A dormancy mechanism limits metastasis of early spreading cancer cells

Research briefing
A dormancy
mechanism
limits
metastasis of
early
spreading
cancer cells
Mesenchymal-like and
pluripotency-like programs
coordinate the dissemination
and long-lived dormancy of early
breast cancer cells. The
transcription factor ZFP281
controls these programs,
preventing the acquisition of an
epithelial-like proliferative
phenotype and serving as a
previously unrecognized barrier
to metastasis.
This is a summary of:
Aguirre-Ghiso, J. A. et al. ZFP281 drives a
mesenchymal-like dormancy program in
early disseminated breast cancer cells that
prevents metastatic outgrowth in the lung.
Nat. Cancer https://doi.org/10.1038/s43018022-00424-8 (2022).
Published online:
14 September 2022
Publisher’s note
Springer Nature remains neutral with regard
to jurisdictional claims in published maps
and institutional affiliations.
The question
Cancer cells had long been believed to disseminate and metastasize only during late
stages of cancer evolution. However, using
genetic lineage trees, we have previously
shown that disseminated cancer cells (DCCs)
can start to colonize organs very early in cancer evolution. Early DCCs can remain dormant for long periods before forming overt
metastases, sometimes without progressing
through a primary tumor growth state, in
parallel progression to the original primary
tumor1. It is unclear whether this pause in
progression is due to a slow evolution of
early DCCs or to a mechanism that actively
holds early DCCs in a dormant state before
they proliferate and further evolve genetically. Understanding these mechanisms
may enable the maintenance of early DCCs
in this dormant state or selectively killing
them before they metastasize. As early DCCs
differ phenotypically from DCCs that are
derived from late evolved primary tumors,
this knowledge may afford therapeutic
strategies that better target all potential
metastasis-initiating cells.
The discovery
Early DCCs have not been isolated and
molecularly and phenotypically characterized in depth1,2. We used mouse models and
single-cell RNA sequencing to reveal the
heterogeneity and plasticity of breast cancer
DCCs that spread to the lungs across the
evolution of mammary cancer. We found
that early DCCs have very heterogeneous
transcription programs, acquire different
mesenchymal-like (M-like) phenotypes and
express dormancy signatures in vivo. The
M-like programs in different DCC clusters
seemed to be driven by transcription factors
such as those encoded by Neurod1, Sox9,
Prrx1, Snai2 and Twist1, among others. Using
epigenetic analysis and gain-of-function or
loss-of-function assays, we further found
that the transcription factor zinc finger
protein 281 (Zfp281, encoded by ZNF281 in
humans)3, which regulates primed pluripotency, is a key regulator of early DCC spread
and dormancy. During primed pluripotency
in the blastocyst, Zfp281 represses Nanog
while enabling expression and function of
Sox2 and Oct4 (also known as Pou5f1). In
early cancer cells, Zfp281 drives the epithelial–mesenchymal transition (EMT) that
enables dissemination. Accordingly, M-like
clusters of DCCs were enriched for Oct4 and
Sox2 target genes, whereas DCCs clusters
acquiring more epithelial-like features and,
therefore, beginning proliferation, showed
enrichment for genes controlled by Nanog
and Klf4.
Nature Cancer | VOL 3 | October 2022 | 1147–1148 | www.nature.com/natcancer
Zfp281 is induced by fibroblast growth
factor 2 (Fgf2) and twist-related protein 1
(Twist1), suppresses proliferation in the
primary tumor in the mammary fat pad and
induces efficient dissemination to target
organs. After dissemination, Zfp281 expression is maintained and holds early DCCs in a
prolonged dormant, non-proliferative state
via the induction of the class II cadherin 11
(encoded by Cdh11). We demonstrated that
even aggressive primary tumor cells, with
low or no Zfp281 expression, can be reprogrammed into dormancy and prevented
from metastasizing by regaining Zfp281
(Fig. 1) or Cdh11 expression. Thus, Zfp281
regulates a dormancy program in early DCCs
that precedes a slow proliferation phase
towards metastasis and must be overridden
for metastasis outgrowth.
The implications
This mechanism of DCCs dormancy goes
beyond the classical view of the metastatic
cascade. Our findings contribute to an improved understanding of breast cancer early
dissemination and dormancy, and may also
be expanded and tested in other cancers,
especially those in which early spread has
been proposed4.
More work is needed to validate ZFP281
and the M-like dormancy program in human
DCCs. However, detection of ZFP281 may
help to measure the abundance of early DCCs
in patients and the proclivity of these cells
to develop recurrences. These findings may
also enable the exploitation of these mechanisms to eliminate early dormant DCCs or
force them into an asymptomatic phenotype,
which reduces the chances of metastasis.
Of note, our approach could not fully
distinguish early DCCs from those spreading from late lesions and co-existing in
the lungs. The plasticity of both early and
late DCCs may preclude the identification
of a unique marker to distinguish them.
