Stromal biology and therapy in pancreatic cancer: a changing paradigm

Polychromatic Polarization Microscopy Differentiates Collagen Fiber Signatures in Benign Pancreatic Tissue and Pancreatic Ductal Adenocarcinoma

The orientation of collagen fibers in relation to malignant epithelium is known to carry prognostic information in a variety of tissues. The data are strongest for breast and pancreatic ductal adenocarcinoma (PDAC). However, the information inherent in collagen fiber topology in malignant tissues remains untapped in daily surgical pathology practice, largely because collagen fibers within areas of desmoplasia cannot be resolved with standard diagnostic microscopy. The methodologies used to visualize collagen fiber orientation are either of insufficient resolution to consistently capture collagen fiber topology or require resources in time and money that do not fit into the daily surgical pathology workflow. Polychromatic polarization microscopy (PPM) has the potential to bring collagen topology to the attention of pathologists during their routine work. It has been demonstrated to be equivalent to the gold standard methodology used to research collagen, second harmonic generation (SHG). We use PPM to visualize and describe the differences in collagen topology in normal pancreas, chronic pancreatitis, and PDAC with a standard microscope, using H&E-stained sections. In the process, we propose a lexicon with which to describe the morphologic characteristics of collagen in benign and malignant pancreatic tissue.

Engineered a Gemcitabine Nano-Prodrug Targeting Desmoplastic Pancreatic Tumor with Dual Enhancement of Penetration Dynamics

The desmoplastic nature characterized by dense tissue and poor vascular conditions in pancreatic cancer (PDAC) poses a significant barrier to effective chemotherapy. Targeting the extracellular matrix and reducing desmoplasia in the tumor microenvironment is a rational approach to improve the penetration and efficacy of gemcitabine (GEM) in PDAC. Herein, a small molecular self-assembly nano-prodrug is developed for the "three-in-one" co-delivery of GEM chemotherapeutics, all-trans retinoic acid (ATRA), and nitric oxide (NO) donors, decorated with PDAC-homing targeting peptide. Stimulated by the PDAC microenvironment, the nano-prodrug releases ATRA that quiesces activated pancreatic stellate cells to alleviate stromal desmoplasia. Simultaneously, it generates abundant NO to induce a vasodilatory effect as well as a "nanomotor" effect. This combinational nano-prodrug delivery strategy, with a dual enhancement of drug penetration dynamics, effectively improves the distribution and bioavailability of the co-delivered GEM into the deep and dense pancreatic tumor tissue, which leads to significant amplification of tumor growth inhibition in different PDAC mouse models.

Pancreatic cancer: failures and hopes-a review of new promising treatment approaches

Pancreatic cancer is a challenging disease with limited treatment options and a high mortality rate. Just few therapy advances have been made in recent years. Tumor microenvironment, immunosuppressive features and mutational status represent important obstacles in the improvement of survival outcomes. Up to now, first-line therapy did achieve a median overall survival of less than 12 months and this discouraging data lead clinicians all over the world to focus their efforts on various fields of investigation: 1) sequential cycling of different systemic therapy in order to overcome mechanisms of resistance; 2) discovery of new predictive bio-markers, in order to target specific patient population; 3) combination treatment, in order to modulate the tumor microenvironment of pancreatic cancer; 4) new modalities of the delivery of drugs in order to pass the physical barrier of desmoplasia and tumor stroma. This review shows future directions of treatment strategies in advanced pancreatic cancer through a deep analysis of these recent macro areas of research.

Targeting the NPY/NPY1R signaling axis in mutant p53-dependent pancreatic cancer impairs metastasis

Pancreatic cancer (PC) is a highly metastatic malignancy. More than 80% of patients with PC present with advanced-stage disease, preventing potentially curative surgery. The neuropeptide Y (NPY) system, best known for its role in controlling energy homeostasis, has also been shown to promote tumorigenesis in a range of cancer types, but its role in PC has yet to be explored. We show that expression of NPY and NPY1R are up-regulated in mouse PC models and human patients with PC. Moreover, using the genetically engineered, autochthonous KPR172HC mouse model of PC, we demonstrate that pancreas-specific and whole-body knockout of Npy1r significantly decreases metastasis to the liver. We identify that treatment with the NPY1R antagonist BIBO3304 significantly reduces KPR172HC migratory capacity on cell-derived matrices. Pharmacological NPY1R inhibition in an intrasplenic model of PC metastasis recapitulated the results of our genetic studies, with BIBO3304 significantly decreasing liver metastasis. Together, our results reveal that NPY/NPY1R signaling is a previously unidentified antimetastatic target in PC.

CDCA7 enhances STAT3 transcriptional activity to regulate aerobic glycolysis and promote pancreatic cancer progression and gemcitabine resistance

Cell division cycle associated 7 (CDCA7) plays a role in various malignancies, especially pancreatic cancer (PC). However, its expression pattern and functional significance in PC require further research. Therefore, this study aimed to investigate CDCA7 expression levels and biological functions in PC using in vitro and in vivo experiments. Western blotting, immunohistochemistry, and real-time polymerase chain reaction were performed to detect CDCA7 expression in PC cells and tissues. Additionally, the biological functions of CDCA7 were assessed using cell proliferation, wound healing, and Transwell assays. CDCA7 overexpression promoted PC cell proliferation, migration, and invasion, and increased resistance to the chemotherapy drug gemcitabine, possibly through enhanced aerobic glycolysis. Additionally, immunoprecipitation assay showed that CDCA7 interacted with STAT3 protein and affected the transcriptional regulation of hexokinase 2. Conclusively, targeting CDCA7 might be a promising therapeutic strategy to increase gemcitabine sensitivity by inhibiting glycolysis in PC cells.

Bystander Expression of Atypical Chemokine Receptor 2 Protects T Cells from Chemoattraction towards Cancer-Associated Fibroblasts

Atypical chemokine receptors (ACKRs) are a subclass of chemokine receptors that internalise and degrade chemokines instead of eliciting chemotaxis. Scavenging by ACKRs reduces the local bioavailability of chemokines and can thus reshape chemokine gradients that direct leukocyte trafficking during inflammation and anticancer responses. In pancreatic ductal adenocarcinoma (PDAC), chemokine axes, such as CXCL12-CXCR4, are co-opted by cancer-associated fibroblasts (CAFs) for tumour growth and escape, and immunosuppression. Here, we explore the use of ACKRs to reshape chemokine gradients within the PDAC tumour microenvironment. ACKR2, previously only known to scavenge inflammatory CC chemokines, was recently shown to be able to interact with CXCL10 and CXCL14. Here, using a chemokine binding assay and cytometric bead arrays, we reveal that ACKR2 scavenges additional CXC chemokines CXCL12 and CXCL1. ACKR2 scavenges CXCL12 with reduced efficiency compared to ACKR3, previously reported to bind CXCL12. Finally, we demonstrate that the overexpression of ACKR2 on bystander cells protects primary murine cytotoxic T lymphocytes from PDAC CAF-mediated chemoattraction. These findings reveal new CXC chemokine ligands of ACKR2 and indicate that ACKR overexpression may protect T cells from misdirection by CAFs.

Targeting of the G9a, DNMT1 and UHRF1 epigenetic complex as an effective strategy against pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with limited treatment options and a poor prognosis. The critical role of epigenetic alterations such as changes in DNA methylation, histones modifications, and chromatin remodeling, in pancreatic tumors progression is becoming increasingly recognized. Moreover, in PDAC these aberrant epigenetic mechanisms can also limit therapy efficacy. This study aimed to investigate the expression and prognostic significance of a key epigenetic complex encompassing DNA methyltransferase-1 (DNMT1), the histone methyltransferase G9a, and the scaffold protein UHRF1 in PDAC. We also evaluated the therapeutic potential of an innovative inhibitor targeting these epigenetic effectors.

METHODS

Immunohistochemical analysis of DNMT1, G9a, and UHRF1 expression was conducted in human PDAC tissue samples. Staining was semi-quantitatively scored, and overexpression was defined as moderate to strong positivity. The prognostic impact was assessed by correlating protein expression with patient survival. The antitumoral effects of the dual DNMT1-G9a inhibitor CM272 were tested in PDAC cell lines, followed by transcriptomic analyses to identify underlying mechanisms. The in vivo antitumoral efficacy of CM272 was evaluated in PDAC xenograft and syngeneic mouse models, both alone and in combination with anti-PD1 immunotherapy.

RESULTS

DNMT1, G9a, and UHRF1 were significantly overexpressed in PDAC cells and stroma compared to normal pancreatic tissues. Simultaneous overexpression of the three proteins was associated with significantly reduced survival in resected PDAC patients. CM272 exhibited potent antiproliferative activity in PDAC cell lines, inducing apoptosis and altering key metabolic and cell cycle-related genes. CM272 also enhanced chemotherapy sensitivity and significantly inhibited tumor growth in vivo without detectable toxicity. Combination of CM272 with anti-PD1 therapy further improved antitumor responses and immune cell infiltration, particularly CD4 + and CD8 + T cells.

