The expression of S100A8/S100A9 is inducible and regulated by the Hippo/YAP pathway in squamous cell carcinomas.

BACKGROUND: S100A8 and S100A9, two heterodimer-forming members of the S100 family, aberrantly express in a variety of cancer types. However, little is known about the mechanism that regulates S100A8/S100A9 co-expression in cancer cells. METHODS: The expression level of S100A8/S100A9 measured in three squamous cell carcinomas (SCC) cell lines and their corresponding xenografts, as well as in 257 SCC tissues. The correlation between S100A8/S100A9, Hippo pathway and F-actin cytoskeleton were evaluated using western blot, qPCR, ChIP and Immunofluorescence staining tests. IncuCyte ZOOM long time live cell image monitoring system, qPCR and Flow Cytometry measured the effects of S100A8/S100A9 and YAP on cell proliferation, cell differentiation and apoptosis. RESULTS: Here, we report that through activation of the Hippo pathway, suspension and dense culture significantly induce S100A8/S100A9 co-expression and co-localization in SCC cells. Furthermore, these expressional characteristics of S100A8/S100A9 also observed in the xenografts derived from the corresponding SCC cells. Importantly, Co-expression of S100A8/S100A9 detected in 257 SCC specimens derived from five types of SCC tissues. Activation of the Hippo pathway by overexpression of Lats1, knockdown of YAP, as well as disruption of F-actin indeed obviously results in S100A8/S100A9 co-expression in attached SCC cells. Conversely, inhibition of the Hippo pathway leads to S100A8/S100A9 co-expression in a manner opposite of cell suspension and dense. In addition, we found that TEAD1 is required for YAP-induced S100A8/S100A9-expressions. The functional studies provide evidence that knockdown of S100A8/S100A9 together significantly inhibit cell proliferation but promote squamous differentiation and apoptosis. CONCLUSIONS: Our findings demonstrate for the first time that the expression of S100A8/S100A9 is inducible by changes of cell shape and density through activation of the Hippo pathway in SCC cells. Induced S100A8/S100A9 promoted cell proliferation, inhibit cell differentiation and apoptosis.

Determining the optimal fasting glucose target for patients with type 2 diabetes: Results of the multicentre, open-label, randomized-controlled FPG GOAL trial.

The optimal fasting blood glucose (FBG) target of achieving HbA1c less than 7.0% in type 2 diabetes (T2D) patients remains controversial. This open-label trial randomized (1:3:3) 947 adults with uncontrolled T2D (HbA1c >7% to ≤10.5%) who were using one to three oral antidiabetic drugs to achieve an FBG target of 3.9 < FBG ≤5.6 mmol/L (Group 1), 3.9 < FBG ≤6.1 mmol/L (Group 2) or of 3.9 < FBG ≤7.0 mmol/L (Group 3). Targets were achieved using a pre-defined insulin glargine 100 U/mL titration scheme. The primary endpoint was proportion of patients achieving HbA1c <7.0% at 24 weeks. At 24 weeks, 44.4%, 46.1% and 37.7% of patients achieved HbA1c <7.0% in Groups 1, 2 and 3, respectively (P = 0.017; Group 2 vs Group 3). Alert hypoglycaemia (glucose ≤3.9 mmol/L) was significantly more frequent in Group 1 than in Group 3 (38.9 vs 23.3%; P < 0.001) but was not in Group 2 vs Group 3 (27.5% vs 23.3%; P = 0.177). Clinically important hypoglycaemia (glucose ≤3.0 mmol/L) was reported in 4.8%, 2.0% and 3.8% of patients in Groups 1, 2 and 3, respectively. In conclusion, the optimal FBG target for most Chinese patients with T2D appears to be 3.9-6.1 mmol/L.

Short-Term Outcomes of Open Reduction and Internal Fixation for Sanders Type III Calcaneal Fractures With and Without Bone Grafts.

