Figure 4

The cytoplasmic domain of CD98hc is responsible for malignant tumor growth in vivo. Reconstitution of CD98hc omitting shRNA binding was performed utilizing a QuickChange Kit (Stratagene) for the silent mutation (silCD98hc in A); a cytoplasmic truncation mutant was used to interfere with the integrin interaction (TrunSilCD98hc in B) and point mutations in Cys109 and Cys330 interfered with amino acid transporter interaction (poinsilCD98hc in C). Constructs were cloned in pcDNA 3.1 Vector via ECO RI. (ECD: extracellular domain, TMD: transmembrane domain, CPD: cytoplasmic domain). (B) Tumor weight (in mg), highCD98hc/Caki2 tumors, silCD98hcCaki2 tumors, lowCD98hc/Caki2 tumors, trunsilCD98hc/Caki2 tumors, poinsilCD98hc/Caki2 tumors. * p < 0.0001. Data represent means ± S.D. of three mice per group. (C) CD98hc expression was analyzed via immunofluorescence staining of lowCD98hc, highCD98hc, silCD98hc, trunsilCD98hc and poinsilCD98hc Caki2 cell tumor transplants, grown for 8 days after injection into the right flank of nude mice. Upper panel indicate anti CD98hc staining, lower panel indicate anti - PCNA staining.