CONCLUSIONS

The combined overexpression of DNMT1, G9a, and UHRF1 in PDAC is a strong predictor of poor prognosis. CM272, by targeting this epigenetic complex, shows promising therapeutic potential by inducing apoptosis, reprogramming metabolic pathways, and enhancing immune responses. The combination of CM272 with immunotherapy offers a novel, effective treatment strategy for PDAC.

Chemoresistance in Pancreatic Cancer: The Role of Adipose-Derived Mesenchymal Stem Cells and Key Resistance Genes

Drug resistance is a significant challenge in pancreatic ductal adenocarcinoma (PDAC), where stromal elements such as adipose-derived mesenchymal stem cells (ASCs) contribute to a chemoresistant tumor microenvironment (TME). This study explored the effects of oxaliplatin (OXP) and 5-fluorouracil (5-FU) on PDAC cells (Capan-1) and ASCs to investigate the mechanisms of chemoresistance. While OXP and 5-FU reduced Capan-1 viability in a dose- and time-dependent manner, ASCs demonstrated high resistance, maintaining > 90% viability even at cytotoxic doses. Transcriptomic analyses revealed OXP-induced transcriptional reprogramming in ASCs, with over 7000 differentially expressed genes, highlighting the pathways related to DNA damage response, cell cycle regulation, and stress-related signaling. In contrast, 5-FU elicited limited transcriptional changes, affecting only 192 genes. Cytokine proteome profiling revealed that OXP-treated ASCs significantly influenced the tumor microenvironment by promoting immune evasion (via IL-4, GM-CSF, IP-10, and GROα) and driving extracellular matrix remodeling (through EMMPRIN and DPPIV). In contrast, 5-FU induced comparatively weaker effects, primarily limited to hypoxia-related pathways. Although OXP reduced angiogenic factors, it paradoxically activated pro-survival pathways, thereby enhancing ASC-mediated tumor support. These findings underscore ASCs as modulators of chemoresistance via secretome alterations and stress adaptation. Therefore, future strategies should prioritize the precise targeting of tumor cells while also focusing on the development of personalized treatments to achieve durable therapeutic responses in PDAC.

Plasticity and Tumor Microenvironment in Pancreatic Cancer: Genetic, Metabolic, and Immune Perspectives

Cancer has long been believed to be a genetic disease caused by the accumulation of mutations in key genes involved in cellular processes. However, recent advances in sequencing technology have demonstrated that cells with cancer driver mutations are also present in normal tissues in response to aging, environmental damage, and chronic inflammation, suggesting that not only intrinsic factors within cancer cells, but also environmental alterations are important key factors in cancer development and progression. Pancreatic cancer tissue is mostly comprised of stromal cells and immune cells. The desmoplasmic microenvironment characteristic of pancreatic cancer is hypoxic and hypotrophic. Pancreatic cancer cells may adapt to this environment by rewiring their metabolism through epigenomic changes, enhancing intrinsic plasticity, creating an acidic and immunosuppressive tumor microenvironment, and inducing noncancerous cells to become tumor-promoting. In addition, pancreatic cancer has often metastasized to local and distant sites by the time of diagnosis, suggesting that a similar mechanism is operating from the precancerous stage. Here, we review key recent findings on how pancreatic cancers acquire plasticity, undergo metabolic reprogramming, and promote immunosuppressive microenvironment formation during their evolution. Furthermore, we present the following two signaling pathways that we have identified: one based on the small G-protein ARF6 driven by KRAS/TP53 mutations, and the other based on the RNA-binding protein Arid5a mediated by inflammatory cytokines, which promote both metabolic reprogramming and immune evasion in pancreatic cancer. Finally, the striking diversity among pancreatic cancers in the relative importance of mutational burden and the tumor microenvironment, their clinical relevance, and the potential for novel therapeutic strategies will be discussed.

Dual rectification of metabolism abnormality in pancreatic cancer by a programmed nanomedicine

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive and lethal malignancy characterized by dysregulated energy and stromal metabolism. It is strongly supported by activated pancreatic stellate cells (PSC) which drive excessive desmoplasia and tumor growth via metabolic crosstalk. Herein, a programmed nanosystem is designed to dual rectify the metabolism abnormalities of the PDAC cells, which overexpress glucose transporter 1(GLUT1) and CD71, and the PSC for oncotherapy. The nanosystem is based on a tumor microenvironment-responsive liposome encapsulating an NF-κB inhibitor (TPCA-1) and a CD71 aptamer-linked Glut1 siRNA. TPCA-1 reverses the activated PSC to quiescence, which hampers metabolic support of the PSC to PDAC cells and bolsters the PDAC cell-targeting delivery of the siRNA. Aerobic glycolysis and the following enhancement of oxidative phosphorylation are restrained by the nano-modulation so as to amplify anti-PDAC efficacy in an orthotopic xenograft mouse model, which implies more personalized PDAC treatment based on different energy metabolic profiles.

Upregulation of HSD11B1 promotes cortisol production and inhibits NK cell activation in pancreatic adenocarcinoma

Cortisol is a glucocorticoid hormone that has immunosuppressive function. Elevated basal cortisol levels are present in patients with some kinds of cancers, but its role in the microenvironment of pancreatic adenocarcinoma (PAAD) remains unclear. This study analyzed the expression of genes involved in cortisol generation by using high-throughput sequencing data from TCGA portal and found HSD11B1 was significantly upregulated in patients with PAAD. The correlations between HSD11B1 level and the expression of 23 immunosuppressive receptors were analyzed by Spearman's correlation analysis. The function of HSD11B1 was examined in primary NK cells and PAAD cell lines. The levels of cortisol in medium and cell lysates were detected by ELISA. In vitro killing assay was used to evaluate the cytotoxicity of NK cells. Cell surface levels of CD96, Tim-3, PD-1, TIGIT, CTLA-4, NKp46, NKp30, NKD2G and LFA-1A, and intracellular levels of CD107a and IFN-γ were examined by flow cytometry. We observed that patients with higher HSD11B1 level had shorter survival time. HSD11B1 is positively correlated with the mRNA levels of 11 immunosuppressive receptors in PAAD. Higher HSD11B1 level relates to reduced abundance of activated NK cells in the tumors. HSD11B1 overexpressed NK cells exhibit exhausted phenotype with increased cortisol production, reduced viability, and reduced cytotoxicity against cancer cells. Overexpression of HSD11B1 did not change the viability of tumor cells but upregulated cortisol production. Targeting HSD11B1 by a specific inhibitor improved the NK cells responsiveness. In conclusion, HSD11B1 is upregulated in patients with PAAD, and higher HSD11B1 level is related to poor prognosis. Upregulation of HSD11B1 in NK and tumor cells increased the production and secretion of cortisol and induces NK cell exhaustion.

Signal enhancement ratio of multi-phase contrast-enhanced MRI: an imaging biomarker for survival in pancreatic adenocarcinoma

OBJECTIVES

To evaluate signal enhancement ratio (SER) for tissue characterization and prognosis stratification in pancreatic adenocarcinoma (PDAC), with quantitative histopathological analysis (QHA) as the reference standard.

METHODS

This retrospective study included 277 PDAC patients who underwent multi-phase contrast-enhanced (CE) MRI and whole-slide imaging (WSI) from three centers (2015-2021). SER is defined as (SIlt - SIpre)/(SIea - SIpre), where SIpre, SIea, and SIlt represent the signal intensity of the tumor in pre-contrast, early-, and late post-contrast images, respectively. Deep-learning algorithms were implemented to quantify the stroma, epithelium, and lumen of PDAC on WSIs. Correlation, regression, and Bland-Altman analyses were utilized to investigate the associations between SER and QHA. The prognostic significance of SER on overall survival (OS) was evaluated using Cox regression analysis and Kaplan-Meier curves.

RESULTS

The internal dataset comprised 159 patients, which was further divided into training, validation, and internal test datasets (n = 60, 41, and 58, respectively). Sixty-five and 53 patients were included in two external test datasets. Excluding lumen, SER demonstrated significant correlations with stroma (r = 0.29-0.74, all p < 0.001) and epithelium (r = -0.23 to -0.71, all p < 0.001) across a wide post-injection time window (range, 25-300 s). Bland-Altman analysis revealed a small bias between SER and QHA for quantifying stroma/epithelium in individual training, validation (all within ± 2%), and three test datasets (all within ± 4%). Moreover, SER-predicted low stromal proportion was independently associated with worse OS (HR = 1.84 (1.17-2.91), p = 0.009) in training and validation datasets, which remained significant across three combined test datasets (HR = 1.73 (1.25-2.41), p = 0.001).

