Objective: The aim of this study was to determine expression patterns of a range of cell cycle proteins in metastatic and non-metastatic carcinomas, and evaluate their potential as prognostic biomarkers
Method:
A total of 127 samples were studied. There were 47 primary OSCC which had not metastasised (NM) and 40 that had metastsised (M), with their matched positive cervical lymph nodes. Tissue microarrays (TMAs) were prepared (Beecher manual micro-array system) with three cores from each of three areas: surface, middle and advancing front of each case. Sections were immunostained with MCM2, Ki-67, Geminin, Cyclin D1 and p16 antibodies. Expression was measured semi-quantitatively based on intensity and extent of staining (“quickscore” (Q) method).
Result: There were no differences in expression in each area of the tumours, nor between the NM and M groups, except for MCM2, which was significantly higher in OSCC M. For all cell cycle proteins except p16, expression was significantly higher in the OSCC M than in their matched lymph nodes (Mann-Whitney p<0.001).
Conclusion:
OSCC appear to be homogeneous with regards to cell cycle protein expression. Only MCM2 was more highly expressed in tumours that metastasised suggesting that this marker may have prognostic significance. Higher expression in primary lesions than lymph nodes supports the view that metastatic lesions may be better differentiated.