Disseminated tumor cells (DTCs) frequently spread from breast cancers to the bones, where they may lay dormant for extended periods and evade treatment. How DTCs colonize bone and enter and exit dormancy is not clear. These mechanisms are further complicated by the clinical association of estrogen receptor (ER) status and time to recurrence.
Reporting in the journal Scientific Reports, Rachelle Johnson, PhD, and Miranda Sowder apply flow cytometric and quantitative PCR approaches to detect these rare but significant metastatic DTCs.
They found that ER-positive human breast cancer cells were able to colonize the bone marrow after inoculation in mice regardless of the presence or absence of estradiol, a form of estrogen. In addition, two other cancer cell lines known to lie dormant in the lungs can disseminate to the bone marrow with extended latency periods.
These novel tumor models and detection methods will be instrumental in investigating breast tumor cell homing and latency in the bone, they conclude.
This research was supported in part by grants from the National Institutes of Health (CA194198, CA068485).