Identification of Wnt pathway, uPA, PAI-1, MT1-MMP, S100A4 and CXCR4 associated with enhanced metastasis of human large cell lung cancer by DNA microarray

AIM

The aim of this paper was to investigate the differentially expressed genes in large cell lung cancer cell lines with different metastatic potential, and to screen out new candidate genes related to metastasis of lung cancer.

METHODS

The total RNAs of low and high metastatic large cell lung cancer cell lines (NL9980 and L9981) were extracted and processed, then hybridized to Affymetrix HG U133 Plus 2.0 array. The hybridization signals were scanned and compared to find out the differentially expressed genes. Chosen genes were verified by Western Blot. Bioinformatics were used to analyze the functions and related pathways of the genes.

RESULTS

There were 933 differentially expressed genes between NL9980 and L9981 cell lines. In the high metastatic cell line L9981, 672 genes were up-regulated and 260 genes were down-regulated compared with the low metastatic cell line NL9980. The differentially expressed genes were mainly associated with binding, catalytic activity, signal transducer activity and transporter activity, and mainly involved in pathways including, pathways in cancer, focal adhesion, regulation of actin cytoskeleton, ECM-receptor interaction.

CONCLUSION

Differentially expressed genes with the functions including binding, catalytic activity, signal transducer activity and transporter activity may promote metastasis of lung cancer cells through complicated networks including Wnt pathway and metastasis-related genes such as uPA, PAI-1, MT1-MMP, S100A4 and CXCR4.

Impact of collection and storage of lung tumor tissue on whole genome expression profiling

Gene expression profiling could assist in revealing biomarkers of lung cancer prognosis and progression. The handling of biological samples may strongly influence global gene expression, a fact that has not been addressed in many studies. We sought to investigate the changes in gene expression that may occur as a result of sample processing time and conditions. Using Illumina Human WG-6 arrays, we quantified gene expression in lung carcinoma samples from six patients obtained at chest opening before and immediately after lung resection with storage in RNAlater [T1a((CO)) and T1b((LR))], after receipt of the sample for histopathology, placed in RNAlater [T2a((HP))]; snap frozen [T2b((HP.SF))]; or snap frozen and stored for 1 week [T2c((HP.SFA))], as well as formalin-fixed, paraffin-embedded (FFPE) block samples. Sampling immediately after resection closely represented the tissue obtained in situ, with only 1% of genes differing more than twofold [T1a((CO)) versus T1b((LR))]. Delaying tissue harvest for an average of 30 minutes from the operating theater had a significant impact on gene expression, with approximately 25% of genes differing between T1a((CO)) and T2a((HP)). Many genes previously identified as lung cancer biomarkers were altered during this period. Examination of FFPE specimens showed minimal correlation with fresh samples. This study shows that tissue collection immediately after lung resection with conservation in RNAlater is an optimal strategy for gene expression profiling.

Clinical application of MAGE A1-6 RT-nested PCR for diagnosis of lung cancer invisible by bronchoscopy

BACKGROUND

The main goal of this study was to evaluate the diagnostic efficacy of melanoma-associated antigen (MAGE) A1-6 reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) of bronchial washing fluid for the detection of lung cancer invisible by bronchoscopy.

PATIENTS AND METHODS

To determine the expression of MAGE A1-6 gene in 75 lung carcinomas diagnosed by conventional fluoroscopy-guided lung biopsy and 58 cancer-free controls, RT-nested PCR was performed of bronchial washing fluid. MAGE A1-6 RT-nested PCR data was analyzed according to tumor histology, stage, size, and compared with cytological data.

RESULTS

MAGE A1-6 RT-nested PCR displayed higher sensitivity (64.0%) than that of conventional cytology (14.7%). There was no significant correlation between MAGE gene expression and histological types or clinical stage. For tumor size, detection rates were 74.0% in tumor smaller than 3 cm and 58.7% in these larger than 3 cm.

CONCLUSIONS

MAGE A1-6 RT-nested PCR of bronchial washing fluid may be a useful method for diagnosis of peripheral lung cancer in clinical practice.

Vinorelbine versus paclitaxel for patients with advanced non-small cell lung cancer (NSCLC) and a performance status of 2

AIM

The purpose of this study was to compare two single agents paclitaxel (intravenous) versus vinorelbine (oral) in non-small cell lung cancer (NSCLC) patients with performance status (PS):2.

