Biomarkers of benefit from cetuximab-based therapy in metastatic colorectal cancer: interaction of EGFR ligand expression with RAS/RAF, PIK3CA genotypes.

BACKGROUND: More than half of patients with KRAS-wild type advanced colorectal cancer (CRC) fail anti-EGFR monoclonal antibodies. We studied EGFR-axis messenger RNA (mRNA) expression and RAS, RAF, PIK3CA mutations in order to identify additional biomarkers of cetuximab efficacy. METHODS: Previously genotyped (KRAS, NRAS, BRAF, PIK3CA mutations) formalin-fixed paraffin-embedded tumour biopsies of 226 cetuximab-treated CRC patients (1st to 3rd line therapy) were assessed for mRNA expression of epidermal growth factor receptor (EGFR) and its ligands EGF, Transofrming Growth Factor-a (TGFA), Amphiregulin (AREG) and Epiregulin (EREG) with real time quantitative PCR. Mutations were detected in 72 (31.9%) tumours for KRAS, in 6 (2.65%) for BRAF, in 7 (3.1%) for NRAS and in 37 (16.4%) for PIK3CA. RESULTS: Only PIK3CA mutations occasionally coexisted with other gene mutations. In univariate analysis, prognostic significance for survival ( from metastases until death) was seen for BRAF mutations (Hazard Ratio HR 8.1, 95% CI 3.4-19), codon 12-only KRAS mutations (HR 1.62, 95% CI 1.1-2.4), high AREG mRNA expression only in KRAS wild type CRC (HR 0.47, 95% CI 0.3-0.7) and high EREG mRNA expression irrespective of KRAS mutation status (HR 0.45, 95% CI 0.28-0.7). EREG tumoural mRNA expression was significantly associated with a 2.26-fold increased likelihood of objective response to cetuximab therapy (RECIST 1.1). In multivariate analysis, favourable predictive factors were high AREG mRNA in KRAS wild type tumours, high EREG mRNA, low Ephrin A2 receptor mRNA. Cetuximab-treated patients with AREG-low KRAS wild type CRC fared very poorly, their survival being similar to KRAS mutant CRC. Patients with KRAS codon 13 or other non-codon 12 mutations had a median survival (30 months, 95% CI 20-35) similar to that of patients with KRAS wild-type (median survival 29 months, 95% CI 25-35), in contrast to patients with KRAS codon 12 mutations who fared worse (median survival 19 months, 95% CI 15-26). CONCLUSIONS: BRAF and codon 12 KRAS mutations predict for adverse outcome of CRC patients receiving cetuximab. AREG mRNA reflects EGFR signalling in KRAS wild type tumours, predicting for cetuximab efficacy when high and failure when low. EREG may have a prognostic role independent of KRAS mutation.

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.

Effect of long-term treatment with rituximab on pulmonary function and skin fibrosis in patients with diffuse systemic sclerosis.

OBJECTIVES: To assess the safety and efficacy of long-term treatment with rituximab (RTX) in patients with systemic sclerosis (SSc). METHODS: Eight patients with SSc-associated interstitial lung disease (ILD) received 4 cycles of RTX and had a follow-up of 2 years. Lung involvement was assessed by pulmonary function tests and chest HRCT. Skin involvement was assessed both clinically and histologically. RESULTS: We found a linear improvement of lung function and skin thickening over the 2 years of RTX treatment. There was a significant increase of FVC at 2 years compared to baseline (mean ± SEM: 77.13±7.13 vs. 68.13±6.96, respectively, p<0.0001). Similarly, DLco increased significantly at 2 years compared to baseline (mean ± SEM: 63.13±7.65 vs. 52.25±7.32, respectively, p<0.001). Skin thickening, assessed with the MRSS, improved significantly at 2 years compared to baseline (mean ± SEM: 4.87±0.83 vs. 13.5±2.42, respectively, p<0.0001). A reduction in myofibroblast score was seen histologically following RTX treatment. CONCLUSIONS: Our results indicate that long-term treatment with RTX may favourably affect lung function and skin fibrosis in patients with SSc. Larger scale, multicentre, randomised, controlled studies are needed to further explore the efficacy of RTX in SSc.

