Systematic Review and Critical Appraisal of Prediction Models for Readmission in Coronary Artery Disease Patients: Assessing Current Efficacy and Future Directions.

Purpose: Coronary artery disease (CAD) patients frequently face readmissions due to suboptimal disease management. Prediction models are pivotal for detecting early unplanned readmissions. This review offers a unified assessment, aiming to lay the groundwork for enhancing prediction models and informing prevention strategies. Methods: A search through five databases (PubMed, Web of Science, EBSCOhost, Embase, China National Knowledge Infrastructure) up to September 2023 identified studies on prediction models for coronary artery disease patient readmissions for this review. Two independent reviewers used the CHARMS checklist for data extraction and the PROBAST tool for bias assessment. Results: From 12,457 records, 15 studies were selected, contributing 30 models targeting various CAD patient groups (AMI, CABG, ACS) from primarily China, the USA, and Canada. Models utilized varied methods such as logistic regression and machine learning, with performance predominantly measured by the c-index. Key predictors included age, gender, and hospital stay duration. Readmission rates in the studies varied from 4.8% to 45.1%. Despite high bias risk across models, several showed notable accuracy and calibration. Conclusion: The study highlights the need for thorough external validation and the use of the PROBAST tool to reduce bias in models predicting readmission for CAD patients.

Loss of the adaptor protein Sh3bgrl initiates ovarian fibrosis in zebrafish.

Ovarian fibrosis is a reproduction obstacle leading to female infertility in vertebrates, but the cause underlying the cellular events is unclear. Here, we found that the small adaptor protein SH3-domain-binding glutamate-rich protein like (Sh3bgrl) plays an important role in female reproduction in zebrafish. Two sh3bgrl mutant alleles that result in sh3bgrl depletion contribute to female spawning inability. Comparative transcriptome analysis revealed that sh3bgrl knockout mechanistically causes the upregulation of genes associated with extracellular matrix (ECM) and fiber generation in the zebrafish ovary. Consequently, extra ECM or fibers accumulate and are deposited in the ovary, resulting in eventual spawning inability. Our findings thus provide insights into understanding the underlying mechanism of infertility by ovarian fibrosis and provide a novel and valuable model to study female reproduction abnormality.

Erk5 functions in modulation of zebrafish intestinal permeability.

The intestine of zebrafish consists of mucosa, muscularis and serosa. Intestinal epithelial cells (IECs) act as a physical and biochemical barrier to protect against invasion by external commensal bacteria. Cell junction is one of the crucial basis of the barrier function. When cell junctions were disrupted, intestinal permeability would be naturally impeded. Extracellular signal-regulated kinase 5 (ERK5), belonging to the Mitogen-activated protein kinase (MAPK) family, is involved in the normal physiological development of the cardiovascular system and nervous system. But the role of erk5 in intestinal morphogenesis and intestinal function is yet to know. Here, we showed that knockout of the erk5 in zebrafish larvae resulted in intestinal wall hypoplasia, including the thinned intestinal wall, reduced intestinal folds, and disrupted cell junctions. In addition, the intestinal permeability assay demonstrated that knockout of erk5 resulted in increased intestinal permeability. All of these showed that erk5 plays an essential role in the maintenance of intestinal barrier function. Thus, our data indicate that erk5 is a critical effector in intestinal morphogenesis and intestinal function, and dysfunction of erk5 would lead to intestinal diseases.

SH3BGRL Suppresses Liver Tumor Progression through Enhanced ATG5-Dependent Autophagy.

