A novel molecular mechanism of microRNA-21 inducing pulmonary fibrosis and human pulmonary fibroblast extracellular matrix through transforming growth factor ß1-mediated SMADs activation.

Pulmonary fibrosis (PF), characterized by the destruction of lung tissue architecture and the abnormal deposition of extracellular matrix (ECM) proteins, currently has no satisfactory treatment. The role of microRNA (miR)-21 in PF has been reported; the current study attempted to investigate a novel molecular mechanism by which miR-21 exerted its function. Consistent with previous studies, miR-21 inhibition reduced ECM protein levels in bleomycin (BLM)-induced mouse model of PF. In human pulmonary fibroblast (IMR-90), miR-21 inhibition reduced transforming growth factor ß1 (TGFß1)-induced ECM protein expression. Regarding a novel molecular mechanism, TGFß1 combined with TGFß1 receptor 1 (TGFß1RI) to activate SMAD2/3, promote SMAD4 nucleus transformation, and thus regulate miR-21 expression and ECM. SMAD3 and SMADs complex could bind to the promoter region of miR-21 to promote miR-21 expression. In conclusion, miR-21 exerts promotive effects on BLM-induced PF and TGFß1-induced ECM in IMR-90; TGFß1 combines with TGFß1RI to activate SMAD2/3, promote SMAD4 nucleus transformation, promote miR-21 expression, and thus to promote BLM-induced PF and TGFß1-induced ECM in IMR-90 cells.

[Endobronchial ultrasonography with distance by thin bronchoscopy in diagnosing peripheral pulmonary lesions].

OBJECTIVE: To evaluate the efficacy, safety and factors related to diagnostic yield of transbronchial biopsy (TBB) using thin bronchoscopy to endobronchial ultrasonography with distance ( EBUS-D) for peripheral pulmonary lesions (PPLs). METHODS: Between October 2013 to September 2014, 117 patients [67 males and 50 females, aged (62.2 ± 10.9 ) years] underwent EBUS-D-guided TBB for the diagnosis of PPLs [mean size (22.9 ± 9.5) mm] and their medical records were retrospectively reviewed and analysed. EBUS was performed using a 4-mm thin bronchoscope and a 1.4 mm radial ultrasound probe. EBUS-D was to measure the distance between the PPL to the target bronchial orifice or to the outer orifice of the working channel of the bronchoscope when an EBUS image of the PPL was observed, and then the biopsy forceps were advanced to this measured distance and biopsy followed. RESULTS: The visualization yield of EBUS was 77.8% (91/117). The overall diagnostic yield was 65.0% (76/117) by EBUS-D-guided TBB, and the diagnostic yield in malignant and benign lesions was 75.0% (66/88) and 34.5% (10/29), respectively. The diagnostic yield for PPLs > 20 mm in diameter was significantly higher than that for those ≤ 20 mm in diameter (78.7%,48/61 versus 50.0%, 28/56) (χ² 10.56, P=0.001). There was no significant difference in diagnostic yield between lobar distribution (right upper lobe 61.8%, 21/34; right middle lobe 91.7%, 11/12; right lower lobe 59.1%, 13/22; left upper lobe 57.1%,12/21; lingula 80.0%,4/5; left lower lobe 65.2%,15/23) (χ² = 5.31, P=0.38). The diagnostic sensitivity was only 18.2% for lesions close to visceral pleura with mean size ≤ 20 mm. Sometimes radial probe could pass through the PPL without resistance, and the diagnostic yield was lower in this situation. Complications including bleeding and chest pain recovered spontaneously. CONCLUSION: Using EBUS-D-TBB with a thin bronchoscope, the vast majority of peripheral pulmonary lesions could be identified. The modality was far more cost-effective than EBUS-GS and there were no significant complications associated with this procedure. Lesion size, connection to the visceral pleura and radial probe through the lesion influenced the diagnostic yield.

The MIR100HG/miR-29a-3p/Tab1 axis modulates TGF-ß1-induced fibrotic changes in type II alveolar epithelial cells BLM-caused lung fibrogenesis in mice.

