Tumour angiogenesis and C-myc expression in breast carcinomas.

Angiogenesis in tumors has been widely studied and has been considered to be a prognostic factor particularly in breast carcinomas. The myc family of proto oncogenes has shown an amplification in breast carcinomas. The aim of this study was to assess MVD (micro vessel density) and the expression of c-myc in invasive breast carcinomas. Formalin fixed, routinely processed, paraffin embedded tissue was stained with H&E for classification and grading according to the Nottingham modification of Bloom and Richardson criteria. Immunohistochemical staining using primary antibody against F VIII antigen and anti C-myc were carried out. LSAB method was employed with AEC as chromogen and Gill's Haematoxylin as counter stain. Micro vessels were counted and positivity indicated by a cherry red staining in the cytoplasm of the tumour cells. Grades I, II and III showed 12.22 %, 20.9% and 24.5 % positivity of micro vessel density (MVD). Fifty percent of Grade 1, 69.2 % of Grade II and 24.5 % of Grade III tumours expressed c-myc proteins. In our study we found a positive association between tumour grade and micro vessel density, signifying a poor prognosis for tumours with high MVD. C-myc expression also showed a positive association with increasing grade.

Multidrug resistance 1 gene expression in Indian patients with gastric carcinoma.

BACKGROUND: Gastric carcinoma is frequently refractory to chemotherapy. The multidrug resistance 1 gene (MDR1) encodes for a protein (p-glycoprotein) that functions as a drug efflux pump and thus contributes to resistance to chemotherapeutic agents. METHODS: We studied gastric tissues from 28 patients with gastric cancer for MDR1 expression, using immunohistochemistry. RESULTS: Sixteen (57%) of 28 cases showed MDR1 expression. Sections of normal mucosa away from the tumor showed perinuclear staining for MDR1 in surface epithelial cells, whereas tumor cells showed diffuse cytoplasmic positivity. CONCLUSIONS: Over one half of gastric carcinoma specimens at our center show MDR1 gene expression.

The Epstein Barr virus and gastric carcinoma.

The Epstein Barr Virus (EBV) is one of the viruses implicated in the pathogenesis of malignant tumors. Its association with Burkitt's Lymphoma, nasopharyngeal carcinoma and certain cases of Hodgkin's lymphoma is well known. More recently this virus has been found to be associated with gastric carcinoma. Studies on this association, in our country are lacking. We have studied 37 cases of carcinoma using immunohistochemistry for LMP1 protein. Most workers have found an expression of latency type I antigens in gastric adenocarcinomas, with only a few cases being LMP1 positive. In the 37 cases studied by us, 24.14% of cases were positive for LMP1. LMP1 is known to have oncogenic properties. In addition, it has been demonstrated earlier that the EBV particles in gastric carcinoma are monoclonal. These two factors support a pathogenetic role for EBV in gastric carcinoma.

P 53 and PCNA in Non Hodgkin's lymphoma--an immunohistochemical evaluation.

P 53 positivity and PCNA labelling index were studied in 50 cases of node based Non Hodgkin's lymphomas, P 53 positivity was observed in a spectrum of these disorders, suggesting that P 53 mutations play a role in the genesis of these tumours. P 53 positivity incresed from low through intermediate to high grade tumours and thus may be of prognostic value in these lesions. PCNA labelling index (LI) was higher in high grade tumours. P 53 and PCNA immunoreactivity showed a relationship in that PCNA LI was seen to be more than 30% in P 53 positive tumours. P 53 positivity appears to be related to the subtype and proliferation rate of NHL.

Study of association of Epstein Barr-virus with Hodgkin's disease.

Epstein Barr-Virus (EBV) is a lymphotropic herpes virus, well recognised for its oncogenic properties. In recent years substantial evidence has accumulated supporting a role for EBV in the pathogenesis of Hodgkin's disease. The epidemiologic and histologic features of Hodgkin's disease (HD) have long indicated a possible infective cause. Our study involves the detection of the EBV encoded latent membrane protein 1 (LMP-1) in 45 cases of Hodgkin's disease using immunohistochemical methods. In this study we detected LMP-1 positivity in the Reed-Sternberg and Hodgkin's cells in 31% of cases of HD. In mixed cellularity the positivity was 21.7% while nodular sclerosis exhibited positivity of 50% of the cases. The lymphocyte depletion subtype showed 100% positivity. All cases of lymphocyte predominance and the single unclassified case were negative for LMP. The demonstration of LMP-1 in Hodgkin's disease has important implications since it is one of the latent gene products which produces B Lymphocyte transformation.

Protein C levels in ischaemic heart disease.

Protein C is a circulating glycoprotein with anticoagulant properties. Functional and immunological levels of protein C were determined in 34 cases of ischaemic heart disease and 12 healthy age-matched controls. The sensitive colorimetric assay was used to determine the functional levels and ELISA for antigenic levels. Mean protein C activity and antigenic levels were found to be elevated in these patients as compared to controls. Protein C levels in the three individual subgroups-acute myocardial infarction, previous myocardial infarction and chronic stable angina pectoris-were also raised as compared to controls. The elevation was significant in the case of the acute myocardial infarction group. These results further support the hypothesis that the body synthesises increased amounts of protein C in ischaemic heart disease to compensate for the hypercoagulable state that exists in this disorder, thus playing a protective role.

Lectin binding patterns in benign and malignant lesions of the breast.

The binding patterns of a panel of eight lectins were studied in twenty eight breast lesions, consisting of ten cases of fibroadenoma, three cases of cystosarcoma phyllodes, five cases of fibrocystic disease and ten cases of infiltrating duct carcinoma by light microscopy. The eight lectins viz. PNA, WGA, RCA, SBA, UEA I, LTA, LCA and Con A were tested on paraffin sections using the Avidin Biotin Peroxidase Complex technique. PNA, RCA and UEA I showed a consistent positivity in benign and malignant lesions. The binding was localised mainly along the apices of mammary ductal epithelial cells in the benign lesions. In contrast, the malignant cells showed a considerable variation in staining patterns like diffuse cytoplasmic, membranous, and vacuolar. No definite correlation was seen between the intensity of binding and the histological grade in infiltrating duct carcinoma except in the case of Con A which was seen to bind more intensely to poorly differentiated tumours. The diagnostic significance of these patterns have been discussed.