Environmental Toxicology最新文献

Breast cancer incidence and mortality rate in Cameroonian women is incredibly high, thus there is need for more effective therapy. Xylopia aethiopica dry fruits are traditionally used for both nutritional and medicinal purposes, including the management of diverse ailments such as cancer. This study evaluated the in vitro and in vivo anti-mammary cancer potential of X. aethiopica. The cytotoxic activity of the ethanolic extract of X. aethiopica dry fruits was assessed at different concentrations against MDA-MB 231 and MCF-7 cells using the MTT assay. Additionally, clone formation, apoptosis/necrosis, cell adhesion, cell migration, and chemotaxis were examined. Furthermore, the chemo-preventive potential of X. aethiopica dry fruit extract (XAE) was evaluated on breast tumors induced by DMBA in 42 female rats of age 45–55 days (~80 g). The normal (NOR) and negative (DMBA) control groups were daily treated with the vehicle, while the positive (Tamox) and test (XAE) groups were administered tamoxifen (3.3 mg/kg) and X. aethiopica extract (75, 150, and 300 mg/kg BW), respectively for 20 weeks. Parameters such as tumor volume and burden, tumor incidence, CA 15-3 serum level, inflammatory status, antioxidant and histopathology were evaluated. X. aethiopica significantly (p < 0.05) decreased ER+ (MCF-7) and ER− (MDA-MB 231) breast adenocarcinoma cell growth from 12.5 to 100 μg/mL after 72 h. At the 100 μg/mL concentration, clone formation, cell proliferation, and migration were notably decreased in MDA-MB 231 cells after 48 h, while there was an observed rise in cell adhesion to the collagen extracellular matrix. Additionally, there was a rise in apoptotic cell count (p < 0.01) and caspase-3 activity (p < 0.05) observed in MDA-MB 231 cells following exposure to XAE at 100 μg/mL. XAE, across all tested doses, demonstrated significant reductions in tumor incidence, burden, and volume, akin to tamoxifen, compared to untreated rats (DMBA). Furthermore, there was an elevation in antioxidants (SOD, CAT, and GSH) and a decrease in pro-inflammatory cytokines (INF-γ, TNF-α, IL-12, and IL-6) observed at all tested doses. Overall, X. aethiopica dry fruit displays anticancer potential through caspase-3-dependent apoptosis pathways, alongside antioxidant and anti-inflammatory activities.

Gastric cancer (GC) poses a significant global health challenge, demanding a detailed exploration of its molecular landscape. Studies suggest that exposure to environmental pollutants can lead to changes in microRNA (miRNA) expression patterns, which may contribute to the development and progression of GC. MiRNAs have emerged as crucial regulators implicated in GC pathogenesis. The largest GC serum miRNA dataset to date, comprising 1417 non-cancer controls and 1417 GC samples was used. We conducted a comprehensive analysis of miRNA expression profiles. Differential expression analysis, co-expression network construction, and machine learning models were employed to identify key serum miRNAs and their association with clinical parameters. Weighted Gene Co-expression Network Analysis (WGCNA) and immune infiltration analysis were used to validate the importance of the key miRNA. A total of 1766 differentially expressed miRNAs were identified, with miR-1290, miR-1246, and miR-451a among the top up-regulated, and miR-6875-5p, miR-6784-5p, miR-1228-5p, and miR-6765-5p among the top down-regulated. WGCNA revealed that modules M1 and M5 were significantly associated with GC subtypes and disease status. MiRNA-target gene network analysis identified prognostically significant genes TP53, EMCN, CBX8, and ALDH1A3. Machine learning models LASSO, SVM, randomforest, and XGBOOST demonstrated the diagnostic potential of miRNA profiles. Tissue and serum miR-187 emerged as an independent prognostic factor, influencing patient survival across clinical parameters. Gene expression and immune cell infiltration were different in tissues stratified by miR-187 expression. In summary, the integration of differential gene expression, co-expression analysis, and immune cell profiling provided insights into the molecular intricacies of GC progression.