PATIENTS AND METHODS

The patients were randomized to receive either oral vinorelbine 60 mg/m(2) on days 1, 8, 15 every 4 weeks for 4 cycles (group A) or paclitaxel 90 mg/m(2) intravenously for 1 h on days 1, 8, 15 every 4 weeks for a total of 4 cycles (group B).

RESULTS

Among the 74 eligible patients (36 in arm A and 38 in arm B) in arm A, two (6%) had a partial response (95% CI, 0.7-18.7) and 5 (14%) had stable disease (95% CI, 4.7-29.5). In arm B, five (13%) had a partial response (95% CI, 4.4-28.1) and 7 (18%) had stable disease (95% CI, 7.7-34.3). No significant difference was found in terms of clinical benefit between the two groups after two cycles of treatment except for appetite in favour of paclitaxel (p=0.01). Median survival was 3.1 months (95% CI, 2.2-4.0) for arm A and 5.1 months (95% CI, 2.7-7.6) for arm B (p=0.95). Toxicity was mild and only alopecia was more profound in the patients of arm B (p=0.008).

CONCLUSION

No significant difference was found in clinical benefit between PS:2 NSCLC patients treated with either vinorelbine or paclitaxel.

[Epidermal growth factor receptor gene mutations and clinicopathologic correlation in 309 patients with non-small cell lung cancer]

OBJECTIVE

To investigate the epidermal growth factor receptor (EGFR) gene mutation profile and related clinicopathological features in Chinese patients with non-small cell lung carcinoma (NSCLC).

METHODS

Optimized oligonucleotide probe method was applied to detect EGFR mutations involving exons 18 - 21 using formalin fixed paraffin embedded tissue specimens of 309 NSCLC patients. The relationship between EGFR mutations and clinicopathological features were analyzed.

RESULTS

The overall EGFR mutation rate was 34% (105/309) in this study cohort. Mutation rates in male and female were 30.4% (56/184) and 39.2% (49/125), respectively. The mutation rate was higher in patients less than 60 years of age, non-smokers and adenocarcinoma subtype than in their counterparts (P<0.05), with the percentage of 40.5% (87/215), 40.2% (51/127), 38.8% (78/201), respectively. The EGFR mutation types included exon 18 G719X mutation (5.7%, 6/105), exon 19 deletion (39.0%, 41/105) and exon 21 L858R mutation (55.2%, 58/105). In large cell undifferentiated carcinomas and squamous cell carcinomas, EGFR mutation rates were 22.2% (58/105) and 3/14, respectively. The overall mutation rate of exon 18 was low, but the proportion of its mutation was higher in squamous and adenosquamous carcinomas than in adenocarcinomas.

CONCLUSIONS

There is a higher EGFR mutation rate in female, age of less than 60 years, non-smoker and adenocarcinoma among Chinese patients with NSCLC. Optimized oligonucleotide probe method is a sensitive and convenient method for the detection of EGFR mutations.

Screening for EGFR and KRAS mutations in endobronchial ultrasound derived transbronchial needle aspirates in non-small cell lung cancer using COLD-PCR

EGFR mutations correlate with improved clinical outcome whereas KRAS mutations are associated with lack of response to tyrosine kinase inhibitors in patients with non-small cell lung cancer (NSCLC). Endobronchial ultrasound (EBUS)-transbronchial needle aspiration (TBNA) is being increasingly used in the management of NSCLC. Co-amplification at lower denaturation temperature (COLD)–polymerase chain reaction (PCR) (COLD-PCR) is a sensitive assay for the detection of genetic mutations in solid tumours. This study assessed the feasibility of using COLD-PCR to screen for EGFR and KRAS mutations in cytology samples obtained by EBUS-TBNA in routine clinical practice. Samples obtained from NSCLC patients undergoing EBUS-TBNA were evaluated according to our standard clinical protocols. DNA extracted from these samples was subjected to COLD-PCR to amplify exons 18–21 of EGFR and exons two and three of KRAS followed by direct sequencing. Mutation analysis was performed in 131 of 132 (99.3%) NSCLC patients (70F/62M) with confirmed lymph node metastases (94/132 (71.2%) adenocarcinoma; 17/132 (12.8%) squamous cell; 2/132 (0.15%) large cell neuroendocrine; 1/132 (0.07%) large cell carcinoma; 18/132 (13.6%) NSCL-not otherwise specified (NOS)). Molecular analysis of all EGFR and KRAS target sequences was achieved in 126 of 132 (95.5%) and 130 of 132 (98.4%) of cases respectively. EGFR mutations were identified in 13 (10.5%) of fully evaluated cases (11 in adenocarcinoma and two in NSCLC-NOS) including two novel mutations. KRAS mutations were identified in 23 (17.5%) of fully analysed patient samples (18 adenocarcinoma and five NSCLC-NOS). We conclude that EBUS-TBNA of lymph nodes infiltrated by NSCLC can provide sufficient tumour material for EGFR and KRAS mutation analysis in most patients, and that COLD-PCR and sequencing is a robust screening assay for EGFR and KRAS mutation analysis in this clinical context.

