Project description:Pancreatic ductal adenocarcinoma (PDAC) frequently metastasizes into the peritoneum, which contributes to poor prognosis. Metastatic spreading is promoted by cancer cell plasticity, yet its regulation by the microenvironment is incompletely understood. Here, we show that the presence of hyaluronan and proteoglycan link protein-1 (HAPLN1) in the extracellular matrix enhances tumor cell plasticity and PDAC metastasis. Bioinformatic analysis showed that HAPLN1 expression is enriched in the basal PDAC subtype and associated with worse overall patient survival. In a mouse model for peritoneal carcinomatosis, HAPLN1-induced immunomodulation favored a more permissive microenvironment, which accelerated the peritoneal spread of tumor cells. Mechanistically, HAPLN1, via upregulation of tumor necrosis factor receptor 2 (TNFR2), promoted TNF-mediated upregulation of Hyaluronan (HA) production, facilitating EMT, stemness, invasion and immunomodulation. Extracellular HAPLN1 modified cancer cells and fibroblasts, rendering them more immunomodulatory. As such, we identified HAPLN1 as a prognostic marker and as a driver for peritoneal metastasis in PDAC.
Project description:Pancreatic ductal adenocarcinoma (PDAC) frequently metastasizes into the peritoneum, which contributes to poor prognosis. Metastatic spreading is promoted by cancer cell plasticity, yet its regulation by the microenvironment is incompletely understood. Here, we show that the presence of hyaluronan and proteoglycan link protein-1 (HAPLN1) in the extracellular matrix enhances tumor cell plasticity and PDAC metastasis. Bioinformatic analysis showed that HAPLN1 expression is enriched in the basal PDAC subtype and associated with worse overall patient survival. In a mouse model for peritoneal carcinomatosis, HAPLN1-induced immunomodulation favors a more permissive microenvironment, which accelerates the peritoneal spread of tumor cells. Mechanistically, HAPLN1, via upregulation of tumor necrosis factor receptor 2 (TNFR2), promotes TNF-mediated upregulation of Hyaluronan (HA) production, facilitating EMT, stemness, invasion and immunomodulation. Extracellular HAPLN1 modifies cancer cells and fibroblasts, rendering them more immunomodulatory. As such, we identify HAPLN1 as a prognostic marker and as a driver for peritoneal metastasis in PDAC.
Project description:Diffuse-type gastric cancer (DGC) frequently metastasizes to the peritoneal cavity and causes malignant ascites. Although recent studies revealed that RHOA mutation and CLDN18-ARHGAP6/26 fusions are a hallmark of DGC, their roles are largely unknown. Here, we report the roles of two novel ARHGAP fusions (RP2-ARHGAP6 and OCLN-ARHGAP26) and the above CLDN18-ARHGAP26 fusion in ascites-derived DGC cell lines. A series of experiments revealed that X-ARHGAP6 /26 fusion acts as an inhibitor of RhoA and further suggested that the ARHGAP6 fusion induces cell-adhesion loss and maintains a putative ALDH-high cancer stem cell population, whereas the ARHGAP26 fusion evades apoptosis. Notably, these ARHGAP6/26 fusions were frequently found not only in the ascites of DGC but also in that of pancreatic cancer (12% and 38%, respectively). Together, these data demonstrate that ARHGAP6/26 fusions are useful for developing therapeutics and diagnostics for peritoneal metastasis control of DGC and pancreatic cancer. We used microarrays to identify gene sets regulated by RP2-ARHGAP6-centered signaling in DGC cells.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is a heterogeneous cancer in which differences in survival rates might be related to a variety in gene expression profiles. Although the molecular biology of PDAC begins to be revealed, genes or pathways that specifically drive tumour progression or metastasis are not well understood. Therefore, we performed microarray analyses on whole-tumour samples of 2 human PDAC subpopulations with similar clinicopathological features, but extremely distinct survival rates after potentially curative surgery, i.e., good outcome (OS and DFSM-bM-^@M-^I>M-bM-^@M-^I50M-bM-^@M-^Imonths) versus bad outcome (OSM-bM-^@M-^I<M-bM-^@M-^I19M-bM-^@M-^Imonths and DFSM-bM-^@M-^I<M-bM-^@M-^I7M-bM-^@M-^Imonths). Additionally, liver- and peritoneal metastases were analysed and compared to primary cancer tissue. The integrin and ephrin receptor families were upregulated in all PDAC samples, irrespective of outcome, supporting an important role of the interaction between pancreatic cancer cells and the surrounding desmoplastic reaction in tumorigenesis and cancer progression. Moreover, some components, such as ITGB1 and EPHA2, were upregulated in PDAC samples with a poor outcome, Additionally, overexpression of the non-canonical Wnt/M-NM-2-catenin pathway and EMT genes in PDAC samples with bad versus good outcome suggests their contribution to the invasiveness of pancreatic cancer, with M-NM-2-catenin being also highly upregulated in metastatic tissue. Thus, we conclude that components of the integrin and ephrin pathways and EMT-related genes might serve as molecular markers in pancreatic cancer as their expression seems to be related with prognosis. Microarray analysis was performed on 'Good' and 'Bad' patient samples (samples with similar pathological characteristics were chosen based on the definition of the 2 diverse survival outcome groups and the required RIN values above 7.1), on surrounding non-tumoural pancreatic control samples, liver metastasis (LM) and peritoneal metastasis (PM). Comparisons between good vs. control, bad vs. control, good vs. bad, and primary pancreatic cancer versus metastasis were performed.
