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Cabezas-Sainz, P.

Publications and source records attributed to Cabezas-Sainz, P..

3 recordsLinked to original sources

Red blood cell-tumour cell interactions promote tumour cell progression

One critical step in the metastatic cascade is the survival of circulating tumour cells (CTCs) within the bloodstream. While numerous interactions between CTCs and various hematopoietic cells have been described, the role of red blood cells (RBCs) in this process remains underexplored. This study investigates the interactions between tumour cells and RBCs from breast and lung cancer patients, revealing significant phenotypic and functional changes in the tumour cells, unlike when the contact is with RBCs from healthy donors. In vitro co-culture of cancer cell lines with RBCs from metastatic cancer patients resulted in increased tumour cell attachment accompanied by morphological changes. Additionally, RBCs-primed tumour cells showed increased adhesion and disruption of the endothelial barrier in vitro and increased invasiveness both in vitro and in vivo. Transcriptomic analysis showed that RBCs from metastatic breast cancer patients induce significant gene expression changes, notably upregulating PAK4, which enhances migration and epithelial-mesenchymal transition. PAK4 inhibition reduced these effects. Proteomic studies revealed substantial remodelling, including actin-related changes and the accumulation of VASP at cell edges, promoting directional migration. Clinically, higher RBC distribution width (RDW) in metastatic breast cancer patients is associated with increased CTC counts and worse outcome. This study highlights the previously unrecognized role of RBCs in promoting metastatic behaviours in cancer cells and suggests potential therapeutic targets, such as PAK4, to counteract these effects. Further exploration of RBCs-tumour cell interactions could provide new insights into metastatic mechanisms and improve cancer prognosis and treatment strategies. Key PointsO_LIThis study reveals the previously unknown role of RBCs in enhancing tumour cell invasiveness and metastatic potential. C_LIO_LITumour cells undergo significant phenotypic and functional changes after contact with RBCs from cancer patients. C_LI

cancer biology↗

CRISPR targeting of FOXL2 c.402C>G mutation reduces malignant phenotype in granulosa tumor cells and identifies anti-tumoral compounds

FOXL2 is a transcription factor essential for sex determination and ovary development and maintenance. Mutations in this gene are implicated in syndromes involving premature ovarian failure and granulosa cell tumors (GCTs). This rare cancer accounts for less than 5% of diagnosed ovarian cancers and is causally associated with the FOXL2 c.402C>G, p.C134W mutation in 97% of the adult cases (AGCTs). In this study, we employed CRISPR technology to specifically eliminate the FOXL2 c.402C>G mutation in granulosa tumor cells. Our results show that this Cas9-mediated strategy selectively targets the mutation without affecting the wild-type allele. Granulosa cells lacking the FOXL2 c.402C>G exhibit a reduced malignant phenotype, with significant changes in cell proliferation, invasion, and cell death. Furthermore, these modified cells are more susceptible to Dasatinib and Ketoconazole. Transcriptomic and proteomic analyses reveal that CRISPR-modified granulosa tumor cells shift their expression profiles towards a wild-type like phenotype. Additionally, this altered expression signature has led to the identification of new compounds with antiproliferative and pro-apoptotic effects on granulosa tumor cells. Our findings demonstrate the potential of CRISPR technology for the specific targeting and elimination of a mutation causing granulosa cell tumors, highlighting its therapeutic promise for treating this rare ovarian cancer. Simple SummaryAdult granulosa cell tumors (AGCTs), characterized by a specific point mutation (C134W) in the gene FOXL2, are less than 5% of all the diagnosed ovarian cancers. Surgery is the cornerstone treatment for AGCT even at relapse, with systemic therapy showing poor results. The aim of our study is to explore the potential therapeutic effect of the elimination of the C134W mutation. To achieve our goal, we have eliminated the mutant allele using CRISPR technology. Our results demonstrate that CRISPR-mediated elimination of FOXL2-C134W reduces the malignant phenotype of granulosa tumor cells, which change their transcriptional, proteomic, and cellular phenotype to a wild type like, granulosa type. Moreover, the induced changes allowed us to find new compounds with antitumoral activity. This work highlights the therapeutic potential of CRISPR mediated technology for the treatment of AGCT.

cancer biology↗

Targeting the mitochondrial RNA methyltransferase TRMT61B reveals new therapeutic opportunities in aneuploid cancer cells

Chromosomal instability (CIN) is an important source of genetic and phenotypic variation that has been extensively reported as a critical cancer related property that improves tumor cell adaptation and survival. CIN and its immediate consequence, aneuploidy, provoke adverse effects on cellular homeostasis that need to be overcome by developing efficient anti-stress mechanisms. Perturbations in these safeguard responses might be detrimental for cancer cells and represent an important tumor specific Achilles heel since CIN and aneuploidy are very rare events in normal cells. On the other hand, epitranscriptomic marks catalyzed by different RNA modifying enzymes have been found to change under several stress insults. Although CIN and aneuploidy are important intracellular stressors, their biological connection with RNA modifications is pending to be determined. In an in silico search for new cancer biomarkers, we have identified TRMT61B, a mitochondrial RNA methyltransferase enzyme, to be associated with high levels of aneuploidy. In the present work, we study the connection of this molecule with cancer and aneuploidy. First, we show increased protein amounts of TRMT61B in tumor cell lines with imbalanced karyotype as well as in different tumor types compared to unaffected control tissues. In addition, we demonstrate that depletion of TRMT61B in melanoma cells reduces cell proliferation either by fostering apoptosis and inhibiting autophagy in high-aneuploid (ANEhigh) cells or by inducing senescence in the case of low-aneuploid (ANElow) cell lines. Further, TRMT61B elimination compromises mitochondrial function and reduces the expression of several mitochondrial encoded proteins that are part of the electron transport chain. Finally, transwell and xenograft experiments revealed a reduced invasive and tumorigenic capacity upon TRMT61B depletion that strengthen the therapeutic value of this aneuploidy-associated biomarker. These results, which connect tumorigenesis, aneuploidy and mitochondrial RNA methylation, bring to the cancer field a new putative strategy to specifically target high aneuploid tumors.

cancer biology↗