Detection of methylation in the CpG islands of the RASSF1A and RAR2b gene promoters in breast cancer (BC)

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Background: Aberrant methylation of CpG islands of cancer-related genes has emerged as an important epigenetic mechanism during carcinogenesis. We examined the methylation of RASSF1A (Ras-association domain family 1, isoform A) and RAR2b (Retinoic Acid Receptor 2b) genes in BC. The knowledge of their role in BC is limited and confused to date. Methods: Promoter methylation was measured in 37 pts, 26 with BC and 11 with benign lesions. The specimens were obtained from archive formalin-fixed paraffin-embedded tumors. After DNA extraction, the methylation was determined by chemical modification of DNA with sodium bisulfite and subsequent double “hot start” Methylation-Specific PCR (MSP), followed by detection on agarose gel. Results: Methylation of at least one of the genes was observed in 18/26 pts (p<0.05). Methylation of RASSF1A gene was observed in 15/26 and RAR2b in 11/26 pts. Both genes were methylated in 8/26 pts. Correlation between methylation and clinicopathological features revealed an association of the RASSF1A gene with T2 tumors (12/15 pts, p<0.05) and ER (+) status (12/15 pts, p<0.05). T2 tumors and ER (+) status presented together in 9/15 pts. The methylation of RAR2b gene was not associated with any known clinicopathological features. In benign lesions methylation of at least one of the genes was observed in 8/11 pts (p<0.05). Methylation of RASSF1A gene was observed in 5/11 pts and RAR2b in 7/11 pts. Both genes were methylated in 4/11 pts. Conclusions: Both genes are frequently methylated in both benign and malignant breast lesions. The association of methylation of RASSF1A gene with tumor size and ER status is noteworthy. The small number of pts does not allow us to confirm the exact role of gene methylation in BC yet. Larger studies are required in order to assess if these epigenetic alterations point out new BC markers, which could be helpful for BC control.

No significant financial relationships to disclose.

Detection of methylation in the CpG islands of the p16INK4A, RASSF 1A and methylguanine methyltransferase gene promoters in pancreatic adenocarcinoma

Pancreatic cancer consists of an accumulation of genetic and epigenetic alterations. Recently, aberrant methylation of CpG islands of cancer-related genes has emerged as an important epigenetic mechanism of their transcriptional dysregulation during tumour development [1]. Therefore, new diagnostic methods, for early detection based on a better understanding of the molecular biology of pancreatic cancer, are required. We examined the methylation status of p^16INK4A, RASSF 1A and methylguanine methyltransferase (MGMT) genes considered to be inactivated by promoter methylation in several tumours.

The p^16INK4A is an important G1/S cell cycle regulator gene [2]. RASSF 1A gene is involved in apoptotic signalling, microtubule stabilization and cell cycle progression [3]. The MGMT gene removes mutagenic and cytotoxic alkyl-adducts from the O6-position of guanine in DNA. Hypermethylation of the gene leads to the inactivation of DNA repair and to microsatellite instability [4].

To date, little is known about the exact role of hypermethylation of these genes in pancreatic adenocarcinoma, as the molecular mechanisms underlying these neoplasms remain poorly understood.

Evidence for the ''paradox'' association between hypertensive lower esophageal sphincter and gastroesophageal reflux disease

There are several studies suggesting the paradoxical simultaneous presence of hypertensive lower oesophageal sphincter and gastroesophageal reflux disease. We present a case of a 22-year-old male patient who was examined in our outpatient clinic with oesophageal food bolus impaction during a meal, severe chest pain and drooling. Manometry revealed a hypertensive lower esophageal sphincter pressure (resting pressure 35 mmHg) and pHmetry revealed a DeMeester score > 14.72 (43.27). Six months after therapy with lansoprazole, manometry revealed a normal lower oesophageal sphincter (resting pressure 14 mmHg) and the DeMeester score was < 14.72 (5.89). The patient is now asymptomatic. This report is the only published case which exhibits the normalization of lower oesophageal pressure 6 months after gastroesophageal reflux disease management with lansoprazole, thus proving and establishing the above ''paradox''.

Synchronous occurrence of a primary colon adenocarcinoma and a gastric stromal tumor. A case report

Gastrointestinal stromal tumors are currently the object of a great clinical and experimental interest. We are presenting the case of a 69-year-old patient, who was presented with lower gastrointestinal bleeding and dyspeptic symptoms over the last six months. The colonoscopy showed a large tumor of the sigmoid and the gastroscopy a large gastric tumor of the antrum, which were histologically diagnosed as colonic adenocarcinoma and gastric stromal tumor respectively. The patient underwent a sigmoidectomy and a partial gastrectomy. Six months after surgery were the clinical condition, abdominal CT, gastroscopy and colonoscopy without pathological findings. To our best knowledge, this is the second report of a synchronous gastric stromal tumor and a colonic adenocarcinoma in medical literature.

Inflammatory fibroid polyp or Vanek's tumour

We report a case of a 65-year-old woman who presented with recurrent episodes of severe, postprandial abdominal pain followed by projectile vomiting. Gastroscopy revealed a large polyp in the prepyloric region. During peristalsis, the polyp was repeatedly 'passing' through the pylorus into the duodenal bulb, hence obstructing the lumen. The polyp was eventually removed in a piecemeal fashion. Histopathologic examination revealed an inflammatory fibroid polyp (known also as Vanek's tumour). A brief review on inflammatory fibroid polyps follows.

Tannenbaum and metal stents in the palliative treatment of malignant distal bile duct obstruction: a comparative study of patency and cost effectiveness

BACKGROUND

Stent clogging is the major limitation of palliative treatment for malignant biliary obstruction. Metal stents have much better patency than plastic stents, but are more expensive. Preliminary data suggest that the recently designed plastic (Tannenbaum) stent has better duration of patency than the polyethylene stent. This study aimed to compare the efficacy and cost effectiveness between the Tannenbaum stent without side holes and the uncovered metal stent for patients with malignant distal common bile duct obstruction.

METHODS

In this study, 47 patients (median age, 73 years, range, 56-86 years) with inoperable malignant distal common bile duct strictures were prospectively randomized to receive either a Tannenbaum stent (n = 24) or an uncovered self-expandable metal stent (n = 23). The patients were clinically evaluated, and biochemical tests were analyzed if necessary until their death or surgery for gastric outlet obstruction. Cumulative first stent patency and patient survival were compared between the two groups. Cost-effectiveness analysis also was performed for the two study groups.

RESULTS

The two groups were comparable in terms of age, gender, and diagnosis. The median first stent patency was longer in the metal group than in the Tannenbaum stent group (255 vs 123.5 days; p = 0.002). There was no significant difference in survival between the two groups. The total cost associated with the Tannenbaum stents was lower than for the metal stents (17,700 vs 30,100 euros; p = 0.001), especially for patients with liver metastases (3,000 vs 6,900 euros; p < 0.001).

CONCLUSIONS

Metal stent placement is an effective treatment for inoperable malignant distal common bile duct obstruction, but Tannenbaum stent placement is a cost-saving strategy, as compared with metal stent placement, especially for patients with liver metastases and expected short survival time.