Neuroendocrine cells orchestrate regeneration through Desert hedgehog signaling.

Understanding the mechanisms underlying mammalian regeneration may enable development of novel regenerative therapies. We present a mechanism wherein Desert hedgehog (Dhh), secreted from epithelial neuroendocrine cells, elicits a regenerative/protective response from mesenchymal cells. In mammalian airway, this mesenchymal response strikingly amplifies the initial signal from rare neuroendocrine cells to activate the entire tissue for survival and regeneration upon injury from SO gas inhalation or following influenza or SARS-CoV-2 infection.

Generation of prostate cancer assembloids modeling the patient-specific tumor microenvironment.

Prostate cancer (PC) is the most frequently diagnosed malignancy among men and contributes significantly to cancer-related mortality. While recent advances in in vitro PC modeling systems have been made, there remains a lack of robust preclinical models that faithfully recapitulate the genetic and phenotypic characteristics across various PC subtypes-from localized PC (LPC) to castration-resistant PC (CRPC)-along with associated stromal cells. Here, we established human PC assembloids from LPC and CRPC tissues by reconstituting tumor organoids with corresponding cancer-associated fibroblasts (CAFs), thereby incorporating aspects of the tumor microenvironment (TME).

-targeted, stable expression of ChR2 in human brain organoids for consistent optogenetic control.

Self-organizing brain organoids provide a promising tool for studying human development and disease. Here we created human forebrain organoids with stable and homogeneous expression of channelrhodopsin-2 (ChR2) by generating safe harbor locus-targeted, ChR2 knocked-in human pluripotent stem cells (hPSCs), followed by the differentiation of these genetically engineered hPSCs into forebrain organoids. The resulting ChR2-expressing human forebrain organoids showed homogeneous cellular expression of ChR2 throughout entire regions without any structural and functional perturbations and displayed consistent and robust neural activation upon light stimulation, allowing for the non-virus mediated, spatiotemporal optogenetic control of neural activities.

Melatonin alleviates myocardial dysfunction through inhibition of endothelial-to-mesenchymal transition via the NF-κB pathway.

Endothelial-to-mesenchymal transition (EndMT) is a complex biological process of cellular transdifferentiation by which endothelial cells (ECs) lose their characteristics and acquire mesenchymal properties, leading to cardiovascular remodeling and complications in the adult cardiovascular diseases environment. Melatonin is involved in numerous physiological and pathological processes, including aging, and has anti-inflammatory and antioxidant activities. This molecule is an effective therapeutic candidate for preventing oxidative stress, regulating endothelial function, and maintaining the EndMT balance to provide cardiovascular protection.

A new era of stem cell and developmental biology: from blastoids to synthetic embryos and beyond.

Recent discoveries in stem cell and developmental biology have introduced a new era marked by the generation of in vitro models that recapitulate early mammalian development, providing unprecedented opportunities for extensive research in embryogenesis. Here, we present an overview of current techniques that model early mammalian embryogenesis, specifically noting models created from stem cells derived from two significant species: Homo sapiens, for its high relevance, and Mus musculus, a historically common and technically advanced model organism. We aim to provide a holistic understanding of these in vitro models by tracing the historical background of the progress made in stem cell biology and discussing the fundamental underlying principles.

Stem cells, organoids and their applications for human diseases: Special issue of BMB Reports in 2023.

Studying human biology has been challenging with conventional animal models or two-dimensional (2D) cultured cell lines. Recent advances in stem cell biology have made it possible to culture stem cells in vitro, leading to the establishment of in vitro three-dimensional (3D) organ-like structures known as organoids. Organoids are self-organizing 3D miniature tissues that mimic the tissue architecture and functionality of in vivo counterparts.

Network-based machine learning approach to predict immunotherapy response in cancer patients.