SH3BGRL, an adaptor protein, is upregulated in breast cancers and indicates its tumorigenic role. But the function of SH3BGRL in other types of cancers is largely unknown. Here, we modulate SH3BGRL expression level in two liver cancer cells and conduct both in vitro and in vivo analyses of SH3BGRL in cell proliferation and tumorigenesis. Results demonstrate that SH3BGRL notably inhibits cell proliferation and arrests the cell cycle in both LO2 and HepG2 cells. Molecularly, SH3BGRL upregulates the expression of ATG5 from proteasome degradation as well as the inhibitions of Src activation and its downstream ERK and AKT signaling pathways, which eventually enhance autophagic cell death. The xenograft mouse model reveals that SH3BGRL overexpression can efficiently suppress tumorigenesis in vivo, while the additional silencing ATG5 in SH3BGRL-overexpressing cells attenuates the inhibitory effect of SH3BGRL on both hepatic tumor cell proliferation and tumorigenicity in vivo. The relevance of SH3BGRL downregulation in liver cancers and their progression is validated based on the large-scale tumor data. Taken together, our results clarify the suppressive role of SH3BGRL in tumorigenesis of liver cancer, which would be of help to the diagnosis of liver cancer, while either promoting the autophagy of liver cancer cells or inhibiting the downstream signaling induced from SH3BGRL downregulation would be a promising therapy.

Stacking polymer microspheres matrix: a facile, practical, and energy-saving strategy for suppression of acid mist.

The electroplating, electrolysis, and pickling industrial processes would generate numerous gas pollutes, acid mist, which could not be essentially diminished due to its synthesis mechanism and cause gaseous environmental pollution, equipment corrosion, and endanger workers' health. In this study, a facile, practical, and energy-saving acid mist suppression system was constructed by introducing a stacking microsphere matrix as a floating porous phase on the acid solution and not causing secondary pollution. The mechanism of this green acid mist suppression strategy mainly focused on size-selective blocking of acid mist droplets by dense stacking microsphere layer and dissipation of floating kinetic energy of bubbles in the acid mist. The factors relating to the matrix's microstructure, the particle size of microspheres, the combination of the complex particles with a wide range of particle sizes, and the thickness of the matrix on the acid mist suppression were explored. It found that the matrix constituted of a medium-sized polymer sphere (1.075 ± 0.175 mm) presents a better appearance in the acid mist suppression. When the thickness of this matrix reached 15 mm, its acid mist efficiency also came up to 100%, totally blocking the acid mist. Meanwhile, complex particles with different particle sizes and PMMA porous blocks are beneficial for suppressing acid mist. Herein, this research opened up a green and effective strategy for regulating this hazardous gas pollute, acid mist.

Nurse-led Telehealth Intervention for Rehabilitation (Telerehabilitation) Among Community-Dwelling Patients With Chronic Diseases: Systematic Review and Meta-analysis.

BACKGROUND: Chronic diseases are putting huge pressure on health care systems. Nurses are widely recognized as one of the competent health care providers who offer comprehensive care to patients during rehabilitation after hospitalization. In recent years, telerehabilitation has opened a new pathway for nurses to manage chronic diseases at a distance; however, it remains unclear which chronic disease patients benefit the most from this innovative delivery mode. OBJECTIVE: This study aims to summarize current components of community-based, nurse-led telerehabilitation programs using the chronic care model; evaluate the effectiveness of nurse-led telerehabilitation programs compared with traditional face-to-face rehabilitation programs; and compare the effects of telerehabilitation on patients with different chronic diseases. METHODS: A systematic review and meta-analysis were performed using 6 databases for articles published from 2015 to 2021. Studies comparing the effectiveness of telehealth rehabilitation with face-to-face rehabilitation for people with hypertension, cardiac diseases, chronic respiratory diseases, diabetes, cancer, or stroke were included. Quality of life was the primary outcome. Secondary outcomes included physical indicators, self-care, psychological impacts, and health-resource use. The revised Cochrane risk of bias tool for randomized trials was employed to assess the methodological quality of the included studies. A meta-analysis was conducted using a random-effects model and illustrated with forest plots. RESULTS: A total of 26 studies were included in the meta-analysis. Telephone follow-ups were the most commonly used telerehabilitation delivery approach. Chronic care model components, such as nurses-patient communication, self-management support, and regular follow-up, were involved in all telerehabilitation programs. Compared with traditional face-to-face rehabilitation groups, statistically significant improvements in quality of life (cardiac diseases: standard mean difference [SMD] 0.45; 95% CI 0.09 to 0.81; P=.01; heterogeneity: X21=1.9; I2=48%; P=.16; chronic respiratory diseases: SMD 0.18; 95% CI 0.05 to 0.31; P=.007; heterogeneity: X22=1.7; I2=0%; P=.43) and self-care (cardiac diseases: MD 5.49; 95% CI 2.95 to 8.03; P<.001; heterogeneity: X25=6.5; I2=23%; P=.26; diabetes: SMD 1.20; 95% CI 0.55 to 1.84; P<.001; heterogeneity: X24=46.3; I2=91%; P<.001) were observed in the groups that used telerehabilitation. For patients with any of the 6 targeted chronic diseases, those with hypertension and diabetes experienced significant improvements in their blood pressure (systolic blood pressure: MD 10.48; 95% CI 2.68 to 18.28; P=.008; heterogeneity: X21=2.2; I2=54%; P=0.14; diastolic blood pressure: MD 1.52; 95% CI -10.08 to 13.11, P=.80; heterogeneity: X21=11.5; I2=91%; P<.001), and hemoglobin A1c (MD 0.19; 95% CI -0.19 to 0.57 P=.32; heterogeneity: X24=12.4; I2=68%; P=.01) levels. Despite these positive findings, telerehabilitation was found to have no statistically significant effect on improving patients' anxiety level, depression level, or hospital admission rate. CONCLUSIONS: This review showed that telerehabilitation programs could be beneficial to patients with chronic disease in the community. However, better designed nurse-led telerehabilitation programs are needed, such as those involving the transfer of nurse-patient clinical data. The heterogeneity between studies was moderate to high. Future research could integrate the chronic care model with telerehabilitation to maximize its benefits for community-dwelling patients with chronic diseases. TRIAL REGISTRATION: International Prospective Register of Systematic Reviews CRD42022324676; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=324676.

