title: The impact of cyclin D1 overexpression on the prognosis of ER-positive breast cancers: a meta-analysis.
abstract: Cyclin D1 (CCND1), a key regulator of cell cycle progression, is overexpressed in many human cancers, including breast cancer. However, the impact of CCND1 overexpression in these cancers remains unclear and controversial. We conducted a systematic literature search in PubMed and EMBASE with the search terms "cyclin D1", "CCND1", "breast cancer", "prognosis", and potential studies for analysis were selected. Studies with survival data, including progression-free survival (PFS), overall survival (OS) or metastasis-free survival (MFS), were included in this meta-analysis. A total of 33 studies containing 8,537 cases were included. The combined hazard risk (HR) and its 95 % confidence interval (CI) of OS, PFS and MFS were 1.13 (95 % CI 0.87-1.47; P = 0.35), 1.25 (95 % CI 0.95-1.64; P = 0.12), and 1.04 (95 % CI 0.80-1.36; P = 0.76), respectively, for primary breast cancer patients with tumors exhibiting CCND1 overexpression. Interestingly, the impact of CCND1 expression on OS was a 1.67-fold (95 % CI 1.38-2.02; P = 0.00) increased risk for ER-positive breast cancer patients. However, CCND1 overexpression exhibited no association with the PFS or OS of patients who received epirubicin-based neoadjuvant chemotherapy, for which the P values were 0.63 and 0.47, respectively. In summary, CCND1 overexpression impacts the prognosis of ER-positive breast cancer patients, but not patients with unselected primary breast cancer or patients treated with neoadjuvant chemotherapy.
authors.affiliation: Key Laboratory on Diagnosis and Treatment Technology on Thoracic Cancer, Zhejiang Cancer Hospital (Zhejiang Cancer Research Institute), Hangzhou, No. 38 Guangji Road, Banshanqiao District, Hangzhou, 310022, China.
authors.forename: Xiao-Ling
authors.initials: XL
authors.lastname: Xu
authors.forename: Shu-Zheng
authors.initials: SZ
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Wei-Hui
authors.initials: WH
authors.lastname: Zheng
authors.forename: Xiang-Hou
authors.initials: XH
authors.lastname: Xia
authors.forename: Hong-Jian
authors.initials: HJ
authors.lastname: Yang
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Mao
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism / Q000401:mortality*; D019938:Cyclin D1 / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D020360:Neoadjuvant Therapy; D011379:Prognosis; D017594:Publication Bias; D011960:Receptors, Estrogen / Q000378:metabolism
chemical_list: D011960:Receptors, Estrogen; D019938:Cyclin D1