Lipid-bound sugars in Rhizobium meliloti

Incubation of an enzyme preparation of Rhizobium meliloti with labeled uridine diphosphate glucose led to the formation of radioactive substances soluble in organic solvents. These substances are probably polyprenyl diphosphate saccharides. They behaved like these on treatment with ammonia or with hot phenol and were decomposed by heating for 10 min at pH 2 yielding a mono- and a disaccharide. The monosaccharide was identified as galactose by paper chromatography. The disaccharide gave glucose and galactose by acid hydrolysis. Following reduction with borohydride it yielded glucose and galactitol. After treatment with periodate followed by paper chromatography only galactose was detectable. The disaccharide was hydrolyzed by β- but not by α-glucosidase. Therefore the disaccharide is glucosyl β1-3-galactose.     

Localization of decorin gene expression in normal human breast tissue and in benign and malignant tumors of the human breast

The small extracellular matrix proteoglycan decorin which possesses a potent antitumor activity has been shown to be present in various amounts in the stroma of several tumors including those of the breast. Regarding decorin in breast malignancies the published data are conflicting, i.e., whether breast cancer cells express it or not. Here, we first compared decorin gene expression levels between healthy human breast tissue and selected types of human breast cancer using GeneSapiens databank. Next, we localized decorin mRNA in tissue specimen of normal human breast, intraductal breast papillomas and various histologic types of human breast cancer using in situ hybridization (ISH) with digoxigenin-labeled RNA probes for decorin. We also examined the effect of decorin transduction on the behavior of cultured human breast cancer MCF7 cells. Analysis of GeneSapiens databank revealed that in various human breast cancers decorin expression is significant. However, ISH results clearly demonstrated that human breast cancer cells independently of the type of the cancer do not express decorin mRNA. This was also true for papilloma-forming cells of the human breast. Indeed, decorin gene expression in healthy human breast tissue as well as in benign and malignant tumors of human breast was shown to take place solely in cells of the original stroma. Decorin transduction using decorin adenoviral vector in decorin-negative MCF7 cells resulted in a significant decrease in the proliferation of these cells and changed cell cohesion. Decorin-transduced MCF7 cells also exhibited increased apoptosis. In conclusion, our study shows that in human breast tissue only cells of the original stroma are capable of decorin gene expression. Our study also shows that transduction of decorin in decorin-negative human breast cancer cells markedly modulates the growth pattern of these cells.     

Neurospecific proteins in human malignant brain tumors

The content of neurospecific proteins S-100, GFA and D2 was measured in malignant cerebral tumors by electrophoresis with the use of monospecific antisera. Concomitant measurement of proteins S-100 and GFA is a more reliable diagnostic criterion as to the tumor histogenesis than study of each protein alone. D2 protein appeared to be the most stable specific marker.     

Expression of the apoptosis-inducing ligands FasL and TRAIL in malignant and benign human breast tumors

Apoptosis-inducing ligands such as Fas ligand (FasL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) have been found to play an important role in cell regulation. Different malignant tumors show an altered expression of these ligands and their respective receptors compared to normal tissues. The purpose of this study was therefore to investigate expression of TRAIL, FasL, and its receptor Fas on protein and mRNA levels in breast carcinomas (n=40), fibroadenomas (n=7), and normal breast tissues (n=5). Immunohistochemical reaction demonstrated that FasL was strongly expressed in breast cancer tissues (34/40) while only one fibroadenoma and one normal breast tissue reacted weakly positive for FasL. All fibroadenomas and normal breast tissues as well as the majority of breast cancer tissues expressed Fas on protein level. Quantitative RT-PCR analysis detected high expression of FasL mRNA in breast cancer tissues and fibroadenomas, whereas fibroadenomas showed the highest Fas mRNA copy numbers, followed by breast cancer tissues and normal breast tissues (P<0.05). Compared to FasL expression, TRAIL could be detected in less breast cancer tissues on protein level (21/40) and was found in only one fibroadenoma and none of the normal breast tissues. Thus, it can be concluded that malignant breast tumors show an altered expression of the two apoptosis-inducing ligands FasL and TRAIL. Accepted: 4 January 2000     

Chromosome changes and human malignant tumors

The data from home and foreign literature on chromosome changes in human tumours of different genesis and localization are analyzed. The role and significance of changes in the chromosome structure in malignant cells are discussed.     

