Angiogenesis in Pancreatic Cancer: Pre-Clinical and Clinical Studies

Advances in tumor vascular growth inhibition

Tumor growth and metastasis require neovascularization, which is dependent on a complex array of factors, such as the production of various pro-angiogenic factors by tumor cells, intercellular signaling, and stromal remodeling. The hypoxic, acidic tumor microenvironment is not only conducive to tumor cell proliferation, but also disrupts the equilibrium of angiogenic factors, leading to vascular heterogeneity, which further promotes tumor development and metastasis. Anti-angiogenic strategies to inhibit tumor angiogenesis has, therefore, become an important focus for anti-tumor therapy. The traditional approach involves the use of anti-angiogenic drugs to inhibit tumor neovascularization by targeting upstream and downstream angiogenesis-related pathways or pro-angiogenic factors, thereby inhibiting tumor growth and metastasis. This review explores the mechanisms involved in tumor angiogenesis and summarizes currently used anti-angiogenic drugs, including monoclonal antibody, and small-molecule inhibitors, as well as the progress and challenges associated with their use in anti-tumor therapy. It also outlines the opportunities and challenges of treating tumors using more advanced anti-angiogenic strategies, such as immunotherapy and nanomaterials.

Investigating underlying molecular mechanisms, signaling pathways, emerging therapeutic approaches in pancreatic cancer

Pancreatic adenocarcinoma, a clinically challenging malignancy constitutes a significant contributor to cancer-related mortality, characterized by an inherently poor prognosis. This review aims to provide a comprehensive understanding of pancreatic adenocarcinoma by examining its multifaceted etiologies, including genetic mutations and environmental factors. The review explains the complex molecular mechanisms underlying its pathogenesis and summarizes current therapeutic strategies, including surgery, chemotherapy, and emerging modalities such as immunotherapy. Critical molecular pathways driving pancreatic cancer development, including KRAS, Notch, and Hedgehog, are discussed. Current therapeutic strategies, including surgery, chemotherapy, and radiation, are discussed, with an emphasis on their limitations, particularly in terms of postoperative relapse. Promising research areas, including liquid biopsies, personalized medicine, and gene editing, are explored, demonstrating the significant potential for enhancing diagnosis and treatment. While immunotherapy presents promising prospects, it faces challenges related to immune evasion mechanisms. Emerging research directions, encompassing liquid biopsies, personalized medicine, CRISPR/Cas9 genome editing, and computational intelligence applications, hold promise for refining diagnostic approaches and therapeutic interventions. By integrating insights from genetic, molecular, and clinical research, innovative strategies that improve patient outcomes can be developed. Ongoing research in these emerging fields holds significant promise for advancing the diagnosis and treatment of this formidable malignancy.

Multiplexed Imaging Mass Cytometry Analysis Characterizes the Vascular Niche in Pancreatic Cancer

Oncogenesis and progression of pancreatic ductal adenocarcinoma (PDAC) are driven by complex interactions between the neoplastic component and the tumor microenvironment, which includes immune, stromal, and parenchymal cells. In particular, most PDACs are characterized by a hypovascular and hypoxic environment that alters tumor cell behavior and limits the efficacy of chemotherapy and immunotherapy. Characterization of the spatial features of the vascular niche could advance our understanding of inter- and intratumoral heterogeneity in PDAC. In this study, we investigated the vascular microenvironment of PDAC by applying imaging mass cytometry using a 26-antibody panel on 35 regions of interest across 9 patients, capturing more than 140,000 single cells. The approach distinguished major cell types, including multiple populations of lymphoid and myeloid cells, endocrine cells, ductal cells, stromal cells, and endothelial cells. Evaluation of cellular neighborhoods identified 10 distinct spatial domains, including multiple immune and tumor-enriched environments as well as the vascular niche. Focused analysis revealed differential interactions between immune populations and the vasculature and identified distinct spatial domains wherein tumor cell proliferation occurs. Importantly, the vascular niche was closely associated with a population of CD44-expressing macrophages enriched for a proangiogenic gene signature. Taken together, this study provides insights into the spatial heterogeneity of PDAC and suggests a role for CD44-expressing macrophages in shaping the vascular niche. Significance: Imaging mass cytometry revealed that pancreatic ductal cancers are composed of 10 distinct cellular neighborhoods, including a vascular niche enriched for macrophages expressing high levels of CD44 and a proangiogenic gene signature.

Growth Hormone Receptor Antagonist Markedly Improves Gemcitabine Response in a Mouse Xenograft Model of Human Pancreatic Cancer

Chemotherapy treatment against pancreatic ductal adenocarcinoma (PDAC) is thwarted by tumoral activation of multiple therapy resistance pathways. The growth hormone (GH)-GH receptor (GHR) pair is a covert driver of multimodal therapy resistance in cancer and is overexpressed in PDAC tumors, yet the therapeutic potential of targeting the same has not been explored. Here, we report that GHR expression is a negative prognostic factor in patients with PDAC. Combinations of gemcitabine with different GHR antagonists (GHRAs) markedly improve therapeutic outcomes in nude mice xenografts. Employing cultured cells, mouse xenografts, and analyses of the human PDAC transcriptome, we identified that attenuation of the multidrug transporter and epithelial-to-mesenchymal transition programs in the tumors underlie the observed augmentation of chemotherapy efficacy by GHRAs. Moreover, in human PDAC patients, GHR expression strongly correlates with a gene signature of tumor promotion and immune evasion, which corroborate with that in syngeneic tumors in wild-type vs. GH transgenic mice. Overall, we found that GH action in PDAC promoted a therapy-refractory gene signature in vivo, which can be effectively attenuated by GHR antagonism. Our results collectively present a proof of concept toward considering GHR antagonists to improve chemotherapeutic outcomes in the highly chemoresistant PDAC.

