Prevalence of BK Virus and Human Papillomavirus in Human Prostate Cancer

Polyomaviruses such as the BK virus (BKV), JC virus (JCV) and SV40, as well as the human papillomaviruses (HPV) are frequently detected throughout human populations, causing subclinical persistent infections and inducing oncogenesis in human and other cell lines. To test the involvement of these viruses in prostate tumorigenesis, we investigated the prevalence of BKV, JCV and HPV in a series of human prostatic malignancies. Forty-two samples of diagnosed prostatic malignancies were tested using standard polymerase chain reaction (PCR) protocols. Differentiation between BKV and JCV among the polyomavirus-positive samples was achieved after sequencing analysis of the PCR products. Reconstitution of BKV in vitro was performed and indirect immunofluorescence for the large T-antigen of the virus was applied to confirm the production of progeny virus. Detection and typing of HPV was carried out by PCR. The overall prevalence of polyomaviruses was 19% in the prostate cancer cases. Sequencing analysis of the polyomavirus-positive specimens revealed the presence of BKV in all samples. Reconstitution of the BKV from the BKV-positive prostate samples was successfully achieved in cell culture and progeny viral particles were obtained, confirming the presence of the virus in the human biopsies. HPV was detected in 4.8% of the samples, however, no HPV-11, HPV-16, HPV-18 or HPV-33 types were identified. BKV was frequently detected and could play a relevant role in the development and progression of human prostate cancer, whereas HPV does not seem to be implicated in this type of human neoplasia.

Expression of YKL-40 and MIP-1a proteins in exudates and transudates: biomarkers for differential diagnosis of pleural effusions? A pilot study

Background

YKL-40 is an extracellular matrix glycoprotein with a significant role in tissue inflammation and remodeling. MIP-1a has chemotactic and pro-inflammatory properties, and is induced by YKL-40 in several lung disorders. The aim of this study was to determine the levels of YKL-40 and MIP-1a in blood serum and pleural fluids of various pulmonary diseases, and to evaluate their potential role as differential diagnosis biomarkers.

Methods

We recruited 60 patients (age: 62.5 ± 20.6 years) with pleural effusions: 49 exudates and 11 transudates (T). Exudates were further classified based on the underlying disease: ten with tuberculosis (TB), 13 with lung cancer (LCa), 15 with metastatic cancer (MCa) of non-lung origin and 11 with parapneumonic (PN) effusions. YKL-40 and MIP-1a levels were measured by ELISA.

Results

Pleural YKL-40 levels (ng/ml) were similar among all patient groups (TB: 399 ± 36, LCa: 401 ± 112, MCa: 416 ± 34, PN: 401 ± 50, T: 399 ± 42, p = 0.92). On the contrary, YKL-40 was significantly lower in the serum of TB patients (TB: 58 ± 22, LCa: 212 ± 106, MCa: 254 ± 140, PN: 265 ± 140, T: 229 ± 123, p < 0.001). Pleural MIP-1a protein levels (ng/ml) were statistically lower only in patients with LCa (TB: 25.0 ± 20.2, LCa: 7.3 ± 6.0, MCa: 16.1 ± 14.9, PN: 25.4 ± 27.9, T: 18.5 ± 7.9, p = 0.012), a finding also observed in serum MIP-1a levels (TB: 17.1 ± 7.6, LCa: 9.4 ± 7.0, MCa: 28.7 ± 28.7, PN: 33.3 ± 24.0, T: 22.9 ± 8.7, p = 0.003).

Conclusions

Our data suggest that both YKL-40 and MIP-1a, particularly in serum, could prove useful for the differentiation of pleural effusions in clinical practice, especially of TB or LCa origin. However, large-scale studies are needed to validate these findings.

