ELECTROCHEMICAL STUDY OF THE CD(II)/CD(HG) SYSTEM IN 2-MERCAPTOACETIC ACID-SOLUTIONS
Authors: TURYAN, I; MANDLER, D
A detailed study of the Cd(II)/Cd(Hg) system in 2-mercaptoacetic acid, H(2)MA, solutions has been carried out in 1 M NaClO4 at pH 4.8-12.0. The electrochemical behavior of 2-mercaptoacetic acid at a dropping mercury electrode was studied as well. Since all complexes that are formed in the solution undergo a reversible two-electron reduction, mathematical analysis of the data, provided the composition of the various complexes. Thus, the stability constants of the following complexes: Cd(SCH2CO2)(3)(4-), Cd(SCH2CO2)(2)(2-), Cd(SCH2CO2), CdH(SCH2CO2)(3)(3-), CdH2(SCH2CO2)(3)(2-), CdH(SCH2CO2)(2)(-), CdH2(SCH2CO2)(2) and CdH(SCH2CO2)(+) were determined and their degree of formation as a function of pH were estimated. In addition, the protonation constants of the ligand were calculated. The present results indicate that H(2)MA forms extremely stable bidentate complexes with cadmium ions. The formation of the various complexes as a Function of pH reveals that at pH 10.7-12.0 the complex Cd(SCH2CO2)(3)(4-) predominates, whereas at pH 4.8-6.0 the complexes CdH2(SCH2CO2)(2) and CdH(SCH2CO2)(+) are dominant. At pH 6.1-10.6 different protonated and unprotonated complexes composed of one to three ligands, coexist.
COMP Gene Coexpresses With EMT Genes and Is Associated With Poor Survival in Colon Cancer Patients
JOURNAL OF SURGICAL RESEARCH
Authors: Nfonsam, Valentine N.; Nfonsam, Landry E.; Chen, Debbie; Omesiete, Pamela N.; Cruz, Alejandro; Runyan, Raymond B.; Jandova, Jana
Background: About 1.2 million new cases of colon cancer (CC) and 0.6 million deaths are reported every year, establishing CC as an important contributor to worldwide cancer morbidity and mortality. Although the overall incidence and mortality of CC have declined over the past 3 decades, the number of early-onset colon cancer ([EOCC], patients <50 y old) continues to rise alarmingly. These young patients are often diagnosed at a more advanced stage and tend to have poor survival. Our recently published data showed that the cartilage oligomeric matrix protein (COMP) is overexpressed in early-onset colon cancer patients. COMP is also reported in several cancers to coexpress with epithelial-mesenchymal transition (EMT) transcription factors. Given the role of EMT in cancer metastasis and cell invasion, we assessed the correlation between COMP gene expression and EMT gene expression in CC, and COMP's relationship to patient survival. Methods: mRNA expression of COMP was compared to that of EMT markers using the UCSC Cancer Genomics Browser. Survival analysis was performed using the UCSC Xena Browser for cancer genomics. Results: Expression analysis revealed coexpression of COMP with the EMT markers CDH2, FN1, VIM, TWIST1, TWIST2, SNAI1, SNAI2, ZEB1, ZEB2, POSTN, MMP2, MMP9, and COL1A1. Samples that were more mesenchymal had higher expression levels of COMP and EMT markers, thus suggesting a potential role of COMP in EMT. Patients with increased COMP expression presented with poorer overall survival compared to patients with no change or reduced COMP expression (P = 0.02). Conclusions: These findings reveal COMP as a potential biomarker for CC especially in more aggressive CC and CC in young patients, with a likely role in EMT during tumor metastasis and invasion, and a contributing factor to patient survival. Published by Elsevier Inc.