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.

Experience with rituximab in scleroderma: results from a 1-year, proof-of-principle study.

OBJECTIVE: To assess the efficacy of rituximab (RTX) in SSc. METHODS: Fourteen patients with SSc were evaluated. Eight patients were randomized to receive two cycles of RTX at baseline and 24 weeks [each cycle consisted of four weekly RTX infusions (375 mg/m(2))] in addition to standard treatment, whereas six patients (control group) received standard treatment alone. Lung involvement was assessed by pulmonary function tests (PFTs) and chest high-resolution CT (HRCT). Skin involvement was assessed both clinically and histologically. RESULTS: There was a significant increase of forced vital capacity (FVC) in the RTX group compared with baseline (mean +/- s.d.: 68.13 +/- 19.69 vs 75.63 +/- 19.73, at baseline vs 1-year, respectively, P = 0.0018). The median percentage of improvement of FVC in the RTX group was 10.25%, whereas that of deterioration in the controls was 5.04% (P = 0.002). Similarly, diffusing capacity of carbon monoxide (DL(CO)) increased significantly in the RTX group compared with baseline (mean +/- s.d.: 52.25 +/- 20.71 vs 62 +/- 23.21, at baseline vs 1-year respectively, P = 0.017). The median percentage of improvement of DL(CO) in the RTX group was 19.46%, whereas that of deterioration in the control group was 7.5% (P = 0.023). Skin thickening, assessed with the Modified Rodnan Skin Score (MRSS), improved significantly in the RTX group compared with the baseline score (mean +/- s.d.: 13.5 +/- 6.84 vs 8.37 +/- 6.45 at baseline vs 1-year, respectively, P < 0.001). CONCLUSION: Our results indicate that RTX may improve lung function in patients with SSc. To confirm our encouraging results we propose that larger scale, multicentre studies with longer evaluation periods are needed.

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.

The prognostic value of frozen section preimplantation graft biopsy in the outcome of renal transplantation.

INTRODUCTION: Preimplantation biopsy provides a window on the state of the renal allograft. In this study, the prognostic value of frozen section preimplantation graft biopsy was estimated and compared to regularly processed formalin-fixed biopsy. MATERIALS AND METHODS: Seventy-four renal allograft recipients were studied. The degree of glomerulosclerosis, acute tubular necrosis, interstitial fibrosis, arteriosclerosis, and arteriolosclerosis was rapidly estimated in frozen sections and correlated to the renal function in the immediate posttransplantation period and 3 months thereafter. The histological changes were also examined in paraffin-embedded sections. RESULTS: The histological changes observed in rapidly processed frozen sections were comparable to those observed on regularly processed sections and their differences did not reach statistical significance. Glomerulosclerosis and arteriolosclerosis were underestimated, whereas acute tubular necrosis and interstitial fibrosis were overestimated, in the frozen sections compared to permanent ones, but those differences were not statistically significant. Immediate graft function was observed in 45 patients (61%). Delayed graft function was more frequently observed among recipients with donor age above 60 years (57% vs. 32%). Serum creatinine 3 months after transplantation was above 2 mg/dL in 33 recipients (44.5%) and was positively correlated to the degree of tubular necrosis (p = 0.04) and donor age (p = 0.03). Donor age was correlated to the degree of arteriolosclerosis (p < 0.01). CONCLUSIONS: Frozen section preimplantation biopsy gives reliable information for the situation of the graft that is related to the outcome of renal transplantation.

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.

Tuberculosis of the parotid gland.

