Esophageal adenocarcinoma (EAC) has a dismal prognosis, and survival benefits of recent multimodality treatments remain small. Cancer-associated fibroblasts (CAFs) are known to contribute to poor ...outcome by conferring therapy resistance to various cancer types, but this has not been explored in EAC. Importantly, a targeted strategy to circumvent CAF-induced resistance has yet to be identified. By using EAC patient-derived CAFs, organoid cultures, and xenograft models we identified IL-6 as the stromal driver of therapy resistance in EAC. IL-6 activated epithelial-to-mesenchymal transition in cancer cells, which was accompanied by enhanced treatment resistance, migratory capacity, and clonogenicity. Inhibition of IL-6 restored drug sensitivity in patient-derived organoid cultures and cell lines. Analysis of patient gene expression profiles identified ADAM12 as a noninflammation-related serum-borne marker for IL-6–producing CAFs, and serum levels of this marker predicted unfavorable responses to neoadjuvant chemoradiation in EAC patients. These results demonstrate a stromal contribution to therapy resistance in EAC. This signaling can be targeted to resensitize EAC to therapy, and its activity can be measured using serum-borne markers.
Mesothelioma has been regarded as a nonimmunogenic tumor, which is also shown by the low response rates to treatments targeting the PD-1/PD-L1 axis. Previously, we demonstrated that autologous tumor ...lysate-pulsed dendritic cell (DC) immunotherapy increased T-cell response toward malignant mesothelioma. However, the use of autologous tumor material hampers implementation in large clinical trials, which might be overcome by using allogeneic tumor cell lines as tumor antigen source. The purpose of this study was to investigate whether allogeneic lysate-pulsed DC immunotherapy is effective in mice and safe in humans.
First, in two murine mesothelioma models, mice were treated with autologous DCs pulsed with either autologous or allogeneic tumor lysate or injected with PBS (negative control). Survival and tumor-directed T-cell responses of these mice were monitored. Results were taken forward in a first-in-human clinical trial, in which 9 patients were treated with 10, 25, or 50 million DCs per vaccination. DC vaccination consisted of autologous monocyte-derived DCs pulsed with tumor lysate from five mesothelioma cell lines.
In mice, allogeneic lysate-pulsed DC immunotherapy induced tumor-specific T cells and led to an increased survival, to a similar extent as DC immunotherapy with autologous tumor lysate. In the first-in-human clinical trial, no dose-limiting toxicities were established and radiographic responses were observed. Median PFS was 8.8 months 95% confidence interval (CI), 4.1-20.3 and median OS not reached (median follow-up = 22.8 months).
DC immunotherapy with allogeneic tumor lysate is effective in mice and safe and feasible in humans.
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Pancreatic ductal adenocarcinoma (PDAC) has the worst prognosis of all common cancers. However, divergent outcomes exist between patients, suggesting distinct underlying tumor biology. Here, we ...delineated this heterogeneity, compared interconnectivity between classification systems, and experimentally addressed the tumor biology that drives poor outcome. RNA-sequencing of 90 resected specimens and unsupervised classification revealed four subgroups associated with distinct outcomes. The worst-prognosis subtype was characterized by mesenchymal gene signatures. Comparative (network) analysis showed high interconnectivity with previously identified classification schemes and high robustness of the mesenchymal subtype. From species-specific transcript analysis of matching patient-derived xenografts we constructed dedicated classifiers for experimental models. Detailed assessments of tumor growth in subtyped experimental models revealed that a highly invasive growth pattern of mesenchymal subtype tumor cells is responsible for its poor outcome. Concluding, by developing a classification system tailored to experimental models, we have uncovered subtype-specific biology that should be further explored to improve treatment of a group of PDAC patients that currently has little therapeutic benefit from surgical treatment.
Long-term anti-angiogenesis leads to pruned vasculature, densely deposited extracellular matrix (ECM), and consequently reduced chemotherapy delivery in esophagogastric cancer (EGC). To address this ...issue, we evaluated the efficacy of adding a hyaluronidase or a NO-donor to the regimen of chemotherapy and anti-angiogenic drugs.
A patient-derived EGC xenograft model was developed. Grafted mice were randomly assigned to four experimental groups and one control group. The experimental groups received DC101, a murine angiogenesis inhibitor, and nab-paclitaxel (NPTX), with the addition of hyaluronidase (PEGPH20), or NO-donor (nitroglycerine, NTG), or their combination, respectively. We compared tumor growth during 17 days of treatment. We performed immunohistochemistry for ECM components hyaluronan (HA) and collagen, CD31 for endothelial cells, and γH2AX for DNA damage. The positively stained areas were quantified, and vessel diameters were measured using QuPath software.
Prolonged DC101 treatment induced deposition of HA (p<0.01) and collagen (p<0.01). HA was effectively degraded by PEGPH20 (p<0.001), but not by NTG as expected. Both PEGPH20 (p<0.05) and NTG (p<0.01) dilated vessels collapsed in response to long-term DC101 treatment. However, only PEGPH20 (rather than NTG) was found to significantly inhibit tumor growth (p<0.05) in combination with NPTX and DC101.
