Impact of TP53 codon 72 and MDM2 promoter 309 allelic dosage in a Moroccan population with hepatocellular carcinoma.

Single-nucleotide polymorphisms (SNPs) in codon 72 of the TP53 gene (rs1042522) and in the promoter region of the MDM2 gene (SNP309; rs2279744) have been shown to play a role in the predisposition to many cancers. However, these findings were inconsistent in other tumor types, and ethnicity is suspected to be a critical factor influencing the effects of these SNPs on the cancer risk. The aim of the present study was to investigate whether these functional SNPs were associated with an enhanced risk of liver tumorigenesis in Moroccan patients. We have genotyped both polymorphisms in 96 patients with hepatocellular carcinoma (HCC) and 222 controls without HCC matched for age, gender and ethnicity by PCR-RFLP confirmed by sequencing. A joint effect between the MDM2 and TP53 polymorphisms and an increased risk of liver cancer was detected, with the odds ratio for the presence of both MDM2 309GG and TP53 72Pro/Pro genotypes being 10 (95% confidence interval 0.39-255.55). Interestingly, a significant increase in the HCC risk was observed when at least two deleterious alleles were present, indicating an allele dosage effect. There was no evidence for any association with early age of HCC onset when deleterious alleles of MDM2 SNP309 and TP53 Arg72Pro where present. Our findings suggest that the combination of TP53 72Pro and MDM2 309G polymorphisms enhance the risk of developing HCC. These results deserve further confirmation in other populations.

Influence of mutation of the HFE gene on the progression of chronic viral hepatitis B and C in Moroccan patients.

The implication of hemochromatosis (HFE) gene mutations in chronic viral hepatitis remains controversial. The aim of the present study was to measure the frequencies of the common HFE gene mutations in Moroccan subjects with chronic viral hepatitis B and C and to assess their influence on the progression of liver disease. H63D and C282Y mutations were screened by the polymerase chain reaction followed by restriction fragment length polymorphism analysis in 170 chronic hepatitis B patients, 168 chronic hepatitis C patients, and 200 healthy controls. A very small proportion of patients infected with hepatitis B virus (HBV) or hepatitis C virus (HCV; 1.8% and none, respectively) were heterozygous for the C282Y mutation, that is, rates not statistically different from those observed in healthy control (2%, P > 0.05). Similarly, the frequency of the H63D allele was not significantly different between HBV (13.8%) or HCV (14.3%) patients and controls (13.5%, P > 0.05). Multivariate analysis showed that carriers of the H63D mutation infected with HBV are at higher risk to progress towards an advanced liver disease when compared with patients infected with HBV with wild-type (OR = 2.45, 95% CI = 1.07-5.58). In contrast, no association between HFE mutated HCV-infected patients and an increased risk of disease progression was found (OR = 1.24, 95% CI = 0.61-2.50, P = 0.547). In conclusion, in Morocco the frequency of the HFE C282Y allele is very low and H63D mutation carriage occurs in almost 14% of the patients, a rate similar in chronic hepatitis patients and healthy controls. In the case of chronic hepatitis B, the carriage of the H63D variant represents a risk factor of evolution towards a more active disease.

Adult colocolic intussusception diagnosed by ultrasonography: a case report.

INTRODUCTION: Intussusception is highly uncommon in adults and accounts for only 5% of all reported cases. It is more commonly secondary to an identifiable bowel lesion in 90% of cases, whereas 10% have no discernable cause. Diagnosis is difficult due to non-specific symptoms of the disease. Diagnostic imaging plays an important role in the diagnosis of the condition. Sonography and computed tomography are the most commonly used imaging techniques. In adults, intussusception usually requires treatment by surgical resection of the affected bowel. CASE PRESENTATION: A 35-year-old Moroccan woman presented with a five-month history of intermittent abdominal pain and one episode of bleeding from the rectum. At physical examination an abdominal mass was noted. Abdominal sonography revealed a 6.3 × 8.5 cm midline mass in her upper abdomen that was tender. In transverse section, the mass had the multiple concentric rings of hypoechoic and echogenic layers associated with the sonographic appearance of intussusception. In longitudinal section, the mass had the sonographic aspect of multiple parallel lines, giving the so-called "sandwich appearance".A corresponding contrast-enhanced abdominal computed tomography scan also demonstrated the intussusception. Surgery confirmed a colocolic intussusception with a large, firm, indurated mass as the lead point. A right hemicolectomy was undertaken because of concern about possible malignancy. The resected ascending colon was then opened up, to find a protruding tumor of the ascending colon that was acting as the lead point. It measured 7.6 × 6.9 × 2.4 cm. Pathology diagnosed an infiltrating, differentiated adenocarcinoma of the ascending colon invading through the muscularis propria. No lymphovascular invasion was seen. Our patient has recovered well. CONCLUSION: Intussusception is relatively rare in the adult population, and this, along with the vague clinical features, makes diagnosis difficult. Ultrasonography and computed tomography have been proven to be effective diagnostic modalities. Ultrasonography can be performed quickly and accurately, and is widely available. In adults, intussusception is usually associated with an underlying cause and requires treatment by surgical resection.