CONCLUSION

SER of multi-phase CE-MRI allows for tissue characterization and prognosis stratification in PDAC.

CLINICAL RELEVANCE STATEMENT

The signal enhancement ratio of multi-phase CE-MRI can serve as a novel imaging biomarker for characterizing tissue composition and holds the potential for improving patient stratification and therapy in PDAC.

KEY POINTS

Imaging biomarkers are needed to better characterize tumor tissue in pancreatic adenocarcinoma. Signal enhancement ratio (SER)-predicted stromal/epithelial proportion showed good agreement with histopathology measurements across three distinct centers. Signal enhancement ratio (SER)-predicted stromal proportion was demonstrated to be an independent prognostic factor for OS in PDAC.

Advances in tumor stroma-based targeted delivery

The tumor stroma plays a crucial role in tumor progression, and the interactions between the extracellular matrix, tumor cells, and stromal cells collectively influence tumor progression and the efficacy of therapeutic agents. Currently, utilizing components of the tumor stroma for drug delivery is a noteworthy strategy. A number of targeted drug delivery systems designed based on tumor stromal components are entering clinical trials. Therefore, this paper provides a thorough examination of the function of tumor stroma in the advancement of targeted drug delivery systems. One approach is to use tumor stromal components for targeted drug delivery, which includes certain stromal components possessing inherent targeting capabilities like HA, laminin, along with targeting stromal cells homologously. Another method entails directly focusing on tumor stromal components to reshape the tumor stroma and facilitate drug delivery. These drug delivery systems exhibit great potential in more effective cancer therapy strategies, such as precise targeting, enhanced penetration, improved safety profile, and biocompatibility. Ultimately, the deployment of these drug delivery systems can deepen our comprehension of tumor stroma and the advanced development of corresponding drug delivery systems.

Improving tumor microenvironment assessment in chip systems through next-generation technology integration

The tumor microenvironment (TME) comprises a diverse array of cells, both cancerous and non-cancerous, including stromal cells and immune cells. Complex interactions among these cells play a central role in driving cancer progression, impacting critical aspects such as tumor initiation, growth, invasion, response to therapy, and the development of drug resistance. While targeting the TME has emerged as a promising therapeutic strategy, there is a critical need for innovative approaches that accurately replicate its complex cellular and non-cellular interactions; the goal being to develop targeted, personalized therapies that can effectively elicit anti-cancer responses in patients. Microfluidic systems present notable advantages over conventional in vitro 2D co-culture models and in vivo animal models, as they more accurately mimic crucial features of the TME and enable precise, controlled examination of the dynamic interactions among multiple human cell types at any time point. Combining these models with next-generation technologies, such as bioprinting, single cell sequencing and real-time biosensing, is a crucial next step in the advancement of microfluidic models. This review aims to emphasize the importance of this integrated approach to further our understanding of the TME by showcasing current microfluidic model systems that integrate next-generation technologies to dissect cellular intra-tumoral interactions across different tumor types. Carefully unraveling the complexity of the TME by leveraging next generation technologies will be pivotal for developing targeted therapies that can effectively enhance robust anti-tumoral responses in patients and address the limitations of current treatment modalities.

Synergistic Effects of Matrix Biophysical Properties on Gastric Cancer Cell Behavior via Integrin-Mediated Cell-ECM Interactions

The biophysical properties of the extracellular matrix (ECM) play a pivotal role in modulating cancer progression via cell-ECM interactions. However, the biophysical properties specific to gastric cancer (GC) remain largely unexplored. Pertinently, GC ECM shows significantly heterogeneous metamorphoses, such as matrix stiffening and intricate restructuring. By combining collagen I and alginate, this study designs an in vitro biomimetic hydrogel platform to independently modulate matrix stiffness and structure across a physiological stiffness spectrum while preserving consistent collagen concentration and fiber topography. With this platform, this study assesses the impacts of matrix biophysical properties on cell proliferation, migration, invasion, and other pivotal dynamics of AGS. The findings spotlight a compelling interplay between matrix stiffness and structure, influencing both cellular responses and ECM remodeling. Furthermore, this investigation into the integrin/actin-collagen interplay reinforces the central role of integrins in mediating cell-ECM interactions, reciprocally sculpting cell conduct, and ECM adaptation. Collectively, this study reveals a previously unidentified role of ECM biophysical properties in GC malignant potential and provides insight into the bidirectional mechanical cell-ECM interactions, which may facilitate the development of novel therapeutic horizons.

Combining gemcitabine and MSC delivering soluble TRAIL to target pancreatic adenocarcinoma and its stroma

Pancreatic ductal adenocarcinoma (PDAC) still has a poor response to therapies, partly due to their cancer-associated fibroblasts (CAFs). Here, we investigate the synergistic impact of a combinatory approach between a known chemotherapy agent, such as gemcitabine (GEM), and gene-modified human mesenchymal stromal/stem cells (MSCs) secreting the pro-apoptotic soluble (s)TRAIL (sTRAIL MSCs) on both PDAC cells and CAFs. The combo significantly impacts on PDAC survival in 2D and 3D models. In orthotopic xenograft models, GEM and sTRAIL MSCs induce tumor architecture shredding with a reduction of CK7- and CK8/18-positive cancer cells and the abrogation of spleen metastases. A cytotoxic effect on primary human CAFs is also observed along with an alteration of their transcriptome and a reduction of the related desmoplasia. Collectively, we demonstrate a promising therapeutic profile of combining GEM and sTRAIL MSCs to target both tumoral and stromal compartments in PDAC.

Chemotherapy Assessment in Advanced Multicellular 3D Models of Pancreatic Cancer: Unravelling the Importance of Spatiotemporal Mimicry of the Tumor Microenvironment

Pancreatic ductal adenocarcinoma (PDAC) is a challenge for global health with very low survival rate and high therapeutic resistance. Hence, advanced preclinical models for treatment screening are of paramount importance. Herein, chemotherapeutic (gemcitabine) assessment on novel (polyurethane) scaffold-based spatially advanced 3D multicellular PDAC models is carried out. Through comprehensive image-based analysis at the protein level, and expression analysis at the mRNA level, the importance of stromal cells is confirmed, primarily activated stellate cells in the chemoresistance of PDAC cells within the models. Furthermore, it is demonstrated that, in addition to the presence of activated stellate cells, the spatial architecture of the scaffolds, i.e., segregation/compartmentalization of the cancer and stromal zones, affect the cellular evolution and is necessary for the development of chemoresistance. These results highlight that, further to multicellularity, mapping the tumor structure/architecture and zonal complexity in 3D cancer models is important for better mimicry of the in vivo therapeutic response.

Expression of gemcitabine metabolizing enzymes and stromal components reveal complexities of preclinical pancreatic cancer models for therapeutic testing

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) poorly responds to antineoplastic agents. Discrepancies between preclinical success and clinical failure of compounds has been a continuous challenge and major obstacle in PDAC research.

AIM

To investigate the association of the tumor microenvironment (TME) composition and gemcitabine metabolizing enzyme (GME) expression in vitro and several in vivo models.

METHODS

mRNA expression and protein levels of GME (cytosolic 5'-nucleotidase 1 A; NT5C1A, cytidine deaminase; CDA, deoxycytidine kinase; DCK), gemcitabine transporters (ENT1, ENT2, RRM1, RRM2) and stromal components (hyaluroninc acid, podoplanin, masson trichrome, picrosirius) were assessed by qRT-PCR and immunohistochemistry in murine LSL-KrasG12D/+;LSL-Trp53R172 H/+; Pdx-1-Cre (KPC), orthotopically transplanted mice (OTM), human primary resected PDAC tissue (hPRT), corresponding patient-derived xenograft (PDX) mice, and KPC-SPARC-/- mice. mRNA expression of GME was analyzed in PDAC cell lines (Panc-1, MIA PaCa, BXPC3 and L3.6) upon incubation on collagen or pancreatic stellate cell (PSC) conditioned media by qRT-PCR.

RESULTS

Endogenous KPC tumors exhibited significantly higher levels of GME compared to OTM. However, GME levels did not differ between hPRT and corresponding PDX mice. Using Kendalls Tau correlation coefficient we did not show a significant correlation of GME and components of the TME except for NT5C1A and hyaluronic acid in PDX mice (p=0.029). GME were not significantly altered upon SPARC depletion in vivo, and upon treatment with PSC-conditioned media or incubation on collagen plated dishes in vitro.

CONCLUSIONS

Our findings suggest that the expression of GME is independent from the deposition of stromal components. KPC mice are most appropriate to study stromal composition whereas PDX mice maintain GME expression of the corresponding hPRT and could be best suited for pharmacokinetic studies.

