The interaction between CD44 on tumour cells and hyaluronan under physiologic flow conditions: implications for metastasis formation.
Richter Ulrich,Wicklein Daniel,Geleff Silvana,Schumacher Udo
Histochemistry and cell biology
The adhesion of tumour cells to the endothelial cells of blood vessels of the microcirculation represents a crucial step in haematogenous metastasis formation. Similar to leukocyte extravasation, selectins mediate initial tumour cell rolling on endothelium. An additional mechanism of leukocyte adhesion to endothelial cells is mediated by hyaluronan (HA). However, data on the interaction of tumour cells with hyaluronan under shear stress are lacking. The expression of the hyaluronan binding protein CD44 on tumour cell surfaces was evaluated using flow cytometry. The adhesion of tumour cells to HA with regard to adhesive events and rolling velocity was determined in flow assays in the human small cell lung cancer (SCLC) cell lines SW2, H69, H82, OH1 and OH3, the colon carcinoma cell line HT29 and the melanoma cell line MeWo. Hyaluronan deposition in human and mouse lung blood vessels was histochemically determined. MeWo adhered best to HA followed by HT29. SCLC cell lines showed the lowest CD44 expression on the cell surface and lowest number of adhesive events. While hyaluronan was deposited in patches in the microvasculature of the alveolar septum in the human lung, it was only present in the periarterial space in the mouse lung. Certain tumour entities bind to HA under physiological shear stresses so that HA can be considered a further ligand for cell extravasation in haematogenous metastasis. As hyaluronan is deposited within the pulmonary microvasculature, it may well serve as a ligand for its binding partner CD44, which is expressed by many tumour cells.
Roles and targeting of the HAS/hyaluronan/CD44 molecular system in cancer.
Karousou Evgenia,Misra Suniti,Ghatak Shibnath,Dobra Katalin,Götte Martin,Vigetti Davide,Passi Alberto,Karamanos Nikos K,Skandalis Spyros S
Matrix biology : journal of the International Society for Matrix Biology
Synthesis, deposition, and interactions of hyaluronan (HA) with its cellular receptor CD44 are crucial events that regulate the onset and progression of tumors. The intracellular signaling pathways initiated by HA interactions with CD44 leading to tumorigenic responses are complex. Moreover, HA molecules may perform dual functions depending on their concentration and size. Overexpression of variant isoforms of CD44 (CD44v) is most commonly linked to cancer progression, whereas their loss is associated with inhibition of tumor growth. In this review, we highlight that the regulation of HA synthases (HASes) by post-translational modifications, such as O-GlcNAcylation and ubiquitination, environmental factors and the action of microRNAs is important for HA synthesis and secretion in the tumor microenvironment. Moreover, we focus on the roles and interactions of CD44 with various proteins that reside extra- and intracellularly, as well as on cellular membranes with particular reference to the CD44-HA axis in cancer stem cell functions, and the importance of CD44/CD44v6 targeting to inhibit tumorigenesis.
Hyaluronan-CD44/RHAMM interaction-dependent cell proliferation and survival in lung cancer cells.
Song Jung Min,Im Jintaek,Nho Richard Seonghun,Han Yong Hwan,Upadhyaya Pramod,Kassie Fekadu
Although members of the hyaluronan (HA)-CD44/HA-mediated motility receptor (RHAMM) signaling pathway have been shown to be overexpressed in lung cancer, their role in lung tumorigenesis is unclear. In the present study, we first determined levels of HA and its receptors CD44 and RHAMM in human non-small cell lung cancer (NSCLC) cells and stromal cells as well as mouse lung tumors. Subsequently, we examined the role of HA-CD44/RHAMM signaling pathway in mediating the proliferation and survival of NSCLC cells and the cross-talk between NSCLC cells and normal human lung fibroblasts (NHLFs)/lung cancer-associated fibroblasts (LCAFs). The highest levels of HA and CD44 were observed in NHLFs/LCAFs followed by NSCLC cells, whereas THP-1 monocytes/macrophages showed negligible levels of both HA and CD44. Simultaneous silencing of HA synthase 2 (HAS2) and HAS3 or CD44 and RHAMM suppressed cell proliferation and survival as well as the EGFR/AKT/ERK signaling pathway. Exogenous HA partially rescued the defect in cell proliferation and survival. Moreover, conditioned media (CM) generated by NHLFs/LCAFs enhanced the proliferation of NSCLC cells in a HA-dependent manner as treatment of NHLFs and LCAFs with HAS2 siRNA, 4-methylumbelliferone, an inhibitor of HASs, LY2228820, an inhibitor of p38MAPK, or treatment of A549 cells with CD44 blocking antibody suppressed the effects of the CM. Upon incubation in CM generated by A549 cells or THP-1 macrophages, NHLFs/LCAFs secreted higher concentrations of HA. Overall, our findings indicate that targeting the HA-CD44/RHAMM signaling pathway could be a promising approach for the prevention and therapy of lung cancer.
