Synergistic Effect of Layered Double Hydroxides Nanodosage Form to Induce Apoptosis and Ferroptosis in Breast Cancer.

Background: Breast cancer is the most common cancer in women and one of the leading causes of cancer death worldwide. Ferroptosis, a promising mechanism of killing cancer cells, has become a research hotspot in cancer therapy. Simvastatin (SIM), as a potential new anti-breast cancer drug, has been shown to cause ferroptosis of cancer cells and inhibit breast cancer metastasis and recurrence. The purpose of this study is to develop a novel strategy boosting ferroptotic cascade for synergistic cancer therapy. Methods: In this paper, iron base form of layered double hydroxide supported simvastatin (LDHs-SIM) was synthesized by hydrothermal co-precipitation method. The characterization of LDHs-SIM were assessed by various analytical techniques, including ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). Biological activity, ferroptosis mechanism and biocompatibility were analyzed through in vivo and in vitro analysis, so as to evaluate its therapeutic effect on breast cancer. Results: The constructed LDHs-SIM nanosystem can not only release SIM through mevalonate (MVA) pathway, inhibit the expression of glutathione peroxidase 4 (GPX4), inhibit the expression of SLC7A11 and reduce the synthesis efficiency of GSH, but also promote the accumulation of Fe2+ in cells through the release of Fe3+, and increase the intracellular ROS content. In addition, LDHs-SIM nanosystem can induce apoptosis of breast cancer cells to a certain extent, and achieve the synergistic effect of apoptosis and ferroptosis. Conclusion: In the present study, we demonstrated that nanoparticles of layered double hydroxides (LDHs) loaded with simvastatin were more effective than a free drug at inhibiting breast cancer cell growth, In addition, superior anticancer therapeutic effects were achieved with little systemic toxicity, indicating that LDHs-SIM could serve as a safe and high-performance platform for ferroptosis-apoptosis combined anticancer therapy.

Glutathione-Responsive Polymersome with Continuous Glutathione Depletion for Enhanced Photodynamic Therapy and Hypoxia-Activated Chemotherapy.

The high glutathione (GSH) level of the tumor microenvironment severely affects the efficacy of photodynamic therapy (PDT). The current GSH depletion strategies have difficulty meeting the dual needs of security and efficiency. In this study, we report a photosensitizer Chlorin e6 (Ce6) and hypoxia-activated prodrug tirapazamine (TPZ) coloaded cross-linked multifunctional polymersome (TPZ/Ce6@SSPS) with GSH-triggered continuous GSH depletion for enhanced photodynamic therapy and hypoxia-activated chemotherapy. At tumor sites, the disulfide bonds of TPZ/Ce6@SSPS react with GSH to realize decross-linking for on-demand drug release. Meanwhile, the generated highly reactive quinone methide (QM) can further deplete GSH. This continuous GSH depletion will amplify tumor oxidative stress, enhancing the PDT effect of Ce6. Aggravated tumor hypoxia induced by PDT activates the prodrug TPZ, resulting in an enhanced combination of PDT and hypoxia-activated chemotherapy. Both in vitro and in vivo results demonstrate the efficient GSH depletion and potent antitumor activities by TPZ/Ce6@SSPS. This work provides a strategy for the design of a continuous GSH depletion platform, which holds great promise for enhanced combination tumor therapy.

Construction of a Robust Radiative Cooling Emitter for Efficient Food Storage and Transportation.

