miR-144-3p aggravated cartilage injury in rheumatoid arthritis by regulating BMP2/PI3K/Akt axis.

OBJECTIVES: Present study aimed to illustrate the role of miR-144-3p in rheumatoid arthritis (RA). METHODS: N1511 chondrocytes were stimulated by interleukin (IL)-1ß to mimic RA injury model in vitro. Rats were subjected to injection of type II collagen to establish an in vivo RA model, and the arthritis index score was calculated. Cell viability was determined by Cell Counting Kit-8. The expression of cartilage extracellular matrix proteins (collagen II and aggrecan) and matrix metalloproteinase protein were determined by quantitative real-time polymerase chain reaction and western blots. Cell apoptosis was measured by flow cytometry. Enzyme-linked immunosorbent assay was applied to test the secretion of pro-inflammatory cytokines (IL-1ß and tumour necrosis factor-α). Tissue injury and apoptosis were detected by haematoxylin-eosin staining and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling assay staining. Interaction of miR-144-3p and bone morphogenetic protein 2 (BMP2) was verified by dual-luciferase assay. RESULTS: miR-144-3p was dramatically increased in IL-1ß-induced N1511 cells. miR-144-3p depletion elevated cell viability, suppressed apoptosis, pro-inflammatory cytokine releasing, and extracellular matrix loss in IL-1ß-induced N1511 cells. Moreover, miR-144-3p targeted BMP2 to modulate its expression negatively. Activation of phosphatidylinositol 3-kinase (PI3K)/Akt signalling compromised inhibition of BMP2 induced aggravated N1511 cell injury with IL-1ß stimulation. Inhibition of miR-144-3p alleviated cartilage injury and inflammatory in RA rats. CONCLUSION: Collectively, miR-144-3p could aggravate chondrocyte injury inflammatory response in RA via BMP2/PI3K/Akt axis.

Diagnostic value of neutrophil-to-lymphocyte, lymphocyte-to-monocyte and platelet-to-lymphocyte ratio among patients with COVID-19 pneumonia: A retrospective study.

Objectives: Our study was aimed to investigate the clinical characteristics of the patients with COVID-19 pneumonia and research new diagnostic methods for the disease. Methods: In this retrospective study, medical records of 46 novel coronavirus-infected pneumonia (NCIP) patients and 30 healthy individuals in the two multiple hospitals from January 2020 to March 2020 were studied. Clinical characteristics, chest computed tomographic (CT) scans, medicine treatment and laboratory information were collected and retrospectively analyzed. Neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR) and platelet-to-lymphocyte ratio (PLR) were evaluated. Results: The main symptoms of the patients with NCIP were fever (100%), cough (82.6%), anorexia (37%), expectoration (34.8%) and fatigue (21.7%), dyspnea (15.2%). Ground glass opacity (GGO) with patch shadow was the main observation of the CT imaging (43.4%), followed by GGO (21.7%), patch shadow (19.5%), GGO with consolidation (8.7%) and GGO with reticular pattern (2.1%). The median white blood cell (WBC) count, lymphocyte count, platelet, and lymphocyte-monocyte ratio (LMR) in NCIP group were all significantly lower than in control group (p<0.001, for all comparisons), while the median neutrophil-monocyte ratio (NLR) and platelets-monocyte ratio (PLR) were both significantly higher (p<0.001, for both comparisons). Median WBC count, lymphocyte count, and platelet count on discharge were significantly higher than on admission (p<0.05). Median PLR was significantly lower two weeks after discharge (p<0.001), while NLR remained the same. The area under the curve (AUC) value of WBC, lymphocyte and platelet counts, NLR, LMR and PLR were 0.766, 0.931, 0.655, 0.780, 0.847 and 0.845, respectively. Early stages of the disease were associated with quick changes in WBC, lymphocyte, and platelet levels. However, NLR did not recover even two weeks after the discharge. Conclusion: Changes in WBC, lymphocyte, and platelet counts, as well as NLR, LMR and PLR are strongly associated with COVID-19 pneumonia. Monitoring blood markers may assist in evaluating the progression of the disease.