Efficacy of gefitinib for non-adenocarcinoma non-small-cell lung cancer patients harboring epidermal growth factor receptor mutations: a pooled analysis of published reports

The efficacy of gefitinib for patients with non-adenocarcinoma non-small-cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations is unclear, because only a small percentage of patients enrolled in the clinical trials to evaluate the efficacy of gefitinib for tumors harboring EGFR mutation were non-adenocarcinoma NSCLC. A pooled analysis was conducted to clarify the efficacy of gefitinib for non-adenocarcinoma NSCLC patients harboring EGFR mutations. A systematic search of the PUBMED databases was conducted to identify all clinical reports that contained advanced non-adenocarcinoma NSCLC patients harboring EGFR mutations and treated with gefitinib. The selected patients were advanced non-adenocarcinoma NSCLC patients harboring EGFR mutations who were treated with gefitinib and described in reports containing the data of the histology, status of EGFR mutations and response to gefitinib. This study selected 33 patients from 15 reports. Twenty-seven and three of the 33 patients were squamous cell carcinoma and adenosquamous cell carcinoma, respectively. One patient each had large-cell carcinoma, pleomorphic carcinoma and spindle cell carcinoma. Twenty-one patients (64%) had sensitive EGFR mutations. The response rate (RR), disease control rate (DCR) and median progression-free survival (mPFS) was 27%, 67-70% and 3.0 months, respectively. These factors were statistically significantly inferior in the non-adenocarcinoma NSCLC patients harboring EGFR mutations to adenocarcinoma patients harboring EGFR mutations selected from the same published reports (RR: 27%vs 66%, P = 0.000028; DCR: 67-70%vs 92-93%, P = 0.000014; mPFS: 3.0 vs 9.4 months, P = 0.0001, respectively). Gefitinib is less effective in non-adenocarcinoma NSCLC harboring EGFR mutations than adenocarcinoma harboring EGFR mutations.

Lack of any relationship between chemotherapy toxicity in non-small cell lung cancer cases and polymorphisms in XRCC1 codon 399 or XPD codon 751

PURPOSE

To examine the association between genetic polymorphisms (at XRCC1codon 399 or XPD codon 751) and chemotherapy related toxicities of non-small cell lung cancer.

METHODS

One hundred and fifteen patients with histologically or cytologically confirmed stage IIIB and IV NSCLC recruited from Department of Chemotherapy of Jiangsu Cancer Hospital and Research Institute from 2005 to 2008, to evaluated the occurrence of chemotherapy related toxicities and the association with single nucleotide polymorphisms in XRCC1codon 399 or XPD codon 751.

RESULTS

No significant association was observed between grade 0 or grade 1-4 overall toxicity and XRCC1 codon 399 (odds ratio=1.40, 95% confidence interval,0.73-2.66; adjusted odds ratio =1.43, 95% confidence interval,0.71-2.88), or XPD codon 751 genetic polymorphisms (odds ratio =0.87, 95% confidence interval,0.33-2.26; adjusted odds ratio=0.74, 95% confidence interval,0.26-2.13); similar results were found between hematologic, hepatic, gastrointestinal toxicities and XRCC1 399 or XPD 751 genetic polymorphisms.

CONCLUSION

No statistically significant association was found between either XRCC1codon 399 or XPD codon 751 genetic polymorphisms and chemotherapy related toxicities.

