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[Eosinophilia and hepatopathy].

We present the case of a 70-year old Patient with diffuse abdominal pain, severe eosinophilia, and increased liver parameters hospitalized for further evaluation. An idiopathic hypereosinophilic syndrome was postulated and the patient was treated with highdose methylprednisolone with rapid normalisation of the eosinophil numbers and decrease of the liver parameters. Later on strongyloidosis could be diagnosed (positive ELISA Test) as the cause of eosinophilia, and the patient was successfully treated with mebendazole. Blood eosionophilia most commonly reflects an allergic, infectious or neoplastic process; increased blood and/or tissue eosinophilia range in severity from self-limited to life-threatening conditions. Strongyloides infection can persist for years without prominent symptoms and should be suspected in any patient with unexplained eosinophilia.

Abdominal Pain↗

Benign mucinous metaplasia of the penis. A lesion resembling extramammary Paget's disease.

Benign mucinous metaplasia in the surface epithelium of the genital area is rare and has only been reported once in the vulva. A unique case of benign mucinous metaplasia of the prepuce in a 65-year-old man is reported here. The lesion measured 0.6 cm, was located in the mucous surface of the foreskin, and showed acid mucin containing cells. We regard benign mucinous metaplasia as a reactive rather than a neoplastic process. The main lesions to be considered in the differential diagnosis are mucinous syringometaplasia, extramammary Paget's disease, cutaneous squamous cell carcinoma in situ with mucinous metaplasia, superficial spreading malignant melanoma, and epidermotropic metastasis. The confinement of mucin-containing cells to the epidermis, the absence of nuclear atypia, the basal orientation of the nuclei, the predominant location of the cells in the upper layers of the epithelium, and the fact that the mucinous cells are replacing the squamous epithelium rather that infiltrating it, all assist in recognizing mucinous metaplasia of the penis as a specific and benign entity.

Aged↗

CD8+ chronic lymphocytic leukemia: an extensive characterization of a bizarre hybrid neoplasia.

Atypical chronic lymphocytic leukemia (CLL) expressing the CD8 antigen have a frequency of less than 0.5% of all cases, however, they are not yet been fully characterized. Herein a CD8+ CLL case was extensively studied. Besides the classical CLL antigen expression, an unusual presence of surface markers such as CD11c, CD56, and CD154 was observed. Moreover, gene expression of chemokine receptors belonging to the CCR family were clearly evidenced as well as mRNA for both, Th1 and Th2 cytokines. Likewise, granzyme A, B and perforin gene expression, cytotoxic T cell or NK enzymes were found. The intricate profile of membrane molecules and gene expression suggest that it could be favorable, rather than deletereous, for the maintainance of the neoplastic process.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Similarity of protein encoded by the human c-erb-B-2 gene to epidermal growth factor receptor.

A novel v-erb-B-related gene, c-erb-B-2, which has been identified in the human genome, maps to human chromosome 17 at q21 (ref. 40), and seems to encode a polypeptide with a kinase domain that is highly homologous with, but distinct from, that of the epidermal growth factor (EGF) receptor. The c-erb-B-2 gene is conserved in vertebrates and it has been suggested that the neu gene, detected in a series of rat neuro/glioblastomas, is, in fact, the rat c-erb-B-2 gene. Amplification of the c-erb-B-2 gene in a salivary adenocarcinoma and a gastric cancer cell line MKN-7 suggests that its over-expression is sometimes involved in the neoplastic process. To determine the nature of the c-erb-B-2 protein, we have now molecularly cloned complementary DNA for c-erb-B-2 messenger RNA prepared from MKN-7 cells. Its sequence shows that the c-erb-B-2 gene encodes a possible receptor protein and allows an analysis of the similarity of the protein to the EGF receptor and the neu product. As a consequence of chromosomal aberration in MKN-7 cells, a 4.6-kilobase (kb) normal transcript and a truncated 2.3-kb transcript of c-erb-B-2 are synthesized at elevated levels. The latter transcript presumably encodes only the extracellular domain of the putative receptor.

