Deep learning technology has recently achieved significant breakthroughs in cell detection, e.g., cervical cancer or neural cells. While current methods primarily rely on ImageNet-pretrained visual backbones and conventional detection frameworks, their performance remains suboptimal. Vision-language model (VLM)-based detectors, which leverage large-scale pretraining and process both textual and visual inputs to achieve cross-modal semantic alignment, have significantly advanced cell detection accuracy. However, unlike common objects, cell data exhibits frequent instances of various morphologies within the same cell and morphological similarities across different cells, which may lead to different cells with similar shapes being distributed very closely in the visual feature space. This confused distribution between visual features ultimately impairs the VLM-based detector’s capacity to establish accurate cross-modal associations, resulting in classification confusion. To solve this issue, we propose a plug-and-play Contrastive Proposal Alignment (CPA) module that enhances VLM-based detectors by refining visual feature distributions in the embedding space. Specifically, we first filter reliable predicted proposals against ground-truth boxes, then employ supervised contrastive loss to cluster same-category cell proposals despite different shapes, while pushing apart embeddings from different cell classes within the feature space, thereby avoiding incorrect visual feature distribution. Extensive experiments on cervical and neural cell detection datasets show that our proposed CPA module can assist the VLM-based detector to mitigate cross-modal semantic bias and improve cell detection performance.

BACKGROUND & AIMS:Hedgehog signaling plays a complex role in epithelial-stromal interactions, but its effects on gastrointestinal stem cells mediated by heterogeneous stromal cell populations remain incompletely defined. Here, we investigate how stromal Hedgehog signaling regulates gastric stem cells and tumorigenesis in a segment-specific manner. METHODS:We genetically activated Hedgehog signaling in distinct stromal cell lineages using Col1a2-, Pdgfra-, Gli1-, Acta2-, and Prrx1-CreERT mouse lines, combined with lineage tracing, RNA sequencing, chromatin immunoprecipitation-quantitative polymerase chain reaction, and pharmacologic interventions. Human gastric cancer data from The Cancer Genome Atlas were also analyzed. RESULTS:We show that genetic activation of Hedgehog signaling in stromal cells marked by Col1a2, Pdgfra, or Gli1, but not by Acta2, induces tumorigenesis in the stomach and gastroesophageal junction, but not in the small or large intestine. Hedgehog signaling increases the expression of multiple bone morphogenetic protein antagonists in gastric but not colonic stromal cells, via Gli1-mediated transcription. These bone morphogenetic protein antagonists, in turn, activate Wnt/β-catenin signaling in gastric stem cells, driving their proliferation and initiating gastric cancer expressing CD44 and Sox9, but not Lgr5. Activating bone morphogenetic protein or inhibiting Wnt signaling blocks tumor initiation. Analysis of patient data from The Cancer Genome Atlas reveals elevated Hedgehog signaling in gastric cancers, which correlates with suppressed bone morphogenetic protein signaling. CONCLUSIONS:These findings uncover a gastrointestinal segment-specific oncogenic role for Hedgehog signaling in Col1a2+Acta2- stromal cells, mediated through the bone morphogenetic protein-Wnt-β-catenin axis.

The repair of corneal injuries remains a major challenge in clinical practice. Impaired corneal wound healing is closely associated with aberrantly activated stromal keratocytes and disorganized extracellular matrix. Here, we identify aberrant Hedgehog signaling in corneal keratocytes as a key driver of defective wound repair. In adult mice, Hedgehog signaling is suppressed in quiescent keratocytes but is pathologically reactivated following chemical injury, correlating with impaired repair. Keratocyte-specific Hedgehog activation via Ptch1 ablation disrupted corneal wound healing after epithelial scraping—a process that would normally resolve seamlessly under physiological conditions. Mechanistically, Hedgehog activation induced stromal thinning and stiffening through disorganized collagen fibrils. Transcriptomics analysis revealed keratocyte transdifferentiation into fibroblast-like phenotypes, accompanied by downregulation of extracellular matrix genes. Hedgehog-mediated stromal stiffening suppressed YAP activity in the overlying epithelium via Hippo pathway activation, blocking epithelial differentiation—a defect that was reversed by Hippo inhibition (XMU-MP-1). In chemical injury models, genetic Smo deletion or pharmacological Gli1/2 inhibition (GANT61) restored stromal architecture, normalized collagen organization, and rescued epithelial differentiation defects. These findings establish Hedgehog signaling in keratocytes as a critical regulator of stromal–epithelial crosstalk and highlight its targeted inhibition as a potential therapeutic strategy to restore corneal transparency and repair fidelity after injury.