Circ_0074027 contributes to the progression of non-small cell lung cancer via microRNA-362-3p/clathrin heavy chain axis.

Circular RNAs are involved in the occurrence and development of different types of cancers. We aimed to illustrate the expression profile and mechanism of circ_0074027 in non-small cell lung cancer (NSCLC). Quantitative real-time PCR was employed to detect the expression of circ_0074027, paired like homeodomain 1 (PITX1) mRNA (mPITX1) and microRNA-362-3p (miR-362-3p). Western blot assay was utilized to measure the levels of clathrin heavy chain (CLTC), cyclin D1, BCL2-associated X, apoptosis regulator Bax (Bax), vimentin and matrix metallopeptidase 9. The clonogenicity, apoptosis and metastasis of NSCLC cells were examined by colony formation assay, flow cytometry and transwell migration and invasion assays. The target relationship between miR-362-3p and circ_0074027 or CLTC was predicted by starBase website and was validated by dual-luciferase reporter assay. Murine xenograft assay was applied to explore the function of circ_0074027 in vivo. We found that The enrichment of circ_0074027 and CLTC protein was elevated, and a significant reduction in the expression of miR-362-3p was observed in NSCLC tissues and cells relative to adjacent normal tissues and human bronchial epithelial cells 16HBE. Circ_0074027 possessed a stable circular structure. Circ_0074027 and CLTC could accelerate the colony formation and metastasis and suppress the apoptosis of NSCLC cells. Circ_0074027/miR-362-3p/CLTC axis was first found to regulate the malignance of NSCLC cells. The biological influence caused by circ_0074027 depletion on NSCLC cells was alleviated by the accumulation of CLTC. Circ_0074027 acted as an oncogene to promote the growth of NSCLC tumors in vivo. In conclusion, Circ_0074027 contributed to the progression of NSCLC through promoting the proliferation and motility while hampering the apoptosis of NSCLC cells via miR-362-3p/CLTC axis.

LncRNA CHRF promotes TGF-ß1 induced EMT in alveolar epithelial cells by inhibiting miR-146a up-regulating L1CAM expression.

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a type of progressive lung fibrosis disease. The survival time of diagnosed IPF patients is often only 2 years. Currently much evidence showed that the epithelial-mesenchymal transition (EMT) process is the main cause of the occurrence and development of IPF. LncRNA cardiac hypertrophy related factor (CHRF) was reported to be related with IPF development. Here we explored the functions and regulatory mechanisms of CHRF on EMT in IPF. MATERIALS AND METHODS: A549 cells were treated with transforming growth factor-ß1 (TGF-ß1) for 48 h to construct IPF cell model. CHRF and miR-146a expression were quantified using qPCR. The expression of L1 cell adhesion molecule (L1CAM) and EMT related indicators (E-cadherin, Vimentin, Slug and N-cadherin) were detected by qPCR and western blot. Dual luciferase reporter experiment was conducted to prove the molecular interaction of miR-146a and L1CAM, as well as CHRF and miR-146a. RESULTS: CHRF and L1CAM expression were significantly upregulated and promoted the EMT process in A549 after treatment of TGF-ß1. MiR-146a was obviously down-regulated, and knockdown of CHRF inhibited the EMT process by up-regulating miR-146a, in A549 after treatment of TGF-ß1. Meanwhile, overexpression of miR-146a inhibited EMT process via targeting L1CAM. In addition, L1CAM overexpression eliminated the inhibitory effect of sh-CHRF on the EMT process. CONCLUSIONS: These results provided evidence that CHRF promoted EMT process in A549 after treatment of TGF-ß1, which proposed a new insight for depth understanding the pathological mechanisms of IPF.

[Pirfenidone Inhibits Cytokines/chemokines Release from Alveolar Macrophages].