Project description:Cancer metastasis requires the transient activation of cellular programs enabling dissemination and seeding in distant organs. Genetic, transcriptional and translational heterogeneity contributes to this dynamic process. Metabolic heterogeneity has also been observed, yet its role for cancer progression is less explored. Here, we discover that loss of phosphoglycerate dehydrogenase (PHGDH) potentiates metastatic dissemination. Specifically, we find that heterogeneous or low PHGDH expression in primary tumors of breast cancer patients is associated with decreased metastasis free survival time. In mice, circulating tumor cells and early metastatic lesions are enriched with PHGDH low cancer cells and silencing PHGDH in primary tumors increases metastasis formation. Mechanistically, PHGDH protein interacts with the glycolytic enzyme phosphofructokinase (PFK) and the loss of this interaction activates the hexosamine – sialic acid pathway, which provides precursors for protein glycosylation. Consequently, aberrant protein glycosylation including increased sialylation of integrin αvβ3 occurs, which potentiates cell migration and invasion. Inhibition of sialic acid metabolism counteracts the metastatic capacity of PHGDH low cancer cells. In conclusion, while the catalytic activity of PHGDH supports cancer cell proliferation, low PHGDH protein expression non-catalytically potentiates cancer dissemination and metastasis formation. Thus, the presence of PHDGH heterogeneity in primary tumors may be considered a sign of tumor aggressiveness.
Project description:Triple-Negative Breast Cancer (TNBC) has a poor prognosis and adverse clinical outcomes among all breast cancer subtypes as there is no available targeted therapy. Overexpression of Enhancer of zeste homolog 2 (EZH2) has been shown to correlate with TNBC's poor prognosis, but the contribution of EZH2 catalytic (H3K27me3) versus non-catalytic EZH2 (NC-EZH2) function in TNBC progression remains elusive. We reveal that selective hyper-activation of functional EZH2 (H3K27me3) over NC-EZH2 alters TNBC metastatic landscape and fosters its peritoneal metastasis, particularly splenic. Instead of H3K27me3-mediated repression of gene expression; here, it promotes KRT14 transcription by attenuating binding of repressor Sp1 to its promoter. Further, KRT14 loss significantly reduces TNBC migration, invasion, and peritoneal metastasis. Consistently, human TNBC metastasis displays positive correlation between H3K27me3 and KRT14 levels. Finally, EZH2 knockdown or H3K27me3 inhibition by EPZ6438 reduces TNBC peritoneal metastasis. Altogether, our preclinical findings suggest a rationale for targeting TNBC with EZH2 inhibitors.
Project description:To investigate the role of HAPLN1 in multiple myeloma, we treated RPMI8226 multiple myeloma cells with recombinant HAPLN1-PTR1. We then performed gene expression profiling analysis using data obtained from RNA-seq.
Project description:To identify the HAPLN1-induced genes regulated by STAT1 in multiple myeloma, we treated RPMI8226 multiple myeloma cells (WT or STAT1 KO) with recominant HAPLN1-PTR1. We then performed gene expression profiling analysis using data obtained from RNA-seq.