Cellular communication network factor 2 (CCN2) is a secreted extracellular matrix-associated protein, and its aberrantly increased expression has been implicated in a diversity of diseases involving pathological processes of fibrosis, chronic inflammation, or tissue injury, which has promoted the evaluation of CCN2 as therapeutic targets for multiple disorders. However, human phenotypes associated with CCN2 deficiency have remained enigmatic; variants in CCN2 have not yet been associated with a human phenotype. Here, we collected families diagnosed with spondyloepimetaphyseal dysplasia (SEMD), and screened candidate pathogenic genes for families without known genetic causes using next-generation sequencing. We identified a monoallelic variant in signal peptide of CCN2 (NM_001901.2: c.65 G > C [p.Arg22Pro]) as the cause of SEMD in 14 subjects presenting with different degree of short stature, premature osteoarthritis, and osteoporosis. Affected subjects showed decreased serum CCN2 levels. Cell lines harboring the variant displayed decreased amount of CCN2 proteins in culture medium and an increased intracellular retention, indicating impaired protein secretion. And the variant weakened the stimulation effect of CCN2 on osteogenesis of bone marrow mesenchymal stem cells. Zebrafish ccn2a knockout model and osteoblast lineage-specific Ccn2-deficient mice (Ccn2fl/fl;Prx1Cre) partially recapitulated the phenotypes including low bone mass observed in affected subjects. Pathological mechanism implicated in the skeletal abnormality in Ccn2fl/fl;Prx1Cre mice involved decreased bone formation, increased bone resorption, and abnormal growth plate formation. Collectively, our study indicate that monoallelic variants in CCN2 lead to a human inherited skeletal dysplasia, and highlight the critical role of CCN2 in osteogenesis in human.

Specialized connective tissues, including bone and adipose tissues, control various physiological activities, including mineral and energy homeostasis. However, the identity of stem cells maintaining these tissues throughout adulthood remains elusive. By conducting genetic lineage tracing and cell depletion experiments in newly generated knock-in Cre/CreER T2 lines, we show here that rare Prrx1 -expressing cells act as stem cells for bone, white adipose tissue and dermis in adult mice, which are indispensable for the homeostasis and repair of these tissues. Single-cell profiling reveals the cycling and multipotent nature of Prrx1 -expressing cells and the stemness of these cells is further validated by transplantation assays. Moreover, we identify the cell surface markers for Prrx1 -expressing stem cells and show that the activities of these stem cells are regulated by Wnt signaling. These findings expand our knowledge of connective tissue homeostasis/regeneration and may help improve stem-cell-based therapies.

The cornea fends off chemicals, dirt, and infectious particles and provides most of the eye's focusing power. Corneal transparency is of paramount importance to normal vision, yet how it is established and maintained remains unclear. Here, we ablated Notch1 in keratocytes using Twist2-Cre mice and found that Twist2-Cre; Notch1f/f mice developed stroma expansion and neovascularization, followed by hyperproliferation and metaplasia of corneal epithelial progenitor cells and plaque formation at central cornea, leading to loss of transparency. Development of these phenotypes does not involve bacteria-caused inflammation; instead, Notch1 deletion upregulates Vegfa and Vegfc via Hif1α in keratocytes. Vascular endothelial growth factor (VEGF) receptor inhibitor axitinib prevented development of these anomalies in Twist2-Cre; Notch1f/f mice, suggesting that VEGFs secreted by keratocytes promote not only neovascularization but also proliferation and metaplasia of epithelial progenitor cells at central cornea. This study uncovers a Notch1-Hif1α-VEGF pathway in keratocytes that maintains corneal transparency and represents a potential target for treatment of related corneal disorders.

