Dormant Cells: The Original Cause of Tumor Recurrence and Metastasis

Abstract

Tumor dormancy is one of the stages in tumor development without clinical symptoms. Tumor dormant cells may appear in early stages of tumor development, as well as in micrometastasis and minimal residual disease. The mechanism for the switch of dormant cells between quiescent and proliferative stages is still largely unknown. Potential mechanisms that may account for the transition between dormant tumor cells and proliferative cells include angiogenesis, immune response, cellular factors, and signaling pathways. The clinical and therapeutic importance of dormant cells requires further studies to provide therapeutic strategies for inhibition of metastasis and tumor recurrence.

Intratumor Heterogeneity and Therapy Resistance: Contributions of Dormancy, Apoptosis Reversal (Anastasis) and Cell Fusion to Disease Recurrence

“…Of the many types of cancer cell misbehavior, dormancy, a type of active sleep, presents a major obstacle in the medical treatment of malignant solid tumors [19][20][21][22]. A subset of dormant cells are considered "giants" and contain either multiple nuclei or a highly enlarged nucleus (sometimes >100 fold) when compared to the nucleus of the bulk of cancer cells within the same tumor [23][24][25][26][27][28][29][30].…”

Radiation resistance: Cancer stem cells (CSCs) and their enigmatic pro-survival signaling

“…Proliferation of these dormant cells can be initiated by changes in the microenvironment (hypoxia, metabolic stress, changed angiogenesis, immune response, etc.) [64]. Previously dormant cells give rise to an increased number of CSCs in cell culture [31] (Fig.…”

Activation of latent metastases in the lung after resection of a metastatic lymph node in a lymph node metastasis mouse model

“…Tumor latency is one stage of tumor development that lacks clinical symptoms [12]. Two mechanisms have been implicated; one involves antagonizing the expansion of a population of dividing tumor cells (tumor mass latency), and the other involves the arrest of tumor cell growth (tumor cell latency or cellular latency) [13].…”