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 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.

Unique protonation states of aspartate and topaquinone in the active site of copper amine oxidase.

The oxidative deamination of biogenic amines, crucial in the metabolism of a wealth of living organisms, is catalyzed by copper amine oxidases (CAOs). In this work, on the ground of accurate molecular modeling, we provide a clear insight into the unique protonation states of the key catalytic aspartate residue Asp298 and the prosthetic group of topaquinone (TPQ) in the CAO of Arthrobacter globiformis (AGAO). This provides both extensions and complementary information to the crystal structure determined by our recent neutron diffraction (ND) experiment. The hybrid quantum mechanics/molecular mechanics (QM/MM) simulations suggest that the ND structure closely resembles a state in which Asp298 is protonated and the TPQ takes an enolate form. The TPQ keto form can coexist in the fully protonated state. The energetic and structural analyses indicate that the active site structure of the AGAO crystal is not a single state but rather a mixture of the different protonation and conformational states identified in this work.

Cytomegalovirus colitis in a patient undergoing postoperative adjuvant chemotherapy for lung adenocarcinoma with uracil-tegafur.

When we examine a patient with symptoms of acute enteritis in the course of chemotherapy with oral fluoropyrimidines such as uracil-tegafur (often referred to as UFT), we usually suspect 5-fluorouracil-induced enterocolitis. In case of persistent clinical symptoms despite discontinuation of chemotherapy, cytomegalovirus colitis should be considered in the differential diagnosis of chemotherapy-induced enterocolitis. We herein report the case of a patient who underwent surgery for lung adenocarcinoma followed by postoperative adjuvant chemotherapy with uracil-tegafur and was diagnosed as having cytomegalovirus colitis during the therapy. In the course of chemotherapy, cytomegalovirus colitis occasionally occurs even though the patient does not experience severe myelosuppression; thus, it is necessary that we recognize its potential occurrence.

Japanese apricot improves symptoms of gastrointestinal dysmotility associated with gastroesophageal reflux disease.

AIM: To investigate the effects of Japanese apricot (JA) consumption on gastroesophageal reflux disease (GERD)-related symptoms. METHODS: Participants included individuals living in Minabe-cho, a well-known JA-growing region, who received specific medical check-ups by the local community health service in 2010. GERD-related symptoms were examined in 1303 Japanese individuals using a validated questionnaire, the Frequency Scale for Symptoms of GERD (FSSG), which consists of 7 questions associated with acid reflux symptoms and 5 questions asking about gastrointestinal dysmotility symptoms. Each question was answered using a 4-point scale, with higher scores indicating more severe GERD-related symptoms. Subjects were divided into two groups according to their intake of dried and pickled JA: daily intake (≥ 1 JA daily) (392 subjects) and none or occasional intake (< 1 JA daily) (911 subjects). FSSG scores were compared between subjects who consumed JA daily and those who did not. Next, subjects were stratified by age, gender and Helicobacter pylori (H. pylori) status for subanalyses. RESULTS: Those who ate JA daily were significantly older than those who did not (60.6 ± 10.5 years vs 56.0 ± 11.0 years, P < 0.001). Total FSSG scores were significantly lower in subjects with daily JA intake than in those with none or only occasional intake (2.13 ± 3.14 vs 2.70 ± 3.82, P = 0.005). In particular, subjects who consumed JA daily showed significantly improved FSSG dysmotility scores compared with subjects who did not (1.05 ± 1.58 vs 1.46 ± 2.11, P < 0.001). In contrast, the FSSG reflux score did not differ between subjects with and without daily intake of JA (1.08 ± 1.90 vs 1.24 ± 2.11, P = 0.177). Subanalysis indicated that improvement in dysmotility by JA intake was specifically observed in non-elderly (1.24 ± 1.68 vs 1.62 ± 2.22, P = 0.005) and H. pylori-negative subjects (0.99 ± 1.58 vs 1.57 ± 2.06, P < 0.001). GERD patients (total FSSG score ≥ 8) were less frequently observed among subjects with daily intake of JA as compared to those without daily intake of JA (6.1% vs 9.7%, P = 0.040). CONCLUSION: Daily JA intake may improve digestive dysmotility symptoms, resulting in relief of GERD symptoms. The effect is more obvious in non-elderly and H. pylori-negative subjects.

Reaction mechanism and molecular basis for selenium/sulfur discrimination of selenocysteine lyase.

Selenocysteine lyase (SCL) catalyzes the pyridoxal 5'-phosphate-dependent removal of selenium from l-selenocysteine to yield l-alanine. The enzyme is proposed to function in the recycling of the micronutrient selenium from degraded selenoproteins containing selenocysteine residue as an essential component. The enzyme exhibits strict substrate specificity toward l-selenocysteine and no activity to its cognate l-cysteine. However, it remains unclear how the enzyme distinguishes between selenocysteine and cysteine. Here, we present mechanistic studies of selenocysteine lyase from rat. ESI-MS analysis of wild-type and C375A mutant SCL revealed that the catalytic reaction proceeds via the formation of an enzyme-bound selenopersulfide intermediate on the catalytically essential Cys-375 residue. UV-visible spectrum analysis and the crystal structure of SCL complexed with l-cysteine demonstrated that the enzyme reversibly forms a nonproductive adduct with l-cysteine. Cys-375 on the flexible loop directed l-selenocysteine, but not l-cysteine, to the correct position and orientation in the active site to initiate the catalytic reaction. These findings provide, for the first time, the basis for understanding how trace amounts of a selenium-containing substrate is distinguished from excessive amounts of its cognate sulfur-containing compound in a biological system.