Different micro-RNA expression profiles distinguish subtypes of neuroendocrine tumors of the lung: results of a profiling study

MicroRNAs (miRNAs) are a class of small (∼22 nucleotides), non-coding, highly conserved single-stranded RNAs with posttranscriptional regulatory features, including the regulation of cell proliferation, differentiation, survival, and apoptosis. They are deregulated in a broad variety of tumors showing characteristic expression patterns and can, thus, be used as a diagnostic tool. In contrast to non-small cell carcinoma of the lung neuroendocrine lung tumors, encompassing typical and atypical carcinoids, small cell lung cancer and large cell neuroendocrine lung cancer, no data about deregulation of tumor entity-specific miRNAs are available to date. miRNA expression differences might give useful information about the biological characteristics of these tumors, as well as serve as helpful markers.In 12 pulmonary neuroendocrine tumors classified as either typical carcinoid, atypical, large cell neuroendocrine or small cell lung cancer, screening for 763 miRNAs known to be involved in pulmonary cancerogenesis was conducted by performing 384-well TaqMan low-density array real-time qPCR. In the entire cohort, 44 miRNAs were identified, which showed a significantly different miRNA expression. For 12 miRNAs, the difference was highly significant (P<0.01). Eight miRNAs showed a negative (miR-22, miR-29a, miR-29b, miR-29c, miR-367*; miR-504, miR-513C, miR-1200) and four miRNAs a positive (miR-18a, miR-15b*, miR-335*, miR-1201) correlation to the grade of tumor biology. The miRNAs let-7d; miR-19; miR-576-5p; miR-340*; miR-1286 are significantly associated with survival. Members of the miR-29 family seem to be extremely important in this group of tumors. We found a number of miRNAs, which showed a highly significant deregulation in pulmonary neuroendocrine tumors. Moreover, some of these deregulated miRNAs seem to allow discrimination of the various subtypes of pulmonary neuroendocrine tumors. Thus, the analysis of specific sets of miRNAs can be proposed as diagnostic and/or predictive markers in this group of neoplasias.

Efficient utilization of EBUS-TBNA samples for both diagnosis and molecular analyses

BACKGROUND

The assessment of an increasing number of molecular markers is becoming a standard requirement from endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) specimens. However, it is unclear how many needle passes should be performed and the amount of lung cancer cells that should be sent for molecular analyses. The objective of this study was to determine if it is feasible to divide the material obtained by EBUS-TBNA to allow for molecular analysis without compromising the accuracy of mediastinal staging.

OBJECTIVE

We aimed to determine if dividing EBUS-TBNA specimens has a negative impact on either histopathological diagnosis or molecular analysis.

METHODS

EBUS-TBNA was performed in 249 enlarged lymph nodes. Negative or ambiguous histopathological results were confirmed by surgical means and clinical follow-up over 6 months. The tissue obtained by EBUS-TBNA was placed onto a glass slide and divided for histopathological workup and molecular analysis. The number of passes was recorded. Both the accuracy of the mediastinal lymph node staging and the applicability of the sample division for molecular analysis were assessed.

RESULTS

Each lymph node was punctured an average of 3.18 times and division of the obtained material for diagnosis and molecular analysis was feasible in all cases. The sensitivity and accuracy of the mediastinal lymph node staging were 96.6% and 97.6%, respectively. A cytokeratin (CK)-19-mRNA concentration-based molecular test was feasible in 74.1% of cases.

CONCLUSION

Dividing EBUS-TBNA samples for both histopathological diagnosis and molecular testing is feasible and does not compromise the accuracy of mediastinal staging. This method may be an alternative to taking additional needle passes for molecular analyses.

Surgery of primary lung cancer with oligometastatic m1b synchronous single brain metastasis: analysis of 37 cases

BACKGROUND

At the time of diagnosis, lung cancer has often metastasized already. Brain metastases, however, are associated with a poor prognosis (median survival of less than 1 year). We evaluated the changes of the median survival after resection of the cerebral metastases and primary non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Between January 1999 and December 2009, 37 patients (22 men, 15 women; median age: 55.64 years; age range: 38-72 years) underwent surgery for primary NSCLC after craniotomy and removal of the synchronous single brain metastasis. The overall survival was evaluated and risk factors identified.

RESULTS

Mediastinal lymph node involvement was excluded with mediastinoscopy in 26 of the 37 patients. Postoperative N-stage was N0, N1, and N2 in 16 (43%), 10 (27%), and 11 (30%) patients, respectively. Histology was squamous cell carcinoma in 10 (27%), adenocarcinoma in 20 (54%), and large cell carcinoma in 7 (19%). The employed type of resection was anatomical segmentectomy in 6 and lobectomy in 31 patients. The 30-day mortality was 0% and postoperative complications occurred in 12 patients only (32%). The overall 1 and 2 years survival were 62 and 24%, respectively. None of the factors age, sex, tumor histology, primary location of the tumor, type of resection, adjuvant chemotherapy, or nodal status affected survival in the univariate analysis.