Tuberculosis (Tbc) presented as an isolated parotid mass is rare. Preoperative diagnosis is difficult and the symptomatology is nonspecific. In the majority of the cases an initial diagnosis of a parotid tumor, often a pleomorphic adenoma, is made. We present a 35-year old woman with a six months duration right parotid lump. The mass was firm and nontender without ipsilateral cervical lymphadenopathy, suggesting a parotid neoplasm. The computerized tomography scan showed an intraparotideal tumor resembling a pleomorphic adenoma and thus the patient underwent to a superficial parotidectomy. Fine needle aspiration biopsy was performed but it was not diagnostic. Histological examination revealed an intraparotideal lymph node with changes of granulomatous lymphadenopathy type, like those demonstrated in the tuberculosis and sarcoidosis. Ziehl-Nielsen staining was negative, while the tuberculin skin test (PPD, 5 IU) was positive. The patient's treatment regimen consisted of a 2-month initial phase of isoniazid, rifampin, pyrazinamide and ethambutol followed by a 7 month continuation phase of isoniazid and rifampin. Postoperatively, there was only a mild paresis of the facial nerve resolved a week after. Parotid Tbc is very rare but should be considered as a differential diagnosis of parotid lumps. Fine needle aspiration biopsy (FNAB) is of outmost importance for diagnosis, since the treatment of this entity is primarily conservative. However, surgery could be both therapeutic and diagnostic, especially when other diagnostic examinations fail.

Oval cell proliferation in cirrhosis in rats. An experimental study.

AIM: Oval cells are liver stem cells involved in liver regeneration following liver damage. Previous studies have shown that pretreatment with a hepatocyte inhibitor is required to allow full oval cell activation. This study investigates whether oval cells develop and proliferate in a model of experimental liver fibrosis without pretreatment with a known hepatocyte inhibitor. METHODS: The study comprised 66 male Wistar rats divided into two groups: A (n = 6): controls; and B (n = 60): CCl(4) injection (intraperitoneally 2 mL/kg bodyweight 1:1 volume in corn oil twice weekly). Rats were sacrificed at four, eight and 12 weeks. Liver tissues were evaluated for the degree of fibrosis (Masson's trichrome), cell proliferation (Ki67 antigen), expression of alpha-fetoprotein (AFP) mRNA (RT-PCR and in situ hybridization), AFP protein (Western blot) and cytokeratin-19. Cells with morphologic features of oval cells that were cytokeratin 19 (CK19)+ and AFP mRNA+ were scored in morphometric analysis. RESULTS: Oval cells were present in all 66 specimens; their percentage was higher in group B compared to group A (P < 0.001). AFP mRNA and protein expression increased as fibrosis advanced. Similarly, the numbers of CK19+, AFP mRNA+ and Ki67+ oval cells were higher in advanced fibrosis stages. CONCLUSION: This study demonstrates that oval cells develop and proliferate in a model of experimental liver fibrosis without pretreatment with a known hepatocytic inhibitor. However, further research is warranted in order to identify the exact molecular mechanisms involved in this process.

Increased Bax/Bcl-2 ratio up-regulates caspase-3 and increases apoptosis in the thymus of patients with myasthenia gravis.