Downregulation of notch signaling pathway in late preterm and term placentas from pregnancies complicated by preeclampsia

Preeclampsia (PE) is a major cause of maternal mortality and morbidity, affecting 3-5% of all pregnancies. The Notch signaling pathway plays an important role during placental development, activating several target genes. Defects in the Notch pathway have adverse effect on placentation. The aim of this study was to investigate the expression of receptors NOTCH1,-2,-3,-4, ligands DLL1,-3,-4, JAG1,-2 and target genes HEY1,-2 in placental tissue samples from 20 late preterm or term pregnancies complicated by PE versus 20 normal pregnancies. mRNA levels of the studied molecules were measured by quantitative Real-Time PCR (qRT-PCR), while the protein expression of the intracellular domain of NOTCH2 (NICD2) and NOTCH3 (NICD3) was measured by Western Blot (WB). qRT-PCR analysis revealed that NOTCH1, NOTCH4 and DLL1 were not expressed in the placenta. On the contrary, NOTCH2, NOTCH3, DLL3, DLL4, JAG1, JAG2, HEY1 and HEY2 mRNA levels were downregulated in PE samples vs. controls (p<0.01). WB confirmed that NICD2 (p = 0.014) and NICD3 (p<0.001) protein levels were also lower in PE specimens. Statistical analysis revealed several significant associations: of NOTCH3 mRNA expression with smoking during pregnancy (p = 0.029), of NICD3 protein levels (p = 0.028) and DLL3 mRNA levels (p = 0.041) with birth weight centile, and of HEY2 transcript levels with parity (p = 0.034) and mode of delivery (p = 0.028). Our results suggest that Notch pathway downregulation is associated with PE. Further studies are required in order to determine the role of these molecules in PE pathogenesis and to evaluate their potential use for the early detection and treatment of PE.

Reduced ANXA5 mRNA and protein expression in pregnancies complicated by preeclampsia

INTRODUCTION

The placental anticoagulant protein Annexin A5 (ANXA5) is a multifunctional protein that is highly expressed on the apical surfaces of syncytiotrophoblasts, and plays an important role in haemostatic regulations, maintaining blood fluidity of the placenta. The aim of this study was to investigate the expression of ANXA5 in pregnancies complicated by preeclampsia (PE).

MATERIALS AND METHODS

Placental tissue samples were collected from 23 pregnancies with PE and 34 normal pregnancies. ANXA5 mRNA levels were measured by quantitative Real-Time PCR (qPCR), while ANXA5 protein expression was measured by Western Blot (WB) and immunohistochemistry.

RESULTS

ANXA5 mRNA expression in PE samples was lower than 1% of its expression in normal samples (mean ± SD: 0.002 ± 0.004 vs. 0.55 ± 0.38, p < 0.001), while ANXA5 protein levels in PE samples were approximately at 65% of the average normal expression (mean ± SD: 0.53 ± 0.30 vs. 0.81 ± 0.25, p=0.001). Immunohistochemical analysis also verified the above results, since PE placentas tended to have low labelling indexes (LIs), in contrast to controls which demonstrated high LIs (p=0.020). Statistical analysis of the WB data revealed that ANXA5 protein expression was increased in PE smokers vs. PE non-smokers (mean ± SD: 0.64 ± 0.23 vs. 0.41 ± 0.33, p=0.027).

CONCLUSIONS

These results suggest that ANXA5 downregulation could be part of the pathophysiology of PE and the possible impairment in coagulation processes, which are seen in pregnancies that demonstrate PE. Further studies may investigate whether ANXA5 could be used as a biomarker for the early detection of PE and for the prediction of its severity.

Molecular profiling of EGFR family in chronic obstructive pulmonary disease: correlation with airway obstruction

BACKGROUND

Growth factors mediate various cellular responses to environmental stimuli. Specifically, exposure of lung epithelium to oxidative stress induced by cigarette smoke stimulates aberrant epidermal growth factor receptor (ERBB) family activation. This study's objective was to evaluate the expression of ERBB1-4 receptors in the lung tissue of smokers with or without chronic obstructive pulmonary disease (COPD).

MATERIALS AND METHODS

ERBBs expression was measured by microarray analysis in lung tissue samples from five patients with COPD and five non-COPD smokers, and by quantitative real-time PCR in additional 20 patients with COPD (GOLD stage II), 15 non-COPD smokers and 10 nonsmoker controls.

