Tumor diagnosis based on nucleolus labeling

The nucleolus is crucial for ribonucleoprotein particle assembly. Vital molecular regulators such as RB (retinoblastoma protein) and p53 (tumor suppressor protein) influence nucleolar function and tumorigenesis. The absence or inactivation of these proteins often leads to nucleolar dysfunction and alteration, which is a key indicator among the primary histopathological features of malignancy. These changes are closely related to the proliferation, differentiation, and survival of tumor cells, such as abnormalities in the number, size, and shape of nucleoli. In recent years, as the relationship between nucleoli and tumorigenesis has been further explored, various nucleolar labeling techniques have been developed for pathological analysis and tumor diagnosis, such as immunohistochemistry (IHC)/immunofluorescence (IF), and fluorescence labeling. These methods complement the traditional use of transmission electron microscopy (TEM) for observing nucleoli. In this review, we explore the relationship between the nucleolus and tumorigenesis and evaluate current methods for diagnosing tumors by examining nucleolar characteristics. We discuss the advantages, disadvantages, and applications of diagnostic techniques such as TEM, IHC/IF, and fluorescence labeling for analyzing the nucleolus.