Expression of the metalloproteases MMP-1, MMP-2, MMP-3, MMP-9, MMP-11, TIMP-1 and TIMP-2 in angiocentric midfacial lymphomas

Expression of MMP-1/PAR-1 and patterns of invasion in oral squamous cell carcinoma as potential prognostic markers

Background

Matrix metalloproteinase (MMP)-1 degrades type I collagen of the extracellular matrix and also activates protease activated receptor (PAR)-1 to induce angiogenesis. The aims of this study were to evaluate microvessel density (MVD) and the expression of PAR-1 and MMP-1 in oral squamous cell carcinoma (SCC) specimens with different patterns of invasion (POI) and to evaluate their association with clinical outcomes.

Methods

Seventy-four surgically obtained oral SCC samples were classified by POI according to hematoxylin-eosin staining. MVD and the localization and intensity of PAR-1 and MMP-1 expression were detected by immunohistochemistry.

Results

Of the 74 oral SCC samples, 18, 5, 34, and 17 showed type I, II, III, and IV POI, respectively. MVD and expression levels of MMP-1 and PAR-1 differed between POI types I–II and POI types III–IV. Patients with low tumor expression of MMP-1 and PAR-1 and low MVD had a longer survival time than those with high tumor expression of MMP-1 and PAR-1. Moreover, the survival time of patients with POI types III–IV was shorter than that of patients with POI types I–II.

Conclusion

POI combined with expression levels of MMP-1 and PAR-1 may be a valuable tool for assessing the clinical prognosis of patients with oral SCC.

MicroRNA profiling of Epstein-Barr virus-associated NK/T-cell lymphomas by deep sequencing

The Epstein-Barr virus (EBV) is an oncogenic human Herpes virus involved in the pathogenesis of nasal NK/T-cell lymphoma. EBV encodes microRNAs (miRNAs) and induces changes in the host cellular miRNA profile. MiRNAs are short non-coding RNAs of about 19–25 nt length that regulate gene expression by post-transcriptional mechanisms and are frequently deregulated in human malignancies including cancer. The microRNA profiles of EBV-positive NK/T-cell lymphoma, non-infected T-cell lymphoma and normal thymus were established by deep sequencing of small RNA libraries. The comparison of the EBV-positive NK/T-cell vs. EBV-negative T-cell lymphoma revealed 15 up- und 16 down-regulated miRNAs. In contrast, the majority of miRNAs was repressed in the lymphomas compared to normal tissue. We also identified 10 novel miRNAs from known precursors and two so far unknown miRNAs. The sequencing results were confirmed for selected miRNAs by quantitative Real-Time PCR (qRT-PCR). We show that the proinflammatory cytokine interleukin 1 alpha (IL1A) is a target for miR-142-3p and the oncogenic BCL6 for miR-205. MiR-142-3p is down-regulated in the EBV-positive vs. EBV-negative lymphomas. MiR-205 was undetectable in EBV-negative lymphoma and strongly down-regulated in EBV-positive NK/T-cell lymphoma as compared to thymus. The targets were confirmed by reporter assays and by down-regulation of the proteins by ectopic expression of the cognate miRNAs. Taken together, our findings demonstrate the relevance of deregulated miRNAs for the post-transcriptional gene regulation in nasal NK/T-cell lymphomas.

Galectin-3 facilitates cell motility in gastric cancer by up-regulating protease-activated receptor-1 (PAR-1) and matrix metalloproteinase-1 (MMP-1)

BACKGROUND

Galectin-3 is known to regulate cancer metastasis. However, the underlying mechanism has not been defined. Through the DNA microarray studies after galectin-3 silencing, we demonstrated here that galectin-3 plays a key role in up-regulating the expressions of protease-activated receptor-1 (PAR-1) and matrix metalloproteinase-1 (MMP-1) PAR-1 thereby promoting gastric cancer metastasis.

METHODOLOGY/PRINCIPAL FINDINGS

We examined the expression levels of Galectin-3, PAR-1, and MMP-1 in gastric cancer patient tissues and also the effects of silencing these proteins with specific siRNAs and of over-expressing them using specific lenti-viral constructs. We also employed zebrafish embryo model for analysis of in vivo gastric cancer cell invasion. These studies demonstrated that: a) galectin-3 silencing decreases the expression of PAR-1. b) galectin-3 over-expression increases cell migration and invasion and this increase can be reversed by PAR-1 silencing, indicating that galectin-3 increases cell migration and invasion via PAR-1 up-regulation. c) galectin-3 directly interacts with AP-1 transcriptional factor, and this complex binds to PAR-1 promoter and drives PAR-1 transcription. d) galectin-3 also amplifies phospho-paxillin, a PAR-1 downstream target, by increasing MMP-1 expression. MMP-1 silencing blocks phospho-paxillin amplification and cell invasion caused by galectin-3 over-expression. e) Silencing of either galectin-3, PAR-1 or MMP-1 significantly reduced cell migration into the vessels in zebrafish embryo model. f) Galectin-3, PAR-1, and MMP-1 are highly expressed and co-localized in malignant tissues from gastric cancer patients.

CONCLUSIONS/SIGNIFICANCE

Galectin-3 plays the key role of activating cell surface receptor through production of protease and boosts gastric cancer metastasis. Galectin-3 has the potential to serve as a useful pharmacological target for prevention of gastric cancer metastasis.

Carcinoma-associated fibroblasts promoted tumor spheroid invasion on a microfluidic 3D co-culture device

Carcinoma-associated fibroblasts (CAFs) are a key determinant in malignant progression of cancer and represent an important target for cancer therapies. In this work, we present a microfluidic-based 3D co-culture device to reconstruct an in vitro tumor microenvironment and firstly investigate the effect of CAFs on cancer cell invasion in 3D matrix. This device is composed of six co-culture units, which enable parallel co-culture assays to be run in the presence of 3D extracellular matrix. Salivary gland adenoid cystic carcinoma (ACC) cells and CAFs embedded in matrix were co-cultured without direct contact on the device. Communication between ACC cells and CAFs could be established via medium diffused in matrix. It was observed that CAFs promoted ACC cell invasion in 3D matrix in a spheroid fashion, indicating that CAFs play a critical role in cancer invasion. We further demonstrated the effect of MMP inhibitor as an agent against CAF-promoted cancer invasion. This co-culture device reproducibly reflected the in vivo growth and invasion pattern of ACC and recreated the stroma-regulated ACC invasion. Thus, it provides a suitable platform for elucidating the mechanism of CAF-regulated cancer invasion and discovering anti-invasion drugs in a well defined 3D environment.