Extracellular vesicles released by hypoxia-induced tumor-associated fibroblasts impart chemoresistance to breast cancer cells via long noncoding RNA H19 delivery

Recently, extracellular vesicles (EVs) have been emphasized in regulating the hypoxic tumor microenvironment of breast cancer (BC), where tumor-associated fibroblasts (TAFs) play a significant role. In this study, we describe possible molecular mechanisms behind the pro-tumoral effects of EVs, secreted by hypoxia (HP)-induced TAFs, on BC cell growth, metastasis, and chemoresistance. These mechanisms are based on long noncoding RNA H19 (H19) identified by microarray analysis. We employed an in silico approach to identify differentially expressed lncRNAs that were associated with BC. Subsequently, we explored possible downstream regulatory mechanisms. We isolated EVs from TAFs that were exposed to HP, and these EVs were denoted as HP-TAF-EVs henceforth. MTT, transwell, flow cytometry, and TUNEL assays were performed to assess the malignant phenotypes of BC cells. A paclitaxel (TAX)-resistant BC cell line was constructed, and xenograft tumor and lung metastasis models were established in nude mice for in vivo verification. Our observation revealed that lncRNA H19 was significantly overexpressed, whereas miR-497 was notably downregulated in BC. HP induced activation of TAFs and stimulated the secretion of EVs. Coculture of HP-TAF-EVs and BC cells led to an increase in TAX resistance of the latter. HP-TAF-EVs upregulated methylation of miR-497 by delivering lncRNA H19, which recruited DNMT1, thus lowering the expression of miR-497. In addition, lncRNA H19-containing HP-TAF-EVs hindered miR-497 expression, enhancing tumorigenesis and TAX resistance of BC cells in vivo. Our study presents evidence for the contribution of lncRNA H19-containing HP-TAF-EVs in the reduction of miR-497 expression through the recruitment of DNMT1, which in turn promotes the growth, metastasis, and chemoresistance of BC cells.

Association between a body shape index and prostate cancer: a cross-sectional study of NHANES 2001-2018

OBJECTIVE

Abdominal obesity, especially visceral fat, may have negative effects on the development and progression of prostate cancer (PCa). A body shape index (ABSI) can more accurately measure visceral fat accumulation. This study aimed to investigate the association between ABSI and PCa in US adults.

METHODS

11,013 participants were enrolled in the National Health and Nutrition Examination Survey from 2001 to 2018. Weighted multivariate logistic regression analyses were employed to explore the independent relationship between ABSI and PCa. Moreover, restricted cubic spline (RCS) analysis, subgroup analysis, and interaction tests were performed.

RESULTS

ABSI was positively associated with the presence of PCa. When comparing the second, third, and fourth ABSI quartile to the lowest quartile, the adjusted odds ratios (95% confidence intervals) for PCa risk were 1.34 (0.77, 2.31), 1.75 (1.03, 3.00), and 1.91 (1.12, 3.27), respectively (p for trend = 0.011). The restricted cubic spline regression analysis did not reveal a non-linear correlation between ABSI and PCa (p for non-linearity = 0.076). Subgroup analysis showed a significant interaction effect in subgroups of different BMI (p for interaction = 0.01).

CONCLUSIONS

Elevated ABSI is significantly associated with an increased risk of PCa, particularly among individuals who are under/normal weighted or obese.

Prevalence of allergen sensitization among children with allergic rhinitis in Changzhou, China: a retrospective observational study

OBJECTIVE

To determine the prevalence of sensitivity to common inhaled and food allergens among children with allergic rhinitis (AR) in Changzhou in eastern China and provide a basis for epidemiological research of pediatric allergic rhinitis and allergen avoidance in this region.

METHODS

This was a retrospective observational study, a total of 1248 children with AR were enrolled at the Third People's Hospital of Changzhou between January 2018 and December 2019. The serum-specific immunoglobulin E (sIgE) to 19 kinds of inhaled and food allergens and serum total IgE were detected with the AllergyScreen test (Mediwiss Analytic GmbH, Moers, Germany). All participants had a positive reaction to at least one allergen in the test (the sIgE concentration ≥ 0.35 IU/ml).

