Randomized phase III clinical trial comparing the combination of capecitabine and oxaliplatin (CAPOX) with the combination of 5-fluorouracil, leucovorin and oxaliplatin (modified FOLFOX6) as adjuvant therapy in patients with operated high-risk stage II or stage III colorectal cancer.

BACKGROUND: The aim of the trial was to compare two active adjuvant chemotherapy regimens in patients with early stage colorectal cancer (CRC). METHODS: Patients were assigned to oxaliplatin, leucovorin and 5-FU for 12 cycles (group A, FOLFOX6) or oxaliplatin and capecitabine for eight cycles (group B, CAPOX). Primary endpoint was disease-free survival (DFS). Tumors were classified as mismatch repair proficient (pMMR) or deficient (dMMR) according to MLH1, PMS2, MSH2 and MSH6 protein expression. KRAS exon two and BRAF V600E mutational status were also assessed. RESULTS: Between 2005 and 2008, 441 patients were enrolled, with 408 patients being eligible. After a median follow-up of 74.7 months, 3-year DFS was 79.8 % (95 % CI 76.5-83.4) in the FOLFOX group and 79.5 % (95 % CI 75.9-83.1) in the CAPOX group (p = 0.78). Three-year OS was 87.2 % (95 % CI 84.1-91.1) in the FOLFOX and 86.9 % (95 % CI 83.4-89.9) in the CAPOX group (p = 0.84). Among 306 available tumors, 11.0 % were dMMR, 34.0 % KRAS mutant and 4.9 % BRAF mutant. Multivariate analysis showed that primary site in the left colon, earlier TNM stage and the presence of anemia at diagnosis were associated with better DFS and overall survival (OS), while grade one-two tumors were associated with better OS. Finally, a statistically significant interaction was detected between the primary site and MMR status (p = 0.010), while KRAS mutated tumors were associated with shorter DFS. However, the sample was too small for safe conclusions. CONCLUSIONS: No significant differences were observed in the efficacy of FOLFOX versus CAPOX as adjuvant treatment in high-risk stage II or stage III CRC patients, but definitive conclusions cannot be drawn because of the small sample size. TRIAL REGISTRATION: ANZCTR 12610000509066 . Date of Registration: June 21, 2010.

The prognostic role of preoperative serum CA 125 levels in patients with endometrial carcinoma.

PURPOSE: Previous studies have shown that elevated preoperative serum CA 125 levels strongly correlate with various clinical and pathological variables and prognosis of patients with endometrial carcinoma (EC). The aim of the present study was to evaluate the clinical significance of preoperative serum CA 125 levels in patients with EC. METHODS: A retrospective study of all EC patients treated at our institution between 1995 and 2010 with available follow-up was conducted. The preoperative serum level of CA 125 was measured in 99 patients and evaluated in relation to various clinical and pathological variables and outcome. We used the cut-off level of 20 U/ml for CA 125 on chi-square test for categorical variables. Survival analysis was performed with the use of Kaplan Meier method, the log rank test and Cox proportional hazards regression analysis. RESULTS: In the early stages of disease the mean values of CA 125 were 35 U/ml (SD±70) for stages IA-IB and 21 U/ml (SD±29) for stage IC (Mann-Whitney test for continuous variables). In advanced stages of disease (III-IV), the values of preoperative serum CA 125 levels were statistically increased, with mean value 54 U/ml (SD±44), in comparison to stages IA-IB (p=0.02) and IC (p=0.007). According to the multivariate analysis, elevated preoperative serum CA 125 level (p=0.043) and histological tumor type (p=0.004) were independent prognostic factors for disease free survival (DFS) and overall survival (OS) of patients with EC. CONCLUSION: The current study suggests that measurement of preoperative serum CA 125 is a useful clinical tool in the prognosis of patients with EC.

Intestinal mucosal proliferation, apoptosis and oxidative stress in patients with liver cirrhosis.

