Inhibition of Mast Cell-Derived Histamine Decreases Human Cholangiocarcinoma Growth and Differentiation via c-Kit/Stem Cell Factor–Dependent Signaling

Abstract

The tumor microenvironment of cholangiocarcinoma (CCA) is composed of numerous cells, including mast cells (MCs). MCs release histamine, which increases CCA progression and angiogenesis. Cholangiocytes secrete stem cell factor, which functions via the MC growth factor receptor c-Kit. Here, we show that cholangiocytes express histidine decarboxylase and its inhibition reduces CCA growth. MC recruitment in the tumor microenvironment increased CCA growth. MC infiltration and MC markers were detected by toluidine blue staining and real-time PCR in human biopsies and in tumors from athymic mice treated with saline, histamine, histidine decarboxylase inhibitor, or cromolyn sodium. Tumor growth, angiogenesis, and epithelial-mesenchymal transition (EMT)/extracellular matrix (ECM) markers were measured in mice treated with cromolyn sodium. In vitro, human CCA cells were treated with MC supernatant fluids before evaluating angiogenesis and EMT/ECM expression. Migration assays were performed with CCA cells treated with the stem cell factor inhibitor. MC supernatant fluids increased CCA histidine decarboxylase, vascular endothelial growth factor, and MC/EMT/ECM expression that decreased with pretreatment of cromolyn sodium. MCs were found in human biopsies. In mice treated with cromolyn sodium, MC infiltration and tumor growth decreased. Inhibition of CCA stem cell factor blocked MC migration and MC/EMT/ECM in CCA. MCs migrate into CCA tumor microenvironment via c-Kit/stem cell factor and increase tumor progression, angiogenesis, EMT switch, and ECM degradation. Cholangiocarcinoma (CCA) cancers are primary tumors that arise from the neoplastic transformation of cholangiocytes, the epithelial cells lining the intrahepatic and extrahepatic bile ducts of the liver.1 CCA is the second most prevalent liver tumor after hepatocellular carcinoma and accounts for 10% to 20% of deaths caused by hepatobiliary malignancies.2 Increased risk of developing CCA is associated with primary sclerosing cholangitis, liver fluke infestation, hepatitis C virus infection, and other diseases that lead to chronic biliary obstruction and inflammation.3 CAA is a metastatic cancer, and studies have found its potential to migrate outside of the biliary tract. 4 We have found that histamine via the H4 histamine receptor (HR)

Epithelial-mesenchymal transition in cholangiocarcinoma: From clinical evidence to regulatory networks

“…Inhibition of mast cell-derived histamine prevents EMT switch and ECM breakdown in CCA cells through H1HR and H2HR [141]. Moreover, if the SCF/Kit pathway involved in tumor mast cell recruitment is inhibited, the paracrine influence of mast cells on CCA is vanished [141], suggesting a role of mast cells/tumor cells interaction in the promotion of EMT and progression of CCA.…”

Isolation and characterization of hepatic mast cells from cholestatic rats

“…Prior to isolation of mast cells, we performed toluidine blue staining and staining in livers from normal rats and BDL rats (6 hr to 14 days post BDL) to verify the presence and localization of hepatic mast cells(12, 14). To perform toluidine blue staining, paraffin-embedded livers were sliced (4–5 μm) and deparaffanized prior to toluidine blue staining.…”

“…Traditionally, mast cell activation occurs via typical IgE/FCεRI receptor binding, however mast cells can also be triggered by the activation of the numerous ligands and G-protein coupled receptors found on their surface including histamine receptors (H1–H4)(10, 11). We have recently demonstrated that mast cell activation and chemoattraction occurs via a stem cell factor/c-kit interaction during cholangiocarcinoma progression(12). …”

“…We have demonstrated that mast cells infiltrate the liver following bile duct ligation (BDL) and that blocking mast cell-derived histamine using cromolyn sodium decreases biliary mass, proliferation and histamine secretion(14). Further, human cholangiocarcinoma tumors exhibit large numbers of mast cells and cromolyn sodium decreases tumor growth(12). Based on these observations we surmise that mast cells play an important role in liver pathology and because there are no successful techniques to isolate and examine intact mast cells from mature rat livers, our aim of this study was to isolate and characterize hepatic mast cells from cholestatic rodent livers.…”

The Hidden Side of Disodium Cromolyn: from Mast Cell Stabilizer to an Angiogenic Factor and Antitumor Agent

“…Gabexate mesylate, nafamostat mesylate, and tranilast are mast cells inhibitors recently studied as new promising antiangiogenic agents (Ammendola et al 2014). Disodium cromolyn, another mast cell stabilizer, has a widely accepted antitumor effects in several tumor types as cholangiocarcinoma (Johnson et al 2016), pancreatic cancer (Kim et al 2012) or breast malignancies (Samoszuk and Corwin 2003). All effects of mast cell stabilizers described above are related with mast cells inhibition.…”