Functional characterization of the ectopically expressed olfactory receptor 2AT4 in human myelogenous leukemia.

S Manteniotis,W Schmiegel,S Wojcik,P Brauhoff,L Petersen,M Möllmann,U Dührsen,G Gisselmann,JR Göthert,H Hatt

doi:10.1038/cddiscovery.2015.70

Abstract

The olfactory receptor (OR) family was found to be expressed mainly in the nasal epithelium. In the last two decades members of the OR family were detected to be functional expressed in different parts of the human body such as in liver, prostate or intestine cancer cells. Here, we detected the expression of several ORs in the human chronic myelogenous leukemia (CML) cell line K562 and in white blood cells of clinically diagnosed acute myeloid leukemia (AML) patients by RT-PCR and next-generation sequencing. With calcium-imaging, we characterized in greater detail the cell biological role of one OR (OR2AT4) in leukemia. In both cell systems, the OR2AT4 agonist Sandalore-evoked strong Ca2+ influx via the adenylate cyclase-cAMP-mediated pathway. The OR2AT4 antagonist Phenirat prevented the Sandalore-induced intracellular Ca2+ increase. Western blot and flow cytometric experiments revealed that stimulation of OR2AT4 reduced the proliferation by decreasing p38-MAPK phosphorylation and induced apoptosis via phosphorylation of p44/42-MAPK. Furthermore, Sandalore increased the number of hemoglobin-containing cells in culture. We described for the first time an OR-mediated pathway in CML and AML that can regulate proliferation, apoptosis and differentiation after activation. This mechanism offers novel therapeutic options for the treatment of AML.

Highlights

Despite improvements in supportive care and allogeneic transplantation, acute myeloid leukemia (AML) is cured in o50% of patients younger than 60 years old and o20% of patients older than 60 years old.[1]
For the initial detection of ectopically expressed olfactory receptors (OR) in myelogenous leukemia, we reanalyzed a free online available NGS data set from the chronic myelogenous leukemia (CML) cell line K562 (SRR1207231)
Same ORs were found in cell types. (e) Immunofluorescence staining of OR2AT4 in K562 cells was analyzed with a confocal microscope

Summary

Introduction

Despite improvements in supportive care and allogeneic transplantation, acute myeloid leukemia (AML) is cured in o50% of patients younger than 60 years old and o20% of patients older than 60 years old.[1]. To investigate whether Sandalore could activate the OR2AT4 in K562 cells, long-term (10 min) calcium-imaging experiments with 300 μM Sandalore were performed and revealed that the cells increased temporary their intracellular Ca2+ level within the first 2 min during odor application (Figure 2a).

Results

Conclusion