Calcaneal fractures, often caused by a fall from a height, are the most common injuries encountered by orthopedic surgeons. Currently, open anatomic reduction and internal fixation (ORIF) is considered a valuable treatment of displaced intraarticular fractures of the calcaneus; however, the need for bone grafting in the treatment is still controversial. Therefore, in the present study, we investigated the outcomes of 2 methods (with and without bone grafting) used for the surgical treatment of Sanders type III calcaneal fractures. From January 2013 to September 2015, 57 cases (55 patients) with displaced Sanders type III calcaneal fractures (53 unilateral and 2 bilateral) were enrolled. The patients were divided into 2 groups: group I was treated by ORIF with bone grafting (n = 28) and group II was treated by ORIF without bone grafting (n = 29). The radiologic evaluation included Böhler's angle, Gissane's angle, and the height and width of the calcaneum. In addition, the American Orthopaedic Foot and Ankle Society questionnaires and visual analog scale were completed by the patients. During the follow-up period, no differences were found in the outcome measures (Böhler's angle, p = .447; Gissane's angle, p = .599; calcaneal height, p = .065; calcaneal width p = .077; and American Orthopaedic Foot and Ankle Society questionnaires, p = .282) with or without bone grafting. The only difference between the 2 groups was the occurrence of postoperative pain (p = .024 and p = ≤ .05), which was greater in the patients who had undergone bone grafting. We have provided evidence that bone grafting with internal fixation in the treatment of intraarticular calcaneal fractures failed to improve the restoration of Böhler's angle or Gissane's angle. No statistically significant difference was found in the short-term outcomes between the 2 methods used for the surgical treatment of Sanders type III calcaneal fractures.

Vernalophrys algivore gen. nov., sp. nov. (Rhizaria: Cercozoa: Vampyrellida), a New Algal Predator Isolated from Outdoor Mass Culture of Scenedesmus dimorphus.

Microbial contamination is the main cause of loss of biomass yield in microalgal cultures, especially under outdoor environmental conditions. Little is known about the identities of microbial contaminants in outdoor mass algal cultures. In this study, a new genus and species of vampyrellid amoeba, Vernalophrys algivore, is described from cultures of Scenedesmus dimorphus in open raceway ponds and outdoor flat-panel photobioreactors. This vampyrellid amoeba was a significant grazer of Scenedesmus and was frequently associated with a very rapid decline in algal numbers. We report on the morphology, subcellular structure, feeding behavior, molecular phylogeny, and life cycle. The new amoeba resembles Leptophrys in the shape of trophozoites and pseudopodia and in the mechanism of feeding (mainly by engulfment). It possesses two distinctive regions in helix E10_1 (nucleotides 117 to 119, CAA) and E23_1 (nucleotides 522 and 523, AG) of the 18S rRNA gene. It did not form a monophyletic group with Leptophrys in molecular phylogenetic trees. We establish a new genus, Vernalophrys, with the type species Vernalophrys algivore. The occurrence, impact of the amoeba on mass culture of S. dimorphus, and means to reduce vampyrellid amoeba contamination in Scenedesmus cultures are addressed. The information obtained from this study will be useful for developing an early warning system and control measures for preventing or treating this contaminant in microalgal mass cultures.

S100A7 acts as a dual regulator in promoting proliferation and suppressing squamous differentiation through GATA-3/caspase-14 pathway in A431 cells.

S100A7 is expressed in many squamous cell carcinomas (SCCs), such as SCC of the skin, and well-differentiated SCC always displays stronger staining of this protein. A431 cells, an epidermal cancer cell line, were selected as a cell model to investigate the roles and mechanism of S100A7 in SCC of the skin. In this study, we demonstrated that the overexpression of S100A7 in A431 cells significantly promoted cell proliferation in vitro and tumor growth in vivo, whereas it suppressed the expression of GATA-3, caspase-14 and three squamous differentiation markers, keratin-1, TG-1 and involucrin. Conversely, the overexpression of caspase-14 not only significantly decreased cell proliferation and delayed tumor growth but also markedly induced the expression of three squamous differentiation markers, whereas S100A7 and GATA-3 were not influenced. Further evidence showed that silencing GATA-3 greatly inhibited the expression of caspase-14 and three differentiation markers, while the expression of S100A7 was not changed; contrary results were obtained when overexpressing GATA-3. Importantly, restoring the expression of GATA-3 and caspase-14 in A431-S100A7 cells could bypass the ability of S100A7 to increase cell viability and repress squamous differentiation. These data suggested that S100A7 expression in SCC may play an important role in the maintenance of SCC cell dedifferentiation, at least in SCC of the skin.

