Photoimmunotherapy retains its anti-tumor efficacy with increasing stromal content in heterotypic pancreatic cancer spheroids

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease characterized by increased levels of desmoplasia that contributes to reduced drug delivery and poor treatment outcomes. In PDAC, the stromal content can account for up to 90% of the total tumor volume. The complex interplay between stromal components, including pancreatic cancer associated fibroblasts (PCAFs), and PDAC cells in the tumor microenvironment (TME) have a significant impact on prognoses and thus needs to be recapitulated in vitro when evaluating various treatment strategies. This study is a systematic evaluation of photodynamic therapy (PDT) in 3D heterotypic coculture models of PDAC with varying ratios of patient derived PCAFs that simulate heterogenous PDAC tumors with increasing stromal content. The efficacy of antibody-targeted PDT (photoimmunotherapy; PIT) using cetuximab photoimmunoconjugates (PICs) of benzoporphyrin derivative (BPD) is contrasted with that of liposomal BPD (Visudyne), which is currently in PDT clinical trials for PDAC. We demonstrate that both Visudyne-PDT and PIT were effective in heterotypic PDAC 3D spheroids with a low stromal content. However, as the stromal content increases above 50% in the 3D spheroids, the efficacy of Visudyne-PDT is reduced by up to 10-fold, while PIT retains its efficacy. PIT was found to be 10-fold, 19-fold and 14-fold more phototoxic in spheroids with 50%, 75% and 90% PCAFs, respectively, as compared to Visudyne-PDT. This marked difference in efficacy is attributed to the ability of PICs to penetrate and distribute within spheroids with a higher stromal content, whereas Visudyne is restricted to the spheroid periphery. This study thus demonstrates how the stromal content in PDAC spheroids directly impacts their responsiveness to PDT and proposes PIT to be a highly suited treatment option for desmoplastic tumors with particularly high degrees of stromal content.

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Novel 3D µtissues Mimicking the Fibrotic Stroma in Pancreatic Cancer to Study Cellular Interactions and Stroma-Modulating Therapeutics

Cancers ◽

10.3390/cancers13195006 ◽

2021 ◽

Vol 13 (19) ◽

pp. 5006

Author(s):

Kunal P. Pednekar ◽

Marcel A. Heinrich ◽

Joop van Baarlen ◽

Jai Prakash

Keyword(s):

Pancreatic Cancer ◽

Tumor Cells ◽

Treatment Options ◽

Treatment Strategies ◽

Collagen Gel ◽

Current Treatment ◽

Ductal Adenocarcinoma ◽

Tumor Type ◽

Cellular Interactions

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive tumor type with low patient survival due to the low efficacy of current treatment options. Cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TME) create a dense fibrotic environment around the tumor cells, preventing therapies from reaching their target. Novel 3D in vitro models are needed that mimic this fibrotic barrier for the development of therapies in a biologically relevant environment. Here, novel PDAC microtissues (µtissues) consisting of pancreatic cancer cell core surrounded by a CAF-laden collagen gel are presented, that is based on the cells own contractility to form a hard-to-penetrate barrier. The contraction of CAFs is demonstrated facilitating the embedding of tumor cells in the center of the µtissue as observed in patients. The µtissues displayed a PDAC-relevant gene expression by comparing their gene profile with transcriptomic patient data. Furthermore, the CAF-dependent proliferation of cancer cells is presented, as well as the suitability of the µtissues to serve as a platform for the screening of CAF-modulating therapies in combination with other (nano)therapies. It is envisioned that these PDAC µtissues can serve as a high-throughput platform for studying cellular interactions in PDAC and for evaluating different treatment strategies in the future.

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Synergistic Interactions between GW8510 and Gemcitabine in an In Vitro Model of Pancreatic Cancer

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520621999210104201553 ◽

2021 ◽

Vol 21 ◽

Author(s):

Duygu Gencalp ◽

Sevcan Atay ◽

Hikmet H. Aydin ◽

Handan Ak

Keyword(s):