Prospect of Gold Nanoparticles in Pancreatic Cancer

Pancreatic cancer (PC) is characterized by its notably poor prognosis and high mortality rate, underscoring the critical need for advancements in its diagnosis and therapy. Gold nanoparticles (AuNPs), with their distinctive physicochemical characteristics, demonstrate significant application potential in cancer therapy. For example, upon exposure to lasers of certain wavelengths, they facilitate localized heating, rendering them extremely effective in photothermal therapy. Additionally, their extensive surface area enables the conjugation of therapeutic agents or targeting molecules, increasing the accuracy of drug delivery systems. Moreover, AuNPs can serve as radiosensitizers, enhancing the efficacy of radiotherapy by boosting the radiation absorption in tumor cells. Here, we systematically reviewed the application and future directions of AuNPs in the diagnosis and treatment of PC. Although AuNPs have advantages in improving diagnostic and therapeutic efficacy, as well as minimizing damage to normal tissues, concerns about their potential toxicity and safety need to be comprehensively evaluated.

Cancer-associated fibroblasts in pancreatic ductal adenocarcinoma therapy: Challenges and opportunities

Pancreatic ductal adenocarcinoma (PDAC) is a solid organ malignancy with a high mortality rate. Statistics indicate that its incidence has been increasing as well as the associated deaths. Most patients with PDAC show poor response to therapies making the clinical management of this cancer difficult. Stromal cells in the tumor microenvironment (TME) contribute to the development of resistance to therapy in PDAC cancer cells. Cancer-associated fibroblasts (CAFs), the most prevalent stromal cells in the TME, promote a desmoplastic response, produce extracellular matrix proteins and cytokines, and directly influence the biological behavior of cancer cells. These multifaceted effects make it difficult to eradicate tumor cells from the body. As a result, CAF-targeting synergistic therapeutic strategies have gained increasing attention in recent years. However, due to the substantial heterogeneity in CAF origin, definition, and function, as well as high plasticity, majority of the available CAF-targeting therapeutic approaches are not effective, and in some cases, they exacerbate disease progression. This review primarily elucidates on the effect of CAFs on therapeutic efficiency of various treatment modalities, including chemotherapy, radiotherapy, immunotherapy, and targeted therapy. Strategies for CAF targeting therapies are also discussed.

VISTA antibody-loaded Fe3O4@TiO2 nanoparticles for sonodynamic therapy-synergistic immune checkpoint therapy of pancreatic cancer

Breaking the poor permeability of immune checkpoint inhibitors (ICIs) caused by the stromal barrier and reversing the immunosuppressive microenvironment are significant challenges in pancreatic cancer immunotherapy. In this study, we synthesized core-shell Fe3O4@TiO2 nanoparticles to act as carriers for loading VISTA monoclonal antibodies to form Fe3O4@TiO2@VISTAmAb (FTV). The nanoparticles are designed to target the overexpressed ICIs VISTA in pancreatic cancer, aiming to improve magnetic resonance imaging-guided sonodynamic therapy (SDT)-facilitated immunotherapy. Laser confocal microscopy and flow cytometry results demonstrate that FTV nanoparticles are specifically recognized and phagocytosed by Panc-2 cells. In vivo experiments reveal that ultrasound-triggered TiO2 SDT can induce tumor immunogenic cell death (ICD) and recruit T-cell infiltration within the tumor microenvironment by releasing damage-associated molecular patterns (DAMPs). Furthermore, ultrasound loosens the dense fibrous stroma surrounding the pancreatic tumor and increases vascular density, facilitating immune therapeutic efficiency. In summary, our study demonstrates that FTV nanoparticles hold great promise for synergistic SDT and immunotherapy in pancreatic cancer.

Biodistribution and therapeutic efficacy of a gold nanoparticle-based targeted drug delivery system against pancreatic cancer

Pancreatic cancer is characterized by desmoplasia; crosstalk between pancreatic cancer cells (PCCs) and pancreatic stellate cells (PSCs) leads to the deposition of extracellular matrix proteins in the tumor environment resulting in poor vascularity. Targeting either PCCs or PSCs individually has produced mixed results, and there is currently no effective strategy to target both cell types simultaneously. Previously, we demonstrated, through in vitro cell culture experiments, that a specific gold nanoparticle-based nanoformulation containing the anti-EGFR antibody cetuximab (C225) as a targeting agent and gemcitabine as a chemotherapeutic agent effectively targets both PCCs and PSCs simultaneously. Herein, we extend our studies to test the ability of these in vitro tested nano formulations to inhibit tumor growth in an orthotopic co-implantation model of pancreatic cancer in vivo. Orthotopic tumors were established by co-implantation of equal numbers of PCCs and PSCs in the mouse pancreas. Among the various formulations tested, 5 nm gold nanoparticles coated with gemcitabine, cetuximab and poly-ethylene glycol (PEG) of molecular weight 1000 Da, which we named ACGP441000, demonstrated optimal efficacy in inhibiting tumor growth. The current study reveals an opportunity to target PCCs and PSCs simultaneously, by exploiting their overexpression of EGFR as a target, in order to inhibit pancreatic cancer growth.

The mechanism of USP43 in the development of tumor: a literature review

Ubiquitination of the proteins is crucial for governing protein degradation and regulating fundamental cellular processes. Deubiquitinases (DUBs) have emerged as significant regulators of multiple pathways associated with cancer and other diseases, owing to their capacity to remove ubiquitin from target substrates and modulate signaling. Consequently, they represent potential therapeutic targets for cancer and other life-threatening conditions. USP43 belongs to the DUBs family involved in cancer development and progression. This review aims to provide a comprehensive overview of the existing scientific evidence implicating USP43 in cancer development. Additionally, it will investigate potential small-molecule inhibitors that target DUBs that may have the capability to function as anti-cancer medicines.

Identifying Optimal Candidates for Primary Tumor Resection Among Metastatic Pancreatic Cancer Patients: A Population-Based Predictive Model

BACKGROUND

There is a controversy about whether surgery should proceed among metastatic pancreatic cancer (mPC) patients. A survival benefit was observed in mPC patients who underwent primary tumor resection; however, determining which patients would benefit from surgery is complex. For this purpose, we created a model to identify mPC patients who may benefit from primary tumor excision.

METHODS

Patients with mPC were extracted from the Surveillance, Epidemiology, and End Results database, and separated into surgery and nonsurgery groups based on whether the primary tumor was resected. Propensity score matching (PSM) was applied to balance confounding factors between the two groups. A nomogram was developed using multivariable logistic regression to estimate surgical benefit. Our model is evaluated using multiple methods.

RESULTS

About 662 of 14,183 mPC patients had primary tumor surgery. Kaplan-Meier analyses showed that the surgery group had a better prognosis. After PSM, a survival benefit was still observed in the surgery group. Among the surgery cohort, 202 patients survived longer than 4 months (surgery-beneficial group). The nomogram discriminated better in training and validation sets under the receiver operating characteristic (ROC) curve (AUC), and calibration curves were consistent. Decision curve analysis (DCA) revealed that it was clinically valuable. This model is better at identifying candidates for primary tumor excision.

CONCLUSION

A helpful prediction model was developed and validated to identify ideal candidates who may benefit from primary tumor resection in mPC.

Treatment resistance in pancreatic and biliary tract cancer: molecular and clinical pharmacology perspectives

INTRODUCTION

Treatment resistance poses a significant obstacle in oncology, especially in biliary tract cancer (BTC) and pancreatic cancer (PC). Current therapeutic options include chemotherapy, targeted therapy, and immunotherapy. Resistance to these treatments may arise due to diverse molecular mechanisms, such as genetic and epigenetic modifications, altered drug metabolism and efflux, and changes in the tumor microenvironment. Identifying and overcoming these mechanisms is a major focus of research: strategies being explored include combination therapies, modulation of the tumor microenvironment, and personalized approaches.

AREAS COVERED

We provide a current overview and discussion of the most relevant mechanisms of resistance to chemotherapy, target therapy, and immunotherapy in both BTC and PC. Furthermore, we compare the different strategies that are being implemented to overcome these obstacles.

EXPERT OPINION

So far there is no unified theory on drug resistance and progress is limited. To overcome this issue, individualized patient approaches, possibly through liquid biopsies or single-cell transcriptome studies, are suggested, along with the potential use of artificial intelligence, to guide effective treatment strategies. Furthermore, we provide insights into what we consider the most promising areas of research, and we speculate on the future of managing treatment resistance to improve patient outcomes.

Development of Clinical Radiomics-Based Models to Predict Survival Outcome in Pancreatic Ductal Adenocarcinoma: A Multicenter Retrospective Study

PURPOSE

This multicenter retrospective study aims to identify reliable clinical and radiomic features to build machine learning models that predict progression-free survival (PFS) and overall survival (OS) in pancreatic ductal adenocarcinoma (PDAC) patients.