Adaptor SH3BGRL drives autophagy-mediated chemoresistance through promoting PIK3C3 translation and ATG12 stability in breast cancers.

Acquired chemotherapy resistance is one of the main culprits in the relapse of breast cancer. But the underlying mechanism of chemotherapy resistance remains elusive. Here, we demonstrate that a small adaptor protein, SH3BGRL, is not only elevated in the majority of breast cancer patients but also has relevance with the relapse and poor prognosis of breast cancer patients. Functionally, SH3BGRL upregulation enhances the chemoresistance of breast cancer cells to the first-line doxorubicin treatment through macroautophagic/autophagic protection. Mechanistically, SH3BGRL can unexpectedly bind to ribosomal subunits to enhance PIK3C3 translation efficiency and sustain ATG12 stability. Therefore, inhibition of autophagy or silence of PIK3C3 or ATG12 can effectively block the driving effect of SH3BGRL on doxorubicin resistance of breast cancer cells in vitro and in vivo. We also validate that SH3BGRL expression is positively correlated with that of PIK3C3 or ATG12, as well as the constitutive occurrence of autophagy in clinical breast cancer tissues. Taken together, our data reveal that SH3BGRL upregulation would be a key driver to the acquired chemotherapy resistance through autophagy enhancement in breast cancer while targeting SH3BGRL could be a potential therapeutic strategy against breast cancer.Abbreviations: ABCs: ATP-binding cassette transporters; Act D: actinomycin D; ACTB/ß-actin: actin beta; ATG: autophagy-related; Baf A1: bafilomycin A1; CASP3: caspase 3; CHX: cycloheximide; CQ: chloroquine; Dox: doxorubicin; FBS: fetal bovine serum; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GEO: gene expression omnibus; GFP: green fluorescent protein; G6PD: glucose-6-phosphate dehydrogenase; GSEA: gene set enrichment analysis; IHC: immunochemistry; KEGG: Kyoto Encyclopedia of Genes and Genomes; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; 3-MA: 3-methyladenine; mRNA: messenger RNA; PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3; SH3BGRL: SH3 domain binding glutamate-rich protein-like; SQSTM1/p62: sequestosome 1; ULK1: unc-51 like autophagy activating kinase 1.

METTL1-m7 G-EGFR/EFEMP1 axis promotes the bladder cancer development.

