Fig. 4

Basal expression of ASS1, BCT-100-induced arginine depletion and localization of BCT-100 in xenograft models. a ASS1 was highly expressed in H226 xenograft but relatively low in 211H xenograft. BCT-100 decreased serum arginine concentration in (b)(i) 211H and (b)(ii) H226 xenograft models. BCT-100 reduced intratumoral arginine level in a dose-dependent fashion in (b)(iii) 211H and (b)(iv) H226 xenografts. Intratumoral level of PEG-BCT-100 was increased in BCT-100 treatment arms with a dose-dependent manner in (c)(i) 211H and (c)(ii) H226 xenografts. BCT-100 was mostly located in the central part of tumor in (d)(i) 211H and (d)(ii) H226 xenografts, with cytosolic compartmentalization ((e)(i), (e)(ii)) as shown by immunoflorescence staining (pictures taken with 400X magnification)