METHODS

Between 2010 and 2020 pre-treatment contrast-enhanced CT scans of 287 pathology-confirmed PDAC patients from two sites of the Hopital Universitaire de Bruxelles (HUB) and from 47 hospitals within the HUB network were retrospectively analysed. Demographic, clinical, and survival data were also collected. Gross tumour volume (GTV) and non-tumoral pancreas (RPV) were semi-manually segmented and radiomics features were extracted. Patients from two HUB sites comprised the training dataset, while those from the remaining 47 hospitals of the HUB network constituted the testing dataset. A three-step method was used for feature selection. Based on the GradientBoostingSurvivalAnalysis classifier, different machine learning models were trained and tested to predict OS and PFS. Model performances were assessed using the C-index and Kaplan-Meier curves. SHAP analysis was applied to allow for post hoc interpretability.

RESULTS

A total of 107 radiomics features were extracted from each of the GTV and RPV. Fourteen subgroups of features were selected: clinical, GTV, RPV, clinical & GTV, clinical & GTV & RPV, GTV-volume and RPV-volume both for OS and PFS. Subsequently, 14 Gradient Boosting Survival Analysis models were trained and tested. In the testing dataset, the clinical & GTV model demonstrated the highest performance for OS (C-index: 0.72) among all other models, while for PFS, the clinical model exhibited a superior performance (C-index: 0.70).

CONCLUSIONS

An integrated approach, combining clinical and radiomics features, excels in predicting OS, whereas clinical features demonstrate strong performance in PFS prediction.

Viscoelastic stiffening of gelatin hydrogels for dynamic culture of pancreatic cancer spheroids

The tumor microenvironment (TME) in pancreatic adenocarcinoma (PDAC) is a complex milieu of cellular and non-cellular components. Pancreatic cancer cells (PCC) and cancer-associated fibroblasts (CAF) are two major cell types in PDAC TME, whereas the non-cellular components are enriched with extracellular matrices (ECM) that contribute to high stiffness and fast stress-relaxation. Previous studies have suggested that higher matrix rigidity promoted aggressive phenotypes of tumors, including PDAC. However, the effects of dynamic viscoelastic matrix properties on cancer cell fate remain largely unexplored. The focus of this work was to understand the effects of such dynamic matrix properties on PDAC cell behaviors, particularly in the context of PCC/CAF co-culture. To this end, we engineered gelatin-norbornene (GelNB) based hydrogels with a built-in mechanism for simultaneously increasing matrix elastic modulus and viscoelasticity. Two GelNB-based macromers, namely GelNB-hydroxyphenylacetic acid (GelNB-HPA) and GelNB-boronic acid (GelNB-BA), were modularly mixed and crosslinked with 4-arm poly(ethylene glycol)-thiol (PEG4SH) to form elastic hydrogels. Treating the hybrid hydrogels with tyrosinase not only increased the elastic moduli of the gels (due to HPA dimerization) but also concurrently produced 1,2-diols that formed reversible boronic acid-diol bonding with the BA groups on GelNB-BA. We employed patient-derived CAF and a PCC cell line COLO-357 to demonstrate the effect of increasing matrix stiffness and viscoelasticity on CAF and PCC cell fate. Our results indicated that in the stiffened environment, PCC underwent epithelial-mesenchymal transition. In the co-culture PCC and CAF spheroid, CAF enhanced PCC spreading and stimulated collagen 1 production. Through mRNA-sequencing, we further showed that stiffened matrices, regardless of the degree of stress-relaxation, heightened the malignant phenotype of PDAC cells. STATEMENT OF SIGNIFICANCE: The pancreatic cancer microenvironment is a complex milieu composed of various cell types and extracellular matrices. It has been suggested that stiffer matrices could promote aggressive behavior in pancreatic cancer, but the effect of dynamic stiffening and matrix stress-relaxation on cancer cell fate remains largely undefined. This study aimed to explore the impact of dynamic changes in matrix viscoelasticity on pancreatic ductal adenocarcinoma (PDAC) cell behavior by developing a hydrogel system capable of simultaneously increasing stiffness and stress-relaxation on demand. This is achieved by crosslinking two gelatin-based macromers through orthogonal thiol-norbornene photochemistry and post-gelation stiffening with mushroom tyrosinase. The results revealed that higher matrix stiffness, regardless of the degree of stress relaxation, exacerbated the malignant characteristics of PDAC cells.

Single-cell RNA sequencing highlights epithelial and microenvironmental heterogeneity in malignant progression of pancreatic ductal adenocarcinoma

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are bona fide precursor lesions of pancreatic ductal adenocarcinoma (PDAC). Single-cell transcriptomics provides a unique perspective for dissecting the epithelial and microenvironmental heterogeneity that accompanies progression from benign IPMNs to invasive PDAC. Single-cell RNA sequencing was performed through droplet-based sequencing on 35 693 cells from three high-grade IPMNs and two IPMN-derived PDACs (all surgically resected). Analysis of single-cell transcriptomes revealed heterogeneous alterations within the epithelium and the tumor microenvironment during the progression of noninvasive dysplasia to invasive cancer. For epithelial cells, we identified acinar-ductal cells and isthmus-pit cells enriched in IPMN lesions and profiled three types of PDAC-unique ductal cells. Notably, a proinflammatory immune component was distinctly observed in IPMNs, comprising CD4+ T cells, CD8+ T cells, and B cells, whereas M2 macrophages were significantly accumulated in PDAC. Through the analysis of cellular communication, the osteopontin gene (SPP1)-CD44 pathway between macrophages and epithelial cells were particularly strengthened in the PDAC group. Further prognostic analysis revealed that SPP1 is a biomarker of IPMN carcinogenesis for surveillance. This study demonstrates the ability to perform high-resolution profiling of single cellular transcriptomes during the progression of high-grade IPMNs to cancer. Notably, single-cell analysis provides an unparalleled insight into both epithelial and microenvironmental heterogeneity associated with early cancer pathogenesis and provides practical markers for surveillance and targets for cancer interception.

Impact of intratumoral microbiome on tumor immunity and prognosis in human pancreatic ductal adenocarcinoma

BACKGROUND

Recent evidence suggests that the presence of microbiome within human pancreatic ductal adenocarcinoma (PDAC) tissue potentially influences cancer progression and prognosis. However, the significance of tumor-resident microbiome remains unclear. We aimed to elucidate the impact of intratumoral bacteria on the pathophysiology and prognosis of human PDAC.

METHODS

The presence of intratumoral bacteria was assessed in 162 surgically resected PDACs using quantitative polymerase chain reaction (qPCR) and in situ hybridization (ISH) targeting 16S rRNA. The intratumoral microbiome was explored by 16S metagenome sequencing using DNA extracted from formalin-fixed paraffin-embedded tissues. The profile of intratumoral bacteria was compared with clinical information, pathological findings including tumor-infiltrating T cells, tumor-associated macrophage, fibrosis, and alterations in four main driver genes (KRAS, TP53, CDKN2A/p16, SMAD4) in tumor genomes.

RESULTS

The presence of intratumoral bacteria was confirmed in 52 tumors (32%) using both qPCR and ISH. The 16S metagenome sequencing revealed characteristic bacterial profiles within these tumors, including phyla such as Proteobacteria and Firmicutes. Comparison of bacterial profiles between cases with good and poor prognosis revealed a significant positive correlation between a shorter survival time and the presence of anaerobic bacteria such as Bacteroides, Lactobacillus, and Peptoniphilus. The abundance of these bacteria was correlated with a decrease in the number of tumor-infiltrating T cells positive for CD4, CD8, and CD45RO.

CONCLUSIONS

Intratumoral infection of anaerobic bacteria such as Bacteroides, Lactobacillus, and Peptoniphilus is correlated with the suppressed anti-PDAC immunity and poor prognosis.

Successful immunotherapy with PD-1 Iinhibitor for advanced pancreatic cancer: report of two cases and review of literature

Pancreatic cancer is a highly malignant tumor, and most patients are diagnosed at an advanced stage. Unfortunately, due to the immunosuppressive tumor microenvironment of pancreatic cancer, the benefits of immunotherapy for patients with advanced pancreatic cancer are still unclear. Here, we present two cases of advanced pancreatic cancer being controlled by immunotherapy, with pathological diagnoses of ductal adenocarcinoma and acinar cell carcinoma, respectively. Next-generation sequencing (NGS) of both patients is high tumor mutation burden (tumor mutation burden-High) and microsatellite stable. The patient with pancreatic ductal adenocarcinoma was diagnosed as a locally advanced disease (stage III). She received irreversible electroporation, used the programmed death receptor-1 (PD-1) inhibitor (pembrolizumab) combined with chemotherapy (S-1), and then used only the PD-1 inhibitor as a maintenance treatment. As a result, the patient's lesion was significantly reduced, with a partial response time of up to 31 months. The patient with acinar cell carcinoma was diagnosed as a metastatic disease (stage IV), next-generation sequencing revealed mutations in SMAD4 and KMT2D, and two chemotherapy regimens were used unsuccessfully. Then, the combination of chemotherapy with PD-1 (tislelizumab) and vascular endothelial growth factor/vascular endothelial growth factor receptor (anlotinib) inhibitors were used, and the lesions of the patient were significantly reduced, and the progression-free survival after immunotherapy was 19 months. In advanced pancreatic cancer, a prognosis of this magnitude is rare. Our cases reveal the potential of immunotherapy as a cornerstone treatment in the management of advanced pancreatic cancer.

