Expression and clinical significance of lung-specific X protein mRNA in bronchial brushing specimens from patients with or without lung cancer

Expression and Significance of HPV16 E6/E7 mRNAs in the Bronchial Brush and TBNA Cells of Patients With Small Cell Lung Cancer

BACKGROUND AND OBJECTIVE

Small cell lung cancer (SCLC) is characterized by rapid growth, strong invasion, and early metastasis. However, the cause of its occurrence remains unclear. High-risk HPV infection is closely related to the occurrence of non-small cell lung cancer and cervical small cell neuroendocrine carcinoma.

METHODS

The expression levels of E6 mRNA and E7 mRNA in HPV16 were detected by qRT-PCR in the bronchial brushing and transbronchial needle aspiration (TBNA) of 310 patients with lung cancer and with benign lung diseases. To make the design of this experiment scientific and reasonable, the expression levels in lung squamous cell carcinoma were taken as positive controls, while those in benign cells were taken as negative controls.

RESULTS

The expression levels of E6 mRNA and E7 mRNA in SCLC group were significantly higher than those in benign cell group and slight higher than those in squamous cell carcinoma group. The expression levels of E6 mRNA and E7 mRNA in the central type of SCLC were significantly higher than those in the peripheral type of SCLC.

CONCLUSIONS

We speculate that the occurrence of some small cell carcinoma is the same as that of some squamous cell carcinoma, which is closely related to HPV16 infection. The overexpression of E6 mRNA and E7 mRNA is in some benign lesion cells, which may be related to HPV transient infection.

Evaluation of the diagnostic accuracy of bronchial brushing cytology in lung cancer: A meta-analysis

BACKGROUND

Flexible bronchoscopy is commonly used to examine patients suspected to have lung cancer. Bronchial brushing is one of the cytological technologies for lung specimens obtained through a bronchoscope. However, the accuracy of bronchial brushing cytology (BBC) for lung cancer diagnosis is still inconclusive. The aim of this study was to evaluate the diagnostic accuracy of BBC.

METHODS

A literature search was conducted with PubMed, Embase, the Cochrane Library, Web of Science, Biomed Central, Clinical Key, and ClinicalTrials.gov. Studies that assessed the efficacy of BBC in detecting lung cancer were included. Articles that estimated the accuracy on a per-patient basis were included. Review articles, case reports, and research that provided insufficient data to construct a 2 × 2 table were excluded. Both prospective trials and retrospective studies were included. English language studies were reviewed. Data synthesis was performed with a random-effects model.

RESULTS

Seventeen studies with 2538 patients were included in the study. The meta-analysis for BBC generated a pooled sensitivity of 0.67 (95% confidence interval [CI], 0.65-0.70) and a pooled specificity of 0.91 (95% CI, 0.89-0.93). The pooled diagnostic odds ratio for BBC was 24.55 (95% CI, 12.39-48.66). The subgroup analysis for studies using liquid-based cytology (LBC) generated a pooled sensitivity of 0.68 and a pooled specificity of 0.92. The pooled diagnostic odds ratio of studies using LBC was 114.18.

CONCLUSIONS

These findings indicate that BBC is a discriminative diagnostic approach with moderate sensitivity and high specificity for diagnosing peripheral pulmonary lesions. BBC using LBC has higher diagnostic performance.

HPV16 E6/E7 upregulate hTERC mRNA and gene amplification levels by relieving the effect of LKB1 on Sp1 phosphorylation in lung cancer cells

Background:

There is an immediate need for research on the mechanism underlying telomerase activation and overexpression.

Materials & Methods:

A total of 174 patients with lung cancer (n = 106) and benign lung disease (n = 68) were recruited for the current study. The mRNA expression levels of E6, E7, LKB1, Sp1, and hTERC in brushing cells were detected by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), and hTERC amplification was also detected by fluorescence in situ hybridization (FISH). To investigate the potential mechanism, bidirectional genetic manipulation was performed in well-established lung cancer cell lines.

Results:

Our results indicated that the mRNA expression levels of E6, E7, Sp1, and hTERC and the amplification level of hTERC were significantly increased in the malignant group compared with those of the benign group (p < 0.01). Conversely, the mRNA expression level of LKB1 was significantly decreased in the malignant group (p < 0.01). The correlation between E6, E7, Sp1, and hTERC expression was positive but was negative with LKB1 (p < 0.01). Our results also showed that HPV16 E6/E7 downregulated the expression of LKB1 at both the protein and mRNA levels. The loss of LKB1 upregulated Sp1 expression, and also promoted Sp1 activity. Sp1 further upregulated hTERC at the mRNA and gene amplification levels. Thus, we proposed a HPV–LKB1–Sp1–hTERC axis of E6/E7 upregulation of hTERC expression.

