MATERIALS AND METHODS: The STIM1 effect was assessed via dicersubstrate siRNA-mediated STIM1 knockdown. The effect of STIM1 knockdown on the expression of AKT and MAPK pathway-related genes and reactive oxygen species (ROS) generation-related genes was tested using real-time polymerase chain reaction. Cellular functions, including ROS generation, cell proliferation, and colony formation, were also evaluated following STIM1 knockdown.
RESULTS: The findings revealed that STIM1 knockdown reduced intracellular ROS levels via downregulation of NOX2 and PKC. These findings were associated with the downregulation of AKT, KRAS, MAPK, and CMYC. BCL2 was also downregulated, while BAX was upregulated following STIM1 knockdown. Furthermore, STIM1 knockdown reduced THP-1 cell proliferation and colony formation.
CONCLUSION: This study has demonstrated the role of STIM1 in promoting AML cell proliferation and survival through enhanced ROS generation and regulation of AKT/MAPK-related pathways. These findings may help establish STIM1 as a potential therapeutic target for AML treatment.
METHODS: Blood samples were collected from 75 TNBC patients and 83 controls. Genomic DNA was extracted from blood samples and the SNP genotyping was performed by using PCR-RFLP technique. The genotypes were characterized and grouped into homozygous wildtype, heterozygote and homozygous variant based on the band size. The result was subjected to statistical analysis.
RESULTS: The A allele and AA genotype of ABCG2 421 C>A had OR of 3.011 (p=0.003, 95% CI: 1.417-6.398) and 9.042 (p=0.011, 95% CI: 1.640-49.837), to develop advanced staging carcinoma respectively. The AA genotype of ABCG2 421 C>A polymorphism was also associated with metaplastic and medullary carcinoma with an OR of 6.429 (p=0.018, 95% CI: 1.373-30.109). A significant association was also found in haplotype 34G/421A of ABCG2 with advanced cancer staging as well as metaplastic and medullary carcinoma with OR of 2.347 (p=0.032, 95% CI: 1.010-5.560) and 2.546 (p=0.008, 95% CI: 1.005-6.447), respectively. Conclusion: The present study suggests that ABCG2 421 C>A polymorphism was associated with metaplastic and medullary histology and advanced cancer staging in TNBC patients.
METHODS: In total, 80 samples of tumor and matched adjacent normal tissues were collected from breast cancer patients at Seberang Jaya Hospital (SJH) and Kepala Batas Hospital (KBH), both in Penang, Malaysia. The protein expression profiles of breast cancer and normal tissues were mapped by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The Gel-Eluted Liquid Fractionation Entrapment Electrophoresis (GELFREE) Technology System was used for the separation and fractionation of extracted proteins, which also were analyzed to maximize protein detection. The protein fractions were then analyzed by tandem mass spectrometry (LC-MS/MS) analysis using LC/MS LTQ-Orbitrap Fusion and Elite. This study identified the proteins contained within the tissue samples using de novo sequencing and database matching via PEAKS software. We performed two different pathway analyses, DAVID and STRING, in the sets of proteins from stage 2 and stage 3 breast cancer samples. The lists of molecules were generated by the REACTOME-FI plugin, part of the CYTOSCAPE tool, and linker nodes were added in order to generate a connected network. Then, pathway enrichment was obtained, and a graphical model was created to depict the participation of the input proteins as well as the linker nodes.
RESULTS: This study identified 12 proteins that were detected in stage 2 tumor tissues, and 17 proteins that were detected in stage 3 tumor tissues, related to their normal counterparts. It also identified some proteins that were present in stage 2 but not stage 3 and vice versa. Based on these results, this study clarified unique proteins pathways involved in carcinogenesis within stage 2 and stage 3 breast cancers.
CONCLUSIONS: This study provided some useful insights about the proteins associated with breast cancer carcinogenesis and could establish an important foundation for future cancer-related discoveries using differential proteomics profiling. Beyond protein identification, this study considered the interaction, function, network, signaling pathway, and protein pathway involved in each profile. These results suggest that knowledge of protein expression, especially in stage 2 and stage 3 breast cancer, can provide important clues that may enable the discovery of novel biomarkers in carcinogenesis.