Pancreatic ductal adenocarcinoma chemoresistance: From metabolism reprogramming to novel treatment

ABSTRACT

As pancreatic cancer (PC) is highly malignant, its patients tend to develop metastasis at an early stage and show a poor response to conventional chemotherapies. First-line chemotherapies for PC, according to current guidelines, include fluoropyrimidine- and gemcitabine-based regimens. Accumulating research on drug resistance has shown that biochemical metabolic aberrations in PC, especially those involving glycolysis and glutamine metabolism, are highly associated with chemoresistance. Additionally, lipid metabolism is a major factor in chemoresistance. However, emerging compounds that target these key metabolic pathways have the potential to overcome chemoresistance. This review summarizes how PC develops chemoresistance through aberrations in biochemical metabolism and discusses novel critical targets and pathways within cancer metabolism for new drug research.

Albumin conjugation promotes arsenic trioxide transport through alkaline phosphatase-associated transcytosis in MUC4 wildtype pancreatic cancer cells

Pancreatic cancer (PC) has a poor prognosis due to chemotherapy resistance and unfavorable drug transportation. Albumin conjugates are commonly used as drug carriers to overcome these obstacles. However, membrane-bound glycoprotein mucin 4 (MUC4) has emerged as a promising biomarker among the genetic mutations affecting albumin conjugates therapeutic window. Human serum albumin-conjugated arsenic trioxide (HSA-ATO) has shown potential in treating solid tumors but is limited in PC therapy due to unclear targets and mechanisms. This study investigated the transport mechanisms and therapeutic efficacy of HSA-ATO in PC cells with different MUC4 mutation statuses. Results revealed improved penetration of ATO into PC tumors through conjugated with HSA. However, MUC4 mutation significantly affected treatment sensitivity and HSA-ATO uptake both in vitro and in vivo. Mutant MUC4 cells exhibited over ten times higher IC50 for HSA-ATO and approximately half the uptake compared to wildtype cells. Further research demonstrated that ALPL activation by HSA-ATO enhanced transcytosis in wildtype MUC4 PC cells but not in mutant MUC4 cells, leading to impaired uptake and weaker antitumor effects. Reprogramming the transport process holds potential for enhancing albumin conjugate efficacy in PC patients with different MUC4 mutation statuses, paving the way for stratified treatment using these delivery vehicles.

Glycogen synthase kinase 3β: the nexus of chemoresistance, invasive capacity, and cancer stemness in pancreatic cancer

The treatment of pancreatic cancer remains a significant clinical challenge due to the limited number of patients eligible for curative (R0) surgery, failures in the clinical development of targeted and immune therapies, and the pervasive acquisition of chemotherapeutic resistance. Refractory pancreatic cancer is typified by high invasiveness and resistance to therapy, with both attributes related to tumor cell stemness. These malignant characteristics mutually enhance each other, leading to rapid cancer progression. Over the past two decades, numerous studies have produced evidence of the pivotal role of glycogen synthase kinase (GSK)3β in the progression of over 25 different cancer types, including pancreatic cancer. In this review, we synthesize the current knowledge on the pathological roles of aberrant GSK3β in supporting tumor cell proliferation and invasion, as well as its contribution to gemcitabine resistance in pancreatic cancer. Importantly, we discuss the central role of GSK3β as a molecular hub that mechanistically connects chemoresistance, tumor cell invasion, and stemness in pancreatic cancer. We also discuss the involvement of GSK3β in the formation of desmoplastic tumor stroma and in promoting anti-cancer immune evasion, both of which constitute major obstacles to successful cancer treatment. Overall, GSK3β has characteristics of a promising therapeutic target to overcome chemoresistance in pancreatic cancer.

Epigenetic therapeutic strategies in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal solid malignancies, characterized by its aggressiveness and metastatic potential, with a 5-year survival rate of only 8-11%. Despite significant improvements in PDAC treatment and management, therapeutic alternatives are still limited. One of the main reasons is its high degree of intra- and inter-individual tumor heterogeneity which is established and maintained through a complex network of transcription factors and epigenetic regulators. Epigenetic drugs, have shown promising preclinical results in PDAC and are currently being evaluated in clinical trials both for their ability to sensitize cancer cells to cytotoxic drugs and to counteract the immunosuppressive characteristic of PDAC tumor microenvironment. In this review, we discuss the current status of epigenetic treatment strategies to overcome molecular and cellular PDAC heterogeneity in order to improve response to therapy.

Role of tumor budding and fibrotic cancer stroma in head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is an aggressive cancer with an increased frequency of lymph node metastasis at the time of presentation. Tumour budding, characterised by the presence of a single cell or a small grouping of tumour cells (a cluster containing fewer than five malignant cells) at the invasive front and composition of the fibrotic cancer stroma has been demonstrated to have a growing impact on the behaviour of the solid tumour. However exact role played by them is yet to be defined and a standardized scoring system needs to be incorporated.

MATERIAL AND METHODS

A total of 45 histopathologically confirmed cases of HNSCC were included in the study. Hematoxylin and Eosin staining (H&E staining), and immunohistochemistry for CK and alpha-SMA were applied to study the tumour budding and fibrotic cancer stroma in all HNSCC cases. The tumour budding was graded as, Grade 1: 0-4 tumour buds, Grade 2: 5-9 buds and Grade 3: ≥ 10 buds and the nature of fibrotic cancer stroma was categorized as mature, intermediate or immature.

RESULTS

Among 45 cases analyzed, well differentiated squamous cell carcinoma (WDSCC; Grade 1) accounted for 42.22% (19 cases), whereas moderately differentiated squamous cell carcinoma (MDSCC; Grade 2) and poorly differentiated squamous cell carcinoma (PDSCC; Grade 3) comprised 48.89% (22 cases) and 8.89% (4 cases) respectively. Tumour budding showed instances of 0-4 buds in 33.3% (Grade 1), 5-9 buds in 48.9% (Grade 2), and ≥ 10 buds in 17.8% of cases. Evaluating tumour stroma, Intermediate stroma led at 51.1%, Mature at 37.8%, and 11.1% displayed Immature stroma. Histologically, < 5 buds were seen in 47.4% of Grade 1 cases, while ≥ 10 buds were in 75.0% of Grade 3 cases, proven statistically significant (p = 0.021). However, an association between T&N Stage and tumour budding lacked significance. WDSCC notably had more mature stroma than MDSCC and PDSCC, whereas MDSCC showed higher rates of intermediate and immature stroma (p < 0.001). Comparatively, no significant correlation existed between fibrotic stroma and tumour budding (p = 0.076). Also, fibrotic stroma was compared with tumour budding, however, no significant correlation was found (p = 0.076) CONCLUSION: This study reveals a significant link between tumour budding, cancer stroma, and WHO tumour grade. Thus, evaluating these factors in HNSCC cases can serve as valuable histological prognostic indicators, aiding in treatment planning and prognosis assessment.

CAFs Homologous Biomimetic Liposome Bearing BET Inhibitor and Pirfenidone Synergistically Promoting Antitumor Efficacy in Pancreatic Ductal Adenocarcinoma

BRD4 is a member of the BET protein family involved in chromatin remodeling and transcriptional regulation. Several BET inhibitors (BETi) have entered clinical trials, demonstrating potential in inducing cancer cell apoptosis and tumor regression. However, resistance to BETi is common in solid tumors. In pancreatic cancer, it is found that cancer-associated fibroblasts (CAFs) in the tumor microenvironment reduce the BET inhibitor JQ1 sensitivity by inducing BRD4 expression. Moreover, CAFs play a crucial role in the formation of a dense stromal barrier. Therefore, targeting CAFs in the tumor microenvironment of pancreatic cancer not only enhances cancer cells sensitivity to JQ1 but also increases drug perfusion and improves oxygen supply, thus reducing glycolysis and limiting energy supply. To address this challenge, a homologous targeting mechanism utilizing activated fibroblast membrane-coated liposomes is proposed for specific drug precise target to CAFs-rich pancreatic cancer. Additionally, TAT peptides enable liposomes penetration, delivering PFD for targeted anti-fibrotic therapy, reducing extracellular matrix generation and glycolysis, and enhancing JQ1 delivery and sensitivity. In conclusion, the findings indicate the tremendous potential of this CAFs-targeting liposomal delivery system in pancreatic cancer.

