ELISA was conducted to check the concentrations of proteins involved in multiple intracellular signaling pathways, responsible for the promotion of tumor growth and breast cancer progression, namely matrix metalloproteinase (MMP)‑2, matrix MMP‑9, tumor necrosis factor‑α (TNF‑α), cyclooxygenase‑2 (COX‑2), soluble intercellular adhesion molecule 1 (sICAM1) and mTOR.
Women were classified as regular or non-regular users of aspirin, COX-2 inhibitors, ibuprofen and other NSAIDs, and acetaminophen (control) based on self-report at follow-up of ever using the medication for at least twice a week for ≥1 month prior to breast cancer diagnosis.
Activation of HIF-1<i>α</i> by <i>δ</i>-Opioid Receptors Induces COX-2 Expression in Breast Cancer Cells and Leads to Paracrine Activation of Vascular Endothelial Cells.
In mtSNP-subset analysis, the gene MT-CO2 (P = 0.001, q = 0.09) in Complex IV (cytochrome c oxidase) and MT-ND2 (P = 0.004, q = 0.19) in Complex I (NADH dehydrogenase (ubiquinone)) were significantly associated with breast cancer risk.
All results demonstrated that HPPDC nanoparticles can efficiently overcome drug resistance in breast cancer both in vitro and in vivo by combining chemotherapy and COX-2 inhibitor.
Interestingly, two mitochondrial inner membrane proteins MT-CO2 (encoded by the mitochondrial genome) and COX6c (encoded by the nuclear genome) were highly prevalent in the plasma of melanoma patients, as well as in ovarian and breast cancer patients.
This work demonstrated the potential anti-cancer effects of Andro, indicating that Andro could inhibit COX-2 expression through attenuating p300 HAT activity and suppress angiogenesis via VEGF pathway, and thereby could be developed as an antitumor agent for the treatment of breast cancer.
Tumor-promoting genes correlated with the expression of COX1, COX2, and ALOX5 are known to effectively increase mitogenesis, mutagenesis, angiogenesis, cell survival, immunosuppression and metastasis in the pathogenesis of breast cancer.
All these experiments suggest that ME inhibits breast cancer cell proliferation and apoptosis by inhibiting the expression of COX-2 in MCF-7 and MDAMB- 468 cells.
Analysis of clinical samples demonstrated that COX-2/PGE<sub>2</sub> /EP<sub>4</sub> signaling is elevated in basal-like and chemoresistant breast carcinoma and is correlated with survival and relapse of breast cancer.
Our findings suggest that concurrent use of glucocorticoids, ACE inhibitors, aspirin, NSAIDs, selective COX-2 inhibitors, digoxin, and opioids has little impact on breast cancer recurrence.
Further study suggested that AKT1 and cyclooxygenase-2 (COX2; PTGS2) might mediate the CXCR2 signaling to inversely control the breast cancer metastasis and chemoresistance through the regulation of EMT, apoptosis, and senescence.
Knockdown delta-5-desaturase in breast cancer cells that overexpress COX-2 results in inhibition of growth, migration and invasion via a dihomo-γ-linolenic acid peroxidation dependent mechanism.
However, the functional aspects of EP3 receptor in breast cancer and the way how EP3 may oppose the pro-tumorigenic effects of PGE2 elevation and COX-2 overexpression are not fully understood so far.