These findings suggest that the mechanical barrier of HA is the major reason responsible for the resistance developed during prolonged anti-angiogenesis in EGC. Incorporating PEGPH20 into the existing treatment regimen is promising to improve outcomes for patients with EGC.
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•Anti-angiogenesis enhances drug delivery but causes desmoplasia with long-term use.•Dense stroma and vascular regression reduce the efficacy of the cytotoxic agent.•PEGPH20 can restore the long-term benefits of anti-angiogenesis.
Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a limited set of known driver mutations but considerable cancer cell heterogeneity. Phosphoproteomics provides a readout of ...aberrant signaling and has the potential to identify new targets and guide treatment decisions. Using two-step sequential phosphopeptide enrichment, we generate a comprehensive phosphoproteome and proteome of nine PDAC cell lines, encompassing more than 20,000 phosphosites on 5,763 phospho-proteins, including 316 protein kinases. By using integrative inferred kinase activity (INKA) scoring, we identify multiple (parallel) activated kinases that are subsequently matched to kinase inhibitors. Compared with high-dose single-drug treatments, INKA-tailored low-dose 3-drug combinations against multiple targets demonstrate superior efficacy against PDAC cell lines, organoid cultures, and patient-derived xenografts. Overall, this approach is particularly more effective against the aggressive mesenchymal PDAC model compared with the epithelial model in both preclinical settings and may contribute to improved treatment outcomes in PDAC patients.
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•Phosphoproteomics uncovers multiple active kinases in PDAC•Top-ranking hyperactive kinases guide effective combinations•Low-dose 3-drug combinations inhibit tumor growth in vivo•Known molecular subtypes for PDAC align with phosphoproteomics profiles
By profiling PDAC models, Vallés-Martí et al. show that profile-guided drug combinations at low doses are effective in vitro and in vivo. Most effective strategies must target both upstream and downstream effectors captured in the top 10 kinase profiles, with the precise combinations being associated with PDAC subtype.
Pancreatic ductal adenocarcinoma (PDAC) is characterized by an abundance of stroma. Multiple molecular classification efforts have identified a mesenchymal tumor subtype that is consistently ...characterized by high‐grade growth and poor clinical outcome. The relation between PDAC stroma and tumor subtypes is still unclear. Here, we aimed to identify how PDAC cells instruct the main cellular component of stroma, the pancreatic stellate cells (PSCs). We found in primary tissue that high‐grade PDAC had reduced collagen deposition compared to low‐grade PDAC. Xenografts and organotypic co‐cultures established from mesenchymal‐like PDAC cells featured reduced collagen and activated PSC content. Medium transfer experiments using a large set of PDAC cell lines revealed that mesenchymal‐like PDAC cells consistently downregulated ACTA2 and COL1A1 expression in PSCs and reduced proliferation. We identified colony‐stimulating factor 1 as the mesenchymal PDAC‐derived ligand that deactivates PSCs, and inhibition of its receptor CSF1R was able to counteract this effect. In conclusion, high‐grade PDAC features stroma that is low in collagen and activated PSC content, and targeting CSF1R offers direct options to maintain a tumor‐restricting microenvironment.
Synopsis
This study reveals that PDAC cells counteract mechanical restrictions of tumor stroma by secreting CSF‐1, which could be a potential therapeutic target.
Poorly differentiated, high‐grade pancreatic cancers, corresponding with the mesenchymal subtype, feature stroma that is low in collagen and activated pancreatic stellate cell content.
These mesenchymal subtype cancer cells secrete high amounts of CSF‐1.
CSF‐1 downregulates stromal activation markers and reduces proliferation via STAT3 in PSCs.
Depletion of CSF‐1 in high‐grade PDAC abolishes PSC deactivation.
High‐grade CSF‐1‐positive PDAC patient samples exhibit deactivated stroma.
This study reveals that PDAC cells counteract mechanical restrictions of tumor stroma by secreting CSF‐1, which could be a potential therapeutic target.
Effective treatments for pancreatic ductal adenocarcinoma (PDAC) are lacking, and targeted agents have demonstrated limited efficacy. It has been speculated that a rare population of cancer stem ...cells (CSCs) drives growth, therapy resistance, and rapid metastatic progression in PDAC. These CSCs demonstrate high clonogenicity in vitro and tumorigenic potential in vivo. However, their relevance in established PDAC tissue has not been determined. Here, we use marker-independent stochastic clonal labeling, combined with quantitative modeling of tumor expansion, to uncover PDAC tissue growth dynamics. We find that in contrast to the CSC model, all PDAC cells display clonogenic potential in situ. Furthermore, the proximity to activated cancer-associated fibroblasts determines tumor cell clonogenicity. This means that the microenvironment is dominant in defining the clonogenic activity of PDAC cells. Indeed, manipulating the stroma by Hedgehog pathway inhibition alters the tumor growth mode, revealing that tumor-stroma crosstalk shapes tumor growth dynamics and clonal architecture.