[Comparative proteomics study on human high-metastatic large cell lung cancer cell lines before and after transfecting with nm23-H1 gene]

BACKGROUND

As a tumor metastasis suppressor gene, the functions of nm23-H1 gene are still unclear. The aim of this study is to better understand the mechanism of lung cancer metastasis and to find new biomarkers for early diagnosis and new target for therapy by conducting comparative proteomics between the human high-metastatic large cell lung cancer cell lines (L9981) and L9981-nm23-H1 (constructed with transfecting nm23-H1 gene into the L9981 cell line).

METHODS

The total proteins of L9981 and L9981-nm23-H1 were separated by immobilized pH gradient (IPG)-based 2-dimensional electrophoresis (2-DE); the significantly differently expressed proteins were examined by mass spectrometry and analyzed by bioinformatics.

RESULTS

It was observed that nm23-H1 gene transfection caused remarkable changes of the proteome of L9981 compared with L9981-nm23-H1 cells: 5 proteins were deleted, 9 proteins appeared, 16 proteins downregulated, and 12 proteins up-regulated. These proteins are involved in cell framework, signal transduction, metabolism, proliferation and metastasis.

CONCLUSIONS

After nm23-H1 gene is transfected into L9981, proteome in L9981 is remarkably changed. These changes of the proteome could serve as a basis for reversing the invasive and metastatic phenotype in lung cancer and elucidating the mechanisms of the metastasis of lung cancer.

Multidisciplinary approach in diagnosis of lung carcinoma

AIM

To employ multidisciplinary approach in order to make the correct diagnosis of lung carcinoma clinically and morphologically mimicking lymphoma.

METHODS

Immunostaining was performed by incubating tissue sections with appropriate antibodies, using the streptavidin-biotin technique. Antigen-antibody complexes were visualized with 3-amino-9-ethylcarbasole or diaminobenzidine hydrochloride substrate solution. We have investigated p53 gene mutations by polymerase chain reaction and DNA sequence analysis of exons 5, 6, 7, 8 and 9.

RESULTS

Tumor cells expressed cytokeratin AE1/AE3, epithelial membrane antigen (EMA) and thyroid transcription factor-1 (TTF-1) without thyreoglobulin positivity. Further, tumor cells expressed neuroendocrine mar kers: synaptophysin, chromogranin A, neuron-specific enolase (NSE), CD56/NCAM, CD57/Leu-7 and protein gene product 9.5 (PGP9.5). P53 was also expressed. Diffuse large cell lymphomas of B and T cell origin were excluded. Direct sequencing analysis of exon 6 of the p53 gene revealed ATC to ACC mutation at codon 195. Final diagnosis of large cell lung neuroendocrine carcinoma (LCNEC) was established.

CONCLUSIONS

Morphological pattern of tumor complied with large cell non-Hodgkin's lymphoma, but large cell lung carcinoma with neuroendocrine differentiation was proved immunohistochemically and confirmed by genetic analysis of p53 mutations in tumor tissue sample. Multidisciplinary approach in diagnosis of lung carcinoma is useful for its final diagnosis.

WWOX gene may contribute to progression of non-small-cell lung cancer (NSCLC)

Lung cancer is the most common cause of cancer-related death worldwide and, like many other cancers, is affected by different genetic, epigenetic, and environmental factors. The WW domain-containing oxidoreductase (WWOX) gene is a tumor-suppressor gene located on chromosome 16q23.3-24.1, and it has been shown that it loses its function due to alterations in genetic and epigenetic mechanisms. The aim of this study is to investigate the relationship between lung cancer and WWOX gene. Tumor tissue samples, corresponding normal tissues, and blood samples obtained from 50 lung cancer patients were involved in the study. We analyzed methylation profile by methylation-specific PCR and mutations and polymorphisms by DNA sequencing. Methylation analysis showed that promoter hypermethylation was present in 38 of 50 (76%) patients. In addition, promoter region of WWOX gene of younger patients was more frequently methylated than older patients. Using DNA sequencing, we found four genetic alterations in WWOX gene. Two of them were germline mutations (Exon 4 and 7), and two of them were polymorphic (Exon 6 and 8). We found a new mutation in exon 7 (Arg-254-->Cys) which has not been described previously. The changes in the short-chain dehydrogenase domain of the protein caused by the genetic alterations may affect the function of the gene. We conclude that hypermethylation of WWOX gene promoter region and mutations in the gene might be related to lung carcinogenesis.

