Multidrug-resistant cancer cells facilitate E1-independent adenoviral replication: impact for cancer gene therapy

Resistance to chemotherapy is responsible for a failure of current treatment regimens in cancer patients. We have reported previously that the Y-box protein YB-1 regulates expression of the P-glycoprotein gene mdr1, which plays a major role in the development of a multidrug resistant-tumor phenotype. YB-1 predicts drug resistance and patient outcome in breast cancer. Thus, YB-1 is a promising target for new therapeutic approaches to defeat multidrug resistance. In drug-resistant cancer cells and in adenovirus-infected cells YB-1 is found in the nucleus. Nuclear accumulation of YB-1 in adenovirus-infected cells is a function of the E1 region, and we have shown that YB-1 facilitates adenovirus replication. Here we report that E1A-deleted or mutant adenovirus vectors, such as Ad312 and Ad520, replicate efficiently in multidrug-resistant (MDR) cancer cells and induce an adenovirus cytopathic effect resulting in host cell lysis. Thus, replication-defective adenoviruses are a previously unrecognized vector system for a selective elimination of MDR cancer cells. Our work forms the basis for the development of novel oncolytic adenovirus vectors for the treatment of MDR malignant diseases in the clinical setting.     

Identification of candidate antigens for serologic detection of Helicobacter pylori-infected patients with gastric carcinoma

Helicobacter pylori colonizes the stomach of almost half the world population and is a causative agent of gastric carcinomas and duodenal ulcers. Only a small fraction of infected people will develop these severe illnesses and a predictive test to identify people at high risk would greatly benefit disease management. Our study aimed to identify conserved bacterial antigens that may be useful for the development of such a diagnostic test. High-resolution immunoproteomics by 2-dimensional electrophoresis of H. pylori 26695 proteins was carried out with sera from infected patients with either duodenal ulcer (n=30) or gastric carcinoma (n=30), 2 clinically divergent conditions. According to their antigen recognition patterns clear groups of patients were identified. Although this classification did not correspond to the clinical status, it may be correlated to other bacterial or host factors that influence the outcome of infection. In general antigen recognition patterns were found to be highly variable, however by utilizing powerful image analysis and statistical tests the recognition of 14 antigenic protein species was found to differ significantly (p<0.01) between both diseases. Particular protein species of GroEL, HyuA, GroES and AtpA appear to be useful surrogate markers for gastric carcinoma detection and consequently should be considered for further prospective studies to assess their predictive value. For one protein species of AtpA, evidence was found that different post-translational modifications may confer different immunogenicities.     

Microsatellite instability mutator phenotype in hepatocellular carcinoma in non-alcoholic and non-virally infected normal livers

Microsatellite instability (MSI) seems to be a rare event in hepatocarcinogenesis and might actually be associated with the progression of hepatocellular carcinoma (HCC) in which the liver is often the site of chronic hepatitis or cirrhosis. The aim of this work was to define the MSI phenotype in HCC affecting exclusively normal livers to avoid slippage errors due to cirrhosis. One hundred and sixty-four patients with HCC affecting non-cirrhotic livers were operated on in our hospital between 1984 and 2001. We analyzed 37 patients selected for low alcohol consumption and the absence of HBV or HCV infection. All the livers were histologically normal. MSI was analyzed according to the criteria defined during the conference consensus workshop for colorectal cancer. High MSI (MSI-H > 30%) was found in 6 (16%) and low MSI (MSI-L < 30%) in 10 (27%) of the 37 HCCs. None of the 10 microsatellite markers tested were altered in the remaining 21 tumors (57%). Immunohistochemistry showed that normal amounts of hMLH1 and hMSH2 were present both in MSI-H and in MSI-L HCCs. MSI-H was significantly associated with more aggressive histological tumor features and a shorter median delay before recurrence. Thus, we have found a small subgroup of HCC tumors which can be considered as a new clinical/histological entity.     

High Ep-CAM Expression is Associated with Poor Prognosis in Node-positive Breast Cancer

Previous studies in small series of patients with invasive breast cancer suggested a prognostic value of Ep-CAM overexpression in primary tumor tissue. To corroborate these findings, we performed a retrospective analysis of Ep-CAM expression using a tissue microarray containing tissue specimens from a large patient set. Ep-CAM expression was evaluated by immunohistochemistry in breast cancer tissue from 1715 patients with documented raw survival data. High level Ep-CAM expression (overexpression) was found in 41.7% of tumor samples, low level expression was found in 48.0% and no expression in 10.3% of tumor samples. Ep-CAM expression predicted poor overall survival in this patient cohort (p < 0.0001). Overall survival decreased significantly with increasing Ep-CAM expression. However, in this patient sample Ep-CAM expression was not an independent prognostic marker by multivariate analysis. Subgroup analysis revealed that Ep-CAM expression was a prognostic marker in node-positive (p < 0.0001) but not in node-negative (p = 0.58) breast cancer patients. Intriguingly, Ep-CAM expression was predictive for a dismal prognosis in patients receiving adjuvant cytotoxic (p = 0.03) or hormonal therapy (p < 0.0001) but not in untreated patients (p = 0.41). In summary, this study provides strong evidence that expression of Ep-CAM is a powerful marker of poor prognosis in node-positive invasive breast carcinoma and a potential predictive marker of sensitivity to adjuvant hormonal and/or cytotoxic treatment modalities.     