Conclusion:

We demonstrated for the first time that E6 and E7 promoted hTERC mRNA expression and the amplification of hTERC by relieving the effect of LKB1 on the phosphorylation of Sp1. Sp1 further activated hTERC by directly binding to the promoter regions of hTERC.

Long-term persistent infection of HPV 16 E6 up-regulate SP1 and hTERT by inhibiting LKB1 in lung cancer cells

HPV 16 E6 upregulates hTERT expression in lung cancer cells. However, the underlying molecular mechanism is unclear. In this paper, E6, LKB1, SP1, and hTERT mRNA expression levels were detected in brushing cells of patients with lung cancer (n = 106) and with benign lung disease (n = 68) by qRT-PCR. The mRNA expression levels of E6, SP1, and hTERT were significantly increased in the malignant group compared with the benign group (P < 0.01). Conversely, the mRNA expression level of LKB1 was significantly decreased in the malignant group (P < 0.01). Furthermore, the correlation between E6, Sp1, hTERT, and LKB1 was performed, our results indicated that E6, Sp1, and hTERT with positive, but LKB1 with negative correlation (P < 0.01). To investigate the potential relationship between these genes, using double directional genetic manipulation, we showed that overexpression of E6 in H1299 cells down-regulated LKB1 mRNA and protein expression but up-regulated SP1 and hTERT as well as the transcriptional activity of Sp1. In contrast, knockdown of E6 in A549 cells by short-interference RNAs (siRNAs) up-regulated LKB1 expression, but down-regulated SP1 and hTERT expression as well as Sp1 activity. LKB1 loss upregulated both SP1 and hTERT at the protein and mRNA level as well as SP1 activity. To verify that the role of E6 on hTERT was mediated by SP1, siRNA knockdown of SP1 was performed on both H1299 and A549 cell lines. Inhibition of SP1 downregulated hTERT expression. Our results indicate that HPV16 E6 indirectly upregulated the expression of hTERT by inhibition of LBK1 expression and upregulation of Sp1 expression, thus suggesting a HPV-LKB1-SP1-hTERT axis for the tumorigenesis of lung cancer. Our study also provides new evidence to support the critical role of SP1 and LKB1 in the pathogenesis of HPV-related lung cancer, and suggests novel therapeutic targets.

SPLUNC1 Is a Significant Marker in Pleural Effusion from Lung Cancer Compared to Tuberculosis

SPLUNC1 (Short palate, lung and nasal epithelium clone1) protein is an abundant secretory product of epithelia present throughout the conducting airways. Although its function is still not fully known, most studies have focused on its defensive effect in the infection of human airways and its potential to serve as a molecular marker for lung cancer. In this study, we further evaluated the SPLUNC1 expression in patients with lung disease to explore its role in cancer or tuberculosis at the protein level. We generated a panel of antibodies by using protein from a eukaryotic expression system as the immunogen to mice. It was the panel of SPLUNC1 monoclonal antibodies that allowed us to comparatively determine SPLUNC1 protein in lung cancer and tuberculosis infection by detecting sera and pleural effusion other than airway surface. The results showed that the SPLUNC1 level was not significantly changed either from sera of lung cancer or control. There was a significant increase in pleural effusion from lung cancer when compared to tuberculosis. These results indicate that SPLUNC1 may be a useful marker for tracing lung cancer cells, based on its epithelial origin property in pleural effusion.

Diagnostic utility of LUNX mRNA and VEGF mRNA in pleural fluid for differentiating benign from malignant origin

OBJECTIVE

The purpose of this study was to evaluate the diagnostic utility of lung-specific X protein (LUNX) mRNA and vascular endothelial growth factor mRNA in differentiating pleural effusion of different origin.

METHODS

A total of 136 patients with pleural effusion (46 cases of malignant pleural effusion caused by lung cancer, 30 cases of malignant pleural effusion caused by other cancers and 60 cases of benign pleural effusion) were enrolled in this study. Levels of LUNX mRNA and vascular endothelial growth factor mRNA in pleural fluid were detected by real-time quantitative polymerase chain reaction. Pleural fluid carcinoembryonic antigen and Cyfra21-1 were also measured simultaneously.

