Background
Non-small cell lung cancer (NSCLC) cells derived intracellular and extracellular programmed cell death ligand 1 (PD-L1) promoted cancer progression and drug resistance, and facilitated tumor immune evasion. However, the detailed molecular mechanisms are still largely unknown. In the present study, we aimed to explore the role of circular RNA circ-CPA4/let-7 miRNA/PD-L1 axis in the regulation of NSCLC progression, drug resistance and tumor immune microenvironment.
Methods
Real-Time qPCR and Western Blot analysis were conducted to examine gene expressions at transcriptional and translated levels, respectively. The regulatory mechanisms of circ-CPA4, let-7 miRNA and PD-L1 were validated by dual-luciferase reporter gene system and RNA pull-down assay. Cell growth and apoptosis were determined by CCK-8 assay, colony formation assay and Annexin V-FITC/PI double staining assay. Cell mobility was evaluated by transwell assay.
Results
Circ-CPA4 and PD-L1 were high-expressed, while let-7 miRNA was low-expressed in NSCLC cells and cancer tissues compared to the human bronchial epithelial (HBE) cells and their paired clinical normal adjacent tissues, respectively. Besides, knock-down of circ-CPA4 inhibited cell growth, mobility and epithelial-mesenchymal transition (EMT), and promoted cell death in NSCLC cells by downregulating PD-L1 through serving as a RNA sponge for let-7 miRNA. In addition, the NSCLC cells derived PD-L1-containing exosomes promoted cell stemness and increased resistance of NSCLC cells to cisplatin. Notably, by co-culturing the NSCLC cells with CD8
+
T cells isolated from human peripheral blood mononuclear cells (hPBMCs) in a transwell co-culturing system, we found that NSCLC cells inactivated CD8
+
T cells in a secreted PD-L1-dependent manner. Further results suggested that circ-CPA4 also positively regulated exosomal PD-L1, and the NSCLC cells with circ-CPA4 ablation re-activated CD8
+
T cells in the co-culturing system.
Conclusion
Taken together, circ-CPA4 regulated cell growth, mobility, stemness and drug resistance in NSCLC cells and inactivated CD8
+
T cells in the tumor immune microenvironment through let-7 miRNA/PD-L1 axis.
More efficient drug delivery system and formulation with less adverse effects are needed for the clinical application of broad-spectrum antineoplastic agent doxorubicin (DOX). Here we obtained outer-membrane vesicles (OMVs), a nano-sized proteoliposomes naturally released by Gram-negative bacteria, from attenuated
Klebsiella pneumonia
and prepared doxorubicin-loaded O0MVs (DOX-OMV). Confocal microscopy and
in vivo
distribution study observed that DOX encapsulated in OMVs was efficiently transported into NSCLC A549 cells. DOX-OMV resulted in intensive cytotoxic effects and cell apoptosis
in vitro
as evident from MTT assay, Western blotting and flow cytometry due to the rapid cellular uptake of DOX. In A549 tumor-bearing BALB/c nude mice, DOX-OMV presented a substantial tumor growth inhibition with favorable tolerability and pharmacokinetic profile, and TUNEL assay and H&E staining displayed extensive apoptotic cells and necrosis in tumor tissues. More importantly, OMVs’ appropriate immunogenicity enabled the recruitment of macrophages in tumor microenvironment which might synergize with their cargo DOX
in vivo
. Our results suggest that OMVs can not only function as biological nanocarriers for chemotherapeutic agents but also elicit suitable immune responses, thus having a great potential for the tumor chemoimmunotherapy.
Lung cancer has been proved to be one of the most common kinds of cancers around the globe. Meanwhile, as the predominant type of lung cancer, lung adenocarcinoma (LUAD) has received increasing attention in cancer research. Long noncoding RNAs (lncRNAs) are known to be associated with oncogenesis and progression of various cancers. However, many lncRNAs have not been thoroughly detected in LUAD. In this study, through bioinformatics analysis we found that zinc finger protein multitype 2 antisense RNA 1 (ZFPM2‐AS1) was associated with poor prognosis of LUAD patients. Also, ZFPM2‐AS1 was detected to be overexpressed in LUAD tissues and cells. Furthermore, ZFPM2‐AS1 could promote the proliferation of LUAD cells. Next, miR‐18b‐5p was found to bind with and negatively regulated by ZFPM2‐AS1. VMA21, target gene of miR‐18b‐5p, could bind with and be negatively regulated by miR‐18b‐5p. More importantly, both ZFPM2‐AS1 and VMA21 were found to be attached to the RNA‐induced silencing complex constructed from miR‐18b‐5p and Ago2. Also, ZFPM2‐AS1 could regulate the expression of VMA21. Therefore, ZFPM2‐AS1 were confirmed to regulate VMA21 by competitively binding with miR‐18b‐5p. Finally, rescue assays confirmed that ZFPM2‐AS1 could regulate LUAD cell proliferation via miR‐18b‐5p/VMA21 axis.