Colorectal cancer (CRC) is a highly malignant tumor with hypoxia being a crucial feature during its progression. This study utilized multiple independent CRC cohorts for bioinformatics analysis and in vitro experiments to investigate the role of hypoxia-related subgroups in CRC. Machine learning was employed to construct risk features associated with this subgroup and further explore its therapeutic value in CRC. The study identified the GPNMB+ Macrophage (GPNMB+ Macr) subgroup as most relevant to hypoxia. GPNMB+ Macr showed significantly higher infiltration in tumor tissues compared to non-tumor tissues, increasing with CRC stage. High infiltration of GPNMB+ Macr was associated with poor prognosis in terms of overall and recurrence-free survival in CRC patients. GPNMB+ Macrophages exhibit M2-like characteristics and have the ability to promote 5-FU resistance, proliferation, and metastasis of CRC cells. The study developed the Hypoxia-Related Macrophage Risk Score (HMRS), which not only served as an independent prognostic factor for CRC patients but also demonstrated robust prognostic performance compared to 84 previously published prognostic features. Patients with low HMRS were sensitive to fluorouracil, oxaliplatin (FOLFOX), and anti-PD-1 immunotherapy, while those with high HMRS showed resistance. Additionally, HMRS was identified as an independent prognostic factor in other digestive tract tumors (hepatocellular carcinoma, pancreatic cancer, esophageal cancer, and gastric cancer), indicating potential extrapolation to other tumor types. In conclusion, GPNMB+ Macr promotes the malignant progression of CRC, and HMRS serves as a powerful predictive tool for prognosis, chemotherapy, and immunotherapy in CRC patients, aiding in improving the quality of survival.

Di (2-ethylhexyl) phthalate (DEHP) is an important plasticizer in industrial production, and its toxic effects on testes are widely recognized. Se-methylselenocysteine (SMC) is a major selenium compound found in selenium-rich plants, which possesses unique biological properties such as antioxidants. However, the effect of SMC on DEHP-induced testicular injury and the specific mechanism remains unknown. In this study, 50 mice were randomly divided into 5 groups and were given corn oil (Control), DEHP, low-dose SMC (L-SMC), moderate-dose SMC (M-SMC), or high-dose SMC (H-SMC). The sperm quality of the mice in each group was determined, and HE staining and transmission electron microscopy (TEM) were applied to observe testicular morphology, and testicular tissues were collected for the subsequent molecular biological analyses. The TM4 cell line was applied in vitro for mechanism validation. Our results showed that DEHP could lead to decreased sperm quality and blood–testis barrier damage in mice, which could be alleviated by SMC. Mitochondrial damage accompanied by accumulation of total iron content, MDA, and 4-HNE, as well as downregulation of antioxidants SOD, GSH, and GSH-Px were observed after DEHP treatment, which exhibited a typical ferroptosis feature. In vitro experiments confirmed that SMC promoted upregulation of GPX4 in TM4 cells and was able to alleviate DEHP metabolite MEHP-induced ferroptosis and promote the expression of cell junction key proteins ZO-1, Occludin, and Connexin 43, which could be inhibited by the GPX4 inhibitor RSL3 or the Nrf2 inhibitor ML385. Overall, the above results suggest that SMC ameliorates the DEHP-induced ferroptosis in testicular Sertoli cells, protects the blood–testis barrier, and prevents sperm aberrations via the Nrf2/GPX4 axis.