Nowadays, food safety is still facing great challenges. During storage and transportation, perishable goods have to be kept at a low temperature. However, the current logistics still lack enough preservation ability to maintain a low temperature in the whole. Hence, considering the temperature fluctuation in logistics, in this work, the passive radiative cooling (RC) technology was applied to package to enhance the temperature control capability in food storage and transportation. The RC emitter with selective infrared emission property was fabricated by a facile coating method, and Al2O3 was added to improve the wear resistance. The sunlight reflectance and infrared emittance within atmospheric conditions could reach up to 0.92 and 0.84, respectively. After abrasion, the sunlight reflection only decreased by 0.01, and the infrared emission showed a negligible change, revealing excellent wear resistance. During outdoor measurement, the box assembled by RC emitters (RC box) was proved to achieve temperature drops of ∼9 and ∼4 °C compared with the corrugated box and foam box, respectively. Besides, the fruits stored in the RC box exhibited a lower decay rate. Additionally, after printing with patterns to meet the aesthetic requirements, the RC emitter could also maintain the cooling ability. Given the superior optical properties, wear resistance, and cooling capability, the emitter has great potential for obtaining a better temperature control ability in food storage and transportation.

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.

Relationship between the circulating N-terminal pro B-type natriuretic peptide and the risk of carotid artery plaque in different glucose metabolic states in patients with coronary heart disease: a CSCD-TCM plus study in China.

OBJECTIVE: Circulating N-terminal pro B-type natriuretic peptide (NT-proBNP) is a marker for heart failure in patients with coronary heart disease (CHD) and associated with glycemic abnormalities. Studies on the association and diagnostic value of NT-proBNP in carotid plaques (CAP) in patients with CHD are limited. METHODS: The relationships between NT-proBNP and the risk of CAP in different glucose metabolic states, sexes, and age categories were also examined using 5,093 patients diagnosed with CHD. The NT-proBNP tertiles were used to divide patients into three groups in which the NT-proBNP levels, blood glucose levels, the occurrence of CAP, and the number and nature of CAP were measured using normoglycemic (NG), prediabetes (Pre-DM), and diabetes mellitus (DM) glucose metabolic statuses. Logistic regression analyses were used to compare the relationship between NT-proBNP and the risk of CAP occurrence and the number and nature of CAP. The diagnostic value of NT-proBNP for CAP risk was measured using receiver operating characteristic (ROC) curves. RESULTS: We found a 37% relative increase in the correlation between changes in NT-proBNP per standard deviation (SD) and the incidence of CAP. After adjusting for potential confounders, NT-proBNP at the T3 level was found to be associated with an increased CAP odds ratio (OR) when T1 was used as the reference. This relationship was also present in males, patients aged > 60 years, or both pre-DM and DM states. NT-proBNP was more likely to present as hypoechoic plaques at T1 and as mixed plaques at T3. We also measured the diagnostic accuracy of CAP for NT-proBNP in patients with CHD, with an AUC value of 0.627(95% CI 0.592-0.631), sensitivity of 50.7%, and specificity of 68.0%. CONCLUSION: An increase in NT-proBNP was significantly associated with the risk of CAP in patients with CHD, especially in males and patients aged > 60 years, and exhibited specific characteristics under different glucose metabolism states. Trial registration The study was approved by the Ethics Committee of Tianjin University of Traditional Chinese Medicine (Approval number TJUTCM-EC20210007) and certified by the Chinese Clinical Trials Registry on April 4, 2022 (Registration number ChiCTR2200058296) and March 25, 2022 by ClinicalTrials.gov (registration number NCT05309343).

Pseudouridine synthase 1 promotes hepatocellular carcinoma through mRNA pseudouridylation to enhance the translation of oncogenic mRNAs.

BACKGROUND AND AIMS: Pseudouridine is a prevalent RNA modification and is highly present in the serum and urine of patients with HCC. However, the role of pseudouridylation and its modifiers in HCC remains unknown. We investigated the function and underlying mechanism of pseudouridine synthase 1 (PUS1) in HCC. APPROACH AND RESULTS: By analyzing the TCGA data set, PUS1 was found to be significantly upregulated in human HCC specimens and positively correlated with tumor grade and poor prognosis of HCC. Knockdown of PUS1 inhibited cell proliferation and the growth of tumors in a subcutaneous xenograft mouse model. Accordingly, increased cell proliferation and tumor growth were observed in PUS1-overexpressing cells. Furthermore, overexpression of PUS1 significantly accelerates tumor formation in a mouse HCC model established by hydrodynamic tail vein injection, while knockout of PUS1 decreases it. Additionally, PUS1 catalytic activity is required for HCC tumorigenesis. Mechanistically, we profiled the mRNA targets of PUS1 by utilizing surveying targets by apolipoprotein B mRNA-editing enzyme 1 (APOBEC1)-mediated profiling and found that PUS1 incorporated pseudouridine into mRNAs of a set of oncogenes, thereby endowing them with greater translation capacity. CONCLUSIONS: Our study highlights the critical role of PUS1 and pseudouridylation in HCC development, and provides new insight that PUS1 enhances the protein levels of a set of oncogenes, including insulin receptor substrate 1 (IRS1) and c-MYC, by means of pseudouridylation-mediated mRNA translation.

