Marteil, G. | Search bioRxiv

bioRxiv2023

High prevalence and dependence of centrosome clustering in mesenchymal tumors and leukemia

The presence of supernumerary centrosomes is a hallmark of cancer and is frequently observed in aggressive tumors. Cancer cells with centrosome amplification achieve pseudo-bipolar spindles through specific coping mechanisms in order to survive. However, their distribution and prevalence in cancer remain largely unknown. Here, using the NCI60 panel of cancer cell lines, we show that the presence of coping strategies correlates with centrosome amplification, with the clustering of extra-centrosomes within the two spindle poles being the most widespread mechanism. Moreover, we report an association between centrosome clustering ability and the epithelial-to-mesenchymal transition (EMT) and observe that the induction of mesenchymal characteristics in breast cancer cells with centrosome amplification promotes clustering. Furthermore, we unveil hematological malignancies, which lack epithelial characteristics, as the most proficient in centrosome clustering. Finally, we show that acute lymphoblastic leukemia is particularly sensitive to targeting clustering through inhibition of the spindle assembly checkpoint. Our study reveals how centrosome clustering and the EMT collaborate to promote carcinogenesis, suggesting new possibilities to treat tumors with low epithelial characteristics, in particular leukemias. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=74 SRC="FIGDIR/small/532472v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@12a713dorg.highwire.dtl.DTLVardef@1706edborg.highwire.dtl.DTLVardef@7deea7org.highwire.dtl.DTLVardef@1bf2280_HPS_FORMAT_FIGEXP M_FIG C_FIG O_LICentrosome clustering is widespread in the NCI60 panel and particularly strong in leukemia. C_LIO_LIThe EMT enhances the ability of cancer cells to cope with multiple centrosomes through centrosome clustering. C_LIO_LICentrosome clustering gene expression peaks at the invasive stage and has prognostic value in breast cancer. C_LIO_LIThe inhibition of MPS1 is a good strategy to promote the death of acute lymphoblastic leukemia (ALL) cells with CA. C_LI

cancer biology↗

bioRxiv2022

Polo-like kinase 4 (Plk4) potentiates anoikis-resistance of p53KO mammary epithelial cells by inducing a hybrid EMT phenotype

Polo-like kinase 4 (Plk4), the major regulator of centriole biogenesis, has emerged as a putative therapeutic target in cancer due to its abnormal expression in human carcinomas, leading to centrosome number deregulation, mitotic defects and chromosomal instability. Moreover, Plk4 deregulation promotes tumor growth and metastasis in mouse models and is significantly associated with poor patient prognosis. Here, we further investigate the role of Plk4 in carcinogenesis and show that its overexpression significantly potentiates resistance to cell death by anoikis of non-tumorigenic p53 knock-out (p53KO) mammary epithelial cells. Importantly, this effect is independent of Plk4s role in centrosome biogenesis, suggesting that this kinase has additional cellular functions. Interestingly, the Plk4-induced anoikis resistance is associated with the induction of a stable hybrid epithelial-mesenchymal phenotype and is partially dependent on P-cadherin upregulation. Furthermore, we found that the conditioned media of Plk4-induced p53KO mammary epithelial cells also induces anoikis resistance of breast cancer cells in a paracrine way, being also partially dependent on soluble P-cadherin secretion. Our work shows, for the first time, that high expression levels of Plk4 induce anoikis resistance of both mammary epithelial cells with p53KO background, as well as of breast cancer cells exposed to their secretome, which is partially mediated through P-cadherin upregulation. These results reinforce the idea that Plk4, independently of its role in centrosome biogenesis, functions as an oncogene, by impacting the tumor microenvironment to promote malignancy.

cancer biology↗