The trend toward more target therapy in pancreatic ductal adenocarcinoma

INTRODUCTION

Despite the considerable progress made in cancer treatment through the development of target therapies, pancreatic ductal adenocarcinoma (PDAC) continues to exhibit resistance to this category of drugs. As a result, chemotherapy combination regimens remain the primary treatment approach for this aggressive cancer.

AREAS COVERED

In this review, we provide an in-depth analysis of past and ongoing trials on both well-known and novel targets that are being explored in PDAC, including PARP, EGFR, HER2, KRAS, and its downstream and upstream pathways (such as RAF/MEK/ERK and PI3K/AKT/mTOR), JAK/STAT pathway, angiogenesis, metabolisms, epigenetic targets, claudin, and novel targets (such as P53 and plectin). We also provide a comprehensive overview of the significant trials for each target, allowing a thorough glimpse into the past and future of target therapy.

EXPERT OPINION

The path toward implementing a target therapy capable of improving the overall survival of PDAC is still long, and it is unlikely that a monotherapy target drug will fulfill a meaningful role in addressing the complexity of this cancer. Thus, we discuss the future direction of target therapies in PDAC, trying to identify the more promising target and combination treatments, with a special focus on the more eagerly awaited ongoing trials.

Fibroblasts in the Aged Pancreas Drive Pancreatic Cancer Progression

Pancreatic cancer is more prevalent in older individuals and often carries a poorer prognosis for them. The relationship between the microenvironment and pancreatic cancer is multifactorial, and age-related changes in nonmalignant cells in the tumor microenvironment may play a key role in promoting cancer aggressiveness. Because fibroblasts have profound impacts on pancreatic cancer progression, we investigated whether age-related changes in pancreatic fibroblasts influence cancer growth and metastasis. Proteomics analysis revealed that aged fibroblasts secrete different factors than young fibroblasts, including increased growth/differentiation factor 15 (GDF-15). Treating young mice with GDF-15 enhanced tumor growth, whereas aged GDF-15 knockout mice showed reduced tumor growth. GDF-15 activated AKT, rendering tumors sensitive to AKT inhibition in an aged but not young microenvironment. These data provide evidence for how aging alters pancreatic fibroblasts and promotes tumor progression, providing potential therapeutic targets and avenues for studying pancreatic cancer while accounting for the effects of aging.

SIGNIFICANCE

Aged pancreatic fibroblasts secrete GDF-15 and activate AKT signaling to promote pancreatic cancer growth, highlighting the critical role of aging-mediated changes in the pancreatic cancer microenvironment in driving tumor progression. See related commentary by Isaacson et al., p. 1185.

Clinical and Preclinical Targeting of Oncogenic Pathways in PDAC: Targeted Therapeutic Approaches for the Deadliest Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer-related death worldwide. It is commonly diagnosed in advanced stages and therapeutic interventions are typically constrained to systemic chemotherapy, which yields only modest clinical outcomes. In this review, we examine recent developments in targeted therapy tailored to address distinct molecular pathway alteration required for PDAC. Our review delineates the principal signaling pathways and molecular mechanisms implicated in the initiation and progression of PDAC. Subsequently, we provide an overview of prevailing guidelines, ongoing investigations, and prospective research trajectories related to targeted therapeutic interventions, drawing insights from randomized clinical trials and other pertinent studies. This review focus on a comprehensive examination of preclinical and clinical data substantiating the efficacy of these therapeutic modalities, emphasizing the potential of combinatorial regimens and novel therapies to enhance the quality of life for individuals afflicted with PDAC. Lastly, the review delves into the contemporary application and ongoing research endeavors concerning targeted therapy for PDAC. This synthesis serves to bridge the molecular elucidation of PDAC with its clinical implications, the evolution of innovative therapeutic strategies, and the changing landscape of treatment approaches.

The Natural Product Parthenolide Inhibits Both Angiogenesis and Invasiveness and Improves Gemcitabine Resistance by Suppressing Nuclear Factor κB Activation in Pancreatic Cancer Cell Lines

We previously established pancreatic cancer (PaCa) cell lines resistant to gemcitabine and found that the activity of nuclear factor κB (NF-κB) was enhanced upon the acquisition of gemcitabine resistance. Parthenolide, the main active ingredient in feverfew, has been reported to exhibit antitumor activity by suppressing the NF-κB signaling pathway in several types of cancers. However, the antitumor effect of parthenolide on gemcitabine-resistant PaCa has not been elucidated. Here, we confirmed that parthenolide significantly inhibits the proliferation of both gemcitabine-resistant and normal PaCa cells at concentrations of 10 µM and higher, and that the NF-κB activity is significantly inhibited, even by 1 µM parthenolide. In Matrigel invasion assays and angiogenesis assays, the invasive and angiogenic potentials were higher in gemcitabine-resistant than normal PaCa cells and were inhibited by a low concentration of parthenolide. Furthermore, Western blotting showed suppressed MRP1 expression in gemcitabine-resistant PaCa treated with a low parthenolide concentration. In a colony formation assay, the addition of 1 µM parthenolide improved the sensitivity of gemcitabine-resistant PaCa cell lines to gemcitabine. These results suggest that parthenolide may be used as a novel therapeutic agent for the treatment of gemcitabine-resistant PaCa.

