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Breast cancer is one of the major issues in the field of oncology, reported with a higher prevalence rate in women worldwide. In attempt to reveal the potential biomarkers for breast cancer, the findings of differentially glycosylated haptoglobin and osteonectin in previous study have drawn our attention towards glycoproteins of secretome from the MCF-7 cancer cell line. In the present study, further analyses were performed on the medium of MCF-7 cells by subjecting it to two-dimensional analyses followed by image analysis in contrast to the medium of human mammary epithelial cells (HMEpC) as a negative control. Carboxypeptidase A4 (CPA4), alpha-1-antitrypsin (AAT), haptoglobin (HP), and HSC70 were detected in the medium of MCF-7, while only CPA4 and osteonectin (ON) were detected in HMEpC medium. In addition, CPA4 was detected as upregulated in the MCF-7 medium. Further analysis by lectin showed that CPA4, AAT, HP, and HSC70 were secreted as N-glycan in the medium of MCF-7, with HP also showing differentially N-glycosylated isoforms. For the HMEpC, only CPA4 was detected as N-glycan. No O-glycan was detected in the medium of HMEpC but MCF-7 expressed O-glycosylated CPA4 and HSC70. All these revealed that glycoproteins could be used as glycan-based biomarkers for the prognosis of breast cancer. [ABSTRACT FROM AUTHOR]

Galactose-binding and mannose-binding lectins from the champedak fruit, which is native to South-east Asia, exhibit useful potential clinical applications. The specificity of the two lectins for their respective ligands allows the detection of potential cancer biomarkers and monitoring of the glycosylated state of proteins in human serum and/or urine. To fully understand and expand the use of these natural proteins, their complete sequences and crystal structures are presented here, together with details of sugar binding. [ABSTRACT FROM AUTHOR]

Background Altered levels of specific matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in the aqueous humour of primary open-angle glaucoma (POAG) eyes have been described. In this study, levels of specific MMPs and TIMPs in the aqueous humour of primary angle-closure glaucoma (PACG) eyes were measured and compared with those of POAG as well as non-glaucoma control eyes. Methods Aqueous humour from 16 PACG, 28 POAG and 27 control eyes were sampled during intraocular surgery. Levels of total protein, MMP-2, MMP-3, TIMP-1 and TIMP-2 were quantified by protein assay and enzyme immunoassay. Results Total protein levels were significantly higher in PACG (0.426 ± 0.126 mg/ml, p = 0.043) and POAG (0.578 ± 0.360 mg/ml, p = 0.007) compared to controls (0.292 ± 0.192 mg/ml). The difference between PACG and POAG was not significant (p = 0.158). MMP-2 was significantly higher in PACG (p = 0.032) and POAG (p < 0.001) compared to controls. The difference between PACG and POAG was also not significant (p = 0.133). MMP-3 was significantly higher in POAG compared to controls (p = 0.002) and PACG (p = 0.029). The difference between PACG and controls was not significant (p = 0.962). TIMP-1 was significantly higher in PACG (p = 0.049) and POAG (p = 0.010) compared to controls. The difference between PACG and POAG was also not significant (p = 0.961). TIMP-2 was significantly higher in POAG (p = 0.004) compared to controls. The difference between PACG and either controls or POAG was not significant (p > 0.05). Although not statistically significant (p > 0.05), the MMP-2/TIMP-2 ratio was highest in PACG (2.83 ± 7.40), followed by POAG (1.38 ± 1.55) and controls (1.34 ± 3.05). Similarly, the MMP-2/TIMP-1 ratio was highest in PACG (1.50 ± 1.69), followed by POAG (1.40 ± 0.77) and controls (1.15 ± 0.92). The MMP-2 + MMP-3/TIMP-1 + TIMP-2 ratio was higher in PACG (0.83 ± 0.80) and POAG (0.82 ± 0.53) compared to controls (0.70 ± 0.63). In both POAG and PACG, there were no significant differences in the levels of total protein, MMP-2, MMP-3, TIMP-1 and TIMP-2 between patients on prostaglandin analogues and those not. Conclusion We found altered levels of MMPs and TIMPs as well as imbalance of MMP:TIMP ratios in the aqueous humour of PACG eyes that were different from POAG and non-glaucoma control eyes. [ABSTRACT FROM AUTHOR]