Polymorphisms in antioxidant defence genes and susceptibility to hepatocellular carcinoma in a Moroccan population.

Reactive oxygen species have been related to the aetiology of cancer as they are known to be mitogenic and therefore capable of tumour promotion. The aim of this study was to assess the role of common variation in three polymorphic genes (MnSOD Ala-9Val, GPX1 Pro198Leu and CAT -262 C > T) coding for antioxidant defence enzymes in modulating individual susceptibility to hepatocellular carcinoma (HCC) using a case-control study (cases = 96 and controls = 222). PCR-RFLP and sequencing methods were used to determine the genotype. Overall, there were no associations between genotypes GPX1 and HCC risk (OR, 1.16; 95% CI, 0.56-2.42; p = 0.685). The MnSOD Ala/Ala and CAT TT genotypes were more frequent in HCC than in control (p = 0.001 and p = 0.072, respectively). Further analyses stratified by gender or HCV infection revealed that men and HCV-infected patients carrying CAT TT genotype had a higher risk to develop HCC when compared with controls (OR = 15.94; 95% CI, 3.48-72.92; p < 0.000001 and 12.01; 95% CI, 0.64-223.63, p = 0.056, respectively). Combined MnSOD Ala/Ala and GPx1 Leu/Leu had a synergistic effect on HCC risk, with an OR of 3.84 (p = 0.029). Furthermore an even more pronounced risk was observed when we combined MnSOD Ala/Ala and CAT TT (OR = 13.60, p = 0.023). It appears that variants in MnSOD, CAT or GPX1 have an influence on HCC risk in this cohort. Furthermore, it is possible that cumulative defects in protection from oxidative stress may result in increased risk of liver cancer in the Moroccan population.

Single nucleotide polymorphism in DNMT3B promoter and its association with hepatocellular carcinoma in a Moroccan population.

Hepatocellular carcinoma is a major malignant tumor characterized in all areas by the disparity of risk between genders. The molecular bases of such disparity are still poorly understood. DNA-methyltransferase-3B (DNMT3B) may play an oncogenic role during tumorigenesis, and its genetic variants have been consistently associated with risk of several cancers, but a single study has investigated their roles in hepatocellular carcinoma (HCC). Polymorphisms of the DNMT3B gene may influence its activity on DNA methylation in several cancers, thereby modulating susceptibility to tumorigenesis. To test this hypothesis, we investigated the association between single nucleotide polymorphism -149C>T (rs2424913) in the promoter region DNMT3B and risk of HCC in a Moroccan population. In this case-control study, the DNMT3B SNP was genotyped by polymerase chain reaction-restriction fragment length polymorphism in 96 HCCs patients and 222 healthy controls that matched for age, sex and ethnicity. Overall, we found that, the DNMT3B 149 TT genotype was not significantly associated with increased risk of HCC (adjusted odds ratio (OR), 0.86, 95% CI, 0.41-1.80, P=0.697). Stratification analysis detected, however, a trend towards a profound risk in the female subset of patients (OR=2.04, 95% CI, 0.77-5.42) and a lesser risk for HCV-infected patients (OR=1.33, 95% CI, 0.43-4.17). Our findings contrast with those of previous studies performed in various cancers, which showed that individuals carrying at least one T allele have a significantly increased risk of developing cancer. In addition, we provide genetic evidence for the major difference of HCC risk between men and women. Further mechanistic studies are needed to unravel the underlying molecular mechanisms.