Molecular genetics and its clinical relevance

Molecular genetic methods such as fluorescence in situ hybridization and DNA sequencing have greatly improved our understanding of pathogenic events and prognostic markers in chronic lymphocytic leukemia (CLL). There are genomic aberrations detected in over 80% of CLL cases, and genes potentially involved in the pathogenesis were identified with ATM in a subset of cases with 11q deletion and p53 in cases with 17p13 deletion. Genetic subgroups with distinct clinical features have been identified, such as 11q deletion, which is associated with marked lymphadenopathy and rapid disease progression, whereas 17p deletion predicts for treatment failure with alkylating agents, fludarabine, and short survival times. There is mutation status of the VH genes that allows the separation into patients with long (mutated VH) or short (unmutated VH) survival times. V-gene usage, VDJ structure, and gene expression differences in the two subgroups allow insights into differential pathogenic mechanisms and provide further prognostic information (V3-21 usage, ZAP-70 expression). The VH mutation status and genomic abnormalities have been shown to be of independent prognostic value in multivariate analysis, seem to allow outcome predication irrespective of the clinical stage, and may therefore allow a risk assessment for individual patients early in the course of their disease.     

Age-related changes in the glycation of human aortic elastin

Non-enzymatic glycation of proteins is a consequence of hyperglycemia in diabetes and correlates with aging. The aim of the study was to investigate age-related changes in the glycation of human aortic elastin in healthy subjects by two approaches: (1) assessment by fluorescence method of formed in vivo advanced glycation end products (AGEs) of elastins, purified from human aortas, obtained from different age groups; (2) in vitro glycation of elastins from different age groups and investigation of their capacity to form early (by colorimetric nitroblue tetrazolium method) and AGEs (fluorescence method). Human insoluble elastins were prepared from macro- and microscopic unaltered regions of thoracic aortas, obtained from 68 accident victims, distributed in 15 age-groups, using the method of Starcher and Galione. Soluble alpha-elastins were obtained by the method of Partridge et al. The direct assessment of Maillard reaction related fluorescence in the age groups showed increase of the fluorescence with age. The 'young' elastin had the highest capacity to form both fructosamine and AGEs under glycation in vitro. The glycation of 'old' elastin did not increase markedly during the incubation. These results are consistent with the interpretation that because of its long biological half-life, elastin is susceptible to the slow process of glycation and the following modifications would contribute to the age-related changes of connective tissue.     

Clinical, hormonal and magnetic resonance imaging (MRI) predictors of transsphenoidal surgery outcome in acromegaly

OBJECTIVE: Progress in the treatment of acromegaly with drugs is making it necessary to improve the prediction of the outcome of transsphenoidal surgery. DESIGN: We evaluated clinical, hormonal and radiologic predictors based on magnetic resonance imaging (MRI) of surgical outcome in patients with acromegaly. METHODS: This retrospective analysis included 125 consecutive patients investigated for acromegaly in a single endocrine unit since the use of MRI imaging began (1988). Eighty-three of these patients (50 women) underwent transsphenoidal surgery and were investigated before and after surgery in our department. A neuroradiologist unaware of the surgical outcome analyzed the results of pituitary gland MRI investigations. RESULTS: Surgical remission rates were 44%, 43%, 61% and 59% based on mean basal GH concentration under 2.5 microg/l, GH/oral glucose tolerance test (OGTT) of <1 microg/l, GH/OGTT of <2 microg/l or IGF-I concentration normal for age and sex respectively. In univariate logistic regression analysis with IGF-I concentration used as the criterion for cure, young age (P<0.001), high IGF-I concentration before surgery (P<0.01), high basal GH concentration before surgery (P<0.02), and high nadir GH/OGTT before surgery (P=0.03) were predictors of poor outcome. The following results in standardized MRI analysis were associated with a higher probability of not being cured: adenoma greater than 15 mm in diameter (P<0.02), infrasellar extension (P=0.04), suprasellar extension (P<0.005) and invasive adenoma (0.02) according to MRI staging. MRI analysis of the intracavernous extension showed that stages above B2 (possible sinus extension with sign of invasion of the space below the carotid artery) were associated with a lower probability of postoperative normal GH plasma levels (P=0.01). In multivariate analysis, age, preoperative hormonal levels and adenoma size remained the major predictors of surgical outcome. CONCLUSIONS: This report provides the first evidence that detailed MRI analysis of adenoma size, location and potential invasion, together with preoperative clinical and hormonal parameters, can be used for the prediction of hormonal outcome after transsphenoidal surgery for acromegaly.     

The future of general internal medicine

The Society of General Internal Medicine asked a task force to redefine the domain of general internal medicine. The task force believes that the chaos and dysfunction that characterize today's medical care, and the challenges facing general internal medicine, should spur innovation. These are our recommendations: while remaining true to its core values and competencies, general internal medicine should stay both broad and deep—ranging from uncomplicated primary care to continuous care of patients with multiple, complex, chronic diseases. Postgraduate and continuing education should develop mastery. Wherever they practice, general internists should be able to lead teams and be responsible for the care their teams give, embrace changes in information systems, and aim to provide most of the care their patients require. Current financing of physician services, especially fee-for-service, must be changed to recognize the value of services performed outside the traditional face-to-face visit and give practitioners incentives to improve quality and efficiency, and provide comprehensive, ongoing care. General internal medicine residency training should be reformed to provide both broad and deep medical knowledge, as well as mastery of informatics, management, and team leadership. General internal medicine residents should have options to tailor their final 1 to 2 years to fit their practice goals, often earning a certificate of added qualification (CAQ) in special generalist fields. Research will expand to include practice and operations management, developing more effective shared decision making and transparent medical records, and promoting the close personal connection that both doctors and patients want. We believe these changes constitute a paradigm shift that can benefit patients and the public and reenergize general internal medicine.