RESULTS

Microarray data analysis revealed that ERBB receptors expression was elevated in patients with COPD compared to non-COPD smokers, ranging from 1·62- to 2·45-fold, (P < 0·01). Real-time qPCR verified that patients with COPD had higher ERBB1-3 expression levels compared with non-COPD smokers (PERBB1  < 0·001; PERBB2  = 0·003; PERBB3  = 0·003) and nonsmokers (PERBB1  = 0·019; PERBB2  = 0·005; PERBB3  = 0·011). On the other hand, ERBB4 mRNA levels gradually increased from nonsmokers (0·74 ± 0·19) to non-COPD smokers (1·11 ± 0·05) to patients with COPD (1·57 ± 0·28) and were correlated with the degree of airflow obstruction (PFEV1  < 0·001).

DISCUSSION

These data suggest that ERBB1-3 overexpression is not related only to smoking exposure but probably to epithelial remodelling and mucociliary system distortion, characterizing COPD. Additionally, the inverse correlation of ERBB4 with FEV1 exhibits a possible link between ERBB4 and COPD severity.

Expression of p53 family genes in urinary bladder cancer: correlation with disease aggressiveness and recurrence

p53 is a tumour suppressor gene with an established role in the majority of human neoplasias. Its homologues-p63 and p73-cannot be classified as tumour suppressors, since they encode isoforms with oncogenic properties as well. p63 plays a crucial role in epithelial cell differentiation and p73 is essential for neuronal cell development. The p63 and p73 expressions have been investigated in a variety of human tumours including bladder carcinomas; yet, this is the first study to simultaneously analyse the transcriptional levels of all p53 family members in bladder cancer. Using quantitative real-time polymerase chain reaction, we measured the mRNA expression of p53, p63 and p73 in 30 bladder tumours, each paired with adjacent normal tissue. All three studied genes were up-regulated in malignant specimens, p53 by 1.9-fold, p63 by threefold and p73 by twofold, respectively. Further analysis suggested that p63 and p73 act independently of p53 in the malignant bladder epithelium. Statistical analysis revealed that p63 overexpression was more frequent in recurrent bladder tumours (p = 0.045) and in older patients (p = 0.022). Papillary tumours also exhibited abnormal p63 expression (p = 0.026). Finally, p73 was up-regulated in Grade III one-site tumours (p = 0.040). Our results indicate that all p53 family members are abnormally expressed in bladder cancer but do not act synergistically. High levels of p63 correlate with non-muscle invasive tumours with frequent relapses, whereas p73 overexpression is associated with a more aggressive tumour phenotype.

Heterogeneity of d-glucuronyl C5-epimerase expression and epigenetic regulation in prostate cancer

Heparansulfate proteoglycans (HSPG) play an important role in cell–cell and cell–matrix interactions and signaling, and one of the key enzymes in heparansulfate biosynthesis is d-glucuronyl C5-epimerase (GLCE). A tumor suppressor function has been demonstrated for GLCE in breast and lung carcinogenesis; however, no data are available as to the expression and regulation of the gene in prostate cancer. In this study, decreased GLCE expression was observed in 10% of benign prostate hyperplasia (BPH) tissues and 53% of prostate tumors, and increased GLCE mRNA levels were detected in 49% of BPH tissues and 21% of tumors. Statistical analysis showed a positive correlation between increased GLCE expression and Gleason score, TNM staging, and prostate-specific antigen (PSA) level in the prostate tumors (Pearson correlation coefficients GLCE/Gleason = 0.56, P < 0.05; GLCE/TNM = 0.62, P < 0.05; and GLCE/PSA = 0.88, P < 0.01), suggesting GLCE as a candidate molecular marker for advanced prostate cancer. Immunohistochemical analysis revealed an intratumoral heterogeneity of GLCE protein levels both in BPH and prostate cancer cells, resulting in a mixed population of GLCE-expressing and nonexpressing epithelial cells in vivo. A model experiment on normal (PNT2) and prostate cancer (LNCaP, PC3, DU145) cell lines in vitro showed a 1.5- to 2.5-fold difference in GLCE expression levels between the cancer cell lines and an overall decrease in GLCE expression in cancer cells. Methyl-specific polymerase chain reaction (PCR), bisulfite sequencing, and deoxy-azacytidin (aza-dC) treatment identified differential GLCE promoter methylation (LNCaP 70–72%, PC3 32–35%, DU145, and PNT2 no methylation), which seems to contribute to heterogeneous GLCE expression in prostate tumors. The obtained results reveal the complex deregulation of GLCE expression in prostatic diseases compared with normal prostate tissue and suggest that GLCE may be used as a potential model to study the functional role of intratumor cell heterogeneity in prostate cancer progression.