Objective To investigate the effect of pirfenidone on cytokine/chemokine production by alveolar macrophages(AMs)in patients with idiopathic nonspecific interstitial pneumonia(iNSIP)or idiopathic pulmonary fibrosis(IPF).Methods We prospectively enrolled 10 iNSIP patients,11 IPF patients,and 8 non-interstitial lung disease(non-ILD)patients(control group)from our center from January 2015 to December 2018.AMs from bronchoalveolar lavage fluid(BALF)were cultured with or without lipopolysaccharide(LPS)stimulation.The production of Th1 cytokines [soluble tumor necrosis factor receptor(sTNFR)-1,sTNFR-2,and interleukin(IL)-1ß],Th2 cytokines [IL-10 and granulocyte-macrophage colony-stimulating factor(GM-CSF)],angiogenic chemokines [IL-18 and macrophage inflammatory protein(MIP)-1ß],and angiostatic chemokines [interferon-gama inducible monokines(MIG)and interferon-gama inducible protein(IP-10)] in the culture supernatants were measured by a bead-based assay,Luminex.The effect of pirfenidone on the cytokine/chemokine production was tested at various concentrations(0,0.03,0.10,0.30 mg/ml).Results The spontaneous and LPS-stimulated release of TNF-α,sTNFR-1,sTNFR-2,IL-1ß,IL-10,MIP-1ß,MIG,and IP-10 by AMs were significantly increased in iNSIP and IPF groups compared with control group(all P<0.05),but no difference in IL-18 was seen among three groups(all P>0.05).MIG and IP-10 were significantly higher in iNSIP group than in IPF group(both P<0.05).Pirfenidone suppressed the spontaneous and LPS-stimulated AMs release of all studied cytokine/chemokine in iNSIP and IPF in a dose-dependent manner at concentrations of 0.10 and 0.30 mg/ml,and no difference was observed between iNSIP and IPF groups(both P>0.05).Conclusion Pirfenidone can markedly suppress cytokine/chemokine expression in iNSIP and IPF patients,but the difference is not significant between these two groups of patients.

Capillarisin exerts antiasthmatic activity in neonatal rats via modulating the matrix remodeling.

The use of phytochemical plays a major role in recent therapeutic regimens. Amongst, Capillarisin (CPS), an active chemical constituent of Artemisia capillaris was found to exert anti-inflammatory and antioxidant properties. However, the protective role of CPS has not been identified against neonatal asthma. Hence, in the present study, Wistar rats were used consisting of four groups such as control, asthma-induced, CPS-pretreated asthma animals, and CPS control. At the end of the experimental period, histology of the lungs, inflammatory cell counts in bronchoalveolar lavage fluid (BALF), inflammatory markers such as interleukin (IL) -6, IL-5, IL-4, and IL-13 were measured. Results demonstrated a significant restoration in alveolar thickening and reduced goblet cell hyperplasia with suppressed inflammatory cells. Moreover, a significant reduction in leukocyte infiltration in BALF lessened hyper responsiveness, and serum IgE levels of CPS treated group. Furthermore, the CPS administration alleviated the expression levels of IL-6, IL-17, IL-4 and IL-13 compared to the asthma-induced group. To an extent, the study elicited the extra cellular matrix protein expression in the asthma-induced animals, and the results demonstrated a profound reduction in the fibrotic markers was evidenced in CPS treated animals. Thus, the results of the present investigation propose that capillarisin can be a new medicine target for the treatment of asthma-mediated complications.

[Clinical value of surfactant protein-A in exudate pleural effusion].

OBJECTIVE: To evaluate the clinical value of surfactant protein-A (SP-A) in exudate pleural effusion (EPE).
 Methods: This clinical study was prospective, observational and cross-sectional. Two hundred and fifteen patients with pleural effusion were divided into the transudate pleural effusions (TPE) group and the EPE group. TPE patients served as the control group. The concentrations of pleural effusions SP-A (SP-Apl) and serum SP-A (SP-Ase) were measured by ELISA, and receiver operator characteristic (ROC) curve and multivarate Cox analysis of SP-A was analysed for its clinical value.
 Results: SP-Apl concentrations in the EPE group were significantly higher than that in the TPE group [(189.8±43.4) ng/mL vs (22.3±5.1) ng/mL, P<0.01]; SP-Ase concentrations in the EPE group were higher than that in the TPE group [(78.9±11.3) ng/mL vs (25.8±12.4) ng/mL, P<0.05]; SP-Apl concentrations were significantly higher than the concentrations of SP-Ase in the EPE group (P<0.01). In EPE group, SP-Apl and SP-Ase concentration in the patients with primary lung adenocarcinomas were the highest. The cut off value of SP-Apl concentrations was more than 484.5 ng/mL, yielding a 85.4% sensitivity and 95.2% specificity for diagnosing primary lung adenocarcinomas, with an area under the curve (AUC) of 0.943 (95% CI 0.852 to 0.934, P<0.01); when SP-Ase concentration was more than 84.2 ng/mL, it yielded a 76.4% sensitivity and 94.3% specificity for diagnosing primary lung adenocarcinomas, with an AUC of 0.910 (95% CI 0.921 to 0.953, P<0.01).
 Conclusion: While SP-Apl concentration is more than 484.5 ng/mL and/or SP-Ase concentration is more than 84.2 ng/mL, it may be helpful for the diagnosis of primary lung adenocarcinomas with the usage of pleural effusion.

