Cell kinetics of human squamous cell carcinomas in the oral cavity.

Cell proliferation characteristic of human malignant tumors has been related to the responses of tumors to various therapeutic means. The present study mainly concerns a routine method to measure cell kinetic parameters in human solid tumors. Proposed for this aim is the in vitro double labeling method under hyperbaric condition. For assessment of the method, two steps were taken. First cell cycle parameters were compared in a mouse squamous cell carcinoma between this in vitro method and the in vivo percent labeled mitoses methods. Second, the in vitro method was applied to eight cases of human squamous cell carcinomas. The results indicate that two sets of the cell cycle parameters of mouse squamous cell carcinoma measured by the two methods are in good agreement within an experimental error. DNA synthesis time, labeling index and cell cycle time of human squamous cell carcinoma varied among cases with a dispersion of 2- to 3-fold, that is, with ranges of 4.1-14.0 h, 14.3-28.7% and 21.2-52.9 /, respectively.