Research progress of exosomes in the angiogenesis of digestive system tumour

Malignant tumours of the digestive system cover a wide range of diseases that affect the health of people to a large extent. Angiogenesis is indispensable in the development, and metastasis of tumours, mainly in two ways: occupation or formation. Vessels can provide nutrients, oxygen, and growth factors for tumours to encourage growth and metastasis, so cancer progression depends on simultaneous angiogenesis. Recently, exosomes have been proven to participate in the angiogenesis of tumours. They influence angiogenesis by binding to tyrosine kinase receptors (VEGFR)-1, VEGFR-2, and VEGFR-3 with different affinities, regulating Yap-VEGF pathway, Akt pathway or other signaling pathway. Additionally, exosomes are potential therapeutic vectors that can deliver many types of cargoes to different cells. In this review, we summarize the roles of exosomes in the angiogenesis of digestive system tumours and highlight the clinical application prospects, directly used as targers or delivery vehicles, in antiangiogenic therapy.

Angiogenesis and Pancreatic Cancer: Novel Approaches to Overcome Treatment Resistance

Pancreatic cancer (PCa) is acknowledged as a significant contributor to global cancer- related mortality and is widely recognized as one of the most challenging malignant diseases to treat. Pancreatic ductal adenocarcinoma (PDAC), which is the most common type of PCa, is highly aggressive and is mostly incurable. The poor prognosis of this neoplasm is exacerbated by the prevalence of angiogenic molecules, which contribute to stromal stiffness and immune escape. PDAC overexpresses various proangiogenic proteins, including vascular endothelial growth factor (VEGF)-A, and the levels of these molecules correlate with poor prognosis and treatment resistance. Moreover, VEGF-targeting anti-angiogenesis treatments are associated with the onset of resistance due to the development of hypoxia, which in turn induces the production of angiogenic molecules. Furthermore, excessive angiogenesis is one of the hallmarks of the second most common form of PCa, namely, pancreatic neuroendocrine tumor (PNET). In this review, the role of angiogenesis regulators in promoting disease progression in PCa, and the impact of these molecules on resistance to gemcitabine and various therapies against PCa are discussed. Finally, the use of anti-angiogenic agents in combination with chemotherapy and other targeted therapeutic molecules is discussed as a novel solution to overcome current treatment limitations in PCa.

The ethyl acetate extract of Vernonia amygdalina leaf ameliorates gemcitabine effect against migration and invasion of PANC-1 cells via down-regulation the VEGF, COX2, and RAS/MEK pathways

Individuals diagnosed with cancer often turn to the use of herbal remedies with the intention of treating and ameliorating the condition, impeding the progression of metastasis, enhancing immune function, mitigating stress, and inducing relaxation. Recently, medicinal plants were combined with conventional chemotherapy to decrease the side effects and increase the effectiveness of chemotherapy. This study showed the effectiveness of gemcitabine (Gem) was significantly increased after being used together with ethyl acetate extract obtained from Vernonia amygdalina (Eav) leaves. The combination doses of Eav and Gem were determined based on cytotoxic activity using the MTT assay method. The anticancer effect of this combination was identified by several parameters including the apoptosis effect, anti-migration, and anti-invasion activities of PANC-1 cells. Furthermore, this effect was explained via protein expression evaluation using immunohistochemical and flow cytometry. The Eav has a better Inhibitory Concentration 50 (IC50) than Gem of 21.19 ± 0.64 µg/mL and 164.78 ± 1.40 µg/mL. The combination of Eav and Gem at IC50 (1:1) has the strongest activity than Eav and Gem alone at 500.00 µg/mL. The anti-cancer effect of this combination showed significantly increased levels of apoptosis, particularly in the early phase of 17.46 ± 0.35 % (p < 0.0001) than Eav and Gem alone of 7.76 ± 0.25 % and 7.06 ± 0.20 %. A similar impact was evaluated in the migration and invasion of PANC-1 cells after the combination treatment. The % relative migration and cell invasion were significantly decreased compared to the control group and Eav or Gem alone by 21.49 ± 0.96 % and 125.25 ± 5.25 cells, respectively (p < 0.0001). This study found that signature molecules of VEGF, COX2, RAS, and MEK were down-regulated after treatment. Our study suggested that the Eav ameliorates the Gem effect against PANC-1 cells through apoptosis, migration, and invasion influence via RAS/MEK pathways.

A Pilot Study of Paricalcitol plus Nanoliposomal Irinotecan and 5-FU/LV in Advanced Pancreatic Cancer Patients after Progression on Gemcitabine-Based Therapy

PURPOSE

Vitamin D analogues remodel the desmoplastic stroma, and improve vascularity and efficacy of chemotherapy in preclinical pancreas cancer models.

PATIENTS AND METHODS

We conducted a pilot study to evaluate the safety and preliminary efficacy of the vitamin D analogue paricalcitol in combination with nanoliposomal irinotecan (Nal-iri) plus 5-fluorouracil/leucovorin (5-FU/LV) in patients with advanced pancreatic cancer who had progressed on gemcitabine-based therapy. Two dose levels (DL) of paricalcitol were tested: fixed dose weekly (75 mcg, DL1) and weight-based weekly (7 mcg/kg, /DL2). The primary endpoint was safety, and secondary endpoints included overall response rate, progression-free survival (PFS), and overall survival (OS). Correlative objectives aimed to identify molecular predictors of response and alterations in the tumor stroma.

RESULTS

Twenty patients (10 each in DL1 and DL2) enrolled between March 2019 and May 2021. No grade 3/4 adverse events related to paricalcitol were observed. The most common toxicities were nausea, diarrhea and fatigue, which were similar in both cohorts. Three patients discontinued study after one cycle and were not radiographically evaluable. Of the remaining 17 evaluable patients, 2 had partial response and 12 had stable disease. The median PFS for response-evaluable patients in DL1 was 4.14 months, for DL2 was 4.83 months. Intent-to-treat median OS was 6.15 and 6.66 months for DL1 and DL2, respectively. Correlative studies showed increased tumor vascularity in posttreatment samples in patients receiving the higher dose of paricalcitol (DL2).