Serum YKL-40 as predictor of outcome in hypersensitivity pneumonitis.

YKL-40, a chitinase-like protein mainly secreted by macrophages, neutrophils and epithelial cells, is increased in patients with idiopathic interstitial pneumonia and sarcoidosis. We aimed to investigate the role of YKL-40 as a biomarker in hypersensitivity pneumonitis (HP).72 HP patients, 100 interstitial lung disease (ILD) controls and 60 healthy controls were studied. YKL-40 was measured by ELISA in serum and bronchoalveolar lavage fluid (BALF) at baseline and follow-up. The relationship between YKL-40 levels, clinical variables and disease outcome was evaluated.Baseline serum YKL-40 levels were significantly higher in HP patients than in healthy controls (p<0.001), but lower than in patients with other ILDs. Baseline BALF YKL-40 levels in HP patients were the highest among ILD patients. In HP patients, serum YKL-40 correlated with the diffusing capacity of the lung for carbon monoxide at baseline (p<0.01) and over time (p<0.001). HP patients whose disease progressed or who died had higher baseline YKL-40 levels than those who remained stable and survived (p<0.001). At a cut-off of 119 ng·mL-1, the baseline serum YKL-40 level predicted disease progression (hazard ratio 6.567; p<0.001), and at a cut-off of 150 ng·mL-1 was associated with mortality (hazard ratio 9.989; p<0.001).Serum YKL-40 may be a useful prognostic biomarker in HP patients.

Serum YKL-40 is a reliable biomarker for pulmonary alveolar proteinosis.

BACKGROUND AND OBJECTIVE: Pulmonary alveolar proteinosis (PAP) is a rare disease characterized by alveolar filling. YKL-40, a chitinase-like protein produced by macrophages and epithelial cells, is increased in patients with interstitial lung diseases. We aimed to evaluate the role of YKL-40 as a biomarker for PAP. METHODS: A total of 34 patients with autoimmune PAP and 50 healthy controls were studied. YKL-40 was measured by ELISA in serum and bronchoalveolar lavage fluid (BALF). Chitinase coding gene polymorphisms (CHI3L1-329 and -131) were detected by PCR and pyrosequencing. Correlations between serum YKL-40 levels and disease outcome were analysed. RESULTS: Baseline serum and BALF levels of YKL-40 were higher in PAP patients than in controls (286 ± 27 ng/mL vs 42 ± 4 ng/mL, P < 0.0001; 323 ± 36 ng/mL vs 3 ± 1 ng/mL, P < 0.0001, respectively). Serum YKL-40 levels correlated with diffusing capacity of the lung for carbon monoxide (DLCO ) at baseline (P = 0.002) and over time (P < 0.0001). Patients with disease progression had higher baseline serum YKL-40 levels than those who remained stable or improved (P < 0.0001). A baseline cut-off level of 300 ng/mL was predictive of disease progression (HR (hazard ratio): 7.875, P = 0.001). The presence of the G allele was associated with higher serum and BALF levels of YKL-40. CONCLUSION: YKL-40 is elevated in serum and BALF of PAP patients, and may be of clinical utility to predict outcome in PAP.

Endothelin-1 Upregulates the Expression of High Mobility Group Box 1 in Human Bronchial Epithelial Cells.

