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Manninen, A.

Publications and source records attributed to Manninen, A..

8 recordsLinked to original sources

β4-integrins safeguard nuclear mechanics to suppress prostate cancer progression

Prostate cancer (PCa) progression is accompanied by profound alterations in cell-extracellular matrix (ECM) adhesion, nuclear architecture and mechanical adaptability, yet the molecular mechanisms linking these processes remain poorly understood. Hemidesmosomes (HDs), formed by 6{beta}4-integrins, anchor epithelial cells to the basement membrane and couple extracellular forces to the intermediate filament (IF) cytoskeleton. Here, we identify a previously unrecognized tumor-suppressive function of {beta}4-integrins in preserving nuclear integrity in prostate epithelial cells. Loss of {beta}4-integrins disrupted the cytokeratin-5 network and its coupling to the nucleus, leading to nuclear softening, lamin remodeling, reduced heterochromatin content and enhanced confined migration. Unexpectedly, proximity-labeling proteomics revealed that {beta}4-integrins engage nuclear pore complex (NPC) components in an 6-independent manner, particularly upon HD disassembly. Selected interactions were validated using proximity ligation and co-immunoprecipitation assays. {beta}4-integrin loss was associated with enlarged nuclear pores and aberrant nucleocytoplasmic transport, including nuclear accumulation of YAP1. Consistent with these findings, reduced {beta}4-integrin expression in a large PCa tissue cohort correlated with altered nuclear morphology, adverse clinicopathological features, metastatic progression, and poor patient survival. Collectively, our study establishes {beta}4-integrins as a critical molecular link between cell-ECM adhesion, nuclear mechanics and genome integrity.

cancer biology↗

Epithelial eversion, a collective rearrangement from apical-in to apical-out polarity, is initiated by α6β4 integrins and sustained by increased cell proliferation and anchorage-independence

Epithelial cells primarily segregate transmembrane proteins to apical or basal surfaces, establishing apical-basal polarity. For 3D tissues, apical proteins face inwards and basal proteins are on the outer surfaces (in contact with ECM). Apical-basal polarity can become inverted such that the apical proteins are on the outer surfaces. Originally this polarity inversion was assumed to always occur due to changes in protein trafficking. However, recent work by our group showed that increased RhoA activation causes epithelial spheroids to invert apical-basal polarity via a collective rearrangement of cells, a process we and others have termed eversion. We hypothesized that specific integrin-ECM interactions could facilitate the collective cellular migration required for eversion. Using multiple integrin knockout lines, we observed that epithelial cells lacking either 6 or {beta}4 integrins do not develop apical-out polarity in response to RhoA activation. Similarly, 6 blocking antibody or culturing spheroids in collagen (lacking laminin) also inhibited the formation apical-out polarity. These data indicate that 6{beta}4-laminin interactions are required for eversion. Next, we examined the role of cell proliferation and anchorage independence in maintaining apical-out polarity of everted spheroids. Inhibition of cell proliferation (with DNA synthesis inhibitor aphidicolin) or inhibition of anchorage-independence (with FAK inhibitor 14) were sufficient to restore apical-in polarity to RhoA treated spheroids, indicating that both proliferation and anchorage-independence maintain spheroids in an apical-out state. We also observed that apical-out spheroids can revert to apical-in polarity through apoptotic cavitation of cells located in the center of the spheroids. Lastly, through RNA sequencing we demonstrate that apical-out spheroids have unique gene expression profiles. This study provides new mechanistic insights into the biochemical and biophysical mechanisms that drive eversion and maintain apical-out polarity. This work supports the concept that changing from apical-in to apical-out polarity be an important marker for phenotypic switch in epithelial cells.

cell biology↗

DLL4-Notch3-WNT5B axis is a novel mediator of bi-directional pro-metastatic crosstalk between melanoma and lymphatic endothelial cells

Despite strong indications that melanoma interaction with lymphatic vessels actively promotes melanoma progression, the molecular mechanisms are not yet completely understood. To characterize molecular factors of this crosstalk we established human primary lymphatic endothelial cell (LEC) co-cultures with human melanoma cell lines. Here, we show that co-culture with melanoma cells induced transcriptomic changes in LECs and led to multiple alterations in their function. WNT5B, a paracrine signaling molecule upregulated in melanoma cells upon LEC interaction, was found contributing to the functional changes in LECs. Moreover, WNT5B transcription was regulated by Notch3 in melanoma cells following the co-culture with LECs, and Notch3 and WNT5B were co-expressed in melanoma patient primary tumor and metastasis samples. Moreover, melanoma cells derived from LEC co-culture escaped efficiently from the primary site to the proximal tumor draining lymph nodes, which was impaired upon WNT5B depletion. This supports the role of WNT5B in promoting the metastatic potential of melanoma cells through its effects on LECs. Finally, DLL4, a Notch ligand expressed in LECs, was identified as an upstream inducer of the Notch3-WNT5B axis in melanoma. This study elucidates WNT5B as a novel molecular factor mediating bi-directional crosstalk between melanoma cells and lymphatic endothelium and promoting melanoma metastasis.