BACKGROUND: The posttranscriptional modifications of transfer RNA (tRNA) are critical for all aspects of the tRNA function and have been implicated in the tumourigenesis and progression of many human cancers. By contrast, the biological functions of methyltransferase-like 1 (METTL1)-regulated m7 G tRNA modification in bladder cancer (BC) remain obscure. RESULTS: In this research, we show that METTL1 was highly expressed in BC, and its level was correlated with poor patient prognosis. Silencing METTL1 suppresses the proliferation, migration and invasion of BC cells in vitro and in vivo. Multi-omics analysis reveals that METTL1-mediated m7 G tRNA modification altered expression of certain target genes, including EGFR/EFEMP1. Mechanistically, METTL1 regulates the translation of EGFR/EFEMP1 via modifying certain tRNAs. Furthermore, forced expression of EGFR/EFEMP1 partially rescues the effect of METTL1 deletion on BC cells. CONCLUSIONS: Our findings demonstrate the oncogenic role of METTL1 and the pathological significance of the METTL1-m7 G-EGFR/EFEMP1 axis in the BC development, thus providing potential therapeutic targets for the BC treatment.

Adaptor SH3BGRL promotes breast cancer metastasis through PFN1 degradation by translational STUB1 upregulation.

Metastatic recurrence is still a major challenge in breast cancer treatment, but the underlying mechanisms remain unclear. Here, we report that a small adaptor protein, SH3BGRL, is upregulated in the majority of breast cancer patients, especially elevated in those with metastatic relapse, indicating it as a marker for the poor prognosis of breast cancer. Physiologically, SH3BGRL can multifunctionally promote breast cancer cell tumorigenicity, migration, invasiveness, and efficient lung colonization in nude mice. Mechanistically, SH3BGRL downregulates the acting-binding protein profilin 1 (PFN1) by accelerating the translation of the PFN1 E3 ligase, STUB1 via SH3BGRL interaction with ribosomal proteins, or/and enhancing the interaction of PFN1 with STUB1 to accelerate PFN1 degradation. Loss of PFN1 consequently contributes to downstream multiple activations of AKT, NF-kB, and WNT signaling pathways. In contrast, the forced expression of compensatory PFN1 in SH3BGRL-high cells efficiently neutralizes SH3BGRL-induced metastasis and tumorigenesis with PTEN upregulation and PI3K-AKT signaling inactivation. Clinical analysis validates that SH3BGRL expression is negatively correlated with PFN1 and PTEN levels, but positively to the activations of AKT, NF-kB, and WNT signaling pathways in breast patient tissues. Our results thus suggest that SH3BGRL is a valuable prognostic factor and a potential therapeutic target for preventing breast cancer progression and metastasis.

Delivery room resuscitation and short-term outcomes of extremely preterm and extremely low birth weight infants: a multicenter survey in North China.

BACKGROUND: Delivery room resuscitation assists preterm infants, especially extremely preterm infants (EPI) and extremely low birth weight infants (ELBWI), in breathing support, while it potentially exerts a negative impact on the lungs and outcomes of preterm infants. This study aimed to assess delivery room resuscitation and discharge outcomes of EPI and ELBWI in China. METHODS: The clinical data of EPI (gestational age [GA] <28 weeks) and ELBWI (birth weight [BW] <1000 g), admitted within 72 h of birth in 33 neonatal intensive care units from five provinces and cities in North China between 2017 and 2018, were analyzed. The primary outcomes were delivery room resuscitation and risk factors for delivery room intubation (DRI). The secondary outcomes were survival rates, incidence of bronchopulmonary dysplasia (BPD), and risk factors for BPD. RESULTS: A cohort of 952 preterm infants were enrolled. The incidence of DRI, chest compressions, and administration of epinephrine was 55.9% (532/952), 12.5% (119/952), and 7.0% (67/952), respectively. Multivariate analysis revealed that the risk factors for DRI were GA <28 weeks (odds ratio [OR], 3.147; 95% confidence interval [CI], 2.082-4.755), BW <1000 g (OR, 2.240; 95% CI, 1.606-3.125), and antepartum infection (OR, 1.429; 95% CI, 1.044-1.956). The survival rate was 65.9% (627/952) and was dependent on GA. The rate of BPD was 29.3% (181/627). Multivariate analysis showed that the risk factors for BPD were male (OR, 1.603; 95% CI, 1.061-2.424), DRI (OR, 2.094; 95% CI, 1.328-3.303), respiratory distress syndrome exposed to ≥2 doses of pulmonary surfactants (PS; OR, 2.700; 95% CI, 1.679-4.343), and mechanical ventilation ≥7 days (OR, 4.358; 95% CI, 2.777-6.837). However, a larger BW (OR, 0.998; 95% CI, 0.996-0.999), antenatal steroid (OR, 0.577; 95% CI, 0.379-0.880), and PS use in the delivery room (OR, 0.273; 95% CI, 0.160-0.467) were preventive factors for BPD (all P < 0.05). CONCLUSION: Improving delivery room resuscitation and management of respiratory complications are imperative during early management of the health of EPI and ELBWI.

