FGD5 in basal cells induces CXCL14 secretion that initiates a feedback loop to promote murine mammary epithelial growth and differentiation.

The interactions of environmental compartments with epithelial cells are essential for mammary gland development and homeostasis. Currently, the direct crosstalk between the endothelial niche and mammary epithelial cells remains poorly understood. Here, we show that faciogenital dysplasia 5 (FGD5) is enriched in mammary basal cells (BCs) and mediates critical interactions between basal and endothelial cells (ECs) in the mammary gland. Conditional deletion of Fgd5 reduced, whereas conditional knockin of Fgd5 increased, the engraftment and expansion of BCs, regulating ductal morphogenesis in the mammary gland. Mechanistically, murine mammary BC-expressed FGD5 inhibited the transcriptional activity of activating transcription factor 3 (ATF3), leading to subsequent transcriptional activation and secretion of CXCL14. Furthermore, activation of CXCL14/CXCR4/ERK signaling in primary murine mammary stromal ECs enhanced the expression of HIF-1α-regulated hedgehog ligands, which initiated a positive feedback loop to promote the function of BCs. Collectively, these findings identify functionally important interactions between BCs and the endothelial niche that occur through the FGD5/CXCL14/hedgehog axis.

Targeting IL-17A enhances imatinib efficacy in Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia.

Dysregulated hematopoietic niches remodeled by leukemia cells lead to imbalances in immunological mediators that support leukemogenesis and drug resistance. Targeting immune niches may ameliorate disease progression and tyrosine kinase inhibitor (TKI) resistance in Philadelphia chromosome-positive B-ALL (Ph+ B-ALL). Here, we show that T helper type 17 (Th17) cells and IL-17A expression are distinctively elevated in Ph+ B-ALL patients. IL-17A promotes the progression of Ph+ B-ALL. Mechanistically, IL-17A activates BCR-ABL, IL6/JAK/STAT3, and NF-kB signalling pathways in Ph+ B-ALL cells, resulting in robust cell proliferation and survival. In addition, IL-17A-activated Ph+ B-ALL cells secrete the chemokine CXCL16, which in turn promotes Th17 differentiation, attracts Th17 cells and forms a positive feedback loop supporting leukemia progression. These data demonstrate an involvement of Th17 cells in Ph+ B-ALL progression and suggest potential therapeutic options for Ph+ B-ALL with Th17-enriched niches.

Mesaconine alleviates doxorubicin-triggered cardiotoxicity and heart failure by activating PINK1-dependent cardiac mitophagy.

Aberrant mitophagy has been identified as a driver for energy metabolism disorder in most cardiac pathological processes. However, finding effective targeted agents and uncovering their precise modulatory mechanisms remain unconquered. Fuzi, the lateral roots of Aconitum carmichaelii, shows unique efficacy in reviving Yang for resuscitation, which has been widely used in clinics. As a main cardiotonic component of Fuzi, mesaconine has been proven effective in various cardiomyopathy models. Here, we aimed to define a previously unrevealed cardioprotective mechanism of mesaconine-mediated restoration of obstructive mitophagy. The functional implications of mesaconine were evaluated in doxorubicin (DOX)-induced heart failure models. DOX-treated mice showed characteristic cardiac dysfunction, ectopic myocardial energy disorder, and impaired mitophagy in cardiomyocytes, which could be remarkably reversed by mesaconine. The cardioprotective effect of mesaconine was primarily attributed to its ability to promote the restoration of mitophagy in cardiomyocytes, as evidenced by elevated expression of PINK1, a key mediator of mitophagy induction. Silencing PINK1 or deactivating mitophagy could completely abolish the protective effects of mesaconine. Together, our findings suggest that the cardioprotective effects of mesaconine appear to be dependent on the activation of PINK1-induced mitophagy and that mesaconine may constitute a promising therapeutic agent for the treatment of heart failure.

Spatial Distribution Characteristics of Suitable Planting Areas for Pyrus Species under Climate Change in China.