cancer biology↗

TEAD1 regulates ITGA1 and ITGA2 to control prostate cancer progression

The extracellular matrix (ECM) undergoes significant changes during prostate cancer (PCa) progression and actively regulates PCa growth and invasion. Here, we performed a meta-analysis of PCa cohorts and found that downregulation or loss of ITGA1 and ITGA2 integrin genes was associated with tumor progression to metastasis and poor prognosis in PCa patients. Genomic deletion of both 1- and 2-integrins activated epithelial-to-mesenchymal transition (EMT) in benign prostate epithelial cells, thereby enhancing their invasive potential in vitro and converting them into tumorigenic cells in vivo. Mechanistically, EMT was induced by enhanced secretion and subsequent activation of autocrine TGF{beta}1 and nuclear targeting of YAP1. Our unbiased genome-wide co-expression analysis of large PCa cohort datasets identified the transcription factor TEAD1 as a key regulator of ITGA1 and ITGA2 expression in PCa cells while TEAD1 loss phenocopied the dual loss of 2- and 2-integrins in vitro and in vivo. Notably, clinical data analysis revealed that TEAD1 downregulation or loss was associated with aggressive PCa and could synergize with ITGA1 and ITGA2 expression to impact PCa prognosis and progression. Altogether, our results demonstrate that loss of 1- and 2-integrins, either via deletion/inactivation of the ITGA1/ITGA2 locus or via loss of TEAD1, contributes to PCa progression by inducing TGF{beta}1-driven EMT.

cancer biology↗

Disassembly of hemidesmosomes promotes tumorigenesis in PTEN-negative prostate cancer by targeting plectin into focal adhesions

Loss of 6{beta}4-dependent hemidesmosomes has been observed during prostate cancer progression. However, the significance and underlying mechanisms by which aberrant hemidesmosome assembly may modulate tumorigenesis remain elusive. Using an extensive CRISPR/Cas9-mediated genetic engineering approaches in different prostate cancer cell lines combined with in vivo tumorigenesis studies in mice, bone marrow-on-chip assays and bioinformatics, as well as histological analysis of prostate cancer patient cohorts, we demonstrated that simultaneous loss of PTEN and hemidesmosomes induced several tumorigenic properties including proliferation, migration, resistance to anoikis, apoptosis, and drug treatment in vitro, and increased metastatic capacity in vivo. Our studies showed that these effects were driven by activation of EGFR/PI3K/Akt and FAK/Src-pathways and were abolished by plectin downregulation. Therefore, dual loss of PTEN and hemidesmosomes may have diagnostic value helping to stratify prostate cancer patients with high risk for development of aggressive disease and highlight plectin as a potential therapeutic target in prostate cancer.

cancer biology↗

Extensive germline-somatic interplay drives prostate cancer through HNF1B co-option of TMPRSS2-ERG

Genome-wide association studies have identified 270 loci conferring risk for prostate cancer (PCa), yet the underlying biology and clinical impact remain to be investigated. Here we observe an enrichment of transcription factor genes including HNF1B within PCa risk-associated regions. While focused on the 17q12/HNF1B locus, we find a strong eQTL for HNF1B and multiple potential causal variants involved in the regulation of HNF1B expression in PCa. An unbiased genome-wide co-expression analysis reveals PCa-specific somatic TMPRSS2-ERG fusion as a transcriptional mediator of this locus and the HNF1B eQTL signal is ERG fusion status dependent. We investigate the role of HNF1B and find its involvement in several pathways related to cell cycle progression and PCa severity. Furthermore, HNF1B interacts with TMPRSS2-ERG to co-occupy large proportion of genomic regions with a remarkable enrichment of additional PCa risk alleles. We finally show that HNF1B co-opts ERG fusion to mediate mechanistic and biological effects of the PCa risk-associated locus 17p13.3/VPS53/FAM57A/GEMIN4. Taken together, we report an extensive germline-somatic interaction between TMPRSS2-ERG fusion and genetic variations underpinning PCa risk association and progression.

cancer biology↗

Temporally and Spatially Regulated Collagen XVIII Isoforms Impact Ureteric Patterning Through Their TSP1-like Domain

Collagen XVIII (ColXVIII) is a component of the extracellular matrix implicated in embryogenesis and control of homeostasis. We provide evidence that ColXVIII has a specific role in kidney ontogenesis by regulating the interaction between mesenchymal and epithelial tissues as observed in analyses of total and isoform-specific knockout embryos, mice, and ex vivo organ primordia. ColXVIII deficiency, both temporally and spatially, impacts the 3D pattern of ureteric tree branching morphogenesis via its specific isoforms. Proper development of ureteric tree depends on a tight control of the nephron progenitor cells (NPCs). ColXVIII-deficient NPCs are leaving the NPC pool faster than in controls. Moreover, the data suggests that ColXVIII mediates the kidney epithelial tree patterning via its N-terminal domains, and especially the Thrombospondin-1-like domain, and that this morphogenetic effect involves ureteric epithelial integrins. Altogether, the results propose a significant role for ColXVIII in a complex signalling network regulating renal progenitors and kidney development.

developmental biology↗

The pro-oncogenic adaptor CIN85 inhibits hypoxia-inducible factor prolyl hydroxylase-2

The EGFR-adaptor protein CIN85 has been shown to promote breast cancer malignancy and hypoxia-inducible factor (HIF) stability. However, the mechanisms underlying cancer promotion remain ill-defined. Here, we show that CIN85 is a novel binding partner of the main HIF-prolyl hydroxylase PHD2, but not of PHD1 or PHD3. Mechanistically, the N-terminal SH3 domains of CIN85 interact with the proline-arginine rich region within the N-terminus of PHD2, thereby inhibiting PHD2 activity and HIF-degradation. This activity is essential in vivo, as specific loss of the CIN85-PHD2 interaction in CRISPR/Cas9 edited cells affected growth and migration properties as well as tumor growth in mice. Overall, we discovered a previously unrecognized tumor growth checkpoint that is regulated by CIN85-PHD2, and uncovered an essential survival function in tumor cells linking growth factor adaptors with hypoxia signaling.

biochemistry↗