Transforming growth factor (TGF)-ß1-induced fibrotic changes in alveolar epithelium is a critical event in pulmonary fibrosis. Herein, we recognized that lncRNA mir-100-let-7a-2-mir-125b-1 cluster host gene (MIR100HG) was abnormally upregulated within human idiopathic pulmonary fibrosis (IPF) lung tissue, bleomycin (BLM)-caused pulmonary fibrotic model mice and TGF-ß1-stimulated mice type II alveolar epithelial cells. In vivo, MIR100HG knockdown attenuated BLM-caused lung fibrogenesis in mice; in vitro, MIR100HG knockdown attenuated TGF-ß1-induced fibrotic changes in mice type II alveolar epithelial cells. Through direct binding, MIR100HG knockdown upregulated microRNA-29a-3p (miR-29a-3p) expression; through serving as competing endogenous RNA for miR-29a-3p, MIR100HG knockdown downregulated TGF-beta activated kinase 1/MAP3K7 binding protein 1 (Tab1) expression. Finally, under TGF-ß1 stimulation, Tab1 knockdown attenuated TGF-ß1-induced fibrotic changes and partially attenuated the effects of miR-29a-3p inhibition. In conclusion, we demonstrated the aberrant upregulation of lncRNA MIR100HG in BLM-caused lung fibrogenesis and TGF-ß1-stimulated MLE 12 cells. The MIR100HG/miR-29a-3p/Tab1 axis could modulate TGF-ß1-induced fibrotic changes in type II alveolar epithelial cells and, thus, might be promising targets for pulmonary fibrosis therapy.

Comparison of radial endobronchial ultrasound-guided transbronchial lung biopsy with distance measurement versus with guide sheath in diagnosing peripheral pulmonary lesions with a diameter ≥3 cm by thin bronchoscope.

OBJECTIVE: This study aims to explore the diagnostic values of radial endobronchial ultrasound-guided transbronchial lung biopsy with distance (rEBUS-D-TBLB) measurement and with guide sheath (rEBUS-GS-TBLB) for peripheral pulmonary lesions (PPLs) with a diameter ≥3 cm by thin bronchoscope. PATIENTS AND METHODS: Six hundred and three patients with PPL (diameter ≥3 cm) were enrolled in this study. The subjects were divided into the rEBUS-D-TBLB and rEBUS-GS-TBLB groups by the random number table method. Patients were assigned to undergo rEBUS-D-TBLB or rEBUS-GS-TBLB, respectively. The histopathology, positive diagnosis rates, duration of the procedure, and postoperative adverse effects between the two groups were examined. RESULTS: A total of 569 patients were included in this study according to the inclusion and exclusion criteria, with 282 cases in the rEBUS-D-TBLB group and 287 cases in the rEBUS-GS-TBLB group. For malignant diseases, the positive diagnosis rates of PPL in the outer/inner-middle lung bands and the right-upper/-lower lung lobes by rEBUS-D-TBLB were noninferior to those of rEBUS-GS-TBLB. The duration of the procedure of rEBUS-D-TBLB was longer than that of rEBUS-GS-TBLB. There were 14 cases of hemorrhage >50 mL, 1 case of postoperative chest pain in the rEBUS-D-TBLB group, and 3 cases of hemorrhage >50 mL in the rEBUS-GS-TBLB group. CONCLUSION: REBUS-D-TBLB by thin bronchoscope has a high diagnostic value for PPL with a diameter ≥3 cm, which may be considered a useful alternative for rEBUS-GS-TBLB in the clinic.

Dexmedetomidine combined with midazolam infusion guided by bispectral index during bronchoscopy.

BACKGROUND: Conscious sedation guided by bispectral index (BIS) during bronchoscopy has been proved to be a feasible approach. This study aimed to investigate the safety and efficacy of dexmedetomidine combined with midazolam for undergoing conscious sedation during bronchoscopy. METHODS: The trial was registered prior to patient enrollment at the Chinese Clinical Trial Registry. Patients were randomized into DEX group (dexmedetomidine combined with midazolam) and FEN group (fentanyl combined with midazolam). Bronchoscopy was performed under awake sedation titrated to a BIS level of 60-80. The primary endpoint was the incidence of hypoxia, the secondary endpoint was the incidence of bradycardia and hypotension, effect of sedation including satisfaction degree (VAS) of the operators and patients and patients' willingness to undergo bronchoscopy again. RESULTS: A total of 222 cases in DEX group and 211 cases in FEN group completed the study. The incidence of hypoxia and tachycardia in DEX group was lower than that in FEN group (8.1% vs 14.7%, 10.4% vs 19.0%, p < 0.05), and the incidence of hypotension and bradycardia in DEX group was higher than that in FEN group (6.8% vs 0, 15.3% vs 8.1%, p < 0.05). Midazolam dosage was significantly lower in the DEX group than in the FEN group, and the duration of surgery was significantly longer in the DEX group. The differences in intraoperative discomfort of VAS score, satisfaction VAS score, and willingness rate to undergo bronchoscopy again were not statistically significant between the two groups. In addition, the proportion of "procedural interference by patient movement" in DEX group was higher than that in FEN group. CONCLUSIONS: The conscious sedation regimen of dexmedetomidine combined with midazolam monitored by BIS is considered to be safe and effective during bronchoscopy. The occurrence of hypoxia and tachycardia was less, and the fluctuation of blood pressure and heart rate was mild, but the proportion of bradycardia in dexmedetomidine group was higher than that in fentanyl combined with midazolam group.