Insulin-like growth factor receptor 1 (IGF1R) gene copy number is associated with survival in operable non-small-cell lung cancer: a comparison between IGF1R fluorescent in situ hybridization, protein expression, and mRNA expression

PURPOSE

The purpose of this study was to characterize insulin-like growth factor-1 receptor (IGF1R) protein expression, mRNA expression, and gene copy number in surgically resected non-small-cell lung cancers (NSCLC) in relation to epidermal growth factor receptor (EGFR) protein expression, patient characteristics, and prognosis.

PATIENTS AND METHODS

One hundred eighty-nine patients with NSCLC who underwent curative pulmonary resection were studied (median follow-up, 5.3 years). IGF1R protein expression was evaluated by immunohistochemistry (IHC) with two anti-IGF1R antibodies (n = 179). EGFR protein expression was assessed with PharmDx kit. IGF1R gene expression was evaluated using quantitative reverse transcription polymerase chain reaction (qRT-PCR) from 114 corresponding fresh-frozen samples. IGF1R gene copy number was assessed by fluorescent in situ hybridization using customized probes (n = 181).

RESULTS

IGF1R IHC score was higher in squamous cell carcinomas versus other histologies (P < .001) and associated with stage (P = .03) but not survival (P = .46). IGF1R and EGFR protein expression showed significant correlation (r = 0.30; P < .001). IGF1R gene expression by qRT-PCR was higher in squamous cell versus other histologies (P = .006) and did not associate with other clinical features nor survival (P = .73). Employing criteria previously established for EGFR copy number, patients with IGF1R amplification/high polysomy (n = 48; 27%) had 3-year survival of 58%, patients with low polysomy (n = 87; 48%) had 3-year survival of 47% and patients with trisomy/disomy (n = 46; 25%) had 3-year survival of 35%, respectively (P = .024). Prognostic value of high IGF1R gene copy number was confirmed in multivariate analysis.

CONCLUSION

IGF1R protein expression is higher in squamous cell versus other histologies and correlates with EGFR expression. IGF1R protein and gene expression does not associate with survival, whereas high IGF1R gene copy number harbors positive prognostic value.

Large cell lung carcinoma with unusual imaging feature, immunophenotype and genetic finding

We present a case of large cell lung carcinoma in sixty-one year old male with typical lung cancer symptoms but unusual radiological presentation and immunophenotype. Tumor morphological finding related to its radiological finding was suggestive for large cell lymphoma or carcinoma, but its immunophenotype made confusion for pathological diagnosis. No p53 mutations were detected in genetic investigation. Multidisciplinary diagnostic approach to some tumors is useful for their final diagnosis.

[Expression of Gemcitabine-resistance-related gene and polymorphism of ribonucleotide reductase M1 gene promoter in Gemcitabine-resistant A549/Gem and NCI-H460/Gem cell lines]

OBJECTIVE

To assay the expression of cytidine deaminase (CDA), ribonucleotide reductase subunit 1 (RRM1), phosphatase and tensin homologue deleted from chromosome 10 (PTEN), excision repair cross-complementation group 1 (ERCC1), deoxycytidine kinase (dCK) and RRM1(-)37A/C polymorphism, which have been shown relevant to gemcitabine resistance in two human gemcitabine-resistant non-small cell lung cancer cell lines A549/Gem and NCI-H460/Gem, so as to make clear how do they vary during the course of acquiring resistance to gemcitabine.

METHODS

The human gemcitabine-resistant non-small cell lung cancer cell lines A549/Gem and NCI-H460/Gem were established in our Department by repeated clinical serum peak concentration and gradually increasing doses. Real-time fluorescent quantitative PCR was used to examine the expression of CDA, RRM1, PTEN, ERCC1, dCK and RRM1(-)37A/C polymorphism in those cell lines at different time points during their induction process.

RESULTS

The resistance indexes of A549/Gem and NCI-H460/Gem cells reached 163.228 and 181.684, and then remained stable at 115.297 and 129.783, respectively. The expression of CDA, RRM1, PTEN and ERCC1 varied along with the changing gemcitabine resistance indexes, but expression of dCK did not change apparently. The wild type promoter was able to amplify the genomic DNA in different induction stages of A549/Gem and NCI-H460/Gem cells, but allelotype did not, indicating that the gene type of A549/Gem, NCI-H460/Gem and their parental cells remaining still wild type.