Amino Acid Sequence↗

Novel source of 1,2-diacylglycerol elevated in cells transformed by Ha-ras oncogene.

Genes involved in the transduction of signals required for normal cell proliferation commonly appear to be subverted in the neoplastic process. One such group is the highly conserved family of ras genes, which have been detected as transforming genes in a wide variety of naturally occurring tumours. By analogy with other known G proteins, the p21 proteins encoded by ras genes may act as regulatory proteins in the transduction of signals that lead to DNA synthesis. A major pathway involved in the DNA synthesis induced by growth factors is mediated by phosphatidylinositol turnover: cleavage of phosphoinositides by phospholipase C produces 1,2-diacylglycerol, and inositol phosphates. The former acts as an essential cofactor for protein kinase C (ref. 4), and inositol-(1,4,5)-triphosphate mobilizes Ca2+ from non-mitochondrial intracellular stores. We demonstrate a reproducible increase in 1,2-diacylglycerol, in the absence of a detectable increase in inositol phosphates, in transformed cells containing Ha-ras oncogenes and with different membrane targeting signals for the ras p21 protein. These findings suggest that a source other than phosphoinositides exists for the generation of 1,2-diacylglycerol and that the Ha-ras oncogene specifically activates this novel pathway for 1,2-diacylglycerol production.

Animals↗

Molecular profiling of human cancer.

Traditionally, tumours have been categorized on the basis of histology. However, the staining pattern of cancer cells viewed under the microscope is insufficient to reflect the complicated underlying molecular events that drive the neoplastic process. By surveying thousands of genes at once, using DNA arrays, it is now possible to read the molecular signature of an individual patient's tumour. When the signature is analysed with clustering algorithms, new classes of cancer emerge that transcend distinctions based on histological appearance alone. Using DNA arrays, protein arrays and appropriate experimental models, the ultimate goal is to move beyond correlation and classification to achieve new insights into disease mechanisms and treatment targets.

Gene Expression Profiling↗

Cell kinetics of urethane-induced murine pulmonary adenomas: III. Implications of the disparity between the rates of entry into DNA synthesis and into mitosis.

Metaphase arrest by vincristine in urethane-induced murine pulmonary adenomas became linear after an interval of 60 min. The rate of entry into metaphase was 0-191%/h, which was considerably less than the 1%/h for the rate of entry into DNA synthesis obtained previously by double labelling. The duration of prophase plus metaphase was calculated to be 1-7 h. A growth fraction of 9% and a cell-loss factor of 52% were derived. The disparity between rates of entry into DNA synthesis and into metaphase was investigated by microdensitometry on Feulgen-stained squash preparations of tumours of varying ages. Tne DNA profiles showed an increasing frequency of hyperdiploid nuclei with age. Circumstantial evidence for polyploidy was provided by the presence of many binucleate cells in the tumours. By analogy with the liver, these cells may well represent a stage in the development of polyploidy, and the possible relevance of these findings to the neoplastic process is considered.

Adenoma↗

Serum retinol level in patients with colorectal premalignant and malignant lesions.

Serum retinol levels were determined by a fluorometric method in patients with colorectal cancer or polyps and those with inflammatory bowel disease. Serum retinol levels in patients with benign or malignant colorectal polyps and stage B cancer (modified Dukes' classification) were similar to those found in controls. By contrast, serum retinol levels were significantly lower in patients with Dukes' stage C or D. Among cancer patients that were followed after surgical treatment serum retinol levels did not differ significantly from those found in controls. Patients who died of metastases during follow-up possessed very low serum retinol levels. These findings suggest that a decreased serum retinol level in cancer patients is a consequence rather than a precursor of the neoplastic process. Furthermore, this study suggests that the marked decrease in serum retinol level might be an indicator of poor prognosis in colorectal cancer patients after surgery.

Adult↗

Loss of cell-cell and cell-matrix adhesion molecules in colorectal cancer.

