A miRNA-145/TGF-β1 negative feedback loop regulates the cancer-associated fibroblast phenotype.

The dissemination of cancer cells to local and distant sites depends on a complex and poorly understood interplay between malignant cells and the cellular and non-cellular components surrounding them, collectively termed the tumour microenvironment. One of the most abundant cell types of the tumour microenvironment is the fibroblast, which becomes corrupted by locally derived cues such as TGF-β1 and acquires an altered, heterogeneous phenotype (cancer-associated fibroblasts, CAF) supportive of tumour cell invasion and metastasis. Efforts to develop new treatments targeting the tumour mesenchyme are hampered by a poor understanding of the mechanisms underlying the development of CAF.

Angiotensin 1-7 inhibits angiotensin II-stimulated head and neck cancer progression.

Angiotensin II (Ang II) is the product of the proteolytic action of angiotensin-converting enzyme (ACE) on the precursor peptide, angiotensin I (Ang I). In addition to its vasoactive properties, Ang II is able to stimulate angiogenesis and act as a mitogen, promoting cellular proliferation. Recently, evidence has emerged that Ang II is also able to promote tumour invasion, a key step in the metastatic cascade, although the mechanisms by which it does so remain largely obscure.

Cigarette smoke condensate promotes pro-tumourigenic stromal-epithelial interactions by suppressing miR-145.

Background: Exposure to factors released from tobacco during chewing or smoking is recognized as a major risk factor for oral carcinogenesis and influences the phenotype of oral epithelial cells and fibroblasts within the underlying stroma. Micro(mi)RNA can regulate the expression of genes within cells, and previous studies show that tobacco products can alter the miRNA profiles in lung epithelial cells. However, the molecular alterations occurring in oral fibroblasts exposed to tobacco constituents remain to be elucidated.

Endothelin-1 stimulates oral fibroblasts to promote oral cancer invasion.

Aims: The aims of this study were to examine the role of endothelin-1 (ET-1), a pleiotropic peptide found at elevated levels in a number of malignancies and which has been shown to influence oral cancer cell behaviour via paracrine signalling pathways, on the phenotype of oral fibroblasts.

Main Methods: The effect of ET-1 on proliferation and migration of human primary oral fibroblasts was assessed using MTS and scratch assays, respectively. The ability of ET-1 to affect fibroblast contractility was analysed using type-I collagen gels.

Endothelin-1 stimulates motility of head and neck squamous carcinoma cells by promoting stromal-epithelial interactions.

The invasion and migration of cancer cells is increasingly recognised to be influenced by factors derived from adjacent tumour-associated stroma. The contextual signals regulating stromal-tumour interactions, however, remain poorly understood. Here, we identify a role for endothelin-1 (ET-1), a mitogenic peptide elevated in a number of malignancies, in promoting pro-metastatic cross-talk between head and neck cancer cells and adjacent fibroblasts.

MicroRNA-124 suppresses oral squamous cell carcinoma motility by targeting ITGB1.

Alterations in the levels of molecules which interact with the extracellular matrix, such as integrins, are associated with invasion of oral squamous cell carcinomas (OSCC). The molecular mechanisms underlying dysregulation of integrin expression in OSCC, however, remain unclear. Here, we show that microRNA-124, a small non-coding RNA down-regulated in OSCC, is able to downregulate expression of integrin beta-1 (ITGB1) by interacting with its 3' untranslated region.

ECE-1 influences prostate cancer cell invasion via ET-1-mediated FAK phosphorylation and ET-1-independent mechanisms.

Plasma concentrations of the mitogenic peptide endothelin-1 (ET-1) are significantly elevated in men with metastatic prostate cancer (PC). ET-1 also contributes to the transition of hormonally regulated androgen-dependent PC to androgen-independent disease. ET-1 is generated from big-ET-1 by endothelin-converting enzyme (ECE-1).