Table 1.

TrxR inhibitors as radiosensitizers in different cancers.

Sr. No.	Compound(s)	Mechanism	In vitro (effective concentration)	Cancer Type /Cell line	Ref.
			In vivo (effective dose)
1.	Auranofin	Interaction of gold (soft acid) with catalytic SeC (soft base) of TrxR	3–10 μM; 0.05 and 0.25 μM	Murine mammary carcinoma (4T1, EMT6); human breast cancer (MDA-MB-231 and SUM159)	[31]
			Balb/c mice 3mg/kg/day subcutaneous for 10 days	4T1 / EMT6 tumor bearing mice
	Gold nanoparticles	Interaction of gold (soft acid) with catalytic SeC (soft base) of TrxR	8.22 nM	NSCLC (A549)	[28]
2.	[Au(SCN)(PEt3)]	i. Isothiocyanate mediated reversible TrxR inhibition	2.5 μM	NSCLC (U1810)	[29]
		ii. Au(I)-selenol interaction mediated TrxR inhibition
3.	Selenium containing i. BBSKE	Reversible inhibition of TrxR	5 μM	NSCLC (A549, H1299)	[9]
			C57 mice (36 mg/kg/day oral for 14 days)	Lewis Lung Carcinoma (LLC) tumor bearing mice
	ii. Se-D3	Reversible inhibition of TrxR	4–10 μg/ml	Melanoma (A375)	[37]
4.	i. Curcumin	Michael addition to TrxR and conversion into ROS generating enzyme	30–100 µM	Breast (MCF7 2D monolayer and 3D spheroid)	[33]
			10 µM	Squamous carcinoma (HeLa & FaDu)	[40]
			10 µM	HNSCC (FaDu, JHU022, SQ20B)	[10]
			Diet enriched with 1% w/v curcumin beginning on day 7 after tumor transplant (2Gy x 3)	FaDu-CMV-Luciferase cells in to athymic nude mice
	ii. dimethoxy-curcumin		3.1 µM	NSCLC (A549)	[26]
5.	Piperlongumine	Michael addition to Cys498 and hydrogen bond formation with Cys-497, Gln-494 and Trp-407	15 μM	Colorectal cancer (CT26)	[15]
			10 μM	Colorectal cancer DLD-1
6.	Indolequinone (IQ9)	Alkylation of SeC498 of TrxR	565.0 ± 29.5 nM	Brest cancer (MDA-MB-231)	[14]
			501.6 ± 170.7 nM	Breast cancer (MDA-MB-468)
			194.6 ± 4.5 nM	Breast cancer (MDA-MB-436)