TGF­ß1 induces CREB1­mediated miR­1290 upregulation to antagonize lung fibrosis via Napsin A.

The pathologic mechanisms of pulmonary fibrosis (PF), one of the most common chronic pulmonary diseases, remain unclear. Napsin A is an aspartic proteinase that has been regarded as a hallmark of pulmonary adenocarcinoma. The present study aimed to investigate the specific function and molecular mechanisms of Napsin A in PF from the perspective of microRNA (miRNA or miR) regulation. In the present study, it was found that miR­1290 downregulated the expression of Napsin A by binding to its 3'­UTR. Cell viability was examined by MTT assay. The protein levels of α­smooth muscle actin (α­SMA), Collagen I and Napsin A were examined by western blot analysis. The predicted targeting of Napsin A by miR­1290 was validated by luciferase reporter assay. The protein content of α­SMA was examined by immunofluorescence staining. miR­1290 was found to be upregulated in blood samples from patients with PF and in TGF­ß1­stimulated A549 cells. miR­1290 was found to directly target Napsin A. miR­1290 overexpression also significantly promoted A549 cell proliferation and increased the protein levels of markers of fibrosis. Napsin A knockdown exerted effects on A549 cell proliferation and TGF­ß1­induced fibrosis that were similar to those induced by miR­1290 overexpression; more importantly, Napsin A knockdown significantly reversed the effects of miR­1290 inhibition, indicating that miR­1290 promotes TGF­ß1­induced fibrosis by targeting Napsin A. Moreover, TGF­ß1­induced CAMP responsive element binding protein 1 (CREB1) overexpression promoted the transcription of miR­1290 in A549 cells. On the whole, the findings of the present study demonstrate that TGF­ß1­induced CREB1 overexpression induces the significant upregulation of miR­1290 expression, thus aggravating TGF­ß1­induced fibrotic changes in A549 cells via the miR­1290 downstream target, Napsin A.

Analysis of indications for pulmonary peripheral lesions diagnosed using radial endobronchial ultrasound-guided transbronchial lung biopsy.

The aim of the present study was to determine the indications for radial endobronchial ultrasound-guided transbronchial lung biopsy (rEBUS-D-TBLB) for the diagnosis of peripheral pulmonary lesions (PPL) located at the bronchopulmonary segments and subsegments. Data collected from 774 patients who underwent rEBUS-D-TBLB for suspected PPL, including clinical information, distribution of lesions, diagnostic spectrum and diagnostic rate, were collected and retrospectively reviewed. Additionally, the Wilcoxon signed-rank test was performed to analyze the diagnostic yield of lesions in bronchopulmonary subsegments under the lesion diameter limit of 3 cm. In total, 802 lesions were found in 774 patients. The diagnostic yield of rEBUS-D-TBLB for all lesions was 67.18%. Overall, 362 cases of malignant disease and 158 cases of benign disease were diagnosed, with sensitivities of 70.98 and 79.00% respectively. Lesions were distributed throughout the 18 bronchopulmonary segments of the lungs. The bronchopulmonary segments with >5% of the majority of the discovered lesions were LB1+2, LB3, LB6, LB10, RB1-4 and RB9. The diagnostic yield of rEBUS-D-TBLB was found to be >65% for lesions located at LB3, RB1-3 and RB9. Further rEBUS-D-TBLB examinations of the LB1+2a, LB6a and RB4b segments produced diagnostic yields of 81.25, 66.67 and 71.43% respectively. Finally, at segment RB4a, rEBUS-D-TBLB examination was more effective for lesions with diameters >3 cm compared with lesions with diameters <3 cm. The diagnostic yields for PPL distributed at LB1+2a, LB3, LB6a, RB1-3, RB4a (diameter >3 cm), RB4b, and RB9 using rEBUS-D-TBLB were higher compared with for other segments, providing a theoretical basis for the clinical application of rEBUS-D-TBLB for the diagnosis of PPL in patients.