CONCLUSIONS

Paricalcitol at 7 mcg/kg/week in combination with Nal-iri/ 5-FU/LV is safely tolerated, may increase tumor vascularity and warrants further investigation.

Lysine-372-dependent SUMOylation inhibits the enzymatic activity of glutamine synthases

Glutamine synthetase (GS) is a crucial enzyme involved in de novo synthesis of glutamine and participates in several biological processes, including nitrogen metabolism, nucleotide synthesis, and amino acid synthesis. Post-translational modification makes GS more adaptable to the needs of cells, and acetylation modification of GS at double sites has attracted considerable attention. Despite very intensive research, how SUMOylation affects GS activity at a molecular level remains unclear. Here, we report that previously undiscovered GS SUMOylation which is deficient mutant K372R of GS exhibits more bluntness under glutamine starvation. Mechanistically, glutamine deprivation triggers the GS SUMOylation, and this SUMOylation impaired the protein stability of GS, within a concomitant decrease in enzymatic activity. In addition, we identified SAE1, Ubc9, and PIAS1 as the assembly enzymes of GS SUMOylation respectively. Furthermore, Senp1/2 functions as a SUMO-specific protease to reverse the SUMOylation of GS. This study provides the first evidence that SUMOylation serves as a regulatory mechanism for determining the GS enzymatic activity, contributing to understanding the GS regulation roles in various cellular and pathophysiological processes.

Lycorine inhibits pancreatic cancer cell growth and neovascularization by inducing Notch1 degradation and downregulating key vasculogenic genes

Pancreatic cancer is highly metastatic and lethal with an increasing incidence globally and a 5-year survival rate of only 8%. One of the factors contributing to the high mortality is the lack of effective drugs in the clinical setting. We speculated that effective compounds against pancreatic cancer exist in natural herbs and explored active small molecules among traditional Chinese medicinal herbs. The small molecule lycorine (MW: 323.77) derived from the herb Lycoris radiata inhibited pancreatic cancer cell growth with an IC50 value of 1 μM in a concentration-dependent manner. Lycorine markedly reduced pancreatic cancer cell viability, migration, invasion, neovascularization, and gemcitabine resistance. Additionally, lycorine effectively suppressed tumor growth in mouse xenograft models without obvious toxicity. Pharmacological studies revealed that the levels and half-life of Notch1 oncoprotein in the pancreatic cancer cells Panc-1 and Patu8988 were notably reduced. Moreover, the expression of the key vasculogenic genes Semaphorin 4D (Sema4D) and angiopoietin-2 (Ang-2) were also significantly inhibited by lycorine. Mechanistically, lycorine strongly triggered the degradation of Notch1 oncoprotein through the ubiquitin-proteasome system. In conclusion, lycorine effectively inhibits pancreatic cancer cell growth, migration, invasion, neovascularization, and gemcitabine resistance by inducing degradation of Notch1 oncoprotein and downregulating the key vasculogenic genes Sema4D and Ang-2. Our findings provide a new therapeutic candidate and treatment strategy against pancreatic cancer.

Galectin-1 in Pancreatic Ductal Adenocarcinoma: Bridging Tumor Biology, Immune Evasion, and Therapeutic Opportunities

Pancreatic Ductal Adenocarcinoma (PDAC) remains one of the most challenging malignancies to treat, with a complex interplay of molecular pathways contributing to its aggressive nature. Galectin-1 (Gal-1), a member of the galectin family, has emerged as a pivotal player in the PDAC microenvironment, influencing various aspects from tumor growth and angiogenesis to immune modulation. This review provides a comprehensive overview of the multifaceted role of Galectin-1 in PDAC. We delve into its contributions to tumor stroma remodeling, angiogenesis, metabolic reprogramming, and potential implications for therapeutic interventions. The challenges associated with targeting Gal-1 are discussed, given its pleiotropic functions and complexities in different cellular conditions. Additionally, the promising prospects of Gal-1 inhibition, including the utilization of nanotechnology and theranostics, are highlighted. By integrating recent findings and shedding light on the intricacies of Gal-1's involvement in PDAC, this review aims to provide insights that could guide future research and therapeutic strategies.

Saikosaponin d modulates the polarization of tumor-associated macrophages by deactivating the PI3K/AKT/mTOR pathway in murine models of pancreatic cancer

The tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) poses a major obstacle to traditional and immunomodulatory cancer therapies and is closely associated with macrophage polarization. Saikosaponin d (SSd), a major active component of triterpene saponins derived from Bupleurum falcatum, has anti-inflammatory and antitumor activities. However, whether SSd can regulate immune cells during the development of the TME in PDAC remains unknown. In the present study, we aimed to analyze the role of SSd in regulating immune cells in the PDAC TME, especially the polarization of macrophages, and examine the related mechanisms. An orthotopic PDAC cancer model was used to investigate the antitumor activities and the regulation of immune cells in vivo. In vitro, bone marrow mononuclear (BM-MNC) cells and RAW 264.7 cells were used to induce the M2 macrophage phenotype and examine the effects and molecular mechanism of SSd on M2 macrophage polarization. The results revealed that SSd could directly inhibit the apoptosis and invasion of pancreatic cancer cells, modulate the immunosuppressive microenvironment and reactivate the local immune response, especially by decreasing the shift toward M2 macrophage polarization by downregulating phosphorylated STAT6 levels and the PI3K/AKT/mTOR signaling pathway. Furthermore, 740-Y-P (PI3K activator) was used to verify that SSd inhibited M2 polarization in RAW264.7 cells via the PI3K/AKT/mTOR signaling pathway. In conclusion, this study provided experimental evidence of the antitumor effect of SSd, especially in the regulation of M2 macrophage polarization, and demonstrated that SSd may be a promising therapeutic agent in PDAC.