The molecular mechanisms of intratumour heterogeneity of cancer cells, contributing to tissue malignisation, remain unclear. This study reveals the complex deregulation of d-glucuronyl C5-epimerase (GLCE) expression in benign prostatic hyperplasia and prostate tumours, and the high intratumour heterogeneity of prostate cancer cells in terms of GLCE expression and promoter methylation. The results suggest that GLCE may be used as a potential target gene to study the functional role of cancer cell heterogeneity in disease progression and treatment.

Molecular response of the human diaphragm on different modes of mechanical ventilation

BACKGROUND

The mechanical stress that the human diaphragm is exposed to during mechanical ventilation affects a variety of processes, including signal transduction, gene expression, and angiogenesis.

OBJECTIVES

The study aim was to assess the change in the production of major angiogenic regulators [vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF2), and transforming growth factor beta 1 (TGFB1)] on the human diaphragm before and after contraction/relaxation cycles during mechanical ventilation.

METHODS

This observational study investigates the diaphragmatic mRNA expression of VEGF, FGF2, and TGFB1 in surgical patients receiving general anesthesia with controlled mechanical ventilation (CMV) with muscle relaxation (group A, n = 13), CMV without muscle relaxation (group B, n = 10), and pressure support of spontaneous breathing (group C, n = 9). Diaphragmatic samples were obtained from each patient at two time points: 30 min after the induction of anesthesia (t1) and 90 min after the first specimen collection (t2).

RESULTS

No significant changes in the mRNA expression of VEGF, FGF2, and TGFB1 were documented in groups A and C between time points t1 and t2. In contrast, in group B, the mRNA levels of the above angiogenic factors were increased in time point t2 compared to t1, a finding which was statistically significant (pVEGF = 0.003, pFGF2 = 0.028, pTGFB1 = 0.001).

CONCLUSIONS

These findings suggest that the molecular response of the human diaphragm before and after application of diverse modes of mechanical ventilation is different. Angiogenesis via the expression of VEGF, FGF2, and TGFB1 was only promoted in CMV without muscle relaxation, and this may have important clinical implications.

mRNA expression of G(1)-phase cell cycle regulatory molecules in bladder cancer

PURPOSE

Cell cycle regulation, which is important for normal cellular proliferation, is controlled by a complex network of intracellular proteins, with cyclins, cyclin-dependent kinases (CDKs) and cyclin-dependent kinase inhibitors (CD-KIs) playing a central role. This equilibrium is interrupted in cancer cells, resulting in uncontrolled cellular proliferation.

METHODS

In the present study we examined, by means of semi-quantitative RT-PCR, the expression of G(1)-phase cell cycle regulators MDM2, E2F1, Cyclin D1 (CCND1), CDK4, p19(INK4D), p21(WAF1/CIP1) and p27(KIP1) in a series of 32 bladder cancer specimens paired with adjacent normal tissues.

RESULTS

Cyclin D1 was overexpressed in 10/32 (31.2%) and downregulated in 8/32 (25.0%) bladder cancer specimens. Additionally, p21 was overexpressed in 9/32 (28.1%) and downregulated in 10/32 (31.3%) cancer samples. On the contrary, MDM2, E2F1, CDK4, p19 and p27 expression was normal in the majority of malignant specimens. Further statistical analysis revealed significant associations between increased p21 levels and bladder cancer patients with no exposure to chemicals (p=0.048), as well as with patients with no artificial sweetener intake (p=0.012), and between increased Cyclin D1 levels and study subjects with no artificial sweetener intake (p=0.012).

