Redefining the significance of aneuploidy in the prognostic assessment of colorectal cancer

The aberrant content of DNA, or aneuploidy, is a hallmark of tumor cells and may be associated with malignant potential. Based on the hypothesis that aneuploidy, as a form of genetic instability, results in an increased capability to generate cell heterogeneity, we investigated whether a comprehensive assessment of aneuploidy extent and degree might be a reliable indicator of tumor aggressiveness. DNA content was determined by flow cytometry in the infiltrating front of 131 paraffin-embedded primary colorectal carcinomas collected in a prospective design. Enrichment of tumor cells by sample microdissection resulted in neoplastic cell contents above 75%. An estimate of aneuploidy, the aneuploidy index (AI), was calculated as the tumor DNA content adjusted by the percentage of diploid and aneuploid cells in G0/G1. Thirty-nine tumors were diploid, 90 hyperdiploid, and 2 hypodiploid. The mean AI in aneuploid tumors was 1.20+/-0.17 and correlated with Dukes' stage and metastasis (p < 0.05). A high AI (receiver operating characteristic curve cutoff value greater than 1.14) predicted a poorer outcome in univariate (p = 0.004) and multivariate (p = 0.01) analyses. Based on these results, we postulate that aneuploidy is the molecular engine of progression in a subset of colorectal cancers, in which the AI seems to be a sensible and independent gauge of malignant potential. The AI determination may have prognostic application in colorectal cancer, especially in low-grade tumors, which might benefit from coadjuvant therapies.     

Immunity in HIV-1-Infected Adults with a Previous State of Moderate-Severe Immune-Suppression and More Than 500 CD4+ T Cell After Highly Active Antiretroviral Therapy

We evaluated phenotypic and functional parameters of immune restoration of 27 HIV-infected patients on highly active antiretroviral therapy (HAART) (HIV-cases) with HIV-RNA levels below detectable limits at least during 18 months, and CD4+ cell per microliter higher than 500 at the moment of the study and lower than 300 anytime before. These patients were compared with 11 HIV-controls that never had less than 500 CD4+ cell per microliter and 20 healthy-controls (HIV seronegative subjects) in a cross-sectional study. HIV-cases had lower counts of naïve CD4+ than HIV-controls and healthy-controls. HIV-patients (both HIV-cases and HIV-controls) showed higher values of naïve and memory CD8+ counts than healthy-controls. TREC-bearing cell levels were significantly lower in HIV-cases than in healthy-controls. Peripheral blood mononuclear cells (PBMC) cultures, HIV-cases had lower values in proliferation to streptokinase (SK) and tetanus toxin (TT) than in healthy-controls. HIV-cases had lower IFN-γ and higher IL-5 production with pokeweed than healthy-controls (P < 0.01). However, IL-5 production of HIV-cases after TT stimulation was lower than in HIV-controls and healthy-controls. Total IgG and IgG1 levels were significantly higher in HIV-cases than in HIV-controls and healthy-controls. Also, IgM levels were significantly higher in HIV-cases than in healthy-controls. Nevertheless, IgG2 levels were significantly lower in HIV-cases and HIV-controls than in healthy-controls. The levels of specific Igs antipneumococcal capsular polysaccharide and TT were significantly lower in HIV-cases than in healthy-controls. HIV-patients with a previous state of severe-moderate immunosuppression normalizing their CD4+ counts have a incomplete immune reconstitution after HAART. Long-term consequences of this subclinical immune deficiency remain to be determined.     

Current perspectives on HER2 testing: a review of national testing guidelines.

Knowledge of HER2 status is a prerequisite when considering a patient's eligibility for Herceptin (trastuzumab) therapy. Accurate assessment of HER2 status is essential to ensure that all patients who may benefit from Herceptin are correctly identified. There are several assays available to determine HER2 status: the most common in routine clinical practice are immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Various factors can affect the results achieved with these assays, including the assay antibody/probe, the methodology and the experience of personnel. Many countries have implemented national testing guidelines in an attempt to standardize testing procedures and make results more accurate. These guidelines vary in the level of detail and the number of recommendations. This review looks at areas of consensus between the different national testing guidelines and highlights where errors may arise during the testing procedure. The key point underlined by this review is that whatever method is used to test for HER2 status, the technology must be validated first, and there must be regular internal and external quality control and quality assurance procedures.     