MicroRNA­4500 suppresses tumor progression in non­small cell lung cancer by regulating STAT3.

Research has revealed that microRNA (miR)­4500 is downregulated in non­small cell lung cancer (NSCLC), and miR­4500 suppresses tumor growth by targeting lin­28 homolog B and NRAS proto­oncogene, GTPase. In the present study, it was reported that signal transducer and activator of transcription 3 (STAT3) may function as a novel target gene for miR­4500 in NSCLC. The experiments conducted in the present study confirmed that the miR­4500 expression was decreased in NSCLC tissues and cells compared with adjacent normal tissues and a normal lung cell line. miR­4500 suppressed the cell proliferation, migration, invasion and promoted apoptosis of the human NSCLC cell lines A549 and H1975. Expression of STAT3 was negatively correlated with miR­4500 expression in vivo. A luciferase reporter assay suggested that miR­4500 directly targeted the 3' untranslated region of STAT3. The tumor inhibition effect of small interfering RNA STAT3 in A549 and H1975 lines may be partially impaired by a miR­4500 inhibitor. The results of the present study suggests that miR­4500 may be a tumor suppressor and a potential therapeutic target in NSCLC.

Upregulated microRNA­671­3p promotes tumor progression by suppressing forkhead box P2 expression in non­small­cell lung cancer.

In the present study, the expression of microRNA (miR)­671­3p in non­small­cell lung cancer (NSCLC) was detected via reverse transcription­quantitative polymerase chain reaction analysis, and its role in cell proliferation, apoptosis, migration and invasion was investigated via Cell Counting Kit­8, colony formation, flow cytometry, Transwell and scratch assays, respectively. It was observed that the expression of miR­671­3p was upregulated in NSCLC tissues and cell lines (A549 and H1975). Treatment with miR­671­3p inhibitors suppressed cell proliferation, migration and invasion, and increased apoptosis in vitro, suggesting that miR­671­3p functions as an oncogene in NSCLC. In addition, forkhead box P2 (FOXP2) has been reported to be a tumor suppressor that is downregulated in several types of cancer, and its low expression was confirmed in NSCLC tissues and cell lines in the current study via western blotting. The results of the luciferase reporter assay also demonstrated that miR­671­3p targeted directly the 3'­untranslated region of FOXP2. Furthermore, overexpression of FOXP2 in A549 and H1975 cell lines suppressed the growth, migration and invasion, and promoted apoptosis, whereas these effects were reversed by transfection with miR­671­3p mimics, suggesting that miR­671­3p promoted tumor progression via regulating FOXP2. Taken together, the results reported in the present study implied that miR­671­3p may be a potential therapeutic target in NSCLC.

Radial endobronchial ultrasonography with distance measurement through a thin bronchoscope for the diagnosis of malignant peripheral pulmonary lesions.

BACKGROUND: Peripheral pulmonary lesions (PPLs) are being discovered more frequently. We investigated efficiency, safety, and influencing factors in radial probe endobronchial ultrasound with distance measurement (rEBUS-D) using a thin bronchoscope during transbronchial biopsy (TBB) for the diagnosis of malignant PPLs. METHODS: Patients with PPLs who underwent rEBUS were retrospectively analyzed. Cases with rEBUS-D and a gold-standard final diagnosis were considered. RESULTS: rEBUS was completed in 589 cases; 328 were analyzed. The lesion discovery rate was 85.06%; the overall rEBUS-D-TBB diagnostic rate was 54.88%. There were 193 cases of malignant tumors. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of rEBUS-D-TBB in the diagnosis of malignant PPLs were 63.73%, 100%, 100%, 65.85%, and 78.40%, respectively. Single- and multi-factor analyses showed that lesion size, ultrasound probe position, and a positive bronchus sign on thoracic computed tomography (CT) were significant factors influencing diagnosis (all P=0.000); probe position and the bronchus sign were independent influencing factors. The effect of lesion distribution on diagnosis was not significant. In seven cases, postoperative pathology showed mixed tumors. Two cases of malignant tumors were combined with benign pathology; rEBUS-D-TBB did not suggest two pathologies. Thirteen cases had 50-100 mL of blood loss (3.96%); no pneumothorax or infection was observed. CONCLUSIONS: rEBUS-D-TBB had high sensitivity, 100% specificity, excellent safety, and a lower cost than rEBUS-GS-TBB in the diagnosis of malignant PPLs. Larger lesions, a positive bronchus sign on CT, and ultrasound probe position at the lesion's center yielded higher diagnostic rates.