RESULTS

Among the patients, 818 (65.54%) were male and 430 (34.46%) were female, with 81 (6.50%) aged 1-3 year, 501 (40.14%) aged 4-7 year, and 666 (53.36%) aged 8-14 year. The positivity rate of inhaled allergens was 80.05% (n = 999), while the positivity rate of food allergens was 66.19% (n = 826). 828 patients (66.35%) were sensitized to multiple allergens. The most common inhaled allergens were Dermatophagoides pteronyssinus (65.38%), mold mix (25.56%), house dust (20.67%), and dog hair dander (13.94%), and the most common food allergens were cow's milk (30.31%), cashew nut (27.9%), egg (22.68%), and beef (12.98%). With an increase in age, the inhaled allergen positivity rate showed a significant increase (P < 0.01), while the food allergen positivity rate decreased significantly (P < 0.01). There were significant age differences in total IgE levels (P < 0.01) and the total IgE level was highest in the group aged 8-14 year.

CONCLUSIONS

Dermatophagoides pteronyssinus was the most common sensitizing allergen in pediatric patients with AR in Changzhou. Several other inhaled and food allergens were also common. We observed that multiple allergenic factors play an important role in the occurrence and development of AR.

Composite Hydrogel Modulates Intrinsic Immune-Cascade Neovascularization for Ocular Surface Reconstruction after Corneal Chemical Injury

Ocular alkali burns recruit neutrophils and triggers neutrophil extracellular trap (NET)-neovascularization cascade effects that limit ocular surface reconstruction and functional repair. However, effective inhibition of the release of neutrophil extracellular traps after a corneal chemical injury, coordination of intrinsic immunity with corneal repair, and exploration of more effective and non-invasive drug-delivery modes are still urgently needed. Using an in vitro coculture system, we found that an alkaline environment stimulates neutrophils to release NETs, which can be regulated by deoxyribonuclease I (DNase I). Inspired by this, we loaded DNase I, which effectively regulates NETs, onto chitosan nanoparticles and combined them with silk fibroin to construct a composite hydrogel that can sustainably regulate NETs. The hydrogel reduced neutrophil extracellular trap production by 50% and neovascularization by approximately 70% through sustained DNase I release after a corneal alkali burn. The complex hydrogel promotes ocular surface reconstruction by modulating the intrinsic immune-cascade neovascularization effect, providing a new research basis for the construction of nanobiomaterials that modulate pathological neovascularization.

Exosomes derived from mir-214-3p overexpressing mesenchymal stem cells promote myocardial repair

AIMS

Exosomes are known as nanovesicles that are naturally secreted, playing an essential role in stem-mediated cardioprotection. This study mainly focused on investigating if exosomes derived from miR-214 overexpressing mesenchymal stem cells (MSCs) show more valid cardioprotective ability in a rat model of acute myocardial infarction (AMI) and its potential mechanisms.

METHODS

Exosomes were isolated from control MSCs (Ctrl-Exo) and miR-214 overexpressing MSCs (miR-214OE-Exo) and then they were delivered to cardiomyocytes and endothelial cells in vitro under hypoxia and serum deprivation (H/SD) condition or in vivo in an acutely infarcted Sprague-Dawley rat heart. Regulated genes and signal pathways by miR-214OE-Exo treatment were explored using western blot analysis and luciferase assay. RESULTS IN VITRO: , miR-214OE-Exo enhanced migration, tube-like formation in endothelial cells. In addition, miR-214OE-Exo ameliorated the survival of cardiomyocytes under H/SD. In the rat AMI model, compared to Ctrl-Exo, miR-214OE-Exo reduced myocardial apoptosis, and therefore reduced infarct size and improved cardiac function. Besides, miR-214OE-Exo accelerated angiogenesis in peri-infarct region. Mechanistically, we identified that exosomal miR-214-3p promoted cardiac repair via targeting PTEN and activating p-AKT signal pathway.

CONCLUSION

Exosomes derived from miR-214 overexpressing MSCs have greatly strengthened the therapeutic efficacy for treatment of AMI by promoting cardiomyocyte survival and endothelial cell function.