Institute of Pathology, Medical University of Graz, Graz, Austria.
Mod Pathol. 2010 Jul;23(7):961-71. doi: 10.1038/modpathol.2010.83. Epub 2010 May 7.
The role of human prolactin and its receptor, the prolactin receptor, in colorectal cancer is largely unknown. Our study aimed to assess the prevalence of prolactin receptor expression, its association with clinicopathological variables, as well as its prognostic value, comparing results of primary tissues with those of corresponding metastases. In all, 373 primary colorectal cancer and 171 corresponding metastases were evaluated for prolactin receptor expression by immunohistochemistry using a tissue microarray technique. Immunoreactivity was semiquantitatively scored as either focal (<10% of tumor cells positive), moderate (10-50%), or extensive (>50%). Prolactin receptor expression was related to clinicopathological parameters as well as patient outcome. To substantiate our findings, prolactin receptor expression was additionally assessed in HT-29 and SW-480 colorectal cancer cell lines using western blot. Prolactin receptor expression was observed in 360 out of 373 (97%) primary tumors, with 21 (6%) cases showing focal, 55 (15%) moderate, and 284 (76%) extensive expression, respectively. Extensive prolactin receptor expression was significantly associated with tumor size (P=0.002) and grade (P<0.001) as well as histological subtype (P<0.001). Somer's D coefficients for concordance of primary tumors with corresponding lymph node and distant metastases were D=0.719 (P<0.001) and D=0.535 (P=0.001), respectively. Extensive prolactin receptor expression was significantly associated with disease progression (P=0.03) and cancer-specific survival (P=0.04) in patients with high-grade cancers. In conclusion, prolactin receptor expression is common in colorectal cancer, with high concordance between primary tumors and corresponding metastases. In view of evolving targeted therapy concepts in colorectal cancer, widespread prolactin receptor expression may offer a therapeutic perspective in affected patients.
催乳素及其受体——催乳素受体在结直肠癌中的作用在很大程度上尚不清楚。我们的研究旨在评估催乳素受体表达的流行率，及其与临床病理变量的相关性，以及比较原发组织和相应转移灶的结果，评估其预后价值。我们使用组织微阵列技术，通过免疫组织化学方法评估了 373 例原发性结直肠癌和 171 例相应转移灶中催乳素受体的表达。免疫反应性通过半定量评分进行评估，分为局灶性（<10%的肿瘤细胞阳性）、中度（10-50%）或广泛（>50%）。催乳素受体表达与临床病理参数以及患者预后相关。为了证实我们的发现，我们还使用 Western blot 评估了 HT-29 和 SW-480 结直肠癌细胞系中的催乳素受体表达。在 373 例原发性肿瘤中，有 360 例（97%）观察到催乳素受体表达，其中 21 例（6%）为局灶性，55 例（15%）为中度，284 例（76%）为广泛表达。广泛的催乳素受体表达与肿瘤大小（P=0.002）和分级（P<0.001）以及组织学亚型（P<0.001）显著相关。原发性肿瘤与相应淋巴结和远处转移灶的 Somer's D 系数分别为 D=0.719（P<0.001）和 D=0.535（P=0.001）。在高级别癌症患者中，广泛的催乳素受体表达与疾病进展（P=0.03）和癌症特异性生存（P=0.04）显著相关。总之，催乳素受体在结直肠癌中表达普遍，原发性肿瘤与相应转移灶之间具有高度一致性。鉴于结直肠癌中靶向治疗概念的不断发展，催乳素受体的广泛表达可能为受影响的患者提供治疗前景。