Exosome-derived miR-372-5p promotes stemness and metastatic ability of CRC cells by inducing macrophage polarization.

Colorectal cancer (CRC) is the most common malignancy in the digestive system, and tumor metastasis is the main cause of death in clinical patients with CRC. It has been shown that exosomes promote phenotypic changes in macrophages and tumor metastasis in the CRC tumor microenvironment. In this study, we used miRNA-seq technology to screen out the highly expressed miR-372-5p among the miRNAs differentially expressed in plasma exosomes of clinical CRC patients. It was found that miR-372-5p highly expressed in HCT116 exosomes could be phagocytosed by macrophages and promote their polarization into M2 macrophages by regulating the PTEN/AKT pathway. Meanwhile, co-culture of CRC cells with conditioned medium (CM) of macrophages enhanced the EMT, stemness and metastasis of CRC cells. Mechanistically, CRC cells exosome-derived miR-372-5p induced polarized M2 macrophages to secrete chemokine C-X-C-Motif Ligand 12 (CXCL12), which activated the WNT/ß-catenin pathway to promote the EMT, stemness and metastatic ability of CRC cells. In summary, this study elucidated the molecular mechanism of exosomal miR-372-5p promoting metastasis and stemness in CRC, which may provide new therapeutic targets for CRC metastasis and prognosis assessment.

Long noncoding RNA study: Genome-wide approaches.

Long noncoding RNAs (lncRNAs) have been confirmed to play a crucial role in various biological processes across several species. Though many efforts have been devoted to the expansion of the lncRNAs landscape, much about lncRNAs is still unknown due to their great complexity. The development of high-throughput technologies and the constantly improved bioinformatic methods have resulted in a rapid expansion of lncRNA research and relevant databases. In this review, we introduced genome-wide research of lncRNAs in three parts: (i) novel lncRNA identification by high-throughput sequencing and computational pipelines; (ii) functional characterization of lncRNAs by expression atlas profiling, genome-scale screening, and the research of cancer-related lncRNAs; (iii) mechanism research by large-scale experimental technologies and computational analysis. Besides, primary experimental methods and bioinformatic pipelines related to these three parts are summarized. This review aimed to provide a comprehensive and systemic overview of lncRNA genome-wide research strategies and indicate a genome-wide lncRNA research system.

RNA-binding protein CCDC137 activates AKT signaling and promotes hepatocellular carcinoma through a novel non-canonical role of DGCR8 in mRNA localization.

BACKGROUND: RNA binding proteins (RBPs)-regulated gene expression play a vital role in various pathological processes, including the progression of cancer. However, the role of RBP in hepatocellular carcinoma (HCC) remains much unknown. In this study, we aimed to explore the contribution of RBP CCDC137 in HCC development. METHODS: We analyzed the altered expression level and clinical significance of CCDC137 in database and HCC specimens. In vitro cell assays and in vivo spontaneous mouse models were used to assess the function of CCDC137. Finally, the molecular mechanisms of how CCDC137 regulates gene expression and promotes HCC was explored. RESULTS: CCDC137 is aberrantly upregulated in HCC and correlates with poor clinical outcomes in HCC patients. CCDC137 markedly promoted HCC proliferation and progression in vitro and in vivo. Mechanistically, CCDC137 binds with FOXM1, JTV1, LASP1 and FLOT2 mRNAs, which was revealed by APOBEC1-mediated profiling, to increase their cytoplasmic localization and thus enhance their protein expressions. Upregulation of FOXM1, JTV1, LASP1 and FLOT2 subsequently synergistically activate AKT signaling and promote HCC. Interestingly, we found that CCDC137 binds with the microprocessor protein DGCR8 and DGCR8 has a novel non-canonical function in mRNA subcellular localization, which mediates the cytoplasmic distribution of mRNAs regulated by CCDC137. CONCLUSIONS: Our results identify a critical proliferation-related role of CCDC137 and reveal a novel CCDC137/DGCR8/mRNA localization/AKT axis in HCC progression, which provide a potential target for HCC therapy.

