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Objective: To evaluate the application of traditional cytomorphology, telomerase activity analysis and immunocytochemistry in cytopathologic diagnosis of pleural effusion and bronchoalveolar lavage samples., Methods: A total of 123 agar-paraffin double-embedded pleural effusion and bronchoalveolar lavage fluid samples were enrolled into study. The cytomorphologic features were reviewed and correlated with immunocytochemical findings and telomerase activity., Results: Telomerase activity was detected in 53 specimens using the real-time telomeric repeat amplification protocol. Amongst the cases studied, 39 samples (31.7%) contained overtly malignant cells while 20 cases (16.0%) were equivocal by conventional cytology. After verification by immunocytochemistry and clinical follow-up data, the diagnostic accuracy of telomerase activity and cytology was 87.0% and 82.1%, respectively. The sensitivity (97.6%) and specificity (100.0%) of cytology examination, when combined with telomerase activity analysis, were greater than those of cytology examination or telomerase activity analysis alone., Conclusions: Telomerase activity analysis can be used as an adjunctive investigative tool in cytology assessment of pleural effusion and bronchoalveolar lavage samples. The diagnostic accuracy can be further improved with the application of immunocytochemistry on agar-paraffin double-embedded cell block tissues.

Lung cancer is the leading cause of cancer related deaths worldwide. It is necessary to better understand the molecular mechanisms involved in lung cancer in order to develop more effective therapeutics for the treatment of this disease. Recent reports have shown that Wnt signaling pathway is important in a number of cancer types including lung cancer. However, the role of Frizzled-8 (Fzd-8), one of the Frizzled family of receptors for the Wnt ligands, in lung cancer still remains to be elucidated. Here in this study we showed that Fzd-8 was over-expressed in human lung cancer tissue samples and cell lines. To investigate the functional importance of the Fzd-8 over-expression in lung cancer, we used shRNA to knock down Fzd-8 mRNA in lung cancer cells expressing the gene. We observed that Fzd-8 shRNA inhibited cell proliferation along with decreased activity of Wnt pathway in vitro, and also significantly suppressed A549 xenograft model in vivo (p<0.05). Furthermore, we found that knocking down Fzd-8 by shRNA sensitized the lung cancer cells to chemotherapy Taxotere. These data suggest that Fzd-8 is a putative therapeutic target for human lung cancer and over-expression of Fzd-8 may be important for aberrant Wnt activation in lung cancer., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Telomerase activity is found in various cell types including stem cells, neoplastic cells, and immortalized cells, suggesting a close association with their proliferation capacity. The telomeric repeat amplification protocol (TRAP) has been traditionally used to detect semi-quantitatively the telomerase activity by polyacrylamide gel electrophoresis (PAGE), which is difficult to apply for large scale analysis because of laborious post-PCR manipulation and potential carryover contamination. In the present study, a specific reverse primer was designed and the TRAP protocol was adapted to either PAGE or real-time PCR assay. Using cultured cell lines, the real-time TRAP showed a dramatic improvement in the reliability and accuracy of quantitation of telomerase activity and was able to discriminate the A549 cells from hundreds-fold human embryonic lung cells. Using clinical samples of 60 lung cancers and 8 inflammatory lesions, the real-time TRAP was also superior in quantitation, high-throughput capability and standardization. Our modified real-time TRAP should be applicable for the detection of telomerase activity for the initial screening and progression monitoring of lung cancer patients. Our approach is particularly useful when only limited clinical specimen is available, such as fine needle aspiration or other cytological specimens that may contain only a small number of tumor cells.

