Sirchia Rosalia, Luparello Claudio
Dipartimento di Biologia Cellulare e dello Sviluppo, Università di Palermo, Palermo, Italy.
Biol Chem. 2007 May;388(5):457-65. doi: 10.1515/BC.2007.059.
We have previously shown that PTHrP(38-94) amide restrains growth and invasion in vitro, causes striking toxicity and accelerates death of some breast cancer cell lines, the most responsive being MDA-MB231, for which tumorigenesis was also attenuated in vivo. We have also demonstrated that mid-region PTHrP gains access to the nuclear compartment of these cells and displays DNA-binding properties in vitro by recognizing targets in both cellular chromatin and isolated oligonucleotides. Here, we examined whether PTHrP(38-94) amide was able to modulate gene expression of MDA-MB231 cells, employing a combination of conventional, differential display and semi-quantitative multiplex PCR techniques. The results obtained provide first evidence that PTHrP(38-94) amide can affect gene expression in tumor cells, identifying A4-differentiation protein/PLP2 as up-regulated, and HOX7/MSX1, COX6C, FZD6, OXR1 and TMCO4 as down-regulated genes in treated cells, and suggest that the cytotoxic activity of the peptide can be ascribed, at least in part, to such transcriptional reprogramming.
我们之前已经表明，甲状旁腺激素相关蛋白（PTHrP）（38 - 94）酰胺在体外可抑制生长和侵袭，具有显著的毒性，并加速某些乳腺癌细胞系的死亡，其中反应最明显的是MDA - MB231细胞系，其体内肿瘤发生也受到抑制。我们还证明，中段PTHrP能够进入这些细胞的核区室，并通过识别细胞染色质和分离的寡核苷酸中的靶标在体外显示出DNA结合特性。在此，我们采用传统的差异显示和半定量多重PCR技术相结合的方法，研究了PTHrP（38 - 94）酰胺是否能够调节MDA - MB231细胞的基因表达。获得的结果首次证明PTHrP（38 - 94）酰胺可影响肿瘤细胞中的基因表达，鉴定出A4 - 分化蛋白/PLP2为上调基因，而HOX7/MSX1、COX6C、FZD6、OXR1和TMCO4为处理细胞中的下调基因，并表明该肽的细胞毒性活性至少部分可归因于这种转录重编程。
