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Tumor Discovery RNA-protein complexes deregulated in cancer

nucleolus and various ribonucleoprotein (RNP) granules, epigenetically and epitranscriptome regulation relevant to
such as promyelocytic leukemia (PML) nuclear bodies, the field of cancer cell biology.
speckles, paraspeckles, Cajal bodies, DNA damage foci,
and processing (P) bodies. In contrast, U bodies, stress 2. BC localization and
granules (SGs), signalosomes, and the pyrenoid are compartmentalization
found outside the nucleus. A single protein capable of There are five mechanisms of messenger RNA (mRNA)
simultaneously interacting with multiple copies of itself localization: (1) diffusion and local entrapment,
drives homotypic phase separation, whereas interaction (2) stabilization and controlled degradation, (3) active
with multiple other biomolecules leads to heterotypic phase
separation, as observed in RNA–protein complexes. transport by molecular motors, (4) vesicular trafficking
1,2
13-17
Figure 1 illustrates a schematic of various MLOs and their through endosomes, and (5) integration into BCs. A
cellular localization. In heterotypic phase separation, a RNP particle undergoes various transitions throughout
molecule interacts with various biomolecules to aggregate its lifetime; it leaves transcription sites, reaches nuclear
and undergo liquid–liquid phase separation (LLPS). The speckles for splicing, moves into the cytoplasm through the
structure of RNA and similar polymers, such as poly- nuclear pore, and appears in the cytoplasmic granules of
ADP ribose (PAR), plays a pivotal role in determining specific cells. These granules include transport granules, P
3,11
the dense-phase identity within condensates. RNA bodies for degradation, and SGs under stress conditions.
3,4
involvement in condensate formation near enhancers or Collectively, these miniature LLPS structures are referred
promoters suggests regulatory roles of noncoding RNAs to as BCs. 12-14 Localized condensates consist of components
(ncRNAs). BCs are various, and this review discusses Bcs that anchor the structure to specific functional cellular
formed by ncRNAS and proteins. 3,5 locations. For instance, in nuclei, proteins may bind to
specific DNA or RNA sequences to form BCs, whereas in
The role of RNA in condensates holds therapeutic the cytoplasm, BCs are often located near the membrane. 15,16
potential, enabling innovative applications such as active
ribozymes. The role of altered phase separation, oncogenic Compartmentalization is a critical determinant in
RNAs, and BC-forming proteins in cancer is well achieving high local concentrations of biomolecules and
established. 6-13 Targeting condensates in cancer therapy their substrates while excluding functionally irrelevant
aims to address condensatopathies, impair aberrant molecules. 17-19 Another contributing factor is transcriptional
formation, inhibit target functions, and deliver drugs. bursting, during which a BC located in the promoter
This review focuses on the significance of BC formation, region of a gene can recruit RNA polymerase molecules. 20,21
oncogenic RNAs, and RNAs, modified epigenetically or Over short time frames, condensates can rapidly form

Figure 1. Occurrence of different biomolecular condensates inside the nucleus (promyelocytic leukemia nuclear bodies, paraspeckles, and Cajal bodies)
and outside the nucleus (stress granules, P bodies, and U bodies). As an example, an RNA–protein complex representing a paraspeckle is marked outside
the cell. Image created by the authors

Volume 3 Issue 4 (2024) 2 doi: 10.36922/td.4657