Immune checkpoint inhibitors (ICIs) have substantially improved the survival of cancer patients over the past several years. However, only a minority of patients respond to ICI treatment (~30% in solid tumors), and current ICI-response-associated biomarkers often fail to predict the ICI treatment response. Here, we present a machine learning (ML) framework that leverages network-based analyses to identify ICI treatment biomarkers (NetBio) that can make robust predictions.

Production of Recombinant Active Human TGFβ1 in .

The production of recombinant proteins in plant systems is receiving wider attention. Indeed, various plant-produced pharmaceuticals have been shown to be biologically active. However, the production of human growth factors and cytokines in heterologous systems is still challenging because they often act as complex forms, such as homo- or hetero-dimers, and their production is tightly regulated .

Creation of bladder assembloids mimicking tissue regeneration and cancer.

Current organoid models are limited by their inability to mimic mature organ architecture and associated tissue microenvironments. Here we create multilayer bladder 'assembloids' by reconstituting tissue stem cells with stromal components to represent an organized architecture with an epithelium surrounding stroma and an outer muscle layer. These assembloids exhibit characteristics of mature adult bladders in cell composition and gene expression at the single-cell transcriptome level, and recapitulate in vivo tissue dynamics of regenerative responses to injury.

Network-based machine learning in colorectal and bladder organoid models predicts anti-cancer drug efficacy in patients.

Cancer patient classification using predictive biomarkers for anti-cancer drug responses is essential for improving therapeutic outcomes. However, current machine-learning-based predictions of drug response often fail to identify robust translational biomarkers from preclinical models. Here, we present a machine-learning framework to identify robust drug biomarkers by taking advantage of network-based analyses using pharmacogenomic data derived from three-dimensional organoid culture models.

Use of inkjet-printed single cells to quantify intratumoral heterogeneity.

Quantification of intratumoral heterogeneity is essential for designing effective therapeutic strategies in the age of personalized medicine. In this study, we used a piezoelectric inkjet printer to enable analysis of intratumoral heterogeneity in a bladder cancer for the first time. Patient-derived tumor organoids were dissociated into single cell suspension and used as a bioink.

Removal of N-Terminal Fusion Domains From Recombinant Target Proteins Produced in .

Plants show great potential for producing recombinant proteins in a cost-effective manner. Many strategies have therefore been employed to express high levels of recombinant proteins in plants. Although foreign domains are fused to target proteins for high expression or as an affinity tag for purification, the retention of foreign domains on a target protein may be undesirable, especially for biomedical purposes.

Culture, Manipulation, and Orthotopic Transplantation of Mouse Bladder Tumor Organoids.

The development of advanced tumor models has long been encouraged because current cancer models have shown limitations such as lack of three-dimensional (3D) tumor architecture and low relevance to human cancer. Researchers have recently developed a 3D in vitro cancer model referred to as tumor organoids that can mimic the characteristics of a native tumor in a culture dish. Here, experimental procedures are described in detail for the establishment of bladder tumor organoids from a carcinogen-induced murine bladder tumor, including culture, passage, and maintenance of the resulting 3D tumor organoids in vitro.

Stromal activity coordinates a niche signaling program for mammary epithelial stem cells.

The stem cell niche is a complex local signaling microenvironment that sustains stem cell activity during organ maintenance and regeneration. The mammary gland niche must support its associated stem cells while also responding to systemic hormonal regulation that triggers pubertal changes. We find that , the major Hedgehog pathway transcriptional effector, acts within mouse mammary stromal cells to direct a hormone-responsive niche signaling program by activating expression of factors that regulate epithelial stem cells as well as receptors for the mammatrophic hormones estrogen and growth hormone.

Control of inflammation by stromal Hedgehog pathway activation restrains colitis.