BACKGROUND: Intestinal mucosal barrier dysfunction in liver cirrhosis and its implicated mechanisms is of great clinical importance because it is associated with the development of serious complications from diverse organs through promotion of systemic endotoxemia. AIM: The present study was designed to investigate whether enterocytes' proliferation, apoptosis and intestinal oxidative stress are altered in the intestinal mucosa of patients with compensated and decompensated liver cirrhosis. MATERIAL AND METHODS: Twelve healthy controls (group A) and twenty four cirrhotic patients at a compensated (n = 12, group B) or decompensated condition (n = 12, group C) were subjected to duodenal biopsy. In intestinal specimens mucosal apoptotic and mitotic activity and their ratio were recorded by means of morphological assessment and mucosal lipid hydroperoxides were measured. Plasma endotoxin concentration, an index of gut barrier function, was also determined. RESULTS: Cirrhotic patients presented significantly higher serum endotoxin concentrations as compared to healthy controls (P < 0.001), whilst endotoxemia was higher in decompensated disease (P < 0.05 vs. compensated cirrhosis). Intestinal mucosal mitotic count was significantly lower in patients with compensated and decompensated cirrhosis compared to controls (P < 0.01, respectively), whilst a trend towards increased apoptosis was recorded. The mitotic/apoptotic ratio was significantly reduced in groups B (P < 0.05) and C (P < 0.01) as compared to controls. Intestinal lipid peroxidation was significantly increased in decompensated cirrhotics (P < 0.001 vs. groups A and B). CONCLUSIONS: The present study demonstrates for the first time that human liver cirrhosis is associated with decreased intestinal mucosal proliferation and proliferation/apoptosis ratio even at early stages of cirrhosis and increased intestinal oxidative stress in advanced liver disease.

Altered intestinal tight junctions' expression in patients with liver cirrhosis: a pathogenetic mechanism of intestinal hyperpermeability.

BACKGROUND: Increased intestinal permeability in cirrhosis exerts a pivotal role in the pathogenesis of spontaneous bacterial peritonitis and other complications of cirrhosis through promotion of systemic endotoxemia. This study was designed to investigate whether the expression of tight junction (TJ) proteins, which regulate gut paracellular permeability, is altered in the intestinal mucosa of patients with liver cirrhosis and study its potential association with the stage of liver disease and the development of systemic endotoxemia. DESIGN: Twenty-four patients with cirrhosis at a decompensated (n = 12, group A) or compensated condition (n = 12, group B) and 12 healthy controls (group C) were subjected to duodenal biopsy. The expression of the TJ proteins occludin and claudin-1 in the intestinal epithelium was evaluated by immunohistochemistry. Plasma endotoxin concentrations were also determined. RESULTS: Patients with cirrhosis presented significantly higher serum endotoxin concentrations as compared to healthy controls (P < 0·001), whilst endotoxemia was higher in decompensated disease (P < 0·05 vs. compensated cirrhosis). Patients with decompensated and compensated cirrhosis presented significantly reduced expression of occludin and claudin-1 as compared to controls (P < 0·01, respectively). These alterations were significantly more pronounced in decompensated patients as compared to compensated (P < 0·05). Regarding occludin, in patients with cirrhosis, a specific pattern of expression in the intestinal epithelium was observed, with a gradually increasing loss of expression from crypt to tip of the villi. Occludin and claudin-1 expression were inversely correlated with Child-Pugh score (P < 0·001), the grade of oesophageal varices (P < 0·01) and endotoxin concentrations (P < 0·001). CONCLUSIONS: This study demonstrates for the first time that human liver cirrhosis induces significant alterations in enterocytes' TJs. These changes might represent an important cellular mechanism for intestinal barrier dysfunction and hyperpermeability in patients with liver cirrhosis.

Intestinal epithelial cell proliferation, apoptosis and expression of tight junction proteins in patients with obstructive jaundice.