CONCLUSIONS

The oncologic lung resection of NSCLC after the resection of a single brain metastasis can be implemented without an increased risk of complications or mortality. Despite the stage IV disease, the median survival appears encouraging.

Gene Expression Analysis of the 26S Proteasome Subunit PSMB4 Reveals Significant Upregulation, Different Expression and Association with Proliferation in Human Pulmonary Neuroendocrine Tumours

Background: Proteasomal subunit PSMB4 was suggested to be a survival gene in an animal model of hepatocellular carcinoma and in glioblastoma cell lines. In pulmonary adenocarcinoma, a high expression of these genes was found to be associated with poor differentiation and survival. This study investigates the gene expression levels of 26S proteasome subunits in human pulmonary neuroendocrine tumours including typical (TC) and atypical (AC) carcinoid tumours as well as small cell (SCLC) and large cell (LCNEC) neuroendocrine carcinomas.

Material and methods: Gene expression levels of proteasomal subunits (PSMA1, PSMA5, PSMB4, PSMB5 and PSMD1) were investigated in 80 neuroendocrine pulmonary tumours (each 20 TC, AC, LCNLC and SCLC) and compared to controls. mRNA levels were determined by using TaqMan assays. Immunohistochemistry on tissue microarrays (TMA) was performed to determine the expression of ki67, cleaved caspase 3 and PSMB4.

Results: All proteasomal subunit gene expressions were significantly upregulated in TC, AC, SCLC and LCNEC compared to controls. PSMB4 mRNA is differently expressed between all neuroendocrine tumour subtypes demonstrating the highest expression and greatest range in LCNEC (p=0.043), and is significantly associated with proliferative activity (p=0.039).

Conclusion: In line with other 26S proteasomal subunits PSMB4 is significantly increased, but differently expressed between pulmonary neuroendocrine tumours and is associated with the proliferative activity. Unlike in pulmonary adenocarcinomas, no association with biological behaviour was observed, suggesting that increased proteasomal subunit gene expression is a common and probably early event in the tumorigenesis of pulmonary neuroendocrine tumours regardless of their differentiation.

Management of a chest-wall soft-tissue tumor caused by an infection with the larval tapeworm pathogen Taenia crassiceps

A chest-wall lesion of an immunocompetent patient was initially suspicious for a malignant tumor. Histopathological and polymerase chain reaction examinations revealed an infection with the larval stage of the tapeworm Taenia crassiceps. Curative resection of the tumorous lesion was performed. Treatment options for immunocompromised patients and patients without known immune defect are discussed, because most of the infections occur in immunocompromised individuals.

Mdm2 protein expression is strongly associated with survival in malignant pleural mesothelioma

ABSTRACT: 

Aims: TP53 mutations are extremely rare in malignant pleural mesothelioma (MPM). In TP53 wild-type tumors, the functional p53 protein can be inactivated by MDM2. Materials & methods: A total of 61 patient samples were tested for their Mdm2 and p53 protein expression levels via immunohistochemistry. Results: This study demonstrates nuclear Mdm2 expression in three out of four mesothelioma cell lines and 21.3% of the MPM specimens investigated. After silencing of the MDM2 gene by siRNA in MPM cell lines, Mdm2 immunoexpression is lost and cells show changes indicative of severe damage. Mdm2 protein expression in MPM is detected in epithelioid and biphasic subtypes only and is significantly associated with poor survival compared with Mdm2-negative tumors. This may be explained by increased Mdm2 levels possibly leading to an increased ubiquitilation and proteasomal degradation of functional p53 protein. Conclusion: Expression of Mdm2 is a strong prognostic factor associated with shortened overall survival in MPM.

[Diagnosis of pulmonary tuberculosis using Ziehl-Neelsen stain and polymerase chain reaction]

BACKGROUND

Definitive diagnosis of unclear pulmonary lesions is mainly based on morphological methods. In addition to a neoplasm, inflammatory reactions, in particular tuberculosis (TB), have to be considered in most cases. Therefore, the aim of this work was to determine whether established methods used in general pathology can be efficiently used with cytological material.

MATERIALS AND METHODS

An established polymerase chain reaction (PCR) protocol for the detection of Mycobacterium tuberculosis complex (Mtc) DNA in fixed specimens was conducted on fixed material available as an assay for liquid-based cytology (LBC). CytoLyt®-fixed material of 45 patients with clinically suspected TB or other mycobacteriosis were selected and were initially tested cytologically. In cases of absent tumor cells, PCR for detection of Mtc DNA and Ziehl-Neelsen stain (ZN) were performed.