Hyaluronan-CD44 axis orchestrates cancer stem cell functions.
Skandalis Spyros S,Karalis Theodoros T,Chatzopoulos Athanasios,Karamanos Nikos K
The prominent role of CD44 in tumor cell signaling together with its establishment as a cancer stem cell (CSC) marker for various tumor entities imply a key role for CD44 in CSC functional properties. Hyaluronan, the main ligand of CD44, is a major constituent of CSC niche and, therefore, the hyaluronan-CD44 signaling axis is of functional importance in this special microenvironment. This review aims to provide recent advances in the importance of hyaluronan-CD44 interactions in the acquisition and maintenance of a CSC phenotype. Hyaluronan-CD44 axis has a substantial impact on stemness properties of CSCs and drug resistance through induction of EMT program, oxidative stress resistance, secretion of extracellular vesicles/exosomes and epigenetic control. Potential therapeutic approaches targeting CSCs based on the hyaluronan-CD44 axis are also presented.
Hyaluronan-CD44 interaction promotes HPV 16 E6 oncogene-mediated oropharyngeal cell carcinoma survival and chemoresistance.
Bourguignon Lilly Y W,Earle Christine,Shiina Marisa
Matrix biology : journal of the International Society for Matrix Biology
Head and neck squamous cell carcinoma (HNSCC) is a malignancy that often involves the oral cavity, pharynx, larynx, or paranasal sinuses. There is a compelling evidence of the human papilloma virus including HPV16 E6 oncogene drives cell transformation and oncogenic processes of HPV positive (HVP+) HNSCC [in particular, Oropharyngeal Squamous Cell Carcinoma (OPSCC)]. In this study, we determined that human OPSCC-derived, HPV16 E6+ cells (UMSCC-104 and UMSCC-47 cell lines) express CD44 and a regulatory transcription factor, c-Jun. Importantly, interaction between matrix hyaluronan (HA) and CD44 (an HA receptor) promotes c-Jun phosphorylation followed by phospho-c-Jun nuclear translocation and co-localization with HPV16 E6 in the nucleus of both UMSCC-104 and UMSCC-47 cells. Further analyses revealed that HPV16 E6 expression is regulated by an upstream promoter containing AP1/c-Jun binding site(s), and chromatin immunoprecipitation (ChIP) assays demonstrated that stimulation of HPV16 E6 expression by HA-CD44 interaction is phospho-c-Jun dependent in these HPV16+ UMSCC-104 and UMSCC-47 cells. This process results in an upregulation of survival proteins, inhibitors of the apoptosis family of proteins (IAPs) and chemoresistance in these HPV16+ cells. Treatment of UMSCC-104 or UMSCC-47 cells with c-Jun-specific or HPV16 E6-specific small interfering RNAs effectively blocks HA/CD44-mediated c-Jun signaling and abrogates HPV16 E6 expression as well as causes downregulation of survival proteins (cIAP-1 and cIAP-2) expression and enhancement of chemosensitivity. Together, these findings suggest that the HA/CD44-induced c-Jun signaling plays a pivotal role in HPV16 E6 upregulation leading to survival protein (cIAP-1/cIAP-2) production and chemoresistance in HPV16+ UMSCC-104 and UMSCC-47 cells. Most importantly, using a mouse xenograft model, we have observed that Cisplatin chemotherapy combined with the suppression of CD44, c-Jun and HPV16 E6 (by treating both UMSCC-104 cells and UMSCC-47 cells with CD44shRNA or c-Jun shRNA or HPV16 E6 shRNA) appears to be more effective in tumor size reduction than chemotherapy alone. Thus, these newly-discovered HA/CD44-c-Jun/HPV16E6 signaling pathways may provide new drug targets for overcoming cisplatin chemoresistance in HPV16E6-positive OPSCC cells.