Identification of Cyclophilin A as a Potential Anticancer Target of Novel Nargenicin A1 Analog in AGS Gastric Cancer Cells.

Jang Mi Han,Jae Kyung Sohng,Tae-Jin Oh,Hye Jin Jung,Woo-Haeng Lee

doi:10.3390/ijms22052473

Abstract

We recently discovered a novel nargenicin A1 analog, 23-demethyl 8,13-deoxynargenicin (compound 9), with potential anti-cancer and anti-angiogenic activities against human gastric adenocarcinoma (AGS) cells. To identify the key molecular targets of compound 9, that are responsible for its biological activities, the changes in proteome expression in AGS cells following compound 9 treatment were analyzed using two-dimensional gel electrophoresis (2-DE), followed by MALDI/TOF/MS. Analyses using chemical proteomics and western blotting revealed that compound 9 treatment significantly suppressed the expression of cyclophilin A (CypA), a member of the immunophilin family. Furthermore, compound 9 downregulated CD147-mediated mitogen-activated protein kinase (MAPK) signaling pathway, including c-Jun N-terminal kinase (JNK) and extracellular signal-regulated protein kinase 1/2 (ERK1/2) by inhibiting the expression of CD147, the cellular receptor of CypA. Notably, the responses of AGS cells to CypA knockdown were significantly correlated with the anticancer and antiangiogenic effects of compound 9. CypA siRNAs reduced the expression of CD147 and phosphorylation of JNK and ERK1/2. In addition, the suppressive effects of CypA siRNAs on proliferation, migration, invasion, and angiogenesis induction of AGS cells were associated with G2/M cell cycle arrest, caspase-mediated apoptosis, inhibition of MMP-9 and MMP-2 expression, inactivation of PI3K/AKT/mTOR pathway, and inhibition of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) expression. The specific interaction between compound 9 and CypA was also confirmed using the drug affinity responsive target stability (DARTS) and cellular thermal shift assay (CETSA) approaches. Moreover, in silico docking analysis revealed that the structure of compound 9 was a good fit for the cyclosporin A binding cavity of CypA. Collectively, these findings provide a novel molecular basis for compound 9-mediated suppression of gastric cancer progression through the targeting of CypA.

Highlights

Gastric cancer (GC) is a malignant tumor that originates from the glandular epithelium of the gastric mucosa
Our current results show that compound 9 mediates anticancer and antiangiogenic activities by downregulating the function of cyclophilin A (CypA) in AGS cells
Using 2-DE and MALDI-TOF MS analysis, we identified CypA as a crucial anticancer target of compound 9 in AGS cells for the first time

Summary

Introduction

Gastric cancer (GC) is a malignant tumor that originates from the glandular epithelium of the gastric mucosa. GC is a multifactorial disease caused by diverse environmental and genetic factors Risk factors, such as family history, diet, alcohol consumption, smoking, obesity, Helicobacter pylori infection, E-cadherin gene (CDH1) alteration, and polymorphisms of interleukin (IL-17 and IL-10) genes, are associated with a high incidence of GC [2,3,4,5]. The prognosis for advanced GC remains poor due to complex oncogenic molecular mechanisms caused by various genetic and epigenetic alterations [10]. These GC therapies, cause symptoms, such as fatigue, diarrhea, and rash, and cause fatal side effects, such as anemia, intestinal obstruction, cardiac dysfunction, and blood toxicity [9].

Methods

Findings

Discussion

Conclusion