Project description:Centrosome amplification induces proliferation arrest and cell invasion. The fate of centrosome amplification cells are studied here.
Project description:Centrosome amplification has long been recognized as a feature of human tumors, however its role in tumorigenesis remains unclear. Centrosome amplification is poorly tolerated by non-transformed cells, and, in the absence of selection, extra centrosomes are spontaneously lost. Thus, the high frequency of centrosome amplification, particularly in more aggressive tumors, raises the possibility that extra centrosomes could, in some contexts, confer advantageous characteristics that promote tumor progression. Using a three-dimensional model system and other approaches to culture human mammary epithelial cells, we find that centrosome amplification triggers cell invasion. This invasive behavior is similar to that induced by overexpression of the breast cancer oncogene ErbB2 and indeed enhances invasiveness triggered by ErbB2. We show that, through increased centrosomal microtubule nucleation, centrosome amplification increases Rac1 activity, which disrupts normal cell-cell adhesion and promotes invasion. These findings demonstrate that centrosome amplification, a structural alteration of the cytoskeleton, can promote features of malignant transformation.
Project description:Centrosome amplification has long been recognized as a feature of human tumors, however its role in tumorigenesis remains unclear. Centrosome amplification is poorly tolerated by non-transformed cells, and, in the absence of selection, extra centrosomes are spontaneously lost. Thus, the high frequency of centrosome amplification, particularly in more aggressive tumors, raises the possibility that extra centrosomes could, in some contexts, confer advantageous characteristics that promote tumor progression. Using a three-dimensional model system and other approaches to culture human mammary epithelial cells, we find that centrosome amplification triggers cell invasion. This invasive behavior is similar to that induced by overexpression of the breast cancer oncogene ErbB2 and indeed enhances invasiveness triggered by ErbB2. We show that, through increased centrosomal microtubule nucleation, centrosome amplification increases Rac1 activity, which disrupts normal cell-cell adhesion and promotes invasion. These findings demonstrate that centrosome amplification, a structural alteration of the cytoskeleton, can promote features of malignant transformation. genome-wide human SNP 6.0 arrays from Affymetrix was used to determine the copy number changes of MCF10A cells with extra centrosomes or depleted of MCAK after grown 4 days in 3-D cultures
Project description:Centrosomal protein 120 (CEP120) is a 120kD centrosome protein that plays an important role in centrosome replication. Overexpression of CEP120 can lead to centrosome amplification, which is closely associated with tumorigenesis and development. However, there are no reports on the relationship between CEP120 and tumors. In our study, overexpression of CEP120 promoted centrosome amplification in gastric cancer (GC), and the role of CEP120 in promoting GC progression was demonstrated in vitro and in vivo. We demonstrated that CEP120 promotes centrosome amplification and GC progression by promoting the expression and centrosome aggregation of the deubiquitinating enzyme USP54, maintaining the stability of PLK4 and reducing its ubiquitination degradation. In conclusion, the CEP120-USP54-PLK4 axis may play an important role in promoting centrosome amplification and GC progression, thus providing a potential therapeutic target for GC.
Project description:We have recently reported that type 2 diabetes promotes cell centrosome amplification via enhancing the expression, biding and centrosome translocation of ROCK1/14-3-3σ complex. In the present functional proteomic study, we further investigated the molecular pathways underlying the centrosome amplification using colon cancer HCT116 cells as experimental model. We found that treatment of cells with high glucose, insulin and palmitic acid triggered the centrosome amplification and increased the expressions of PCNA, NPM and 14-3-3σ. Individual knockdown of PCNA, NPM or 14-3-3σ inhibited the centrosome amplification. Knockdown of PCNA inhibited the treatment-increased expression of ROCK1, while knockdown of ROCK1 did not affect the PCNA expression. High glucose, insulin and palmitic acid also increased the expressions of JNK1 and Stat3, individual knockdown of which up-regulated the treatment-increased expression of 14-3-3σ and promoted the centrosome amplification. In contrast, over-expression of JNK1 inhibited the centrosome amplification. Knockdown of Stat3 enhanced the centrosome translocation of 14-3-3σ. Moreover, we showed that knockdown of JNK1 inhibited the treatment-increased expression of Stat3, but not the other way round. Knockdown of PCNA, JNK or Stat3 did not have an effect on NPM and vice versa. In conclusion, our results suggest that PCNA and JNK1-Stat3 pathways respectively promotes and feedback inhibits the centrosome amplification by targeting at the ROCK1/14-3-3σ complex, and NPM serves as an independent signal for the centrosome amplification.
Project description:Centrosome amplification is a common feature of human tumors, but whether this is a cause or a consequence of human cancer remains unclear. Here, we report the creation of a mouse model in which centrosome number can be persistently increased in the absence of additional genetic defects. We show that extra centrosomes increase tumor initiation in a mouse model of intestinal neoplasia. Most importantly, we demonstrate that supernumerary centrosomes are sufficient to drive development of spontaneous tumors in multiple tissues. Tumors with centrosome amplification exhibit frequent mitotic errors and possess complex karyotypes, recapitulating a common feature of human cancer. Together, our data support a direct causal relationship between centrosome amplification, genomic instability and tumor development. The sequences in this dataset result from random whole-genome DNA sequencing of spontaneous T- cell lymphomas, B-cell lymphomas, squamous cell carcinomas and one sarcoma from doxycycline-treated Plk4 mice.
Project description:While aneuploidy is found in more than 90% of solid tumors, it is unclear whether aneuploidy is the cause or the consequence of tumorigenesis. Different mouse models deficient in centrosomal or spindle checkpoint proteins that induce aneuploidy show either a promotion or a decrease in tumorigenesis depending on the tissues and the types of oncogenic stimuli. To investigate the effects of aneuploidy in skin development and tumorigenesis, we used Plk4 over-expression (Plk4OE) during epidermal development to assess centrosome amplification and aneuploidy. We found that PLK4OE in the developing epidermis induced centrosome amplification and multipolar divisions, consequently led to p53 stabilization and apoptosis of epidermal progenitors. This delayed epidermal stratification and induced lethal skin barrier defect in 50% of the mice. Plk4 transgene expression was shutdown postnatally in the surviving mice and PLK4OE mice never developed spontaneous skin tumors. Concomitant Plk4OE and P53 deletion (PLK4OE/p53cKO) rescued the defects in differentiation and stratification. Unexpectedly, p53 deletion did not rescue the apoptosis or eventual elimination of the cells overexpressing PLK4 and presenting multiple centrosomes. Remarkably, the short term presence of cells with supernumerary centrosomes postnatally was sufficient to generate aneuploidy and triggered spontaneous skin cancers with complete penetrance. These results reveal for the first time that aneuploidy induced by centrosome amplification, even if transient, can trigger tumorigenesis.
Project description:We performed quantitative proteomics analysis by Stable Isotope Labelling by Amino Acids in Cell culture (SILAC) to understand how centrosome amplification changes the composition of human small extracellular vesicles. We carried out SILAC labelling with medium and heavy isotopes, as it enables the exclusion of contaminant serum proteins, which would be unlabeled (equivalent of light labeling), as well as allowing for simultaneous processing of purification steps to decrease sample-to-sample variability. We isolated small extracellular vesicles by ultracentifugation followed by size exclusion chromatography (SEC). All experiments were performed in duplicate with switched SILAC labelling.