Background The outbreak of COVID-19 has led to international concern. We aimed to establish an effective screening strategy in Shanghai, China, to aid early identification of patients with COVID-19.
MethodsWe did a multicentre, observational cohort study in fever clinics of 25 hospitals in 16 districts of Shanghai. All patients visiting the clinics within the study period were included. A strategy for COVID-19 screening was presented and then suspected cases were monitored and analysed until they were confirmed as cases or excluded. Logistic regression was used to determine the risk factors of COVID-19.
Findings We enrolled patients visiting fever clinics fromJan 17 to Feb 16, 2020. Among 53 617 patients visiting fever clinics, 1004 (1•9%) were considered as suspected cases, with 188 (0•4% of all patients, 18•7% of suspected cases) eventually diagnosed as confirmed cases. 154 patients with missing data were excluded from the analysis. Exposure history (odds ratio [OR] 4•16, 95% CI 2•74-6•33; p<0•0001), fatigue (OR 1•56, 1•01-2•41; p=0•043), white blood cell count less than 4 × 10⁹ per L (OR 2•44, 1•28-4•64; p=0•0066), lymphocyte count less than 0•8 × 10⁹ per L (OR 1•82, 1•00-3•31; p=0•049), ground glass opacity (OR 1•95, 1•32-2•89; p=0•0009), and having both lungs affected (OR 1•54, 1•04-2•28; p=0•032) were independent risk factors for confirmed COVID-19.Interpretation The screening strategy was effective for confirming or excluding COVID-19 during the spread of this contagious disease. Relevant independent risk factors identified in this study might be helpful for early recognition of the disease.
AimTo seek accurate and credible correlation manner between gender, age, and obesity; and the severity of obstructive sleep apnea (OSA) in large-scale population.MethodsTotals of 1,975 male and 378 female OSA patients were sequentially recruited. Centralized covariant tendencies between age, body mass index (BMI), and waist hip ratio (WHR); and OSA severity, were explored in a gender-specific manner via multiple statistical analyses. The accuracies of observed correlations were further evaluated by adaptive multiple linear regression.ResultsAll of age, BMI, WHR, smoking, drinking, and OSA severity differed between males and females. BMI and WHR were positively and (approximately) linearly associated with OSA severity in both males and females. Restricted cubic spline analysis was more effective than was the Pearson correlation approach in correlating age with AHI, and provided age crossover points allowing further piecewise linear modeling for both males and females. Multiple linear regression showed that increasing age was associated with OSA exacerbation in males aged ≤40 years and in females aged 45–53 years. BMI, WHR, and diabetes were independently associated with OSA severity in males with age-group-specific pattern. In females, only BMI was associated with OSA severity at all ages.ConclusionsIn male patients, BMI and WHR are prominent risk factors for OSA exacerbation. Age and diabetes are associated with OSA severity in males of particular ages. In females, BMI is also a prominent risk factor for severe OSA, and OSA severity increased with age in the range 45–53 years.
The 5-day regimen of levofloxacin 750 mg daily is non-inferior to 7-14-day conventional regimen of 500 mg daily in clinical efficacy for treatment of mild to moderate Chinese CAP population. The short course regimen allows the reduction of antimicrobial drug exposure and is well tolerated.
Background: Newly identified lncRNA zinc finger protein, FOG family member 2 antisense RNA 1 (ZFPM2-AS1) is identified as an oncogenic gene. However, the role of ZFPM2-AS1 in small cell lung cancer (SCLC) is poorly comprehended. Methods: The expression of genes in SCLC tissues and cells was measured by qRT-PCR. Colony formation, EdU, CCK-8, transwell and wound healing as well as in vivo assays revealed the function of ZFPM2-AS1 in SCLC. ChIP, luciferase reporter, RIP and RNA pull down assays demonstrated the binding relation among genes. Results: ZFPM2-AS1 was significantly upregulated in SCLC tissues and cells. ZFPM2-AS1 deficiency attenuated SCLC cell proliferation, invasion and migration. In addition, ZFPM2-AS1 was transcriptionally activated by Yin Yang 1 (YY1) factor. Further, miR-3612 was confirmed as downstream miRNA of ZFPM2-AS1. Moreover, TNF receptor associated factor 4 (TRAF4) was the target gene of miR-3612 in SCLC. ZFPM2-AS1, miR-3612 and TRAF4 jointly constituted a competing endogenous RNA (ceRNA) network in SCLC. Finally, TRAF4 could countervail ZFPM2-AS1 downregulationmediated function on SCLC cell proliferation and invasion in vitro and tumor growth in vivo. Conclusion: Our study elucidated the oncogenic effect of ZFPM2-AS1 in SCLC progression, indicating it may be a therapeutic target for SCLC.
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