The Nucleolus in Tumor Pathology

As a consequence of the enhanced ribosome biogenesis and the alteration in the molecular basis, controlling cell proliferation, the morphological and functional alterations in the nucleolus have been broadly observed in tumors. Creative Biolabs has an experienced and professional team, which offers all aspects of ribosomal technologies for researchers to discover the profound mysteries of the nucleolus in tumor pathology.

Fig.1 Histological sections of two human breast carcinomas with larger size of nucleoli in g with worse prognosis. (Montanaro, 2008)

Interaction to Nucleolus and Ribosome

The nucleolus is the organelle of a nucleus which is participating in the biogenesis of ribosomes. Cell proliferation introduced nucleolar hypertrophy is seemed to be intimately associated with nucleolar function, which also regulates the efficiency of ribosome biogenesis. Proto-oncogenes as well as suppressor genes in tumor cells also regulate the biogenesis of ribosomes, the mechanism of which is hence possibly related to the alteration of nucleolar structure and function.

Nucleolus Dysfunction and Cancer

Some statistics suggest that nucleolar dysfunction provokes the production of abnormal ribosomes. The quantitative and qualitative alterations of ribosomes are potentially the cause of cancer pathology. For illustration, nucleolar functional up-regulation might be linked to neoplastic transformation in chronic liver disease from the viral infection, which activates the RNA polymerase I and III (Pol I and III). In addition to nucleolar hypertrophy and up-regulation of the nucleolar function related to tumor pathology, the nucleolar alterations in tumors are also linked to the amount of proliferating tumor cells and proliferation rate of the cycling cells, and kinetics parameters. Alterations of proto-oncogenes and tumor suppressor genes occur frequently in tumor cells, some of which cause nucleolar changes and thus ribosome biogenesis changes.

For example, oncoprotein MYC directly regulates the RNA polymerase I transcriptional activity of nucleolar proteins that are responsible for ribosome biogenesis. It has been found overexpressed in human hematological malignancies and solid tumors. Cyclins D and E are in charge of the transcription of ribosome genes in normal cell cycle progression. They are overexpressed in many human tumors. Furthermore, the degree of nucleolar hypertrophy is directly associated with the intensity of the retinoblastoma tumor suppressor protein pRB and p53 pathway changes. The loss or the functional changes of pRB and p53, could up-regulate the ribosomal biogenesis and affect the structure of the ribosome, which result in an imbalance of protein translation and the genesis of cancer.

Creative Biolabs provides advanced ribosomal technologies to discover the molecular mechanisms of nucleolar alterations that enhance ribosome biogenesis, and thus provoke tumorigenesis. Researchers could utilize our professional services to digger the nucleolus-related causes of the formation of cancer and novel cancer treatments.

To get access to our ribosome-related services, please check out the following links:

• Ribosome Separation and Extraction Services
• Ribosome Analysis Services
• Ribosome Marker Antibody Development Services

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Reference

1. Montanaro, L.; et al. Nucleolus, ribosomes, and cancer. The American journal of pathology. 2008, 173(2): 301-310.