Molecular genetic characteristics of lung cancer--useful as real' tumor markers?

Investigation of NF-κB1 and NF-κBIA gene polymorphism in non-small cell lung cancer

Lung cancer is a complex, multifactorial disease which is the leading cause of cancer death in both men and women. NF-κB is a transcription factor which is known to affect the expression of more than 150 genes related to inflammation, lymphocyte activation, cell proliferation, differentiation, and apoptosis, as well as contributing to cell apoptosis and survival. However, NF-κBIA (IκBα) is the inhibitor of the transcription factor. The -94ins/delATTG polymorphism of the NF-κB1 gene promoter region which causes a functional effect and NF-κBIA 3′UTR A → G polymorphism has been shown to be related to various inflammatory diseases and cancer. Ninety-five NSCLC patients and 99 healthy controls were included in study. The NF-κB1 -94ins/delATTG and NF-κBIA 3′UTR A → G polymorphism have been studied by using PCR-RFLP method. It was found that the NF-κB1 -94ins/delATTG DD genotype and D allele frequencies were higher in patients than healthy controls and the presence of the DD genotype has a 3.5-fold increased risk of the disease (P: 0.014). This study is the first to investigate the NF-κB1 -94ins/delATTG and NF-κBIA 3′UTR A → G polymorphism together in the Turkish population. According to the results, the NF-κB1 -94ins/del ATTG promoter polymorphism may have a role in lung carcinogenesis and prognosis.

The relationship of metalloproteinase gene polymorphisms and lung cancer

BACKGROUND

We analyzed the relationship between matrix metalloproteinase (MMP)-2, -7, and -13 gene expression and polymorphisms and disease susceptibility and prognosis in patients who had undergone surgery for non-small-cell lung cancers.

MATERIALS AND METHODS

The study group consisted of 132 patients who had undergone radical surgery for non-small-cell lung cancers. The control group consisted of 80 healthy volunteers. We isolated deoxyribonuclease samples for use in analyzing gene polymorphisms from pathology blocks for the patient group and from blood samples for the control group. We identified MMP gene polymorphisms with polymerase chain reaction and restriction fragment length polymorphisms. Results were compared with those of the control group to evaluate disease susceptibility, correlation with other clinical parameters, and with survival and prognosis by using appropriate statistical methods.

RESULTS

When we compared polymorphisms pertaining to MMP genes in healthy controls and lung tumor DNA, we observed a decrease in the MMP-2 (-735) polymorphism GG genotype and increases in the MMP-13 (A77G) polymorphism AG and GG genotypes (P = 0.008, P = 0.047, and P = 0.047, respectively). For the MMP-7 (-181) polymorphism, the genotype did not differ significantly for disease susceptibility. Median overall survival time was 25.5 mo in the MMP-13 AA/AG genotypes and 9.3 mo in the GG genotype.

CONCLUSIONS

Decreases in the MMP-2 (-735) polymorphism GG genotype and increases in the MMP-13 (A77G) polymorphism AG and GG genotypes increase the risk for lung cancer. Furthermore, the presence of the MMP-13 (A77G) polymorphism GG genotype is an unfavorable prognostic factor.

K-ras mutation predictive significance in platinum based chemotherapeutic protocols in patients with advanced non-small cell lung cancer

Beckground/Aim. K-ras oncogene is mutated in about 20% of lung cancer. The purpose of this study was to investigate the predictive significance for therapeutic response of K-ras mutations in advanced non-small cell lung cancer (NSCLC) patients. Methods. Bronchial aspirate samples were assessed prior to platinum-based chemotherapy start in 39 patients with stage IIIb or IV NSCLC. K-ras mutations at codons 12 and 13 were analyzed by single strand conformation polymorphisam (SSCP) and allele specific oligonucleozide hybridisation of polymerase chain reaction (PCR) of the patient's DNA present in bronchial aspirate. After two cycles of chemotherapy the patients were subjected to response evaluation. Results. Of 39 patients 10 (25.5%) demonstrated K-ras mutations, while 29 (74.4%) patients had not. There were no significant differences between these two groups of patients with respect to baseline patient characteristics. Partial response to the therapy had 16 (41%), no changes 14 (36%), and progressive disease 9 (23%) patients. There was a tendency to higher response rate for patients without K-ras mutations versus those with mutations, but not statistically significant (p = 0.14). Conclusion. There was no significant predictive value for therapeutic response of K-ras mutations for advanced non-small cell lung cancer.