An Update on Gemcitabine-Based Chemosensitization Strategies in Pancreatic Ductal Adenocarcinoma

Pancreatic cancer is the seventh leading cause of cancer-related deaths, and chemotherapy is one of the most important treatments for pancreatic cancer. Unfortunately, pancreatic cancer cells can block chemotherapy drugs from entering the tumor. This is owing to interactions between the tumor's environment and the cancer cells. Here, we review the latest research on the mechanisms by which pancreatic cancer cells block the chemotherapy drug, gemcitabine. The results of our review can help identify potential therapeutic targets for the blocking of gemcitabine by pancreatic cancer cells and may provide new strategies to help chemotherapy drugs penetrate tumors.

Machine learning algorithm integrates bulk and single-cell transcriptome sequencing to reveal immune-related personalized therapy prediction features for pancreatic cancer

Pancreatic cancer (PC) is a digestive malignancy with worse overall survival. Tumor immune environment (TIME) alters the progression and proliferation of various solid tumors. Hence, we aimed to detect the TIME-related classifier to facilitate the personalized treatment of PC. Based on the 1612 immune-related genes (IRGs), we classified patients into Immune_rich and Immune_desert subgroups via consensus clustering. Patients in distinct subtypes exhibited a difference in sensitivity to immune checkpoint blockers (ICB). Next, the immune-related signature (IRS) model was established based on 8 IRGs (SYT12, TNNT1, TRIM46, SMPD3, ANLN, AFF3, CXCL9 and RP1L1) and validated its predictive efficiency in multiple cohorts. RT-qPCR experiments demonstrated the differential expression of 8 IRGs between tumor and normal cell lines. Patients who gained lower IRS score tended to be more sensitive to chemotherapy and immunotherapy, and obtained better overall survival compared to those with higher IRS scores. Moreover, scRNA-seq analysis revealed that fibroblast and ductal cells might affect malignant tumor cells via MIF-(CD74+CD44) and SPP1-CD44 axis. Eventually, we identified eight therapeutic targets and one agent for IRS high patients. Our study screened out the specific regulation pattern of TIME in PC, and shed light on the precise treatment of PC.

The spatiotemporal journey of nanomedicines in solid tumors on their therapeutic efficacy

The rapid development of nanomedicines is revolutionizing the landscape of cancer treatment, while effectively delivering them into solid tumors remains a formidable challenge. Currently, there is a huge disconnect on therapeutic response between regulatory approved nanomedicines and laboratory reported nanoparticles. The discrepancy is mainly resulted from the failure of using the classic overall pharmacokinetics behaviors of nanomedicines in tumors to predict the antitumor efficacy. Increasing evidence has revealed that the therapeutic efficacy predominantly relies on the intratumoral spatiotemporal distribution of nanomedicines. This review focuses on the spatiotemporal distribution of systemically administered chemotherapeutic nanomedicines in solid tumor. Firstly, the intratumoral biological barriers that regulate the spatiotemporal distribution of nanomedicines are described in detail. Next, the influences on antitumor efficacy caused by the spatial distribution and temporal drug release of nanomedicines are emphatically analyzed. Then, current methodologies for evaluating the spatiotemporal distribution of nanomedicines are summarized. Finally, the advanced strategies to positively modulate the spatiotemporal distribution of nanomedicines for an optimal tumor therapy are comprehensively reviewed.

Therapeutic Strategies for Pancreatic-Cancer-Related Type 2 Diabetes Centered around Natural Products

Pancreatic ductal adenocarcinoma (PDAC), a highly malignant neoplasm, is classified as one of the most severe and devastating types of cancer. PDAC is a notable malignancy that exhibits a discouraging prognosis and a rising occurrence. The interplay between diabetes and pancreatic cancer exhibits a reciprocal causation. The identified metabolic disorder has been observed to possess noteworthy consequences on health outcomes, resulting in elevated rates of morbidity. The principal mechanisms involve the suppression of the immune system, the activation of pancreatic stellate cells (PSCs), and the onset of systemic metabolic disease caused by dysfunction of the islets. From this point forward, it is important to recognize that pancreatic-cancer-related diabetes (PCRD) has the ability to increase the likelihood of developing pancreatic cancer. This highlights the complex relationship that exists between these two physiological states. Therefore, we investigated into the complex domain of PSCs, elucidating their intricate signaling pathways and the profound influence of chemokines on their behavior and final outcome. In order to surmount the obstacle of drug resistance and eliminate PDAC, researchers have undertaken extensive efforts to explore and cultivate novel natural compounds of the next generation. Additional investigation is necessary in order to comprehensively comprehend the effect of PCRD-mediated apoptosis on the progression and onset of PDAC through the utilization of natural compounds. This study aims to examine the potential anticancer properties of natural compounds in individuals with diabetes who are undergoing chemotherapy, targeted therapy, or immunotherapy. It is anticipated that these compounds will exhibit increased potency and possess enhanced pharmacological benefits. According to our research findings, it is indicated that naturally derived chemical compounds hold potential in the development of PDAC therapies that are both safe and efficacious.

Desmoplasia in cervical cancer is associated with a more aggressive tumor phenotype

In cancer of the uterine cervix, the role of desmoplasia, i.e., peritumoral stromal remodeling characterized by fibroblast activation and increased extracellular matrix deposition, is not established. We conducted a retrospective cohort study based on data from 438 patients who had undergone surgical treatment for cervical cancer as part of the prospective Leipzig Mesometrial Resection study between 1999 and 2021. Using non-parametric tests, Kaplan-Meier plotting, and Cox regression modeling, we calculated the prognostic impact of desmoplasia and its association with other risk factors. Desmoplasia was present in 80.6% of cases and was associated with a higher frequency of lymphovascular space involvement (76.5 vs. 56.5%, p < 0.001) and venous infiltration (14.4 vs. 2.4%, p < 0.001). Lymph node metastasis (23.0 vs. 11.8%, p < 0.05) and parametrial involvement (47.3 vs. 17.6%, p < 0.0001) were also more common in patients with desmoplasia. The presence of desmoplasia was associated with inferior overall (80.2% vs. 94.5% hazard ratio [HR] 3.8 [95% CI 1.4-10.4], p = 0.002) and recurrence-free survival (75.3% vs. 87.3%, HR 2.3 [95% CI 1.2-4.6], p = 0.008). In addition, desmoplasia was associated with significantly less peritumoral inflammation (rho - 0.43, p < 0.0001). In summary, we link desmoplasia to a more aggressive phenotype of cervical cancer, reduced peritumoral inflammation, and inferior survival.

High expression ITGA2 affects the expression of MET, PD-L1, CD4 and CD8 with the immune microenvironment in pancreatic cancer patients

Purpose

Pancreatic cancer is characterized by a grim prognosis and is regarded as one of the most formidable malignancies. Among the genes exhibiting high expression in different tumor tissues, ITGA2 stands out as a promising candidate for cancer therapy. The promotion of cancer in pancreatic cancer is not effective. The objective of this study is to assess the presence of ITGA2, EMT and PD-L1 in pancreatic cancer.

Experimental design

We examined the expression of ITGA2, MET, E-cadherin, PD-L1, CD4, and CD8 proteins in 62 pancreatic cancer tissue samples using multi-tissue immunofluorescence and immunohistochemistry techniques. Functional assays, such as the cell migration assay and transwell assay, were used to determine the biological role of ITGA2 in pancreatic cancer. The relationship of ITGA2,EMT and PD-L1 were examined using Western blot analysis and RT-qPCR assay.

Results

In our study, we observed the expression of ITGA2, E-cadherin, and PD-L1 in both tumor and stroma tissues of pancreatic cancer. Additionally, a positive correlation between ITGA2, E-cadherin, and PD-L1 in the tumor region (r=0.559, P<0.001 and r=0.511, P<0.001), and PD-L1 in the stroma region (r=0.512, P<0.001).The expression levels of ITGA2, CD4, and CD8 were found to be higher in pancreatic cancer tissues compared to adjacent tissues (P < 0.05). Additionally, ITGA2 was negatively correlated with CD4 and CD8 (r = -0.344, P < 0.005 and r = -0.398, P < 0.005).Furthermore, ITGA2, CD4, and CD8 were found to be correlated with the survival time of patients (P < 0.05). Blocking ITGA2 inhibited the proliferation and invasion ability of pancreatic cancer cells significantly, Additionally, sh-ITGA2 can down-regulate the expression of EMT and PD-L1.

