TABLE 1

Comparison Between TK₁ Activity and S-Phase Percentage

Cell line	TK₁ activity (range)	S phase (%, range)	Slope (mean ± SD)	r²	P
A549	124–1,875	4.1–35.9	56.1 ± 5.7	0.96	0.002
HT29	1,125–2,597	34.4–59.8	29.0 ± 13.7	0.41	0.10
WiDr	587–2,189	12.2–51.8	45.7 ± 16.0	0.59	0.05
EMT6	38–1,380	2.2–44.4	31.4 ± 6.5	0.82	0.008
RIF1	27–283	2.8–36.3	4.8 ± 2.0	0.61	0.14
KHTn	12–199	12.2–46.4	4.3 ± 0.9	0.82	0.008

TK₁ activity is picomoles of TdR phosphorylated in 30 min per milligram of protein.