Colorectal cancer tumor cell-derived exosomal miR-203a-3p promotes CRC metastasis by targeting PTEN-induced macrophage polarization.

(1) Background: Tumor-associated macrophages (TAMs) are important immunocytes associated with liver metastasis of colorectal cancer (CRLM). However, the molecular processes underpinning the interaction between the TME and the tumour-derived exosomal miRNAs in CRLM are not being fully understood; (2) Methods: Transmission electron microscopy was utilized to confirm the existence of exosomes after differential ultracentrifugation. To determine the roles of exosomal miR-203a-3p, an in vivo and in vitro investigation was conducted. The mechanism by which exosomal miR-203a-3p governs the interaction between CRC cells and M2 macrophages was investigated using a dual-luciferase reporter assay, western blot, and other techniques; (3) Results: Overexpression of miR-203a-3p was associated with poor prognosis and liver metastasis in CRC patients. Exosomal miR-203a-3p was upregulated in the plasma of CRC patients and highly metastatic CRC cells HCT116, and it could be transported to macrophages via exosomes. Exosomal miR-203a-3p induced M2 polarization of macrophages by controlling PTEN and activating the PI3K/Akt signaling pathway. M2-polarized macrophages secreted the CXCL12, which increased cancer metastasis and resulted in pre-metastatic niches in CRLM by CXCL12/CXCR4/NF-κB signaling pathway. Co-culture of macrophages with miR-203a-3p-transfected or exosome-treated cells increased the ability of HCT116 cells to metastasize both in vitro and in vivo; (4) Conclusions: Exosomes produced by highly metastatic CRC cells and rich in miR-203a-3p may target PTEN and alter the TME, promoting liver metastasis in CRC patients. These findings offer fresh understanding of the liver metastatic process in CRC.

Astragaloside IV regulates TL1A and NF-κB signal pathway to affect inflammation in necrotizing enterocolitis.

AIM: This study aims to explore the possible effect of Astragaloside IV (AS-IV) on necrotizing enterocolitis (NEC) neonatal rat models and verify the possible implication of TNF-like ligand 1 A (TL1A) and NF-κB signal pathway. METHODS: NEC neonatal rat models were established through formula feeding, cold/asphyxia stress and Lipopolysaccharide (LPS) gavage method. The appearance, activity and skin as well as the pathological status of rats subjected to NEC modeling were assessed. The intestinal tissues were observed after H&E staining. The expression of oxidative stress biomarkers (SOD, MDA and GSH-Px) and inflammatory cytokines (TNF-α, IL-1ß and IL-6) were detected by ELISA and qRT-PCR. Western blotting and immunohistochemistry were applied to detect expressions of TL1A and NF-κB signal pathway-related proteins. Cell apoptosis was assessed by TUNEL. RESULTS: NEC neonatal rat models were established successfully, in which TL1A was highly expressed and NF-κB signal pathway was activated, while TL1A and NF-κB signal pathway can be suppressed by AS-IV treatment in NEC rats. Meanwhile, inflammatory response in intestinal tissues was increased in NEC rat models and AS-IV can attenuate inflammatory response in NEC rats through inhibiting TL1A and NF-κb signal pathway. CONCLUSION: AS-IV can inhibit TL1A expression and NF-κb signal pathway to attenuate the inflammatory response in NEC neonatal rat models.

