PTGFRN and glioblastoma: When comparing metastatic cancer cells to their non‐metastatic counterparts, PTGFRN mRNA and protein expression have been reported to be significantly upregulated in some lung cancers (NCI‐H460), melanomas (MDA‐MB‐435), and glioblastomas (U87MG and A172) [18, 19, 20, 21].