title: C-kit overexpression correlates with KIT gene copy numbers increases in phyllodes tumors of the breast.
abstract: We determined c-kit expression in the stroma and epithelia of benign, borderline, and malignant phyllodes tumors (PTs), respectively, as well as the relationship between c-kit expression in stromal elements and KIT gene copy number variations (CNVs). To assess c-kit expression and KIT CNVs, 348 PT cases were studied: 120 (34.4 %) benign cases, 115 (33.1 %) borderline cases, and 113 (32.5 %) malignant cases. All of these cases were evaluated for c-kit (CD117) expression using immunohistochemistry. Forty-two cases (29 c-kit-positive in the stromal cells cases and 13 negative cases) were investigated for KIT gene CNVs via genomic polymerase chain reaction (PCR). The overall rate of c-kit positivity in the stroma was 46.8 %, as well as 24.2, 53.1, and 64.6 %, respectively, in PTs of three different grades. However, in the majority of cases, the epithelia were c-kit positive (98.2 %), and the positivity was 100, 99.1, and 95 % in PTs of three different grades, respectively. There was a significant change in the expression of c-kit in the stroma and epithelia according to grade (P < 0.001, P = 0.014). From the genomic PCR results, we can confirm that c-kit positivity in the stroma is directly correlated with KIT gene copy numbers increases (P = 0.003, P = 0.041). We demonstrated that c-kit expression in the stroma of PTs is positively associated with malignancy. c-Kit epithelial positivity was inversely correlated with PTs malignancy. c-Kit overexpression in the stroma was related to KIT gene copy numbers increases.
authors.affiliation: Department of Breast Cancer Pathology and Research Laboratory, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, West Huanhu Road, Ti Yuan Bei, Hexi District, Tianjin, 300060, China.
authors.forename: Junjun
authors.initials: J
authors.lastname: Liu
authors.forename: Xiaozhen
authors.initials: X
authors.lastname: Liu
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Feng
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.forename: Shuhua
authors.initials: S
authors.lastname: Lv
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Yun
authors.initials: Y
authors.lastname: Niu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D002648:Child; D056915:DNA Copy Number Variations; D005091:Exons; D005260:Female; D018628:Gene Dosage; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D060787:Neoplasm Grading; D003557:Phyllodes Tumor / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016133:Polymerase Chain Reaction; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics*; D055815:Young Adult
chemical_list: D019009:Proto-Oncogene Proteins c-kit