Focal adhesion kinase (FAK) mediates tumor cell–intrinsic behaviors that promote tumor growth and metastasis. We previously showed that FAK also induces the expression of inflammatory genes that inhibit antitumor immunity in the microenvironment. Here, we identified a crucial, previously unknown role for the dual-function cytokine IL-33 in FAK-dependent immune evasion. In murine squamous cell carcinoma (SCC) cells, specifically nuclear FAK enhanced the expression of the genes encoding IL-33, the chemokine CCL5, and the soluble, secreted form of the IL-33 receptor sST2. The abundance of IL-33 and CCL5 was increased in FAK-positive SCC cells but not in normal keratinocytes. IL-33 associated with FAK in the nucleus, and the FAK–IL-33 complex interacted with a network of chromatin modifiers and transcriptional regulators, including TAF9, WDR82 and BRD4, which promote the activity of nuclear factor κB (NF-κB) and its induction of genes encoding chemokines, including CCL5. We did not detect secretion of IL-33 from FAK-positive SCC cells; thus, we propose that the increased production and secretion of sST2 likely sequesters IL-33 secreted by other cell types within the tumor environment, thus blocking its stimulatory effects on infiltrating host immune cells. Depleting FAK, IL-33, or sST2 from SCC cells before implantation induced tumor regression in syngeneic mice, except when CD8+ T cells were co-depleted. Our data provide mechanistic insight into how FAK controls the tumour immune environment, namely through a transcriptional regulatory network mediated by nuclear IL-33. Targeting this axis may boost antitumor immunity in patients.

Many cancers possess an incorrect number of chromosomes, a state described as aneuploidy. Aneuploidy is often caused by Chromosomal Instability (CIN), a process of continuous chromosome mis-segregation. CIN is believed to endow tumours with enhanced evolutionary capabilities due to increased intratumour heterogeneity, and facilitating adaptive resistance to therapies. Recently, however, additional consequences and associations with CIN have been revealed, prompting the need to understand this universal hallmark of cancer in a multifaceted context. This review is focused on the investigation of possible links between CIN, metastasis and the host immune system in cancer development and treatment. We specifically focus on these links since most cancer deaths are due to the consequences of metastasis, and immunotherapy is a rapidly expanding novel avenue of cancer therapy.

Background A major driver of cancer chromosomal instability is replication stress, the slowing or stalling of DNA replication. How replication stress and genomic instability are connected is not known. Aphidicolin-induced replication stress induces breakages at common fragile sites, but the exact causes of fragility are debated, and acute genomic consequences of replication stress are not fully explored. Results We characterize DNA copy number alterations (CNAs) in single, diploid non-transformed cells, caused by one cell cycle in the presence of either aphidicolin or hydroxyurea. Multiple types of CNAs are generated, associated with different genomic regions and features, and observed copy number landscapes are distinct between aphidicolin and hydroxyurea-induced replication stress. Coupling cell type-specific analysis of CNAs to gene expression and single-cell replication timing analyses pinpointed the causative large genes of the most recurrent chromosome-scale CNAs in aphidicolin. These are clustered on chromosome 7 in RPE1 epithelial cells but chromosome 1 in BJ fibroblasts. Chromosome arm level CNAs also generate acentric lagging chromatin and micronuclei containing these chromosomes. Conclusions Chromosomal instability driven by replication stress occurs via focal CNAs and chromosome arm scale changes, with the latter confined to a very small subset of chromosome regions, potentially heavily skewing cancer genome evolution. Different inducers of replication stress lead to distinctive CNA landscapes providing the opportunity to derive copy number signatures of specific replication stress mechanisms. Single-cell CNA analysis thus reveals the impact of replication stress on the genome, providing insights into the molecular mechanisms which fuel chromosomal instability in cancer.

Cancer cells display persistent underlying chromosomal instability, with individual tumour types intriguingly exhibiting characteristic subsets of whole, and subchromosomal aneuploidies. Few methods to induce specific aneuploidies will exist, hampering investigation of functional consequences of recurrent aneuploidies, as well as the acute consequences of specific chromosome mis‐segregation. We therefore investigated the possibility of sabotaging the mitotic segregation of specific chromosomes using nuclease‐dead CRISPR‐Cas9 (dCas9) as a cargo carrier to specific genomic loci. We recruited the kinetochore‐nucleating domain of centromere protein CENP‐T to assemble ectopic kinetochores either near the centromere of chromosome 9, or the telomere of chromosome 1. Ectopic kinetochore assembly led to increased chromosome instability and partial aneuploidy of the target chromosomes, providing the potential to induce specific chromosome mis‐segregation events in a range of cell types. We also provide an analysis of putative endogenous repeats that could support ectopic kinetochore formation. Overall, our findings provide new insights into ectopic kinetochore biology and represent an important step towards investigating the role of specific aneuploidy and chromosome mis‐segregation events in diseases associated with aneuploidy.

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Cancer cells display persistent underlying chromosomal instability that results in chromosome mis-segregation, the formation of micronuclei, and abnormal numbers of chromosomes (aneuploidy). These features are common to nearly all human cancers, with individual tumour types intriguingly exhibiting characteristic subsets of whole, and sub-chromosomal aneuploidies. To date, few methods to induce specific aneuploidies at will exist, hampering the investigation of functional consequences of recurrent aneuploidies. Moreover, although some human cell lines with specific aneuploidies exist, the acute cellular responses to specific chromosomal instability events remain unknown. We therefore investigated the possibility of sabotaging the mitotic segregation of specific chromosomes using nuclease-dead CRISPR-Cas9 (dCas9) as a cargo carrier to specific genomic loci. We recruited the kinetochore-nucleating domain of centromere protein CENP-T to assemble ectopic kinetochores either near the centromere of chromosome 9, or the telomere of chromosome 1. Ectopic kinetochore assembly led to increased chromosome instability and aneuploidy of the target chromosomes, providing the potential to create ‘designer karyotypes’ and study their immediate downstream cellular responses in a wide range of cell types. Overall, our findings provide new insights into ectopic kinetochore biology, and also represent an important step towards investigating the role of specific aneuploidy and chromosome mis-segregation events in diseases associated with aneuploidy.

Understanding the factors that explain why people move – or stay – and where they go, is a central goal of migration research. This article improves our understanding of migration aspirations of professionals in Europe by leveraging a previously untapped data source: aggregate-level information on LinkedIn users open to work-related international relocation, accessed through the LinkedIn Recruiter platform. We collected data at regular intervals from Oct. 2020 to Sept. 2021. First, we offer descriptive statistics of proxies for migration aspirations (or lack thereof) for millions of Linkedin users in Europe. Then we approach our questions using a standardization technique, based on gravity models of migration, in order to account for a number of biases in the data, including uneven use of LinkedIn across countries. We found that, in absolute terms, countries in Northern and Western Europe are the most attractive ones when considering LinkedIn users open to work-related relocation (about 60%), followed by Southern Europe (about 40%) and Eastern Europe (30%). We also observed substantial heterogeneity in directionality of aspirations: for example, roughly 20% of LinkedIn users would relocate from Western to Northern Europe, while less than 10% would relocate from Northern to Western Europe. After accounting for differences in population density, geographic and linguistic distances, as well as internet and LinkedIn penetration, we observed that, in relative terms, Southern Europe appears to be a highly desired destination for professionals, indicating that there is potential for changing patterns in actual flows, should more opportunities for professionals arise in Southern Europe.