RESULTS

The LUNX mRNA level was significantly higher in malignant pleural effusion caused by lung cancer than in malignant pleural effusion caused by other cancers and in benign pleural effusion. In malignant pleural effusion caused by cancers of different origin, the vascular endothelial growth factor mRNA level was significantly higher than in benign pleural effusion. For the diagnosis of malignant pleural effusion caused by lung cancer, LUNX mRNA exhibited higher sensitivity (80%), when compared with vascular endothelial growth factor mRNA (65%), carcinoembryonic antigen (67%) and Cyfra21-1 (61%), with the same specificity (95%). The combination of LUNX mRNA and cytology achieved a sensitivity of 85%. The combined use of LUNX mRNA and vascular endothelial growth factor mRNA and cytology raised the sensitivity to 89%, with 95% specificity. In initial cytology-negative pleural effusion from lung cancer, LUNX mRNA achieved the highest positive result (65%) among the four markers.

CONCLUSIONS

The detection of LUNX mRNA and vascular endothelial growth factor mRNA in pleural fluid may be a complementary tool for the diagnosis of malignant pleural effusion. In particular, pleural fluid LUNX mRNA provided a valuable adjunct in distinguishing malignant pleural effusion caused by lung cancer from benign pleural effusion.

Diagnostic utility of VEGF mRNA and SP1 mRNA expression in bronchial cells of patients with lung cancer

BACKGROUND AND OBJECTIVE

Bronchial brushing is important for cytological diagnosis of lung carcinoma; however, cytological evaluation alone remains relatively insensitive. The aim of this study was to assess the diagnostic utility of vascular endothelial growth factor (VEGF) messenger ribonucleic acid (mRNA) and specificity protein 1 (SP1) mRNA in bronchial brushings in patients with or without lung cancer.

METHODS

VEGF mRNA and SP1 mRNA were measured in liquid-based cells from bronchial brushings in patients with verified lung cancer (n = 93) and with benign lung disease that included tuberculosis (n = 51). This was done using the reverse-transcription polymerase chain reaction.

RESULTS

Both VEGF mRNA and SP1 mRNA were significantly more likely to be expressed in the cancer group than in the control (benign) group, whatever their cell type. It was also more often found in the tuberculosis group than in the inflammation group (P < 0.01). In the cancer group, VEGF mRNA was significantly correlated with SP1 mRNA (P < 0.01). Of the 36 false negative cytology results, 30 gave positive results for VEGF mRNA and 34 for SP1 mRNA. The four false positive VEGF results were all diagnosed as tuberculosis. VEGF mRNA gave the highest diagnostic performance with serial use: sensitivity 89.2% and accuracy 90.3%. This was significantly better than cytology (P < 0.01).

CONCLUSIONS

Detection of VEGF mRNA and SP1 mRNA in bronchial brushing cells may be used as an ancillary tool to cytological diagnosis for detection of early-stage lung cancer. It may also help distinguish tuberculosis from other causes of lung inflammation.

Significance of combined detection of LunX mRNA and tumor markers in diagnosis of lung carcinoma

OBJECTIVE

To evaluate the significance of combined detection of LunX mRNA, carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and cytokeratin 21-1 fragment (CYFRA21-1) in clinical diagnosis of lung carcinoma.

METHODS

Based on the quantitative RT-PCR and chemiluminescence immunoassay, the expression levels of LunX mRNA, CEA, NSE, and CYFRA21-1 in 113 patients with lung carcinoma (case group) and 30 healthy participants (control group) were detected. Meantime, the sensitivity, specificity, and accuracy of the combination detection were also explored.

RESULTS

The positive rates of LunX mRNA in peripheral blood and CEA, NSE, and CYFRA21-1 in serum were significantly higher in case group than those in control group ((χ) (2)=17.295, 16.825, 19.148, and 17.450; P<0.05). There was no statistical significance when positive rate of LunX mRNA was evaluated among different pathological types ((χ) (2)=0.047, P>0.05). The positive rate of LunX mRNA in stage I + II, III, and IV had a significantly increasing tendency ((χ) (2)=10.565, 32.462, P<0.05). The positive rate of CYFRA21-1 was highest in squamous carcinoma (78.5%), the positive rate of NSE was highest in small cell carcinoma (86.7%), and the positive rate of CEA wag highest in lung adenocarcinoma (80.4%). The sensitivity and accuracy of the combination detection were 91.1% and 88.1%, respectively.

CONCLUSIONS

The combined detection of LunX mRNA and tumor markers (TMs) including CEA, NSE, and CYFRA21-1 in peripheral blood is helpful to increase the diagnostic accuracy of lung cancer. Also, it can inform the pathological typing of lung carcinoma.

The implementation of liquid-based cytology for lung and pleural-based diseases

OBJECTIVE

First introduced for the processing of cervico-vaginal samples, liquid-based cytology (LBC) soon found application in nongynecological specimens, including bronchoscopic brushings, washings and transcutaneous and transbronchial aspiration biopsy of the lung as well as pleural effusions. This article reviews the existing literature related to these specimens along with the authors' own experience.