BACKGROUND: In this study the possible relation of Bax (an apoptosis promoter) to Bcl-2 (an apoptosis inhibitor) ratio with the apoptosis co-ordination enzyme, caspase-3, in the thymus of patients with myasthenia gravis (MG) was investigated in correlation with long-term clinical prognosis. PATIENTS AND METHODS: The study included 46 patients (17M/29F, mean age 36.60 +/- 16.09 yr) with MG, who underwent thymectomy for treatment. The clinical staging (Osserman classification) included: stage 1-5, IIA-21, IIB-17, III-3. The pathology of the thymus showed: hyperplasia-26, atrophy-8, thymoma B1 and B2 type-9, thymoma B3 type (well differentiated thymic carcinoma)-3. The patients were evaluated 39-166 (mean 91.87 +/- 38.38) months after thymectomy. At the end of the follow-up period, the patients were classified as follows: group A: complete stable remission, group B: pharmacological remission + minimal manifestations + improvement + deterioration. Paraffin sections of thymic tissue were subjected to: a) immunohistochemistry (bax, bcl-2, caspase-3 protein); b) in situ hybridization (bax, bcl-2 mRNA); and c) TUNEL-stain (apoptotic cells). Bax to bcl-2 mRNA and protein ratio was determined for each sample by dividing the % bax (+) cells by the % bcl-2 (+) cells. RESULTS: Follow-up data were available for 39/46 patients: 13/39 patients belonged to group A and 26/39 to group B. The Bax/Bcl-2 mRNA and protein ratios were increased towards advanced disease stages (+370% for mRNA and +391% for protein, from MG stage I to stage III). These ratios were correlated with caspase-3 expression (r = 0.782 and 0.583, p < 0.01) and apoptosis (r = 0.591 and 0.358 p < 0.01 and p < 0.05). All the 13 cases in group A had a Bax/Bcl-2 ratio < 1 (mean +/- SD: 0.58 +/- 0.04 for mRNA and 0.62 +/- 0.03 for protein), whereas all the 26 cases of group B had a ratio > 1 (1.47 +/- 0.07 for mRNA and 1.52 +/- 0.18 for protein). The Kaplan-Meier survival curve showed higher, free of disease, survival in group A (p = 0.0082). Cox regression analysis revealed that the Bax/Bcl-2 ratio was an independent prognostic factor, however the p-value was marginally significant (95% CI: 1.078-44.073, p = 0.041). CONCLUSION: This study has demonstrated that in patients with MG who underwent thymectomy: a) the Bax/Bcl-2 ratio may up-regulate caspase-3 expression and modulate apoptosis associated with progress of the disease; b) the Bax/Bcl-2 ratio < 1 was associated with complete stable remission after thymectomy; and c) Bax/Bcl-2 ratio was an independent predictive marker for therapeutic response after thymectomy.

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.

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.

Hepatocellular carcinoma in hepatectomized patients: biologic and therapeutic implications.

UNLABELLED: The macroscopic and microscopic features of 60 hepatocellular carcinomas (HCC) were investigated and correlated with patients' disease-free survival. PATIENTS AND METHODS: The study included 60 HCCs removed, by partial hepatectomy, from an equal number of patients. In these tumors, several macroscopic and microscopic features were assessed, graded and correlated with disease-free survival. RESULTS: HCCs begin as small, well-differentiated tumors that have an increased proliferation rate and neovascularization. Vascular invasion, which is the strongest predictor of disease recurrence, correlated significantly with tumor number and size, the predominant and worst degree of differentiation, and the apoptosis/mitosis ratio. In the absence of macroscopic or large vessel invasion, the largest tumor size (p = 0.006), apoptosis/mitosis ratio (p = 0.03) and number of tumors (p = 0.04) were independent predictors of disease-free survival. CONCLUSION: This study showed that, in humans, the prognosis of HCC depends on several biological factors. Aggressive biological behavior (vascular invasion and recurrence) correlated significantly with: a) alterations in the apoptosis/mitosis ratio and b) architectural and cellular alterations.

Intestinal barrier dysfunction in cirrhosis: Current concepts in pathophysiology and clinical implications.

The intestinal lumen is a host place for a wide range of microbiota and sets a unique interplay between local immune system, inflammatory cells and intestinal epithelium, forming a physical barrier against microbial invaders and toxins. Bacterial translocation is the migration of viable or nonviable microorganisms or their pathogen-associated molecular patterns, such as lipopolysaccharide, from the gut lumen to the mesenteric lymph nodes, systemic circulation and other normally sterile extraintestinal sites. A series of studies have shown that translocation of bacteria and their products across the intestinal barrier is a commonplace in patients with liver disease. The deterioration of intestinal barrier integrity and the consulting increased intestinal permeability in cirrhotic patients play a pivotal pathophysiological role in the development of severe complications as high rate of infections, spontaneous bacterial peritonitis, hepatic encephalopathy, hepatorenal syndrome, variceal bleeding, progression of liver injury and hepatocellular carcinoma. Nevertheless, the exact cellular and molecular mechanisms implicated in the phenomenon of microbial translocation in liver cirrhosis have not been fully elucidated yet.