Camel regulates development of the brain ventricular system.

Development of the brain ventricular system of vertebrates and the molecular mechanisms involved are not fully understood. The developmental genes expressed in the elements of the brain ventricular system such as the ependyma and circumventricular organs act as molecular determinants of cell adhesion critical for the formation of brain ventricular system. They control brain development and function, including the flow of cerebrospinal fluid. Here, we describe the novel distantly related member of the zebrafish L1-CAM family of genes-camel. Whereas its maternal transcripts distributed uniformly, the zygotic transcripts demonstrate clearly defined expression patterns, in particular in the axial structures: floor plate, hypochord, and roof plate. camel expresses in several other cell lineages with access to the brain ventricular system, including the midbrain roof plate, subcommissural organ, organum vasculosum lamina terminalis, median eminence, paraventricular organ, flexural organ, and inter-rhombomeric boundaries. This expression pattern suggests a role of Camel in neural development. Several isoforms of Camel generated by differential splicing of exons encoding the sixth fibronectin type III domain enhance cell adhesion differentially. The antisense oligomer morpholino-mediated loss-of-function of Camel affects cell adhesion and causes hydrocephalus and scoliosis manifested via the tail curled down phenotype. The subcommissural organ's derivative-the Reissner fiber-participates in the flow of cerebrospinal fluid. The Reissner fiber fails to form upon morpholino-mediated Camel loss-of-function. The Camel mRNA-mediated gain-of-function causes the Reissner fiber misdirection. This study revealed a link between Chl1a/Camel and Reissner fiber formation, and this supports the idea that CHL1 is one of the scoliosis factors.

Mutations of RNF213 are responsible for sporadic cerebral cavernous malformation and lead to a mulberry-like cluster in zebrafish.

Although familial forms of cerebral cavernous malformation are mainly attributed to three CCM genes (KRIT1, CCM2 and PDCD10), no mutation is identified in sporadic cerebral cavernous malformation cases with a unique lesion, indicating additional genes for sporadic cerebral cavernous malformation. To screen the candidate genes, we conducted whole exome sequencing in 31 sporadic cerebral cavernous malformation patients and 32 healthy controls, and identified 5 affected individuals carrying 6 heterozygous deleterious mutations in RNF213 but no RNF213 mutation in healthy individuals. To further confirm RNF213 was associated with cerebral cavernous malformation, we generated rnf213a homozygous knockout zebrafish and found mutation of rnf213a in zebrafish led to a mulberry-like cluster of disordered-flow vascular channels which was reminiscent of human cerebral cavernous malformation. In addition, we revealed kbtbd7 and anxa6 were significantly downregulated due to rnf213a mutation through transcriptomic sequencing and RT-qPCR analysis. Based on the mulberry-like phenotype partly rescued by mRNA of kbtbd7 as well as anxa6, we suggested that rnf213a promoted mulberry-like cluster via downregulation of kbtbd7 and anxa6. Altogether, we firstly demonstrate RNF213is a novel candidate gene for sporadic cerebral cavernous malformation and the mutation of rnf213a is responsible for the mulberry-like cluster in zebrafish.

Identification of STXBP6-IRF1 positive feedback loop in regulation of PD-L1 in cancer.