CONCLUSION

Based on these results, we conclude that Cyclin D1 and p21 mRNA deregulation seems to be an important event in bladder carcinogenesis. However, further studies are needed, in order to determine whether these two cell cycle regulators can be used as markers for the early detection of bladder cancer and to monitor its progression and recurrence.

Reduced placental prolyl hydroxylase 3 mRNA expression in pregnancies affected by fetal growth restriction

OBJECTIVE

To investigate the role of the hypoxia-inducible factor (HIF) pathway in fetal growth restriction (FGR).

DESIGN

A case-control study.

SETTING

Research laboratory and gynaecology clinic.

SAMPLE

Twenty placentas from normal pregnancies and 20 from FGR pregnancies.

METHODS

RNA extraction, cDNA synthesis, quantitative real-time polymerase chain reaction (qRT-PCR) assay, statistical analysis.

MAIN OUTCOME MEASURES

mRNA expression of HIF-1α, HIF-2α and HIF-β (ARNT), along with prolyl hydroxylase domain 3 (PHD3), which leads to proteasomal degradation of HIF-α subunits.

RESULTS

No statistically significant differences in the transcription levels of ARNT and HIF-2α were found between FGR and normal placentas. By contrast, PHD3 and HIF-1α mRNA were downregulated in FGR placentas. PHD3 mRNA expression was associated with gestational age at delivery (P = 0.008), birthweight centile (P = 0.029) and abnormal umbilical artery (UA) Doppler measurements (P = 0.034).

CONCLUSIONS

As PHD3 regulates the HIF-mediated hypoxic response in FGR, we deduce that fetal adaptation to hypoxia ranges from impaired to adequate, as observed by the gradient of PHD3 downregulation in relation to the severity of FGR.

Deregulation of apoptosis mediators' p53 and bcl2 in lung tissue of COPD patients

Abnormal apoptotic events in chronic obstructive pulmonary disease (COPD) subvert cellular homeostasis and may play a primary role in its pathogenesis. However, studies in human subjects are limited.

p53 and bcl2 protein expression was measured by western blot on lung tissue specimens from 43 subjects (23 COPD smokers and 20 non-COPD smokers), using beta-actin as internal control. Additionally, p53 and bcl2 expression patterns were evaluated by immunohistochemistry in formalin-fixed, paraffin-embedded lung tissue sections from the same individuals.

Western blot analysis showed statistically significant increased p53 protein levels in COPD smokers in comparison with non-COPD smokers (p = 0.038), while bcl2 protein levels were not statistically different between the two groups. Lung immunohistochemistry showed increased ratio of positive p53-stained type II pneumocytes/total type II pneumocytes in COPD smokers compared to non-COPD smokers (p = 0.01), whereas the p53 staining ratio in alveolar macrophages and in lymphocyte-like cells did not differ statistically between the two groups. On the other hand, bcl2 expression did not differ between the two groups in all three cell types.

The increased expression of pro-apoptotic p53 in type II pneumocytes of COPD patients not counterbalanced by the anti-apoptotic bcl2 could reflect increased apoptosis in the alveolar epithelium of COPD patients. Our results confirm previous experiments and support the hypothesis of a disturbance in the balance between the pro- and anti-apoptotic mediators in COPD.

YY1 Over-expression in human brain gliomas and meningiomas correlates with TGF-beta1, IGF-1 and FGF-2 mRNA levels

In this study we examined by QRT-PCR the mRNA expression of TGF-beta 1, IGF-1, EGF, FGF-2 and YY1 in human brain tumors. Our findings introduce YY1, for the first time, as a novel gene implicated in brain gliomatogenesis and meningioma establishment. We present a positive correlation between the autocrine expression of YY1 and TGF-beta 1, IGF-1 and FGF-2, known to be involved in the progression of gliomas and meningiomas. We suggest that mRNA profiling of the above genes in the early stages of disease development could be useful for prognostic purposes, and these genes can be considered as potential targets for therapeutic approaches against brain tumors.