Expression of CD44 protein in renal cell carcinomas: association with p53 expression.

CD44 is an adhesion molecule involved in cell-to-cell and cell-to-matrix interactions. Recent evidence indicates a role of CD44 in tumor growth and metastatic potential of tumor cells. Moreover, it is widely known that the p53 tumor suppressor gene controls cell proliferation and loss of its normal function may lead to carcinogenesis. To investigate the role of these biomarkers in renal cancer, we analyzed the immunohistochemical distribution of CD44's expression on formalin fixed paraffin embedded tissue from 67 renal cell carcinomas and correlated with clinicopathologic parameters as well as with p53 suppressor gene expression. The monoclonal antibodies CD44 and p53 were applied to the tissues using the streptavidin biotin peroxidase method after microwave antigen retrieval. For CD44 and p53 more than 10% membranous and 5% nuclear staining, respectively, were estimated as positive. CD44's membranous immunoreactivity was detected in 24/67 tumors (35%) and mostly in carcinomas of clear/granular cell type. Nine tumors expressed nuclear immunoexpression of p53 protein (13.4%). Statistically significant correlation was noted between CD44 expression and nuclear grade (P < 0.001), tumor stage (P < 0.001), vascular invasion (P < 0.05) and p53 expression (P < 0.01). These results suggest that CD44s and p53 are markers of tumor progression in renal cell cancer.

The potential role of bcl-2 mRNA and protein exression in hepatocellular carcinomas.

BACKGROUND: The bcl-2 gene regulates programmed cell death by providing a survival advantage to rapidly proliferating cells. In several malignant tumors bcl-2 presence has been associated with favorable prognosis. In the liver, bcl-2 is expressed in bile ductular cells and tumors of biliary origin. This study investigates the expression of bcl-2 mRNA and protein in hepatocellular carcinomas (HCC). MATERIALS AND METHODS: The study comprised 35 primary HCC resected from 35 patients; 21 males and 14 females, aged from 43-59 years. The tumors were graded according to Edmondson criteria. In 28 cases HCC was developed on the background of cirrhotic liver. In 9 instances the patients received chemoembolization before surgery. The presence of bcl-2 mRNA was assessed on paraffin-embedded, 4 microm-thick sections, using a standard in situ hybridization method with a commercially available bcl-2 probe (Maxim Biotech, USA), while the streptavidin-biotin immunohistochemical technique was employed to detect bcl-2 protein expression using the monoclonal anti-bcl-2 antibody (DAKO, USA). The results were expressed as % of tumor-positive cells following morphometric analysis. RESULTS: The in situ hybridization study revealed bcl-2 mRNA expression in 25 out of 35 (70%) HCC. In addition, bcl-2 mRNA was detected in hyperplastic cholangioles within fibrous septae in the periphery of the tumors. Immunohistochemical staining failed to reveal any bcl-2 protein expression in tumor cells of HCC, whereas hyperplastic cholangioles of the fibrous septae, in the periphery of the tumors and intratumoral lymphocytes displayed a strong-positive cytoplasmic (perinuclear) stain. No significant correlations were recorded between bcl-2 mRNA expression and tumor histological pattern, grade, stage and the use of previous chemoembolization. CONCLUSION: In hepatocellular carcinomas, the bcl-2 gene is frequently present but its protein product is absent. This suggests a post-translational mechanism of bcl-2 protein degradation, indicating that bcl-2 does not play a substantial role in the progress of hepatocellular carcinoma.

Immunohistochemical expression of TGF-beta1, p21WAF1, p53, Ki67, and angiogenesis in gastric carcinomas: a clinicopathologic study.

