Table 1.

CI of irradiation with cisplatin in the three cell lines. Data are presented as the mean of three determinations. The sensitizing effect is <1.0 in the CI [17]

Cell	Cisplatin (μM)	X-Ray + cisplatin		Proton + cisplatin
		Dose (Gy)	CI	Dose (GyE)	CI
HSG	0.25	2	1.04	2	1.01
	0.5		1.12		1.12
	1.5		1.1		0.99
	2.5		0.82		0.86
	0.25	5	0.84	5	0.86
	0.5		0.79		0.83
	1.5*		0.48		0.68
	2.5		0.33		0.39
EMT6	0.25	2	1.21	2	1.47
	0.5		1.28		1.23
	1.5*		1		0.89
	2.5*		0.73		0.54
	0.25	5	0.94	5	1.04
	0.5		0.89		0.94
	1.5		0.68		0.62
	2.5*		0.55		0.4
V79	0.25	2	1	2	0.99
	0.5		1.19		0.98
	1.5*		1.23		0.67
	2.5*		1.08		0.61
	0.25*	5	0.97	5	0.8
	0.5*		0.88		0.78
	1.5*		0.88		0.63
	2.5*		0.74		0.38

^*P < 0.05 between X-ray + cisplatin and proton + cisplatin.