BACKGROUND: Intestinal hyperpermeability has been repeatedly confirmed in patients with obstructive jaundice and is considered a pivotal factor in the development of septic and renal complications in these patients. However, little is known on the mechanism(s) leading to this phenomenon. This study was undertaken to investigate the cellular and subcellular intestinal alterations in patients with obstructive jaundice. DESIGN: Sixteen patients with obstructive jaundice of malignant (n = 8, group A) or benign (n = 8, group B) aetiology, without concomitant cholangitis, and eight healthy controls (group C) were subjected to duodenal biopsy distal to the ampulla of Vater. Specimens were examined histologically and the apoptotic activity in the cryptal epithelium was recorded. Epithelial proliferation was evaluated by immunohistochemical expression of Ki67 antigen. The expression of the tight junction (TJ) proteins occludin, claudin-1, claudin-4 and claudin-7 in the intestinal epithelium was also evaluated by immunohistochemistry. RESULTS: Patients with malignant or benign obstructive jaundice presented significantly decreased intestinal epithelial cell proliferation rates compared with controls (P < 0·05), whereas no differences were detected in apoptotic activity. In a semiquantitative analysis of TJ protein expression, occludin, claudin-1 and -7 were significantly decreased (P < 0·001), whereas claudin-4 was significantly increased (P < 0·01) in jaundiced patients and their distribution was altered. No differences were detected between patients with malignant or benign obstructive jaundice for all intestinal barrier parameters studied. CONCLUSION: Decreased enterocyte proliferation and altered TJ protein expression might represent important mechanisms for intestinal barrier dysfunction and hyperpermeability in patients with extrahepatic cholestasis. The potential pharmacological modulation of these factors may lead to better control of intestinal permeability in the jaundiced patient with improved clinical outcome.

Prion protein expression and the M129V polymorphism of the PRNP gene in patients with colorectal cancer.

The prion protein, PrP(C), is known mostly for its involvement in neurodegenerative spongiform encephalopathies. However, a role for this molecule in cancer is becoming increasingly recognized partly because it promotes cell proliferation and inhibits apoptosis. Moreover, the codon 129 polymorphism (M129V) of the PRNP gene (the PrP(C)-encoding gene) has been associated with neurodegenerative disease development and severity, while no information is available regarding its role in colorectal cancer (CRC) incidence and disease progression. We have previously reported that expression levels of PRNP may have a prognostic value in CRC, suggesting a role for the prion protein in CRC. The aim of this study was to investigate retrospectively the possible role of M129V and PrP(C) expression in patients with CRC. The M129V single nucleotide polymorphism was genotyped by real time polymerase chain reactions in 110 patients with CRC and 124 healthy donors. Moreover, protein expression was assessed by immunohistochemistry in 68 patients with CRC. Allele frequencies were similar in patients and healthy controls indicating that the M129V polymorphism is not a risk factor for CRC. Furthermore, it did not correlate with any clinicopathological parameters. By contrast, PrP(C) expression was highly elevated in neoplastic compared to normal tissue and differed depending on the primary site. Interestingly, protein levels were correlated with disease recurrence (P = 0.007). Conclusively, PrP(C) overexpression may constitute a prognostic marker for disease recurrence and potentially a new target for anticancer therapy. However, further studies are needed to evaluate prospectively the role of PrP(C) expression in patients with CRC.

Histologic-type specific role of cell cycle regulators in non-small cell lung carcinoma.

BACKGROUND: Lung cancer is the most lethal type of cancer in humans. Cell cycle alterations have commonly been encountered in lung cancer and may have prognostic value. MATERIALS AND METHODS: This study investigates the immunohistochemical expression of the important cell cycle regulators phosphatase and tensin homolog deleted on chromosome 10 (PTEN), p27, Cks1, and Skp2 in 128 non-small cell lung carcinomas (64 adenocarcinomas, 46 squamous cell carcinomas, and 18 large cell undifferentiated carcinomas) and adjacent non-neoplastic lung tissue. RESULTS: PTEN and p27 were always highly expressed in non-neoplastic lung whereas Cks1 and Skp2 were not expressed in normal tissue. Decreased PTEN expression was noted in 19/64 adenocarcinomas, 15/46 squamous cell carcinomas, and 7/18 undifferentiated large cell carcinomas. Reduced expression of p27 was noted in 28/64, 19/46, and 6/18 of the tumors, respectively. Increased expression of Cks1 was seen in 38/64, 26/46, and 11/18 and increased expression of Skp2 in 29/64, 30/46, and 14/18 of the tumors, respectively. An inverse relationship between p27 and Skp2 levels was found in adenocarcinomas and between p27 and Cks1 levels in squamous cell carcinomas. Decreased PTEN and p27 expression were associated with advanced tumor stage in squamous cell carcinomas. Univariate analysis showed that high p27 and PTEN and low Cks1 expression correlated with increased survival in patients with squamous cell carcinoma independently of tumor stage. CONCLUSIONS: Aberrant expression of PTEN, p27, Cks1, and Skp2 is a common feature of all three major types of non-small cell lung cancer NSCLC, but seems to be involved in the progression of squamous cell carcinoma alone.

