Norman M. Pettigrew

American Joint Committee on Cancer Prognostic Factors Consensus Conference: Colorectal Working Group.

The American Joint Committee on Cancer (AJCC), which regularly reviews TNM staging systems, established a working party to develop recommendations for colorectal carcinoma.

Secretory meningioma. A distinct subtype of meningioma.

Six meningiomas with abundant hyaline inclusions (pseudopsammoma bodies) were studied. As seen by light and electron microscopy, hyaline inclusions are composed of material of varying structures located in intracellular lumina lined by microvilli. A remarkable pericytic proliferation within the vessel walls was found in five cases. In all six cases, immunohistochemical examination for multiple antigens showed positive staining for carcinoembryonic antigen and epithelial membrane antigen in inclusions and surrounding cells. Weak positivity was found for keratin and secretory component in five cases and for α-1-antitrypsin and IgM in four cases. It is concluded that secretory meningioma is a distinct type of meningioma, usually meningothelial in type. It shows characteristic light-microscopic, ultrastructural, and immunohistochemical features of epithelial and secretory differentiation with accumulation of secretory material in the form of hyaline inclusions; marked vascular pericytic proliferation is also frequently present.

Use of proliferating cell nuclear antigen as a marker of liver regeneration after partial hepatectomy in rats

In order to document and compare proliferating cell nuclear antigen (PCNA) mRNA and protein levels with more traditional parameters of hepatic regenerative activity in a rat model, adult male Sprague-Dawley rats (4 to 6 per group) were killed at various times up to 96 hours after 70% partial hepatectomy. At each time interval, tissue PCNA mRNA abundance and protein levels were documented (by Northern and Western blot analysis, respectively) and compared with the results of PCNA immunostaining and 3H-thymidine incorporation into hepatic DNA. Tissue PCNA protein levels were also documented in additional groups of rats 12, 24, 36, and 48 hours after sham or 30% partial hepatectomy. PCNA mRNA expression after partial hepatectomy was variable: almost undetectable at 24 hours, levels returned to baseline at 36 hours, then fell again to low levels at 96 hours. PCNA protein levels remained stable for 36 hours, increased to fourfold above baseline (p < 0.01) at 48 hours, then remained elevated for the duration of the 96-hour study. Changes in PCNA by immunostaining were similar but tended to occur somewhat earlier (significant increases being detectable at 24 hours), whereas 3H-thymidine incorporation detected the earliest increases in DNA synthesis at 12 hours and peaked at 36 hours. Peak PCNA protein levels correlated with the extent (0%, 30%, or 70%) of hepatic resection. The results indicate that PCNA protein level as determined by Western blot analysis, but not PCNA mRNA expression, correlates with PCNA immunostaining and 3H-thymidine incorporation in the regenerating liver. These findings support the use of PCNA protein determinations as an additional quantitative measure of hepatic regenerative activity after partial hepatectomy in rats.

Expression of mRNA for epidermal growth factor, transforming growth factor-alpha and their receptor in human prostate tissue and cell lines.

Enhanced expression of the epidermal growth factor receptor (EGFR) or its ligands, epidermal growth factor (EGF) and transforming growth factor alpha (TGF-α) can increase signalling via receptor-mediated pathways which may lead to excessive proliferation and cellular transformation. Such autocrine regulation of growth has been demonstrated for prostate cancer cell lines in culture but its role in prostate cancerin vivo has not been established. To assess the potential of such a mechanism, we have examined the pathway components in prostate carcinomas (CaP) in comparison with non-malignant benign prostatic hyperplasias (BPH). In the present study, we investigate the dosage, structure and expression of EGF, TGF-α and EGFR genes in a series of 34 human prostate samples and 3 prostate cancer cell lines. All of the samples contained transcripts from each of the genes. The expression of pre-pro-TGF-α mRNA and pre-pro-EGF mRNA were significantly higher in CaP (n=13) than BPH (n=21) specimens (p<0.05). The androgen-responsive prostatic carcinoma cell line, LNCaP, expressed high levels of EGF mRNA while the androgen-independent DU145 and PC-3 cell lines expressed high levels of TGF-α mRNA and EGFR mRNA. In general, overexpression of these mRNAs was not associated with amplification or detectable gene rearrangment; only DU145 cells demonstrated any alteration in these genes, with apparent amplification of the TGF-α gene. Relative to BPH, all prostate carcinomas and cell lines studied had elevated levels of mRNA for one or both mRNA coding for the ligands for EGFR. Thus enhanced expression of the ligands and co-expression of the EGF receptor are frequent events in human prostate tumors, consistent with the cell culture data supporting autocrine growth regulation via EGFR-mediated pathways.

