Biology subjects

Mizuta, K.

Publications and source records attributed to Mizuta, K..

5 recordsLinked to original sources

bioRxiv2026

BMP-3b suppresses proliferation, migration, invasion, and TGF-β 1/Smad3 signaling in breast cancer cells

ObjectiveBone morphogenetic protein-3b (BMP-3b), also known as growth differentiation factor 10, has been implicated in tumor suppression; however, its role in breast cancer and its interaction with transforming growth factor-{beta}1 (TGF-{beta}1) signaling remain incompletely understood. MethodsPublicly available datasets were used to examine BMP-3b expression in breast lesions and its association with overall survival in patients with stage III or IV breast cancer. Human MCF-7 and murine 4T1 breast cancer cells were treated with recombinant BMP-3b. Cell proliferation, migration, invasion, epithelial-mesenchymal transition-related proteins, and TGF-{beta}1-induced Smad3 phosphorylation were assessed using Cell Counting Kit-8, scratch wound-healing, Transwell invasion, and Western blot assays. ResultsBMP-3b expression was lower in ductal carcinoma in situ than in normal mammary tissue. Low BMP-3b expression was associated with poorer overall survival in patients with stage III or IV breast cancer. BMP-3b reduced proliferation of MCF-7 and 4T1 cells and inhibited migration and invasion of 4T1 cells. BMP-3b increased E-cadherin and decreased vimentin expression in both cell lines. It also attenuated TGF-{beta}1-induced migration, invasion, and Smad3 phosphorylation in 4T1 cells. ConclusionsBMP-3b suppresses malignant phenotypes of breast cancer cells and modulates TGF- {beta}1/Smad3 signaling. These findings identify BMP-3b as a potential endogenous regulator of breast cancer progression.

cell biology↗

bioRxiv2025

A selective top-down pathway from anterior cingulate cortex embeds a representation of saliency in hippocampus

For maximizing survival, animals must accurately memorize the structure of their environment. This is achieved by stabilizing and enriching hippocampal place cells near salient features, while the representation of neutral locations incrementally drifts with time. However, the circuit mechanisms by which top-down and bottom-up inputs selectively embed saliency into the hippocampal spatial map remain poorly understood. Here we identified a specific top-down input from the anterior cingulate cortex (ACC) to the dysgranular zone of the retrosplenial cortex (RSCd) that becomes active exclusively at reward locations. Activity of these ACC neurons is both necessary and sufficient for shaping the hippocampal saliency map. Unlike dopaminergic neurons in the ventral tegmental area, which respond to reward irrespective of the context, this class of ACC neurons encodes reward-context associations. Their optogenetic activation induces a reduction in locomotor speed, a behavioral correlate of saliency detection, while their inhibition disrupts the formation of the hippocampal place map. This work not only provides the first mechanistic insight into how context-dependent saliency is integrated in a top-down fashion into the hippocampal map to guide adaptive behavior but also challenges the classical view of memory consolidation theory where memory unidirectionally moves in bottom-up fashion from the hippocampus to the neocortex.

neuroscience↗

bioRxiv2025

Human fibrosarcoma cells selected for very-high doxorubicin resistance, acquire trabectedin and eribulin cross-resistance, remain sensitive to recombinant methioninase, and have increased c-MYC expression

Doxorubicin is first-line chemotherapy for soft tissue sarcoma; however, the development of drug resistance limits its efficacy. The purpose of the present study was to select very-high doxorubicin-resistant (VHDR) HT1080 fibrosarcoma cells, determine cross-resistance to second-line chemotherapy drugs, determine maintenance of sensitivity to recombinant methioninase (r-METase) alone and in combination with doxorubicin, and measure the level of c-MYC expression. VHDR-HT1080 cells were generated by cultivating HT-1080 cells in a series of step-wise progressively higher concentrations of doxorubicin, ranging from 8 nM to 15 {micro}M, an 1875-fold increase, over a five-month period. The WST-8 reagent was used to assess cell viability. Four groups of in vitro drug-sensitivity tests were conducted, which involved both parental HT1080 and VHDR-HT1080 cells: 1) doxorubicin alone; 2) rMETase alone; 3) a combination of doxorubicin and rMETase; and 4) untreated control. The cross-resistance of VHDR-HT1080 cells to eribulin, trabectedin, gemcitabine and docetaxel was determined. The c-MYC levels in HT1080 and VHDR-HT1080 cells were measured using Western blotting. Doxorubicin had an IC50 of 3.3 {micro}M against HT1080 cells and 38.2 {micro}M against VHDR-HT1080 cells an 11.6-fold increase. The rMETase IC50 value for HT1080 was 0.75 U/ml and 0.59 U/ml for VHDR-HT1080. rMETase sensitized VHDR-HT1080 cells to doxorubicin. VHDR-HT1080 cells were cross-resistant to trabectedin 8.9-fold and cross-resistant to eribulin 1.87-fold compared to parental HT1080 cells. c-MYC expression was 8.4 times higher in VHDR-HT1080 cells compared to HT-1080 cells. The present results suggest rMETase may be used as a future clinical strategy to overcome super-doxorubicin resistance in soft tissue sarcoma.

cancer biology↗

bioRxiv2024

Atlas of Cynomolgus Macaque Hematopoiesis

Self-renewal and differentiation are inherent properties of hematopoietic stem cells (HSCs) that are necessary to support hematopoiesis; however, the underlying mechanisms, especially in human, remain unclear. Here, using the cynomolgus macaque as a surrogate model, we develop a new gating strategy to isolate with high purity transplantable cynomolgus HSCs and generated a single-cell transcriptomic map of cynomolgus HSCs and progenitor cells -- that covering gestational periods previously not analyzed in human. We show that hematopoietic cells from the late-1st to early-3rd trimester fetal liver and late-2nd trimester and thereafter bone marrow have repopulating potential, closely mimicking humans. Unexpectedly however, we found unlike in human, cynomolgus HSCs express CD38 but not CD33, indicating that these cellular counterparts are molecularly distinct. Our transcriptomic analysis reveals the presence of a direct differentiation pathway from HSCs to megakaryocyte lineages, lineage-primed multipotent progenitors and also identified putative HSC surface markers. Taken together, our comprehensive dataset highlights not only the utility of cynomolgus monkeys as model systems to study hematopoiesis but also their potential for translational applications.

cell biology↗

bioRxiv2018

Dynamic embedding of salience coding in hippocampal spatial maps

Hippocampal CA1 neurons participate in dynamic ensemble codes for space and memory. Prominent features of the environment are represented by an increased density of place cells, but cellular principles governing the formation and plasticity of such disproportionate maps are unknown. We thus imaged experience-dependent long-term changes in spatial representations at the cellular level in the CA1 deep sublayer in mice learning to navigate in a virtual-reality environment. The maps were highly dynamic but gradually stabilized as over-representations for motivational (reward) and environmental (landmark) salience emerged in different time courses by selective consolidation of relevant spatial representations. Relocation of the reward extensively reorganized pre-formed maps by a mechanism involving rapid recruitment of cells from the previous location followed by their re-stabilization, indicating that a subset of neurons encode reward-related information. The distinct properties of these CA1 cells may provide a substrate by which salient experience forms lasting and adaptable memory traces.

neuroscience↗