CONCLUSION

Compared with their parental cells, the expressions of CDA, RRM1, PTEN and ERCC1 in human gemcitabine-resistant non-small cell lung cancer cell lines A549/Gem and NCI-H460/Gem rise, the expression of dCK changes inapparently, therefore, their gene type are remaining wild type.

The relationship between methylation of the Syk gene in the promoter region and the genesis of lung cancer

BACKGROUND

To study the expression of the Syk (Spleen Tyrosine Kinase) gene and methylation in its promoter region in lung cancer. To investigate the relationship between silencing of the Syk gene and DNA methylation of the Syk promoter region.

METHODS

RT-PCR (Semi-quantitative reverse transcription PCR), Real-time PCR (Real-time quantitative PCR) and immunohistochemistry technique, the expression of Syk in specimens from 3 lung cancer cell lines and 16 lung cancer patients (tumor tissues and adjacent normal tissues). MSP (Methylation-specific PCR) was used to analyze the methylation status of the Syk promoter region. Then we also investigated the role of restoring Syk expression by using a DNA methyltransferase inhibitor, 5-aza-CdR (5-aza-2'-deoxycytidine), in suppressing invasion of lung cell lines.

RESULTS

No expression of the Syk gene was detected in the 3 lung cancer cell lines. In the 16 lung patient samples, Syk expression was significantly lower in the tumor tissues than in the adjacent normal tissues (P < 0.05). Consistently, immunohistochemistry analyses of Syk protein expression showed that in the cancer tissues Syk protein expression accounted for 5% (1/20), and in the adjacent normal tissues the rate of expression was 100% (20/20). The correlation was highly significant (chi2 = 36.19, P < 0.005). In the only case that showed a positive expression of cancer textus, the level was inferior to the adjacent tissue. In the two lung cancer cell lines (L9981, A549) that lack the endogenous Syk epression, 4uM demethylation agent 5-aza-CdR treatment was able to reactivate the Syk gene expression.

CONCLUSIONS

Hypermethylation leads to silencing of the Syk gene in human lung carcinoma. Methylation of the Syk promoter and loss of Syk expression in lung cancer are independent biomarkers, a determination which may offer guidance for selecting appropriate diagnoses and treatments. Syk may be a potential tumor suppressor in human lung cancer.

Novel spliced form of a lens protein as a novel lung cancer antigen, Lengsin splicing variant 4

A glutamine synthetase I family protein, Lengsin, was previously identified as a novel lens-specific transcript in the vertebrate eye. In this report, we show for the first time that Lengsin is a novel tumor-associated antigen expressed ectopically in lung cancer. Interestingly, a novel spliced form of human Lengsin termed 'splicing variant 4', gaining exon 3 that codes extra 63 amino acids, is the dominant transcript form in lung cancer cells. Lengsin mRNA could be detected in 7 of 12 (58%) lung cancer cell lines and 7 of 7 (100%) surgically resected lung cancer tissues. On the other hand, Lengsin transcripts could not be detected in normal major tissues or in other cancer cell lines, including melanoma, colorectal carcinoma, breast carcinoma and hepatocellular carcinoma. In addition, knockdown of Lengsin mRNA with RNAi caused cell death and a decrease of cell viability, suggesting that Lengsin has some essential role in cell survival. Since the lens is an immune-privileged site, we regard Lengsin as a highly immunogenic cancer antigen. Anti-Lengsin autoantibodies were detectable in sera of lung cancer patients, although these patients did not show any lens-related disturbances. Hence, Lengsin splicing variant 4 might be an immunogenic lung cancer-specific antigen that is suitable as a diagnostic marker and for molecular targeting therapy, including immunotherapy.

The role of the homeobox genes BFT and CDX2 in the pathogenesis of non-small cell lung cancer

BACKGROUND

The role of the homeobox genes Backfoot (BFT) and caudal-related Homeobox 2 (CDX2) in the pathogenesis of non-small cell lung cancer (NSCLC) is unclear. The goal of this study was to investigate the mRNA expression of BFT and CDX2 in NSCLC and to determine the association with the pathogenesis and the potential as a biomarker of this disease.

MATERIALS AND METHODS

The mRNA expression of BFT and CDX2 was analyzed by quantitative real-time RT-PCR in the tumor and matching normal tissue from 23 patients with NSCLC.

