Relevance of CCL3/CCR5 axis in oral carcinogenesis.

The chemokine CCL3 is a chemotactic cytokine crucial for inflammatory cell recruitment in homeostatic and pathological conditions. CCL3 might stimulate cancer progression by promoting leukocyte accumulation, angiogenesis and tumour growth. The expression of CCL3 and its receptors CCR1 and CCR5 was demonstrated in oral squamous cell carcinoma (OSCC), but their role was not defined. Here, the functions of CCL3 were assessed using a model of chemically induced tongue carcinogenesis with 4-nitroquinoline-1-oxide (4NQO). Lineages of OSCC were used to analyse the effects of CCL3 in vitro. The 4NQO-induced lesions exhibited increased expression of CCL3, CCR1 and CCR5. CCL3-/- and CCR5-/- mice presented reduced incidence of tongue tumours compared to wild-type (WT) and CCR1-/- mice. Consistently, attenuated cytomorphological atypia and reduced cell proliferation were observed in lesions of CCL3-/- and CCR5-/- mice. OSCC from CCL3-/- mice exhibited lower infiltration of eosinophils and reduced expression of Egf, Fgf1, Tgf-ß1, Vegfa, Vegfb, Itga-4, Vtn, Mmp-1a, Mmp-2 and Mmp-9 than WT mice. In vitro, CCL3 induced invasion and production of CCL5, IL-6, MMP -2, -8, -9. Blockage of CCL3 in vitro using α-CCL3 or Evasin-1 (a CCL3-binding protein) impaired tumour cell invasion. In conclusion, CCL3/CCR5 axis has pro-tumourigenic effects in oral carcinogenesis. The induction of inflammatory and angiogenic pathways and eosinophils recruitment appear to be the underlying mechanism explaining these effects. These data reveal potential protective effects of CCL3 blockade in oral cancer.

Significance of chemokine and chemokine receptors in head and neck squamous cell carcinoma: A critical review.

Chemokines are small chemotactic proteins that coordinate circulation of immune/inflammatory cells throughout body compartments. Because of this property chemokines and their cell surface receptors are implicated in several physiological and pathological conditions, including cancer. These molecules are expressed by neoplastic or stromal cells and have effects at tumor primary site (e.g. stimulating angiogenesis and tumor cells motility) and lymph nodes (creating a gradient to direct migration of neoplastic cells). In this article we review the current knowledge about the function(s) of chemokines and receptors in squamous cell carcinoma from the oral cavity and head and neck region. Accumulating evidence suggests some chemokine(s) and receptor(s) as potential targets in adjuvant therapies for these malignancies.

Effect of salivary stimulation therapies on salivary flow and chemotherapy-induced mucositis: a preliminary study.

OBJECTIVE: The objective of this study was to evaluate the effect of salivary stimulation therapies on the salivary flow, oral mucositis, and salivary cytokine levels in patients receiving allogeneic hematopoietic stem cell transplantation. STUDY DESIGN: Thirty-five eligible patients were randomized into 4 groups: control, mechanical sialogogue, transcutaneous electrical nerve stimulation (TENS) sialogogue, and combined mechanical/electrical sialogogue. Saliva was collected from patients before transplantation and at days 3, 7, and 14 after transplantation. The volume was measured and salivary cytokines were assessed using enzyme-linked immunosorbent assay. RESULTS: By day 14, resting and stimulated salivary flow levels were diminished. Resting salivary flow rates decreased the most in the control and mechanical groups. In contrast, TENS alone or in combination with mechanical stimulatory therapy benefited the patients. TENS-treated patients showed increase in resting salivary flow. Also, the groups treated with TENS had fewer patients affected by grades 3 and 4 mucositis, and less mucositis was associated with better patient survival (P = .027). CONCLUSIONS: TENS-associated salivary stimulation therapies minimized the reduction of salivary flow and prevented severe chemotherapy-induced oral mucositis.