New treatment insights into pancreatic acinar cell carcinoma: case report and literature review

Pancreatic acinar cell carcinoma (PACC) is a rare pancreatic malignancy with unique clinical, molecular, and morphologic features. The long-term survival of patients with PACC is substantially better than that of patients with ductal adenocarcinoma of the pancreas. Surgical resection is considered the first choice for treatment; however, there is no standard treatment option for patients with inoperable disease. The patient with metastatic PACC reported herein survived for more than 5 years with various treatments including chemotherapy, radiotherapy, antiangiogenic therapy and combined immunotherapy.

CCR4 Blockade Diminishes Intratumoral Macrophage Recruitment and Augments Survival of Syngeneic Pancreatic Cancer-Bearing Mice

Pancreatic cancer is known for its tumor microenvironment (TME), which is rich in stromal and immune cells supporting cancer growth and therapy resistance. In particular, tumor-associated macrophages (TAMs) are known for their angiogenesis- and metastasis-promoting properties, which lead to the failure of conventional therapies for pancreatic cancer. Hence, treatment options targeting TAMs are needed. The C-C chemokine receptor type 4 (CCR4) is critical for immune cell recruitment into the TME, and in this paper we explore the effects of its genetic or immunotherapeutic blockade in pancreatic-cancer-bearing mice. Murine PDA6606 pancreatic cancer cells and murine peritoneal macrophages were used for in vitro migration assays. In vivo, a syngeneic, orthotropic pancreatic cancer model was established. Tumor growth and survival were monitored under prophylactic and therapeutic application of a CCR4 antagonist (AF-399/420/18025) in wildtype (CCR4^wt) and CCR4-knockout (CCR4^-/-) mice. Immune infiltration was monitored in tumor tissue sections and via flow cytometry of lysed tumors. PDA6606 cells induced less migration in CCR4^-/- than in CCR4^wt macrophages in vitro. Pancreatic TAM infiltration was higher, and survival was reduced in CCR4^wt mice compared to CCR4^-/- mice. Antagonizing CCR4 in wildtype mice revealed similar results as in CCR4^-/- mice without antagonization. Prophylactic CCR4 antagonist application in wildtype mice was more efficient than therapeutic antagonization. CCR4 seems to be critically involved in TAM generation and tumor progression in pancreatic cancer. CCR4 blockade may help prolong the relapse-free period after curative surgery in pancreatic cancer and improve prognosis.

Synthesis and electrochemical study of enzymatic graphene oxide-based nanocomposite as stable biosensor for determination of bevacizumab as a medicine in colorectal cancer in human serum and wastewater fluids

This work's goal was the fabrication of a graphene oxide-based nanocomposite biosensor for the determination of bevacizumab (BVZ) as a medicine for colorectal cancer in human serum and wastewater fluids. For the fabrication electrode, graphene oxide was electrodeposited on GCE (GO/GCE), and then DNA and monoclonal anti-bevacizumab antibodies were immobilized on the GO/GCE surface, respectively (Ab/DNA/GO/GCE). Structural characterization using XRD, SEM, and Raman spectroscopy confirmed the binding of DNA to GO nanosheets and the interaction of Ab with the DNA/GO array. Electrochemical characterization of Ab/DNA/GO/GCE using CV and DPV indicated immobilization of antibodies on DNA/GO/GCE and sensitive and selective behavior of modified electrodes for determination of BVZ. The linear range was obtained 10-1100 μg/mL, and the sensitivity and detection limit values were determined to be 0.14575 μA/μg.mL^-1 and 0.02 μg/mL, respectively. To verify the applicability of the planned sensor for determination of BVZ in human serum and wastewater fluid specimens, the outcomes of DPV measurements using Ab, DNA, GO, and GCE and the results of the Bevacizumab ELISA Kit for determination of BVZ in prepared real specimens showed good conformity between the outcomes of both analyses. Moreover, the proposed sensor showed considerable assay precision with recoveries ranging from 96.00% to 98.90% and acceptable relative standard deviations (RSDs) below 5.11%, illustrating sufficiently good sensor accuracy and validity in the determination of BVZ in prepared real specimens of human serum and wastewater fluids. These outcomes demonstrated the feasibility of the proposed BVZ sensor in clinical and environmental assay applications.

Chemoresistance in pancreatic ductal adenocarcinoma: Overcoming resistance to therapy

Pancreatic ductal adenocarcinoma (PDAC), a prominent cause of cancer deaths worldwide, is a highly aggressive cancer most frequently detected at an advanced stage that limits treatment options to systemic chemotherapy, which has provided only marginal positive clinical outcomes. More than 90% of patients with PDAC die within a year of being diagnosed. PDAC is increasing at a rate of 0.5-1.0% per year, and it is expected to be the second leading cause of cancer-related mortality by 2030. The resistance of tumor cells to chemotherapeutic drugs, which can be innate or acquired, is the primary factor contributing to the ineffectiveness of cancer treatments. Although many PDAC patients initially responds to standard of care (SOC) drugs they soon develop resistance caused partly by the substantial cellular heterogeneity seen in PDAC tissue and the tumor microenvironment (TME), which are considered key factors contributing to resistance to therapy. A deeper understanding of molecular mechanisms involved in PDAC progression and metastasis development, and the interplay of the TME in all these processes is essential to better comprehend the etiology and pathobiology of chemoresistance observed in PDAC. Recent research has recognized new therapeutic targets ushering in the development of innovative combinatorial therapies as well as enhancing our comprehension of several different cell death pathways. These approaches facilitate the lowering of the therapeutic threshold; however, the possibility of subsequent resistance development still remains a key issue and concern. Discoveries, that can target PDAC resistance, either alone or in combination, have the potential to serve as the foundation for future treatments that are effective without posing undue health risks. In this chapter, we discuss potential causes of PDAC chemoresistance and approaches for combating chemoresistance by targeting different pathways and different cellular functions associated with and mediating resistance.