[Corrigendum] Omi/HtrA2 pro-apoptotic marker differs in various hepatocellular carcinoma cell lines owing to ped/pea-15 expression level.

Subsequently to the publication of the above paper, an interested reader drew to the authors' attention that the control western blots shown for Fig. 1A and B on p. 908 and Fig. 8A and C on p. 911 were apparently the same, where different experiments were intended to have been portrayed. After having re­examined their original data files, the authors realized that these figures had been published with the control western blots shown incorrectly for Fig. 1A and 8C. The  corrected versions of this pair of figures are shown on the next page. Note that the corrections made to these figures do not affect the overall conclusions reported in the paper. The authors are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish this Corrigendum, and apologize to the readership for any inconvenience caused. [Oncology Reports 33: 905­912, 2015; DOI: 10.3892/or.2014.3656].

Integrated characterization of hepatobiliary tumor organoids provides a potential landscape of pharmacogenomic interactions.

Despite considerable efforts to identify human liver cancer genomic alterations that might unveil druggable targets, the systematic translation of multiomics data remains challenging. Here, we report success in long-term culture of 64 patient-derived hepatobiliary tumor organoids (PDHOs) from a Chinese population. A divergent response to 265 metabolism- and epigenetics-related chemicals and 36 anti-cancer drugs is observed. Integration of the whole genome, transcriptome, chromatin accessibility profiles, and drug sensitivity results of 64 clinically relevant drugs defines over 32,000 genome-drug interactions. RUNX1 promoter mutation is associated with an increase in chromatin accessibility and a concomitant gene expression increase, promoting a cluster of drugs preferentially sensitive in hepatobiliary tumors. These results not only provide an annotated PDHO biobank of human liver cancer but also suggest a systematic approach for obtaining a comprehensive understanding of the gene-regulatory network of liver cancer, advancing the applications of potential personalized medicine.

The expression and clinical significance of Omi/Htra2 in hepatocellular carcinoma.

BACKGROUND/AIMS: To investigate Omi/HtrA2 expression and its clinical significance in hepatocellular carcinoma. METHODOLOGY: We analyzed Omi/HtrA2 expression in hepatocellular carcinoma, paracancerous tissues and normal hepatic tissues by immunohistochemistry, RT-PCR and Western blot. Hypoxia-inducible factor-1α (HIF-1α) expression was also detected in hepatocellular carcinoma samples by immunohistochemistry. Meanwhile, we retrospectively analyzed the relationship between Omi/HtrA2 expression and the survival times of the patients. RESULTS: We found that Omi/HtrA2 overexpressed in hepatocellular carcinoma and was correlated with hepatocellular carcinoma differentiation, tumor size, portal vein invasion, clinical stage and lymph node metastasis. We also observed a significant inverse correlation between the expression of Omi,/HtrA2 and HIF-1α in hepatocellular carcinoma. The Kaplan-Meier estimates showed that patients who were Omi/HtrA2 positive had much longer survival times than those who were Omi/HtrA2 negative. Both univariate and multivariate analysis using the Cox regression model indicated that Omi/HtrA2 expression was a significant factor for prognosis. CONCLUSIONS: Hepatocellular carcinoma cells may need Omi/HtrA2 expression for apoptosis and Omi/HtrA2 might be an important prognostic marker for primary hepatocellular carcinoma.

Metabolic classification suggests the GLUT1/ALDOB/G6PD axis as a therapeutic target in chemotherapy-resistant pancreatic cancer.