RESULTS

The mRNA expression was detectable with the following frequencies in the tumor (t) and normal (n) tissues: BFT=100% (n), 100% (t); CDX2=100% (n), 100% (t). The median CDX2 mRNA expression was 0.85 (range: 0.01-15.47) in the tumor tissue and 0.045 (range: 0-1.36) in the matching normal lung tissue (p=0.001). The median BFT mRNA expression was 0.0034 (range: 0-0.35) in the tumor tissue and 0.0001 (range: 0-0.10) in the matching normal lung tissue (p=n.s.). There were no associations between the mRNA expression levels of BFT and CDX2 and clinicopathological variables.

CONCLUSION

The mRNA expression of the homeobox genes is detectable at a high frequency in the tumor and normal tissue of patients with non-small cell lung cancer. Up-regulation of CDX2 mRNA expression appears to be associated with the pathogenesis of this malignant disease. The quantification of CDX2 and BFT mRNA expression in lung tissue is a potential biomarker for the identification of patients at risk of the development of NSCLC.

Increased human telomerase reverse transcriptase (hTERT) mRNA expression but not telomerase activity is related to survival in curatively resected non-small cell lung cancer

BACKGROUND

The purpose of this study was to evaluate the significance of human telomerase reverse transcriptase (hTERT) mRNA expression and telomerase activity as prognostic markers in non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

In a series of 69 curatively resected NSCLC specimens, telomerase activity was analyzed with the telomeric repeat amplification protocol (TRAP) assay and expression of hTERT mRNA by quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Partitioning of gene expression levels and protein activities to construct prognostic groups was attempted.

RESULTS

Human hTERT mRNA transcripts were detected in 62 (89.9%) cases of NSCLC. Seven (10.1%) tumors were completely negative for hTERT expression. Dichotomized hTERT levels (<0.42 versus > or =0.42) were associated with prognosis and Kaplan-Meier survival curves demonstrated a significant difference (log rank: p<0.01) with 5-year survival rates of 44.3% (+/-7.1%) for low as compared to 80% (+/-8.9%) for high hTERT mRNA expression. Low hTERT expression was also significantly associated with squamous cell histology (p<0.03). Telomerase activity was not associated with survival, stage, pT and pN categories, histological type or grading. Comparison of hTERT mRNA expression and telomerase activity was possible in 66 patients and showed a significant difference (p<0.0001) by Wilcoxon rank test.

CONCLUSION

This is the first study which demonstrates that high hTERT mRNA expression is associated with improved 5-year survival rates. Expression patterns are distinct among histopathological subtypes of NSCLC and telomerase activity (TRAP) is significantly higher than hTERT mRNA expression.

Lack of influence of XRCC1 and XPD gene polymorphisms on outcome of platinum-based chemotherapy for advanced non small cell lung cancers

PURPOSE

Genetic polymorphisms of DNA repair genes are associated with differential enzyme activity and may help explain interindividual differences in response rates after platinum-based chemotherapy for non small cell lung cancers (NSCLCs). This study was conducted to assess relationships between X-ray repair cross complementing group1 (XRCC1) and xeroderma pigmentosum group D (XPD) genetic polymorphisms and outcome in NSCLC patients.

METHODS

From March 1, 2005 to December 31, 2008, the polymerase chain reaction-restriction fragment length polymorphism method was applied to evaluate genetic polymorphisms of the XRCC1 codon399 (Arg/Gln) and XPD codon751 (Lys/Gln) DNA repair genes in 108 patients with stage IIIB and IV NSCLCs treated with platinum-based chemotherapy in the Department of Chemotherapy of Jiangsu Cancer Hospital and Research Institute.

RESULTS

Among the assessed NSCLC patients, the overall response rate of chemotherapy was 21.6%. No association was found with either of the genetic polymorphisms, although the XRCC1 399Arg/Arg genotype was associated with a non-significant higher median survival time (29 months versus 21 months for the Arg/Gln genotype and 15 months for the Gln/Gln genotype, P= 0.09).

CONCLUSION

Our results suggested no influence of the XRCC1 codon399 (Arg/Gln) and XPD codon751 (Lys/Gln) genetic polymorphisms on treatment response and survival in advanced NSCLC patients with platinum-based chemotherapy.

[Comparative proteomic analysis of human large cell lung cancer cell line with high and low metastasis potentials]

OBJECTIVE

A comparative proteomic analysis on two human large cell lung cancer strains with high metastasis potential (L9981) and low metastasis potential (NL9980) were conducted.

