Genetic polymorphisms in MMP 2, 9 and 3 genes modify lung cancer risk and survival.

BACKGROUND: Matrix metalloproteases (MMPs) are proteolytic enzymes that contribute to all stages of tumour progression, including the later stages of invasion and metastasis. Genetic variants in the MMP genes may influence the biological function of these enzymes and change their role in carcinogenesis and progression. We have investigated the association between the -735 C/T, the -1171 5A/6A, and the -1562 C/T polymorphisms in the MMP2, MMP3 and MMP9 genes, respectively, and the risk and survival of lung cancer. METHODS: The case-control study includes 879 lung cancer patients and 803 controls from a Caucasian population in Spain (CAPUA study). Genotypes were determined by PCR-RFLP. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression. The Kaplan-Meier method, long-rank test and Cox's were used for the survival analysis. RESULTS: The MMP9 -1562 T/T genotype was associated with a statistically significant decreased risk of developing lung cancer (OR = 0.23; 95% CI: 0.06-0.85), whereas no association was found for the MMP2 -735 C/T and MMP3 -1171 5A/6A polymorphisms. The MMP2 -735 T/T genotype was statistically significantly associated with a decreased survival in non-small cell lung cancer (NSCLC) patients, identified as an independent prognosis factor of survival (hazard ratio (HR) = 1.79; 95% CI: 1.00-3.20). In contrast, no association was found between the MMP3 -1171 5A/6A and the MMP9 -1562 C/T polymorphisms and survival. CONCLUSIONS: These findings support the hypothesis that the MMP9 -1562 C/T polymorphism is associated with a protective effect against the development of lung cancer and suggest that the MMP2 -735 C/T polymorphism modify the length of survival in NSCLC patients.

Germ-line mutations in epidermal growth factor receptor (EGFR) are rare but may contribute to oncogenesis: a novel germ-line mutation in EGFR detected in a patient with lung adenocarcinoma.

BACKGROUND: A subset of lung cancer patients harbour EGFR somatic mutations in their tumours and are candidates for treatment with EGFR tyrosine kinase inhibitors. In a few cases EGFR mutations have also been found in the germ line, suggesting a role in lung carcinogenesis. Objetives of this study were: 1) To analyze the EGFR gene mutations in a population diagnosed with lung adenocarcinoma from Northern Spain. 2) To determine the frequency of a new germ-line mutation found in our laboratory as well as the frequency in our population of three other EGFR germ-line mutations detected by other authors. 3) To determine whether the novel mutation detected may have a functional effect on the EGFR protein. METHODS: Tumour DNA samples were obtained from frozen or paraffin embedded tumour tissues. Samples of DNA from peripheral blood cells were obtained from 912 individuals with lung cancer recruited from the CAPUA study 12, 477 unrelated healthy donor individuals and 32 individuals with other types of cancer. EGFR gene exons 18 to 21 were studied by direct standard dideoxy sequencing. Specific mutations were determined either by direct sequencing or by specific RFLP analysis. Cell lines were transfected with EGFR-mutant plasmids and analysed by western blot with antibodies specific for total or phosphorylated-EGFR. RESULTS: We found EGFR mutation in 12 of the 71 tumour samples (17%). One tumour contained two mutations. One mutation (p.R776G) was present as a germ line. Using an RFLP analysis, this mutation was not found in 954 alleles from healthy individuals studied, concluding that it is not a polymorphism. The mutation was not found either in genomic DNA from 912 lung cancer patients. Three additional EGFR germ-line mutations that were already described were not found in any of the studied samples. These observations show that EGFR mutated alleles are rare in the population. In vitro studies revealed that tyrosine autophosphorylation is enhanced in p.R776G-mutant EGFR when compared with wild-type EGFR. This enhanced autophosphorylation in the absence of ligand may be associated with a proliferative advantage. CONCLUSIONS: Germ-line mutations in EGFR are rare but may contribute to oncogenesis.

Educational inequalities in quantity, duration and type of tobacco consumption among lung cancer patients in Asturias: epidemiological analyses.

Socioeconomic inequalities cause different tobacco consumption patterns. The purpose of this study was to examine the relationship between educational level and smoking behaviour, including type of tobacco consumption, in lung cancer patients. To this end, epidemiological analyses of 801 lung cancer patients recruited for a case-control study in four public hospitals in Asturias, Spain, between October 2000 and April 2006 were carried out. Smoking behaviour and educational level data were obtained through personal interview. Analyses indicated that the probability of heavy smoking among low educational-level patients was approximately twice as high as for high educational-level patients (RRR>31.2 packs/years=2.04; CI 95%=1.15-3.62; RRR>52packs/years=2.14; CI 95%=0.98-4.64). Low-educated patients were more than three times as likely to be long-time smokers (RRR>40 years=3.30; CI 95%=1.43-7.62). The probability of smoking exclusively black tobacco was almost four times greater in low educational-level patients (RRRblack only=3.72; CI 95%=1.23-11.19). The results show that there are broad educational inequalities with regard to the quantity, duration and type of tobacco consumption among lung cancer patients in Northern Spain.