MDM2 SNP309T>G polymorphism and risk of hepatocellular carcinoma: a case-control analysis in a Moroccan population.

BACKGROUND: The Murine double minute 2 (MDM2) gene encodes a negative regulator of the p53 tumor suppressor protein. A single nucleotide polymorphism (SNP) in the MDM2 promoter (a T to G exchange at nucleotide 309) has been reported to produce accelerated tumor formation. The aim of this study was to investigate whether this functional SNP is associated with an enhanced risk of liver tumorigenesis in Moroccan patients. METHODS: The study consisted in the comparison of 96 hepatocellular carcinomas (HCC) cases and 222 controls without HCC matched for age, gender and ethnicity. PCR-RFLP and sequencing methods were used to determine the genotype at the MDM2 SNP309T>G locus. RESULTS: Overall, our results indicate that the GG genotype of SNP309 is significantly associated with an increased risk of HCC (odds ratio, OR=2.60, 95% CI, 1.08-6.28). Interestingly, despite a wide range of confidence interval, there is a trend associating the GG genotype with a high risk of HCC in males (OR=3.31; 95% CI, 0.93-11.82) and in HCV-infected patients (OR=3.7; 95% CI, 0.82-16.45). By contrast, no association between age at diagnosis and MDM2 SNP309 genotypes was observed in HCC patients (P=0.610). CONCLUSION: Our findings suggest that the MDM2 309T>G polymorphism is an important modulator of hepatocellular carcinoma development in Moroccan patients.

Prevalence of common HFE and SERPINA1 mutations in patients with hepatocellular carcinoma in a Moroccan population.

BACKGROUND: Hereditary hemochromatosis and SERPINA1 mutation were reported to affect liver functions. Our objective was to estimate the prevalence of HFE and SERPINA1 (formerly known as alpha1-antitrypsin, AAT) mutations and assess their influence on hepatocellular carcinoma development. METHODS: This study included 222 controls and 96 cases with hepatocellular carcinoma. PCR-RFLP was used to characterize S and Z alleles in SERPINA1, as well as C282Y/H63D alleles of HFE. RESULTS: In healthy subjects and hepatocellular carcinoma patients as well, no homozygotes for the C282Y mutation were found. In controls, heterozygosity and homozygosity for the H63D mutation were 27 and 0.9%, respectively. Among patients, homozygosity for the H63D mutation was 3.1%, whereas heterozygosity for C282Y and H63D was 2.1 and 35.4%, respectively. Interestingly, albeit it does not reach significance (p=0.062), H63D was more prevalent in hepatocellular carcinoma patients than in controls (38.5 vs. 27.9%, respectively). The association was stronger when considering only male patients with hepatocellular carcinoma (47.1 vs. 23.6, p=0.001). Allele frequencies of S and Z in controls were 0.45% (95% CI=0.2-1.07) and 0.22% (95% CI=0.2-0.6), respectively, and 1 for S and 0% for Z in HCC. No significant difference was found between cases and controls. CONCLUSIONS: We provide a novel appraisal of HFE and SERPINA1 mutations prevalence in the Moroccan population. Results are consistent with the worldwide spread of the H63D and S mutation and the north European restriction of the C282Y and Z. Our results show that H63D carriage is increased among hepatocellular carcinoma patients, suggesting that it may confer an increased susceptibility to hepatocellular carcinoma even in a heterozygous state. On the contrary, HFE C282Y and SERPINA1 mutations do not contribute to hepatocellular carcinoma development.

Genetic polymorphism in the manganese superoxide dismutase gene is associated with an increased risk for hepatocellular carcinoma in HCV-infected Moroccan patients.