Histological comparison of autograft, allograft-DBM, xenograft, and synthetic grafts in a trabecular bone defect: an experimental study in rabbits.

BACKGROUND: Different types of bone-graft substitutes have been developed and are on the market worldwide to eliminate the drawbacks of autogenous grafting. This experimental animal study was undertaken to evaluate the different histological properties of various bone graft substitutes utilized in this hospital. MATERIAL/METHODS: Ninety New Zealand white rabbits were divided into six groups of 15 animals. Under general anesthesia, a 4.5 mm-wide hole was drilled into both the lateral femoral condyles of each rabbit, for a total of 180 condyles for analysis. The bone defects were filled with various grafts, these being 1) autograft, 2) DBM crunch allograft (Grafton), 3) bovine cancellous bone xenograft (Lubboc), 4) calcium phosphate hydroxyapatite substitute (Ceraform), 5) calcium sulfate substitute (Osteoset), and 6) no filling (control). The animals were sacrificed at 1, 3, and 6 months after implantation and tissue samples from the implanted areas were processed for histological evaluation. A histological grading scale was designed to determine the different histological parameters of bone healing. RESULTS: The highest histological grades were achieved with the use of cancellous bone autograft. Bovine xenograft (Lubboc) was the second best in the histological scale grading. The other substitutes (Grafton, Ceraform, Osteoset) had similar scores but were inferior to both allograft and xenograft. CONCLUSIONS: Bovine xenograft showed better biological response than the other bone graft substitutes; however, more clinical studies are necessary to determine its overall effectiveness.

Liability of the voltage-gated sodium channel gene SCN2A R19K polymorphism to oxaliplatin-induced peripheral neuropathy.

AIM: It was the aim of this study to test the hypothesis that the voltage-gated sodium channel gene SCN2A R19K polymorphism confers liability to oxaliplatin-induced peripheral neuropathy (OXLIPN). METHODS: Sixty-two patients with advanced colorectal cancer were genotyped, using allele-specific primers and SYBR green in real-time polymerase chain reaction. All patients had received adjuvant oxalipla-tin-based chemotherapy. The severity of OXLIPN was defined by means of the clinical total neuropathy score. Following the discontinuation of treatment, 36/62 patients (58.1%) developed OXLIPN. Grade I neurotoxicity was revealed in 14 (38.9%) patients and grade II neurotoxicity in 22 (61.1%) patients. RESULTS: From patients without OXLIPN (n = 26), 80.8% (n = 21) were homozygous for G, 19.2% (n = 5) were heterozygous (AG) and none was homozygous for A. The corresponding percentages for patients developing any grade of OXLIPN (n = 36) were similar. Likewise, among patients experiencing OXLIPN, insignificant differences in R19K genotypes were revealed between those with grade I versus grade II neurotoxicity. CONCLUSION: Our study failed to provide evidence to support a causal relationship between the SCN2A R19K polymorphism and OXLIPN.

The potential role of Bcl-2 expression, apoptosis and cell proliferation (Ki-67 expression) in cases of gastric carcinoma and correlation with classic prognostic factors and patient outcome.

