Single nucleotide polymorphisms of integrin alpha-2 and beta-3 genes are not associated with relapse-free and overall survival in colorectal cancer patients

BACKGROUND

Integrins influence tumourigenesis, tumor progression and development of metastases. The impact of polymorphisms in integrin genes on relapse-free survival (RFS) and overall survival (OS) for 433 Caucasian patients with colorectal cancer was analysed in this retrospective study.

PATIENTS AND METHODS

A Cox regression model including integrin genotype, age, grading, tumour size, number of lymph nodes examined, number of metastatic lymph nodes, stage and application of fluorouracil-based adjuvant chemotherapy was used to estimate their effect.

RESULTS

After a median follow-up of 41 months for RFS and 55 months for OS, no significant correlation between the ITGA2 1648A allele (RFS p=0.618, OS p=0.604), the ITGA2 807T allele (RFS p=0.603, OS p=0.807) and the ITGB3 176C allele (RFS p=0.719, OS p=0.261) and survival was detectable.

CONCLUSION

The investigated integrin polymorphisms are not associated with RFS or OS in colorectal cancer patients.

Association between single nucleotide polymorphisms in the gene for XRCC1 and radiation-induced late toxicity in prostate cancer patients

BACKGROUND AND PURPOSE

Polymorphisms in genes responsible for DNA damage signaling and repair might modulate DNA repair capacity and, therefore, affect cell and tissue response to radiation and influence individual radiosensitivity. The purpose of the present prospective investigation was to evaluate the association of single nucleotide polymorphisms in XRCC1 with radiation-induced late side effects in prostate cancer patients treated with radiotherapy.

MATERIAL AND METHODS

To analyze the role of XRCC1 polymorphisms for late toxicity 603 participants from the Austrian PROCAGENE study treated with three-dimensional conformal radiotherapy were included in the present investigation. Three non-synonymous candidate polymorphisms in the X-ray repair cross-complementing group 1 (XRCC1) gene (Arg194Trp; Arg280His; Arg399Gln) were selected and determined by 5´-nuclease (TaqMan) assays.

RESULTS

Within a median follow-up time of 35 months, 91 patients (15.7%) developed high-grade late toxicities (defined as late bladder and/or rectal toxicity RTOG≥2). In a Kaplan-Meier analysis, carriers of the XRCC1 Arg280His polymorphism were at decreased risk of high-grade late toxicity (p=0.022), in multivariate analysis including clinical and dosimetric parameters as potential confounders the XRCC1 Arg280His polymorphism remained a significant predictor for high-grade late toxicity (HR=0.221, 95% CI 0.051-0.956; p=0.043). No significant associations were found for the remaining polymorphisms.

CONCLUSIONS

We conclude that the XRCC1 Arg280His polymorphism may be protective against the development of high-grade late toxicity after radiotherapy in prostate cancer patients.

Impact of CYP2D6*4 genotype on progression free survival in tamoxifen breast cancer treatment

OBJECTIVE

The cytochrome P450 2D6 (CYP2D6) polymorphism was reported to have a significant impact on outcome of tamoxifen treatment in estrogen receptor positive breast cancer patients. The objective of this study was to explore the effect of the CYP2D6*4 polymorphism on tamoxifen treatment outcome in a cohort of patients from a single clinical trial which included women with a history of previous chemotherapy.

RESEARCH DESIGN AND METHODS

A total of 493 patients of the Austrian TIGER study receiving adjuvant tamoxifen therapy were studied for this pharmacogenetic interaction. All women with estrogen receptor positive tumors and tamoxifen therapy longer than 6 months were genotyped for CYP2D6*4 using TaqMan technology. Time to tumor progression, defined as local, regional, distant recurrence or contralateral breast cancer and progression free survival, was analyzed.

RESULTS

No significant difference in time to tumor progression or progression free survival between the CYP2D6*4 genotype groups in the overall study cohort was found. In a subgroup of patients treated with chemotherapy the CYP2D6*4 poor metabolizers had a tendency towards a shorter mean time to progression. In this group the mean time to tumor progression and the progression free survival were 1.0 years in the CYP2D6*4/*4 group, 6.3 years in the *1/*4 group and 4.97 years in the *1/*1 group (Wilcoxon p = 0.104).