New Treatment Options in Metastatic Pancreatic Cancer

Pancreatic cancer (PC) is the seventh leading cause of cancer death across the world. Poor prognosis of PC is associated with several factors, such as diagnosis at an advanced stage, early distant metastases, and remarkable resistance to most conventional treatment options. The pathogenesis of PC seems to be significantly more complicated than originally assumed, and findings in other solid tumours cannot be extrapolated to this malignancy. To develop effective treatment schemes prolonging patient survival, a multidirectional approach encompassing different aspects of the cancer is needed. Particular directions have been established; however, further studies bringing them all together and connecting the strengths of each therapy are needed. This review summarises the current literature and provides an overview of new or emerging therapeutic strategies for the more effective management of metastatic PC.

Identification of gene signatures related to hypoxia and angiogenesis in pancreatic cancer to aid immunotherapy and prognosis

Background

One of the most diverse tumors is pancreatic cancer (PC), which makes predicting the prognosis challenging. PC development is directly related to hypoxia, angiogenesis, and immunotherapy. It is still unclear how the three features are related.

Methods

The Genotype-Tissue Expression (GTEx) and the Cancer Genome Atlas (TCGA) database were employed to obtain sequencing data for healthy pancreatic tissues and PC tissues, respectively. According to the constructed hypoxic prognostic model (HPM) and angiogenic prognostic model (APM), 4 subtypes of PC were identified. Hypoxia and angiogenesis prognostic model (HAPM) was established based on differentially expressed genes (DEGs) between high-angiogenesis/high-hypoxia (HH) and low-angiogenesis/low-hypoxia (LL) subgroups. Base on the median risk score, PC patients were separated into high-risk and low-risk groups, and clinical traits, prognosis, percentage of immune cell infiltration, PD-1 expression, and the fraction of T-cell depletion were compared between the groups. Finally, the predictive accuracy of the tumor immune dysfunction and rejection (TIDE) and tumor inflammatory signature (TIS) models, as well as HAPM, was compared.

Result

We analyzed the mRNA sequencing data from 178 PC tissues and 171 normal pancreatic tissues to obtain 9527 DEGs. We discovered 200 genes linked with hypoxia and 36 genes involved with angiogenesis through the literature. We found the core genes related with hypoxia and angiogenesis in PC by intersecting the DEGs of the HH and LL subgroups with those of PC via WGCNA. IL-17 signaling pathway, ECM-receptor interactions, cytokine receptor interactions, etc. were all enriched in the Kyoto Encyclopedia of Genes and Genomes (KEGG) results of core genes. HAPM has good predictive efficiency, according to an evaluation of KM survival curves and ROC curves. The external dataset also validated the model’s ability to anticipate outcomes. Patients in the high- and low-risk groups were compared for PD1 expression and T-cell exclusion scores, which suggested that the model might be used to forecast which PC patients might benefit from immunotherapy.

Conclusions

The probable molecular processes connecting hypoxia and angiogenesis are described in this work, and a model is developed that may be utilized to forecast the prognosis for PC patients and the benefits of immunotherapy.

Single-cell RNA sequencing reveals the effects of chemotherapy on human pancreatic adenocarcinoma and its tumor microenvironment

The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDAC) is a complex ecosystem that drives tumor progression; however, in-depth single cell characterization of the PDAC TME and its role in response to therapy is lacking. Here, we perform single-cell RNA sequencing on freshly collected human PDAC samples either before or after chemotherapy. Overall, we find a heterogeneous mixture of basal and classical cancer cell subtypes, along with distinct cancer-associated fibroblast and macrophage subpopulations. Strikingly, classical and basal-like cancer cells exhibit similar transcriptional responses to chemotherapy and do not demonstrate a shift towards a basal-like transcriptional program among treated samples. We observe decreased ligand-receptor interactions in treated samples, particularly between TIGIT on CD8 + T cells and its receptor on cancer cells, and identify TIGIT as the major inhibitory checkpoint molecule of CD8 + T cells. Our results suggest that chemotherapy profoundly impacts the PDAC TME and may promote resistance to immunotherapy.

Combination, Modulation and Interplay of Modern Radiotherapy with the Tumor Microenvironment and Targeted Therapies in Pancreatic Cancer: Which Candidates to Boost Radiotherapy?

Pancreatic ductal adenocarcinoma cancer (PDAC) is a highly diverse disease with low tumor immunogenicity. PDAC is also one of the deadliest solid tumor and will remain a common cause of cancer death in the future. Treatment options are limited, and tumors frequently develop resistance to current treatment modalities. Since PDAC patients do not respond well to immune checkpoint inhibitors (ICIs), novel methods for overcoming resistance are being explored. Compared to other solid tumors, the PDAC's tumor microenvironment (TME) is unique and complex and prevents systemic agents from effectively penetrating and killing tumor cells. Radiotherapy (RT) has the potential to modulate the TME (e.g., by exposing tumor-specific antigens, recruiting, and infiltrating immune cells) and, therefore, enhance the effectiveness of targeted systemic therapies. Interestingly, combining ICI with RT and/or chemotherapy has yielded promising preclinical results which were not successful when translated into clinical trials. In this context, current standards of care need to be challenged and transformed with modern treatment techniques and novel therapeutic combinations. One way to reconcile these findings is to abandon the concept that the TME is a well-compartmented population with spatial, temporal, physical, and chemical elements acting independently. This review will focus on the most interesting advancements of RT and describe the main components of the TME and their known modulation after RT in PDAC. Furthermore, we will provide a summary of current clinical data for combinations of RT/targeted therapy (tRT) and give an overview of the most promising future directions.