Metabolic reprogramming is known as an emerging mechanism of chemotherapy resistance, but the metabolic signatures of pancreatic ductal adenocarcinomas (PDACs) remain unclear. Here, we characterize the metabolomic profile of PDAC organoids and classify them into glucomet-PDAC (high glucose metabolism levels) and lipomet-PDAC (high lipid metabolism levels). Glucomet-PDACs are more resistant to chemotherapy than lipomet-PDACs, and patients with glucomet-PDAC have a worse prognosis. Integrated analyses reveal that the GLUT1/aldolase B (ALDOB)/glucose-6-phosphate dehydrogenase (G6PD) axis induces chemotherapy resistance by remodeling glucose metabolism in glucomet-PDAC. Increased glycolytic flux, G6PD activity, and pyrimidine biosynthesis are identified in glucomet-PDAC with high GLUT1 and low ALDOB expression, and these phenotypes could be reversed by inhibiting GLUT1 expression or by increasing ALDOB expression. Pharmacological inhibition of GLUT1 or G6PD enhances the chemotherapy response of glucomet-PDAC. Our findings uncover potential metabolic heterogeneity related to differences in chemotherapy sensitivity in PDAC and develop a promising pharmacological strategy for patients with chemotherapy-resistant glucomet-PDAC through the combination of chemotherapy and GLUT1/ALDOB/G6PD axis inhibitors.

Hypoxia-inducible factor-1alpha suppressed hepatocellular carcinoma cell apoptosis through influencing on Omi/HtrA2 expression and its releasing from the mitochondrion.

Hypoxia-inducible factor-1alpha (HIF-1alpha) plays an important role in regulating hepatoma cell apoptosis. However, conclusions of different studies about the effects of HIF-1alpha expression on hepatoma cell apoptosis remain controversial. Omi/HtrA2 promotes cell apoptosis in some human cancer cells. Our previous experiments have demonstrated that primary hepatocellular carcinoma may need Omi/HtrA2 expression for cell apoptosis. Thus, we investigated the effect of HIF-1alpha on hepatocellular carcinoma cell apoptosis and Omi/ HtrA2 expression. In our study we found that HIF-1alpha gene could suppress hepatoma cell apoptosis, and Omi/HtrA2 mRNA and protein expression decreased with HIF-1alpha expression increase while Bcl-2 mRNA and protein expression increased with HIF-1alpha expression increase in HepG2 cells under normoxia condition. Meanwhile, Omi/HtrA2 protein expression increased with HIF-1alpha expression decrease in HepG2 cells under hypoxia culture. Taken together, these results demonstrated that HIF-1alpha suppressed hepatocellular carcinoma cell apoptosis through inhibiting Omi/HtrA2 expression and upregulating Bcl-2 expression to impede Omi/ HtrA2 releasing from the mitochondrion. The present finding further enriched and supported the role of HIF-1alpha expression on cell apoptosis of hepatoma cells.

MiR-29b-3p affects growth and biological functions of human extravillous trophoblast cells by regulating bradykinin B2 receptor.

Introduction: This study investigated miR-29b-3p's effects and mechanisms in preeclampsia development. Material and methods: In this study, we analysed the pathology and expression of miR-29b-3p and B2R mRNA from normal and preeclampsia placenta tissues using hematoxylin and eosin staining and RT-qPCR assay. For cell experiments, we used transwell assay CCK-8, flow cytometry and wound healing assay to determine the effects and correlation of miR-29b-3p and B2R in HTR-8/SVneo cell proliferation, apoptosis, cell cycle, cell invasion and migration in a preeclampsia cell model. Moreover, the mechanisms were determined using Western blot or immunofluorescence in different groups. Results: Clinical analysis revealed that miR-29b-3p gene expression dramatically increased with increasing degree of preeclampsia (p < 0.001 or p < 0.05, respectively). The HTR-8/SVneo cell biological activities of the model group were significantly depressed (p < 0.001). However, with miR-29b-3p inhibitor or B2R transfection, the HTR-8/SVneo cell biological activities significantly recovered (p < 0.001). Western blot assay showed that B2R, VEGF-A, CCND-1, MMP-2 and MMP-9 levels were suppressed in the model group, compared with those in the NC groups (p < 0.001, respectively). With miR-29b-3p inhibitor or B2R transfection, the protein expression levels of B2R, VEGF-A, CCND-1, MMP-2 and MMP-9 dramatically increased (p < 0.001, respectively). Conclusions: The down-regulation of miR-29b-3p could improve HTR-8/SVneo cell biological activities in a preeclampsia cell model by targeting B2R.

