Publications by authors named "Mayumi Kamada"

Background: In cancer genomic medicine, finding driver mutations involved in cancer development and tumor growth is crucial. Machine-learning methods to predict driver missense mutations have been developed because variants are frequently detected by genomic sequencing. However, even though the abnormalities in molecular networks are associated with cancer, many of these methods focus on individual variants and do not consider molecular networks.

View Article and Find Full Text PDF

The bone morphogenetic protein (BMP) pathway promotes differentiation and induces apoptosis in normal colorectal epithelial cells. However, its role in colorectal cancer (CRC) is controversial, where it can act as context-dependent tumor promoter or tumor suppressor. Here we have found that CRC cells reside in a BMP-rich environment based on curation of two publicly available RNA-sequencing databases.

View Article and Find Full Text PDF

Dynamic changes in cell properties lead to intratumor heterogeneity; however, the mechanisms of nongenetic cellular plasticity remain elusive. When the fate of each cell from colorectal cancer organoids was tracked through a clonogenic growth assay, the cells showed a wide range of growth ability even within the clonal organoids, consisting of distinct subpopulations; the cells generating large spheroids and the cells generating small spheroids. The cells from the small spheroids generated only small spheroids (S-pattern), while the cells from the large spheroids generated both small and large spheroids (D-pattern), both of which were tumorigenic.

View Article and Find Full Text PDF

Tumors demonstrating deficient mismatch repair (dMMR) account for 12%-15% of colorectal cancers (CRCs), but their characteristics have not been fully elucidated. The aim of this study was to characterize dMMR CRCs in terms of clinicopathological findings and molecular alterations. Immunostaining for mismatch repair (MMR) proteins was performed to determine MMR status, and then MLH1 promoter methylation and genetic variants of 25 genes involved in colorectal carcinogenesis were analyzed by next-generation sequencing in dMMR tumors.

View Article and Find Full Text PDF

Recent effective therapies enable most rheumatoid arthritis (RA) patients to achieve remission; however, some patients experience relapse. We aimed to predict relapse in RA patients through machine learning (ML) using data on ultrasound (US) examination and blood test. Overall, 210 patients with RA in remission at baseline were dichotomized into remission (n = 150) and relapse (n = 60) based on the disease activity at 2-year follow-up.

View Article and Find Full Text PDF

We report a 63-year-old woman came to our hospital with exertional dyspnea, palpitations, and abdominal distention. Echocardiography showed mitral, aortic, and tricuspid valve insufficiency, for which surgery was indicated. Twenty-six years ago, during dental therapy, she was diagnosed with metal allergy.

View Article and Find Full Text PDF
Article Synopsis
  • A 47-year-old woman with a history of mitral valve replacement was hospitalized due to shortness of breath and was found to have dysfunction in her bioprosthetic valve causing mitral stenosis.
  • Right heart catheterization indicated severe pulmonary hypertension and right ventricular dysfunction, leading to the decision to use percutaneous cardiopulmonary support during anesthesia induction.
  • The patient underwent a redo mitral valve replacement through a right mini-thoracotomy, which revealed severe calcification in the prosthetic valve's leaflets, and she was discharged home after 42 days post-surgery.
View Article and Find Full Text PDF

The biological processes of urothelial carcinogenesis are not fully understood, particularly regarding the relationship between specific genetic events, cell of origin, and molecular subtypes of subsequent tumors. N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN)-induced mouse bladder cancer is widely accepted as a useful model that recapitulates the pathway of human bladder tumorigenesis from dysplasia to invasive cancer via carcinoma in situ. However, the long and variable time of tumorigenesis often hinders efficient preclinical or translational research.

View Article and Find Full Text PDF

To promote the implementation of genomic medicine, we developed an integrated database, the Medical Genomics Japan Variant Database (MGeND). In its first release, MGeND provides data regarding genomic variations in Japanese individuals, collected by research groups in five disease fields. These variations consist of curated SNV/INDEL variants and susceptibility variants for diseases established by genome-wide association study analysis.

View Article and Find Full Text PDF
Article Synopsis
  • Tumor mutational burden (TMB), assessed using next-generation sequencing (NGS), may indicate how well solid tumors respond to immune checkpoint inhibitors, but the effects of preanalytical factors on TMB scores are not well understood.
  • A study of 199 patients found that low DNA library concentration, the use of formalin-fixed paraffin-embedded tissue samples, and longer storage times were linked to higher TMB scores, although only the sample type (FFPE) consistently impacted scores after adjusting for DNA concentration.
  • Results suggested that while a high TMB score can be promising for treatment responses, various factors like sample handling could skew results, pointing to the need for careful evaluation in clinical settings.
View Article and Find Full Text PDF

Next generation sequencing (NGS)-based tumor profiling identified an overwhelming number of uncharacterized somatic mutations, also known as variants of unknown significance (VUS). The therapeutic significance of mutations outside mutational hotspots, consisting of >50 types, in nonsmall cell lung carcinoma (NSCLC) is largely unknown. In fact, our pan-nation screening of NSCLC without hotspot mutations ( = 3,779) revealed that the majority (>90%) of cases with rare mutations, accounting for 5.