CONCLUSION

While earlier data on CYP2D6 and tamoxifen excluded women with prior chemotherapy, the present analysis suggests that CYP2D6*4 genotype might be particularly crucial in this group of high-risk patients. Key limitations are restriction to the CYP2D6*4 allele and missing data of comedication.

Single nucleotide polymorphisms in the hypoxia-inducible factor-1 gene and colorectal cancer risk

With an incidence of about 300 000 new cases colorectal cancer (CRC) is the second leading cause of cancer-related death in Europe and the United States. Environmental and genetic factors influence CRC risk. Hypoxia-inducible factor-1 (HIF-1), a heterodimeric protein composed of two subunits, HIF-1 alpha and HIF-1 beta, plays a critical role in oxygen homeostasis and is involved in angiogenesis and cell proliferation. The gene for the HIF-1 alpha subunit (HIF1A) carries two common missense mutations-P582S (rs11549465) and A588T (rs11549467)-which both have been related to increased trans-activation capacity of HIF1A. In our case-control study we investigated the association between these polymorphisms and CRC risk. We investigated 381 patients with histologically confirmed CRC and 2156 control subjects. HIF1A genotypes were determined by exonuclease (TaqMan) assays. For determination of microvessel density (MVD) tumor sections were stained using a mouse monoclonal antibody recognizing the pan-endothelial marker CD31. In a multivariate logistic regression analysis including age and sex neither the HIF1A 582S allele (Odds ratio: 1.204; 95% confidence interval 0.911-1.592; P = 0.193) nor the 588T allele was significantly associated with CRC (Odds ratio: 0.851; 95% confidence interval 0.444-1.631; P = 0.626). However, in an exploratory analysis, the HIF1A 588T allele was associated with tumor localization (P = 0.016) and tumor size (P = 0.003). MVD was similar in tumors of patients carrying HIF1A 588T allele and patients without this rare allele. We conclude that functional polymorphisms in the HIF1A gene do not modify CRC risk but maybe associated with clinic-pathological features of the disease.

Association of hypoxia-inducible factor 1-alpha gene polymorphisms and colorectal cancer prognosis

BACKGROUND

Hypoxia inducible factor-1 (HIF-1) is the key regulator of cellular responses to hypoxia and plays a central role in tumour growth. Recently, two single nucleotide polymorphisms (SNPs) in the HIF-1 alpha gene, C1772T and G1790A, were shown to cause significantly higher transcriptional activity than did the wild-type. This study aimed to investigate the effect of these SNPs on the prognosis of colorectal cancer (CRC).

PATIENTS AND METHODS

DNA from 336 CRC patients was genotyped. Genotypes of each polymorphism were tested for association with disease-free survival (DFS) using univariate and multivariate Cox-regression analysis.

RESULTS

Genotype frequencies were: CC 75.6%, CT 18.8% and TT 1.8% for HIF1A1 C1772T and GG 93.2%, GA 2.7% and AA 0% for G1790A. A statistically significant association between DFS and clinicopathological features was observed. However, no association was found between HIF1A1 C1772T (p=0.44; risk ratio of recurrence, RR=1.19, 95% confidence interval, CI=0.77 to 1.83) and G1790A (p=0.89; RR=0.92, 95% CI=0.29 to 2.90) polymorphisms and DFS in univariate and multivariate Cox-regression analysis.

CONCLUSION

These results suggest that HIF1A1 C1772T and G1790A polymorphisms are not involved in the progression or metastasis of CRC.

The Functional Promoter Polymorphism of the Coagulation Factor XII Gene is not Associated With Peripheral Arterial Disease

Coagulation factor XII (FXII) plays a key role in both coagulation and fibrinolysis and has been associated with cardiovascular disease in some studies. Plasma FXIIa levels are strongly determined by a common functional polymorphism in the promoter of the FXII gene (F12-4C>T). To investigate the potential association of this polymorphism with peripheral arterial disease (PAD), we performed a case-control study including 668 patients with PAD and 762 controls participants without cardiovascular disease. F12 genotype frequencies were not significantly different between patients with PAD and control participants. After adjustment for classical risk factors, the odds ratio of carriers of a F12 -4T allele for PAD was 1.06 (95% confidence interval 0.86—1.32). F12 genotypes were associated with a modest increase of the mean-activated partial thromboplastin time but not with PAD stage or severity. We conclude that the functional F124C>T polymorphism is not associated with PAD.