Superoxide dismutases in malignant cells and human tumors

Reactive oxygen metabolites have multifactorial effects on the regulation of cell growth and the capacity of malignant cells to invade. Overexpression of the superoxide dismutases (SODs) in vitro increases cell differentiation, decreases cell growth and proliferation, and can reverse a malignant phenotype to a nonmalignant one. The situation in vivo is more complex due to multiple interactions of tumor cells with their environment. Numerous in vivo studies show that the superoxide dismutases can be highly expressed in aggressive human solid tumors. Furthermore, high SOD has occasionally been associated with a poor prognosis and with resistance to cytotoxic drugs and radiation. Most of the apparent conflicts between the above in vitro and in vivo observations can be reconciled by considering the net redox status of tumor cells in different environments. Administering high concentrations of SOD to cells in vitro is usually associated with a non- or less malignant phenotype, whereas secondary induction of SOD in tumors in vivo can be associated with an aggressive malignant transformation probably due to the altered (oxidative) redox state in the malignant cells. This concept suggests that for many types of tumors antioxidants could be used to diminish the invasive capability of malignant cells.     

Defining bad stroma in human breast tumors

Comment on: Witkiewicz AK, et al. Cell Cycle 2011; 10:1794-809.     

Differences in sexual functioning between patients with benign and malignant breast tumors

The aim of this study was to compare differences in sexual behavior between patients with benign and malignant breast tumors. A total of 187 patients treated for breast tumors (benign or malignant) at the General Hospital >Pozega<, Croatia, filled in the questionnaire between January 2001 and May 2003. Patients were asked to fill in the questionnaire one to ten years after treatment of breast tumor, while they were on their regular control visit. Deterioration in sexual life experienced 36.27% of patients with benign tumors and 51.76% of patients with malignant tumor (p<0.01). The main reason of sex life impairment in both groups was distortion of body image perception. Most of partners did not change their behavior toward women with breast tumors (48.72% for benign group and 41.82% or malignant group, p>0.05). A great amount of women in both groups felt certain change in her >body image<, but in greater extent in malignant group (41.18% vs. 25.49%), (p<0.05). From our results we can see that patients in this study do not recognize need for consultation with their physician regarding sex life after treatment of tumor (41.18% for benign and 35.29% in malignant group). It can be concluded that considerable amount of attention should be given to psychological aspects of recovery which can improve prognosis and quality of life in general.     

The diagnostic value of RNA oncomarkers in evaluation of malignant breast tumors

The levels of the RNA oncomarkers, telomerase (hTERT), cytokeratin-19 (CK-19), and mammaglobin (MAM) have been investigated in capillary blood of female patients with mammary ductal carcinoma. The study revealed overexpression of all three factors in patients with this pathology. This overexpression was not found in healthy donors and female patients with mammary fibroadenoma. Levels of the RNA oncomarkers return to the normal level within 10 days after successful tumor resection. These results have been used for the development of diagnostic kits, which may be applicable for differential diagnostics, screening and postoperation monitoring of patients with malignant breast tumors.     

Type B monoamine oxidase activity in human brain malignant tumors

An increase of monoamine oxidase (MAO) activity was observed in Central Nervous System (CNS) malignant tumors, but the isoform responsible was not identify (Marcozzi et al., 1985). In the present work we report additional data in order to ascertain whether the type A or B MAO isoform is increased in some malignant human tumors of CNS. In the homogenated tissues the amine oxidase activity was determined by the chemiluminescent method, using different and specific substrates or inhibitors of MAO A and B and copper-dependent enzymes. 19 samples from 4 different types of tumors and relative peritumoral tissues were analysed. The highest activity of was imputable to type B MAO.