NF‐κB is known to be implicated in skeletal development and related diseases. Previous studies have shown that RelA, a key subunit of NF‐κB, is involved in osteoblast and chondrocyte survival and differentiation. Yet, the physiological roles of RelA in mesenchymal stem cells (MSCs), which give rise to both chondrocytes and osteoblasts, are still poorly understood. Here, we generated Prrx1‐Cre;RelAf/f mice to delete RelA in Prrx1+ bone marrow MSCs and found that RelA deletion led to decreased MSC proliferation and altered differentiation, with increased osteogenic and chondrogenic differentiation but decreased adipogenic differentiation. Bone size and mass were not significantly changed in the mutant mice, although they developed moderate osteoarthritis‐like phenotypes. Thus, our studies reveal important but discordant functions of RelA in MSC proliferation and differentiation, and provide an explanation why MSC‐specific RelA knockout mice only develop minor skeletal phenotypes.

背景:肝素结合表皮生长因子样生长因子对骨骼的发育十分重要,但目前尚未报道过体内骨髓间充质干细胞来源的肝素结合表皮生长因子样生长因子对骨发育的影响.目的:探究在骨髓间充质干细胞中过表达肝素结合表皮生长因子样生长因子对骨发育的影响并初步分析相关机制.方法:利用 Cre-LoxP 系统构建在 Prrx1+骨髓间充质干细胞中过表达肝素结合表皮生长因子样生长因子(ROSA26tm1(HB-EGF); Prrx1-Cre)的小鼠模型,取骨组织切片染色进行组织学分析.取小鼠骨髓间充质干细胞进行体外培养,进行分化能力检测和分子机制研究.实验于2015年经上海交通大学实验动物管理、学术、伦理与使用委员会批准,批准号为A2015027.结果和结论:①Prrx1在成年小鼠股骨关节头、生长板、骨小梁表面和骨膜上均有表达;②ROSA26tm1(HB-EGF);Prrx1-Cre小鼠股骨变短,骨量明显减少,软骨形态和结构异常,出现骨关节炎样表型;③ROSA26tm1(HB-EGF);Prrx1-Cre小鼠骨髓间充质干细胞体外成骨、软骨分化减弱.结果提示在骨髓间充质干细胞中过表达HB-EGF可能通过削弱骨髓间充质干细胞成骨、软骨分化抑制小鼠骨发育.

Indian Hedgehog (IHH) signaling, a key regulator of skeletal development, is highly activated in cartilage and bone tumors. Yet deletion of Ptch1, encoding an inhibitor of IHH receptor Smoothened (SMO), in chondrocyte or osteoblasts does not cause tumorigenesis. Here, we show that Ptch1 deletion in mice Prrx1+mesenchymal stem/stromal cells (MSCs) promotes MSC proliferation and osteogenic and chondrogenic differentiation but inhibits adipogenic differentiation. Moreover, Ptch1 deletion led to development of osteoarthritis-like phenotypes, exostoses, enchondroma, and osteosarcoma in Smo-Gli1/2-dependent manners. The cartilage and bone tumors are originated from Prrx1+ lineage cells and express low levels of osteoblast and chondrocyte markers, respectively. Mechanistically, Ptch1 deletion increases the expression of Wnt5a/6 and leads to enhanced β-Catenin activation. Inhibiting Wnt/β-Catenin pathway suppresses development of skeletal anomalies including enchondroma and osteosarcoma. These findings suggest that cartilage/bone tumors arise from their early progenitor cells and identify the Wnt/β-Catenin pathway as a pharmacological target for cartilage/bone neoplasms.