Hepatocellular carcinoma (HCC) ranks among the 10 most common cancers worldwide. The main risk factors for its development are hepatitis B and C virus infections. Hepatitis B and C viruses induce chronic inflammation and oxidative stress that could predispose a cell to mutagenesis and proliferation. Manganese superoxide dismutase (MnSOD) catalyses the detoxification of free radicals, thus playing a crucial role in the protection against damage. A valine (Val) to alanine (Ala) substitution at amino acid 9, mapping within the mitochondrion-targeting sequence of the MnSOD gene, has been associated with an increased cancer risk. The aim of our study was to investigate a possible association of the Val/Ala-MnSOD polymorphism and HCC development in Moroccan patients. Genotypes were determined by means of PCR and RFLP analysis in 96 patients with HCC and 222 control subjects matched for age, sex, and ethnicity. Homozygous Ala/Ala carriers were 31% in the cases and 18% in the controls, which corresponds to an odds ratio (OR) of 2.89, with a 95% confidence interval (CI) of 1.47-5.68. Stratification into subgroups based on HCV infection status revealed an even more increased risk for homozygous Ala/Ala carriers with hepatitis C infection (38.2% in the cases versus 14.8% in the control subjects OR, 5.09; 95% CI, 1.76-14.66). Our findings provide further evidence of an association between the Ala-9Val MnSOD polymorphism and HCC occurrence in hepatitis C virus-infected Moroccan patients.

The Pro variant of the p53 codon 72 polymorphism is associated with hepatocellular carcinoma in Moroccan population.

AIM: Codon 72 polymorphism of the p53 gene has been implicated in cancer risk, and it has been suggested that it may have an impact on the clinical outcome of the disease. Our objective was to evaluate the association between p53 polymorphism at codon 72 and hepatocellular carcinoma (HCC) in the Moroccan population. METHODS: Genomic DNA was extracted from peripheral blood cells of 96 patients with HCC and 222 controls without HCC matched for age, gender and ethnicity. Codon 72 polymorphism of p53 was identified by PCR-restriction fragment length polymorphism, confirmed by sequencing. RESULTS: Patients with HCC had higher frequencies of Pro/Pro (13.5% vs. 6.3%, P < 0.02) than controls and consequently a 2.3-fold increased risk of liver cancer development (odds ratio [OR], 2.304; 95% confidence interval [CI], 1.014-5.234). In addition, we found a significant association between the p53Arg72Pro polymorphism and the female gender in HCC. Men with Pro/Pro genotype had a 1.57-fold increased risk for HCC, whereas the corresponding genotype in women had a 4.4-fold increased risk of HCC (OR, 4.4; 95% CI, 1.18-16.42). No correlation between the polymorphism and HCC risk was found when comparing the hepatitis C virus (HCV)-positive cases to HCV-positive controls. However, HCV-negative subjects and Pro/Pro genotype had a 3.31-fold increased risk for HCC. CONCLUSION: These results provide evidence that p53 polymorphism at codon 72 is a modifier of hepatocarcinogenesis, especially in women and HCV-negative subjects.

[Advances in the diagnosis and management of gastrointestinal tumours: 5 cases]. / Nouvelles acquisitions diagnostiques et thérapeutiques sur les tumeurs stromales digestives: à propos de cinq cas.

INTRODUCTION: Gastrointestinal stromal tumours (GIST) are the most frequent mesenchymatous tumours of the digestive tract. Options for diagnosis and treatment have developed rapidly in recent years. The authors report five cases of GIST. CASES: The study concerns 5 patients: 3 men and 2 women, with a mean age at diagnosis of 39.8 years. We describe the circumstances of discovery and the clinical and morphological characteristics of these tumours. They were located in the oesophagus (1 case), stomach (2 cases), small intestine (1 case) and mesentery (1 case). Tumour size ranged from 4-20 cm. Liver metastasis was identified at initial diagnosis for one patient. Immunohistochemical analysis identified expression of CD34, CD117 and S-100 proteins in all cases and smooth muscle actin in 2 cases. All the patients underwent surgical resection for GIST, and one received chemotherapy. No patient received imatinib treatment. After a mean follow-up of 40 months: one patient presented peritoneal carcinosis at one year, and 3 patients liver metastasis at 2 years; one of the latter died. DISCUSSION: The cases reported here are original by the rarity of their localization (especially the oesophagus and the mesentery). Diagnosis and treatment options for patients are described in a discussion of the recent advances in the field. CONCLUSION: GIST are the most frequently mesenchymatous tumours of the digestive tract. They must be recognized, especially in view of their frequency. Optimal management today involves complete tumour resection and imatinib.