Biology subjects

Kurita, T.

Publications and source records attributed to Kurita, T..

5 recordsLinked to original sources

bioRxiv2022

Patient-derived xenograft studies of fumarate hydratase (FH) -deficient uterine leiomyoma subtype.

Uterine leiomyoma (LM) is the most common benign gynecological tumor in premenopausal women. Our previous patient-derived xenograft (PDX) studies established that 17{beta}-estradiol (E2) and progesterone (P4) stimulate the growth of the two most prevalent subtypes, MED12 mutant (MED12-LM) and HMGA2 overexpressing LMs (HMGA2-LM), via proliferation and hypertrophy of smooth muscle tumor cells (SMTCs). In addition, tumor-associated fibroblasts (TAFs) that do not carry MED12 mutations also contribute to the growth of MED12-LM by secreting extracellular matrix (ECM) proteins. In this study, we investigated the growth control of the fumarate hydratase (FH) deficient LM (FH-LM) subtype, utilizing the PDX model. We identified an FH-negative case with conventional leiomyoma histology. The overexpression of aldo-keto reductase family 1 member B10 (AKR1B10) confirmed the FH deficiency. Like MED12-LM, FH-LM comprised two major cell types: 54.4% SMTCs and 43.3% TAFs. Furthermore, the TAFs expressed FH. The FH-LM PDXs grew in response to E2 and P4 via proliferation and hypertrophy of SMTCs, similar to MED12-LM and HMGA2-LM. While E2 alone did not stimulate growth, E2 was essential for sensitizing FH-deficient SMTCs to P4 by upregulating progesterone receptor (PGR). Our current study established that the growth of the three most prevalent LM subtypes, MED12-LM, HMGA2-LM, and FH-LM, depends on E2 and P4. Thus, selective progesterone receptor modulators (SPRMs) should be an effective treatment option for most symptomatic LM patients.

genetics↗

bioRxiv2021

Development and evaluation of PCR primers for environmental DNA (eDNA) metabarcoding of Amphibia

Biodiversity monitoring is important for the conservation of natural ecosystems in general, but particularly for amphibians, whose populations are pronouncedly declining. However, amphibians ecological traits (e.g., nocturnal or aquatic) often prevent their precise monitoring. Environmental DNA (eDNA) metabarcoding--analysis of extra-organismal DNA released into the environment--allows the easy and effective monitoring of the biodiversity of aquatic organisms. Here, we developed and tested the utility of original PCR primer sets. First, we conducted in vitro PCR amplification tests with universal primer candidates using total DNA extracted from amphibian tissues. Five primer sets successfully amplified the target DNA fragments (partial 16S rRNA gene fragments of 160-311 bp) from all 16 taxa tested (from the three living amphibian orders Anura, Caudata, and Gymnophiona). Next, we investigated the taxonomic resolution retrieved using each primer set. The results revealed that the universal primer set "Amph16S" had the highest resolution among the tested sets. Finally, we applied Amph16S to actual metabarcoding and evaluated its detection capability by comparing the species detected using eDNA and physical survey (capture-based sampling and visual survey) in multiple agricultural ecosystems across Japan (160 sites in 10 areas). The eDNA metabarcoding with Amph16S detected twice as many species as the physical surveys (16 vs. 8 species, respectively), indicating the effectiveness of Amph16S in biodiversity monitoring and ecological research for amphibian communities.

ecology↗

bioRxiv2020

Stage-specific muscle wasting mechanisms in a novel cancer cachexia mouse model for ovarian granulosa cell tumor

Cachexia is a progressive muscle wasting syndrome that increases mortality risk in cancer patients, while there are still no effective treatment due to the complexity of syndrome and the lack of preclinical models. We identified a transgenic mice model with ovarian granulosa cell tumors mimic the progression of cachexia seen in humans, including drastic weight loss, skeletal muscle wasting and increased serum cachexia biomarker activin A and GDF15. Hypercatabolism was detected in skeletal muscle, having upregulation of E3 ligases Atrogin-1 and Murf-1. Our cachexia model exhibited stage-specific muscle wasting mechanisms. At precachexia stage, elevation of activin A activates p38 MAPK. Inhibition of activin A with Follistatin reversed weight loss at precachexia stage. At cachexia stage, energy stress in skeletal muscle activates AMPK and leads to upregulation of FoxO3. Our results indicate this novel preclinical cancer cachexia model is exploitable for studying pathophysiological mechanisms and testing therapeutic agents of cachexia.

cancer biology↗

bioRxiv2020

In silico prediction of ARB resistance: A first step in creating personalized ARB therapy

