Table 2.

Absolute ABCB1, ABCG2 and ATPase levels in plasma membrane fractions of surgically removed tumor tissue determined with quantitatively targeted absolute proteomics

	Total protein used for digestion (μg) (n)	ABCB1 (fmol/μg) (CV%)	ABCG2 (fmol/μg) (CV%)	ATPase (fmol/μg) (CV%)
p01	50 (1)	0.97 (<5%)	1.53 (<5%)	178.3 (<5%)
p02	50 (4)	0.79 (2.7 %)	0.85 (4.4 %)	257.1 (0.6%)
p03a	25 (1)	0.69 (<5%)	0.94 (<5%)	60.1 (<5%)
p03a	50 (3)	0.94 (6.4 %)	1.4 (8.2 %)	164.6 (7.1 %)
p05	40 (1)	0.64 (<5%)	1.10 (<5%)	83.3 (<5%)

For lower limits of quantification, see [27]

%CV, % coefficient of variation: n = digestion replicate, each digested sample was injected three times. Quantification CV% <5% is the variation between transitions and results from three injections (for the three samples digested once and injected three times)

^aTwo different samples collected during surgery