Table 2.

The median values of proteasome ChT-L activity and proteasome concentration in plasma of patients with MM treated with bortezomib or CTD

No. of patients		Parameters
		Proteasome ChT-L activity (U/mg)			Proteasome concentration (μg/ml)
		Baseline	After third cycle	End of treatment	Baseline	After third cycle	End of treatment
Bortezomib	All patients (n = 52)	1.24 (0.22–3.55)	0.93* (0.27–5.68)	0.87** (0.22-3.65)	2.48 (0.65–11.79)	2.12 (0.53–7.15)	1.79** (0.47–4.26)
	Responders (n = 35)	1.52 (0.35–3.55)	0.81* (0.27–2.08)	0.69** (0.22–1.73)	2.81 (0.79–11.79)	2.05* (0.53–5.3)	1.6** (0.47–3.9)
	Non-responders (n = 17)	0.66 (0.22–1.79)	1.19 (0.29–5.68)	1.24** (0.49–3.65)	1.79 (0.65–4.29)	2.27 (0.58–7.15)	2.19 (0.92–4.26
CTD	All patients (n = 36)	1.15 (0.23–1.73)	0.82 (0.32–1.81)	0.88 (0.27–4.03)	1.72 (0.54–5.05)	1.99 (0.7–4.74)	2.01 (0.79–7.31)
	Responders (n = 18)	0.99 (0.36–1.73)	0.78* (0.32–1.81)	0.99** (0.27–4.03)	1.93 (0.62–5.05)	2.09 (0.9–4.74)	1.83 (0.79–3.15)
	Non-responders (n = 8)	0.62 (0.23–1.42)	0.7 (0.38–0.98)	0.88 (0.53–2.03	1.25 (0.54–2.64)	1.77 (0.7–3.6)	2.04 (1–7.31)

The values are presented as median (range). Responders are patients, who received at least partial response; non-responders are patients with stable and progressive disease

ChT-L chymotrypsin-like, CTD cyclophosphamide, thalidomide, dexamethasone

*p < 0.05 between baseline value and after third cycle

**p < 0.05 between baseline value and end of treatment