The bronchiole is a major site for the development of several life-threatening disorders, including chronic obstructive pulmonary disease and lung adenocarcinomas. The bronchiolar epithelium is composed of club cells and ciliated epithelial cells, with club cells serving as progenitor cells. Presently, the identity of the cells involved in regeneration of bronchiolar epithelium and the underlying mechanisms remain incompletely understood. Here, we show that Prrx1, a homeobox transcription factor, can mark club cells in adult mice during homeostasis and regeneration. We further show that the noncanonical signaling pathway of BMPs, BMPR1A-Tak1-p38MAPK, plays a critical role in club cell regeneration. Ablation of Bmpr1a, Tak1, or Mapk14 (encoding p38α) in Prrx1+ club cells caused minimal effect on bronchiolar epithelium homeostasis, yet it resulted in severe defects in club cell regeneration and bronchiole repair in adult mice. We further show that this pathway supports proliferation and expansion of the regenerating club cells. Our findings thus identify a marker for club cells and reveal a critical role for the BMP noncanonical pathway in club cell regeneration.

Bone morphogenetic proteins (BMPs) activate the canonical Smad1/5/8 and non-canonical Tak1-MAPK pathways via BMP receptors I and II to regulate skeletal development and bone remodeling. Specific ablation of Bmpr1a in immature osteoblasts, osteoblasts, or osteocytes results in an increase in cancellous bone mass, yet opposite results have been reported regarding the underlying mechanisms. Moreover, the role for BMPRIA-mediated signaling in bone marrow mesenchymal stromal cells (BM-MSCs) has not been explored. Here, we specifically ablated Bmpr1a in BM-MSCs in adult mice to study the function of BMPR1A in bone remodeling and found that the mutant mice showed an increase in cancellous and cortical bone mass, which was accompanied by a decrease in bone formation rate and a greater decrease in bone resorption. Decreased bone formation was associated with a defect in BM-MSC osteogenic differentiation whereas decreased bone resorption was associated with a decrease in RANKL production and osteoclastogenesis. However, ablation of Tak1, a critical non-canonical signaling molecule downstream of BMP receptors, in BM-MSCs at adult stage did not affect bone remodeling. These results suggest that BMP signaling through BMPRIA controls BM-MSC osteogenic differentiation/bone formation and RANKL expression/osteoclastogenesis in adult mice independent of Tak1 signaling.

ABSTRACT HB-EGF, a member of the EGF superfamily, plays important roles in development and tissue regeneration. However, its functions in skeletal stem cells and skeleton development and growth remain poorly understood. Here, we used the Cre/LoxP system to ablate or express HB-EGF in Dermo1+ mesenchymal stromal cells and their progenies, including chondrocytes and osteoblast lineage cells, and bone marrow stromal cells (BMSCs). Dermo1-Cre; HB-EGFf/f mice only showed a modest increase in bone mass, whereas Dermo1-HB-EGF mice developed progressive chondrodysplasia, chondroma, osteoarthritis-like joint defects, and loss of bone mass and density, which were alleviated by treatment with EGFR inhibitor AG1478. The cartilage defects were recapitulated in chondrocyte-specific HB-EGF overexpression (Col2-HB-EGF) mice with a lesser severity. Dermo1-HB-EGF mice showed an increase in proliferation but defects in differentiation of chondrocytes and osteoblasts. HB-EGF promoted BMSC proliferation via the Akt1 and Erk pathways but inhibited BMSC differentiation via restraining Smad1/5/8 activation. However, Dermo1-HB-EGF mice showed normal osteoclastogenesis and bone resorption. These results reveal an important function of autocrine or paracrine HB-EGF in mesenchymal stromal cell proliferation and differentiation and suggest that EGF signaling needs to be tightly controlled to maintain bone and articular cartilage integrity. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.

The bone size and quality, acquired during adolescent growth under the influence of anabolic hormones, growth factors, and nutrients, determine the height and bone stability and forecast osteoporosis risks in late life. Yet bone size and quality control mechanisms remain enigmatic. To study the roles of mammalian target of rapamycin (mTOR) signaling, sensor of growth factors and nutrients, in bone size and quality regulation, we ablated Tsc1, a suppressor of mTOR, in mesenchymal stromal cells (MSCs), monocytes, or their progenies osteoblasts and osteoclasts. mTOR activation in MSCs, but much less in osteoblasts, increased bone width and mass due to MSC hyperproliferation, but decreased bone length and mineral contents due to defective MSC differentiation. mTOR activation promotes bone mineral accretion by inhibiting osteoclast differentiation and activity directly or via coupling with MSCs. Tuberous sclerosis complex patient studies confirmed these findings. Thus, mTOR regulates bone size via MSCs and bone quality by suppressing catabolic activities of osteoclasts.