Somatic mutations in epidermal growth factor receptor (EGFR) tyrosine kinase domain, particularly deletions in exon 19 and point mutation in exon 21, are associated with clinical outcome in patients with lung adenocarcinoma, suggesting that EGFR mutation would have an important role in clinical decision making. DNA was extracted from the excised specimens of 60 lung adenocarcinoma patients with phenol-chloroform and ethanol precipitation. Exon 19 and 21 were amplified by PCR, and direct sequenced from both sense and antisense directions. EGFR somatic mutations were present in 13 of 60 patients (21.67%), including seven cases of in-frame deletion in exon 19 around codon 746 and six cases of amino acid substitution in exon 21. Exon 21 mutation is more frequent in adenocarcinomas with bronchi-alveolar component than exon 19 deletions. Mutations were more prevalent in well-differentiated adenocarcinomas (9/27, 33.33%) than in moderate to poor-differentiated adenocarcinomas (4/33, 12.12%) (P < 0.05). Adenocarcinomas with bronchi-alveolar components had higher mutation frequency (8/22,36. 36%) than those without bronchi-alveolar components (5/38, 13.16%) (P < 0.05). In this study, female patients had more mutation rate than male patients. This trend was also observed in the patients with pathologic stage I-II compared with stage III-IV, but neither of them was statistically significant. Patients with cisplatin-based adjuvant chemotherapy had no significantly prolonged survival compared with single radical resection. But patients with EGFR mutation had relative longer survival. In conclusion, our study suggest that EGFR mutations may be a valuable prognostic factor for disease free survival of surgically treated lung adenocarcinoma patients independently from adjuvant chemotherapy.

Objective: To investigate mutations of epidermal growth factor receptor (EGFR) exon 19 and 21 in non-small cell lung carcinoma and to explore their clinicopathological correlations., Method: DNA was extracted from the excised tumor specimens of 66 non-small cell lung carcinoma patients by traditional phenol-chloroform and ethanol precipitation. Exons 19 and 21 were amplified by polymerase chain reaction (PCR), followed by direct sequencing in both sense and antisense directions., Results: EGFR somatic mutations were present in 11 of 66 patients (16.7%), including 7 cases of in-frame deletion involving exon 19 and 4 cases of amino acid substitution involving exon 21. Mutations were more frequently observed in women (9/34, 26.5%) than in men (2/32, 6.3%), in adenocarcinomas (10/43, 23.3%) than squamous (0/13) and adenosquamous carcinomas (1/10). There was no difference in the mutation rates between smokers and non-smokers. Those with adenocarcinoma with bronchiolo-alveolar carcinoma (BAC) components had higher frequency of EGFR mutation (6/11) than those without non-BAC element (4/32, 12.5%)., Conclusions: The mutations appear to occur in highly selected subgroups of lung cancer patients: adenocarcinomas with BAC components and patients of the female gender. The results may offer practical approach to the rapid identification of lung cancer patients who likely respond to EGFR inhibitor therapy.

Background & Objective: Metastasis is one of the most important factors in determining the prognosis of lung cancer patients. However, it is difficult to determine single cancer cell in lymph nodes by routine methods. This study was designed to investigate a sensitive method for detecting lymph node micrometastases in human lung carcinomas., Methods: Mutation detection for p53 gene (exon 5-8) was performed in 39 cases of primary lung carcinomas and 110 corresponding lymph nodes (LNS) by PCR-TGGE method. Serial sectioning was performed to confirm micrometastases in some of these samples., Results: p53 mutations were found in 23 of 39 cases with primary lung cancer. Forty LNSs showed p53 mutation in 67 corresponding LNSs. They were located at the same exon as their primary tumors. Only twenty-six LNSs were detected metastases by routine histopathology. Forty-three LNSs from sixteen cases of primary tumor without p53 mutation and ten LNSs from the patients without tumor disease did not have any p53 mutations. By PCR-TGGE assay p53 gene mutations were determined in fourteen LNSs without histopathological evidence of metastasis. Micrometastases were found in four of the serially sectioned cases., Conclusion: Mutation detection for p53 gene (exon 5-8) showed lymph node micrometastases in patients with lung carcinoma. It may be used as a complement for the routine histopathology.