title: RACK1: A superior independent predictor for poor clinical outcome in breast cancer.
abstract: We aimed to investigate the expression of RACK1 in breast cancer, evaluate its role in predicting prognosis and compare with commonly used biomarkers: Ki67, ER, PR and HER-2 for patients with breast cancer. The RACK1 expression and its clinical significance were examined in 160 breast carcinoma patients using immunohistochemistry. Correlations of RACK1 expression with other commonly used biomarkers and survival analyses were assessed. Immunohistochemistry results showed that the number of RACK1 cases scoring 0, 1, and 2 were 66, 54, and 40, respectively. RACK1 staining was strongly related to clinical stage, histological grade, Ki67, ER, PR and HER-2 (all p < 0.05). Consistently, all of the cases exhibiting RACK1 staining score 0 were survivors, whereas the majority (55.0%) of those exhibiting RACK1 staining score 2 were deaths. Kaplan-Meier survival analysis of 160 cases revealed a correlation between higher RACK1 expression levels and shorter overall survival times (p < 0.001). Univariate and multivariate analyses revealed that RACK1, tumor size, lymph node metastasis, and HER-2 were independent prognostic factors (all p < 0.05). Interestingly, receiver operator characteristic (ROC) curves showed that the ROC areas for RACK1, Ki67, ER, PR and HER-2 were 0.833, 0.766, 0.446, 0.387, and 0.689, respectively, and the superiority of RACK1 in sensitivity and specificity as biomarker was demonstrated. To our knowledge, it is the first time to investigate the expression of RACK1, and identified that RACK1 is a superior independent biomarker for diagnosis and prognosis comparing with currently widely used diagnostic index in breast carcinoma.
authors.affiliation: Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Xi-Xi
authors.initials: XX
authors.lastname: Cao
authors.forename: Jing-Da
authors.initials: JD
authors.lastname: Xu
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Liu
authors.forename: Jia-Wen
authors.initials: JW
authors.lastname: Xu
authors.forename: Wen-Juan
authors.initials: WJ
authors.lastname: Wang
authors.forename: Qing-Quan
authors.initials: QQ
authors.lastname: Li
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.forename: Zu-De
authors.initials: ZD
authors.lastname: Xu
authors.forename: Xiu-Ping
authors.initials: XP
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D009367:Neoplasm Staging; D012372:ROC Curve; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D019204:GTP-Binding Proteins; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C419368:RACK1 protein, human; C508053:ERBB2 protein, human