The gastrointestinal tract is responsible for food digestion and absorption. The muscularis propria propels the foodstuff through the GI tract and defects in intestine motility may cause obstruction disorders. Our present genetic studies identified non-receptor tyrosine kinase c-Abl as an important regulator of the muscularis propria homeostasis and a risk factor for rectal prolapse. Mouse deficient for c - Abl showed defects in the muscularis propria of gastrointestinal tract and older c - Abl −/− mice developed megaesophagus and rectal prolapse. Inhibition of c-Abl with imatinib mesylate, an anti-CML drug, or ablation of c-Abl using Prx1-Cre, which marks smooth muscle cells, recapitulated most of the muscularis propria phenotypes. The pathogenesis of rectal prolapse was attributable to overproliferation of smooth muscle cells, which was caused by enhanced ERK1/2 activation. Administration of ERK inhibitor U0126 impeded the development of rectal prolapse in c-Abl deficient mice. These results reveal a role for c-Abl-regulated smooth muscle proliferation in the pathogenesis of rectal prolapse, and imply that long-term use of imatinib mesylate may cause gastrointestinal problems in patients while ERK inhibitor may be effective in treating rectal prolapse.

Bone mass is determined by the balance between bone formation, carried out by mesenchymal stem cell-derived osteoblasts, and bone resorption, carried out by monocyte-derived osteoclasts. Here we investigated the potential roles of p38 MAPKs, which are activated by growth factors and cytokines including RANKL and BMPs, in osteoclastogenesis and bone resorption by ablating p38α MAPK in LysM+monocytes. p38α deficiency promoted monocyte proliferation but regulated monocyte osteoclastic differentiation in a cell-density dependent manner, with proliferating p38α−/− cultures showing increased differentiation. While young mutant mice showed minor increase in bone mass, 6-month-old mutant mice developed osteoporosis, associated with an increase in osteoclastogenesis and bone resorption and an increase in the pool of monocytes. Moreover, monocyte-specific p38α ablation resulted in a decrease in bone formation and the number of bone marrow mesenchymal stem/stromal cells, likely due to decreased expression of PDGF-AA and BMP2. The expression of PDGF-AA and BMP2 was positively regulated by the p38 MAPK-Creb axis in osteoclasts, with the promoters of PDGF-AA and BMP2 having Creb binding sites. These findings uncovered the molecular mechanisms by which p38α MAPK regulates osteoclastogenesis and coordinates osteoclastogenesis and osteoblastogenesis.

e15625 Background: Aiming at starting the ball rolling and contributing humble effort to promote Chinese traditional medicine, we performed a Chinese medicine based study of Warm and Removing decoction in combination with conventional therapy of hepatic cell carcinoma (HCC). Methods: Select 42 hospitalized patients with histologically confirmed HCC from Jan 2012 to Dec 2014 randomly, including 22 cases in the control group for conventional therapy of surgical resection and/or chemoradiotherapy as usual; and 20 patients in the study group for combined treatment of “warm and removing” decoction (WRD) on the basis of standard care. In the meantime, evaluation of clinical characteristics and quality of life was assessed. Results: There was a significant difference (P < 0.05) in AFP(alpha feto protein)/ALT(alanine transaminase) indices between groups of control and WRD. The DCR（disease control rate） was 43% in the WRD group compared with 34% in the control group. PFS(Progression-Free-Survival) and TTP(Time-to-Progression) of three-month duration were 60%,35% for WRD patients and 45%,40% for control patients, respectively. Our retrospective clinical study showed no overall survival (OS) benefit for HCC patients treated with WRD combination treatment compared with conventional care, while the QOL(quality of life) evaluation seemed to predict survival better for WRD patients than those for control patients. Conclusions: It had been shown that WRD played an important role in the combination therapy of primary liver cancer, which suggested distinguished liver cancer progression and heterogeneity with individual therapy response. Chinese medicine based combination therapy might be an additional choice with its better benefits and tolerability in the treatment of HCC.