Planting suitability determines the distribution and yield of crops in a given region which can be greatly affected by climate change. In recent years, many studies have shown that carbon dioxide fertilization effects increase the productivity of temperate deciduous fruit trees under a changing climate, but the potential risks to fruit tree planting caused by a reduction in suitable planting areas are rarely reported. In this study, Maxent was first used to investigate the spatial distribution of five Pyrus species in China, and the consistency between the actual production area and the modeled climatically suitable area under the current climatic conditions were determined. In addition, based on Coupled Model Intercomparison Project Phase 6, three climate models were used to simulate the change in suitable area and the migration trend for different species under different emission scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5). The results showed that the suitable area for pear was highly consistent with the actual main production area under current climate conditions. The potential planting areas of P. ussuriensis showed a downward trend under all emission paths from 2020 to 2100; other species showed a trend of increasing first and then decreasing or slowing down and this growth effect was the most obvious in 2020-2040. Except for P. pashia, other species showed a migration trend toward a high latitude, and the trend was more prominent under the high emission path. Our results emphasize the response difference between species to climate change, and the method of consistency analysis between suitable planting area and actual production regions cannot only evaluate the potential planting risk but also provide a reasonable idea for the accuracy test of the modeled results. This work has certain guiding and reference significance for the protection of pear germplasm resources and the prediction of yield.

Monitoring and analysis of desertification surrounding Qinghai Lake (China) using remote sensing big data.

Desertification is one of the most serious ecological environmental problems in the world. Monitoring the spatiotemporal dynamics of desertification is crucial for its control. The region around Qinghai Lake, in the northeastern part of the Qinghai-Tibet Plateau in China, is a special ecological function area and a climate change sensitive area, making its environmental conditions a great concern. Using cloud computing via Google Earth Engine (GEE), we collected Landsat 5 TM, Landsat 8 OLI/TIRS, and MODIS Albedo images from 2000 to 2020 in the region around Qinghai Lake, acquired land surface albedo (Albedo), and normalized vegetation index (NDVI) to build a remote sensing monitoring model of desertification. Our results showed that the desertification difference index based on the Albedo-NDVI feature space could reflect the degree of desertification in the region around Qinghai Lake. GEE offers significant advantages, such as massive data processing and long-term dynamic monitoring. The desertification land area fluctuated downward in the study area from 2000 to 2020, and the overall desertification status improved. Natural factors, such as climate change from warm-dry to warm-wet and decreased wind speed, and human factors improved the desertification situation. The findings indicate that desertification in the region around Qinghai Lake has been effectively controlled, and the overall desertification trend is improving.

Insulin induces insulin receptor degradation in the liver through EphB4.

Insulin signaling is essential for glucose metabolism, and insulin decreases insulin receptor (InsR) levels in a dose-dependent and time-dependent manner. However, the regulatory mechanisms of InsR reduction upon insulin stimulation remain poorly understood. Here, we show that Eph receptor B4 (EphB4), a tyrosine kinase receptor that modulates cell adhesion and migration, can bind directly to InsR, and this interaction is markedly enhanced by insulin. Due to the adaptor protein 2 (Ap2) complex binding motif in EphB4, the interaction of EphB4 and InsR facilitates clathrin-mediated InsR endocytosis and degradation in lysosomes. Hepatic overexpression of EphB4 decreases InsR and increases hepatic and systemic insulin resistance in chow-fed mice, whereas genetic or pharmacological inhibition of EphB4 improve insulin resistance and glucose intolerance in obese mice. These observations elucidate a role for EphB4 in insulin signaling, suggesting that EphB4 might represent a therapeutic target for the treatment of insulin resistance and type 2 diabetes.

The cell cycle inhibitor P21 promotes the development of pulmonary fibrosis by suppressing lung alveolar regeneration.

The cell cycle inhibitor P21 has been implicated in cell senescence and plays an important role in the injury-repair process following lung injury. Pulmonary fibrosis (PF) is a fibrotic lung disorder characterized by cell senescence in lung alveolar epithelial cells. In this study, we report that P21 expression was increased in alveolar epithelial type 2 cells (AEC2s) in a time-dependent manner following multiple bleomycin-induced PF. Repeated injury of AEC2s resulted in telomere shortening and triggered P21-dependent cell senescence. AEC2s with elevated expression of P21 lost their self-renewal and differentiation abilities. In particular, elevated P21 not only induced cell cycle arrest in AEC2s but also bound to P300 and ß-catenin and inhibited AEC2 differentiation by disturbing the P300-ß-catenin interaction. Meanwhile, senescent AEC2s triggered myofibroblast activation by releasing profibrotic cytokines. Knockdown of P21 restored AEC2-mediated lung alveolar regeneration in mice with chronic PF. The results of our study reveal a mechanism of P21-mediated lung regeneration failure during PF development, which suggests a potential strategy for the treatment of fibrotic lung diseases.

TRIB3‒GSK-3ß interaction promotes lung fibrosis and serves as a potential therapeutic target.