Angiotensin II type 1 receptor (AT1R) blockers (ARBs) are among the most prescribed drugs. However, ARB effectiveness varies widely, and some patients do not respond to ARB therapy. One reason for the variability between patients is non-synonymous single nucleotide polymorphisms (nsSNPs) within agtr1, the AT1R gene. There are over 100 nsSNPs in the AT1R; therefore, this study embarked on determining which nsSNPs may abrogate the binding of selective ARBs. The crystal structure of olmesartan-bound human AT1R (PDB:4ZUD) served as a template to create an inactive empty AT1R via molecular dynamics simulation (n = 3). All simulations resulted in a smaller ligand-binding pocket than 4ZUD due to the absence of olmesartan in the simulation yet remained inactive with little movement in the receptor core. A single frame representing the average stable AT1R was used as a template to thrice (n = 3) dock each ARB via AutoDock to obtain a predicted affinity from the weighted average of 100 docking simulations. The results were far from known values; thus, an optimization protocol was initiated, resulting in the predicted binding affinities within experimentally determined ranges (n = 6). The empty model AT1R was altered and minimized in Molecular Operating Environment software to represent 103 of the known human AT1R polymorphisms. Each of the eight ARBs was then docked, using the optimized parameters, to each polymorphic AT1R (n = 6). Although each nsSNP has little effect on global AT1R structure, most nsSNPs drastically alter a sub-set of ARBs affinity to the AT1R. Comparisons to previous binding studies suggest that the results have a 60% chance of predicting ARB resistance. Although more biochemical studies and refinement of the model are required to increase the accuracy of the prediction of ARB resistance, personalized ARB therapy based on agtr1 sequence could increase overall ARB effectiveness. Author SummaryThe term "personalized medicine" was coined at the turn of the century, but most medicines are currently prescribed based on disease categories and occasionally racial demographics, but not personalized attributes. In cardiovascular medicine, the personalization of medication is minimal; however, it is accepted that not all patients respond equally to common cardiovascular medications. Here we chose one prominent cardiovascular drug target, the angiotensin receptor, and, using computer modeling, created preliminary models of over 100 known alterations to the angiotensin receptor to determine if the alterations changed the ability of clinically used drugs to interact with the angiotensin receptor. The strength of interaction was compared to the unaltered angiotensin receptor, generating a map predicting which alteration affected each drug. It is expected that in the future, a patients receptors can be sequenced, and maps, such as the one presented here, can be used to select the optimum medication based on the patients genetics. Such a process would allow for the personalization of current medication therapy.

pharmacology and toxicology↗

bioRxiv2018

SIX1 cooperates with RUNX1 and SMAD4 in cell fate commitment of Müllerian duct epithelium

During female mammal reproductive tract development, epithelial cells of the lower Mullerian duct are committed to become stratified squamous epithelium of vagina and ectocervix, when the expression of {Delta}Np63 transcription factor is induced by mesenchymal cells. The absence of {Delta}Np63 expression leads to adenosis, the putative precursor of vaginal adenocarcinoma. Our previous studies with genetically engineered mouse models have established that fibroblast growth factor (FGF)/mitogen-activated protein kinase (MAPK), bone morphogenetic protein (BMP)/SMAD, and activin A/runt related transcription factor 1 (RUNX1) signaling pathways are independently required for {Delta}Np63 expression in Mullerian duct epithelium (MDE). Here we report that sine oculis homeobox homolog 1 (SIX1) plays a critical role in the activation of {Delta}Np63 locus in MDE as a downstream transcription factor of mesenchymal signals. In mouse developing reproductive tract, SIX1 expression was restricted to MDE of the future cervix and vagina. SIX1 expression was totally absent in SMAD4 null MDE and was reduced in RUNX1 null and FGFR2 null MDE, indicating that SIX1 is under the control of vaginal mesenchymal factors, BMP4, activin A and FGF7/10. Furthermore, Six1, Runx1 and Smad4 gene-dose-dependently activated {Delta}Np63 expression in MDE within vaginal fornix. Using a mouse model of diethylstilbestrol (DES)-associated vaginal adenosis, we found DES action through epithelial estrogen receptor (ESR1) down-regulates SIX1 and RUNX1 in MDE within the vaginal fornix. This study establishes that the vaginal/ectocervical cell fate of MDE is regulated by a collaboration of multiple transcription factors including SMAD4, SIX1 and RUNX1, and the down-regulation of these key transcription factors leads to vaginal adenosis.\n\nAuthor SummaryIn embryogenesis, differentiation fate of cells is specified through constant communication between neighboring cells. In this study, we investigated the molecular mechanism of epithelial cell fate commitment in the lower female reproductive organs utilizing mouse genetic models. The cell fate of epithelial cells in the uterus, cervix and vagina is directed by signaling from mesenchymal cells. We demonstrated that within the epithelial cells of the developing vagina, signals from mesenchymal cells are integrated into activities of transcription factors including SMAD4, RUNX1 and SIX1, which dose-dependently co-operate in the determination of vaginal epithelial cell fate. Disruption of these processes alters the cell fate from vaginal to uterine epithelium, resulting in a condition called vaginal adenosis, a putative precursor of vaginal adenocarcinoma. Women exposed to diethylstilbestrol (DES) in the womb have about 40 times the risk of developing vaginal adenocarcinoma. We determined that developmental exposure to DES induces vaginal adenosis by repressing SIX1 and RUNX1 through ESR1 in the epithelial cells. This discovery enhances the understanding of how early-life events, such as exposure to endocrine disruptors, causes vaginal adenosis, and thus may contribute to the prevention and therapeutic treatment of idiopathic vaginal adenocarcinoma.

developmental biology↗