Panoply™ Human FLT1 Knockdown Stable Cell Line

Studies have shown that abnormal expression of Fms-related tyrosine kinase 1 (Flt1) is associated with various malignant tumors, but its role in the pathology of glioblastoma remains to be elucidated. Here, researchers constructed glioblastoma cell lines with sustained silencing or overexpression of Flt1 to investigate the role of Flt1 in regulating glioblastoma cell proliferation, migration, and invasion. They found that ectopic expression of Flt1 promoted glioblastoma cell migration and invasion through wound healing and Transwell assays. Further studies showed that Flt1 gene knockdown inhibited the dissemination of glioblastoma cells in vivo. Conversely, the researchers also found that inhibiting Flt1 expression suppressed glioblastoma cell migration and invasion. Finally, these findings indicate that Flt1 promotes glioblastoma cell invasion and migration through the Sonic Hedgehog (SHH) signaling pathway. These studies suggest that Flt1 is a key regulator of glioblastoma cell metastasis. Therefore, detecting and targeting Flt1-expressing cancer cells could serve as a novel therapeutic target for glioblastoma.

In this study, researchers constructed an Flt1 knockdown LNT-229 cancer cell line, where the LNT-229 cell line exhibited relatively high Flt1 expression levels (Figure 1A-C). Next, the researchers investigated whether specific silencing of Flt1 affected the in vitro growth of glioblastoma cells. A solution cell proliferation assay showed that the proliferation of Flt1 knockdown LNT-229 cells was inhibited (Figure 1D). Similarly, downregulation of Flt1 in LNT-229 cells significantly reduced soft agar colony formation ability, including both the number and average size of colonies (Figure 1E). Compared to the vector control group, the growth of Flt1 knockdown LNT-229 glioblastoma cells in nude mice was inhibited (Figure 1F). To determine whether Flt1 knockdown also led to reduced in vivo metastasis of LNT-229 cells, researchers intravenously injected LNT-229 control cells or Flt1 knockdown cells into nude mice and examined lung metastasis after 12 weeks. Histological analysis showed that the number of metastatic foci produced by Flt1 knockdown cells was significantly reduced compared to the number of metastatic foci produced by control cells (Figure 1G). Finally, to determine the precise role of Flt1 in glioblastoma development and progression, researchers used Transwell and wound healing assays to examine the invasion and migration capabilities of LNT-229 cells. Functionally, compared to the control group, Flt1 inhibition significantly reduced the number of cells that migrated across the membrane (Figure 1H). Similarly, the wound healing rate was significantly reduced in Flt1 knockdown LNT-229 cells (Figure 1I).

Figure 1. Silencing Flt1 inhibits malignant progression of glioblastoma cells LNT-229. (Jiang K, et al., 2017)