Value of radial probe endobronchial ultrasound-guided transbronchial biopsy and computer tomography-guided transthoracic needle aspiration in the diagnosis of peripheral pulmonary lesions.

Computer tomography-guided transthoracic needle aspiration (CT-TTNA) is a minimally invasive technique for sampling peripheral lung lesions. Radial endobronchial ultrasound-guided transbronchial biopsy (rEBUS-TBB) is an alternative. The present study analyzed and compared rEBUS-TBB and CT-TTNA in the diagnosis of peripheral pulmonary lesions (PPL).Clinical data of 513 patients with PPL who underwent an rEBUS-TBB or CT-TTNA examination were analyzed retrospectively. The positive diagnostic rate, complication rate, and influencing factors of the 2 methods were compared.The positive diagnostic rate and complication rate were significantly higher in CT-TTNA than rEBUS-TBB (P = .001; P < .001, respectively). The rEBUS-TBB group showed a higher positive diagnostic rate in larger lesions (>2 cm) than in smaller (≤2 cm) (P = .012), and was lower in the lesions proximal to the chest wall than those distally located (P = .046); no significant difference was observed in the different pulmonary segments (P = .109). In the CT-TTNA group, the positive diagnostic rate in larger lesions did not differ significantly than the smaller lesions (P = .05); it differed significantly in different segments (P = .044). The incidence of pneumothorax was lower in lesions proximal to the chest wall than those located distally (P = .037). In the rEBUS-TBB group, the success rate of the exploration and biopsy of the lesions was 87.4%; the rate of exploration of larger lesions and with bronchial sign was higher than smaller lesions and without bronchial sign (P < .001; P < .001, respectively) while that of lesions close to the chest wall was lower than those distally located (P = .006).rEBUS-TBB and CT-TTNA are effective and safe in the diagnosis of PPL. The positive diagnostic rate of CT-TTNA is higher than rEBUS-TBB. The incidence of pneumothorax in CT-TTNA is higher than rEBUS-TBB. CT-TTNA is selected for smaller lesions close to the chest wall; rEBUS-TBB is used for lesions larger, distal from the chest wall or with a bronchial sign.

Comparison of radial endobronchial ultrasound with a guide sheath and with distance by thin bronchoscopy for the diagnosis of peripheral pulmonary lesions: a prospective randomized crossover trial.

BACKGROUND: Transbronchial biopsy (TBB) using radial endobronchial ultrasound with a guide sheath (REBUS-GS) has improved the diagnosis of peripheral pulmonary lesions (PPLs). Because of the high cost of the GS, REBUS with distance (REBUS-D) has certain advantages. The aim of this study was to compare the diagnostic yield of the REBUS-GS and REBUS-D by thin bronchoscopy for PPLs. METHODS: Patients with PPLs were enrolled in a prospective randomized crossover study from August 2014 and July 2015. Once the lesion was localized, TBB using REBUS-GS and TBB using REBUS-D were performed sequentially in a randomized order in each patient. Each patient received four to five transbronchial biopsies with REBUS-GS as well as four to five transbronchial biopsies with REBUS-D. All brushing was performed through GS. RESULTS: A total of 54 patients were enrolled in this study. After excluding seven participants with PPLs that were not detected by REBUS, a total of 47 subjects underwent REBUS-TBB. The diagnostic yield of REBUS-GS-TBB and REBUS-D-TBB was 72.2% (39/54) and 75.9% (41/54) respectively (P=0.625). Moreover, there was no statistically significant difference in diagnostic yield between REBUS-GS and REBUS-D in different lobe lesions and lesion sizes. Two cases of adenocarcinoma were only diagnosed with REBUS-GS-TBB. Two cases of tuberculosis, one case of mucosa-associated lymphoid tissue lymphoma (MALT) and one case of adenocarcinoma were only diagnosed by REBUS-D-TBB. The mean biopsy time after visualization of PPLs for REBUS-GS-TBB and REBUS-D-TBB were 5.17±2.34 and 7.36±3.18 min (P=0.00053). CONCLUSIONS: Using thin bronchoscopy, the diagnostic yield for PPLs with REBUS-D-TBB is not inferior to the yield with REBUS-GS-TBB. The diagnosis rate of small subpleural lesions with REBUS-D is lower than the rate with REBUS-GS. Although it is associated with shorter operation time and less bleeding, REBUS-GS has a higher cost and sometimes leads to check failure due to small specimens and the impact of the bronchoscope curvature.