TABLE 2 Summary of IC_{50} values of endogenous nucleosides on [^{3}H]uridine uptake in HeLa cells

An extra-sum of squares F test (P < 0.05) was done on the best fit lines generated from the nonlinear regression IC_{50} (eq. 3) to compare generated IC_{50} values on GraphPad Prism 7. A statistically significant difference between the IC_{50} values for inosine and cytidine was found (P = 0.0137 and P < 0.0001). No statistical difference was observed for adenosine (P = 0.8384), guanosine (P = 0.7952), and thymidine (P = 0.0574). All values are reported as mean ± S.E.M. of triplicate values (n = 3).