Interplay between MAP kinases and tumor microenvironment: Opportunity for immunotherapy in pancreatic cancer

Pancreatic Ductal Adenocarcinoma (PDAC), commonly called pancreatic cancer, is aggressive cancer usually detected at a late stage, limiting treatment options with modest clinical responses. It is projected that by 2030, PDAC will be the second most common cause of cancer-related mortality in the United States. Drug resistance in PDAC is common and significantly affects patients' overall survival (OS). Oncogenic KRAS mutations are nearly uniform in PDAC, affecting over 90% of patients. However, effective drugs directed to target prevalent KRAS mutants in pancreatic cancer are not in clinical practice. Accordingly, efforts are continued on identifying alternative druggable target(s) or approaches to improve patient outcomes with PDAC. In most PDAC cases, the KRAS mutations turn-on the RAF-MEK-MAPK pathways, leading to pancreatic tumorigenesis. The MAPK signaling cascade (MAP4K→MAP3K→MAP2K→MAPK) plays a central role in the pancreatic cancer tumor microenvironment (TME) and chemotherapy resistance. The immunosuppressive pancreatic cancer TME is another unfavorable factor affecting the therapeutic efficacy of chemotherapy and immunotherapy. The immune checkpoint proteins (ICPs), including CTLA-4, PD-1, PD-L1, and PD-L2, are critical players in T cell dysfunction and pancreatic tumor cell growth. Here, we review the activation of MAPKs, a molecular trait of KRAS mutations and their impact on pancreatic cancer TME, chemoresistance, and expression of ICPs that could influence the clinical outcomes in PDAC patients. Therefore, understanding the interplay between MAPK pathways and TME could help to design rational therapy combining immunotherapy and MAPK inhibitors for pancreatic cancer treatment.

Clinical diagnosis and management of pancreatic cancer: Markers, molecular mechanisms, and treatment options

Pancreatic cancer (PC) is the third-leading cause of cancer deaths. The overall 5-year survival rate of PC is 9%, and this rate for metastatic PC is below 3%. However, the PC-induced death cases will increase about 2-fold by 2060. Many factors such as genetic and environmental factors and metabolic diseases can drive PC development and progression. The most common type of PC in the clinic is pancreatic ductal adenocarcinoma, comprising approximately 90% of PC cases. Multiple pathogenic processes including but not limited to inflammation, fibrosis, angiogenesis, epithelial-mesenchymal transition, and proliferation of cancer stem cells are involved in the initiation and progression of PC. Early diagnosis is essential for curable therapy, for which a combined panel of serum markers is very helpful. Although some mono or combined therapies have been approved by the United States Food and Drug Administration for PC treatment, current therapies have not shown promising outcomes. Fortunately, the development of novel immunotherapies, such as oncolytic viruses-mediated treatments and chimeric antigen receptor-T cells, combined with therapies such as neoadjuvant therapy plus surgery, and advanced delivery systems of immunotherapy will improve therapeutic outcomes and combat drug resistance in PC patients. Herein, the pathogenesis, molecular signaling pathways, diagnostic markers, prognosis, and potential treatments in completed, ongoing, and recruiting clinical trials for PC were reviewed.

Development of doped ZnO-based biomimicking and tumor-targeted nanotheranostics to improve pancreatic cancer treatment

Despite different nanomaterials were developed so far against cancer, their potential drawbacks are still scarcely considered. The off-target delivery of a therapeutic compound, as well as the non-specific uptake of these nanomaterials by healthy tissues or organs, and their potential immunogenicity are some of the major issues that still have to be faced prior to a successful clinical translation. This work aims to develop an innovative theranostic, biocompatible, and drug-loaded nanoconstruct based on Gadolinium-doped Zinc Oxide (ZnO-Gd) nanocrystals (NCs), focusing on one of the most lethal diseases, i.e., pancreatic cancer. The use of zinc oxide is motivated by the huge potential of this nanomaterial already demonstrated for in vitro and in vivo applications, while the Gadolinium doping confers magnetic properties useful for diagnostics. Furthermore, an innovative biomimetic shell is here used to coat the NCs: it is composed of a lipid bilayer made from extracellular vesicles (EVs) combined with other synthetic lipids and a peptide targeting the pancreatic tumor microenvironment. To complete the nanoconstruct therapeutic function, Gemcitabine, a first-line drug for pancreatic cancer treatment, was adsorbed on the ZnO-Gd NCs prior to the coating with the above-mentioned lipidic shell. The aim of this work is thus to strongly enhance the therapeutic capability of the final nanoconstruct, providing it with high biocompatibility, colloidal stability in biological media, efficient cargo loading and release properties, as well as active targeting for site-selective drug delivery. Furthermore, the magnetic properties of the ZnO-Gd NCs core can in future allow efficient in situ bioimaging capabilities based on Magnetic Resonance Imaging technique. The obtained nanoconstructs were tested on two different pancreatic cancer cell lines, i.e., BxPC-3 and the metastatic AsPC-1, proving high cell internalization levels, mediated by the targeting peptide exposed on the nanoconstruct. Cellular cytotoxicity assay performed on both cell lines dictated ~ 20% increased cell killing efficacy of Gemcitabine when delivered through the nanoconstruct rather than as a free drug. Taken together, our designed theranostic nanoconstruct can have a significant impact on the standard treatment of pancreatic cancer.