Pulmonary fibrosis (PF) is a chronic, progressive, fatal interstitial lung disease with limited available therapeutic strategies. We recently reported that the protein kinase glycogen synthase kinase-3ß (GSK-3ß) interacts with and inactivates the ubiquitin-editing enzyme A20 to suppress the degradation of the transcription factor CCAAT/enhancer-binding protein beta (C/EBPß) in alveolar macrophages (AMs), resulting in a profibrotic phenotype of AMs and promoting the development of PF. Here, we showed that chronic lung injury upregulated the stress response protein tribbles homolog 3 (TRIB3), which interacted with GSK-3ß and stabilized GSK-3ß from ubiquitination and degradation. Elevated GSK-3ß expression phosphorylated A20 to inhibit its ubiquitin-editing activity, causing the accumulation of C/EBPß and the production of several profibrotic factors in AMs and promoting PF development. Activated C/EBPß, in turn, increased the transcription of TRIB3 and GSK-3ß, thereby establishing a positive feedback loop in AMs. The knockdown of TRIB3 expression or the pharmacologic disruption of the TRIB3‒GSK-3ß interaction was an effective PF treatment. Our study reveals an intact profibrotic axis of TRIB3‒GSK-3ß‒A20‒C/EBPß in AMs, which represents a target that may provide a promising treatment strategy for PF.

The chemokine CCL1 triggers an AMFR-SPRY1 pathway that promotes differentiation of lung fibroblasts into myofibroblasts and drives pulmonary fibrosis.

Recruitment of immune cells to the site of inflammation by the chemokine CCL1 is important in the pathology of inflammatory diseases. Here, we examined the role of CCL1 in pulmonary fibrosis (PF). Bronchoalveolar lavage fluid from PF mouse models contained high amounts of CCL1, as did lung biopsies from PF patients. Immunofluorescence analyses revealed that alveolar macrophages and CD4+ T cells were major producers of CCL1 and targeted deletion of Ccl1 in these cells blunted pathology. Deletion of the CCL1 receptor Ccr8 in fibroblasts limited migration, but not activation, in response to CCL1. Mass spectrometry analyses of CCL1 complexes identified AMFR as a CCL1 receptor, and deletion of Amfr impaired fibroblast activation. Mechanistically, CCL1 binding triggered ubiquitination of the ERK inhibitor Spry1 by AMFR, thus activating Ras-mediated profibrotic protein synthesis. Antibody blockade of CCL1 ameliorated PF pathology, supporting the therapeutic potential of targeting this pathway for treating fibroproliferative lung diseases.

Autophagic Flux Detection: Significance and Methods Involved.

Macroautophagy is an important biological process in eukaryotic cells by which longevity proteins, misfolded proteins, and damaged organelles are degraded. The autophagy process consists of three key steps: (1) the formation of autophagosomes; (2) the fusion of the autophagosomes with lysosomes; and (3) the degradation of the contents of autolysosomes. If any of the three steps is impaired, autophagy will not be able to complete its biological function. Dysfunctional or blocked autophagy is closely involved in the pathogenesis of a variety of diseases. The accurate determination of the autophagy activity in vivo and in vitro has become a challenge in the field of autophagy research. At present, the most widely used detection method to determine autophagy activity in mammalian cells is to quantify LC3B in the cells by Western blot, or to observe the formation and changes of autophagosomes and autolysosomes by immunofluorescence and electron microscopy. However, ignoring the dynamic characteristics of autophagy and only evaluating the number of autophagosomes or the presence of LC3B cannot completely reflect the activation or a blockage of the autophagy system, and objectively analyze its real role in the occurrence and development of a disease. For example, the accumulation of autophagosomes and autolysosomes can occur through an increase in substrate to be degraded after the activation of autophagy, or it may be caused by the partial obstruction or blockage of autophagy. In this chapter, new and familiar ways to detect the autophagic flux are methodically summarized to provide researchers with a multi-angled viewpoint.

Associations Between Diabetes and Idiopathic Pulmonary Fibrosis: a Study-level Pooled Analysis of 26 Million People.