Expression analysis of peptide growth factors VEGF, FGF2, TGFB1, EGF and IGF1 in prostate cancer and benign prostatic hyperplasia

Peptide growth factors play an important role in several intracellular processes, such as cellular growth and differentiation, angiogenesis and apoptosis, as well as in carcinogenesis, since they contribute significantly to the malignant transformation. The prostate gland is abundant in growth factors. The two most known prostatic diseases, prostate cancer (PCa) and benign prostatic hyperplasia (BPH), are among the most common diseases that affect elderly men. This study was conducted using a quantitative real-time RT-PCR method in order to determine mRNA expression levels of peptide growth factors VEGF, FGF2, TGFB1, EGF, and IGF1 in tissue specimens from 42 patients with PCa, 42 with BPH, and 10 normal prostate samples obtained post-mortem from young individuals, in order to examine their association with prostatic hyperplasia and neoplasia. Our results show that in PCa, growth factors VEGF, EGF and FGF2 are overexpressed, while TGFB1 and IGF1 have reduced mRNA levels. In BPH, transcript levels of FGF2 and EGF are normal, while VEGF, TGFB1 and IGF1 exhibit downregulation. Further statistical analysis revealed that PCa patients with high levels of PSA blood levels have decreased FGF2 expression (p=0.016). Additionally, cancer patients with low Gleason score (<7) have increased EGF (p=0.035) and IGF1 (p=0.031) mRNA levels. IGF1 levels are also elevated in tumors with TNM stages T1-T2 (p=0.030). In BPH, older patients have reduced EGF expression (p=0.018), while IGF1 is overexpressed in younger patients (p=0.041). Additionally, the co-expression pattern of the five studied growth factors differs significantly among normal, benign and malignant prostate. These results implicate VEGF, FGF2, TGFB1, EGF and IGF1 in the development of both PCa and BPH, rendering them potential targets for disease detection, monitoring and therapy.

Aberrant methylation and deacetylation of deleted in liver cancer-1 gene in prostate cancer: potential clinical applications

PURPOSE

The deleted in liver cancer-1 (DLC-1) gene that encodes a Rho GTPase-activating protein with tumor suppressor function is located on chromosome 8p21-22, a region frequently deleted in prostate carcinomas. This study was designed to determine whether DLC-1 is deregulated in prostate carcinomas and to assess the contribution of DLC-1 alterations to prostate carcinogenesis.

EXPERIMENTAL DESIGN

Primary prostate carcinomas, prostate carcinoma cell lines, benign prostatic hyperplasias, and normal prostatic tissues were examined for detection of functional and structural alterations of the DLC-1 gene by real-time PCR, methylation-specific PCR, and Southern and Western blots.

RESULTS

Down-regulation or loss of DCL-1 mRNA expression was detected in 10 of 27 (37%) prostate carcinomas, 3 of 5 (60%) prostate carcinoma cell lines, and 5 of 21 (24%) benign prostatic hyperplasias. DLC-1 promoter methylation was identified in 13 of 27 (48%) prostate carcinomas and 2 matching normal tissues and in 15 of 21 (71%) benign prostatic hyperplasias but was absent in 10 normal prostatic tissues from noncancerous individuals. Genomic deletions were found in only 3 prostate carcinomas and 1 benign prostatic hyperplasia. DLC-1 protein was not detected in 8 of 27 (30%) prostate carcinomas and 11 of 21 (52%) benign prostatic hyperplasias. Methylation of DLC-1 correlated with age in prostate carcinoma patients (P = 0.006) and with prostate-specific antigen blood levels in benign prostatic hyperplasia patients (P = 0.029). Treatment of the three prostate carcinoma cell lines (PC-3, LNCaP, and 22Rv1) expressing a low level of DLC-1 transcripts with inhibitors of DNA methyltransferase or histone deacetylase increased DLC-1 expression.