Both endothelin-1 (ET-1) and high mobility group box 1 (HMGB1) reportedly are closely involved in the pathogenesis of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). In this study, we explored the regulatory effects of ET-1 on the expression of HMGB1 in human bronchial epithelial cells (HBEpCs). Primary HBEpCs were treated with ET-1 with or without transcription inhibitor actinomycin D, ETA receptor blocker BQ123, ETB receptor blocker BQ788, focal adhesion kinase (FAK) inhibitor or shRNA, or different kinase inhibitors. ET-1 increased the HMGB1 mRNA level in a statistically significant dose- and time-dependent manner within 8 hours of treatment, which was reflected in the dose-dependent induction of the HMGB1 protein level and the FAK activity. BQ123 and FAK inhibitor or shRNA, but not BQ788, completely abolished the promoting effect of ET-1 on the expression of HMGB1. Luciferase reporter assays revealed that neither ET-1 nor ETA nor FAK inhibition had any significant effect on the HMGB1 gene promoter activity. In the presence of the transcription inhibitor actinomycin D, the HMGB1 mRNA level markedly decreased over time, and ET-1 dose-dependently rescued the HMGB1 mRNA level. This effect of ET-1 was completely abolished by BQ123 and FAK inhibitor or shRNA, but not by BQ788. In conclusion, this study provides the first evidence that ET-1 upregulates the expression of HMGB1 in HBEpCs by increasing the stability of HMGB1 mRNA via the ETA receptor by a FAK-dependent mechanism. It adds new insights into the molecular mechanisms underlying ALI/ARDS.

Stattic alleviates pulmonary fibrosis in a mouse model of rheumatoid arthritis-relevant interstitial lung disease.

Approximately 20% of rheumatoid arthritis (RA) patients have RA-related interstitial lung disease (RA-ILD). Stattic, an STAT3 inhibitor, has been confirmed to be relevant to both RA and ILD. Therefore, this study explored the effect of Stattic on the progression of joint disease and pulmonary fibrosis in zymosan-treated female SKG mice, an established model for autoimmune arthritis. The experimental mice developed pulmonary interstitial pneumonia, which is similar to human cellular and fibrotic nonspecific interstitial pneumonia. Oral gavage of Stattic (60 mg/kg/d) was initiated 10 weeks after zymosan injection. Arthritis and lung fibrosis outcome scores decreased significantly following Stattic treatment. An obvious decrease in lung collagen levels, measured using hydroxyproline level determination and collagen staining, was detected after 6 weeks in Stattic-exposed mice with established disease. Stattic also dramatically restricted arthritis progression, based on joint evaluation. Transforming growth factor beta 1 (TGF-ß1) is a pivotal fibrosis-causing cytokine, used here to treat myofibroblasts, thereby establishing a lung fibrosis cell model. Stattic treatment can mitigate the TGF-ß1-triggered inflammatory response, myofibroblast activation, oxidative stress, and hyperproliferation by modulating the JAK1/STAT3 pathway. Our observations support a direct role of Stattic-inhibited STAT3 activation in lung fibrosis, which may be particularly relevant in the RA-ILD context.

Bone marrow mesenchymal stem cell-derived exosomes alleviate skin fibrosis in systemic sclerosis by inhibiting the IL-33/ST2 axis via the delivery of microRNA-214.

