Cytokine expression and synthesis in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) was evaluated for the expression of tum our necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6). Noncarcinom atous tissues without signs of inflammatory changes served as controls. Ele vated levels of TNF-alpha and IL-6 proteins and their upregulated mRNA leve ls were demonstrated in OSCC tissues compared to those in controls. These c ytokines and their transcripts were localised in stromal macrophages and in the tumour cells in particular of advanced area of tumour tissues, indicat ing synthesis of these cytokines by tumour cells. The expression levels of the cytokines were significantly reduced in cases with effective pretreatme nt compared to those in the less effective group (p < 0.05, grade IV vs. gr ade IIa for both TNF-alpha and IL-6). The present study thus, provides evid ence that tumour cells themselves produce cytokines, by which local tumour growth and invasion may be regulated in a manner of autocrine and/or paracr ine system.