A common hereditary single-nucleotide polymorphism in the gene of FAS and colorectal cancer survival

Apoptosis plays an important role in embryogenesis, autoimmunity and tumourigenesis. Cell surface death receptors such as TNFRSF6 (FAS) confer a major apoptotic effect. A single-nucleotide polymorphism in the FAS promoter gene, −670A/G, modulates apoptotic signalling and has been related to susceptibility and progression of a variety of cancers. The present study aimed to evaluate the role of this polymorphism for survival of patients with colorectal cancer. We performed a retrospective analysis including 433 patients with histologically confirmed colorectal cancer. A Cox regression model including FAS -670 genotypes, age at diagnosis, tumour grading, primary tumour size, number of lymph nodes examined, number of metastatic lymph nodes, tumour stage and application of fluorouracil-based adjuvant chemotherapy was used to estimate the effect of the FAS genotype on survival. FAS −670A/G genotype frequencies were 24.2% (AA), 46.3% (AG) and 29.5% (GG). Forty-nine patients were excluded from the Cox regression analysis because of missing values. Out of the remaining 384 patients, 69 (18%) died during a follow-up of maximum 10 years. Mean follow-up time was 58 ± 34 months (median 55 months). Carriers of the homozygous FAS -670GG genotype had a significantly lower survival rate compared with AA/AG genotype carriers (relative risk 1.76, 95% confidence interval 1.08–2.87; P= 0.023). The FAS −670A/G polymorphism may be associated with overall survival time of patients with colorectal cancer.

The role of radiation therapy after incomplete resection of penile cancer

PURPOSE

To retrospectively assess the outcome in patients treated with adjuvant radiotherapy for penile cancer.

PATIENTS AND METHODS

Between 1987 and 2006, 24 patients (median age, 62.7 years; range, 35.5-90.4 years) with squamous cell carcinoma of the penis (T1, n = 10; T2, n = 11; T3, n = 3) received megavoltage external radiotherapy (n = 22) or (192)Ir high-dose-rate brachytherapy (n = 2) following total penectomy (n = 7), partial penectomy (n = 10), or local excision (n = 7); lymphadenectomy was performed in eight patients. In 14 patients, radiotherapy was delivered after incomplete tumor resection, and in 20 patients the planning target volume included the regional lymph nodes. Median total dose of external radiotherapy was 56 Gy/1.8-2 Gy (range, 50-60 Gy). Brachytherapy was given with a total dose of 45 Gy/3 Gy.

RESULTS

During a median follow-up of 58.4 months, penile or perineal recurrence was found in four patients giving a 5-year local control rate of 74.8%. Regional failure occurred in two patients. 5-year metastases-free survival and progression-free survival rates were 86.7% and 64.5%, respectively. Four patients died due to tumor progression. The actuarial 5-year cause-specific and overall survival rates were 84.3 and 56.6%, respectively.

CONCLUSION

Radiation therapy is a successful method of treatment for penile cancer in terms of local control and organ preservation after microscopically incomplete surgery. Radiotherapy of the regional lymph nodes might also be effective in preventing regional recurrence and can be considered in case of high-risk features and following excision of extensive lymph node involvement.

Single nucleotide polymorphisms and haplotypes in the gene for vascular endothelial growth factor and risk of prostate cancer

Vascular endothelial growth factor (VEGF) plays a key role in the regulation of angiogenesis and has been related to cancer development and progression. To evaluate the role of VEGF single nucleotide polymorphisms (SNPs) and haplotypes in prostate cancer, we performed a case-control study including 702 prostate cancer patients and 702 male age-matched healthy control subjects. Seven VEGF candidate polymorphisms were determined by 5'-nuclease (TaqMan) assays. Furthermore, VEGF plasma levels and genotypes were analysed in a group of 64 healthy men. Haplotype analysis showed two separate blocks of high-linkage disequilibrium, formed by five polymorphisms upstream of the coding sequence (promoter and 5'-untranslated region) and two polymorphisms downstream of the coding sequence. None of the single polymorphisms or haplotypes was significantly associated with the presence of prostate cancer. In a multivariate regression analysis including age, VEGF genotypes and haplotypes as covariates and VEGF plasma level as dependent variable, none of the VEGF polymorphism or haplotypes was a significant predictor of VEGF plasma levels. The present data suggest that polymorphisms or haplotypes in the VEGF gene do not modify the risk of prostate cancer.

