KLF4 and chondrosarcoma: We established a KLF4 reporter cell line from SW1353 human chondrosarcoma cells, which enabled detection of endogenous KLF4 activation by HiBiT luminescence (Supplemental Figure 1; supplemental material available online with this article; https://doi.org/10.1172/jci.insight.170513DS1; also see Methods for details).