Clinical usefulness of alterations in sialic acid, sialyl transferase and sialoproteins in breast cancer.

Biochemistry Research Division, The Gujarat Cancer & Research Institute, Asarwa, 380 016 Ahmedabad, India.
Indian Journal of Clinical Biochemistry 07/2004; 19(2):60-71. DOI: 10.1007/BF02894259
Source: PubMed

ABSTRACT Sialic acid, the end moieties of the carbohydrate chains are biologically important and essential for functions of glycoconjugates and are reported to be altered in cancer patients. Two hundred and twenty five breast cancer (BC) patients, 100 patients with benign breast disease (BBD) and 100 healthy females (controls) were enrolled for the study. Eight hundred and twenty four follow-up samples of 225 breast carcinoma patients were also evaluated. The association of sialic acid forms, sialyltransferase and α-2-6 sialoproteins levels with presence and extent as well as prognosis of breast carcinoma was studied. Serum sialic acid forms and sialyltransferase revealed significantly elevated levels among untreated breast cancer patients as compared to the controls, patients with BBD as well as cancer patients in remission. Non-responders showed comparable levels of the markers with those found in breast cancer patients at the time of diagnosis. Higher levels of sialic acid forms at diagnosis were associated with poor prognosis. A positive correlation between serum levels of different forms of sialic acids and extent of malignant disease was observed. The changes in serum proteins with terminal α-2-6 sialic acid correlated well with alterations in the levels of sialic acid forms and sialyltransferase. Malignant tissues showed elevated levels of sialic acid and sialyltransferase as compared to surrounding normal tissues.The results suggested potential utility of these markers in evaluation of clinical outcome.


Available from: Rachana Sainger, May 12, 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: We aimed to investigate of protective role of proanthocyanidin (PA) and vitamin E (vit E) against to toxic effect of formaldehyde (FA). Twenty-eight Wistar albino rats were divided into four groups: control group, rats treated with FA intraperitoneal (i.p.) (10 mg/kg), FA + vit E intragastric (i.g.) (30 mg/kg), and FA + PA i.g. (100 mg/kg). We assayed superoxide dismutase (SOD), glutathione peroxidase (Gpx), myeloperoxidase (MPO) activity and levels of malondialdehyde (MDA) and total sialic acid (TSA) in liver. Liver tissue was taken in order to morphological analysis and hepatocytes apoptosis using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay immunostaining. SOD decreased in FA and increased in FA + vit E and FA + PA (p < 0.05). Gpx didn't change in FA and increased in FA + PA (p < 0.05). No significant variation between the groups was found in MPO activity. MDA increased only in FA and decreased in FA + vit E and FA+PA (p < 0.05). TSA didn't alter in FA and FA + vit E but decreased in FA + PA (p < 0.05). Degeneration in hepatocytes and endothelial cells, cytoplasm losses, vacuolization, picnotic nuclei, and mononuclear cell infiltration were identified in FA. Degeneration in chromatin material, membrane damage in mitochondria and losses in mitochondrial cristae in hepatocytes were observed in FA. We found that partially recovery in liver as a result of FA + vit E and FA + PA. We have concluded that long term use should be investigated for complete explanation of PA's protective effects on FA toxicity. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014.
    Environmental Toxicology 06/2014; DOI:10.1002/tox.22010 · 2.56 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Aberrant glycosylation is the universal feature of cancer and components of various glycoconjugates, such as sialic acid is found to rise in various malignancies. The objective of this study was to evaluate the serum and salivary sialic acid in oral potentially malignant disorders (OPMD) and oral cancer (OC) to investigate the possibility of using this as a diagnostic marker. Materials and Methods: The study included 85 subjects, who were grouped as control (30), OPMD patients (25), and oral cancer patients (30). Serum and unstimulated whole saliva was collected from subjects of all groups and sialic acid estimation was done using spectrophotometry. The results were tabulated and analyzed statistically. Results: The mean serum sialic acid levels in normal, OPMD, and oral cancer group were 7.515, 19.620, and 55.235 mg/dL, respectively, whereas the levels of salivary sialic acid were 1.5113, 2.3302, and 9.0304 mg/dL, respectively. A very highly significant rise (P < 0.005) in serum and salivary sialic acid was observed in the study subjects compared with that of the control. Conclusions: The present study showed a significant and gradual increase in serum and salivary sialic acid from control to oral potentially malignant disorders to oral cancer. From this study we can suggest that sialic acid can be used as a reliable biomarker. As this monosaccharide is observed in saliva in detectable quantity, saliva can be used as a diagnostic medium for screening and early detection of oral cancer.
    Indian Journal of Cancer 07/2014; 51(3):214-218. DOI:10.4103/0019-509X.146720 · 1.13 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We investigated possible effects of proanthocyanidin (PA) and vitamin E on damage to rat kidneys induced by formaldehyde (FA), using biochemical characteristics and light and electron microscopy. Male rats were divided into control, FA, PA and vitamin E treated groups. Kidney tissue was observed by light and electron microscopy. Bcl-2/Bax rate was measured using immunohistochemistry. Malondialdehyde (MDA) and total sialic acid (TSA) levels, superoxide dismutase (SOD), glutathione peroxidase (Gpx), catalase (CAT) and myeloperoxidase (MPO) activities were measured. We found that FA caused damage to the parietal epithelial layer of the glomerulus, mononuclear cell infiltration, membrane damage in renal tubules, pyknotic nuclei, hypertrophic cells in Henle's loop and tubules, and loss of renal tubule integrity. We also observed invagination of the nuclear membrane, irregularity of chromatin material and loss of mitochondrial cristae. We observed increased Bcl-2 and Bax immunostaining in the FA group, but the Bcl-2/Bax rate remained unchanged in FA, PA and vitamin E groups compared to controls. Tissue MDA and TSA levels, and CAT and Gpx activities were increased, and SOD and MPO activities were decreased by FA toxicity. We observed a protective effect of PA in tissue MDA and TSA levels and SOD activities, because there was no difference in the PA group compared to the control group. We investigated the antioxidant effects of PA and vitamin E and found protective effects of PA against apoptosis.
    Biotechnic and Histochemistry 09/2014; DOI:10.3109/10520295.2014.954620 · 1.00 Impact Factor