In vivo confocal laser scanning microscopy of melanocytic skin tumours: diagnostic applicability using unselected tumour images

BACKGROUND

In vivo confocal laser scanning microscopy (CLSM) represents a novel imaging tool that allows the noninvasive examination of skin cancer morphology in real time at a 'quasi-histopathological' resolution viewing microanatomical structures and individual cells.

OBJECTIVES

To validate diagnostic confocal examination of melanocytic skin tumours using unselected tumour images.

METHODS

In the present study, we used a total of 3709 unselected CLSM tumour images obtained from 20 malignant melanomas and 50 benign naevi. The entire set of images derived from each tumour was evaluated by independent observers. Classification tree analysis based on a subsample of 857 tumour images was performed to develop a diagnostic algorithm.

RESULTS

Overall, sensitivity and specificity of 97.5% and 99% could be achieved by the independent observers (positive predictive value 97.5%, negative predictive value 99%). Classification tree analysis yielded a three-step algorithm based on only three morphological CLSM features, facilitating a correct classification in 92.4% of the benign naevus images and 97.6% of melanoma images.

CONCLUSIONS

In vivo CLSM augurs a sea change in the way we will view skin tumour processes clinically at the bedside and merits application for use as a screening tool in skin oncology.

The Glu228Ala polymorphism in the ligand binding domain of death receptor 4 is associated with increased risk for prostate cancer metastases

BACKGROUND

Death receptor 4, encoded by the TNFRSF10A gene, is an important mediator of apoptosis and its dysfunction may be related to cancer development and distant tumor spread. A single nucleotide polymorphism in TNFRSF10A (Glu228Ala, rs20576) within a conserved region of the extracellular cysteine-rich domain of death receptor 4 has been associated with an increased risk for a variety of tumor entities. Aim of the present study was to evaluate the role of the TNFRSF10A polymorphism in metastatic progression of prostate cancer after radiation therapy.

METHODS

We carried out a prospective study including 702 prostate cancer patients from the Austrian PROCAGENE (Prostate Cancer Genetics) study. Development of metastases was examined in regular follow-up investigations. TNFRSF10A genotypes were determined by a 5'-nuclease assay (TaqMan).

RESULTS

Within a median follow-up time of 10 months (range 0-60 months), 24 (3.4%) patients developed metastases. In a Cox regression model including age at diagnosis and risk group as potential confounders, carriage of an 228Ala allele was associated with a relative risk of 2.47 (95% CI 1.10-5.54; P=0.028) for metastases. TNFRSF10A genotypes were not associated with tumor stage, grade, risk group or age at diagnosis.

CONCLUSION

We conclude that the TNFRSF10A Glu228Ala polymorphism may be a novel independent risk factor for prostate cancer metastases after radiation therapy.

Genetic polymorphisms in the vascular endothelial growth factor gene and breast cancer risk. The Austrian "tumor of breast tissue: incidence, genetics, and environmental risk factors" study

PURPOSE

Vascular endothelial growth factor (VEGF) is a key regulator of tumor-induced angiogenesis and is required for growth of tumors. We tested the hypothesis that VEGF gene polymorphisms may be associated with breast cancer.

EXPERIMENTAL DESIGN

We performed a case-control study including 804 female incident breast cancer patients and 804 female age-matched healthy control subjects. We selected seven VEGF candidate polymorphisms and determined genotypes by 5'-nuclease (TaqMan) assays. Furthermore, VEGF plasma levels and genotypes were analyzed in a group of 81 healthy volunteers (64 men and 17 women).

RESULTS

Haplotype analysis showed two separate blocks of high-linkage disequilibrium, formed by five polymorphisms upstream of the coding sequence (promoter and 5' untranslated region) and two polymorphisms downstream of the coding sequence. None of the single polymorphisms or haplotypes was significantly associated with the presence of breast cancer. After Bonferroni correction for multiple testing, only one statistical signifcant association between VEGF genotypes and haplotypes and tumor characteristics was observed (-634C allele and small tumor size; p < 0.001). In a multivariate regression analysis including sex, age, VEGF genotypes, and haplotypes as covariates and VEGF plasma level as dependent variable, none of the VEGF polymorphism or haplotypes was a significant predictor of VEGF plasma levels.