BACKGROUND: Transforming growth factors-beta (TGF-betas) are multifunctional polypeptides with crucial role as regulators of cellular growth and differentiation. It has been reported that TGF-beta1 plays a biphasic action on tumorigenesis thus inducing or inhibiting malignant properties of the epithelial cells. METHODS: TGF-beta1 expression was analyzed in 56 patients with gastric carcinoma by immunohistochemical methods and compared with the expression of p21, p53, and Ki67, as well as with angiogenesis. The correlation of these markers with clinicopathological parameters was also evaluated. RESULTS: TGF-beta1 expression was detected in 71% of tumors and was more frequent in adenocarcinomas of the intestinal type (p < 0.001). Positivity of p21WAF1, and p53 was observed in 32% and 51% of the tumors, respectively. A high Ki67 proliferating index was detected in 53.5% of the tumors. TGF-beta1 expression was significantly correlated with p21 expression (p < 0.001) and was inversely correlated with microvessel density. p21 expression was also higher in tumors with low proliferating index (p < 0.01). There was no apparent correlation between the expression of these markers and tumor stage, depth of invasion, or lymphnode metastases. CONCLUSION: The findings show that TGF-beta1 may be involved in the activation of the cdk inhibitor p21WAF1 in gastric adenocarcinomas, suggesting p53-independent induction of p21 in gastric cells. TGF-beta1 does not seem to contribute to the alteration of the angiogenic status of these tumors.

The effect of ischemia on the regeneration of the cholestatic liver. An experimental study.

BACKGROUND/AIMS: Cholestatic liver is known to be more susceptible to ischemia than normal liver. In this study we assessed the histopathologic features of hepatic ischemic damage and liver regeneration in rats with experimental obstructive jaundice. METHODOLOGY: The study comprised 90 male Wistar rats. These were assigned randomly to 4 groups according to the surgical procedure they underwent: I (n = 10) controls (non-operated), II (n = 10) sham-operated, III (n = 30) occlusion of hepatic artery and portal vein (total liver ischemia), and IV (n = 40) ligation and division of the common bile duct ligation. Rats of group III were sacrificed 15 (IIIa), 30 (IIIb) and 60 min (IIIc) after total liver ischemia was done. Ten days after bile duct ligation, 10 rats of group IV underwent euthanasia, whereas the remaining 30, underwent total liver ischemia and were sacrificed after 15 min (IVb), 30 min (IVc), and 60 min (IVd). Liver wedge biopsies (left anterior lobe) were obtained and histologic examination included hematoxylin and eosin, and immunohistochemical stains for cytokeratin AE1, HEPPAR (hepatocyte paraffin antigen), and antigen Ki67. Immunohistochemical results for Ki67 were expressed following morphometric analysis. RESULTS: Liver sections from category IVa showed large duct obstruction features, and those from group III, ischemic chages including centrilobular hepatocellular swelling and necrosis, hepatocanalicular cholestasis, and mild portal mononuclear/mixed inflammation. Sections from groups IVB, IVc, IVd displayed together changes of large duct obstruction and ischemia, and in categories IVc (bile duct ligation +30 min total liver ischemia), and IVd (bile duct ligation +60 min total liver ischemia) necrosis of the large bile ducts was present. The total liver parenchymal area affected (% necrosis) was higher in categories IVd, and IVc compared to categories IVb (P < 0.05), and IIIc, IIIb, IIIa (P < 0.01). All 60 total liver ischemia-liver biopsies, developed features of liver regeneration that originated from zone 2, extended to zone 1 and occasionally to zone 3. Immunohistochemical stains revealed cells positive to AE1 and cells positive to HEPPAR. Proliferation rate (% Ki67+ cells) was higher in category IIIa compared to categories IIIb, IIIc, IVb, IVc, and IVd (P < 0.05). CONCLUSIONS: Our study shows that liver ischemia induces more severe hepatocyte damage in livers with obstructive cholangiopathy compared to normal ones. Liver regenerative process is mediated mainly by proliferation of non-necrotic cells that express hepatocellular or ductular epithelial features. Proliferation rate of hepatocytes is lower when liver ischemia and obstructive jaundice coexist.