Interleukin (IL)- 33 is a tissue-derive proinflammatory cytokine that promotes fibrosis in systemic sclerosis (SSc). microRNA (miR)- 214 expression has been elaborated to be downregulated in SSc patients and exert anti-fibrotic and anti-inflammatory effects. This study elucidates the role of bone marrow mesenchymal stem cell-derived exosome (BMSC-Exos)-delivered miR-214 in SSc and the relationship between this miR and IL-33/ST2 axis. SSc clinical samples were obtained to evaluate levels of miR-214, IL-33, and ST2. Primary fibroblasts and BMSC-Exos were extracted, followed by the co-culture of PKH6-labeled BMSC-Exos and fibroblasts. Subsequently, Exos extracted from miR-214 inhibitor-transfected BMSCs were co-cultured with TGF-ß1-stimulated fibroblasts, after which the expression of fibrotic markers, miR-214, IL-33, and ST2, as well as fibroblast proliferation and migration, was determined. A skin fibrosis mouse model was induced with bleomycin (BLM) and treated with BMSC-Exos. Collagen fiber accumulation, collagen content, α-SMA expression, and IL-33 and ST2 levels were examined in BLM-treated or IL-33-knockout mice. IL-33 and ST2 were upregulated and miR-214 was downregulated in SSc patients. Mechanistically, miR-214 targeted IL-33 and blocked the IL-33/ST2 axis. BMSC-Exos delivering miR-214 inhibitor augmented proliferation, migration, and fibrotic gene expression in TGF-ß1-stimulated fibroblasts. Similarly, IL-33 induced migration, proliferation, and fibrotic gene expression in fibroblasts via ST2. In BLM-treated mice, IL-33 knockout suppressed skin fibrosis, and BMSC-Exos delivered miR-214 to suppress the IL-33/ST2 axis, thus mitigating skin fibrosis. Conclusively, BMSC-Exos alleviate skin fibrosis through the blockade of the IL-33/ST2 axis by delivering miR-214.

Biosynthesis and Detection of Domoic Acid from Diatom Pseudo-nitzschia: A Review.

The domoic acid (DA) produced by certain species of the marine pennate diatom genus Pseudo-nitzschia is highly neurotoxic and can induce nerve excitability and neurotoxicity by binding with ionotropic glutamate receptors, causing amnesic shellfish poisoning in humans who consume seafood contaminated with DA. In recent years, poisoning of humans caused by DA has occurred around the world, which has attracted increasing attention, and studies on DA production by Pseudo-nitzschia have become the hotpot. This article reviews the progress in the biosynthesis of DA by the typical diatom Pseudo-nitzschia, in which the metabolic pathway of the biosynthesis of DA and its precursors, i.e., geranyl pyrophosphate and L-glutamate, and the various environmental factors affecting DA production including temperature, light intensity, nutrients, trace metals, and alien bacteria are discussed. The detection methods of DA (including bioassays, enzyme linked immunosorbent assays, high performance liquid chromatography, capillary electrophoresis and biosensors), as well as the morphology and toxigenicity of Pseudo-nitzschia are also presented.

MiR-144-3p induced by SP1 promotes IL-1ß-induced pyroptosis in chondrocytes via PTEN/PINK1/Parkin axis.

Rheumatoid arthritis (RA) often leads to functional disabilities and deformities. MiRNA plays a vital role in cell pyroptosis. Nevertheless, the function and underlying mechanism of miR-144-3p in pyroptosis during the progression of RA remains unclear. In this study, N1511 cells were stimulated with IL-1ß to construct a RA model. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay was performed to assess the cell viability. Cell pyroptosis was detected by flow cytometry. The levels of inflammatory cytokines (TNF-α, IL-6, and IL-18) were assessed by enzyme-linked immunosorbent assay (ELISA). The relationship among specific protein 1 (SP1), microRNA-144-3p (miR-144-3p), and phosphatase and tensin homolog (PTEN) was explored by dual-luciferase reporter assay, RNA immunoprecipitation (RIP), and chromatin immunoprecipitation (ChIP), respectively. The level of miR-144-3p in N1511 cells was upregulated by IL-1ß. MiR-144-3p knockdown inhibited IL-1ß-induced pyroptosis in N1511 cells, and the expressions of NOD-like receptor family pyrin domain containing 3 (NLRP3), Cleaved caspase-1, Gasdermin D (GSDMD), and Cleaved caspase-3 in IL-1ß-stimulated N1511 cells were increased. The levels of inflammatory cytokines in N1511 cells were increased by IL-1ß, which were restored by miR-144-3p knockdown. MiR-144-3p knockdown abolished IL-1ß-induced inactivation of putative kinase 1 (PINK1)/Parkin RBR E3 ubiquitin-protein (Parkin) signalling. Moreover, transcription factor SP1 could upregulate miR-144-3p expression and miR-144-3p negatively regulated PTEN expression. In summary, MiR-144-3p induced by SP1 could promote IL-1ß-induced chondrocyte pyroptosis via inhibiting PTEN expression and suppressing the activation of PINK1/Parkin signalling, which provided a new strategy against RA.