CONTEXT: Diabetes mellitus (DM) is a systemic disease characterized by chronic hyperglycemia associated with inflammation and oxidative stress, and the lung may be a target organ of diabetic microvascular damage. Several studies have indicated a positive association between idiopathic pulmonary fibrosis (IPF) and diabetes with controversial findings. OBJECTIVE: Primary outcomes were to compare the prevalence of DM among individuals with IPF to non-IPF controls, and the prevalence of IPF among individuals with DM to non-DM controls. METHODS: Data sources include PubMed, EMBASE, and the Cochrane Library. Studies contained sufficient data to calculate the prevalence of DM among individuals with and without IPF, or the prevalence of IPF among individuals with and without DM. Two investigators independently identified eligible studies and extracted data. Pooled odds ratio (OR) with 95% CI was the summary effect measure. RESULTS: Eighteen studies including 26 410 623 individuals met the eligibility criteria, of whom 16 recruited people with IPF and 2 recruited people with DM. The OR of DM in IPF patients was 1.54 (95% CI, 1.30-1.84; P < .001) compared to that in non-IPF controls. However, compared with that in non-DM patients, the risk of IPF in DM patients was not found to be significantly reduced (OR: 0.89; 95% CI, 0.64-1.25; P = .497). CONCLUSION: This meta-analysis suggests that people with IPF have 1.54 times increased odds of diabetes compared to non-IPF controls, while whether patients with DM have an increased risk of IPF is still controversial. Further large, prospective cohort studies investigating the prevalence of IPF in diabetic patients are warranted.

Faciogenital Dysplasia 5 supports cancer stem cell traits in basal-like breast cancer by enhancing EGFR stability.

Most basal-like breast cancers (BLBCs) are triple-negative breast cancers (TNBCs), which have the worst prognosis and distant metastasis-free survival among breast cancer subtypes. Now, no targeted therapies are available for patients with BLBC due to the lack of reliable and effective molecular targets. Here, we performed the BLBC tissue microarray-based immunohistochemical analysis and showed that Faciogenital Dysplasia 5 (FGD5) abundance is associated with poor prognosis in BLBCs. FGD5 deletion decreased the proliferation, invasion, and tumorsphere formation capacity of BLBC cells. Furthermore, genetic inhibition of Fgd5 in mouse mammary epithelial cells attenuated BLBC initiation and progression by reducing the self-renewal ability of tumor-initiating cells. In addition, FGD5 abundance was positively correlated with the abundance of epidermal growth factor receptor (EGFR) in BLBCs. FGD5 ablation decreased EGFR abundance by reducing EGFR stability in TNBC cells in 2D and 3D culture conditions. Mechanistically, FGD5 binds to EGFR and interferes with basal EGFR ubiquitination and degradation induced by the E3 ligase ITCH. Impaired EGFR degradation caused BLBC cell proliferation and promoted invasive properties and self-renewal. To verify the role of the FGD5-EGFR interaction in the regulation of EGFR stability, we screened a cell-penetrating α-helical peptide PER3 binding with FGD5 to disrupt the interaction. Treatment of BLBC patient-derived xenograft-bearing mice with the peptide PER3 disrupting the FGD5-EGFR interaction either with or without chemotherapy reduced BLBC progression. Our study identified FGD5 as a positive modulator of tumor-initiating cells and suggests a potential therapeutic option for the BLBC subtype of breast cancer.

TRIB3 promotes MYC-associated lymphoma development through suppression of UBE3B-mediated MYC degradation.

The transcription factor MYC is deregulated in almost all human cancers, especially in aggressive lymphomas, through chromosomal translocation, amplification, and transcription hyperactivation. Here, we report that high expression of tribbles homologue 3 (TRIB3) positively correlates with elevated MYC expression in lymphoma specimens; TRIB3 deletion attenuates the initiation and progression of MYC-driven lymphoma by reducing MYC expression. Mechanistically, TRIB3 interacts with MYC to suppress E3 ubiquitin ligase UBE3B-mediated MYC ubiquitination and degradation, which enhances MYC transcriptional activity, causing high proliferation and self-renewal of lymphoma cells. Use of a peptide to disturb the TRIB3-MYC interaction together with doxorubicin reduces the tumor burden in MycEµ mice and patient-derived xenografts. The pathophysiological relevance of UBE3B, TRIB3 and MYC is further demonstrated in human lymphoma. Our study highlights a key mechanism for controlling MYC expression and a potential therapeutic option for treating lymphomas with high TRIB3-MYC expression.

PML-RARα interaction with TRIB3 impedes PPARγ/RXR function and triggers dyslipidemia in acute promyelocytic leukemia.