IMMUNOHISTOCHEMICAL ASSAY FOR OESTROGEN RECEPTORS IN PARAFFIN WAX SECTIONS OF BREAST CARCINOMA USING A NEW MONOCLONAL ANTIBODY

The aim of this study was to evaluate the utility of a new monoclonal antibody (AER311) that targets the oestrogen receptor (ER) in an immunohistochemical assay (IHA) applied to breast cancers. Ninety‐seven cases of invasive ductal carcinoma were studied by AER311‐IHA using a pressure‐cooking antigen retrieval technique applied to formaldehyde‐fixed, paraffin‐embedded tissue sections; immunostaining was assessed by semi‐quantitative scoring (H score). There was 80 per cent concordance between the ER status measured by dextran‐coated charcoal (DCC) assay and AER311‐IHA, with 63/97 (65 per cent) tumours positive and 15/97 (15 per cent) tumours negative by both assays. Of the 12 DCC‐positive cases that were negative by AER311‐IHA, 11 were borderline positive (3–8 fmol/mg). Similarly, six of seven DCC‐negative cases that scored positive by AER311‐IHA had only borderline positive H scores (<50). When AER311‐IHA was compared with 1D5‐IHA, there was good concordance in ER status (77 per cent) and a significant correlation (r=0·7, P<0·001) between H scores. Nevertheless, the correlation between ER level determined by AER311‐IHA and that measured by DCC (r=0·53, P<0·001) was higher than that for 1D5‐IHA (r=0·32, P=0·002). AER311‐IHA can therefore provide reliable information about the ER status of breast carcinoma on paraffin sections and is an acceptable alternative to other commercially available monoclonal antibodies.

Serum immunoglobulins predict the extent of hepatic fibrosis in patients with chronic hepatitis C virus infection

Summary.  Recently, we documented that immunoglobulins stimulate the proliferative activity of rat hepatic stellate cells in vitro. The aim of the present study was to determine whether there is any association between serum immunoglobulin levels and hepatic fibrosis in patients with chronic hepatitis C virus (HCV) infection. Charts from 116 patients with biochemical, serologic, virologic and histologic evidence of chronic hepatitis C infection and serum immunoglobulin levels (IgA, IgG, IgM and total) were reviewed. The mean (±SD) age of the study population was 46 ± 11 years and 67 (58%) were male. There were significant correlations between serum IgA (r = 0.39, P = 0.00001), IgG (r = 0.49, P = 0.000002) and total (r = 0.51, P = 0.000003) immunoglobulin levels and the stage of hepatic fibrosis. When serum immunoglobulin levels were included into logistic regression analysis with variables known to be associated with advanced disease (male gender, age >40 years at onset of infection, duration of infection beyond 20 years and concurrent alcohol abuse) only IgA, IgG and total immunoglobulin levels (P < 0.05, <0.05 and <0.005, respectively) emerged as independent predictors of hepatic fibrosis. Our data indicate a strong association between serum immunoglobulin levels (IgA, IgG and total) and hepatic fibrosis in patients with HCV infection. This finding supports the need to further investigate whether immunoglobulins independently promote disease progression in patients with chronic HCV infection.

The diagnostic yield of lower endoscopy plus biopsy in nonbloody diarrhea

BACKGROUND Patients presenting with diarrhea frequently undergo lower endoscopy plus biopsy as part of their diagnostic evaluation. The diagnostic yield of this approach has not been systematically evaluated. METHODS To evaluate the diagnostic yield of endoscopy and biopsy in the investigation of nonbloody diarrhea, we performed a retrospective analysis using the endoscopy unit database of a tertiary care university hospital over a 3-year period. The database was searched for cases in which colonoscopy was performed for the single indication of diarrhea. The endoscopic findings and initial biopsy reports were extracted from a chart review, and each clinician was interviewed for the patients current clinical diagnosis. The clinical diagnoses were compared with the endoscopy and biopsy results to determine whether the tests had contributed to making the clinical diagnoses. RESULTS Three hundred six patients were identified. One hundred one were excluded for standardized predefined exclusion criteria, leaving 205 evaluable patients, of whom 77 had flexible sigmoidoscopy and 128 had colonoscopy. Eighteen percent had specific clinical diagnoses facilitated by endoscopy and/or biopsy. Endoscopy and biopsy results were normal in 74% of cases. In 8% of the cases either the endoscopy or biopsy findings were inconsistent with the final clinical diagnoses. CONCLUSIONS Endoscopy and biopsy are important diagnostic tools in the evaluation of patients with nonbloody diarrhea, leading to a specific diagnosis in nearly one fifth of cases.

