.10-2.39; p = 0.015) and history of Type I hypersensitivity reactions (hazard ratio: 1.48; 95% CI: 1.02-2.14; p = 0.037) were significantly associated with the development of irAEs. High serum albumin levels and history of Type I hypersensitivity reactions are risk factors for irAEs.

Clinical impact of a cancer genomic profiling test using an in-house comprehensive targeted sequencing system.

Precision medicine is a promising strategy for cancer treatment. In this study, we developed an in-house clinical sequencing system to perform a comprehensive cancer genomic profiling test as a clinical examination and analyzed the utility of this system. Genomic DNA was extracted from tumor tissues and peripheral blood cells collected from 161 patients with different stages and types of cancer. A comprehensive targeted amplicon exome sequencing for 160 cancer-related genes was performed using next-generation sequencing (NGS). The sequencing data were analyzed using an original bioinformatics pipeline, and multiple cancer-specific gene alterations were identified. The success rate of our test was 99% (160/161), while re-biopsy was required for 24% (39/161) of the cases. Potentially actionable and actionable gene alterations were detected in 91% (145/160) and 46% (73/160) of the patients, respectively. The actionable gene alterations were frequently detected in PIK3CA (9%), ERBB2 (8%), and EGFR (4%). High tumor mutation burden (TMB) (≥10 mut/Mb) was observed in 12% (19/160) of the patients. The secondary findings in germline variants considered to be associated with hereditary tumors were detected in 9% (15/160) of the patients. Seventeen patients (11%, 17/160) were treated with genotype-matched therapeutic agents, and the response rate was 47% (8/17). The median turnaround time for physicians was 20 days, and the median survival time after the initial visit was 8.7 months. The results of the present study prove the feasibility of implementing in-house clinical sequencing as a promising laboratory examination technique for precision cancer medicine.

FOLFIRINOX as second-line chemotherapy for advanced pancreatic cancer: A subset analysis of data from a nationwide multicenter observational study in Japan.

BACKGROUND: Data on FOLFIRINOX as a second-line chemotherapy for advanced pancreatic cancer are limited. In the JASPAC06 study-a nationwide, multicenter, observational study-FOLFIRINOX for patients with unresectable or recurrent pancreatic cancer as any line of treatment showed favorable efficacy and safety in Japanese clinical practice. METHODS: We performed exploratory analyses of patients with unresectable or recurrent pancreatic cancer who received FOLFIRINOX as the second-line chemotherapy in Japanese clinical settings. RESULTS: Of the 399 evaluable patients, 44 were eligible for inclusion in the analysis. The patients' characteristics were as follows: median age, 62 years; men, 26 (59%); Eastern Cooperative Oncology Group-Performance status 0/1, 30 (68%)/14 (32%); disease status, recurrent/local/metastatic: 4 (9%)/8 (18%)/32 (73%). The initial dose was reduced in 28 (64%) patients. The median time to treatment failure and number of cycles were 4.5 (range, 0.2-19.1) months and 6 cycles (range, 1-13 or more), respectively. The major grade 3/4 adverse events were neutropenia in 29 (66%), leucopenia in 17 (39%), anorexia in 7 (16%), febrile neutropenia in 5 (11%), and anemia in 5 (11%) patients. The median overall survival, progression-free survival, and 1-year survival rates were 10.3 (95% confidence interval [CI], 7.2-13.3), 4.1 (95% CI, 2.6-5.5) months, and 30%, respectively. CONCLUSION: Our findings suggest that FOLFIRINOX as a second-line chemotherapy for advanced pancreatic cancer was effective in patients with a good performance status. It displayed toxicity similar to that observed with its use as a first-line treatment.

Exacerbation of mitral regurgitation after tricuspid valve replacement for isolated tricuspid regurgitation.

A 74-year-old woman, with a history of aortic valve replacement and open mitral commissurotomy due to rheumatic aortic and mitral stenosis, presented with dyspnea. She developed severe tricuspid regurgitation (TR), requiring tricuspid valve replacement (TVR). Despite an uneventful postoperative course, she was readmitted for dyspnea 2 months later. Trans-thoracic echocardiogram revealed severe mitral regurgitation (MR), despite mild MR at the time of TVR, which has not been previously reported. The main MR mechanism was increased left ventricular preload due to improved TR. Increased diuresis has controlled her congestive heart failure, but her MR remained moderate.

A novel in vivo assessment of fluid dynamics on aortic valve leaflet using epi-aortic echocardiogram.

BACKGROUND: Mechanical stress caused by blood flow, such as wall shear stress (WSS) and its related parameters, is key moderator of endothelial degeneration. However, an in vivo method to measure WSS on heart valves has not been developed. METHODS: We developed a novel approach, based on vector flow mapping using intraoperative epi-aortic echocardiogram, to measure WSS and oscillatory shear index (OSI) on the aortic valve. We prospectively enrolled 15 patients with normal valves, who underwent coronary artery bypass graft. RESULTS: Systolic WSS on the ventricularis (2.40 ± 0.44 Pa [1.45-3.00 Pa]) was higher than systolic WSS on the fibrosa (0.33 ± 0.08 Pa [0.14-0.47 Pa], P < .001) and diastolic WSS on the ventricularis (0.18 ± 0.07 Pa [0.04-0.28 Pa], P < .001). Oscillatory shear index on the fibrosa was higher than on the ventricularis (0.29 ± 0.04 [0.24-0.36] vs 0.05 ± 0.03 [0.01-0.12], P < .001). A pilot study involving two patients with severe aortic regurgitation showed significantly different values in fluid dynamics. CONCLUSION: Vector flow mapping method using intraoperative epi-aortic echocardiogram is an effective way of measuring WSS and OSI on normal aortic leaflet in vivo, allowing for better understanding of the pathophysiology of aortic valve diseases.