This retrospective study aimed at evaluating the long-term outcomes and prognostic factors of microwave ablation (MWA) as a first-line treatment for hepatocellular carcinoma (HCC). 221 consecutive patients receiving MWA in our center between October 11, 2010 and December 31, 2013 were enrolled. Technique effectiveness was evaluated one month post-ablation. Initial complete ablation (CA1 st ) was gained in 201 (90.95%) patients, secondary CA (CA2 nd ) in 8 (3.62%) patients and the remaining 12 (5.43%) patients suffered from incomplete ablation (IA2 nd ) after two sessions of MWA. Patients with tumor size >5 cm were less likely to gain CA1 st . Procedure-related complications were recorded and no procedure-related death occurred. 22 (10.4%) complications occurred with 8 (3.8%) being major ones. Tumor characteristics (size, number, location) do not significantly influence complication rates. After a median follow-up of 41.0 (ranging 25.0–63.5) months, the median RFS and OS was 14.0 months (95% CI: 9.254–18.746) and 41.0 months (95% CI: 33.741–48.259) respectively. Multivariate analysis identified two significant prognosticators (levels of alpha fetal protein [AFP] and gamma-glutamyl transpeptidase [GGT]) of RFS and five significant prognosticators (tumor number, tumor size, AFP, GGT and recurrence type) of OS. In conclusion, MWA provides high technique effectiveness rate and is well tolerated in patients with HCC as a first-line treatment.

Bone marrow-derived mesenchymal stromal cells (BM-MSCs) are capable of differentiating into osteoblasts, chondrocytes, and adipocytes. Skewed differentiation of BM-MSCs contributes to the pathogenesis of osteoporosis. Yet how BM-MSC lineage commitment is regulated remains unclear. We show that ablation of p38α in Prx1+ BM-MSCs produced osteoporotic phenotypes, growth plate defects, and increased bone marrow fat, secondary to biased BM-MSC differentiation from osteoblast/chondrocyte to adipocyte and increased osteoclastogenesis and bone resorption. p38α regulates BM-MSC osteogenic commitment through TAK1-NF-κB signaling and osteoclastogenesis through osteoprotegerin (OPG) production by BM-MSCs. Estrogen activates p38α to maintain OPG expression in BM-MSCs to preserve the bone. Ablation of p38α in BM-MSCs positive for Dermo1, a later BM-MSC marker, only affected osteogenic differentiation. Thus, p38α mitogen-activated protein kinase (MAPK) in Prx1+ BM-MSCs acts to preserve the bone by promoting osteogenic lineage commitment and sustaining OPG production. This study thus unravels previously unidentified roles for p38α MAPK in skeletal development and bone remodeling.

Tak1 is a MAPKKK that can be activated by growth factors and cytokines such as RANKL and BMPs and its downstream pathways include NF-κB and JNK/p38 MAPKs. Tak1 is essential for mouse embryonic development and plays critical roles in tissue homeostasis. Previous studies have shown that Tak1 is a positive regulator of osteoclast maturation, yet its roles in bone growth and remodeling have not been assessed, as mature osteoclast-specific Tak1 deletion with Cstk-Cre resulted in runtedness and postnatal lethality. Here we generated osteoclast progenitor (monocyte)-specific Tak1 knockout mice and found that these mice show normal body weight, limb size and fertility and osteopetrosis with severity similar to that of RANK or RANKL deficient mice. Mechanistically, Tak1 deficiency altered the signaling of NF-κB, p38MAPK and Smad1/5/8 and the expression of PU.1, MITF, c-Fos and NFATc1, suggesting that Tak1 regulates osteoclast differentiation at multiple stages via multiple signaling pathways. Moreover, the Tak1 mutant mice showed defects in skull, articular cartilage and mesenchymal stromal cells. Ex vivo Tak1−/− monocytes also showed enhanced ability in promoting osteogenic differentiation of mesenchymal stromal cells. These findings indicate that Tak1 functions in osteoclastogenesis in a cell-autonomous manner and in osteoblastogenesis and chondrogenesis in non-cell-autonomous manners.