Role of Simian Vacuolating Virus-40 (SV-40) in Causing Cancer/Tumors

The Simian vacuolating virus-40 (SV-40) is a polyoma virus. The SV-40 is a DNA virus that has the potential to cause tumors. Simian vacuolating virus-40 is believed to slash/suppress the transcriptional properties of tumor-suppressing p53 gene in human beings through its large T-antigen (SV-40 large T-antigen) as well as small T-antigen (SV-40 small T-antigen). It has been genetically established that SV-40 large T-antigen is the major protein involved in neoplastic process. The SV-40 large T-antigen predominantly exerts its effect through deregulation of tumor-suppressing p53 gene, which is responsible for initiating regulated cell death (apoptosis). The regulated cell death or apoptosis is a natural phenomenon that is must for maintaining shape and size of our body organs and tissues. The p53 gene is the most often mutated gene in human cancers. Due to its tumor suppressor role the p53 gene is invariably called the guardian of human genome. The p53 protein present in the cells, plays a major role in the regulation of normal cell cycle, differentiation of cells and cell death. The p53 gene also takes care of DNA repair, aging process and formation of blood vessels. It provides switching mechanism for activation and deactivation of transcription of its target genes by binding to the corresponding DNA sequences in the nuclei of cells. The cell cycle is arrested normally when a cell is damaged. Mutations caused by SV-40 virus in p53 gene would contribute to uncontrolled cellular proliferation, leading to a tumor. It has very well been reported in the medical literature that SV-40 is associated with brain tumors, malignant mesothelioma, non-Hodgkin lymphoma and bone cancers.


Immunohistochemical (IHC) testing is required to detect and demonstrate the viral infection in tumor tissue/biopsy. The immunohistochemical detection of simian vacuolating virus-40 (SV-40) could be culminated, using anti-simian vacuolating virus-40 (anti-SV-40) antibodies. The IHC testing on formalin fixed, paraffin embedded tissues has an advantage over immunofluorescence testing that one would have the convenience of archiving IHC stained slides for future reference. The worldwide availability of anti-simian vacuolating virus-40 (anti-SV-40) antibodies has given a boost to the research in this field.

Carcinomas & Role of Diagnostic Pathology

The word carcinoma is synonym for cancer or malignancy in medical science. Carcinomas may develop from a variety of epithelial tissues of various sites of human body. Epithelial tissues (layers of body cells lining the wall) of respiratory tract, gastrointestinal tract (GI tract) reproductive tract (vagina, cervix, uterus and fallopian tubes), oral cavity, head & neck, breast and skin may transform as carcinoma due to viral infections, genetic mutations and/or biochemical changes in our body. The histopathological diagnosis based on varied morphology of cells and their nuclei is very challenging for the pathologists. For the accurate differential diagnosis of carcinomas found in the primary organs and at metastatic sites in the biopsy materials/specimens, pathologists have to depend on advanced techniques/methodologies like immonohistochemistry (IHC), in-situ hybridization, molecular genetics, microarray etc.


A variety of panels of tumor specific & cells’ phenotype specific primary antibodies have been chalked-out through worldwide deliberations for accurate diagnosis of carcinomas/malignancies with reference to established literature and WHO classifications of carcinomas/malignancies. An accurate diagnosis provides the direction for the line of treatment or surgical interventions. However, individual results of advanced investigations may vary somewhat within diagnostic centers, probably due to protocols followed. The storage conditions and exhausted lifespan of primary antibodies used for IHC may influence the outcome of final result, so there is need for strict quality assurance at pathological diagnostic centers.