Immortalization-associated gene signature in breast cancer

Excerpt

Cell immortalization has been considered a hallmark of malignancy, yet the molecular signature identifying a tumor's ability to immortalize is not known. To better understand the immortalization process, we used in vitro model systems developed from clinical primary breast cancer specimens. While spontaneous immortalization of tumor cells in vitro is a rare event, immortalization can be achieved through the introduction of the hTERT component of telomerase. Because spontaneously arising cancer cell lines are already immortal and display high levels of telomerase expression, they are not amenable for study of the immortalization process in malignancy. However, finite life primary tumor cultures show low hTERT expression, providing a tool to study the effect of exogenously introduced hTERT. …