Conclusions

We identified a novel mechanism in which ITGA2 plays a crucial role in the regulation of pancreatic cancer growth and invasion. This mechanism involves the upregulation of MET and PD-L1 expression in pancreatic cancer cells. Additionally, we found that increased expression of ITGA2 is associated with a poor prognosis in pancreatic cancer patients. Furthermore, ITGA2 also affects immune regulation in these patients. Therefore, targeting ITGA2 is an effective method to enhance the efficacy of checkpoint immunotherapy and prohibiting tumor growth against pancreatic cancer.

Progressing nanotechnology to improve targeted cancer treatment: overcoming hurdles in its clinical implementation

The use of nanotechnology has the potential to revolutionize the detection and treatment of cancer. Developments in protein engineering and materials science have led to the emergence of new nanoscale targeting techniques, which offer renewed hope for cancer patients. While several nanocarriers for medicinal purposes have been approved for human trials, only a few have been authorized for clinical use in targeting cancer cells. In this review, we analyze some of the authorized formulations and discuss the challenges of translating findings from the lab to the clinic. This study highlights the various nanocarriers and compounds that can be used for selective tumor targeting and the inherent difficulties in cancer therapy. Nanotechnology provides a promising platform for improving cancer detection and treatment in the future, but further research is needed to overcome the current limitations in clinical translation.

A comprehensive analysis of tumor-stromal collagen in relation to pathological, molecular, and immune characteristics and patient survival in pancreatic ductal adenocarcinoma

BACKGROUND

Abundant collagen deposition is a hallmark of pancreatic ductal adenocarcinomas (PDACs). This study clarified the interactive relationship between tumor-stromal collagen, molecular and immune characteristics, and tumor pr ogression in human PDAC.

METHODS

We performed a comprehensive examination using an integrative molecular pathological epidemiology database on 169 cases with resected PDAC . The amount of tumor-stromal collagen was quantified through digital imaging analysis for Elastica van Gieson-stained whole-section tumor slides. We analyzed the association of tumor-stromal collagen with gene alterations (KRAS, TP53, CDKN2A/p16, and SMAD4), immune parameters (CD4+ tumor-infiltrating lymphocytes [TILs], CD8+ TILs, FOXP3+ TILs, and tertiary lymphoid structures), and patient prognosis.

RESULTS

Low amounts of tumor-stromal collagen were associated with poor differentiation (multivariable OR = 3.82, 95%CI = 1.41-12.2, P = 0.008) and CDKN2A/p16 alteration (OR [95%CI] = 2.06 [1.08-4.02], P = 0.03). Tumors with low collagen levels had shorter overall survival (HR [95%CI] = 2.38 [1.59-3.56], P < 0.0001). In the S-1 and gemcitabine (GEM) treatment groups, low tumor-stromal collagen was linked to poor prognosis of patients with PDAC (S-1 group: multivariable HR [95%CI] = 2.76 [1.36-5.79], P = 0.005; GEM group: multivariate HR [95%CI] = 2.91 [1.34-6.71], P = 0.007). Additionally, low amounts of tumor-stromal collagen were also linked to low levels of CD4+ TILs (P = 0.046), CD8+ TILs (P = 0.09), and tertiary lymphoid structures (P = 0.001).

CONCLUSIONS

Tumor-stromal collagen deposition may play a crucial role in modulating tumor-immune microenvironment and determining response to adjuvant chemotherapy and patient survival outcomes.

Theranostics in targeting fibroblast activation protein bearing cells: Progress and challenges

Cancer cells are surrounded by a complex and highly dynamic tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs), a critical component of TME, contribute to cancer cell proliferation as well as metastatic spread. CAFs express a variety of biomarkers, which can be targeted for detection and therapy. Most importantly, CAFs express high levels of fibroblast activation protein (FAP) which contributes to progression of cancer, invasion, metastasis, migration, immunosuppression, and drug resistance. As a consequence, FAP is an attractive theranostic target. In this review, we discuss the latest advancement in targeting FAP in oncology using theranostic biomarkers and imaging modalities such as single-photon emission computed tomography (SPECT), positron emission tomography (PET), computed tomography (CT), fluorescence imaging, and magnetic resonance imaging (MRI).

The importance of CXCR4 expression in tumor stroma as a potential biomarker in pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the main causes of cancer mortality in the world. A characteristic feature of this cancer is that a large part of the tumor volume is composed of a stroma with different cells and factors. Among these, we can highlight the cytokines, which perform their function through binding to their receptors. Given the impact of the CXCR4 receptor in the interactions between tumor cells and their microenvironment and its involvement in important signaling pathways in cancer, it is proposed as a very promising prognostic biomarker and as a goal for new targeted therapies. Numerous studies analyze the expression of CXCR4 but we suggest focusing on the expression of CXCR4 in the stroma.

METHODS

Expression of CXCR4 in specimens from 33 patients with PDAC was evaluated by immunohistochemistry techniques and matched with clinicopathological parameters, overall and disease-free survival rates.

RESULTS

The percentage of stroma was lower in non-tumor tissue (32.4 ± 5.2) than in tumor pancreatic tissue (67.4 ± 4.8), P-value = 0.001. The level of CXCR4 expression in stromal cells was diminished in non-tumor tissue (8.7 ± 4.6) and higher in tumor pancreatic tissue (23.5 ± 6.1), P-value = 0.022. No significant differences were identified in total cell count and inflammatory cells between non-tumor tissue and pancreatic tumor tissue. No association was observed between CXCR4 expression and any of the clinical or pathological data, overall and disease-free survival rates. Analyzing exclusively the stroma of tumor samples, the CXCR4 expression was associated with tumor differentiation, P-value = 0.05.

CONCLUSIONS

In this study, we reflect the importance of CXCR4 expression in the stroma of patients diagnosed with PDAC. Our results revealed a high CXCR4 expression in the tumor stroma, which is related to a poor tumor differentiation. On the contrary, we could not find an association between CXCR4 expression and survival and the rest of the clinicopathological variables. Focusing the study on the CXCR4 expression in the tumor stroma could generate more robust results. Therefore, we consider it key to develop more studies to enlighten the role of this receptor in PDAC and its implication as a possible biomarker.

A first-in-class pan-lysyl oxidase inhibitor impairs stromal remodeling and enhances gemcitabine response and survival in pancreatic cancer

The lysyl oxidase family represents a promising target in stromal targeting of solid tumors due to the importance of this family in crosslinking and stabilizing fibrillar collagens and its known role in tumor desmoplasia. Using small-molecule drug-design approaches, we generated and validated PXS-5505, a first-in-class highly selective and potent pan-lysyl oxidase inhibitor. We demonstrate in vitro and in vivo that pan-lysyl oxidase inhibition decreases chemotherapy-induced pancreatic tumor desmoplasia and stiffness, reduces cancer cell invasion and metastasis, improves tumor perfusion and enhances the efficacy of chemotherapy in the autochthonous genetically engineered KPC model, while also demonstrating antifibrotic effects in human patient-derived xenograft models of pancreatic cancer. PXS-5505 is orally bioavailable, safe and effective at inhibiting lysyl oxidase activity in tissues. Our findings present the rationale for progression of a pan-lysyl oxidase inhibitor aimed at eliciting a reduction in stromal matrix to potentiate chemotherapy in pancreatic ductal adenocarcinoma.

Nanomedicine and epigenetics: New alliances to increase the odds in pancreatic cancer survival

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers worldwide, primarily due to its robust desmoplastic stroma and immunosuppressive tumor microenvironment (TME), which facilitate tumor progression and metastasis. In addition, fibrous tissue leads to sparse vasculature, high interstitial fluid pressure, and hypoxia, thereby hindering effective systemic drug delivery and immune cell infiltration. Thus, remodeling the TME to enhance tumor perfusion, increase drug retention, and reverse immunosuppression has become a key therapeutic strategy. In recent years, targeting epigenetic pathways has emerged as a promising approach to overcome tumor immunosuppression and cancer progression. Moreover, the progress in nanotechnology has provided new opportunities for enhancing the efficacy of conventional and epigenetic drugs. Nano-based drug delivery systems (NDDSs) offer several advantages, including improved drug pharmacokinetics, enhanced tumor penetration, and reduced systemic toxicity. Smart NDDSs enable precise targeting of stromal components and augment the effectiveness of immunotherapy through multiple drug delivery options. This review offers an overview of the latest nano-based approaches developed to achieve superior therapeutic efficacy and overcome drug resistance. We specifically focus on the TME and epigenetic-targeted therapies in the context of PDAC, discussing the advantages and limitations of current strategies while highlighting promising new developments. By emphasizing the immense potential of NDDSs in improving therapeutic outcomes in PDAC, our review paves the way for future research in this rapidly evolving field.