Zika virus (ZIKV) infection during pregnancy can lead to a set of congenital malformations known as Congenital ZIKV syndrome (CZS), whose main feature is microcephaly. The geographic distribution of CZS in Brazil during the 2015–2017 outbreak was asymmetrical, with a higher prevalence in the Northeast and Central-West regions of the country, despite the ubiquitous distribution of the vector Aedes aegypti, indicating that environmental factors could influence ZIKV vertical transmission and/or severity. Here we investigate the involvement of the most used agrochemicals in Brazil with CZS. First, we exposed human neuroblastoma SK-N-AS cells to the 15 frequently used agrochemical molecules or derivative metabolites able to cross the blood–brain barrier. We found that a derived metabolite from a widely used herbicide in the Central-West region, 2,4-dichlorophenoxyacetic acid (2,4D), exacerbates ZIKV neurotoxic effects in vitro. We validate this observation by demonstrating vertical transmission leading to microcephaly in the offspring of immunocompetent C57BL/6J mice exposed to water contaminated with 0.025 mg/L of 2,4D. Newborn mice whose dams were exposed to 2,4D and infected with ZIKV presented a smaller brain area and cortical plate size compared to the control. Also, embryos from animals facing the co-insult of ZIKV and 2,4D exposition presented higher Caspase 3 positive cells in the cortex, fewer CTIP2+ neurons and proliferative cells at the ventricular zone, and a higher viral load. This phenotype is followed by placental alterations, such as vessel congestion, and apoptosis in the labyrinth and decidua. We also observed a mild spatial correlation between CZS prevalence and 2,4D use in Brazil's North and Central-West regions, with R² = 0.4 and 0.46, respectively. Our results suggest that 2,4D exposition facilitates maternal vertical transmission of ZIKV, exacerbating CZS, possibly contributing to the high prevalence of this syndrome in Brazil's Central-West region compared to other regions.

Invasiveness and epithelial–mesenchymal transition (EMT) are main patterns of metastatic disease, which is the major cause cancer-related mortality in human malignant melanoma cells. Tea and its consumption extract are associated with a lower risk of several types of cancer and have anti-inflammatory and antioxidative biological effects. However, the anti-EMT and anti-cancer stemness effect of black tea ethanol extracts (BTEE) in human melanoma remain poorly understood. In this study, the effects of BTEE-reduced invasiveness, EMT, and cancer stemness were evaluated in human A 375 and A2058 melanoma cells. BTEE inhibited the activity of u-PA, migration, and invasiveness by repressing p-FAK signaling pathway. BTEE affected the EMT by downregulating the expression of β-catenin, N-cadherin, fibronectin, vimentin, and Twist-1. BTEE also reduced tumor necrosis factor-alpha (TNF-α)-induced invasiveness and cancer stemness characteristics in vitro. The growth of melanoma in nude mice xenograft model showed that BTEE suppressed A 375 tumor growth in vivo.

The Himalayan plant Inula racemosa has medicinal properties and can be used to prevent or treat cancer. This is because it contains certain chemicals that are known to fight cancer cells with few or no side effects. I. racemosa has been used for this purpose for many years in traditional medicine and has shown promising results. The present study was crafted to explore the suppressive impacts on cellular proliferation of the root extract derived from I. racemosa via in vivo experimentation. I. racemosa (IR) root extract was tested at three different doses (100, 250, and 500 mg/Kg BW) for 18 weeks to assess its anti-neoplastic activity against mammary tumors in female rats. The assessment included various parameters such as hematological and biochemical indices, tumor parameters, oxidative stress analysis, gross and histopathological lesion determination, Masson's trichrome staining, immunohistochemical expression of Ki-67, MMP-9, and VEGF in mammary gland tissues, and molecular docking. The chemopreventive action of IR root extract was demonstrated by the inhibition of tumor parameters (tumor size and tumor volume), minimum changes in the liver (ALT, AST, and ALP) and kidney enzymes (BUN and creatinine), declined lipid peroxidation activity, decline gross, and histological changes in mammary gland tumors, reduced expression of KI-67, MMP-9, and VEGF and maximum binding affinity of isoalantolactone with VEGF through molecular docking. The study suggests that the active constituents (isoalantolactone and alantolactone) of I. racemosa roots have anti-neoplastic activity against mammary tumors, making them a valuable therapeutic regimen for the future.