Tan Fang, Mosunjac Marina, Adams Amy L, Adade Beverly, Taye Oleyad, Hu Yijuan, Rizzo Monica, Ofori-Acquah Solomon F
Aflac Cancer Center and Blood Disorders Service, Department of Pediatrics, Emory University School of Medicine, 2015 Uppergate Drive, Atlanta, GA 30322, USA.
BMC Cancer. 2014 Sep 25;14:715. doi: 10.1186/1471-2407-14-715.
Variation in tumor biology in African-American (AA) and Caucasian (CAU) women with breast cancer is poorly defined. Activated leukocyte cell adhesion molecule (ALCAM) is a bad prognostic factor of breast cancer yet it has never being studied in the AA population. We tested the hypothesis that ALCAM expression would be markedly lower in cases of AA breast cancer when compared to CAU.
Cases of breast cancer among AA (n = 78) and CAU (n = 95) women were studied. Immunohistochemical staining was used to semi-quantitatively score ALCAM expression in tumor and adjacent non-tumor breast tissues. Clinico-pathological characteristics including histological type, histological grade, tumor size, lymph node metastasis, estrogen receptor (ER), progesterone receptor (PR), and HER2-neu status were abstracted, and their association with ALCAM expression tested.
Univariate analysis revealed that the level of ALCAM expression at intercellular junctions of primary tumors correlates with histological grade (AA; p = 0.04, CUA; p = 0.02), ER status (AA; p = 0.0004, CAU; p = 0.0015), PR status (AA; p = 0.002, CUA p = 0.034) and triple-negative tumor status (AA; p = 0.0002, CAU; p = 0.0006,) in both ethnic groups. Multivariate analysis demonstrated that ethnicity contribute significantly to ALCAM expression after accounting for basal-like subtype, age, histological grade, tumor size, and lymph node status. Compared to CAU tumors, the AA are 4 times more likely to have low ALCAM expression (p = 0.003).
Markedly low expression of ALCAM at sites of cell-cell contact in primary breast cancer tumors regardless of differentiation, size and lymph node involvement may contribute to the more aggressive phenotype of breast cancer among AA women.
非裔美国（AA）和白种（CAU）乳腺癌女性的肿瘤生物学差异尚不明确。活化白细胞细胞黏附分子（ALCAM）是乳腺癌的不良预后因素，但从未在非裔美国人群中进行过研究。我们检验了这样一个假设，即与白种人相比，非裔美国乳腺癌患者中ALCAM的表达会显著降低。
研究了非裔美国（n = 78）和白种（n = 95）女性中的乳腺癌病例。采用免疫组织化学染色对肿瘤及相邻非肿瘤乳腺组织中ALCAM的表达进行半定量评分。提取临床病理特征，包括组织学类型、组织学分级、肿瘤大小、淋巴结转移、雌激素受体（ER）、孕激素受体（PR）和HER2-neu状态，并检测它们与ALCAM表达的相关性。
单因素分析显示，原发性肿瘤细胞间连接处的ALCAM表达水平与两个种族的组织学分级（非裔美国人；p = 0.04，白种人；p = 0.02）、ER状态（非裔美国人；p = 0.0004，白种人；p = 0.0015）、PR状态（非裔美国人；p = 0.002，白种人p = 0.034）和三阴性肿瘤状态（非裔美国人；p = 0.0002，白种人；p = 0.0006）相关。多因素分析表明，在考虑基底样亚型、年龄、组织学分级、肿瘤大小和淋巴结状态后，种族对ALCAM表达有显著影响。与白种人肿瘤相比，非裔美国人肿瘤中ALCAM低表达的可能性高4倍（p = 0.003）。
无论分化程度、大小和淋巴结受累情况如何，原发性乳腺癌肿瘤细胞间接触部位的ALCAM明显低表达可能导致非裔美国女性乳腺癌更具侵袭性的表型。