Histopathology training in Europe: a lesson for other specialties?

Critical shortages of trained histopathologists limit the capacity of cancer and other clinical services. A survey of histopathology training in 18 European countries conducted by the European Union of Medical Specialists Section of Pathology/European Board of Pathology revealed a considerable shortage of both trained and trainee histopathologists in several of the responding countries. Demographic data indicate a high preponderance of trained histopathologists over 55 years of age and a notable proportion of part-time personnel. Although the training capacity in some countries has been increased, the immediate future of histopathology and the clinical services dependent on the specialty is worrisome. The histopathology workload is growing, and, in some countries, recruitment of trainees is insufficient for future needs. To avert the serious consequences for dependent clinical specialties and their patients, there should be a concerted European action to promote and expand histopathology training.     

Mutations of CD40 ligand in two patients with hyper-IgM syndrome

Two patients with the X-linked form of the hyper-IgM syndrome have been studied. Both patients present: 1. Mutations in the CD40L gene (a nonsense point mutation that introduces a termination codon at the extracellular domain of the protein, and a deletion that eliminates exon 4 as consequence of an abnormal splicing). 2. Lack of CD40L expression on the lymphocyte surface after stimulation with ionomycin and PMA. 3. Altered lymphocytic proliferation in response to anti-CD3. 4. Hyper IgM, low IgG and IgA levels and neutropenia. One of the patients shows, in addition, low Natural Killer cell numbers and severe herpetic infections, which distinguishes this case from the common hyper-IgM syndrome phenotype. Finally, a hyper-IgM stable phenotype has been immortalized by Herpes virus Saimiri for the first time.     

Detection of serum antibodies to CagA and VacA and of serum neutralizing activity for vacuolating cytotoxin in patients with Helicobacter pylori-induced gastritis.

Thirty patients with dyspepsia, with histological diagnosis of gastritis, and with endoscopic diagnosis of peptic ulcer disease (PUD) (n = 13) or nonulcer dyspepsia (NUD) (n = 17) were admitted to the study. Helicobacter pylori vacuolating cytotoxin-producing strains (Tox+) were isolated from 14 (46.7%) patients, whereas non-cytotoxin-producing (Tox-) H. pylori strains were isolated from the remaining patients. Of 30 patients studied, 20 (66.7%) had serum cytotoxin neutralizing activity in vitro. Fourteen patients with Tox+ H. pylori strains showed serum cytotoxin neutralizing activity and serum immunoglobulin G (IgG) and IgA antibodies reactive with both 87-kDa H. pylori vacuolating cytotoxin (VacA) and 128-kDa cytotoxin-associated gene product (CagA) by immunoblotting using native enriched preparations of VacA and CagA proteins from H. pylori culture supernatants as the antigens. A 94-kDa antigen cross-reacting with the 87-kDa VacA protein could be demonstrated in culture supernatant with immune sera from humans and animals. All patients (n = 10) lacking serum neutralizing activity were also negative for IgG or IgA against VacA antigen, whereas 6 of the 10 patients showed IgG serum antibody responses against CagA antigen. The prevalence of antibodies to VacA and CagA antigens was significantly (P < 0.001) higher in patients with gastritis (20 and 26 patients for VacA and CagA, respectively, of 30 patients) than in H. pylori culture-negative controls (0 of 27 for both VacA and CagA) and in randomly selected blood donors (17 and 21 for VacA and CagA, respectively, of 120 subjects). All patients with PUD had antibodies to CagA, whereas 13 of 17 (76.5%) patients with NUD had anti-CagA antibodies. Serum IgG antibodies to VacA were present in 9 (69.2%) patients with PUD of 13 patients and in 11 (64.7%) patients with NUD of 17 patients. Anti-CagA antibodies seemed to correlate better with PUD than anti-VacA antibodies.