FOXA2 drives lineage plasticity and KIT pathway activation in neuroendocrine prostate cancer.

Prostate cancer adeno-to-neuroendocrine lineage transition has emerged as a mechanism of targeted therapeutic resistance. Identifying the direct molecular drivers and developing pharmacological strategies using clinical-grade inhibitors to overcome lineage transition-induced therapeutic resistance are imperative. Here, using single-cell multiomics analyses, we investigate the dynamics of cellular heterogeneity, transcriptome regulation, and microenvironmental factors in 107,201 cells from genetically engineered mouse prostate cancer samples with complete time series of tumor evolution seen in patients. We identify that FOXA2 orchestrates prostate cancer adeno-to-neuroendocrine lineage transition and that Foxa2 expression is significantly induced by androgen deprivation. Moreover, Foxa2 knockdown induces the reversal of adeno-to-neuroendocrine transition. The KIT pathway is directly regulated by FOXA2 and specifically activated in neuroendocrine prostate cancer (NEPC). Pharmacologic inhibition of KIT pathway significantly suppresses mouse and human NEPC tumor growth. These findings reveal that FOXA2 drives adeno-to-neuroendocrine lineage plasticity in prostate cancer and provides a potential pharmacological strategy for castration-resistant NEPC.

Influence of Fasting Plasma Glucose Targets on Glycemic Variability in Chinese Participants With Type 2 Diabetes: A Post Hoc Analysis of the FPG GOAL Trial (BEYOND III).

INTRODUCTION: This post hoc analysis examines the relationship between glycemic variability (GV) and fasting plasma glucose (FPG) targets used to achieve glycated hemoglobin (HbA1c) < 7%, and HbA1c levels after 24 weeks of treatment with insulin glargine and oral antidiabetic drugs (OADs) in Chinese participants with type 2 diabetes mellitus (T2DM) from the BEYOND III FPG GOAL trial (NCT02545842). METHODS: Participants were randomized for three FBG targets (≤ 5.6 mmol/L, ≤ 6.1 mmol/L, and ≤ 7.0 mmol/L) receiving insulin glargine 100 U/mL were analyzed for mean change from baseline to 24 weeks in postprandial glucose (PPG) excursion and FPG coefficient of variation (FPG-CV). The study analyzed change from baseline in HbA1c and the proportion of participants who achieved HbA1c < 7% at 24 weeks, according to their baseline FPG-CV and change from baseline in PPG excursion. RESULTS: The change in PPG excursion and FPG-CV from baseline to 24 weeks was not significantly different between the three groups stratified by randomization or by 24-week FPG levels. While the change in HbA1c from baseline to 24 weeks was slightly higher among participants with baseline FPG-CV < 33.3% (vs. > 66.7%; P = 0.023), a higher proportion of participants with baseline FPG-CV < 33.3% achieved HbA1c < 7% (P = 0.021). CONCLUSIONS: GV was not associated with either target FPG levels or HbA1c < 7.0% after 24 weeks of treatment with insulin glargine and OADs. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT02545842.

Integrated profiling of human pancreatic cancer organoids reveals chromatin accessibility features associated with drug sensitivity.

Chromatin accessibility plays an essential role in controlling cellular identity and the therapeutic response of human cancers. However, the chromatin accessibility landscape and gene regulatory network of pancreatic cancer are largely uncharacterized. Here, we integrate the chromatin accessibility profiles of 84 pancreatic cancer organoid lines with whole-genome sequencing data, transcriptomic sequencing data and the results of drug sensitivity analysis of 283 epigenetic-related chemicals and 5 chemotherapeutic drugs. We identify distinct transcription factors that distinguish molecular subtypes of pancreatic cancer, predict numerous chromatin accessibility peaks associated with gene regulatory networks, discover regulatory noncoding mutations with potential as cancer drivers, and reveal the chromatin accessibility signatures associated with drug sensitivity. These results not only provide the chromatin accessibility atlas of pancreatic cancer but also suggest a systematic approach to comprehensively understand the gene regulatory network of pancreatic cancer in order to advance diagnosis and potential personalized medicine applications.

