Therapeutic potential of histamine H4 receptor agonists in triple-negative human breast cancer experimental model

Background and Purpose

The presence of the histamine H₄ receptor (H₄R) was previously reported in benign and malignant lesions and cell lines derived from the human mammary gland. The aim of this work was to evaluate the effects of H₄R ligands on the survival, tumour growth rate and metastatic capacity of breast cancer in an experimental model.

Experimental Approach

Xenograft tumours of the highly invasive human breast cancer cell line MDA-MB-231 were established in immune deficient nude mice. The following H₄R agonists were employed: histamine (5 mg kg⁻¹), clozapine (1 mg kg⁻¹) and the experimental compound JNJ28610244 (10 mg kg⁻¹).

Results

Data indicate that developed tumours were highly undifferentiated, expressed H₄R and exhibited high levels of histamine content and proliferation marker (PCNA) while displaying low apoptosis. Mice of the untreated group displayed a median survival of 60 days and a tumour doubling time of 7.4 ± 0.6 days. A significant decrease in tumour growth evidenced by an augment of the tumour doubling time was observed in the H₄R agonist groups (13.1 ± 1.2, P < 0.01 in histamine group; 15.1 ± 1.1, P < 0.001 in clozapine group; 10.8 ± 0.7, P < 0.01 in JNJ28610244 group). This effect was associated with a decrease in the PCNA expression levels, and also reduced intratumoural vessels in histamine and clozapine treated mice. Histamine significantly increased median survival (78 days; Log rank Mantel-Cox Test, P = 0.0025; Gehan-Breslow-Wilcoxon Test, P = 0.0158) and tumoural apoptosis.

Conclusions and Implications

Histamine through the H₄R exhibits a crucial role in tumour progression. Therefore, H₄R ligands offer a novel therapeutic potential as adjuvants for breast cancer treatment.

Linked Articles

This article is part of a themed issue on Histamine Pharmacology Update. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2013.170.issue-1