Cell Cycle ◽

Pancreatic Cancer ◽

Cell Viability ◽

Control Cell ◽

Survival Rates ◽

Treatment Strategies ◽

Ductal Adenocarcinoma ◽

Viability Analysis ◽

Protein Levels

Background: One of the main reasons for the poor survival rates of pancreatic cancer patients is the development of gemcitabine resistance, indicating that novel treatment strategies that have the ability to improve gemcitabine sensitivity are in need to combat this devastating disease. Methods: TCGA PAAD data was used to determine the clinicopathological significance of high RRM2 (Ribonucleotide reductase subunit M2) expression for pancreatic ductal adenocarcinoma (PDAC). The effects of GW8510 and gemcitabine on PANC-1 cell viability were determined using WST-8 assay. The potential synergistic interaction between GW8510 and gemcitabine was evaluated by the combination index (CI) analysis. The effects of GW8510 treatment on apoptosis, cell cycle, and cell migration, either in combination with gemcitabine or alone, were investigated. The effect of GW8510 on RRM2 protein levels was evaluated using ELISA assay. Results: RRM2 is significantly over-expressed in PDAC compared to healthy pancreatic tissues (p <0.0001). RRM2 mRNA expression was found to be significantly corralated with the overall survival rate of patients (HR=2.17 [1.44-3.27], p=0.00016) and the pathological stages of the disease (p=0.0054). GW8510 significantly decreased the RRM2 protein levels compared to the control. Cell viability analysis showed that GW8510 has a similar effect to gemcitabine in inhibiting PANC-1 cell viability. GW8510 was found to synergize with gemcitabine to inhibit PANC-1 cell viability and migration. However, the effects of GW8510 on PANC-1 cells could not be explained by induction of apoptosis or cell cycle arrest. Conclusion: Targeting RRM2 using GW8510 may have the potential to increase gemcitabine sensitivity in pancreatic cancer.

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Immune Cell Modulation of the Extracellular Matrix Contributes to the Pathogenesis of Pancreatic Cancer

Biomolecules ◽

10.3390/biom11060901 ◽

2021 ◽

Vol 11 (6) ◽

pp. 901

Author(s):

Ramiz S. Ahmad ◽

Timothy D. Eubank ◽

Slawomir Lukomski ◽

Brian A. Boone

Keyword(s):

Pancreatic Cancer ◽

Extracellular Matrix ◽

Immune Cells ◽

Immune Cell ◽

Treatment Strategies ◽

Stellate Cells ◽

Pancreatic Stellate Cells ◽

Ductal Adenocarcinoma ◽

Cellular Mechanisms ◽

Novel Treatment Strategies

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with a five-year survival rate of only 9%. PDAC is characterized by a dense, fibrotic stroma composed of extracellular matrix (ECM) proteins. This desmoplastic stroma is a hallmark of PDAC, representing a significant physical barrier that is immunosuppressive and obstructs penetration of cytotoxic chemotherapy agents into the tumor microenvironment (TME). Additionally, dense ECM promotes hypoxia, making tumor cells refractive to radiation therapy and alters their metabolism, thereby supporting proliferation and survival. In this review, we outline the significant contribution of fibrosis to the pathogenesis of pancreatic cancer, with a focus on the cross talk between immune cells and pancreatic stellate cells that contribute to ECM deposition. We emphasize the cellular mechanisms by which neutrophils and macrophages, specifically, modulate the ECM in favor of PDAC-progression. Furthermore, we investigate how activated stellate cells and ECM influence immune cells and promote immunosuppression in PDAC. Finally, we summarize therapeutic strategies that target the stroma and hinder immune cell promotion of fibrogenesis, which have unfortunately led to mixed results. An enhanced understanding of the complex interactions between the pancreatic tumor ECM and immune cells may uncover novel treatment strategies that are desperately needed for this devastating disease.

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NR5A2 transcriptional activation by BRD4 promotes pancreatic cancer progression by upregulating GDF15

Cell Death Discovery ◽

10.1038/s41420-021-00462-8 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Feng Guo ◽