Distinct mechanisms for TMPRSS2 expression explain organ-specific inhibition of SARS-CoV-2 infection by enzalutamide.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly become a global public health threat. The efficacy of several repurposed drugs has been evaluated in clinical trials. Among these drugs, a second-generation antiandrogen agent, enzalutamide, was proposed because it reduces the expression of transmembrane serine protease 2 (TMPRSS2), a key component mediating SARS-CoV-2-driven entry, in prostate cancer cells. However, definitive evidence for the therapeutic efficacy of enzalutamide in COVID-19 is lacking. Here, we evaluated the antiviral efficacy of enzalutamide in prostate cancer cells, lung cancer cells, human lung organoids and Ad-ACE2-transduced mice. Tmprss2 knockout significantly inhibited SARS-CoV-2 infection in vivo. Enzalutamide effectively inhibited SARS-CoV-2 infection in human prostate cells, however, such antiviral efficacy was lacking in human lung cells and organoids. Accordingly, enzalutamide showed no antiviral activity due to the AR-independent TMPRSS2 expression in mouse and human lung epithelial cells. Moreover, we observed distinct AR binding patterns between prostate cells and lung cells and a lack of direct binding of AR to TMPRSS2 regulatory locus in human lung cells. Thus, our findings do not support the postulated protective role of enzalutamide in treating COVID-19 through reducing TMPRSS2 expression in lung cells.

Epidemiological characteristics, medical costs and healthcare resource utilization of diabetes-related complications among Chinese patients with type 2 diabetes mellitus.

Objectives: To estimate the direct medical costs (DMCs) and healthcare resource utilization (HRU) of type 2 diabetes mellitus (T2DM)-related complications in China. Methods: Data from a total of 74,507 patients were extracted from the 2015 China Health Insurance Research Association Claims Database. The complications determined by primary diagnoses were categorized into three groups: 1) for mild acute and local chronic complications, both outpatients and inpatients were considered; 2) for severe acute complications, only inpatiens were considered; 3) for systemic chronic complications, a 1:1 propensity-score matching was performed to calculate the incremental DMCs and HRU of preexisting and new-onset patients. Results: Among the mild acute and local chronic complications, the DMCs and HRU per event were the highest for gangrene and laser treatment. Of the severe acute complications, the DMCs and HRU per event were highest for hyperosmotic nonketonic diabetic coma (HNDC), followed by severe hypoglycemia and ketosis. For systemic chronic complications, the DMCs and HRU associated with dialysis and myocardial infarction were the highest both in patients with new-onset complications and preexisting complications. Conclusions: The estimated economic data are required for policy decisions to optimize resource allocation and to evaluate different approaches for disease management.

Influence of Fasting Glucose Levels on Achieving Glycemic Target in Individuals with Type 2 Diabetes: a Post Hoc Analysis.

