FGFR4 Inhibitor BLU9931 Attenuates Pancreatic Cancer Cell Proliferation and Invasion While Inducing Senescence: Evidence for Senolytic Therapy Potential in Pancreatic Cancer

Abstract

Fibroblast growth factor receptor 4 (FGFR4), one of four tyrosine kinase receptors for FGFs, is involved in diverse cellular processes. Activation of FGF19/FGFR4 signaling is closely associated with cancer development and progression. In this study, we examined the expression and roles of FGF19/FGFR4 signaling in human pancreatic ductal adenocarcinoma (PDAC). In human PDAC cases, FGFR4 expression positively correlated with larger primary tumors and more advanced stages. Among eight PDAC cell lines, FGFR4 was expressed at the highest levels in PK-1 cells, in which single-nucleotide polymorphism G388R in FGFR4 was detected. For inhibition of autocrine/paracrine FGF19/FGFR4 signaling, we used BLU9931, a highly selective FGFR4 inhibitor. Inhibition of signal transduction through ERK, AKT, and STAT3 pathways by BLU9931 reduced proliferation in FGF19/FGFR4 signaling-activated PDAC cells. By contrast, BLU9931 did not alter stemness features, including stemness marker expression, anticancer drug resistance, and sphere-forming ability. However, BLU9931 inhibited cell invasion, in part, by downregulating membrane-type matrix metalloproteinase-1 in FGF19/FGFR4 signaling-activated PDAC cells. Furthermore, downregulation of SIRT1 and SIRT6 by BLU9931 contributed to senescence induction, priming these cells for quercetin-induced death, a process termed senolysis. Thus, we propose that BLU9931 is a promising therapeutic agent in FGFR4-positive PDAC, especially when combined with senolysis (195/200).

TGF-β1 increases cellular invasion of colorectal neuroendocrine carcinoma cell line through partial epithelial-mesenchymal transition

“…Immunoblotting was performed as described previously [ 15 , 16 ]. The following primary antibodies were used: monoclonal rabbit anti-pSmad2 (#3108; Cell Signaling Technology, Danvers, MA, USA), monoclonal rabbit anti-pSmad3 (ab52903; Abcam, Cambridge, UK), monoclonal rabbit anti-Smad2/3 (#8685; Cell Signaling Technology), polyclonal anti-TGFβR-I (SAB4502958; Sigma-Aldrich, St. Louis, MO, USA), polyclonal anti-TGFβR-II (sc-220; Santa Cruz Biotechnology, Dallas, TX, USA), monoclonal mouse anti-α2-integrin (sc-74466; Santa Cruz Biotechnology), and monoclonal mouse anti-β-actin (A5316; Sigma-Aldrich).…”

“…qRT-PCR analysis was performed as described previously [ [15] , [16] , [17] ]. Total RNA was isolated from cells using a RNeasy Plus Mini Kit (QIAGEN, Hilden, Germany) and was subsequently reverse-transcribed using the ReverTra Ace® qPCR RT Kit (Toyobo, Osaka, Japan).…”

“…Invasion assays were performed as described previously [ [15] , [16] , [17] ]. Cell culture inserts (pore size: 12 μm; diameter: 12 mm; Merck Millipore, Ltd., County Cork, Ireland) were coated with 80 μl of 2% Matrigel (Becton Dickinson, Franklin Lakes, NJ, USA) and used for the assay.…”

Gangliosides as Signaling Regulators in Cancer

“…In conclusion, we presented the possibility of cancer therapy that targets gangliosides, which are known to contribute to the regulation of cancer cell signaling. In recent years, near-infrared photoimmunotherapy (NIR-PIT) targeting cancer cell antigens and induction of senescence in cancer cells have gained momentum [ 91 , 92 , 93 ]. In the future, novel therapies for cancer cells expressing gangliosides, such as NIR-PIT using ganglioside-specific antibodies, as well as senolysis of senescence-induced cancer cells through ganglioside-mediated signaling, could be employed as promising therapeutic strategies.…”

Molecular aspects of pancreatic cancer: focus on reprogrammed metabolism in a nutrient-deficient environment and potential therapeutic targets

“…In addition, these studies indicated the significant importance of GOT2 in senescence regulation of PDAC, which may have new therapeutic implications. Senescence has been proposed to be an important tumor-suppressive mechanism [ 63 , 64 ] and a selective fibroblast growth factor receptor 4 (FGFR4) inhibitor (BLU9931) reduced PDAC cell proliferation and invasion while promoting their senescence [ 65 ]. Targeting FGFR4 overexpressed in half of PDACs in combination with senolysis (e.g., quercetin) could provide a novel therapeutic strategy in pancreatic cancer patients.…”