Combination therapeutic effect of cisplatin along with Solanum trilobatum on benzo(a)pyrene induced experimental lung carcinogenesis

Lung cancer is one of the leading causes of cancer death in the world and is notoriously difficult to treat effectively. In the present study, male Swiss albino mice were divided into five groups of six animals each: group I animals received corn oil orally and served as a control; group II cancer-induced animals received benzo(a)pyrene (B[a]P) (50 mg kg(-1) bodyweight dissolved in corn oil, orally) twice weekly for four successive weeks; group III cancer-bearing animals (after 12 weeks of induction) were treated with cisplatin (6 mg kg(-1) bodyweight, i.p.) once weekly for 4 weeks; group IV cancer-bearing animals were treated with cisplatin along with Solanum trilobatum (300 mg kg(-1) bodyweight) orally once weekly for 4 weeks; and group V animals constituted the drug control treated with cisplatin along with S. trilobatum. The serum, lung and liver were investigated biochemically for aryl hydrocarbon hydroxylase, gamma-glutamyl transpeptidase, 5'-nucleotidase, lactate dehydrogenase (LDH) and protein-bound carbohydrate components (hexose, hexosamine and sialic acid). These enzyme activities were increased significantly in cancer-bearing animals compared with control animals. The elevation of these in cancer-bearing animals was indicative of the persistent deteriorating effect of B[a]P in cancer-bearing animals. Our data suggest that cisplatin, administered with S. trilobatum, may extend its chemotherapeutic effect through modulating protein-bound carbohydrate levels and marker enzymes, as they are indicators of cancer. The combination of cisplatin with S. trilobatum could effectively treat the B[a]P-induced lung cancer in mice by offering protection from reactive oxygen species damage and also by suppressing cell proliferation.

Visualization-based cancer microarray data classification analysis

MOTIVATION

Methods for analyzing cancer microarray data often face two distinct challenges: the models they infer need to perform well when classifying new tissue samples while at the same time providing an insight into the patterns and gene interactions hidden in the data. State-of-the-art supervised data mining methods often cover well only one of these aspects, motivating the development of methods where predictive models with a solid classification performance would be easily communicated to the domain expert.

RESULTS

Data visualization may provide for an excellent approach to knowledge discovery and analysis of class-labeled data. We have previously developed an approach called VizRank that can score and rank point-based visualizations according to degree of separation of data instances of different class. We here extend VizRank with techniques to uncover outliers, score features (genes) and perform classification, as well as to demonstrate that the proposed approach is well suited for cancer microarray analysis. Using VizRank and radviz visualization on a set of previously published cancer microarray data sets, we were able to find simple, interpretable data projections that include only a small subset of genes yet do clearly differentiate among different cancer types. We also report that our approach to classification through visualization achieves performance that is comparable to state-of-the-art supervised data mining techniques.

AVAILABILITY

VizRank and radviz are implemented as part of the Orange data mining suite (http://www.ailab.si/orange).

SUPPLEMENTARY INFORMATION

Supplementary data are available from http://www.ailab.si/supp/bi-cancer.

Chemotherapeutic efficacy of paclitaxel in combination with Withania somnifera on benzo(a)pyrene-induced experimental lung cancer

Lung cancer is one of the leading causes of cancer death in the world and is notoriously difficult to treat effectively. In the present study, male Swiss albino mice were divided into five groups of six animals each: group I animals received corn oil orally and served as a control; group II cancer-induced animals received benzo(a)pyrene (50 mg/kg bodyweight dissolved in corn oil, orally) twice weekly for four successive weeks; group III cancer-bearing animals (after 12 weeks of induction) were treated with paclitaxel (33 mg/kg bodyweight, i.p.) once weekly for 4 weeks; group IV cancer-bearing animals were treated with paclitaxel along with Withania somnifera (400 mg/kg bodyweight) orally once weekly for 4 weeks; and group V animals constituted the drug control treated with paclitaxel along with W. somnifera. The serum, lung and liver were investigated biochemically for aryl hydrocarbon hydroxylase, gamma-glutamyl transpeptidase, 5'-nucleotidase, lactate dehydrogenase and protein-bound carbohydrate components (hexose, hexosamine and sialic acid). These enzyme activities were increased significantly in cancer-bearing animals compared with control animals. The elevation of these in cancer-bearing animals was indicative of the persistent deteriorating effect of benzo(a)pyrene in cancer-bearing animals. Our data suggest that paclitaxel, administered with W. somnifera, may extend its chemotherapeutic effect through modulating protein-bound carbohydrate levels and marker enzymes, as they are indicators of cancer. The combination of paclitaxel with W. somnifera could effectively treat the benzo(a)pyrene-induced lung cancer in mice by offering protection from reactive oxygen species damage and also by suppressing cell proliferation.

