MATERIALS AND METHODS: ER+ MCF7 and ER- MDA-MB-231 cell lines were subjected to two-dimensional electrophoresis (2-DE) and spots of interest were identified by matrix-assisted laser desorption/ionization time of- flight/time- of-flight (MALDI-TOF/TOF) mass spectrometry (MS) analysis after downregulation of RhoGDIα using short interfering RNA (siRNA) and upregulated using GFP-tagged ORF clone of RhoGDIα.
RESULTS: The results showed a total of 35 proteins that were either up- or down-regulated in these cells. Here we identifed 9 and 15 proteins differentially expressed with silencing of RhoGDIα in MCF-7 and the MDA-MB-231 cells, respectively. In addition, 10 proteins were differentially expressed in the upregulation of RhoGDIα in MCF7, while only one protein was identified in the upregulation of RhoGDIα in MDA-MB-231. Based on the biological functions of these proteins, the results revealed that proteins involved in cell migration are more strongly altered with RhoGDI-α activity. Although several of these proteins have been previously indicated in tumorigenesis and invasiveness of breast cancer cells, some ohave not been previously reported to be involved in breast cancer migration. Hence, these proteins may serve as useful candidate biomarkers for tumorigenesis and invasiveness of breast cancer cells.
CONCLUSIONS: Future studies are needed to determine the mechanisms by which these proteins regulate cell migration. The combination of RhoGDIα with other potential biomarkers may be a more promising approach in the inhibition of breast cancer cell migration.
Objectives: A cross-sectional study was carried out to explore the association of occupational, socio-demographic, and lifestyle factors with lung functions in traffic policemen in Kuala Lumpur (KL) and Johor Bahru (JB).
Methods: A spirometer was used to measure lung function of subjects, whereas a self-administered questionnaire was used to obtain their information on background data, lifestyle, and occupational factors. The statistical test used was Spearman rho's test and chi-square test; then, the factors were further tested using Logistic regressions.
Findings: 134 male subjects were selected as respondents in this study with 83% response rate. Among all the factors tested, age (FVC: χ = 8.42(3), p = 0.04), (FEV: χ = 8.26(3), p = 0.04), rank (FVC: χ = 8.52(3), p = 0.04), (FEV: χ = 8.05(3), p = 0.04), duration of services (FVC: χ = 11.0(1), p = 0.04), (FEV: χ = 6.53(1), p = 0.01), and average working hours (with the Measured FVC (litre), r = -3.97, p < 0.001; Measured FEV1 (litre), r = -3.70, p < 0.001; Predicted FVC, r = -0.49, p < 0.001; Predicted FEV1, r = -0.47, p < 0.001; and %Ratio FEV1/FV, r = -0.47, p < 0.001) were significantly related to lung function among traffic police.
Conclusions: Occupational factors play a crucial role, and hence, the authorities should take action in generating flexible working hours and the duration of services accordingly. The data from this study can help by serving as a reference to the top management of traffic police officers to develop occupational safety and health guideline for police officers to comply with the Occupational Safety and Health Act (OSHA, Act 514 1994).