The clinical success of immune checkpoint blockade against diverse human cancers highlights the critical importance of insightful understanding into mechanisms underlying PD-L1 regulation. IFN-γ released by intratumoral lymphocytes regulates PD-L1 expression in tumor cells through JAK-STAT-IRF1 pathway, while the molecular events prime IRF1 to translocate into nucleus are still obscure. Here we identified STXBP6, previously recognized involving in SNARE complex assembly, negatively regulates PD-L1 transcription via retention of IRF1 in cytoplasm. IFN-γ exposure stimulates accumulation of cytosolic IRF1, which eventually saturates STXBP6 and triggers nuclear translocation of IRF1. Nuclear IRF1 in turn inhibits STXBP6 expression and thereby liberates more IRF1 to migrate to nucleus. Therefore, we identified a novel positive feedback loop between STXBP6 and IRF1 in regulation of PD-L1 expression in cancer. Furthermore, we demonstrate STXBP6 overexpression significantly inhibits T cell activation both in vitro and in vivo. These findings offer new insight into the complexity of PD-L1 expression in cancer and suggest a valuable measure to predict the response to PD-1/PD-L1-based immunotherapy.

Poly C Binding Protein 1 Regulates p62/SQSTM1 mRNA Stability and Autophagic Degradation to Repress Tumor Progression.

Accumulating evidence show that Poly C Binding Protein 1 (PCBP1) is deleted in distinct types of tumors as a novel tumor suppressor, but its tumor suppression mechanism remains elusive. Here, we firstly describe that downregulation of PCBP1 is significantly associated with clinical ovarian tumor progression. Mechanistically, PCBP1 overexpression affects various autophagy-related genes expression at various expression levels to attenuate the intrinsic cell autophagy, including the autophagy-initiating ULK, ATG12, ATG7 as well as the bona fide marker of autophagosome, LC3B. Accordingly, knockdown of the endogenous PCBP1 in turn enhances autophagy and less cell death. Meanwhile, PCBP1 upregulates p62/SQSTM1 via inhibition p62/SQSTM1 autophagolysome and proteasome degradation as well as its mRNA stability, consequently accompanying with the caspase 3 or 8 activation for tumor cell apoptosis. Importantly, clinical ovary cancer sample analysis consistently validates the relevance of PCBP1 expression to both p62/SQSTM1 and caspase-8 to overall survival, and indicates PCBP1 may be a master player to repress tumor initiation. Taken together, our results uncover the tumorigenic mechanism of PCBP1 depletion and suggest that inhibition of tumor cell autophagy with autophagic inhibitors could be an effective therapeutical strategy for PCBP1-deficient tumor.

Investigation of the awareness of and demand for hospice care and attitudes towards life-sustaining treatment at the end of life among community residents in Hangzhou.

BACKGROUND: To understand the status of residents' awareness of and demand for hospice care services in Hangzhou and to provide a reference for promoting the formulation of hospice care-related policies in China. METHODS: A small cross-sectional survey of 519 adults aged over 40 years old living in the rural-urban fringe and urban area of Xihu District, Hangzhou City, was conducted using convenience sampling and a self-designed questionnaire. The measures assessed awareness of hospice care (13-item scale), attitudes towards life support therapy (3-item scale), and demand for hospice care services (9-item scale). RESULTS: The rate of awareness of hospice care among community residents was 50.30%. A total of 51.0% of residents wanted only comfortable life-sustaining treatment at the end of their lives. The acceptance of hospice care was positively correlated with the degree of understanding (x2 = 18.382, P = 0.001), and residents in the urban area were more likely to prefer hospice care than residents in the urban-rural fringe (x2 = 7.186, P = 0.028). Elderly residents showed a stronger tendency to prefer comfortable life support therapy (x2 = 12.988, P < 0.001). A total of 83.04% of the residents accepted the current necessity for hospice care to be provided in medical institutions. The preferred locations were professional hospice care institutions or general hospitals. A total of 93.64% of the residents agreed that the number of beds in hospice care wards should not exceed 2. In addition, the residents could afford part of the out-of-pocket expenses for hospice care services, with the ability to pay under 200 yuan per day, and the improvement of facilities was expected. CONCLUSIONS: To improve public awareness and acceptance of hospice care and promote healthy development in China, it is necessary to promote hospice care education for everyone.