STUDY DESIGN

A literature review was conducted through Ovid MEDLINE and PubMed search engines using several key words.

RESULTS

Most of the literature is based on data collected through the use of split samples. The data confirms that the use of LBC is an acceptable, and sometimes superior, alternative to the conventional preparations (CP). LBC offers several advantages, including the ability to transport in a stable collecting media, elimination of obscuring elements, ease of screening, excellent preservation, random representative sample, and application of ancillary techniques on additional preparations. Some diagnostic pitfalls related to the introduced artifacts were reported.

CONCLUSION

The utilization of LBC offers many advantages over CP and has a diagnostic accuracy that is equal to or surpasses that of CP. LBC affords a bridge to the future application of molecular and other ancillary techniques to cytology. Knowledge of the morphological artifacts is useful at the early stages of implementation.

Transcription expression and clinical significance of mRNA of vascular endothelial growth factor and endostatin in liquid-based preparation specimens from patients with cervical dysplasia and carcinoma

OBJECTIVES

The aim of this study was to assess the diagnostic usefulness of vascular endothelial growth factor (VEGF) and endostatin mRNA in cervical specimens of patients with cervical dysplasia and carcinoma.

STUDY DESIGN

Transcription levels of VEGF and endostatin were detected by RT-PCR in cervical liquid-based preparation specimens and compared with cytological assessments.

RESULTS

VEGF as well as endostatin mRNA expression was significantly associated with either cytological or histological diagnosis (p < 0.05). VEGF mRNA and endostatin mRNA were significantly more likely to be expressed in squamous cell carcinomas (SCC) than in cervical intraepithelial neoplasia (CIN) III (p < 0.01 and p < 0.05), and obviously also more likely to be expressed in CINII than in CINI and in CINIII than in CINII (p < 0.05). Eleven inflammation lesions gave positive results by cytology but negative results by RT-PCR for VEGF and endostatin mRNA. Twenty-four SCC lesions gave false-negative or precancerous lesion results by cytology but positive results by RT-PCR for VEGF and/or endostatin mRNA expression.

CONCLUSION

Transcription levels of VEGF and endostatin by RT-PCR may be an adjunct to cytology screening for early detection of cervical carcinomas and may determine the progressive potentiality of individual lesions, especially in high-risk patients.

Superiority and clinical significance of Lunx mRNA in the diagnosis of malignant pleural effusion caused by pulmonary carcinoma

Background

Pulmonary carcinoma is the main cause of malignant pleural effusions (MPEs). However, there is no satisfactory marker for diagnosing MPEs caused by pulmonary carcinoma. The purpose of this study is to assess the clinical significance of Lunx mRNA detection in diagnosing MPEs caused by pulmonary carcinoma.

Methods

A total of 209 patients with pleural effusions were recruited. The patients were diagnosed by cast-off cells, bronchoscopy, and pleural biopsy. The levels of Lunx mRNA in the pleural effusions were determined by real-time PCR. The levels of PH, LDH, glucose, albumin, and CEA were also determined. Patients who accepted chemotherapy underwent Lunx mRNA detection before and after the first chemotherapy session. The patients were divided into four groups according the effect of chemotherapy: complete remission (CR), partial remission (PR), no change (NC), and progressive disease (PD). The patients were also divided into two groups according the change in direction of Lunx mRNA expression after chemotherapy: increased group and decreased group. The patients were followed up to determine survival.

Results

Lunx mRNA was positive in 89 of 106 patients with pleural effusions caused by pulmonary carcinoma. The specificity and sensitivity were 95.9% and 84.9%. The area under the ROC curve was 0.922. Lunx mRNA detection was better than detection using cast-off cells and CEA. All of the Lunx-positive patients with MPEs were diagnosed with pulmonary carcinoma, and all extrapulmonary carcinoma patients were Lunx-negative. The positive predictive value of Lunx mRNA for the source of tumor cells was 100%. Lunx mRNA expression decreased after the first session of chemotherapy in the CR and PR groups, increased in the PD group, there was no change in the NC group. Further analysis indicated the change in direction of Lunx mRNA expression was associated with the overall survival of patients. The patients in the increased group had longer overall survival times than those in the decreased group.

Conclusion

Lunx mRNA is a specific tumor gene that is highly expressed in MPEs caused by pulmonary carcinoma. The changes in Lunx mRNA levels after chemotherapy can predict the prognosis of patients with MPEs caused by pulmonary carcinoma.