Adhesion molecules are thought to play a vital role in the induction and maintenance of tissue differentiation and their loss or down-regulation has been implicated in the neoplastic process. Recent studies have shown that the morphoregulatory activities are a consequence of interactive processes between several cell adhesion molecules rather than the function of a single molecule. Therefore, we have investigated a panel of adhesion molecules including members of the integrin, cadherin and immunoglobin superfamily in colorectal cancer. Twenty-eight consecutive colorectal adenocarcinomas were stained using an avidin-biotin indirect immunoperoxidase technique. Our results showed a consistent loss of the alpha 2 and beta 1 integrin subunits (21/28 = 75% and 22/28 = 78.6% respectively) and a decrease in expression of E-cadherin in 5/5 poorly differentiated adenocarcinomas. Carcinoembryonic antigen expression was preserved but with basolateral accentuation seen in tumours. There was no statistical correlation with Dukes' stage. These results provide further evidence that in colorectal cancer there is a widespread deregulated expression of cell-cell and cell-matrix adhesion molecules. Changes in the expression and function of adhesion molecules which regulate growth and differentiation may play a role in the behaviour of colorectal cancer.

Adenocarcinoma↗

Epstein-Barr virus and carcinomas: rare association of the virus with gastric adenocarcinomas.

We have analysed 174 gastric carcinomas from the United Kingdom and from Japan for the presence of Epstein-Barr virus (EBV) using in situ hybridisation for the small EBV-encoded nuclear RNAs (EBERs). EBV was detected in the tumour cells in all of six undifferentiated gastric carcinomas with prominent lymphoid stroma (undifferentiated carcinomas of nasopharyngeal type, UCNT) but only in three of the remaining 168 typical gastric adenocarcinomas (1.8%). No differences were observed between the British and the Japanese cases. One case with an EBV-positive UCNT showed adjacent areas of EBV-negative typical adenocarcinoma. It is uncertain whether these patterns represent two independent carcinomas or whether they are the result of heterogeneous EBV infection in a single tumour. In the remaining EBV-positive carcinomas, viral transcripts were detected in virtually all tumour cells, indicating that EBV infection must have taken place early in the neoplastic process and suggesting that the virus is likely to be of pathogenetic significance for the virus-associated tumours. Immunohistology demonstrated absence of detectable levels of the EBV-encoded latent membrane protein, LMP1, and nuclear antigen, EBNA2. The BZLF1 protein which induces the switch from latent to lytic infection was demonstrated in a small proportion of the tumour cells in three cases. The close association of EBV with undifferentiated gastric carcinomas compared to the variable association with gastric adenocarcinomas suggests fundamentally different roles for the virus in the aetiology of these two malignancies.

Adenocarcinoma↗

The cancer stem cell hypothesis: a work in progress.

There is a growing body of evidence that supports the idea that malignant tumors are initiated and maintained by a population of tumor cells that share similar biologic properties to normal adult stem cells. This model, the cancer stem cell (CSC) hypothesis, is based on the observation that tumors, like adult tissues, arise from cells that exhibit the ability to self-renew as well as give rise to differentiated tissue cells. Although the concept of the CSC is not entirely new, advances made over the past two decades in our understanding of normal stem cell biology in conjunction with the recent application of these concepts to experimentally define CSCs have resulted in the identification of CSCs in several human malignancies.

Adult Stem Cells↗

Molecular genetics of human prostate cancer.

Multiple factors contribute to the high incidence and prevalence of prostate cancer including race, ethnicity, diet, environment, widespread awareness through prostate-specific antigen screening and genetics. Linkage analysis has identified several candidate sites for hereditary prostate cancer gene loci. Molecular studies have also identified genes that are frequently altered in sporadic prostate cancer. It appears that due to the heterogeneity of prostate cancer, multiple genes may be involved in the neoplastic process.

Chromosomal Instability↗

Promoter methylation profiles of tumor suppressor genes in intrahepatic and extrahepatic cholangiocarcinoma.