Decreased hepatocyte membrane potential differences and GABAa‐β3 expression in human hepatocellular carcinoma

To determine whether hepatocyte membrane potential differences (PDs) are depolarized in human HCC and whether depolarization is associated with changes in GABAA receptor expression, hepatocyte PDs and γ‐aminobutyric acid (GABA)A receptor messenger RNA (mRNA) and protein expression were documented in HCC tissues via microelectrode impalement, real‐time reverse‐transcriptase polymerase chain reaction, and Western blot analysis, respectively. HCC tissues were significantly depolarized (−19.8 ± 1.3 versus −25.9 ± 3.2 mV, respectively [P < 0.05]), and GABAA‐β3 expression was down‐regulated (GABAA‐β3 mRNA and protein expression in HCC; 5,693 ± 1,385 and 0.29 ± 0.11 versus 11,046 ± 4,979 copies/100 mg RNA and 0.62 ± 0.16 optical density in adjacent tumor tissues, respectively [P = 0.002 and P < 0.0001, respectively]) when compared with adjacent nontumor tissues. To determine the physiological relevance of the down‐regulation, human malignant hepatocytes deficient in GABAA‐β3 receptor expression (Huh‐7 cells) were transfected with GABAA‐β3 complementary DNA (cDNA) or vector alone and injected into nu/nu nude mice (n = 16‐17 group). Tumors developed after a mean (± SD) of 51 ± 6 days (range: 41‐60 days) in 7/16 (44%) mice injected with vector‐transfected cells and 70 ± 12 days (range: 59‐86 days) in 4/17 (24%) mice injected with GABAA‐β3 cDNA‐transfected cells (P < 0.005). Conclusion: The results of this study indicate that (1) human HCC tissues are depolarized compared with adjacent nontumor tissues, (2) hepatic GABAA‐β3 receptor expression is down‐regulated in human HCC, and (3) restoration of GABAA‐β3 receptor expression results in attenuated in vivo tumor growth in nude mice. (HEPATOLOGY 2007;45:735–745.)

Are chronic hepatitis C viral infections more benign in patients with hemophilia

BACKGROUND AND AIMS:Cirrhosis is associated with thromboses of the intrahepatic vasculature. This raises the possibility that HCV infections in hemophiliacs may differ from those in nonhemophiliacsMETHODS:Liver biopsy findings from 12 hemophiliacs and 20 age- and gender-matched, nonhemophiliac controls with chronic hepatitis C viral (HCV) infections were compared for inflammatory activity and fibrosis.RESULTS:The mean ages of hemophiliacs and controls were 35.0 ± 3.0 yr and 39.6 ± 5.6 yr, respectively (P = 0.2). Serum aspartate aminotransferase (AST) levels were lower (44 ± 13 vs 70 ± 43 U/L) and the duration of the partial thromboplastin (PTT) time longer (49.2 ± 16.9 vs 31.2 ± 1.2 s.) in hemophiliacs than in controls (P < 0.02 and <0.001, respectively). Six of the seven hemophiliac patients (86%) and 8/17 controls (46%) were infected with genotypes 1a or 1b with the remainder being infected with 2b, 3a, or 3b. Histological activity and fibrosis scores were significantly lower in hemophiliacs than in controls (1.9 ± 0.6 vs 3.6 ± 2.7 and 0.3 ± 0.2 vs 1.5 ± 1.5, P < 0.05 and P < 0.01, respectively). None of the hemophiliacs had histological evidence of advanced disease (bridging fibrosis and/or cirrhosis) as compared to 7/20 (30%) controls (P < 0.05).CONCLUSION:HCV infections in hemophiliacs may be less severe than in HCV infected patients without hemophilia.

Crohn's Disease Recurrence in a Small Bowel Transplant

This is a report of a patient with short-bowel syndrome secondary to recurrent surgeries for Crohns disease who ultimately required small bowel transplantation in 1994. Eight years posttransplantation he developed recurrent Crohns disease that was responsive to prednisone. From the perspective of advancing our understanding of Crohns disease pathogenesis this case suggests that intestine-specific antigens may be more important than the classical MHC antigens for the development of Crohns disease, since this man developed Crohns disease in both the native intestine and also in the engrafted one.