Overcoming TRAIL-resistance by sensitizing prostate cancer 3D spheroids with taxanes

Abstract

Three-dimensional spheroid cultures have been shown to better physiologically mimic the cell-cell and cell-matrix interactions that occur in solid tumors more than traditional 2D cell cultures. One challenge in spheroid production is forming and maintaining spheroids of uniform size. Here, we developed uniform, high-throughput, multicellular spheroids that self-assemble using microwell plates. DU145 and PC3 cells were cultured as 2D monolayers and 3D spheroids to compare sensitization of TRAIL-resistance cancer cells to TRAIL mediated apoptosis via chemotherapy based on dimensionality. Monocultured monolayers and spheroids were treated with soluble TRAIL alone (24 hr), DTX or CBZ alone (24 hr), or a combination of taxane and TRAIL (24 + 24 hr) to determine the effectiveness of taxanes as TRAIL sensitizers. Upon treatment with soluble TRAIL or taxanes solely, monolayer cells and spheroids exhibited no significant reduction in cell viability compared to the control, indicating that both cell lines are resistant to TRAIL and taxane alone in 2D and 3D. Pretreatment with CBZ or DTX followed by TRAIL synergistically amplified apoptosis in 2D and 3D DU145 cell cultures. PC3 spheroids were more resistant to the combination therapy, displaying a more additive effect in the DTX + TRAIL group compared to 2D. There was a downregulation of DR4/5 expression in spheroid form compared to monolayers in each cell line. Additionally, normal fibroblasts (NFs) and cancer-associated fibroblasts (CAFs) were cocultured with both PCa cell lines as spheroids to determine if CAFs confer additional resistance to chemotherapy. We determined that co-cultured spheroids show similar drug resistance to monocultured spheroids when treated with taxane plus TRAIL treatment. Collectively, these findings suggest how the third dimension and cocultures of different cell types effect the sensitization of androgen-independent prostate cancer cells to TRAIL, suggesting therapeutic targets that could overcome TRAIL-resistance in metastatic castration-resistant prostate cancer (mCRPC).

Tuning of TRAIL clustering on the surface of nanoscale liposomes by phase separation

“…We used human prostate cancer PC3 and DU145 cells (both purchased from American Type Culture Collection) which exhibit high and medium sensitivity to TRAIL, respectively, to compare the apoptotic activity of the phase-separated liposomes conjugated with different numbers of TRAIL molecules. 24 Our previous studies found that each of these two cell lines expresses both DR4 and DR5, with a higher expression of DR5 than DR4. 25 In both of the cell lines, the TRAIL liposomes showed higher cytotoxic effects than free TRAIL after 24 h of treatment.…”

Spatial distribution of tumor-associated macrophages in an orthotopic prostate cancer mouse model

“…In contrast to our 2016 orthotopic prostate tumor study, TRAIL liposomes were unable to reduce primary tumor volume [ 35 ]. Recent data suggests DU145 cells are TRAIL resistant and show very minimal apoptosis in 2D and 3D cultures when treated with TRAIL alone [ 57 , 58 ]. Tumor cells can also develop mechanisms to avoid TRAIL cytotoxicity [ 55 ].…”

“…Future studies should investigate dosing with different concentrations of TRAIL liposomes to establish a dose response and maximum tolerated dose in mice. If necessary, EST liposomes can be combined with known TRAIL sensitizers such as taxanes [ 57 , 58 ] curcumin [ 59 ], piperlongamine [ 60 ], or Yoda1 [ 61 , 62 ].…”

Chemical Activation and Mechanical Sensitization of Piezo1 Enhance TRAIL-Mediated Apoptosis in Glioblastoma Cells

“…One way in which TRAIL can become sensitized is through the fluid shear stress (FSS) that CTCs experience in the circulation . Alternatively, under static conditions, TRAIL resistance can be overcome with molecular therapeutics using molecules such as aspirin, taxanes, and piperlongumine. − Previous studies have found that the activation of the mechanosensitive ion channel Piezo1 via the agonist Yoda1 also induces TRAIL sensitization under static conditions and have characterized the toxicity of this treatment using HUVEC cells as a non-cancerous control. , The mechanism by which the small-molecule Yoda1 activates Piezo1, a mechanosensitive Ca 2+ ion channel, is currently unknown. − However, Ca 2+ influx through Piezo1 is known to lead to a number of cellular responses, including apoptosis . In vivo, Yoda1 was found to cause a significant increase in apoptosis in prostate cancer, breast cancer, and colon cancer cell lines compared to TRAIL alone …”