View Article and Find Full Text PDF

Background: Esophageal squamous cell carcinoma (ESCC) is one of the most intractable cancers, so the development of novel therapeutics has been required to improve patient outcomes. Curcumin, a polyphenol from Curcuma longa, exhibits various health benefits including antitumor effects, but its clinical utility is limited because of low bioavailability. Theracurmin (THC) is a highly bioavailable curcumin dispersed with colloidal submicron particles.

View Article and Find Full Text PDF
Article Synopsis
  • * In experiments using mouse mast cells, dexamethasone reduced the release of inflammatory substances and altered the expression of certain receptors compared to untreated cells.
  • * Topical dexamethasone not only decreased mast cell activity in the skin but also suggested that it could help manage inflammation without the need for IgE antibodies.
View Article and Find Full Text PDF

Recent innovations in next-generation sequencing (NGS) technologies have enabled comprehensive genomic profiling of human cancers in the clinical setting. The ability to profile has launched a worldwide trend known as precision medicine, and the fusion of genomic profiling and pharmacogenomics is paving the way for precision medicine for cancer. The profiling is coupled with information about chemical therapies available to patients with specific genotypes.

View Article and Find Full Text PDF

As one of the few irreversible protein posttranslational modifications, proteolytic cleavage is involved in nearly all aspects of cellular activities, ranging from gene regulation to cell life-cycle regulation. Among the various protease-specific types of proteolytic cleavage, cleavages by casapses/granzyme B are considered as essential in the initiation and execution of programmed cell death and inflammation processes. Although a number of substrates for both types of proteolytic cleavage have been experimentally identified, the complete repertoire of caspases and granzyme B substrates remains to be fully characterized.

View Article and Find Full Text PDF

Objectives: We aimed to examine the association between homologous recombination repair (HRR)-related gene mutations and efficacy of oxaliplatin-based chemotherapy in patients with pancreatic ductal adenocarcinoma (PDAC).

Results: Non-synonymous mutations in HRR-related genes were found in 13 patients and only one patient had a family history of pancreatic cancer. Eight patients with HRR-related gene mutations (group A) and nine without HRR-related gene mutations (group B) received oxaliplatin-based chemotherapy.

View Article and Find Full Text PDF

According to the increase of data generated from analytical instruments, application of artificial intelligence(AI)technology in medical field is indispensable. In particular, practical application of AI technology is strongly required in "genomic medicine" and "genomic drug discovery" that conduct medical practice and novel drug development based on individual genomic information. In our laboratory, we have been developing a database to integrate genome data and clinical information obtained by clinical genome analysis and a computational support system for clinical interpretation of variants using AI.

View Article and Find Full Text PDF

Previous studies have reported genome-wide mutation profile analyses in ovarian clear cell carcinomas (OCCCs). This study aims to identify specific novel molecular alterations by combined analyses of somatic mutation and copy number variation. We performed whole exome sequencing of 39 OCCC samples with 16 matching blood tissue samples.

View Article and Find Full Text PDF

Advances in next-generation sequencing (NGS) technologies have enabled physicians to test for genomic alterations in multiple cancer-related genes at once in daily clinical practice. In April 2015, we introduced clinical sequencing using an NGS-based multiplex gene assay (OncoPrime) certified by the Clinical Laboratory Improvement Amendment. This assay covers the entire coding regions of 215 genes and the rearrangement of 17 frequently rearranged genes with clinical relevance in human cancers.

View Article and Find Full Text PDF

Osimertinib has been demonstrated to overcome the epidermal growth factor receptor (EGFR)-T790M, the most relevant acquired resistance to first-generation EGFR-tyrosine kinase inhibitors (EGFR-TKIs). However, the C797S mutation, which impairs the covalent binding between the cysteine residue at position 797 of EGFR and osimertinib, induces resistance to osimertinib. Currently, there are no effective therapeutic strategies to overcome the C797S/T790M/activating-mutation (triple-mutation)-mediated EGFR-TKI resistance.

View Article and Find Full Text PDF

Bacillus subtilis is the main component in the fermentation of soybeans. To investigate the genetics of the soybean-fermenting B. subtilis strains and its relationship with the productivity of extracellular poly-γ-glutamic acid (γPGA), we sequenced the whole genome of eight B.

View Article and Find Full Text PDF

De novo microbial genome sequencing reached a turning point with third-generation sequencing (TGS) platforms, and several microbial genomes have been improved by TGS long reads. Bacillus subtilis natto is closely related to the laboratory standard strain B. subtilis Marburg 168, and it has a function in the production of the traditional Japanese fermented food "natto.

View Article and Find Full Text PDF

Proteins in living organisms express various important functions by interacting with other proteins and molecules. Therefore, many efforts have been made to investigate and predict protein-protein interactions (PPIs). Analysis of strengths of PPIs is also important because such strengths are involved in functionality of proteins.

View Article and Find Full Text PDF

Background: To uncover molecular functions and networks in biological cellular systems, it is important to dissect interactions between proteins and RNAs. Many studies have been performed to investigate and analyze interactions between protein amino acid residues and RNA bases. In terms of interactions between residues in proteins, it is generally accepted that an amino acid residue at interacting sites has coevolved together with the partner residue in order to keep the interaction between residues in proteins.

View Article and Find Full Text PDF