Recent studies indicate that tumor suppressor genes can be epigenetically silenced through promoter hypermethylation. To further understand epigenetic alterations in cholangiocarcinoma, we have studied the methylation profiles of 12 candidate tumor suppressor genes (APC, E-cadherin/CDH1, MGMT, RASSF1A, GSTP, RAR-beta, p14ARF, p15INK4b, p16INK4a, p73, hMLH1 and DAPK) in 72 cases of cholangiocarcinoma, including equal number cases of intrahepatic cholangiocarcinoma and extrahepatic cholangiocarcinoma. A total of 10 cases of benign biliary epithelia were included as controls. The methylation status of tumor suppressor genes was analyzed using methylation-specific PCR. We found that 85% of all cholangiocarcinomas had methylation of at least one tumor suppressor gene. The frequency of tumor suppressor gene methylation in cholangiocarcinoma was: RASSF1A (65%), p15INK4b (50%), p16INK4a (50%), APC (46%), E-cadherin/CDH1 (43%), p14(ARF) (38%), p73 (36%), MGMT (33%), hMHL1 (25%), GSTP (14%), RAR-beta (14%) and DAPK (3%). Although single tumor suppressor gene methylation can be seen in benign biliary epithelium, methylation of multiple tumor suppressor genes is only seen in cholangiocarcinoma. About 70% (50/72) of the cholangiocarcinomas had three or more tumor suppressor genes methylated and 52% (38/72) of cases had four or more tumor suppressor genes methylated. Concerted methylation of multiple tumor suppressor genes was closely associated with methylation of RASSF1A, p16 and/or hMHL1. Methylation of RASSF1A was more common in extrahepatic cholangiocarcinoma than intrahepatic cholangiocarcinoma (83 vs 47%, P=0.003) while GSTP was more frequently seen in intrahepatic compared to extrahepatic cholangiocarcinoma (31 vs 6%, P=0.012). Our study indicates that methylation of promoter CpG islands of tumor suppressor genes is a common epigenetic event in cholangiocarcinoma. Based on distinct methylation profiles, intrahepatic cholangiocarcinoma and extrahepatic cholangiocarcinoma are two closely related but biologically unique neoplastic processes. Taking advantage of the unique concurrent methylation profile of multiple genes in cholangiocarcinoma may facilitate the distinction of cholangiocarcinoma from benign biliary epithelium in clinical settings.

Bile Duct Neoplasms↗

Distinct spatial expression patterns of AP-2alpha and AP-2gamma in non-neoplastic human breast and breast cancer.

Although transcription factors AP-2alpha and AP-2gamma have been implicated in the control of estrogen receptor (ER) and ErbB-2, their impact for breast cancer is still controversial. To better understand the role of AP-2 proteins in mammary neoplasia, the analysis of their spatial expression pattern in normal breast and breast cancer is required. A total of 51 specimens of female breast cancer patients and a tissue microarray containing 93 additional female breast cancer cases were immunohistochemically stained for AP-2alpha, AP-2gamma, ER and ErbB-2. In 70 cases of the tissue microarray, survival data comprising a period of up to 30 years were present. In non-neoplastic breast tissue, AP-2alpha was expressed in the inner glandular cell layer while AP-2gamma was expressed in the outer myoepithelial cell layer. Ductal carcinoma in situ revealed strongly AP-2alpha-positive tumor cells surrounded by a layer of AP-2gamma-positive myoepithelial cells. In invasive carcinoma, expression of AP-2alpha and AP-2gamma was variable. High expression of ER and AP-2alpha showed better survival rates than low expression of these markers. AP-2gamma expression had no effect on survival. These results for the first time reveal a distinct spatial expression pattern of AP-2alpha and AP-2gamma in normal breast and in ductal carcinoma in situ with specific AP-2gamma expression in myoepithelium. High ER and AP-2alpha expression in invasive breast cancer showed favorable survival rates. Therefore, AP-2alpha expression seems to be associated with better prognosis of breast cancer. AP-2gamma expression has no influence on survival reflecting that myoepithelial cells are not involved in the neoplastic process.

Actins↗

Inflammation and cancer.