5-HT modulates the properties of dendritic cells to interfere with the development of type 1 regulating T cells.

BACKGROUND: 5-hydroxytryptamine (5-HT, serotonin) is a major mediator in allergic reactions. The number of tolerogenic dendritic cell (tolDC) and regulatory T cell is reduced in allergic disorders. The mechanism is unclear. The objective of this study is to elucidate the role of 5-HT in interfering with tolDC generation and regulatory Type 1 T cell (Tr1 cell). METHODS: BALB/c mice were treated with 5-HT-containing nasal instillations. The frequency of tolDC and Tr1 cell was evaluated by flow cytometry. RESULTS: Following treatment with 5-HT nasal instillations for one week, the frequency of tolDC and Tr1 cell was significantly reduced in the respiratory tissues. Higher levels of SOS1 were detected in DCs isolated from the airway tissues of mice treated with 5-HT. A complex of SOS1 and c-Maf was detected in DCs in response to 5-HT stimulation. The expression of IL-10 was suppressed by the presence of 5-HT. The induction of Tr1 cell by DC was substantially compromised by 5-HT. CONCLUSIONS: 5-HT inhibits the expression of IL-10 in DCs. DCs primed with 5-HT lose the ability to induce Tr1 cells.

Cortisol synergizing with endoplasmic reticulum stress induces regulatory T-cell dysfunction.

The dysfunction of regulatory T cell (Treg) is associated with the pathogenesis of many immune diseases. The regiments used to re-establish Treg's function are currently unsatisfactory and need to be improved. The purpose of this study is to elucidate the synergistic effects of cortisol and endoplasmic reticulum (ER) stress on impairing regulatory T cell functions. In this study, blood samples were collected from patients with food allergy (FA). Immune cells were purified from blood specimens by flow cytometry. A mouse model of FA was established with ovalbumin as a specific antigen. We observed that serum cortisol levels of FA patients were negatively correlated with peripheral Treg counts. Overwhelmed ER stress status was detected in Tregs of FA patients. The antigen-specific immune response induced ER stress in Tregs, which was exacerbated by concurrent cortisol exposure. ER stress mediated the effects of cortisol on impairing the immune suppressive ability of Tregs. The expression of Rnf20 was observed in Tregs upon exposure to cortisol. Rnf20 reduced the expression of Foxp3 and transforming growth factor (TGF)-ß in Tregs. Rnf20 inhibition re-established the immunosuppressive functions of Tregs obtained in patients with FA. The experimental FA in mice was attenuated by inhibition of Rnf20 in Tregs. In summary, specific immune response in synergy with cortisol to induce the expression of Rnf20 in Tregs. Rnf20 reduces the levels of Foxp3 and TGF-ß to impair the immune suppressive function. Inhibition of Rnf20 can restore the immune suppressive ability of Tregs obtained from FA patients.

The Conserved LncRNA DIO3OS Restricts Hepatocellular Carcinoma Stemness by Interfering with NONO-Mediated Nuclear Export of ZEB1 mRNA.

Hepatocellular carcinoma (HCC) is an aggressive and fatal disease caused by a subset of cancer stem cells (CSCs). It is estimated that there are approximately 100 000 long noncoding RNAs (lncRNAs) in humans. However, the mechanisms by which lncRNAs affect tumor stemness remain poorly understood. In the present study, it is found that DIO3OS is a conserved lncRNA that is generally downregulated in multiple cancers, including HCC, and its low expression correlates with poor clinical outcomes in HCC. In in vitro cancer cell lines and an in vivo spontaneous HCC mouse model, DIO3OS markedly represses tumor development via its suppressive role in CSCs through downregulation of zinc finger E-box binding homeobox 1 (ZEB1). Interestingly, DIO3OS represses ZEB1 post-transcriptionally without affecting its mRNA levels. Subsequent experiments show that DIO3OS interacts with the NONO protein and restricts NONO-mediated nuclear export of ZEB1 mRNA. Overall, these findings demonstrate that the DIO3OS-NONO-ZEB1 axis restricts HCC development and offers a valuable candidate for CSC-targeted therapeutics for HCC.