Yingke Zhou ◽

Hui Guo ◽

Dianyun Ren ◽

Xin Jin ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cancer Cells ◽

Cancer Progression ◽

Transcriptional Activation ◽

Ductal Adenocarcinoma ◽

Pancreatic Cancer Cells ◽

Gene Sets ◽

And Migration

AbstractNR5A2 is a transcription factor regulating the expression of various oncogenes. However, the role of NR5A2 and the specific regulatory mechanism of NR5A2 in pancreatic ductal adenocarcinoma (PDAC) are not thoroughly studied. In our study, Western blotting, real-time PCR, and immunohistochemistry were conducted to assess the expression levels of different molecules. Wound-healing, MTS, colony formation, and transwell assays were employed to evaluate the malignant potential of pancreatic cancer cells. We demonstrated that NR5A2 acted as a negative prognostic biomarker in PDAC. NR5A2 silencing inhibited the proliferation and migration abilities of pancreatic cancer cells in vitro and in vivo. While NR5A2 overexpression markedly promoted both events in vitro. We further identified that NR5A2 was transcriptionally upregulated by BRD4 in pancreatic cancer cells and this was confirmed by Chromatin immunoprecipitation (ChIP) and ChIP-qPCR. Besides, transcriptome RNA sequencing (RNA-Seq) was performed to explore the cancer-promoting effects of NR5A2, we found that GDF15 is a component of multiple down-regulated tumor-promoting gene sets after NR5A2 was silenced. Next, we showed that NR5A2 enhanced the malignancy of pancreatic cancer cells by inducing the transcription of GDF15. Collectively, our findings suggest that NR5A2 expression is induced by BRD4. In turn, NR5A2 activates the transcription of GDF15, promoting pancreatic cancer progression. Therefore, NR5A2 and GDF15 could be promising therapeutic targets in pancreatic cancer.

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Hyperglycemia Promotes Pancreatic Cancer Initiation and Progression by Activating the Wnt/β-Catenin Signaling Pathway

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520621666210201095613 ◽

2021 ◽

Vol 21 ◽

Author(s):

Huiming Chen ◽

Junfeng Zhao ◽

Ningning Jiang ◽

Zheng Wang ◽

Chang Liu

Keyword(s):

Pancreatic Cancer ◽

Signaling Pathway ◽

Precancerous Lesions ◽

Clinical Specimen ◽

Ductal Adenocarcinoma ◽

Dependent Manner ◽

Pancreatic Cancer Cells ◽

Cancer Initiation

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal diseases, with a 5-year survival rate of less than 10% because of the limited knowledge of tumor-promoting factors and their underlying mechanism. Diabetes mellitus (DM) and hyperglycemia are risk factors for many cancers, including PDAC, that modulate multiple downstream signaling pathways, such as the wingless/integrated (Wnt)/β-catenin signaling pathway. However, whether hyperglycemia promotes PDAC initiation and progression by activating the Wnt/β-catenin signaling pathway remains unclear. Methods: In this study, we used bioinformatics analysis and clinical specimen analysis to evaluate the activation states of the Wnt/βcatenin signaling pathway. In addition, colony formation assays, Transwell assays and wound-healing assays were used to evaluate the malignant biological behaviors of pancreatic cancer cells (PCs) under hyperglycemic conditions. To describe the effects of hyperglycemia and the Wnt/β-catenin signaling pathway on the initiation of PDAC, we used pancreatitis-driven pancreatic cancer initiation models in vivo and pancreatic acinar cell 3-dimensional culture in vitro. Results: Wnt/β-catenin signaling pathway-related molecules were overexpressed in PDAC tissues/cells and correlated with poor prognosis in PDAC patients. In addition, hyperglycemia exacerbated the abnormal activation of β-catenin in PDAC and enhanced the malignant biological behaviors of PCs in a Wnt/β-catenin signaling pathway-dependent manner. Indeed, hyperglycemia accelerated the formation of pancreatic precancerous lesions by activating the Wnt/β-catenin signaling pathway in vivo and in vitro. Conclusion: Hyperglycemia promotes pancreatic cancer initiation and progression by activating the Wnt/β-catenin signaling pathway.

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KIF4A Regulates the Progression of Pancreatic Ductal Adenocarcinoma through Proliferation and Invasion

BioMed Research International ◽

10.1155/2021/8249293 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Jing Chen ◽

Cui-Cui Zhao ◽

Fei-Ran Chen ◽

Guo-Wei Feng ◽

Fei Luo ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cell Proliferation ◽