Recent data have expanded the concept that inflammation is a critical component of tumour progression. Many cancers arise from sites of infection, chronic irritation and inflammation. It is now becoming clear that the tumour microenvironment, which is largely orchestrated by inflammatory cells, is an indispensable participant in the neoplastic process, fostering proliferation, survival and migration. In addition, tumour cells have co-opted some of the signalling molecules of the innate immune system, such as selectins, chemokines and their receptors for invasion, migration and metastasis. These insights are fostering new anti-inflammatory therapeutic approaches to cancer development.

Animals↗

Mechanisms of disease: The pathogenesis of pituitary tumors.

Pituitary tumors exhibit a spectrum of biology, with variable growth and hormonal behaviors. They therefore provide an opportunity to examine pathogenetic mechanisms that underlie the neoplastic process. These include alterations in hormone regulation, growth-factor stimulation, cell-cycle control and cell-stromal interactions that result from genetic mutations or epigenetic disruption of gene expression. Mouse models have validated the roles of these alterations, which can be targets for the development of therapies that can manage these lesions. These therapies are increasingly recognized as critical for quality of life.

Adenoma↗

Variation in RNA expression and genomic DNA content acquired during cell culture.

Specific chromosomal abnormalities are increasingly recognised to be associated with particular tumour subtypes. These cytogenetic abnormalities define the sites of specific genes, the alteration of which is implicated in the neoplastic process. We used comparative genomic hybridisation (CGH) to examine DNA from different breast and ovarian cancer cell lines for variations in DNA sequence copy number compared with the same normal control. We also compared different sources of the MCF7 breast line by both CGH and cDNA expression arrays. Some of the differences between the subcultures were extensive and involved large regions of the chromosome. Differences between the four subcultures were observed for gains of 2q, 5p, 5q, 6q, 7p, 7q, 9q, 10p, 11q, 13q, 14q, 16q, 18p and 20p, and losses of 4q, 5p, 5q, 6q, 7q, 8p, 11p, 11q, 12q, 13q, 15q, 19p, 19q, 20p, 21q, 22q and Xp. However, few variations were found between two subcultures examined, 5 months apart, from the same initial source. The RNA arrays also demonstrated considerable variation between the three different subcultures, with only 43% of genes expressed at the same levels in all three. Moreover, the patterns of the expressed genes did not always reflect our observed CGH aberrations. These results demonstrate extensive genomic instability and variation in RNA expression during subculture and provide supportive data for evidence that cell lines do evolve in culture, thereby weakening the direct relevance of such cultures as models of human cancer. This work also reinforces the concern that comparisons of published analyses of cultures of the same name may be dangerous.

Breast Neoplasms↗

Autoantibodies to endostatin in patients with breast cancer: correlation to endostatin levels and clinical outcome.

Circulating autoantibodies to self-antigens overexpressed by cancer cells are common in cancer patients. As specific proteins are expressed during neoangiogenesis, a similar phenomenon might occur with particular antigens of tumour vessels. Collagen XVIII, from which endostatin is cleaved, is highly expressed in the perivascular basement membrane of tumour-associated blood vessels and autoantibodies to endostatin have been reported in cancer patients. The present study analyses the incidence of naturally occurring autoantibodies to endostatin in the sera of breast cancer patients and their relation to endostatin serum levels and patient clinical outcome. Serum samples from 36 patients with localised breast cancer and 59 patients with a fully documented history of metastatic breast cancer were used. The immunoreactivity of serum samples was tested against purified recombinant human endostatin and endostatin levels were determined by immunoassay. We could detect anti-endostatin antibodies in the sera of 66% of the patients with localised disease and 42% of the patients with metastatic disease (P=0.03). There was no correlation between the presence of antibodies to endostatin and circulating levels of endostatin. The detection of autoantibodies to endostatin was associated with better prognosis in metastatic breast cancer patients (median survival time: 20 vs 8 months, P = 0.03), as was the presence of low levels of serum endostatin (median survival time: 20 vs 9 months, P = 0.007). These results show that a natural immune reaction against endostatin can occur in breast cancer patients. This could have important therapeutic implications with regard to endostatin therapy and raises the question of a possible role of this humoral reaction against endostatin in the neoplastic process.

Adult↗