BACKGROUND: This study investigated the presence of apoptosis and proliferation in gastric cancer and assesses their possible correlation with classic prognostic markers and patients' survival. PATIENTS AND METHODS: The study comprised 110 patients with gastric carcinoma who underwent gastrectomy for therapeutic reasons, and did not receive any pre- or postoperative treatment. Patients were followed up for 3.5-140 months. Thick paraffin sections (4 microm) were subjected to immunohistochemistry using anti-Bcl-2 and anti-Ki-67 antibodies and to in situ hybridization [TUNEL method-apoptotic body index (ABI)]. Morphological and immunohistochemical results were correlated with clinicopathologic parameters. RESULTS: Bcl-2 protein was detected in 67% of adenocarcinomas with increased expression in low-grade and early-stage tumors. Bcl-2 expression did not correlate with Ki-67 index, ABI or patients' survival. Ki-67 expression was correlated with a poorer survival rate. Apoptosis was more frequently observed in advanced stage and high-grade tumors. Cox analysis revealed that tumor stage and grade, as well as Ki-67 index, constituted independent prognostic factors. CONCLUSION: This study included patients with gastric cancer none of whom received any additional pre- or post-operative treatment. Thus the prognostic value of each marker studied was not affected by additional treatments. Bcl-2 expression in advanced-stage and high-grade gastric carcinomas, indicate that Bcl-2 is involved in early stage of tumor development. Ki-67 expression constitutes an independent prognostic factor regarding the outcome of patients with gastric cancer. The positive association between apoptosis and proliferation suggests that apoptosis might reflect not only cell loss but also the proliferative activity. However, further research is required in order to determine if these markers may provide useful information for the prediction of prognosis in patients with colorectal carcinoma.

Pathogenesis and diagnostic significance of nuclear grooves in thyroid and other sites.

Nuclear grooves are longitudinal invaginations of the nuclear envelope bilayer, which constitute a characteristic feature of papillary thyroid carcinoma. Their pathogenesis is not yet clear, but there is evidence for the involvement of a signaling pathway downstream of the protooncogene RET. The presence of nuclear grooves is not specific for papillary thyroid carcinoma because it has been documented in other types of thyroid neoplasms, in nonneoplastic thyroid lesions, in ovarian neoplasms (Brenner, adult granulosa cell, and transitional cell tumors), in breast carcinomas, in cervicovaginal and endometrial smears, in papillary neoplasms of several organs (such as papillary transitional cell carcinoma of the bladder, papillary renal cell carcinoma, papillary endometrioid carcinoma of the prostate), in thymic carcinomas, and in nonepithelial tumors.

POLR2F, ATP6V0A1 and PRNP expression in colorectal cancer: new molecules with prognostic significance?

BACKGROUND: DNA-directed RNA polymerase II subunit F (POLR2F), a subunit of the V0 domain of the vacuolar ATPase (ATP6V0A1) and the prion protein (PRNP) are molecules of potential importance in carcinogenesis and targeted cancer therapy. However, their expression has not been studied in colorectal carcinomas. PATIENTS AND METHODS: Expression microarray data were analyzed using a novel computational tool to reveal elevated levels of POLR2F, ATP6V0A1 and PRNP in relapsed colorectal carcinoma patients. The mRNA levels of POLR2F, ATP6V0A1 and PRNP were evaluated by quantitative RT-PCR in 70 colorectal carcinomas and 17 normal tissue specimens and were correlated with clinicopathological parameters. RESULTS: POLR2F and PRNP were up-regulated in colorectal carcinomas. Moreover, a significant difference in the expression levels of all three molecules between the right colon and the rectum was observed. High expression levels of POLR2F and ATP6V0A1 correlated with improved 3-year survival. Moreover, PRNP expression constituted an independent prognostic factor of the 3-year survival in multivariate analysis. CONCLUSION: POLR2F and PRNP exhibited elevated levels in carcinomas compared to normal tissue samples suggesting a possible role for these molecules in colorectal cancer. The association of the three molecules with survival or disease prognosis warrants further investigation.

Pleiotropic effects of bombesin and neurotensin on intestinal mucosa: not just trefoil peptides.