The fruit pulp extract of Tamarindus indica has been reported for its antioxidant and hypolipidemic properties. In this study, the methanol extract of T. indica fruit pulp was investigated for its effects on the abundance of HepG2 cell lysate proteins. Cell lysate was extracted from HepG2 cells grown in the absence and presence of the methanol extract of T. indica fruit pulp. Approximately 2500 spots were resolved using two-dimensional gel electrophoresis and the abundance of 20 cellular proteins was found to be significantly reduced. Among the proteins of reduced abundance, fourteen, including six proteins involved in metabolism (including ethanolamine phosphate cytidylyltransferase), four mitochondrial proteins (including prohibitin and respiratory chain proteins), and four proteins involved in translation and splicing, were positively identified by mass spectrometry and database search. The identified HepG2 altered abundance proteins, when taken together and analyzed by Ingenuity Pathways Analysis (IPA) software, are suggestive of the effects of T. indica fruit pulp extract on metabolism and inflammation, which are modulated by LXR/RXR. In conclusion, the methanol fruit pulp extract of T. indica was shown to cause reduced abundance of HepG2 mitochondrial, metabolic, and regulatory proteins involved in oxidative phosphorylation, protein synthesis, and cellular metabolism. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the salivary proteins that are associated with periodontitis in patients with Type 2 diabetes mellitus (T2DM). Volunteers for the study were patients from the Diabetic Unit, University of Malaya Medical Centre, whose periodontal status was determined. The diabetic volunteers were divided into two groups, i.e., patients with periodontitis and those who were periodontally healthy. Saliva samples were collected and treated with 10% TCA/acetone/20 mM DTT to precipitate the proteins, which were then separated using two-dimensional polyacrylamide gel electrophoresis. Gel images were scanned using the GS-800TM Calibrated Densitometer. The protein spots were analyzed and expressed in percentage volumes. The percentage volume of each protein spot was subjected to Mann-Whitney statistical analysis using SPSS software and false discovery rate correction. When the expression of the salivary proteins was compared between the T2DM patients with periodontitis with those who were periodontally healthy, seven proteins, including polymeric immunoglobulin receptor, plastin-2, actin related protein 3, leukocyte elastase inhibitor, carbonic anhydrases 6, immunoglobulin J and interleukin-1 receptor antagonist, were found to be differentially expressed (p < 0.01304). This implies that the proteins may have the potential to be used as biomarkers for the prediction of T2DM patients who may be prone to periodontitis. [ABSTRACT FROM AUTHOR]

Background: Diagnosis of ovarian carcinoma is in urgent need for new complementary biomarkers for early stage detection. Proteins that are aberrantly excreted in the urine of cancer patients are excellent biomarker candidates for development of new noninvasive protocol for early diagnosis and screening purposes. In the present study, urine samples from patients with ovarian carcinoma were analysed by two-dimensional gel electrophoresis and the profiles generated were compared to those similarly obtained from age-matched cancer negative women. Results: Significant reduced levels of CD59, kininogen-1 and a 39 kDa fragment of inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4), and enhanced excretion of a 19 kDa fragment of albumin, were detected in the urine of patients with ovarian carcinoma compared to the control subjects. The different altered levels of the proteins were confirmed by Western blotting using antisera and a lectin that bind to the respective proteins. Conclusion: CD59, kininogen-1 and fragments of ITIH4 and albumin may be used as complementary biomarkers in the development of new noninvasive protocols for diagnosis and screening of ovarian carcinoma. [ABSTRACT FROM AUTHOR]

Background: The general enhanced expression of α1-antichymotrypsin (ACT), clusterin (CLU), α1-antitrypsin (AAT), haptoglobin β-chain (HAP), and leucine rich glycoprotein (LRG) in the sera of patients with epithelial ovarian carcinoma (EOCa) was recently reported. In the present study, we compared the expression of the serum acute-phase proteins (APPs) in the patients according to their stages of cancer. Results: Different altered stage correlative expression of the high abundance serum APPs was demonstrated in sera of the patients studied. While the expression of ACT, HAP and AAT appeared to demonstrate positive correlation with the three initial stages of the cancer, inverse correlation was apparently detected in the expression of LRG and CLU. For patients who were diagnosed with stage IV of the cancer, expression of the serum APPs did not conform to the altered progression changes. Conclusion: Our results highlight the potential prognostic significance of selective high abundance serum APPs in patients with EOCa. [ABSTRACT FROM AUTHOR]

