Identification of Potential Breast Cancer Stem Cell Biomarkers in the Secretome Using a Network Interaction Approach Analysis.

BACKGROUND: Breast cancer stem cells (BCSCs) play a role in the high rates of resistance, recurrence, and metastasis. The precise biomarkers of BCSCs can assist effectively in identifying cancer, assessing prognosis, diagnosing, and monitoring therapy. The aim of this study was to give a complete analysis for predicting specific biomarkers of BCSCs. METHODS: We aggregated profile datasets in this work to shed light on the underlying critical genes and pathways of BCSCs. We obtained two expression profiling by array datasets (GSE7513 and GSE7515) from the Gene Expression Omnibus (GEO) database to identify biomarkers in BCSCs. Enrichr was used to do functional analysis, including gene ontology (GO) and reactome pathway. Furthermore, the protein-protein interaction (PPI) of these differential expression genes (DEGs) was visualized using Cytoscape with the search tool for the retrieval of interacting genes (STRING). The hub genes in the PPI network were chosen for further investigation. RESULTS: We identified 65 up-regulated and 190 down- regulated DEGs and the GO enrichment analysis revealed that these DEGs were enriched in biological process related to tumorigenesis and stemness, including alter the extracellular matrix's physicochemical properties, cytoskeletal reorganisation, adhesion, motility, migration, growth, and survival. The Reactome analysis indicated that these DEGs were also involved in modulating function of ECM, regulation cancer metabolism and angiogenesis, tumor growth, proliferation, and metastasis. CONCLUSION: Our bioinformatic study revealed that FYN, INADL, OCLN, F11R, and TOP2A were potential biomarker panel of BCSCs from secretome.

Low activity of manganese superoxide dismutase (MnSOD) in blood of lung cancer patients with smoking history: relationship to oxidative stress.

Lung cancer is the primary cause of cancer death in the world. Although it is well established that tobacco smoke causes lung cancer, not all smokers develop lung cancer. Manganese superoxide dismutase (MnSOD), a major determinant of antioxidants in matrix mitochondria, plays a pivotal role in eliminating anion superoxide free radical generated from the tobacco smoke. The aim of this study was to analyze the enzyme activity of MnSOD in blood of lung cancer patients with a smoking history in relationship to oxidative stress. Samples were taken from leukocyte cells of 20 lung cancer patients in Persahabatan Hospital Jakarta. Control groups included 50 healthy smokers and 50 non smokers, all aged over 40 years. The MnSOD activity determined biochemically based on the inhibition of xanthin oxidase, of lung cancer patients was lower than the control group's (p<0.001). Plasma MDA levels, determined by reaction with thiobarbituric acid (TBA), were not significantly different (p=0.479), whereas plasma carbonyl levels were elevated (p=0.003). Free radical production in lung cancer patients thus appeared high. Smoker controls also tended to exhibit lower MnSOD and higher carbonyl radicals than their non-smoking counterparts. Continue cigarette smoke exposure may increase production of ROS and bring about a reduction of MnSOD, which could play a role in lung cancer development.