Expression of matrix metalloproteinase-9 in prostate cancer. Preliminary experience.

OBJECTIVES: To study the validity of Matrix Metalloproteinase 9 as a complementary marker to PSA for the diagnosis and prognosis of Prostate Cancer. METHODS: Prospective study structured as a hospital-based cohort of 100 consecutive patients undergoing prostate biopsy. Serum determination of MMP-9 was carried out by means of inmunoassay. Statistical analysis was performed using the Stata/SE 8.2 software. RESULTS: 32 patients were diagnosed with prostate cancer and 52% had a Gleason score equal to or greater than 7. The values of serum MMP-9 varied between 225.7 and 1932.3 ng/ml, without significant differences among patients with benign, malignant and uncertain histology (p=0.429). The differences approached statistical significance in the subgroup of patients with PSA at 4-10 ng/ml (p=0.058), and significant differences were observed in the subgroup with free PSA to total PSA coefficient of less than 15% (p=0.037). No relationship between the Gleason score and the level of MMP-9 was shown (p=0.739). The levels of PSA and MMP-9 were shown to be independent (Pearson coefficient of correlation -0.1). CONCLUSIONS: It was not possible to show the efficacy of MMP-9 in predicting the result of the biopsy. In the group of patients with slightly increased levels of PSA (between 4 and 10 ng/ml) all the descriptive variables were higher in the group with malignant histology, though they did not reach statistical significance, they did reach significance when the coefficient of free PSA over total PSA was less than 15%, but this finding is not relevant clinically, as these patients already have a clear indication for biopsy. Neither was the relationship with the prognosis shown as there are no differences of MMP-9 expression at varying Gleason scores.

Matrix metalloproteinase- 9 polymorphisms in the diagnosis of prostate cancer. A preliminary experience.

UNLABELLED: Polymorphisms Q279R, P574R and -1562 C/T of matrix metalloproteinase-9 (MMP-9) gene have been linked with the risk of cancer and with tumoral aggressiveness in various types of cancer. So far there are no studies in the literature analysing the link between polymorphisms Q279R, P574R and -1562 C/T of MMP-9 and prostate cancer. OBJECTIVES: To establish the presence of the MMP-9's gene polymorphisms (Q279R, P574R and -1562 C/T)in relation to results of prostate biopsy, PSA values and Gleason score. METHODS: Hospital cohort of 100 patients with suspected prostate cancer, subjected to prostate biopsy, in whom the MMP-9 polymorphisms (Q279R, P574R and -1562 C/T) were analysed using the PCR-RLFP technique. RESULTS: No statistically significant differences were found in the presence of the Q279R, P574R and -1562 C/T polymorphisms in terms of prostate biopsy results (p = 0.264, p = 0.406, p = 0.860, respectively), or Gleason score (p = 0.373, p = 0.367, p = 0.476). Comparing the genotypes of the Q279R, P574R and -1562 C/T polymorphisms resulting from prostate biopsy, using subgroups according to PSA values, no statistically significant differences were found either (p = 0.332 y p = 0.393, respectively ). However, statistically significant differences were found when comparing the genotypes of the -1562 C/T polymorphism of the MMP-9 in patients showing positive biopsy for malignant tumour in comparison to a negative biopsy for a malignant tumour in the subgroup of patients with PSA 10 ng/ml (p=0.049). The joint analysis of the three MMP-9 polymorphisms, using logistical regression study did not reveal any statistically significant differences as far as the risk of developing prostate cancer is concerned based on the presence of the Q279R, P574R and -1562 C/T polymorphisms. CONCLUSION: The Q279R, P574R and -1562 C/T polymorphisms are not linked with the aggressiveness in prostate cancer, neither they are linked to the risk of suffering prostate cancer.

Polymorphism +17 C/G in matrix metalloprotease MMP8 decreases lung cancer risk.

BACKGROUND: Matrix metalloproteases (MMPs) constitute a family of enzymes capable of degrading different components of the extracellular matrix and are implicated in the invasion of tumor cells through the basement membrane. Polymorphisms in MMP genes may result in changes in the expression of MMPs being associated with the development and progression of cancer. We have investigated the association between three polymorphisms (-1607 1G/2G, +17 C/G and -77 A/G) in the human collagenases MMP1, MMP8 and MMP13 and the risk of development or progression of lung cancer. METHODS: A hospital-based case-control study was designed including 501 lung cancer patients and 510 controls matched. Genotypes were determined by PCR-RFLP. Results were analyzed using unconditional logistic regression, Cox's proportional hazard regression, and the Kaplan-Meier method. RESULTS: The MMP1 and MMP13 promoter polymorphisms were not associated with lung cancer risk, while the C/G polymorphism in MMP8 was associated with a statistically significant decreased risk of developing lung cancer (ORadj = 0.65; 95%CI = 0.45-0.93). The Kaplan-Meier analysis showed that the polymorphisms in MMP1, MMP8 and MMP13 not seem to modify the overall survival. Multivariate analysis revealed that MMP1, MMP8 and MMP13 polymorphisms are not independent prognostic factors for overall survival. CONCLUSION: This study suggests that the polymorphism in MMP8 is associated with a decreased lung cancer risk, which can be used as a prognostic marker in lung cancer.