Although dyslipidemia commonly occurs in patients with acute promyelocytic leukemia (APL) in response to anti-APL therapy, the underlying mechanism and the lipid statuses of patients with newly diagnosed APL remain to be addressed. Methods: We conducted a retrospective study to investigate the lipid profiles of APL patients. PML-RARα transgenic mice and APL cells-transplanted mice were used to assess the effects of APL cells on the blood/liver lipid levels. Subsequently, gene set enrichment analysis, western blot and dual luciferase reporter assay were performed to examine the role and mechanism of PML-RARα and TRIB3 in lipid metabolism regulation in APL patients at pretreatment and after induction therapy. Results: APL patients exhibited a higher prevalence of dyslipidemia before anti-APL therapy based on a retrospective study. Furthermore, APL cells caused secretion of triglycerides, cholesterol, and PCSK9 from hepatocytes and degradation of low-density lipoprotein receptors in hepatocytes, which elevated the lipid levels in APL cell-transplanted mice and Pml-Rarα transgenic mice. Mechanistically, pseudokinase TRIB3 interacted with PML-RARα to inhibit PPARγ activity by interfering with the interaction of PPARγ and RXR and promoting PPARγ degradation. Thus, reduced PPARγ activity in APL cells decreased leptin but increased resistin expression, causing lipid metabolism disorder in hepatocytes and subsequent dyslipidemia in mice. Although arsenic/ATRA therapy degraded PML-RARα and restored PPARγ expression, it exacerbated dyslipidemia in APL patients. The elevated TRIB3 expression in response to arsenic/ATRA therapy suppressed PPARγ activity by disrupting the PPARγ/RXR dimer, which resulted in dyslipidemia in APL patients undergoing therapy. Indeed, the PPAR activator not only enhanced the anti-APL effects of arsenic/ATRA by suppressing TRIB3 expression but also reduced therapy-induced dyslipidemia in APL patients. Conclusion: Our work reveals the critical role of the PML-RARα/PPARγ/TRIB3 axis in the development of dyslipidemia in APL patients, potentially conferring a rationale for combining ATRA/arsenic with the PPAR activator for APL treatment.

G-Protein-Coupled Estrogen Receptor 1 Promotes Gender Disparities in Hepatocellular Carcinoma via Modulation of SIN1 and mTOR Complex 2 Activity.

Due to its intricate heterogeneity and limited treatment, hepatocellular carcinoma (HCC) has been considered a major cause of cancer-related mortality worldwide. Increasing evidence indicates that G-protein-coupled estrogen receptor 1 (GPER1) can promote estrogen-dependent hepatocellular proliferation by activating AKT signaling. The mTOR complex 2 (mTORC2), whose integrity and activity are modulated by its subunit Sin1, controls the activation of AKT by phosphorylation at position S473. In this study, we investigate the modulation of Sin1 and how estrogen signaling may influence the mTORC2-AKT cascade in HCC cells and a DEN-induced mouse model. We have found that estradiol-dependent Sin1 expression is transcriptionally modulated by GPER1 as well as ERα. GPER1 is able to regulate Sin1 stability via nuclear translocation, therefore increasing Sin1-mTORC2-AKT activation. Moreover, Sin1 interacts with ERα and further enhances its transcriptional activity. Sin1 is highly expressed in acute liver injury and in cases of HCC harboring high expression of GPER1 and constitutive activation of mTORC2-AKT signaling. GPER1 inhibition using the antagonist G-15 reverses DEN-induced acute liver injury by suppressing Sin1 expression and mTORC2-AKT activation. Notably, SIN1 expression varies between male and female mice in the context of both liver injury and liver cancer. In addition, high SIN1 expression is predictive of good prognosis in both male and female patients with HCC who are free from hepatitis virus infection and who report low alcohol consumption. Hence, here we demonstrate that Sin1 can be regulated by GPER1 both through nongenomic and indirect genomic signaling. IMPLICATIONS: This study suggests that Sin1 may be a novel HCC biomarker which is gender-dependent and sensitive to particular risk factor.

Chronic Obstructive Pulmonary Disease and Autophagy.

Chronic Obstructive Pulmonary Disease (COPD) is a classical chronic respiratory disease with the pathological changes involving the bronchi and alveoli. Many of the risk factors of COPD can induce autophagy in different kinds of cells in lung tissue including alveolar epithelial cells, broncho epithelial cells, and fibroblasts. Over-activation of autophagy may cause emphysema by inducing autophagic cell death. However, the bronchitis and fibrosis may be mainly caused by autophagic flux blocking. Thus, understanding the role of autophagy in the pathogenesis of COPD is important for the anti-COPD drug development.