METHODS

The total proteins of the two cell lines were separated by immobilized pH gradient (IPG )-based two-dimensional gel electrophoresis. The differential expression proteins of the two cell lines were analyzed using image analysis software. Thirteen differential expressed proteins were further identified using in-gel digestion with trypsin, of which peptide extracts were prepared for MALDI-TOF MS/MS analysis by Daltonics AutoFlex TOF-TOF LIFT Mass Spectrometer (Bruker). Protein identifications were searched in the NCBInr protein database using the Mascot search engine.

RESULTS

Protein image analysis indicated that 8 protein spots were observed only in L9981, not in NL9980; 8 protein spots were observed only in NL9980, not in L9981; 19 protein spots were detected in both L9981 and NL9980, of which 9 showed significantly higher volumes in L9981 than in NL9980 and 10 showed significantly higher volumes in NL9980 than in L9981. MS and biological informatics study found that the expressions of heat shock 70 kD protein 9B precursor, MTHSP75 and glutathione synthetas incerased in L9981 cells. However, a variant of P47 protein, immunoglobulin heavy chain variable region, enolasel, heat shock protein and eukaryotic translation initiation fact 3 were down-regulated in L9981 cells. Pyruvate kinase (PK) was only expressed in L9981 cells while WD-40 repeat protein was only expressed in NL9980 cells.

CONCLUSIONS

The metastatic lung cancer cell lines display different protein profiles compared to the non metastatic lung cancer cell lines. The identified proteins are likely to be associated with tumor metastasis, 4hich could serve as a basis for searching potential prognosis markers of lung cancer and elucidating the mechanisms of the metastasis of lung cancer.

Frequent down-regulation of pim-1 mRNA expression in non-small cell lung cancer is associated with lymph node metastases

Pim kinases are emerging as important mediators of cytokine signalling pathways in hematopoietic cells, and contribute to the progression of certain leukemias and solid tumors. The mRNA expression of pim-1, a putative oncogenic serine-threonine kinase, was determined in non-small cell lung cancer (NSCLC) patients. Sixty-eight patients with potentially curative resections (R0 resections) for NSCLC in histopathological stages I-IIIA were included. An analysis of pim-1 mRNA expression was performed on paired tumor and normal lung tissue samples by quantitative real-time reverse transcriptase-PCR (RT-PCR) standardized for beta-actin. Pim-1 expression in the tumor (median 0.28) was significantly down-regulated (p<0.0001) compared to the paired normal tissue (median 4.96). Immunohistochemistry showed a strong expression of Pim-1 protein in the normal respiratory epithelium and a lower expression in the tumor cells. A significant association between the pim-1 down-regulation and occurrence of lymph node metastases (p=0.05) was detected. The down-regulation of pim-1 mRNA was demonstrated for 59 out of 68 lung cancer patients (86.8%). Down-regulation occurs already in the early stage of NSCLC and is either directly involved in the lymphatic progression in NSCLC or represents a surrogate marker.

Soy consumption reduces the risk of non-small-cell lung cancers with epidermal growth factor receptor mutations among Japanese

Epidermal growth factor receptor (EGFR) mutations play substantial roles in genesis and proliferation of non-small-cell lung cancers (NSCLCs). We recently found that reproductive factors have a substantial impact on risk of development of NSCLCs featuring such EGFR mutations. Therefore, we explored the influence of dietary habits on NSCLC risk with reference to the EGFR mutational status. We conducted a case-control study using 353 patients with NSCLCs (122 EGFR mutated and 231 EGFR wild-type) and 1765 age-sex matched non-cancer control subjects. Dietary exposure was based on a semiquantitative food frequency questionnaire and impact of major food items, like meats, seafoods, vegetables and soybean products was assessed by multivariate logistic regression. Soybean products demonstrated a protective association with EGFR mutated, but not EGFR wild-type NSCLCs, with multivariate-adjusted odds ratios and 95% confidence intervals for the 2nd and 3rd tertile of soybean product consumption of 0.79 (0.50-1.27) and 0.56 (0.34-0.93) relative to those in the lowest tertile (trend P = 0.023). In conclusion, soy consumption may exert a protective association against the development of NSCLCs with EGFR mutations, providing possible insights into mechanisms of their genesis.