Loss of heterozygosity at loci of candidate tumor suppressor genes in microdissected primary non-small cell lung cancer

To investigate the etiological association of allelic loss at chromosomal regions containing tumor suppressor genes (TSGs) in non-small cell lung cancer (NSCLC) in Taiwan, we examined 48 microdissected NSCLC samples for loss of heterozygosity (LOH) at nine loci where TSGs are localized nearby. The associations of LOH at each locus with clinicoparameters and prognosis were also examined. The frequent LOH was observed using markers, D3S1285 near the FHIT gene (58.3%), D17S938 near the p53 gene (56.7%), D9S925 near the p16 gene (54.5%), and D13S153 near the RB gene (47.6%). The occurrence of LOH at each TSG locus was compared with the patients' clinicoparameters. The incidence of LOH at D17S938 (p53 gene) and D3S4545 (VHL gene) was significantly higher in squamous carcinoma tumors than in adenocarcinoma tumors (P = 0.003 and 0.024, respectively). LOH of these two loci also occurred frequently in tumors from smoker patients compared to that from nonsmoker patients (P = 0.013 and 0.025, respectively). LOH at D13S153 (RB gene) was also associated with smoking (P = 0.008). In addition, the prognostic analyses indicated that the patients with LOH at D18S535 (18q21, near the SMAD2/4 gene) had significantly longer post-operative survival time compared to those without LOH (P = 0.03). Our results suggested that LOH at FHIT, p53, and p16 genes may occur frequently in NSCLC patients in Taiwan. In addition, LOH at p53, RB, and VHL may associate with smoking or squamous carcinoma patients and LOH at SMAD2/4 may be correlated with better prognosis.

Topographical analysis of p53 expression and DNA ploidy in early bronchial squamous cell carcinoma and preneoplastic lesions

The significance of p53 mutations and DNA aneuploidy in carcinoma cells has been investigated on the basis of a multi-step development theory of carcinogenesis. It has, however, not been determined whether these alterations can be used as diagnostic markers for the early detection of bronchial squamous cell carcinoma (BSqCC). To address this problem, we topographically investigated p53 alterations and DNA aneuploidy in 24 X-ray-negative, early BSqCC patients with various preneoplastic lesions and in 25 non-carcinoma patients with preneoplastic lesions. Bronchial lesions (n=88) were morphologically classified as hyperplasia (HP, n=5), squamous metaplasia (SM, n=23), low-grade dysplasia (LGD, n=14), high-grade dysplasia (HGD, n=11), intraepithelial carcinoma including 'carcinoma in situ' (CIS) (IEC, n=15), and microinvasive carcinoma (MIC, n=20). Immunohistochemistry for the p53 protein and image cytometry for DNA ploidy detection were performed in serial sections of each lesion. Overexpression of p53 protein was detected in 36, 73, and 65% of the HGD, IEC, and MIC lesions, respectively. Aneuploid DNA profiles were found only in carcinoma lesions, 33% in IEC and 85% in MIC. The topographical analysis revealed two types of early BSqCCs, one with adjacent preneoplastic lesions (sequential type, n=8) and another without such lesions (de novo type, n=16). The p53 protein was frequently overexpressed in both types (sequential type, 79%; de novo type, 62%). In the sequential type, however, the p53 protein was overexpressed in HGD lesions that were directly adjacent to p53-overexpressing carcinoma lesions without exception. The present topographical study suggests that p53 mutations play an important role in the carcinogenesis of BSqCC and that p53-overexpressing HGD lesions in sequential types should be regarded as 'truly' preneoplastic lesions that actually develop into carcinomas. In addition, our study demonstrated that DNA aneuploidy might occur at times after p53 alteration with increasing frequency, as invasive growth begins. Such combination analysis of p53 immunohistochemistry and nuclear DNA ploidy in routine histology may contribute to estimates of malignant potential in preneoplastic and intraepithelial squamous lesions and provide additional information for early detection of BSqCC.