Bombesin and neurotensin are neuropeptides which exert a wide spectrum of biological actions on gastrointestinal tissues influencing intestinal growth and adaptation, intestinal motility, blood flow, secretion, nutrient absorption and immune response. Based mainly on their well-established potent enterotrophic effect, numerous experimental studies investigated their potential positive effect on the atrophic or injured intestinal mucosa. These peptides proved to be effective mucosa-healing factors, but the potential molecular and cellular mechanisms for this action remained unresolved. In a recently published study (World J Gastroenterol 2008; 14(8): 1222-1230), it was shown that their protective effect on the intestine in experimentally induced inflammatory bowel disease was related to anti-inflammatory, antioxidant and antiapoptotic actions. These results are in close agreement with our previous studies on jaundiced and hepatectomized rats that showed a regulatory effect of bombesin and neurotensin on critical cellular processes such as enterocyte' proliferation and death, oxidative stress and redox equilibrium, tight junctions' formation and function, and inflammatory response. The pleiotropic effects of bombesin and neurotensin on diverse types of intestinal injury may justify their consideration for clinical trials.

Pathophysiology of increased intestinal permeability in obstructive jaundice.

Despite advances in preoperative evaluation and postoperative care, intervention, especially surgery, for relief of obstructive jaundice still carries high morbidity and mortality rates, mainly due to sepsis and renal dysfunction. The key event in the pathophysiology of obstructive jaundice-associated complications is endotoxemia of gut origin because of intestinal barrier failure. This breakage of the gut barrier in obstructive jaundice is multi-factorial, involving disruption of the immunologic, biological and mechanical barrier. Experimental and clinical studies have shown that obstructive jaundice results in increased intestinal permeability. The mechanisms implicated in this phenomenon remain unresolved, but growing research interest during the last decade has shed light in our knowledge in the field. This review summarizes the current concepts in the pathophysiology of obstructive jaundice-induced gut barrier dysfunction, analyzing pivotal factors, such as altered intestinal tight junctions expression, oxidative stress and imbalance of enterocyte proliferation and apoptosis. Clinicians handling patients with obstructive jaundice should not neglect protecting the intestinal barrier function before, during and after intervention for the relief of this condition, which may improve their patients' outcome.

Application of paclitaxel-eluting metal stents in renal artery of pig model.

BACKGROUND AND PURPOSE: Recent reports concerning coronary, carotid, and femoral vasculature have proposed the use of drug-eluting metal stents (MS) to improve clinical and angiographic outcomes. Based on these reports, we used paclitaxel-eluting MS within an animal renal artery lumen and compared the results with those using a bare-metal stent. MATERIALS AND METHODS: The experimental model in this study was the female pig renal artery. Ten pigs with weights ranging from 25 to 30 kg were used. Twenty stents were placed, two in each animal. The MS placement was randomly performed in either the right or left renal artery of each animal. In 10 arteries, a 3.5 x 18 mm R-stent (group A) was placed; in the remaining 10 arteries, a 3 x 32 mm paclitaxel-eluting coronary stent (T-stent, group B) was inserted. Patency was estimated with the use of digital subtraction angiography, CT angiography, and virtual endoscopy at 24 hours and 1 month poststent placement. RESULTS: The positioning of the MS was successful in all cases. The initial angiographic result was maintained 24 hours after the intervention. No stent migration was seen, except for one paclitaxel stent that was acutely occluded. The one-month patency rate, as demonstrated by angiography, CT angiography, and virtual endoscopy, was 70% (8 arteries) in group A and 90% (9 arteries) in group B. The thickness of the endothelium and of the muscular coat was statistically significantly less in group B compared with group A (P = 0.0352 and P = 0.0046, respectively). CONCLUSION: These preliminary experimental study results suggest that the paclitaxel-eluting MS is more efficient than the bare-metal stent when used within the pig renal artery. Further experimental and clinical studies are necessary to validate our preliminary encouraging results.

Bcl-2, bax and p53 expression in rectal adenocarcinoma. Correlation with classic pathologic prognostic factors and patients' outcome.