Background: Altered levels of specific matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in the aqueous humour of primary open-angle glaucoma (POAG) eyes have been described. In this study, levels of specific MMPs and TIMPs in the aqueous humour of primary angle-closure glaucoma (PACG) eyes were measured and compared with those of POAG as well as non-glaucoma control eyes.Methods: Aqueous humour from 16 PACG, 28 POAG and 27 control eyes were sampled during intraocular surgery. Levels of total protein, MMP-2, MMP-3, TIMP-1 and TIMP-2 were quantified by protein assay and enzyme immunoassay.Results: Total protein levels were significantly higher in PACG (0.426 ± 0.126 mg/ml, p = 0.043) and POAG (0.578 ± 0.360 mg/ml, p = 0.007) compared to controls (0.292 ± 0.192 mg/ml). The difference between PACG and POAG was not significant (p = 0.158). MMP-2 was significantly higher in PACG (p = 0.032) and POAG (p < 0.001) compared to controls. The difference between PACG and POAG was also not significant (p = 0.133). MMP-3 was significantly higher in POAG compared to controls (p = 0.002) and PACG (p = 0.029). The difference between PACG and controls was not significant (p = 0.962). TIMP-1 was significantly higher in PACG (p = 0.049) and POAG (p = 0.010) compared to controls. The difference between PACG and POAG was also not significant (p = 0.961). TIMP-2 was significantly higher in POAG (p = 0.004) compared to controls. The difference between PACG and either controls or POAG was not significant (p > 0.05). Although not statistically significant (p > 0.05), the MMP-2/TIMP-2 ratio was highest in PACG (2.83 ± 7.40), followed by POAG (1.38 ± 1.55) and controls (1.34 ± 3.05). Similarly, the MMP-2/TIMP-1 ratio was highest in PACG (1.50 ± 1.69), followed by POAG (1.40 ± 0.77) and controls (1.15 ± 0.92). The MMP-2 + MMP-3/TIMP-1 + TIMP-2 ratio was higher in PACG (0.83 ± 0.80) and POAG (0.82 ± 0.53) compared to controls (0.70 ± 0.63). In both POAG and PACG, there were no significant differences in the levels of total protein, MMP-2, MMP-3, TIMP-1 and TIMP-2 between patients on prostaglandin analogues and those not.Conclusion: We found altered levels of MMPs and TIMPs as well as imbalance of MMP:TIMP ratios in the aqueous humour of PACG eyes that were different from POAG and non-glaucoma control eyes. [ABSTRACT FROM AUTHOR]

The fruit pulp extract of Tamarindus indica has been reported for its antioxidant and hypolipidemic properties. In this study, the methanol extract of T. indica fruit pulp was investigated for its effects on the abundance of HepG2 cell lysate proteins. Cell lysate was extracted from HepG2 cells grown in the absence and presence of the methanol extract of T. indica fruit pulp. Approximately 2500 spots were resolved using two-dimensional gel electrophoresis and the abundance of 20 cellular proteins was found to be significantly reduced. Among the proteins of reduced abundance, fourteen, including six proteins involved in metabolism (including ethanolamine phosphate cytidylyltransferase), four mitochondrial proteins (including prohibitin and respiratory chain proteins), and four proteins involved in translation and splicing, were positively identified by mass spectrometry and database search. The identified HepG2 altered abundance proteins, when taken together and analyzed by Ingenuity Pathways Analysis (IPA) software, are suggestive of the effects of T. indica fruit pulp extract on metabolism and inflammation, which are modulated by LXR/RXR. In conclusion, the methanol fruit pulp extract of T. indica was shown to cause reduced abundance of HepG2 mitochondrial, metabolic, and regulatory proteins involved in oxidative phosphorylation, protein synthesis, and cellular metabolism. [ABSTRACT FROM AUTHOR]