Combined modality therapy in NSCLC

Combined modality treatment has 'come out of age' and increasingly represents standard of care for a rapidly growing number of patients in locally advanced stages of NSCLC. Modern progress of treatment techniques as well as possibilities for supportive interventions will lead to lesser treatment toxicities, better patient's compliance to treatment protocols and combinations of different modalities with a more efficient outcome. This number will further increase, as more and more centres in Europe are setting up the logistics of multidisciplinary treatment groups for patients with lung cancer. Standard of care for most disease stages is currently under investigation in large randomised phase-III trials. Further research in the forthcoming years has to address questions of treatment individualisation (risks, prognosis, need for local control in the individual patient, biological evaluation of tumour aggressiveness, DNA-fingerprinting of tumours, evaluation of MRD-status, treatment in the community). New drugs or treatment principles with different mechanisms of action such as antiangiogenesis factors, signal-transduction inhibitors, immunotherapy, antisense-oligonucleotides or gene(replacement) therapy may stimulate further clinical research. This may eventually define 'new modalities of treatment' thus leading to modern 'second-generation combined-modality protocols' including some of the new principles.

Prognostic value of hyaluronan expression in non-small-cell lung cancer: Increased stromal expression indicates unfavorable outcome in patients with adenocarcinoma

The prognostic value of hyaluronan (HA) was analyzed in a large number of patients (n = 261) with non-small-cell lung cancer (NSCLC) by staining archived tumor samples with a biotinylated HA-specific probe. The level of HA in the tumor cells and surrounding stroma was scored and compared with parallel CD44 stainings, clinicopathological factors and survival data. Adenocarcinomas were characterized by a low percentage of HA-positive cells with low staining intensity compared with squamous-cell and large-cell/anaplastic carcinomas. The HA signal in the peri-tumoral stroma was often higher than that in the uninvolved stroma in all subgroups of NSCLC. CD44 and HA associated with the cancer cells showed a strong positive correlation with each other. In the whole tumor material, dominated by squamous-cell carcinomas (n = 168), recurrences were more often found in cases showing a low percentage of cancer cell-associated HA. However, within the adenocarcinoma subgroup (n = 68), a high percentage of cell-associated HA was correlated with poor tumor differentiation. Also specific for the adenocarcinoma subgroup was the increased number of recurrences in cases with a strong stromal HA signal. In survival analysis of the whole material (n = 189), a low percentage of HA-positive cancer cells was associated with a shortened disease-free survival (DFS) together with stage and tumor type. However, in the subgroup of patients with adenocarcinoma (n = 49), a strong stromal signal for HA predicted poor DFS. The level of HA in the stroma of adenocarcinomas retained its prognostic value in Cox's multivariate analysis. These results indicate that the frequency and intensity of HA has a significant prognostic value in NSCLC, particularly when the histological subtypes are analyzed as separate entities.

Predictive factors in radiotherapy for non-small cell lung cancer: present status

PURPOSE

To evaluate the predictive factors for radiation response in non-small cell lung cancer (NSCLC) and the role of such factors in guiding high dose radiation therapy.

METHODS

The first International Workshop on Prognostic and Predictive Factors in Lung Cancer was organized by the Hellenic Cooperative Oncology Group and held in Athens, Greece under the auspices of the International Association for the Study of Lung Cancer. Presentations at this meeting provided the outline of this report, which has also been supplemented with available data from the current literature.