BACKGROUND: Bcl-2 oncoprotein inhibits apoptosis, whereas bax protein promotes apoptosis by enhancing cell susceptibility to apoptotic stimuli. This study examined the bcl-2, bax and p53 expression in rectal adenocarcinomas and their relationship with tumor prognosis. PATIENTS AND METHODS: Paraffin-embedded 4-microm tumor sections obtained from patients with rectal adenocarcinoma who underwent colectomy for therapeutic reasons, were analyzed with a standard streptavidin biotin peroxidase method, using polyclonal and monoclonal antibodies. Patients were followed up for 1.5-83 (mean +/- SD: 47.19 +/- 6.2) months. RESULTS: Positive immunoreactivity for bcl-2, bax and p53 was detected in 21 (37%), 28 (50%) and 45 (80%) tumors, respectively. Bax was co-expressed in 17 out of 21 bcl-2(+) cases, whereas p53 was co-expressed in 18 out of 21 bcl-2(+) and 17 out of 28 bax(+) cases. Loss of bax expression was associated with advanced stage and high grade tumors (p < 0.01). Local (n = 6) or distant (n = 5) tumor recurrence was established in 11 cases. All these cases were bax(+), bcl-2(-) and p53(+). Bax and p53 expressions were correlated with adverse outcome (p < 0.05) while bcl-2 presence did not influence survival. Bcl-2(-)/bax(+)/p53(+) cases showed lower survival than bax(+)/bcl-2(+)/p53(+) cases (p < 0.001). CONCLUSION: In rectal adenocarcinoma, bax and bcl-2 proteins co-express frequently with p53. Co-expression of bax with p53 protein is associated with poor clinical outcome, especially in cases without concomitant expression of bcl-2.

Expression patterns of dysadherin and E-cadherin in lymph node metastases of colorectal carcinoma.

Reduction/loss of E-cadherin is associated with the development and progression of many epithelial tumors, while in a limited number of neoplasms, E-cadherin is re-expressed in metastases. Dysadherin, recently characterized by members of our research team, has an anti-cell-cell adhesion function and downregulates E-cadherin in a posttranscriptional manner. Colorectal cancer (CRC) is one of the most common tumors in the developed world, and lymph node metastases are harbingers of aggressive behavior. The aim of the present study was to examine the dysadherin and E-cadherin expression patterns in lymph node metastases vs primary CRC. Dysadherin and E-cadherin expression was examined immunohistochemically in 78 patients with CRC, Dukes' stage C in the primary tumor and in one lymph node metastasis. Dysadherin was expressed in 42% while E-cadherin immunoreactivity was reduced in 45% of primary tumors. In lymph nodes, 33 and 81% of metastatic tumors were positive for dysadherin and E-cadherin, respectively. Dysadherin expression was not correlated with E-cadherin expression in the primary tumor with a reverse correlation evident in the lymph node metastases. Our results suggest that different mechanisms govern E-cadherin expression in the primary tumor and the corresponding lymph node metastases.

Experimental obstructive jaundice alters claudin-4 expression in intestinal mucosa: effect of bombesin and neurotensin.

AIM: To investigate the influence of experimental obstructive jaundice and exogenous bombesin (BBS) and neurotensin (NT) administration on the expression of the tight junction (TJ)-protein claudin-4 in intestinal epithelium of rats. METHODS: Forty male Wistar rats were randomly divided into five groups: I = controls, II = sham operated, III = bile duct ligation (BDL), IV = BDL+BBS (30 microg/kg per d), V = BDL+NT (300 microg/kg per d). At the end of the experiment on d 10, endotoxin was measured in portal and aortic blood. Tissue sections of the terminal ileum were examined histologically and immunohistochemically for evaluation of claudin-4 expression in intestinal epithelium. RESULTS: Obstructive jaundice led to intestinal barrier failure demonstrated by significant portal and aortic endotoxemia. Claudin-4 expression was significantly increased in the upper third of the villi in jaundiced rats and an upregulation of its lateral distribution was noted. Administration of BBS or NT restored claudin-4 expression to the control state and significantly reduced portal and aortic endotoxemia. CONCLUSION: Experimental obstructive jaundice increases claudin-4 expression in intestinal epithelium, which may be a key factor contributing to the disruption of the mucosal barrier. Gut regulatory peptides BBS and NT can prevent this alteration and reduce portal and systemic endotoxemia.