Pancreatic Ductal Adenocarcinoma ◽

Disease Free Survival ◽

High Expression ◽

Ductal Adenocarcinoma ◽

Migration And Invasion

Background. Pancreatic cancer is a malignant tumor of the digestive tract, which is difficult to diagnose and treat due to bad early diagnosis. We aimed to explore the role of kinesin superfamily 4A (KIF4A) in pancreatic ductal adenocarcinoma (PDAC). Methods. We first used the bioinformatic website to screen the data of pancreatic cancer in TCGA, and KIF4A protein was detected among the 86 specimens of patients in our hospital combined with clinic-pathological characteristics and survival analysis. KIF4A loss-expression cell lines were established by RNA interference (RNAi). In addition, we performed in vitro cell assays to detect the changes in cell proliferation, migration, and invasion. The proteins involved in the proliferation and metastasis of cancer cells were also detected by western blot. The above results could be proved in vivo. Further, the correlation between KIF4A and CDC5L was analyzed by TCGA and IHC data. Results. We first found a high expression of KIF4A in pancreatic cancer, suggesting a role of KIF4A in the development of pancreatic cancer. KIF4A was found to be differentially expressed ( P < 0.05 ) among the 86 specimens of patients in our hospital and was significantly associated with PDAC TNM stages and tumor size. High KIF4A expression also significantly worsened overall survival (OS) and disease-free survival rate (DFS) ( P < 0.05 , respectively). In addition, cell proliferation, migration, and invasion were inhibited by the KIF4A-shRNA group compared with the control ( P < 0.05 , respectively). In the end, knockdown of KIF4A could inhibit tumor development and metastasis in vivo. Further, the positive correlation between KIF4A and CDC5L existed, and KIF4A might promote pancreatic cancer proliferation by affecting CDC5L expression. Conclusion. In conclusion, the high expression level of KIF4A in PDAC was closely related to poor clinical and pathological status, lymphatic metastasis, and vascular invasion. KIF4A might be involved in promoting the development of PDAC in vitro and in vivo, which might be a new therapeutic target of PDAC.

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Adjuvant and Neoadjuvant Therapy for Pancreatic Adenocarcinoma

10.2310/7800.16076 ◽

2017 ◽

Author(s):

Gregory C Wilson ◽

Brent T Xia ◽

Syed A Ahmed

Keyword(s):

Pancreatic Cancer ◽

Adjuvant Therapy ◽

Neoadjuvant Therapy ◽

Pancreatic Adenocarcinoma ◽

Locally Advanced ◽

Neoadjuvant Treatment ◽

Advanced Pancreatic Cancer ◽

Treatment Strategies ◽

Ductal Adenocarcinoma ◽

Borderline Resectable

Despite decades of advancement and research into the multimodal care of pancreatic cancer, mortality after the diagnosis of pancreatic ductal adenocarcinoma remains grim. The role of adjuvant therapy following surgical resection has been well established in the literature. However, adjuvant therapy is imperfect, and outside of a clinical trial, there are high rates of omission or delayed initiation of therapy. Neoadjuvant treatment strategies continue to be explored in the management of resectable, borderline-resectable, and locally advanced unresectable pancreatic adenocarcinoma. With improved resection rates and the possibility for tumor downstaging, neoadjuvant therapy has become standard for patients with borderline-resectable and locally advanced unresectable tumors. Additional benefits of neoadjuvant therapy in the treatment of resectable tumors include improved completion rates of systemic therapy and R0 resection rates. Future clinical trials, including the use of novel treatment agents and combination treatment strategies in both neoadjuvant and adjuvant regimens, will add value to the treatment of pancreatic adenocarcinoma. Key words: adjuvant therapy, borderline-resectable pancreatic cancer, locally advanced pancreatic cancer, neoadjuvant therapy, pancreatic adenocarcinoma, resectable disease

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Missing links — epigenetic regulators of the pancreatic cancer–associated inflammation

Clinical Science ◽

10.1042/cs20210181 ◽

2021 ◽

Vol 135 (10) ◽

pp. 1289-1293

Author(s):

Gregor Werba ◽

Tamas A. Gonda

Keyword(s):

Pancreatic Cancer ◽

Noncoding Rna ◽

Current Knowledge ◽

Treatment Strategies ◽

Therapeutic Interventions ◽

Ductal Adenocarcinoma ◽

Gastrointestinal Cancers ◽

Novel Treatment ◽

Epigenetic Regulator ◽

Novel Treatment Strategies

Abstract Pancreatic ductal adenocarcinoma (PDAC) features a hostile tumor microenvironment (TME) that renders it remarkably resistant to most therapeutic interventions. Consequently, survival remains among the poorest compared with other gastrointestinal cancers. Concerted efforts are underway to decipher the complex PDAC TME, break down barriers to efficacious therapies and identify novel treatment strategies. In the recent Clinical Science, Li and colleagues identify the long noncoding RNA KLHDC7B-DT as a crucial epigenetic regulator of IL-6 transcription in PDAC and illustrate its potent influences on the pancreatic TME. In this commentary, we introduce epigenetics in pancreatic cancer and put the findings by Li et al. in context with current knowledge.