RESULTS

In 9 patients (20 %), Mtc DNA was found by PCR. The following methods were used to obtain material: catheter biopsy (5), needle biopsy (2), transbronchial needle aspiration (1), and bronchoalveolar lavage (1). Cytologically an inflammatory reaction was observed in all cases. In 2 patients, a history of TB, in 2 further cases either silicosis or a posttransplant situation was known. In cases with a positive PCR, 7 patients (78 %) were positive in ZN and 3 patients (33.3 %) in TB culture (15.5 % vs. 6.7 % of the total cohort); however, the material used for investigation was not always from identical sources, respectively. In 36 out of 45 patients, both PCR and ZN were negative for the detection of Mtc DNA.

CONCLUSION

The material intended for LBC can be used for detection of TB with ZN and Mtc PCR.

"One-stop shop" spectral imaging for rapid on-site diagnosis of lung cancer: a future concept in nano-oncology

Background

There are currently many techniques and devices available for the diagnosis of lung cancer. However, rapid on-site diagnosis is essential for early-stage lung cancer, and in the current work we investigated a new diagnostic illumination nanotechnology.

Methods

Tissue samples were obtained from lymph nodes, cancerous tissue, and abnormal intrapulmonary lesions at our interventional pulmonary suites. The following diagnostic techniques were used to obtain the samples: endobronchial ultrasound bronchoscopy; flexible bronchoscopy; and rigid bronchoscopy. Flexible and rigid forceps were used because several of the patients were intubated using a rigid bronchoscope. In total, 30 tissue specimens from 30 patients were prepared. CytoViva® illumination nanotechnology was subsequently applied to each of the biopsy tissue slides.

Results

A spectral library was created for adenocarcinoma, epidermal growth factor receptor mutation-positive adenocarcinoma, squamous cell carcinoma, usual interstitial pneumonitis, non-specific interstitial pneumonitis, typical carcinoid tumor, sarcoidosis, idiopathic pulmonary fibrosis, small cell neuroendocrine carcinoma, thymoma, epithelioid and sarcomatoid mesothelioma, cryptogenic organizing pneumonia, malt cell lymphoma, and Wegener’s granulomatosis.

Conclusion

The CytoViva software, once it had created a specific spectral library for each entity, was able to identify the same disease again in subsequent paired sets of slides of the same disease. Further evaluation of this technique could make this illumination nanotechnology an efficient rapid on-site diagnostic tool.

Experimental respiratory syncytial virus infection of human peribronchial gland cells in vitro

Respiratory syncytial virus (RSV) is a relevant agent of respiratory tract infections, especially in exacerbations of chronic lung diseases. Peribronchial submucosal glands are the main source of tracheobronchial mucus and therefore of major interest. The authors isolated and cultured human peribronchial gland cells and infected them with RSV. The course of infection was monitored by transmission electron, immuno-, and lectin fluorescence microscopy. Morphology shows virus factories with budding particles within cytoplasmatic vacuoles and virus release after 44 h of infection. Experimental infection of human peribronchial gland cells in primary culture appears to be a suitable model in pulmonary research.

Assessment of SHOX2 methylation in EBUS-TBNA specimen improves accuracy in lung cancer staging

BACKGROUND

Endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA) is a well-established method to assess mediastinal lymph nodes for lung cancer. However, a proportion of patients require further investigation, due to the low negative predictive value (NPV). The objective of this study was to determine whether the assessment of short stature homeobox 2 (SHOX2) DNA methylation level in lymph node tissue obtained by EBUS-TBNA improves the accuracy of mediastinal staging.

PATIENTS AND METHODS

EBUS-TBNA was carried out for suspicious lymph nodes of 154 patients. Negative or ambiguous histological results were confirmed by surgical means and clinical follow-up over 6 months. EBUS-TBNA was assessed on 80 positive and 85 negative classified lymph nodes and compared with the result of the SHOX2 DNA methylation real-time PCR analysis. Relative methylation measured by delta-delta cycle threshold (ΔΔCt) was used to classify the samples. Clinical performance of the EBUS-TBNA procedure with and without the additional SHOX2 assessment was calculated against the final classification according to the gold standard.

RESULTS

Based on data from 105 patients, an average 80-fold increase in the SHOX2 methylation level was measured for positive compared with negative lymph nodes. SHOX2 results with a ΔΔCt value of <6.5 indicate positive lymph nodes. Applying this molecular analysis to EBUS-TBNA cases, not diagnosed by pathologic assessment, the sensitivity of staging was improved by 17%-99%. The NPV increased from 80% to 99%.

CONCLUSIONS

The combination of EBUS-TBNA and SHOX2 methylation level strongly improves the assessment of the nodal status by identifying additional malignant lesions and confirming benign nodes and therefore avoiding invasive follow-up procedures.