RESULTS

The predictive factors for both the natural history and the therapy outcome of NSCLC are grouped as follows: (1) tumor related factors (anatomic factors); the extent of tumor (tumor stage) is one of most important prognostic factors affecting the therapy outcome. Tumor size (T stage), anatomical structures involved (T4 vs. T3 lesion), and the presence of regional lymph node metastasis have a significant impact on both prognosis and response to appropriate therapy; (2) host-related factors (clinical factors) that are important in therapy response include performance status, weight loss of more than 10% of body weight in the previous 6 months, and associated co-morbidities, i.e. pulmonary and cardiac diseases; (3) technical factors of radiation therapy which play a decisive role in successful outcome. The target volume should be defined accurately using modern imaging studies. The radiation dose fractionation schedule, in terms of the dose intensity and total dose, should be high enough to provide local tumor control in the majority of patients. Three-dimensional (3-D) conformal planning is an essential tool in dose escalation studies to determine the maximum tolerated dose of radiation; (4) biological/radiobiological/metabolic factors. Biologic markers resulting from genetic lesions in lung cancer are grouped as follows: (a) oncogene amplification and overexpression (aberrant gene expression) and mutated tumor suppressor genes -- ras gene, myc gene, HER-2/neu and survivin gene, p53 and mutated beta-tubulin gene; (b) tumor biologic/radiobiologic factors -- tumor cell proliferation kinetics, hypoxia, intrinsic cellular radiosensitivity, gamma factor, and DNA content; (c) enzymes and hormones: neuron-specific enolase, serum lactate dehydrogenase, and enhanced glucose metabolic rate supported by increased glucose transporter protein. The surviving fraction of tumor cells at 2.0 Gy of radiation (SF2) as a measure of intrinsic tumor cell radiosensitivity, potential doubling time (T(Pot)) as a measure of the rate of tumor cell proliferation and gamma factor representing the slope of the survival curve at 50% survival rate are being investigated as potential predictors for therapy response. Enhanced glucose utilization, a hallmark of malignant transformation, is being studied as a potential monitor for therapy response by using PET-FDG.

CONCLUSION

Current data indicate that there is a dose-response relationship between radiation dose and local tumor control, and also between local tumor control and survival in stage III NSCLC. Therapeutic factors, i.e. total radiation dose, fractionation schedule and dose intensity, and use of 3-D conformal radiation to secure the optimum therapeutic ratio are important for improved local tumor control and survival. Future research should be directed towards radiation dose escalation using 3-D conformal therapy to determine the maximum tolerated dose (MTD) of radiation in chemo-radiotherapy, and the use of this MTD for improved local tumor control and survival. Radiobiological, molecular, and metabolic markers may have potential for monitoring tumor response and optimizing radiation therapy.

Correlation of tumor size and survival in patients with stage IA non-small cell lung cancer

OBJECTIVE

The purpose of this study was to determine the relationship between tumor size and survival in patients with stage IA non-small cell lung cancer (non-small cell lung cancer; ie, lesions < 3 cm).

METHOD

Five hundred ten patients with pathologic stage IA (T1N0M0) non-small cell lung cancer were identified from our tumor registry over an 18-year period (from 1981 to 1999). There were 285 men and 225 women, with a mean age of 63 years (range, 31 to 90 years). The Cox proportional model was used to examine the effect on survival. Tumor size was incorporated into the model as a linear effect and as categorical variables. The Kaplan-Meier product limit estimator was used to graphically display the relationship between the tumor size and survival.

RESULTS

The Cox proportional hazards model did not show a statistically significant relationship between tumor size and survival (p = 0.701) as a linear effect. Tumor size was then categorized into quartiles, and again there was no statistically significant difference in survival between groups (p = 0.597). Tumor size was also categorized into deciles, and there was no statistical relationship between tumor size and survival (p = 0.674).

CONCLUSIONS

This study confirms stratifying patients with stage IA non-small cell lung cancer in the same TNM classification, given no apparent difference in survival. Unfortunately, these data caution that improved small nodule detection with screening CT may not significantly improve lung cancer mortality. The appropriate prospective randomized trial appears warranted.

Detection of microsatellite alterations in the DNA isolated from tumor cells and from plasma DNA of patients with lung cancer

In this paper, we show that the same panel of three microsatellite markers is useful for the detection of alterations in the DNA of tumor cells and plasma from patients diagnosed with SCLC and NSCLC. In 31% of the SCLC patients, we detected a microsatellite alteration(s) or LOH in at least one locus. In the group of patients diagnosed with NSCLC, a microsatellite alteration or LOH was detected in at least one locus in 33% of the patients. In all but 2 patients, the identical alteration observed in the DNA from tumor cells was also detected in the DNA isolated from blood plasma. This work confirms the results described by other groups and it extends the diagnostic possibilities of finding tumor cell-specific DNA alterations also in the DNA freely circulating in plasma and serum of patients with cancer.