Inflammation disrupts tissue architecture and function, thereby contributing to the pathogenesis of diverse diseases; the signals that promote or restrict tissue inflammation thus represent potential targets for therapeutic intervention. Here, we report that genetic or pharmacologic Hedgehog pathway inhibition intensifies colon inflammation (colitis) in mice. Conversely, genetic augmentation of Hedgehog response and systemic small-molecule Hedgehog pathway activation potently ameliorate colitis and restrain initiation and progression of colitis-induced adenocarcinoma.

Spatially restricted Hedgehog signalling regulates HGF-induced branching of the adult prostate.

Branching morphogenesis is thought to be governed by epithelial-stromal interactions, but the mechanisms underlying specification of branch location remain largely unknown. Prompted by the striking absence of Hedgehog (Hh) response at the sites of nascent buds in regenerating tubules of the adult prostate, we investigated the role of Hh signalling in adult prostate branching morphogenesis. We find that pathway activity is localized to stromal cells, and that its attenuation by genetic or pharmacologic manipulation leads to increased branching.

Hedgehog signaling restrains bladder cancer progression by eliciting stromal production of urothelial differentiation factors.

Hedgehog (Hh) pathway inhibitors are clinically effective in treatment of basal cell carcinoma and medulloblastoma, but fail therapeutically or accelerate progression in treatment of endodermally derived colon and pancreatic cancers. In bladder, another organ of endodermal origin, we find that despite its initial presence in the cancer cell of origin Sonic hedgehog (Shh) expression is invariably lost during progression to invasive urothelial carcinoma. Genetic blockade of stromal response to Shh furthermore dramatically accelerates progression and decreases survival time.

Cellular origin of bladder neoplasia and tissue dynamics of its progression to invasive carcinoma.

Understanding how malignancies arise within normal tissues requires identification of the cancer cell of origin and knowledge of the cellular and tissue dynamics of tumour progression. Here we examine bladder cancer in a chemical carcinogenesis model that mimics muscle-invasive human bladder cancer. With no prior bias regarding genetic pathways or cell types, we prospectively mark or ablate cells to show that muscle-invasive bladder carcinomas arise exclusively from Sonic hedgehog (Shh)-expressing stem cells in basal urothelium.

Hedgehog/Wnt feedback supports regenerative proliferation of epithelial stem cells in bladder.

Epithelial integrity in metazoan organs is maintained through the regulated proliferation and differentiation of organ-specific stem and progenitor cells. Although the epithelia of organs such as the intestine regenerate constantly and thus remain continuously proliferative, other organs, such as the mammalian urinary bladder, shift from near-quiescence to a highly proliferative state in response to epithelial injury. The cellular and molecular mechanisms underlying this injury-induced mode of regenerative response are poorly defined.

Mechanosensitive hair cell-like cells from embryonic and induced pluripotent stem cells.

Mechanosensitive sensory hair cells are the linchpin of our senses of hearing and balance. The inability of the mammalian inner ear to regenerate lost hair cells is the major reason for the permanence of hearing loss and certain balance disorders. Here, we present a stepwise guidance protocol starting with mouse embryonic stem and induced pluripotent stem cells, which were directed toward becoming ectoderm capable of responding to otic-inducing growth factors.

PATJ regulates directional migration of mammalian epithelial cells.

Directional migration is important in wound healing by epithelial cells. Recent studies have shown that polarity proteins such as mammalian Partitioning-defective 6 (Par6), atypical protein kinase C (aPKC) and mammalian Discs large 1 (Dlg1) are crucial not only for epithelial apico-basal polarity, but also for directional movement. Here, we show that the protein associated with Lin seven 1 (PALS1)-associated tight junction protein (PATJ), another evolutionarily conserved polarity protein, is also required for directional migration by using a wound-induced migration assay.

ZOning out tight junctions.

The tight junction is an intricate seal between adjoining epithelial cells that also separates the apical and basolateral membranes within these cells. A paper in this issue of Cell by Umeda et al. (2006) demonstrates that loss of the ZO scaffolding proteins prevents the formation of tight junctions but surprisingly does not perturb apico-basal polarity.