HER Family Protein Expression in a Greek Population with Gastric Cancer. A Retrospective Hellenic Cooperative Oncology Group Study.

BACKGROUND: Gastric cancer is a relatively common malignancy. Recently, the presence of the human epidermal growth factor receptor 2 (HER2) was identified as a molecular target in a proportion of patients who benefited from the addition of appropriate anti-HER2 treatments. Our study explored the clinical and prognostic role of known HER family members, human epidermal growth factor receptor 1 (EGFR or HER1), HER2, HER3 and HER4. PATIENTS AND METHODS: Formalin-fixed paraffin-embedded (FFPE) tumor tissue samples from 249 gastric cancer patients were studied by immunohistochemistry for protein expression of EGFR, HER2, HER3 and HER4. RESULTS: Of the 249 evaluable patients, 32 did not have complete data of treatment details and/or follow-up and were excluded from the survival analyses. Of the 217 patients with complete treatment and follow-up data, 178 were operated and treated for early disease (group 1), while 39 for advanced disease (group 2). The frequency of positive EGFR, HER2, HER3 and HER4 protein expression in all patients was 17.5%, 11.8%, 14.8% and 32.9%, respectively. There were no differences in protein expression of any of the markers between the two groups. There were, however, statistically significant associations between HER4 and all other HER family members, as well as between HER2 and HER3 expression. Of note, EGFR-positive membranous protein expression was significantly associated with the presence of lymphovascular invasion (p=0.027) and HER3 and HER4 negative cytoplasmic protein expression with well/moderately-differentiated tumors (p=0.030 and p=0.014, respectively). None of the HER family members were of prognostic value for OS in univariate analysis. CONCLUSION: The present study confirmed the known protein expression frequencies of HER family members in gastric cancer in a Greek population. Several associations were observed among the HER family members and between clinicopathological characteristics and HER family members. Further research is needed on their exact prognostic role, as well as their therapeutic targeting.

Effect of bombesin and neurotensin on gut barrier function in partially hepatectomized rats.

AIM: To investigate the effect of regulatory peptides bombesin (BBS) and neurotensin (NT) on intestinal barrier function in partially hepatectomized rats. METHODS: Ninety male Wistar rats were randomly divided into five groups: I (n=0): controls, II (n= 20): sham operated, III (n=20): partial hepatectomy 70% (PHx), IV (n=20): PHx+BBS (30 microg/kg/d), V (n=20): PHx+NT (300 microg/kg/d). Groups IV and V were treated for 8 days before PHx and 48 h post surgery. At the end of the experiment, on day 10, intestinal barrier function was assessed by measuring endotoxin concentrations in portal and aortic blood. Tissue sections of the terminal ileum were examined histologically and villus density, mucosal thickness, mitotic activity and apoptosis in crypts were assessed. In addition, ileal mucosa was analyzed for DNA and protein content and microbiological analysis was performed in cecal contents. To estimate intestinal oxidative stress, lipid peroxidation was determined on tissue homogenates from terminal ileum. RESULTS: BBS or NT administration significantly reduced portal and systemic endotoxemia observed 48 h after partial hepatectomy. In hepatectomized rats (group III), a trend towards induction of mucosal atrophy was observed, demonstrated by the reduction of villus density, mucosal thickness, protein content and significant reduction of DNA, while these alterations were reversed by regulatory peptides administration. This trophic effect of BBS and NT was accompanied by induction of mitoses above control levels and a significant reduction of apoptosis in intestinal crypts. Intestinal lipid peroxidation was found significantly lower in PHx group and regulatory peptides exerted an antioxidant action, further decreasing this parameter of oxidative stress. The bacterial population of E. coli and aerobic Gram (+) cocci was increased in cecal content of hepatectomized rats, while this parameter was not affected by the administration of BBS or NT. CONCLUSION: Gut regulatory peptides BBS and NT improve intestinal barrier function and reduce endotoxemia in experimental partial hepatectomy. This effect is, at least in part, mediated by their trophic, anti-apoptotic, mitogenic, and antioxidant effect on the intestinal epithelium. This observation might be of potential value in patients undergoing liver resection.