P53

Consequently, this means that there is genomic instability, with defects in DNA repair mechanism, transcription and cell cycle checkpoints, which culminates in an increased susceptibility for malignant cell growth (7). Additionally the TP53 gene is a common target of mutations, with 96% of all serous ovarian tumours being characterised by a mutation of this gene (8). The TP53 gene, located on the short arm of chromosome 17 at position 17p13.1, encodes the p53 protein, a sequence-specific transcription factor that plays a major role in tumour suppression. By responding to cell stresses, such as UV-induced DNA damage and hypoxia, p53 can initiate DNA damage repair, cell cycle arrest and apoptosis, preventing tumour formation (9, 10). Unlike BRCA1 mutations, where frameshifts lead to the deletion or non-functionality of the protein, TP53 mutations are typically single-base pair substitutions, with a large proportion being missense mutations, resulting in the loss of function of the wild-type p53. Due to this, cells with mutated p53 proteins will show increased angiogenesis, abnormal growth and proliferation, as well as a resistance to chemotherapy (11, 12). From Figure 1, we can tell that Abbi has type II cancer, as she has a germline BRCA1 mutation which is typically found in type II cancer patients. The development of the primary tumour is due to genetic mutations, however the secondary tumours are as a result of metastasization. There are two methods of metastasis in OC,…

p53, also known as TP53 or tumor protein, is a gene that codes for one protein which stimulates another protein that inhibits enzymes needed to drive the cell cycle and functions as a tumor suppression. It is very important for cells in the role to suppress cancer. P53 has been described as "the guardian of the genome", referring to its role in conserving stability by preventing genome mutation (Strachan and Read, 1999). The name is due to its molecular mass: it is in the 53 kilodalton fraction…

Tumor suppressor gene p53 is among the negative regulators of the cell cycle if affected by alteration, mutations or by interaction with oncogene products of DNA tumor viruses. All these mutations cause genetic changes in the cells and lead to cancer (Levine , Finlay, and Momand, 1991). TP53 plays an important role in tumor prevention, and gene stability and this have been demonstrated…

Hypoxia is a crucial feature of locally advanced solid tumors resulting from a poor oxygen supply delivery owing to excessive cellular proliferation and abnormal vascular architecture. Under these circumstances, cancer cells develop a series of responses in order to adapt to hypoxic conditions. The tumor suppressor p53 has been shown to mediate the cellular response to hypoxia depending on many contexts including cell type, duration and severity of hypoxic exposure. The sphingolipid ceramide,…

Detailed focus question: What is the process of self-renewal and duplication in breast cancer stem cells through E113, the Wnt-beta catenin signaling pathways and the tumor regulator p53? I. Introduction: To explain the cellular and molecular features of my focus question I will provide background on cancer stem cells, some of the various signaling pathways and breast cancer specifically. A. Cancer Stem Cells (Tumor-initiating cells) 1. Basic Features: Have the capacity to self renew and the…

Functions of protein TP53 TP53 has a general name called tumor suppressor protein p53. Tp53 has many names such as phosphoprotein p53, cellular tumor antigen p53, tumor suppressor p53, antigen NY-CO-13, or transformation-related protein 53 (TRP53). Also, TP53 has also been referred to as the guardian of the genome [19]. In 1979, scientists first observed the gene by using SDS-PAGE and found it has a size of about 53-kilodalton (kDa). The location of the TP53 gene is at chromosome 17, at…

The reason for this being that if the animal lives for a long period of time, then the cell will divide more times. If the animal size is large, then they’ll have more cells to divide. These cell divisions bring negative effects to the animal’s health because as cell divides, the chance it will gain a mutation that speeds its growth increases. Therefore, Cells that accumulate several of these mutations may become cancerous. 2) Why might the p53 gene been able to prevent cancer? The p53 gene…

elephants and other mammals, and noted a significant difference in the p53 gene, which codes for a tumor…

which in turn phosphorylates Cdc25A on several residues and target it to proteasomal degradation (Sørensen et al, 2003; Busino et al, 2004). Thus in the absence of active Cdc25A phosphatase, Cdk2 cyclin kinase (Cyclin E/A) stays active and thereby prevents the assembly of pre replication complexes on to the DNA (Mailand et al, 2000; Falck et al, 2001). This branch of the G1/S checkpoint functions independent of p53 and rapidly inhibits cell cycle progression. Under normal conditions,…

Grade IV astrocytomas are two types i.e Primary and secondary tumors , as we know that primary tumors are very aggressive and the most common form of astrocytoma grade IV [19] and the secondary tumors are those which originate as a lower-grade tumor and evolve into a grade IV tumor. It is distinguished histopathologically from diffuse lower-grade astrocytomas by the presence of necrosis or micro vascular proli-feration[20].Among several tumor suppressor genes, p53 reveal to play a key role…