A novel taxane, difluorovinyl-ortataxel, effectively overcomes paclitaxel-resistance in breast cancer cells.

Paclitaxel (PTX) is widely used to treat breast and ovarian cancers, but innate and acquired resistance often compromises its applications. The objective of this study was to screen new-generation taxanes for their efficiency against both PTX-sensitive and PTX-resistant breast cancer cells. From twelve compounds, difluorovinyl-ortataxel (DFV-OTX) displayed potent cytotoxic activities against both PTX-sensitive and PTX-resistant breast cancer cells. Moreover, DFV-OTX effectively induced tubulin/microtubule polymerization and G2/M phase arrest, leading to apoptosis in both PTX-sensitive and PTX-resistant cancer cells. Molecular docking analysis showed that DFV-OTX possesses unique hydrogen-bonding and van der Waals interactions with ß-tubulin. LC-MS/MS analysis also demonstrated that the intracellular drug amount of DFV-OTX was lower than that of PTX, which would be critical to overcome PTX-resistance. Furthermore, DFV-OTX exhibited clear efficacy in the MCF-7R and MDA-MB-231R tumor xenografts in mouse models. Taken together, our results demonstrate that the novel taxane, DFV-OTX, can effectively overcome PTX-resistance in MDA-MB-231R cells, wherein the drug resistance was attributed to ABCB1/ABCG2 upregulation and a distinct mode of action in MCF-7R cells. Our results strongly indicate that DFV-OTX is a promising chemotherapeutic agent for the treatment of PTX-resistant cancers.

SH3BGRL confers innate drug resistance in breast cancer by stabilizing HER2 activation on cell membrane.

BACKGROUND: HER2-positive breast cancer is usually associated to the more aggressive progression and the worse prognosis, but the mechanism underlying the innate resistance to HER2-targeted therapy remains elusive. The scaffold protein SH3-domain-binding glutamic acid-rich protein-like protein (SH3BGRL) is indicated as a tumor suppressor in some cancers, but it is highly expressed in breast cancers. Here we characterized the tumorigenic function of SH3BGRL in HER2-expressing breast cancer cells and the subsequent effect in HER2-targeted therapies. METHODS: The interaction of SH3BGRL to HER2 were characterized with various truncated SH3BGRL mutants by immunoprecipitation and molecule docking simulation. The physiological roles of SH3BGRL interacting with HER2 in tumor progression and therapy implication were characterized by gain and loss of function approaches in vitro and in vivo. Immunohistochemistry was used for detections of SH3BGRL and p-HER2 (Y1196) expressions in xenografted tumors and human breast cancer tissues. Clinical relevance of SH3BGRL expression with HER2 was validated with both breast patient sample and the public data analyses. RESULTS: Our results demonstrated that SH3BGRL directly binds with HER2 on cell membrane via its motifs α1, α2 helixes and ß3 sheet, which postpones HER2 internalization upon EGF stimulation. Consequently, the association between SH3BGRL and HER2 contributed to the prolonged HER2 phosphorylation at specific tyrosine sites, especially at Y1196, and their downstream signaling activation. The relevance between SH3BGRL expression and p-HER2 (Y1196) phosphorylation was validated in both xenografted tumors and the breast cancer patient tissues. Mechanistically, SH3BGRL promoted breast tumor cell proliferation and survival, while reduced the cell sensitivity to anti-tumor drugs, especially to the HER2-targeted drugs. In contrast, Silencing SH3BGRL or inhibiting its downstream signals efficiently induced apoptosis of breast tumor cells with HER2 and SH3BGRL doubly positive expression. Database analysis also highlighted that SH3BGRL is a poor prognostic marker, especially for HER2-positive breast cancers. CONCLUSIONS: Our results disclose SH3BGRL as a novel posttranslational modulator of HER2 hyperactivation, which can lead to the intrinsic resistance to HER2-targeted therapy. SH3BGRL would be a pivotal therapy target and a diagnostic marker to HER2-positve patients. Thus, targeting SH3BGRL or the downstream signaling could relieve the innate resistance to some HER2-tageted therapies for both HER2 and SH3BGRL-postive breast cancers.