The angiotensin receptor blocker, Losartan, inhibits mammary tumor development and progression to invasive carcinoma

Drugs that target the Renin-Angiotensin System (RAS) have recently come into focus for their potential utility as cancer treatments. The use of Angiotensin Receptor Blockers (ARBs) and Angiotensin-Converting Enzyme (ACE) Inhibitors (ACEIs) to manage hypertension in cancer patients is correlated with improved survival outcomes for renal, prostate, breast and small cell lung cancer. Previous studies demonstrate that the Angiotensin Receptor Type I (AT1R) is linked to breast cancer pathogenesis, with unbiased analysis of gene-expression studies identifying significant up-regulation of AGTR1, the gene encoding AT1R in ER+ve/HER2-ve tumors correlating with poor prognosis. However, there is no evidence, so far, of the functional contribution of AT1R to breast tumorigenesis. We explored the potential therapeutic benefit of ARB in a carcinogen-induced mouse model of breast cancer and clarified the mechanisms associated with its success.Mammary tumors were induced with 7,12-dimethylbenz[α]antracene (DMBA) and medroxyprogesterone acetate (MPA) in female wild type mice and the effects of the ARB, Losartan treatment assessed in a preventative setting (n = 15 per group). Tumor histopathology was characterised by immunohistochemistry, real-time qPCR to detect gene expression signatures, and tumor cytokine levels measured with quantitative bioplex assays. AT1R was detected with radiolabelled ligand binding assays in fresh frozen tumor samples.We showed that therapeutic inhibition of AT1R, with Losartan, resulted in a significant reduction in tumor burden; and no mammary tumor incidence in 20% of animals. We observed a significant reduction in tumor progression from DCIS to invasive cancer with Losartan treatment. This was associated with reduced tumor cell proliferation and a significant reduction in IL-6, pSTAT3 and TNFα levels. Analysis of tumor immune cell infiltrates, however, demonstrated no significant differences in the recruitment of lymphocytes or tumour-associated macrophages in Losartan or vehicle-treated mammary tumors.Analysis of AT1R expression with radiolabelled ligand binding assays in human breast cancer biopsies showed high AT1R levels in 30% of invasive ductal carcinomas analysed. Furthermore, analysis of the TCGA database identified that high AT1R expression to be associated with luminal breast cancer subtype.Our in vivo data and analysis of human invasive ductal carcinoma samples identify the AT1R is a potential therapeutic target in breast cancer, with the availability of a range of well-tolerated inhibitors currently used in clinics. We describe a novel signalling pathway critical in breast tumorigenesis, that may provide new therapeutic avenues to complement current treatments.

Errataetall:

CommentIn: Oncotarget. 2017 Mar 21;8(12):18618-18619. - PMID 28423631

Medienart:

E-Artikel

Erscheinungsjahr:

2017

Erschienen:

2017

Enthalten in:

Zur Gesamtaufnahme - volume:8

Enthalten in:

Oncotarget - 8(2017), 12 vom: 21. März, Seite 18640-18656

Sprache:

Englisch

Beteiligte Personen:

Coulson, Rhiannon [VerfasserIn]
Liew, Seng H [VerfasserIn]
Connelly, Angela A [VerfasserIn]
Yee, Nicholas S [VerfasserIn]
Deb, Siddhartha [VerfasserIn]
Kumar, Beena [VerfasserIn]
Vargas, Ana C [VerfasserIn]
O'Toole, Sandra A [VerfasserIn]
Parslow, Adam C [VerfasserIn]
Poh, Ashleigh [VerfasserIn]
Putoczki, Tracy [VerfasserIn]
Morrow, Riley J [VerfasserIn]
Alorro, Mariah [VerfasserIn]
Lazarus, Kyren A [VerfasserIn]
Yeap, Evie F W [VerfasserIn]
Walton, Kelly L [VerfasserIn]
Harrison, Craig A [VerfasserIn]
Hannan, Natalie J [VerfasserIn]
George, Amee J [VerfasserIn]
Clyne, Colin D [VerfasserIn]
Ernst, Matthias [VerfasserIn]
Allen, Andrew M [VerfasserIn]
Chand, Ashwini L [VerfasserIn]

Links:

Volltext

Themen:

57-97-6
9,10-Dimethyl-1,2-benzanthracene
Angiotensin II Type 1 Receptor Blockers
Angiotensin receptor
C2QI4IOI2G
Interleukin 6
Interleukin-6
Interleukin-6, mouse
Invasive ductal carcinoma
JMS50MPO89
Journal Article
Losartan
Luminal breast cancer
Medroxyprogesterone Acetate
Receptor, Angiotensin, Type 1
STAT3 Transcription Factor
Stat3 protein, mouse
Tumor Necrosis Factor-alpha
Tumor necrosis factor

Anmerkungen:

Date Completed 04.12.2017

Date Revised 08.04.2022

published: Print

CommentIn: Oncotarget. 2017 Mar 21;8(12):18618-18619. - PMID 28423631

Citation Status MEDLINE

doi:

10.18632/oncotarget.15553

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM271037970