Highly Suspected COVID-19 Cluster with Multiple Negative SARS-CoV-2 RNA Tests: A Case Report.

The patient had several close contacts with friends from Wuhan, the epicenter of the epidemic. His mother and father had close contact with him. His father was later diagnosed with COVID-19 infection after a positive reverse transcription PCR test for SARS-CoV-2 RNA. The patient and his mother were diagnosed as suspected cases of COVID-19 based on a history of exposure, clinical manifestation, and imaging examination. However, the patient was tested more than three times with the reverse transcription PCR test for SARS-CoV-2 RNA, and the results were negative each time. COVID-19 should be suspected, regardless of SARS-CoV-2 test negativity, for recent close contact with a confirmed case and respiratory symptoms.

mir-1-mediated paracrine effect of cancer-associated fibroblasts on lung cancer cell proliferation and chemoresistance.

Lung cancer is the leading cause of cancer-related mortality in humans worldwide. Moreover, the overall 5-year survival rate is only 15%. Pathologically almost 80% of all lung cancer cases are non-small cell lung cancer (NSCLC). Cancer-associated fibroblasts (CAFs) have been found to exist in a large number of NSCLCs. CAFs have been proven to promote tumor progression, metastasis and resistance to therapy through paracrine effects in most solid tumors. In the present study, firstly we isolated CAFs from patient tissues and demonstrated that they promoted cell proliferation and chemoresistance to cisplatin in the lung cancer cell lines A549 and 95D in a paracrine manner. Secondly, using ELISA and quantative PCR, we found that a higher amount of stromal cell-derived factor 1 (SDF-1) existed in the CAFs rather than that observed in the normal fibroblasts (NFs). Thirdly, we detected that SDF-1 facilitated lung cancer cell proliferation and drug resistance via the CXCR4-mediated signaling pathway which involved NF-κB and Bcl-xL. Moreover, we also confirmed that the expression level of SDF-1 in the CAFs was negatively regulated by microRNA mir-1 through microRNA overexpression and quantitative PCR. Overall, our data provide one explanation for the effects of CAFs on lung cancer cells. Meanwhile, our results also suggest CAFs as a potential therapeutic target in tumor treatment.

MUC1 gene polymorphisms are associated with serum KL-6 levels and pulmonary dysfunction in pulmonary alveolar proteinosis.

BACKGROUND: KL-6, a human MUC1 mucin, is a sensitive biomarker for interstitial lung diseases including pulmonary alveolar proteinosis (PAP). A correlation between MUC1 gene single nucleotide polymorphism (SNP) rs4072037 genotype and serum KL-6 levels has been reported. This study was aimed at investigating the correlation between MUC1 SNP genotype, severity of disease and disease outcome in PAP. METHODS: Twenty four patients with PAP and 30 healthy volunteers were studied. MUC1 rs4072037 was detected by using a real-time polymerase chain reaction (RT-PCR). Genotyping was performed by pyrosequencing. KL-6 levels were measured in serum by Nanopia KL-6 assay (SEKISUI Diagnostics). RESULTS: The frequency of MUC1 rs4072037 alleles was significantly different between PAP patients and healthy volunteers (PAP, A/A 46%, A/G 54%, G/G 0%; healthy controls, A/A 30%, A/G 40%, G/G 30%; p = 0.013). Serum KL-6 levels were significantly higher in PAP patients than in controls (p < 0.0001), and significantly higher in PAP patients with A/A genotype than in those with A/G genotype (p = 0.007). Patients with A/A genotype had higher alveolar-arterial oxygen difference (A-aDO2) and lower DLco compared to those with A/G genotype (p = 0.027 and p = 0.012, respectively). Multivariate analysis, Kaplan-Meier analysis and C statistics showed that the rs4072037 A/A genotype was associated with higher rate of disease progression (HR: 5.557, p = 0.014). CONCLUSIONS: MUC1 rs4072037 A/A genotype is associated with more severe pulmonary dysfunction and a higher rate of disease progression in PAP patients.