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Organotypic Culture of Acinar Cells for the Study of Pancreatic Cancer Initiation

Cancers ◽

10.3390/cancers12092606 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2606

Author(s):

Carlotta Paoli ◽

Alessandro Carrer

Keyword(s):

Pancreatic Cancer ◽

Ex Vivo ◽

Acinar Cells ◽

Lineage Tracing ◽

Metabolic Reprogramming ◽

Pancreatic Acinar Cells ◽

Ductal Adenocarcinoma ◽

Molecular Features ◽

The Impact

The carcinogenesis of pancreatic ductal adenocarcinoma (PDA) progresses according to multi-step evolution, whereby the disease acquires increasingly aggressive pathological features. On the other hand, disease inception is poorly investigated. Decoding the cascade of events that leads to oncogenic transformation is crucial to design strategies for early diagnosis as well as to tackle tumor onset. Lineage-tracing experiments demonstrated that pancreatic cancerous lesions originate from acinar cells, a highly specialized cell type in the pancreatic epithelium. Primary acinar cells can survive in vitro as organoid-like 3D spheroids, which can transdifferentiate into cells with a clear ductal morphology in response to different cell- and non-cell-autonomous stimuli. This event, termed acinar-to-ductal metaplasia, recapitulates the histological and molecular features of disease initiation. Here, we will discuss the isolation and culture of primary pancreatic acinar cells, providing a historical and technical perspective. The impact of pancreatic cancer research will also be debated. In particular, we will dissect the roles of transcriptional, epigenetic, and metabolic reprogramming for tumor initiation and we will show how that can be modeled using ex vivo acinar cell cultures. Finally, mechanisms of PDA initiation described using organotypical cultures will be reviewed.

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Conversion Surgery for Advanced Pancreatic Cancer

Journal of Clinical Medicine ◽

10.3390/jcm8111945 ◽

2019 ◽

Vol 8 (11) ◽

pp. 1945

Author(s):

Thomas Hank ◽

Oliver Strobel

Keyword(s):

Pancreatic Cancer ◽

Locally Advanced ◽

Palliative Therapy ◽

Advanced Pancreatic Cancer ◽

Treatment Strategies ◽

Ductal Adenocarcinoma ◽

Conversion Surgery ◽

Radiological Criteria ◽

Intention To Treat ◽

Conversion Rates

While primarily unresectable locally advanced pancreatic cancer (LAPC) used to be an indication for palliative therapy, a strategy of neoadjuvant therapy (NAT) and conversion surgery is being increasingly used after more effective chemotherapy regimens have become available for pancreatic ductal adenocarcinoma. While high-level evidence from prospective studies is still sparse, several large retrospective studies have recently reported their experience with NAT and conversion surgery for LAPC. This review aims to provide a current overview about different NAT regimens, conversion rates, survival outcomes and determinants of post-resection outcomes, as well as surgical strategies in the context of conversion surgery after NAT. FOLFIRINOX is the predominant regimen used and associated with the highest reported conversion rates. Conversion rates considerably vary between less than 5% and more than half of the study population with heterogeneous long-term outcomes, owing to a lack of intention-to-treat analyses in most studies and a high heterogeneity in resectability criteria, treatment strategies, and reporting among studies. Since radiological criteria of local resectability are no longer applicable after NAT, patients without progressive disease should undergo surgical exploration. Surgery after NAT has to be aimed at local radicality around the peripancreatic vessels and should be performed in expert centers. Future studies in this rapidly evolving field need to be prospective, analyze intention-to-treat populations, report stringent and objective inclusion criteria and criteria for resection. Innovative regimens for NAT in combination with a radical surgical approach hold high promise for patients with LAPC in the future.

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