Hyaluronan synthase 2 expressed by cancer-associated fibroblasts promotes oral cancer invasion

Abstract

BackgroundHyaluronan synthases (HAS) control the biosynthesis of hyaluronan (HA) and critically modulate the tumor microenviroment. Cancer-associated fibroblasts (CAFs) affect the progression of a tumor by remolding the matrix. However, little is known about the role of HAS from CAFs in this process. This study aimed to determine the role of hyaluronan synthase 2 (HAS2) from CAFs in the progression of oral squamous cell carcinoma (OSCC) invasion.MethodsHAS isoforms 1, 2, and 3 in paired sets of CAFs and normal fibroblasts (NFs) were examined by real-time PCR, and the expression of HAS2 and α-SMA in OSCC tissue sections was further evaluated using immunohistochemical staining. Furthermore, we used a conditioned culture medium model to evaluate the effects of HAS2 from CAFs on the invasion and epithelial-mesenchymal transition (EMT) of the oral cancer cells Cal27. Finally, we compared the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) between CAFs and NF, and between CAFs with or without HAS2 knockdown using an antibody array and western blotting.ResultsCAFs expressed higher levels of HAS2 than the paired NFs. HAS2 expression was consistent with α-SMA-positive myofibroblasts in the stroma of OSCC, and these were significantly correlated advanced clinical stages and cervical lymph node metastasis. Knocking down HAS2 with a specific siRNA or treatment with a HAS inhibitor markedly attenuated CAF-induced invasion and EMT of Cal27 cells. Higher MMP1 and lower TIMP1 levels were detected in the supernatants of CAFs relative to NFs. Knocking down HAS2 could decrease the expression of MMP1 and increase that of TIMP1 in CAFs.ConclusionsHAS2 is one of the key regulators responsible for CAF-mediated OSCC progression and acts by modulating the balance of MMP1 and TIMP1.Electronic supplementary materialThe online version of this article (doi:10.1186/s13046-016-0458-0) contains supplementary material, which is available to authorized users.

Hyaluronan‐CD44/RHAMM interaction‐dependent cell proliferation and survival in lung cancer cells

“…In the present study, NSCLC cell lines predominantly expressed HAS3, whereas NHLFs and LCAFs expressed mainly HAS2, which suggests that NSCLC cells and fibroblasts synthesize low molecular weight HA and high molecular weight HA, respectively. Our observations of high HAS2 levels in CAFs are in accord with previous reports . Unlike cancer cells which are endowed with high hyaluronidase expression and activity, normal fibroblasts and CAFs lack hyaluronidases .…”

“…Our observations of high HAS2 levels in CAFs are in accord with previous reports. 25,33 Unlike cancer cells which are endowed with high hyaluronidase expression and activity, normal fibroblasts and CAFs lack hyaluronidases. 34,35 Therefore, in order to induce pro-tumorigenic effects, CAF-generated HA needs to be degraded to low molecular weight HA by hyaluronidases secreted from other cells of the tumor microenvironment.…”

Biomimetic tissue models reveal the role of hyaluronan in melanoma proliferation and invasion

“…Discussion: biomimetic models reveal alternative explanation for in vivo observation An increase of HA, especially via overexpression of HAS2, showed tumor driving properties via different mechanisms. 49,[59][60][61] Our findings fall in line with those reports, since the knockdown of Has2 led to decreased primary tumor mass. It can be assumed that knockdown of the main HMW-HA producing enzyme Has2 and only the smaller amount of existing HMW-HA would result in smaller tumors.…”

Hyaluronic Acid in the 3^rd Millennium

“…It represents the main hyaluronan synthetic enzyme in normal adult cells, and its activity is finely regulated [96]. HAS2 also regulates developmental and reparation processes of tissue growth, and it may be involved in inflammation, cancer, pulmonary fibrosis and keloid scarring [55,86,[97][98][99]. HAS3 is the most active isoenzyme, and produces HA molecules with MW lower than 3 x 10 5 Da [60].…”