Gene expression profiling of prostate tissues and seminal vesicles from PB-Pten-NICD mice

To investigate the identity of the tissue origin for metastases, we compared gene expression profiles of the prostate tissues and seminal vesicles from PB-Pten-NICD mice and those of 7 lung metastases from different mice. Three respective cell lines established from primary seminal vesicle tumors, primary prostate tumors, and lung metastases in PB-Pten-NICD mice were also included in the microarray analysis. We hypothesized that the gene expression profiles of primary and metastatic tumors should resemble those of their tissue origins. We identified genes differentially expressed between the seminal vesicle and prostate tumors. The expression profiles of the two cell lines established from primary tumors resembled those of their respective tissue origins, which supports our hypothesis. The expression profile of the metastatic cell line resembled those of the prostate tumor tissues, indicating the prostate as its tissue of origin. The expression profiles of 2 metastatic specimens each resembled those of the seminal vesicle tumors and the prostate tumors, respectively, while the expression profiles of the remaining 3 samples displayed a mixed pattern. This study suggests that metastatic tumors in this model may have originated from either the prostate, or the seminal vesicles, or both. Gene expression microarray analyses were performed on prostate tissues and seminal vesicles (SVs) from PB-Pten-NICD mice, on lung metastases from different mice, and on three respective cell lines established from primary seminal vesicle tumors, primary prostate tumors, and lung metastases in PB-Pten-NICD mice.

为探究转移瘤的组织起源，我们对比了PB-Pten-NICD小鼠的前列腺组织与精囊（seminal vesicles, SV）的基因表达谱，以及7份来自不同小鼠的肺转移灶的基因表达谱；同时将三株分别源自PB-Pten-NICD小鼠原发性精囊瘤、原发性前列腺瘤及肺转移瘤的细胞系纳入基因表达微阵列分析。我们提出假说：原发瘤与转移瘤的基因表达谱应与其组织起源的表达谱高度相似。本研究鉴定出精囊瘤与前列腺瘤之间存在差异表达的基因，其中两株原发瘤来源细胞系的表达谱与其对应组织起源的表达谱一致，验证了前述假说；转移瘤细胞系的表达谱与前列腺瘤组织的表达谱相似，提示该转移瘤的组织起源为前列腺。另有2份转移标本的表达谱分别与精囊瘤、前列腺瘤的表达谱相似，而剩余3份样本的表达谱则呈现混合模式。本研究表明，该模型中的转移瘤可起源于前列腺、精囊，或两者兼有。本研究针对PB-Pten-NICD小鼠的前列腺组织与精囊、不同小鼠的肺转移灶，以及三株分别源自PB-Pten-NICD小鼠原发性精囊瘤、原发性前列腺瘤及肺转移瘤的细胞系，开展了基因表达微阵列分析。