1. Volume 127, Issue 1, Pages 294-299 (July 2004)
A new mutation in the KIT ATP pocket causes acquired resistance to imatinib in a gastrointestinal stromal tumor patient 
Elena Tamborini, Lorena Bonadiman, Angela Greco, Veronica Albertini, Tiziana Negri, Alessandro Gronchi, Rossella Bertulli, Maurizio Colecchia, Paolo G. Casali, Marco A. Pierotti, Silvana Pilotti 
Gastroenterology 
Volume 127, Issue 1, Pages (July 2004)
DOI: /j.gastro

2. Figure 1
Morphology and immunocytochemistry of the responsive and nonresponsive lesions. (A and B) H&E staining of the responsive and nonresponsive metastases. (C and D) CD117 immunostaining of the same lesions. In this figure, only the peritoneal responding metastasis is shown because the hepatic one shows superimposable morphology.
Gastroenterology  , DOI: ( /j.gastro )

3. Figure 2
(A) Molecular analysis of the c-Kit gene. Electropherograms of exons 11 and 14 of the responsive and nonresponsive metastases are shown. The nucleotides in black represent the deletion of exon 11. The arrow indicates the point mutation of exon 14 observed only in the nonresponding metastasis. (B) Expression and phosphorylation status of KIT receptor in tumor samples. For each sample, 500 μg of total protein extracts were immunoprecipitated with α-KIT antibodies, run on gel, and blotted with indicated antibodies. In this figure, only the peritoneal responding metastasis is shown because the hepatic one had identical results. C+, NIH3T3 cell line transfected with KIT/Δ559 mutant (carrying the deletion of residue 559) overexpressing a constitutively phosphorylated KIT receptor (positive control); R, responding lesion; NR, nonresponding lesion; C−, normal skin (negative control). Both the mature (145-kilodalton) and partially glycosylated (125-kilodalton) forms of KIT receptor were detected.
Gastroenterology  , DOI: ( /j.gastro )

4. Figure 3
Imatinib mesylate activity on KIT/T670I and Δ559/T670I/KIT mutants. c-Kit mutants were constructed by site-directed mutagenesis using the Promega kit, and an expression vector carrying c-Kit gene (kindly provided by Dr. Yarden) was used as template. The mutant Δ559 was obtained deleting base pair numbers 1696–1698 (GTT) in exon 11 of the wild-type gene; the T670I mutant was obtained substituting the base C 2030 with T in exon 14. (A) COS1 cells were transiently transfected with the c-Kit constructs and incubated with imatinib at the indicated doses for 8 hours. Protein extracts (1 mg) were immunoprecipitated and used for Western blot analysis. Both the mature (145-kilodalton) and partially glycosylated (125-kilodalton) forms of KIT receptor were detected. (B) The same experiment as in A using the KIT/Δ559/T670I mutant. The T670I mutation was introduced into the Δ559/KIT mutant. In this experiment, 800 μg of total protein extracts were immunoprecipitated and used for Western blot analysis. In this experiment, only the mature form of KIT receptor was detected.
Gastroenterology  , DOI: ( /j.gastro )