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•Marker-free lineage tracing and modeling reveal pancreatic cancer growth dynamics•Clonogenicity of pancreatic cancer cells is fully defined by the microenvironment•Stromal Hh inhibition impacts on clonal dynamics, but not pancreatic tumor growth
Lodestijn et al. employ marker-free lineage tracing in pancreatic cancer xenograft models to demonstrate that clonogenic capacity of tumor cells is fully defined by the microenvironment and not by tumor-cell-intrinsic features. Consequently, targeting the stroma using Hedgehog inhibition alters clonal dynamics but does not limit tumor growth.
Pancreatic ductal adenocarcinoma (PDAC) is marked by an abundant stromal deposition. This stroma is suspected to harbor both tumor‐promoting and tumor‐suppressing properties. This is underscored by ...the disappointing results of stroma targeting in clinical studies. Given the complexity of tumor–stroma interaction in PDAC, there is a need to identify the stromal proteins that are predominantly tumor‐promoting. One possible candidate is SPOCK1 that we previously identified in a screening effort in PDAC. We extensively mined PDAC gene expression datasets, and used species‐specific transcript analysis in mixed‐species models for PDAC to study the patterns and driver mechanisms of SPOCK1 expression in PDAC. Advanced organotypic coculture models with primary patient‐derived tumor cells were used to further characterize the function of this protein. We found SPOCK1 expression to be predominantly stromal. Expression of SPOCK1 was associated with poor disease outcome. Coculture and ligand stimulation experiments revealed that SPOCK1 is expressed in response to tumor cell‐derived transforming growth factor‐beta. Functional assessment in cocultures demonstrated that SPOCK1 strongly affects the composition of the extracellular collagen matrix and by doing so, enables invasive tumor cell growth in PDAC. By defining the expression pattern and functional properties of SPOCK1 in pancreatic cancer, we have identified a stromal mediator of extracellular matrix remodeling that indirectly affects the aggressive behavior of PDAC cells. The recognition that stromal proteins actively contribute to the protumorigenic remodeling of the tumor microenvironment should aid the design of future clinical studies to target specific stromal targets.
Stromal SPOCK1 is a mediator of extracellular matrix remodeling, and it indirectly aids the aggressive growth of pancreatic cancer cells. The recognition that stromal proteins actively contribute to the protumorigenic remodeling of the tumor microenvironment should aid the design of future clinical studies to target specific stromal targets.
Recently it has been recognized that stromal markers could be used as a clinically relevant biomarker for therapy response and prognosis. Here, we report on a serum marker for stromal activation, A ...Disintegrin and Metalloprotease 12 (ADAM12) in colorectal cancer (CRC).
Using gene expression databases we investigated ADAM12 expression in CRC and delineated the source of ADAM12 expression. The clinical value of ADAM12 was retrospectively assessed in the CAIRO2 trial in metastatic CRC with 235 patients (31% of total cohort), and an independent rectal cancer cohort (n = 20).
ADAM12 is expressed by activated CRC associated fibroblasts. In the CAIRO2 trial cohort, ADAM12 serum levels were prognostic (ADAM12 low versus ADAM12 high; median OS 25.3 vs. 17.1 months, HR 1.48 95% CI 1.11-1.96, P = 0.007). The prognostic potential was specifically high for metastatic rectal cancer (HR 1.78 95% CI 1.06-3.00, P = 0.030) and mesenchymal subtype tumors (HR 2.12 95% CI 1.25-3.60, P = 0.004). ADAM12 also showed potential for predicting recurrence in an exploratory analysis of non-metastatic rectal cancers.
Here we describe a non-invasive marker for activated stroma in CRC which associates with poor outcome, especially for primary cancers located in the rectum.
The analysis of peripheral blood mononuclear cells (PBMCs) by flow cytometry holds promise as a platform for immune checkpoint inhibition (ICI) biomarker identification. Our aim was to characterize ...the systemic immune compartment in resectable esophageal adenocarcinoma patients treated with neoadjuvant ICI therapy. In total, 24 patients treated with neoadjuvant chemoradiotherapy (nCRT) and anti-PD-L1 (atezolizumab) from the PERFECT study (NCT03087864) were included and 26 patients from a previously published nCRT cohort. Blood samples were collected at baseline, on-treatment, before and after surgery. Response groups for comparison were defined as pathological complete responders (pCR) or patients with pathological residual disease (non-pCR). Based on multicolor flow cytometry of PBMCs, an immunosuppressive phenotype was observed in the non-pCR group of the PERFECT cohort, characterized by a higher percentage of regulatory T cells (Tregs), intermediate monocytes, and a lower percentage of type-2 conventional dendritic cells. A further increase in activated Tregs was observed in non-pCR patients on-treatment. These findings were not associated with a poor response in the nCRT cohort. At baseline, immunosuppressive cytokines were elevated in the non-pCR group of the PERFECT study. The suppressive subsets correlated at baseline with a Wnt/β-Catenin gene expression signature and on-treatment with epithelial-mesenchymal transition and angiogenesis signatures from tumor biopsies. After surgery monocyte activation (CD40), low CD8+Ki67+ T cell rates, and the enrichment of CD206+ monocytes were related to early recurrence. These findings highlight systemic barriers to effective ICI and the need for optimized treatment regimens.