INTRODUCTION: FPG GOAL was a 24-week, open-label, treat-to-target randomized controlled trial which demonstrated that the optimal self-monitored fasting blood glucose (SM-FBG) target for most Chinese individuals with type 2 diabetes (T2D) using insulin glargine 100 IU/mL was 3.9-6.1 mmol/L. Individuals who achieved lower fasting plasma glucose (FPG) levels might achieve the target HbA1c of < 7% without increasing the risk of hypoglycemia. METHODS: For this post hoc analysis, individuals were redivided into three groups based on their actual laboratory FPG levels at 24 weeks: level 1, ≤ 5.6 mmol/L; level 2, > 5.6 to ≤ 6.1 mmol/L; and level 3, > 6.1 to ≤ 7.0 mmol/L. RESULTS: At week 24, 863 individuals with diabetes had available FPG data and 179, 122, and 179 individuals achieved FPG levels 1, 2, and 3, respectively. The proportion of individuals with HbA1c < 7% or HbA1c < 7% without hypoglycemia (≤ 3.9 or ≤ 3.0 mmol/L) was significantly higher in FPG levels 1 (p < 0.01) and 2 (p < 0.05) than in level 3. The least squares mean changes from baseline in HbA1c (- 1.77% and - 1.66% vs - 1.34%; both p < 0.001) and 2-h postprandial glucose (- 3.88 mmol/L and - 3.98 mmol/L vs - 3.22 mmol/L; both p < 0.05) were also significantly higher in FPG levels 1 and 2 compared with level 3. Linear regression analysis showed a moderate relationship between FPG and HbA1c levels at 24 weeks (r = 0.449). CONCLUSIONS: Chinese individuals with T2D who achieved lower FPG levels with insulin glargine 100 IU/mL were more likely to achieve the recommended target HbA1c of < 7% compared with those with higher FPG levels. ClinicalTrials.gov identifier NCT02545842.

Organoid technology for tissue engineering.

For centuries, attempts have been continuously made to artificially reconstitute counterparts of in vivo organs from their tissues or cells. Only in the recent decade has organoid technology as a whole technological field systematically emerged and been shown to play important roles in tissue engineering. Based on their self-organizing capacities, stem cells of versatile organs, both harvested and induced, can form 3D structures that are structurally and functionally similar to their in vivo counterparts. These organoid models provide a powerful platform for elucidating the development mechanisms, modeling diseases, and screening drug candidates. In this review, we will summarize the advances of this technology for generating various organoids of tissues from the three germ layers and discuss their drawbacks and prospects for tissue engineering.

Single-cell transcriptomics identifies a distinct luminal progenitor cell type in distal prostate invagination tips.

The identification of prostate stem/progenitor cells and characterization of the prostate epithelial cell lineage hierarchy are critical for understanding prostate cancer initiation. Here, we characterized 35,129 cells from mouse prostates, and identified a unique luminal cell type (termed type C luminal cell (Luminal-C)) marked by Tacstd2, Ck4 and Psca expression. Luminal-C cells located at the distal prostate invagination tips (termed Dist-Luminal-C) exhibited greater capacity for organoid formation in vitro and prostate epithelial duct regeneration in vivo. Lineage tracing of Luminal-C cells indicated that Dist-Luminal-C cells reconstituted distal prostate luminal lineages through self-renewal and differentiation. Deletion of Pten in Dist-Luminal-C cells resulted in prostatic intraepithelial neoplasia. We further characterized 11,374 human prostate cells and confirmed the existence of h-Luminal-C cells. Our study provides insights into the prostate lineage hierarchy, identifies Dist-Luminal-C cells as the luminal progenitor cell population in invagination tips and suggests one of the potential cellular origins of prostate cancer.

ERG orchestrates chromatin interactions to drive prostate cell fate reprogramming.

Although cancer is commonly perceived as a disease of dedifferentiation, the hallmark of early-stage prostate cancer is paradoxically the loss of more plastic basal cells and the abnormal proliferation of more differentiated secretory luminal cells. However, the mechanism of prostate cancer proluminal differentiation is largely unknown. Through integrating analysis of the transcription factors (TFs) from 806 human prostate cancers, we found that ERG was highly correlated with prostate cancer luminal subtyping. ERG overexpression in luminal epithelial cells inhibited those cells' normal plasticity to transdifferentiate into a basal lineage, and ERG superseded PTEN loss, which favored basal differentiation. ERG KO disrupted prostate cell luminal differentiation, whereas AR KO had no such effects. Trp63 is a known master regulator of the prostate basal lineage. Through analysis of 3D chromatin architecture, we found that ERG bound and inhibited the enhancer activity and chromatin looping of a Trp63 distal enhancer, thereby silencing its gene expression. Specific deletion of the distal ERG binding site resulted in the loss of ERG-mediated inhibition of basal differentiation. Thus, ERG, in its fundamental role in lineage differentiation in prostate cancer initiation, orchestrated chromatin interactions and regulated prostate cell lineage toward a proluminal program.