This study explored the mechanism underlying long non-coding RNA ROR regulating autophagy on Tamoxifen resistance in breast cancer. Cancer tissues and adjacent normal tissues were collected from 74 breast cancer patients. Human breast cancer BT474 cells were assigned into blank, phosphate buffered saline, Tamoxifen, negative control + Tamoxifen, siROR + Tamoxifen, 3-methyladenine + Tamoxifen, and siROR + 3-methyladenine + TA groups. The expression of long non-coding RNA ROR and expressions of multi-drug resistance-associated P-glycoprotein and glutathione S-transferase-π messenger RNA were detected using quantitative real-time polymerase chain reaction. The expressions of light chain 3, Beclin 1, multi-drug resistance-associated P-glycoprotein, and glutathione S-transferase-π protein were determined using western blotting. Cell proliferation, invasion, and migration abilities were measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Transwell assay, and scratch test, respectively. The long non-coding RNA ROR expression was higher in the breast cancer tissues than that in the adjacent normal tissues. Compared with the blank group, light chain 3 and Beclin 1 expressions were increased in the siROR + Tamoxifen group but decreased in the 3-methyladenine + Tamoxifen group; these data indicated that downregulated long non-coding RNA ROR promoted autophagy. In comparison with the blank group, multi-drug resistance-associated P-glycoprotein and glutathione S-transferase-π messenger RNA and protein expressions were reduced in the siROR + Tamoxifen group but elevated in the 3-methyladenine + Tamoxifen group, suggesting that downregulated long non-coding RNA ROR suppressed the drug resistance to Tamoxifen and the inhibition of autophagy reversed the effect of long non-coding RNA ROR on drug resistance. Compared with the Tamoxifen, negative control, and siROR + 3-methyladenine + Tamoxifen groups, the cell proliferation, invasion, and migration in the siROR + Tamoxifen group were much decreased; these results implied that downregulated long non-coding RNA ROR suppressed BT474 cell proliferation, invasion, and migration and reversed the effect of Tamoxifen on the BT474 cells. These results indicate that inhibition of long non-coding RNA ROR reverses resistance to Tamoxifen by inducing autophagy in breast cancer.
The clinical relevance of regulatory T cell (Treg) infiltration in breast cancer (BC) remains controversial, and no recent meta-analysis has been published on this subject. Our aim was to identify the precise relationship between Tregs and the prognosis and clinic-pathological features of BC. Eligible articles were identified with a MEDLINE database search over a period up to March 2015. Our meta-analysis was performed using STATA software 11.0 and Review Manager 5.3. The correlations between Treg infiltration and clinico-pathological features and BC prognosis were analyzed. Subgroup and sensitivity analyses, as well as meta-regression, were conducted. Eighteen published studies (including 8,562 patients) were eligible. Overall survival (OS) and disease-, recurrence-, and progression-free survival (DFS/RFS/PFS) were correlated with Treg infiltration (OR=2.03 (95% CI, 1.40-2.95; P=0.000) and 1.48 (95% CI, 1.00-2.19; P=0.050), respectively), including 3-, 5-, and 10-year mortality rates. In addition, low Treg infiltration was present in estrogen receptor (ER)-positive tumors (P=0.000), progesterone receptor (PR)-positive tumors (P=0.003), Her2-negative tumors (P=0.000) and histological grade I/II tumors (P=0.001). No publication bias was observed with the exception of OS. Subgroup analysis suggested that the mortality rate of the high Treg infiltration subgroup was increased compared with the low Treg infiltration subgroup among ER-positive patients. Treg infiltration indicated a poorer prognosis for BC and is related to ER, PR, and Her2 status and histological grade. Thus, Treg infiltration could help predict outcomes and guide clinical therapy.
Microglial activation has been suggested to be associated with the incidence of radiation-induced brain injury. The present study investigated the molecular mechanism(s) involved in radiation-induced activation of the microglia. Mouse microglial BV-2 cells were exposed to different doses of radiation. The release of inflammatory factors was evaluated by enzyme-linked immunosorbent assay and real-time reverse transcriptase polymerase chain reaction. Protein expression was determined by immunocytochemistry and immunoblotting. Microglial activation was induced by radiation [>16 Gray (Gy)]. Activated cells exhibited a stouter spherical morphology and the levels of ionized calcium-binding adapter molecule-1 and CD68 were considerably upregulated. The generation of inflammatory factors, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), IL-6, toll‑like receptor 8 (TLR-8) and cyclooxygenase 2 (COX-2), was increased and peaked at either 3 or 6 h after radiation treatment. Phosphorylated γ-histone 2A, member X (γ-H2AX), which facilitates DNA double-strand breaks (DSBs), was upregulated at 3 h post-radiation treatment. This was accompanied by the nuclear translocation of the nuclear factor-κB (NF-κB) p65 subunit. Moreover, 3 h following radiation treatment, the NF-κB essential modulator (NEMO) was markedly elevated, whereas the NF-κB regulatory inhibitor-α (IκB-α) was considerably decreased. Our results demonstrate that the NF-κB signaling pathway may trigger microglial activation and release of inflammatory factors following irradiation. These findings may provide valuable insight into understanding the molecular mechanism(s) involved in brain injury induced by radiation therapy.
