Elemental and isotopic analysis of oral squamous cell carcinoma tissues using sector-field and multi-collector ICP-mass spectrometry.

Elemental and isotopic analysis via single-collector and multi-collector ICP-mass spectrometry, respectively, have been explored as a tool for identifying potential differences between non-tumor and oral squamous cell carcinoma tissues. Elemental concentrations of major and minor elements, known to be essential for different processes in the cell (i.e. Na, Ca, Mg, K, P, Fe, Cu and Zn), have been determined and results for cancerous and non-cancerous tissues collected from the same individual have been compared. Among the elements studied, only Mg, K and P turned out to be significantly higher in concentration in the tumor tissues. However, a shift towards higher and wider concentration ranges has also been observed for Cu and Zn in the tumor samples, whereas for Ca lower concentrations were established. Possible isotope ratio variations for Cu and Zn in both biological tissues have also been evaluated with the same goal. δ66Zn results did not provide an obvious trend, but in the case of Cu, a clear distinction between the tumor and non-tumor tissues was observed: δ65Cu values ranged between -0.68% and 0.03% in the non-tumor tissues, whereas tumor samples turned out to be enriched in 65Cu, with δ65Cu values between 0.10% and 0.93%. These results confirm the considerable potential of isotopic and elemental studies for biomedical purposes.