CONCLUSIONS

These results show that the transcriptional silencing of DLC-1 by two epigenetic mechanisms is common and may be involved in the pathogenesis of prostate carcinomas and benign prostatic hyperplasias and could have potential clinical application in the early detection and gene therapy of prostate cancer.

Deregulation of p73 isoform equilibrium in benign prostate hyperplasia and prostate cancer

p73, a p53 homologue important for growth suppression, differentiation and induction of apoptosis, utilizes different promoters and undergoes alternative splicing to produce several isoforms differing in their ability to overlap p53 functions. Using reverse transcriptase-polymerase chain reaction (RT-PCR) to assess the mRNA levels of p53, p73 (total and isoforms specific for exons 2 and 13), MDM2, CDKN1A and beta2-microglobulin as internal control, we analyzed 35 prostate carcinomas and 44 benign prostate hyperplasias (BPH) compared to 14 normal prostates. Shift of p73 isoform mRNA levels from exon 13 lacking to exon 13 containing copies was observed in 80% of prostate cancer cases and in 52.3% of BPH specimens, and from exon 2 containing to exon 2 lacking (p73Deltaexon2) transcripts in 45.7% of cancer cases, but only in 9.1% of BPH samples. From these findings we deduce that p73 isoform balance is disrupted in prostate cancer and BPH, suggesting that this disequilibrium could play an important role in both prostate hyperplasia and malignancy.

Association of p53 codon 72 polymorphism with advanced lung cancer: the Arg allele is preferentially retained in tumours arising in Arg/Pro germline heterozygotes

The association of p53 codon 72 polymorphism with cancer has been investigated by several scientific groups with controversial results. In the present study, we examined the genotypic frequency of this polymorphism in 54 patients with advanced lung cancer and 99 normal controls from the geographical region of Greece. Sputum and bronchial washing samples from each patient were assayed for the presence of human papillomavirus. Codon 72 heterozygous (Arg/Pro) patients were also analysed for loss of heterozygosity at the TP53 locus, in order to determine the lost p53 allele (Arg or Pro). p53 Arg/Arg genotype was significantly increased in lung cancer patients compared to normal controls (50% vs 24.2%, P<0.002). Human papillomavirus was detected only in two patients (3.7%). Loss of heterozygosity at the TP53 locus was found in 14 out of 27 Arg/Pro patients (51.85%). The Pro allele was lost in 11 cases (78.6%), while the Arg allele was lost in three (21.4%). Our results suggest that p53 codon 72 Arg homozygosity is associated with advanced lung cancer, and that the Arg allele is preferentially retained in patients heterozygous for this polymorphism. On the other hand, human papillomavirus infection does not seem to play an important role in lung carcinogenesis.

p53 codon 72 polymorphism and its association with bladder cancer

p53 codon 72 Arg homozygosity has been associated with increased risk of developing cervical cancer. This association has been tested in various human cancers with controversial results. In the present study we investigated the impact of this polymorphism in a population-based case-control study of bladder cancer. Using allele-specific polymerase chain reaction to detect the p53 codon 72 polymorphism, we tested peripheral blood samples from 50 patients with bladder cancer and 99 healthy individuals of similar age and from the same geographical region. Tumor specimens from all bladder cancer patients were examined for the presence of human papilloma virus (HPV). The distribution of p53 alleles in bladder cancer patients and in controls was statistically significant (P<0.002; odds ratio, 2.67; 95% confidence interval, 1.38-5.20), and homozygosity for arginine at residue 72 was associated with an increased risk for bladder cancer (P<0.00002; odds ratio, 4.69; 95% confidence interval, 2.13-10.41). The presence of HPV was found in six of the 50 patients (12%). This is the first study correlating p53 codon 72 polymorphism with bladder cancer. Our results provide evidence that this p53 polymorphism is implicated in bladder carcinogenesis and that individuals harboring the Arg/Arg genotype have an increased risk of developing bladder cancer.