We also need to understand how hormonal regulation influences this process, as
late recurrence is prevalent in hormone
receptor-positive breast cancer. Additionally, we need to investigate how early
ZFP281+ DCCs interact with late arriving and
more evolved DCCs, which may cooperate
in metastasis initiation5. Finally, whether
early DCCs are the main orchestrators of
the termed pre-metastatic niche5 should be
explored.
Julio A. Aguirre-Ghiso1 and Ana Rita Nobre2
Cancer Dormancy and Tumour Microenvironment Institute, Albert Einstein
College of Medicine, Bronx, NY, USA.
2
Memorial Sloan Kettering Cancer Centre,
New York, NY, USA.
1
1147
“
Expert opinion
The topic is interesting, novel and
with potential clinical relevance.
The most compelling finding is
the linking of EMT (previously known to be
important for dissemination) with dormancy,
References
and the identification of a novel role for
ZFP281, which was not previously implicated
in cancer metastasis.” Neta Erez, Faculty
of Medicine, Tel Aviv University,
Tel Aviv, Israel.
Figure
2. Schardt, J. A. et al. Genomic analysis of
single cytokeratin-positive cells from bone
marrow reveals early mutational events in
breast cancer. Cancer Cell 8, 227–239 (2005).
This paper reveals that early cancer cells
can spread in patients with pathologically
confined breast cancer and hinted to an EMT
as potentially involved in the process.
b
a
DCIS
PT ZFP-OE
PT control
3. Fidalgo, M. et al. Zfp281 functions as a
transcriptional repressor for pluripotency of
mouse embryonic stem cells. Stem Cells 29,
1705–1716 (2011).
This article shows that Zfp281 is a repressor
of Nanog, thereby allowing for differentiation
programs during embryogenesis, and enables
the understanding of Zfp281 function in early
dissemination.
0 µm 25
Fig. 1 | ZFP281 maintains dormancy of early DCCs. a, Human breast ductal carcinoma in situ (DCIS) lesion,
showing early cancer cells positive for nuclear ZFP281 (in green), which indicates that these cells already
have putative dissemination and pro-dormancy potential. Blue indicates DAPI, 4′,6-diamidino2-phenylindole. b, Advanced breast cancer cells expressing human epidermal growth factor receptor 2
(HER2) can efficiently form spontaneous metastasis (dark pink) in mouse lungs (top, control) but can be
programmed into a dormant phenotype with reduced metastatic potential (bottom) when ZFP281
expression and function is restored. OE, overexpression; PT, primary tumor; scale bars, 2 mm. © 2022,
Aguirre-Ghiso, J. A. et al.
Behind the paper
We hypothesized that drivers of early spread
and dormancy had to be already active in
the early lesions. At the beginning of this
study, A.R.N. computationally mined RNA
sequencing data from early lesions and
identified ZFP281 as a transcription factor of
elusive function. Luckily, Jianlong Wang, who
was working at our institution at the time, is
an expert on ZFP281 in embryogenesis, and
we immediately started collaborating. This
specific program was unfunded until very
recently. Large National Institutes of Health
1148
1. Hosseini, H. et al. Early dissemination
seeds metastasis in breast cancer. Nature 540,
552–558 (2016).
This paper reveals that metastasis can be
founded independently of the primary tumor
by early DCCs in a subset of patients with
HER2+ breast cancer.
(NIH) team grants on early dissemination
biology have been hard to obtain despite
requests for applications based on our earlier
work. The most satisfying experiments were
the most uncertain; those for which we
waited ~6 months for metastasis detection.
These results then corroborated the singlecell sequencing data pointing to the fact
that ZFP281 drives the M-like program of
dissemination and dormancy of early DCCs
and can reprogram malignant cells into
dormancy. J.A.A.-G.
4. Klein, C. A. Cancer progression and the
invisible phase of metastatic colonization.
Nat. Rev. Cancer 20, 681–694 (2020).
This review article provides a
wellorchestrated and integrated view of
metastatic progression, with an emphasis on
what may happen during the time residual
cancer persists undetected in patients.
5. Sosa, M. S., Bragado, P. & Aguirre-Ghiso, J.
A. Mechanisms of disseminated cancer cell
dormancy: an awakening field. Nat. Rev. Cancer
14, 611–622 (2014).
This review article provides an integrated
view of the mechanisms that control
cancer cell dormancy across cancers and
how this biology might be linked to early
dissemination, pre-metastatic niche biology,
stem-cell biology and immune regulation of
cancer dormancy.
From the editor
“
By identifying the role of a
key pluripotency factor in
driving M-like gene expression
programs to induce tumor dormancy, this
study highlights the plastic manner in which
aspects of pluripotency, differentiation, EMT
and dormancy are orchestrated during early
tumor cell dissemination.” Editorial Team,
Nature Cancer.
Nature Cancer | VOL 3 | October 2022 | 1147–1148 | www.nature.com/natcancer