Upregulation of COX-2 in MCF7 Breast Cancer Cells When Exposed to Shear Stress

Abstract

Background: Invasive breast cancer affects 1 in 8 women in the United States and causes one of the highest cancer mortality rates for women. Cyclooxygenase-2 (COX-2), a central enzyme in prostaglandin biosynthesis, is implicated in breast cancer initiation, progression, invasion, and metastasis, and has been linked to the mechanotransduction of breast cancers. However, it is not currently known if shear stress mediated mechanotransduction is affected by COX-2. Therefore, in this report, we hypothesized that COX-2 modulates shear stress mechanotransduction in luminal A breast cancer cell line MCF7, causing proliferation of tumor cells and chemoresistance. Methods: In order to probe this hypothesis, we utilized a bioreactor capable of stimulating tumor cells with variable shear stress in a 3D microenvironment and investigated the influence of shear stress stimulus on MCF7 breast cancer cells. Tumor cells were encapsulated within a hydrogel composed of agarose and collagen type I and placed under

Dynamic Heterochromatin States in Anisotropic Nuclei of Cells on Aligned Nanofibers

“…Around 10 000 MCF7 cells were seeded on the coverslip and cultured for 24 h before 4% paraformaldehyde (PFA) fixation or overnight DNA plasmid transfection with Lipofectamine 3000 according to manufacturer’s instructions. Cells were not found to be clustered, and isolated MCF7 cells are typically rounded in 2D and 3D environment …”

“…Cells were not found to be clustered, and isolated MCF7 cells are typically rounded in 2D and 3D environment. 66 For cell attachment on nanofibers, the scaffolds were placed in 1.5H glass-bottom 35 mm dishes and sterilized in 70% ethanol for 10 min. After three rounds of PBS washes, 500 μL of 2 μg/mL fibronectin was placed on the scaffolds and incubated at 37 °C for 2 h. MCF7 cells were seeded on the scaffolds by placing 100 μL droplets with a cell density of ∼33 000 cells/mL for 3 h, and then 2 mL of cell culture medium was added.…”