The TP53 Arg72Pro polymorphism and lung cancer risk in a population of Northern Spain.

SUMMARY: Polymorphisms in tumor suppressor genes might contribute to the individual susceptibility to develop different types of cancer. Alterations in genes involved in cell cycle regulation and apoptosis, as tumor suppressor gene TP53, can lead to malignant transformations increasing the risk of developing cancer. We have investigated effects of polymorphism Arg72Pro on lung cancer risk, focusing on smoking and histology. Our study is a hospital-based case-control study designed with 589 lung cancer patients mainly with squamous cell carcinoma (215), adenocarcinoma (156) and small cell carcinoma (90), and 582 control subjects, matched in ethnicity, age and gender. Genotypes were determined by PCR-RFLP and the results were analysed using multivariate unconditional logistic regression, adjusted for age, gender and smoking status. The analysis showed a statistically significant increase of lung cancer risk in Pro carriers (Arg/Pro and Pro/Pro) (adjusted OR=1.32; 95% CI=1.03-1.69), especially for ever smokers (adjusted OR=1.34; 95% CI=1.04-1.73), heavy smokers (adjusted OR=1.48; 95% CI=1.01-2.16) and smokers of exclusively black tobacco (adjusted OR=1.45; 95% CI=1.04-2.00). Moreover, Pro carriers present an increased risk of developing small cell lung cancer (adjusted OR=1.70; 95% CI=1.07-2.69) and cancer in stage IV for NSCLC (adjusted OR=1.56; 95% CI=1.07-2.27). Our results suggest that polymorphism Arg72Pro in tumor suppressor gene TP53 increases the risk of lung cancer. The effect is especially strong for small cell lung cancer (SCLC) and heavy smokers.

Polymorphisms in XPC, XPD, XRCC1, and XRCC3 DNA repair genes and lung cancer risk in a population of northern Spain.

BACKGROUND: Polymorphisms in DNA repair genes have been associated to repair DNA lesions, and might contribute to the individual susceptibility to develop different types of cancer. Nucleotide excision repair (NER), base excision repair (BER), and double-strand break repair (DSBR) are the main DNA repair pathways. We investigated the relationship between polymorphisms in two NER genes, XPC (poly (AT) insertion/deletion: PAT-/+) and XPD (Asp312Asn and Lys751Gln), the BER gene XRCC1 (Arg399Gln), and the DSBR gene XRCC3 (Thr241Met) and the risk of developing lung cancer. METHODS: A hospital-based case-control study was designed with 516 lung cancer patients and 533 control subjects, matched on ethnicity, age, and gender. Genotypes were determined by PCR-RFLP and the results were analysed using multivariate unconditional logistic regression, adjusting for age, gender and pack-years. RESULTS: Borderline association was found for XPC and XPD NER genes polymorphisms, while no association was observed for polymorphisms in BER and DSBR genes. XPC PAT+/+ genotype was associated with no statistically significant increased risk among ever smokers (OR = 1.40; 95%CI = 0.94-2.08), squamous cell carcinoma (OR = 1.44; 95%CI = 0.85-2.44), and adenocarcinoma (OR = 1.72; 95%CI = 0.97-3.04). XPD variant genotypes (312Asn/Asn and 751Gln/Gln) presented a not statistically significant risk of developing lung cancer (OR = 1.52; 95%CI = 0.91-2.51; OR = 1.38; 95%CI = 0.85-2.25, respectively), especially among ever smokers (OR = 1.58; 95%CI = 0.96-2.60), heavy smokers (OR = 2.07; 95%CI = 0.74-5.75), and adenocarcinoma (OR = 1.88; 95%CI = 0.97-3.63). On the other hand, individuals homozygous for the XRCC1 399Gln allele presented no risk of developing lung cancer (OR = 0.87; 95%CI = 0.57-1.31) except for individuals carriers of 399Gln/Gln genotype and without family history of cancer (OR = 0.57; 95%CI = 0.33-0.98) and no association was found between XRCC3 Thr241Met polymorphism and lung cancer risk (OR = 0.92; 95%CI = 0.56-1.50), except for the 241Met/Met genotype and squamous cell carcinoma risk (OR = 0.47; 95%CI = 0.23-1.00). CONCLUSION: In conclusion, we analysed the association between XPC, XPD, XRCC1, and XRCC3 polymorphisms and the individual susceptibility to develop lung cancer in the Spanish population, specifically with a highly tobacco exposed population. We attempt to contribute to the discovery of which biomarkers of DNA repair capacity are useful for screening this high-risk population for primary preventing and early detection of lung cancer.