Impact of UGT1A1 genetic polymorphism on toxicity in unresectable pancreatic cancer patients undergoing FOLFIRINOX.

Studies have indicated an association between UDP-glucuronosyltransferase-1A1 (UGT1A1) genetic polymorphisms and irinotecan-induced toxicity. We undertook this study to investigate the association between UGT1A1 genetic polymorphisms and toxicity in patients treated with the FOLFIRINOX (comprising oxaliplatin, irinotecan, fluorouracil, and leucovorin) chemotherapy regimen in the JASPAC 06 study. Patients screened for UGT1A1*6 and UGT1A1*28, and treated with either the original FOLFIRINOX (oxaliplatin 85 mg/m2 , irinotecan 180 mg/m2 , leucovorin 200 mg/m2 , bolus 5-fluorouracil [5-FU] 400 mg/m2 , and continuous 5-FU 2400 mg/m2 ) or a modified FOLFIRINOX (oxaliplatin 85 mg/m2 , irinotecan 150 mg/m2 , leucovorin 200 mg/m2 , and continuous 5-FU 2400 mg/m2 ) as first-line chemotherapy were included. Of 199 patients eligible for this analysis, 79 patients were treated with the original FOLFIRINOX regimen and 120 patients were treated with the modified FOLFIRINOX regimen. In the original FOLFIRINOX group, 54 were UGT1A1 WT, and 25 were UGT1A1 heterozygous type (-/*6, 12 patients; -/*28, 13 patients). In the modified FOLFIRINOX group, 64 were UGT1A1 WT and 56 were UGT1A1 heterozygous type (-/*6, 33 patients; -/*28, 23 patients). In the original FOLFIRINOX group, the incidence of diarrhea was significantly higher among patients with UGT1A1 heterozygous type than among those with UGT1A1 WT and the incidence of leukopenia and diarrhea was significantly higher among patients with UGT1A1 -/*6 than among those with UGT1A1 -/*28. Patients with UGT1A1 heterozygous type, especially those with UGT1A1 -/*6, tended to show a higher incidence rate of severe adverse events, but this was not statistically significant. However, for patients who received the modified FOLFIRINOX, there was no difference in the frequency of adverse events due to UGT1A1 status. In conclusion, patients with heterozygous UGT1A1 polymorphisms treated with the original FOLFIRINOX regimen experienced severe toxicity more frequently than patients with WT UGT1A1.

Identification of O-acetylhomoserine sulfhydrylase, a putative enzyme responsible for methionine biosynthesis in Clostridioides difficile: Gene cloning and biochemical characterizations.

O-acetylhomoserine sulfhydrylase (OAHS) is a pyridoxal 5'-phosphate-dependent enzyme involved in microbial methionine biosynthesis. In this study, we report gene cloning, protein purification, and some biochemical characteristics of OAHS from Clostridioides difficile. The enzyme is a tetramer with molecular weight of 185 kDa. It possesses a high activity in the reaction of L-homocysteine synthesis, comparable to reported activities of OAHSes from other sources. OAHS activity is inhibited by metabolic end product L-methionine. L-Propargylglycine was found to be a suicide inhibitor of the enzyme. Substrate analogue Nγ -acetyl-L-2,4-diaminobutyric acid is a competitive inhibitor of OAHS with Ki = 0.04 mM. Analysis of C. difficile genome allows to suggest that the bacterium uses the way of direct sulfhydrylation for the synthesis of L-methionine. The data obtained may provide the basis for further study of the role of OAHS in the pathogenic bacterium and the development of potential inhibitors.

Age- and Body Size-Adjusted Left Ventricular End-Diastolic Dimension in a Japanese Hospital-Based Population.

BACKGROUND: Using the normal values for the East Asian population, we evaluated age- and body size-adjusted left ventricular end-diastolic dimension (LVEDD) and its prognostic impact in a hospital-based population in Japan. Methods and Results: We retrospectively analyzed data obtained from 4,444 consecutive patients who had undergone both transthoracic echocardiography and electrocardiography at Kitano Hospital in 2013. Those who presented with a history of previous episodes of myocardial infarction and severe or moderate valvular disease or with low ejection fraction (<50%) were excluded from the analysis. We calculated LVEDD adjusted by age and body surface area. A total of 3,474 patients were categorized into 3 groups: 401 with large adjusted LVEDD, 2,829 with normal adjusted LVEDD, and 244 with small adjusted LVEDD. Mean patient age in the large, normal, and small adjusted LVEDD groups was 66.6±18.4, 65.6±15.7, and 62.1±15.5 years, respectively (P<0.001). After adjusting for confounding factors, the excess adjusted 3-year risk of primary outcome of large adjusted LVEDD relative to normal LVEDD was significant (HR, 1.40; 95% CI: 1.08-1.78). The risk for primary outcomes of small adjusted LVEDD relative to normal adjusted LVEDD was significantly lower (HR, 0.55; 95% CI: 0.34-0.85). CONCLUSIONS: Adjusted large LVEDD has a deleterious impact on long-term mortality, whereas small LVEDD carried a significantly lower risk.