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Tumor Discovery Cell-cell communication in cancer

4.1. Cell-to-cell communication and metastasis increasing the release of CTCs. By considering metastasis

Metastasis occurs when cancer cells detach from their as a “normal phenomenon” rather than something unique
original site and travel through the bloodstream to establish to cancer, the researchers found that NALCN regulates the
themselves in other organs, such as the lungs, bones, brain, dissemination of both normal and cancerous epithelial
or liver. Metastasis is the leading cause of death from cells, thereby distinguishing the process of metastasis
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cancer. The primary tumor rarely causes death; instead, from cancer. These normal disseminated epithelial-like
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it is the formation of new tumors in distant organs that cells can “metastasize” to distant organs. However, instead
leads to patient mortality. The process of metastasis is of forming tumors, they integrate into normal structures
highly inefficient, requiring cancerous cells to undergo within these tissues, such as kidney tubules. For this
numerous changes to survive their journey and thrive in a process to occur, the seeded circulating epithelial-like stem
new environment. Intercellular communication enhances cells must interact with neighboring cells in their new
this process in various ways. For instance, tumor cells environment to mimic or adapt to a new cell state.
may collaborate with lymphocytes and/or macrophages to 5. Cell communication research is changing
create a pro-tumor environment. Tumor cells sometimes the face of cancer treatment
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migrate together, resembling an island moving through the
bloodstream with its own microenvironment, in search Research has transformed our understanding of cancer
of a new site. These cells alter their communication with and, consequently, our approach to treatment. We now
non-cancerous cells, such as those in the vasculature or know that different parts of a tumor communicate to
immune system, to ensure their survival. This cell editing coordinate growth, and blocking this communication
process generates signals that favor and support the tumor could lead to new treatment strategies. Additionally, tumor
cells rather than normal cells. 29 cells can disguise themselves, tricking the immune system
Migrating tumor cells, known as circulating tumor into perceiving them as “normal” cells. They engage with
cells (CTCs), have been found to have a significantly receptors to mask the tumor, adopting the tissue’s features
higher success rate in forming metastatic tumors when to blend in. This cell-to-cell communication allows tumor
they cluster together—up to 50 times higher. Cell-to- cells to interact with normal cells, enabling their survival.
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cell communication within the CTC cluster helps these Significant efforts and technological advancement are
tumor cells survive the harsh environments they encounter underway to disrupt this masking process and reveal
during metastasis. In the bloodstream, CTCs face strong the true identity of tumor cells (Figure 4). For instance,
physical pressures from flow and constriction, as well as immune checkpoint inhibitors are being used to block the
attacks from immune cells. In distant tissues, the growth masking signals, allowing the immune system to recognize
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environment differs greatly from the original tissues, and inhibit tumor cells.
causing many CTCs to die or cease growing permanently. Several types of immunotherapies are effective in
However, CTCs in a cluster gain protection through cell- treating cancer, including monoclonal antibody therapies
to-cell communication, enabling them to survive in the designed to recognize specific proteins on cancer cells,
bloodstream and successfully regrow in distant organs. mimicking the body’s natural response. These therapies
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Investigators have thereby focused on rapidly testing hijack cell-to-cell communication, allowing drug
patient tumor cells for metastatic potential rather than treatments to be delivered directly into the tumor to kill
growth. This approach allows scientists to determine the disease. Examples include trastuzumab and rituximab,
within a few hours which drugs can most effectively reduce which work in different ways to either kill cancer cells or
the risk of metastasis for the specific cells from a patient’s stop them from growing. Another approach is chimeric
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tumor. 32 antigen receptor T-cell therapy, a type of adoptive cell
The electrical activity of cells has been associated with transfer. This involves harvesting a patient’s immune cells
cancer’s ability to metastasize. Research has shown that and modifying them to recognize and target tumor cells.
prostate cancer cells can modify their baseline voltage A receptor designed to identify a specific protein on the
to open sodium ion channels in their membranes. By cancer cells is added to the immune cells. Once these
opening these channels, cancer cells allow ions to enter, modified cells are administered back to the patient, they
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increasing their likelihood of metastasizing. Conversely, target and kill the tumor.
closing these channels could potentially prevent Future treatments will continue to focus on blocking
metastasis. On the other hand, the loss of function of cell-to-cell communication, and several existing therapies
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the sodium leak channel non-selective protein (NALCN) are already used to treat breast cancer. These include
in gastrointestinal cancers promotes metastatic disease by selective estrogen receptor modulators like tamoxifen and

Volume 4 Issue 2 (2025) 96 doi: 10.36922/td.8323