Layered Double Hydroxide-Loaded miR-30a for the Treatment of Breast Cancer In Vitro and In Vivo.

MicroRNAs (miRNAs) play an essential role in cancer therapy, but the disadvantages of its poor inherent stability, rapid clearance, and low delivery efficiency affect the therapeutic efficiency. Loading miRNAs by nanoformulations can improve their bioavailability and enhance therapeutic efficiency, which is an effective miRNA delivery strategy. In this study, we synthesized layered double hydroxides (LDH), which are widely used as carriers of drugs or genes due to the characteristics of good biocompatibility, high loading capacity, and pH sensitivity. We loaded the suppressor oncogene miR-30a on LDH nanomaterials (LDH@miR-30a) and determined the mass ratio of miRNA binding to LDH by agarose gel electrophoresis. LDH@miR-30a was able to escape the lysosomal pathway and was successfully phagocytosed by breast cancer SKBR3 cells and remained detectable in the cells after 24 h of co-incubation. In vitro experiments showed that LDH@miR-30a-treated SKBR3 cells showed decreased proliferation and cell cycle arrest in the G0/G1 phase and LDH@miR-30a was able to regulate the epithelial-mesenchymal transition (EMT) process and inhibit cell migration and invasion by targeting SNAI1. Meanwhile, in vivo experiments showed that nude mice treated with LDH@miR-30a showed a significant reduction in their solid tumors and no significant impairment of vital organs was observed. In conclusion, LDH@miR-30a is an effective drug delivery system for the treatment of breast cancer.

Mechanically Switchable Multifunctional Device for Regulating Passive Radiative Cooling and Solar Heating.

Energy consumption during cooling and heating poses a great threat to the development of society. Thermal regulation, as switchable cooling and heating in a single platform, is therefore urgently demanded. Herein, a switchable multifunctional device integrating heating, cooling, and latent energy storage was proposed for temperature regulation and window energy saving for buildings. A radiative cooling (RC) emitter, a phase-change (PC) membrane, and a solar-heating (SH) film were connected layer by layer to form a sandwich structure. The RC emitter exhibited selective infrared emission (emissivity in the atmospheric window: 0.81, emissivity outside the atmospheric window: 0.39) and a high solar reflectance (0.92). Meanwhile, the SH film had a high solar absorptivity (0.90). More importantly, both the RC emitter and the SH film displayed excellent wear resistance and UV resistance. The PC layer can control the temperature at a steady state under dynamic weather conditions, which could be verified by indoor and outdoor measurements. The thermal regulation performance of the multifunctional device was also verified by outdoor measurements. The temperature difference between the RC and SH models of the multifunctional device could reach up to 25 °C. The as-constructed switchable multifunctional device is a promising candidate for alleviating the cooling and heating energy consumption and realizing energy saving for windows.

Expression, regulating mechanism and therapeutic target of KIF20A in multiple cancer.

Kinesin family member 20A (KIF20A) is a member of the kinesin family. It transports chromosomes during mitosis, plays a key role in cell division. Recently, studies proved that KIF20A was highly expressed in cancer. High expression of KIF20A was correlated with poor overall survival (OS). In this review, we summarized all the cancer that highly expressed KIF20A, described the role of KIF20A in cancer. We also organized phase I and phase II clinical trials of KIF20A peptides vaccine. All results indicated that KIF20A was a promising therapeutic target for multiple cancer.

Exosomal lncRNA NEAT1 induces paclitaxel resistance in breast cancer cells and promotes cell migration by targeting miR-133b.

The lncRNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) has been associated with the development, metastasis and drug resistance of breast cancer (BC). However, the mechanisms underlying NEAT1-induced paclitaxel resistance in the microenvironment of BC remain unclear. In this study, NEAT1 expression was found to be high in paclitaxel-resistant BC cells (SKBR3/PR cells) and exosomes derived from these cells. NEAT1 promoted the migration of BC cells and their resistance to paclitaxel, whereas its downregulation reduced the drug resistance. In addition, downregulation of NEAT1 decreased the migration and proliferation of BC cells by inhibiting the expression of CXCL12 by reducing the adsorption of miR-133b. Furthermore, inhibition of miR-133b reversed the interference of NEAT1 and CXCL12 in paclitaxel resistance, migration and proliferation of BC cells. Knockdown of NEAT1 in a xenograft-bearing mouse model remarkably inhibited cancer progression and improved the response to paclitaxel. Altogether, this study revealed that SKBR3/PR cell-derived exosomal lncRNA NEAT1 can induce paclitaxel resistance and cell migration and growth in the tumour microenvironment of BC and may serve as a new target for the clinical treatment of BC.

miR-142-3p improves paclitaxel sensitivity in resistant breast cancer by inhibiting autophagy through the GNB2-AKT-mTOR Pathway.

Breast cancer has overtaken lung cancer as the most prevalent cancer worldwide. The development of advanced drug resistance inhibits the efficacy of paclitaxel(PTX)as a first-line chemotherapeutic agent for breast cancer. Autophagy and microRNAs (miRNAs) play a key role in chemoresistance. This study investigated the miR-142-3p effect on PTX resistance by regulating autophagy. A PTX-resistant breast cancer cell line was constructed, and miR-142-3p and G protein beta polypeptide 2 (GNB2) were filtered out using RNA sequencing and protein microarray analysis. The study revealed that miR-142-3p expression was lower in drug-resistant cells compared parental cells. Higher miR-142-3p expression inhibited the viability, migration, and autophagic flux of drug-resistant cells, while promoting apoptosis and sensitivity to PTX treatment. Mechanistically, miR-142-3p was found to amend PTX resistance by targeting GNB2, further revealing that the knockdown of GNB2 expression could activate the AKT-mTOR pathway. This study suggests that GNB2 is an essential target for miR-142-3p to restrain autophagy, providing a new reference value for improving breast cancer PTX treatment.

MicroRNA-640 Inhibition Enhances the Chemosensitivity of Human Glioblastoma Cells to Temozolomide by Targeting Bcl2 Modifying Factor.

Glioblastoma (GBM) is the most malignant and challenging type of astrocytoma and also notoriously acknowledged as the most common primary brain tumor globally. Currently, chemotherapy is the most master therapy for tumor and is essential in clinical treatment for GBM. Nevertheless, the characterization of chemotherapy resistance seriously hinders clinical chemotherapy treatment. Accordingly, there are imperious demands for the exploitation of novel chemosensitizer to promote the efficacy of chemotherapy. Our current study was conducted to probe into the potential impacts of microRNA (miR)-640 on the chemosensitivity in GBM and the associated underlying mechanism. Initially, TargetScan software was utilized to predict the targeted genes of miR-640, and the target relationship between miR-640 and Bcl-2-modifying factor (BMF) was validated by double luciferase report assay. Additionally, to explore the role of miR-640/BMF in U251 cells, miR-640 inhibitor/BMF-siRNA was used. U251 cells were processed with 100 µM temozolomide (TMZ) and detected with CCK-8 kit. Eventually, RT-qPCR and Western blotting were used for evaluating Bcl-2, Bax mRNA, and protein expression level. Flow cytometry analysis was performed to measure cellular apoptosis. Initially, the results indicated that BMF was the target gene of miR-640. MiR-640 negatively regulated BMF expression in GBM cells. Besides, the findings revealed that miR-640 inhibition significantly inhibited U251 cell proliferation, promoted cell apoptosis, and increased the sensitivity of GBM cells to TMZ by targeting BMF. Moreover, BMF overexpression significantly suppressed U251 cell proliferation, induced cell apoptosis, and increased the sensitivity of GBM cells to TMZ. Inhibition of miR-640 expression enhances chemosensitivity of human GBM cells to TMZ by targeting BMF.