In this study, we investigated the association between TP53 somatic mutations and immunotherapeutic outcomes in non-small cell lung cancer (NSCLC) patients. Kaplan-Meier survival curve analysis of the MSK-IMPACT cohort of 350 NSCLC patients shows that overall survival (OS) is significantly lower for patients with truncating TP53 mutations than those with wild-type TP53 (OS: 9 months vs. 14 months; P =0.019). Multivariate analysis shows that truncating TP53 mutations are an independent predictor of immunotherapeutic outcomes. Moreover, among NSCLC patients with lower tumor mutation burden (TMB), those with TP53 truncating mutations showed significantly lower OS than those with wild-type TP53 [hazard ratio (HR) = 1.40, confidence interval (CI) = 1.13-1.73; P = 0.002]. TP53 mutations correlate with higher infiltration of CD8 + T cells, neutrophils and dendritic cells in lung adenocarcinoma tissues. A prognostic model with TP53 mutational status shows better survival prediction than the model without TP53 mutational status 1-year [area under curve (AUC): 64.9% vs. 60.2%; P = 0.052] and 2-years (AUC: 70.9% vs. 66.1%; P = 0.098) post-immunotherapy. These findings demonstrate that truncating TP53 mutations correlate with poor immunotherapy outcomes in NSCLC patients with low TMB. TP53 mutation status also improves the prognostic prediction in NSCLC patients that underwent immunotherapy.
The effect of sodium nitroprusside (SNP; nitric oxide donor) treatment on wheat plant (Triticum aestivum L.) under drought stress during grain filling stage was investigated. When two cultivars wheat plants, Yumai No. 949 and Shanmai No. 5, were drought stressed by PEG for 72 h and rewatered for 48 h, the affections of osmotic dehydration and rehydration on the antioxidant enzymes activities and psbA gene transcriptional abundance were compared. Relative water contents (RWC) decreased markedly after 72 h of PEG stress, along with an obvious decrease in chlorophyll content, increase in SOD, CAT and APX activities, and MDA content as well. Real-time quantitative polymerase chain amplification indicated that drought stress also remarkably inhibited the transcription of psbA gene in photosystem II (PSII). All of these responses could be restored by removing of stress and applying another 48 h of rewatering. The exogenous 0.2 mmol l -1 SNP treatment could significantly alleviate the stress injury and accelerate the progress of recovery. Compared to Yumai No. 949, Shanmai No. 5 had less destroyed plasma membranes, higher RWC and chlorophyll contents, more psbA gene transcriptional abundance during water stress, and rapider recovery to control after rewatering, suggesting not only a better drought resistance but also a better recovery capability after a severe drought stress. The present results also suggested that the application of exogenous SNP could enhance the stress resistance of wheat plant during grain filling stage by increasing antioxidant enzymes activities, as well as protecting important gene transcription in PSII, which were to the benefit of functional recovery from drought stress.
The present study aimed to investigate the effect of the long noncoding RNA cancer susceptibility candidate 9 (CASC9) on doxorubicin (DOX)‑resistant breast cancer and to reveal the potential underlying mechanisms. The expression of CASC9 in breast cancer tissues and cell lines, in addition to drug‑resistant breast cancer cells (MCF‑7/DOX), was detected by reverse transcription‑quantitative polymerase chain reaction. Subsequently, MCF‑7/DOX cells were transfected with the silencing vector pS‑CASC9, containing enhancer of zeste homolog 2 (EZH2), multidrug resistance protein 1 (MDR1) or control small interfering (si)RNAs. The viability, apoptosis, migration and invasion of the transfected cells were assessed via an MTT assay, flow cytometry and a Transwell assay, respectively. The expression levels of apoptosis‑associated proteins (apoptosis regulator Bcl‑2, apoptosis regulator BAX, caspase‑3 and caspase‑9) were determined by western blotting. An RNA pull‑down assay was performed to identify CASC9‑binding candidates. In addition, the expression levels of the MDR1 gene and its encoded protein, P‑glycoprotein, were detected. CASC9 expression was upregulated in breast cancer tissues and cell lines, and drug‑resistant breast cancer cells. CASC9 knockdown significantly inhibited the growth and metastasis of drug‑resistant breast cancer cells, and decreased the half‑maximal inhibitory concentration DOX in MCF‑7/DOX cells. The RNA pull‑down assay revealed that CASC9 engaged EZH2; EZH2 siRNA significantly inhibited the cell growth, metastasis and chemoresistance of MCF‑7/DOX cells. Additionally, EZH2 may regulate the MDR1 gene. The present study demonstrated the oncogenic role of CASC9 in drug‑resistant breast cancer by binding to EZH2 and regulating the MDR1 gene. Modulation of CASC9 expression may be a promising target in the therapy of breast cancer and drug‑resistant breast cancer.
Radiation-induced brain injury (RIBI) is the most common adverse effect that occurs after cranial radiation therapy (CRT). We have previously reported that CRT-induced release of pro-inflammatory cytokines in brain tissues and inhibition of neurogenesis in the hippocampus might be caused by microglial activation and may play an important role in RIBI. In this study we examined the role of p53-induced protein with a death domain (PIDD) in radiation-induced activation of BV-2 cells. BV-2 cells were transfected with antisense oligonucleotide control mRNA or antisense oligonucleotide-targeted PIDD mRNA and were sham or 16 Gy irradiated. The state of microglia and expression of pro-inflammatory cytokines were detected using real-time polymerase chain reaction, Western blotting, immunofluorescence and flow cytometry. Findings from this study suggest that silencing PIDD expression could inhibit microglial activation by downregulating the PIDD-C/NF-κβ transcription pathway. PIDD acts as a critical switcher between the NF-κβ transcription pathway and radiation-induced apoptosis. Given these findings, this study offers a potential novel approach to further combination treatment of RIBI.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.