CONCLUSIONS

Our findings do not support the hypothesis that VEGF polymorphisms are associated with breast cancer risk. The association of the VEGF -634C allele with small tumor size is in clear contrast to a previous publication and should be interpreted with caution until replicated by additional studies.

The use of confocal laser-scanning microscopy in microsurgery for invasive squamous cell carcinoma

BACKGROUND

Ex-vivo confocal laser-scanning microscopy offers rapid imaging of excised tissue specimens without conventional histotechnical procedures. As vertical sections are prepared, morphological features can be assessed according to standard criteria used in conventional histopathology.

OBJECTIVES

To validate the diagnostic confocal examination of squamous cell carcinoma (SCC) in microscopy-guided surgery.

METHODS

Four independent observers received standardized instructions about diagnostic confocal microscopy features of SCC. Subsequently, 120 confocal images of fresh excisions from SCC or normal skin, imaged using a commercially available, near-infrared, reflectance confocal laser-scanning microscope, were evaluated by each observer.

RESULTS

General morphology, such as location, size and shape of the cancer area could be visualized by the imaging system. Furthermore, densely packed and irregularly organized nuclei and nuclear atypia could be delineated. Overall, a sensitivity of 95% and a specificity of 96.25% were achieved by the four observers (positive predictive value 96.25%, negative predictive value 95.23%).

CONCLUSIONS

This study provides a set of well-described morphological criteria with obvious diagnostic impact which should be used in further investigations. In the future, confocal laser-scanning microscopy may guide microsurgery of any skin cancer.

Long-Term Follow-up of Patients with Pituitary Macroadenomas after Postoperative Radiation Therapy

PURPOSE

Evaluation of long-term tumor control, normalization of hormonal hypersecretion, including incidence and time course of pituitary dysfunction following postoperative radiotherapy of pituitary macroadenomas.

PATIENTS AND METHODS

In a retrospective study, the data of 87 patients with pituitary macroadenomas (61 non-secreting adenomas, 26 secreting adenomas) treated between 1984 and 1994 were analyzed. All patients underwent surgery and received postoperative external-beam radiotherapy with a mean dose of 50.4 Gy (range 46-54 Gy).

RESULTS

After a follow-up of 15 years the local tumor control rate achieved was 93.0% for non-secreting adenomas and 100% for secreting adenomas, respectively. Normalization of endocrine hypersecretion was noted in 24 of 26 patients (92%). Detailed endocrinological follow-up data were analyzed by an experienced endocrinologist in 77 patients. After a median follow-up of 10.54 years (mean 10.22; range 1.39-20.75 years), in 75 of 77 patients (97%) a hypopituitarism was observed (partial hypopituitarism, n = 28 [36%], panhypopituitarism, n = 47 [61%]), and 68 out of 77 patients (88%) showed evidence of radiotherapy-induced pituitary disorders. The somatotropic function was most commonly affected, followed by gonadal, thyroid and adrenal function. The gonadal axis showed to be the first to be disturbed. 67 patients (87%) required a hormone replacement therapy.

CONCLUSION

Radiotherapy after pituitary surgery is highly effective in reducing hormonal hypersecretion and preventing recurrences of pituitary adenomas. However, pituitary insufficiencies are commonly observed after radiotherapy requiring a close follow-up to ensure timely diagnosis of pituitary dysfunction and an early inception of hormone replacement therapy.

Methylenetetrahydrofolate reductase (MTHFR) and breast cancer risk: a nested-case-control study and a pooled meta-analysis

Encouraged by recent studies on the MTHFR 677C>T polymorphism and breast cancer risk that suggested an association of the 677 TT genotype with increased breast cancer susceptibility in premenopausal women, we performed an analysis of the relationship between breast cancer risk and the MTHFR 677C>T polymorphism in 210 premenopausal breast cancer patients and sex- and agematched healthy control subjects. Our data show a trend for a higher MTHFR 677T allele frequency in breast cancer cases (61.9%) than in controls (51.5%, P = 0.082) supporting the results of previous studies.