Advances in Engineered Biomaterials Targeting Angiogenesis and Cell Proliferation for Cancer Therapy

Antiangiogenic therapy in combination with chemotherapeutic agents is an effective strategy for cancer treatment. However, this combination therapy is associated with several challenges including non-specific biodistribution leading to systemic toxicity. Biomaterial-mediated codelivery of chemotherapeutic and anti-angiogenic agents can exploit their passive and active targeting abilities, leading to improved drug accumulation at the tumor site and therapeutic outcomes. In this review, we present the progress made in the field of engineered biomaterials for codelivery of chemotherapeutic and antiangiogenic agents. We present advances in engineering of liposome/hydrogel/micelle-based biomaterials for delivery of combination of anticancer and anti-angiogenesis drugs, or combination of anticancer and siRNA targeting angiogenesis, and targeted nanoparticles. We then present our perspective on developing strategies for targeting angiogenesis and cell proliferation for cancer therapy.

Hypoxia-Induced miR-210 Promotes Endothelial Cell Permeability and Angiogenesis via Exosomes in Pancreatic Ductal Adenocarcinoma

BACKGROUND

Exosomes have been proven to play important diagnostic, regulatory, or communication roles in tumorigenesis, tumor progression, or metastasis; in recent studies, lots of molecules, including miRNAs, were found to be aberrantly expressed in tumor exosomes and were correlated with tumor development. However, studies about the expression, relationship, or control mechanisms of miRNAs in exosomes in pancreatic ductal adenocarcinoma (PDAC) are scarce and urgently needed. The aim of this article was to identify and investigate abnormally expressed miRNAs in PDAC exosomes in vivo and in vitro.

METHODS

Microarray studies were used to detect aberrantly expressed miRNAs in PDAC exosomes, and miR-210 expression in cells or exosomes was further analyzed by qRT-PCR. Bioinformatics analyses, dual-luciferase assays, WB, and other assays were utilized to explore the miRNA molecular mechanisms. The living cell coculture model and immunofluorescence analysis were employed to image the communication between PDAC cells and endothelial cells. Other biological experiments in the study include a real-time intravital imaging system, EdU, transwell, xenograft models, and so on.

RESULTS

miR-210 is significantly expressed in PDAC exosomes and malignant cells. High miR-210 significantly facilitated tumor angiogenesis, cell invasion, and proliferation in PDAC cells. Further mechanistic detection revealed that miR-210 negatively regulated EFNA3 expression and participated in the PI3K/AKT/VEGFA or Wnt/Β-catenin/RHOA pathways, thus promoting tumor angiogenesis and cellular permeability. PDAC cells promote endothelial angiogenesis or permeability via miR-210 transmission by tumor exosomes. Exosomal miR-210 promotes PDAC progression in vivo. Further detection of PDAC plasma exosomal miR-210 suggests that exosomal miR-210 expression was high and significantly associated with vascular invasion and TNM stage and was an independent risk factor for PDAC overall survival.

CONCLUSIONS

PDAC cell-secreted exosomes could promote angiogenesis and cellular permeability of neighboring endothelial angiogenesis or permeability via miR-210 transmission. Exosomal miR-210 may play important roles in tumor biology and may be a useful prognostic marker in PDAC.

Ecoevolutionary biology of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC), the most common histological subtype of pancreatic cancer, is an aggressive disease predicted to be the 2nd cause of cancer mortality in the US by 2040. While first-line therapy has improved, 5-year overall survival has only increased from 5 to ∼10%, and surgical resection is only available for ∼20% of patients as most present with advanced disease, which is invariably lethal. PDAC has well-established highly recurrent mutations in four driver genes including KRAS, TP53, CDKN2A, and SMAD4. Unfortunately, these genetic drivers are not currently therapeutically actionable. Despite extensive sequencing efforts, few additional significantly recurrent and druggable drivers have been identified. In the absence of targetable mutations, chemotherapy remains the mainstay of treatment for most patients. Further, the role of the above driver mutations on PDAC initiation and early development is well-established. However, these mutations alone cannot account for PDAC heterogeneity nor discern early from advanced disease. Taken together, management of PDAC is an example highlighting the shortcomings of the current precision medicine paradigm. PDAC, like other malignancies, represents an ecoevolutionary process. Better understanding the disease through this lens can facilitate the development of novel therapeutic strategies to better control and cure PDAC. This review aims to integrate the current understanding of PDAC pathobiology into an ecoevolutionary framework.

Anlotinib exerts potent antileukemic activities in Ph chromosome negative and positive B-cell acute lymphoblastic leukemia via perturbation of PI3K/AKT/mTOR pathway

OBJECTIVES

Despite advances in the development of novel targeted therapies, the need for B-ALL alternative treatments has not been met. Anlotinib could blunt the proangiogenic activity of VEGFR, PDGFR, and FGFR, and has shown strong antitumor activities across multiple tumors. However, anlotinib cytotoxicity against B-ALL has not ever been evaluated, thus prompting us to initiate this study.

METHODS

Expression2Kinases program was used to identify potential treatment targets. Cell viability and apoptosis were determined by CCK-8 and Annexin V/PI staining kit, respectively. qRT-PCR and Western blotting were utilized to investigate the molecular mechanisms. In vivo antileukemia activity of Anlotinib was evaluated in a Ph⁺ B-ALL patient-Derived Xenograft (PDX) model.

RESULTS

Compared with treatment-naive B-ALL cases, RR B-ALL patients had higher activities in the VEGF/VEGFR signaling and the PI3K/AKT/mTOR pathway. Exposure of Ph^- and Ph⁺ B-ALL cells to anlotinib resulted in significant cell viability reduction, apoptosis enhancement, and cell cycle arrest at G2/M phase. Importantly, anlotinib treatment led to remarkably decreased leukemia burdens and extended the survival period in a Ph⁺ B-ALL PDX model. Blockade of the role of the proangiogenic mediators, comprising VEGFR2, PDGFR-beta, and FGFR3, played a critical role in the cytotoxicity of anlotinib against Ph^- and Ph⁺ B-ALL. Moreover, anlotinib dampened the activity of PI3K/AKT/mTOR pathway that resides in the convergence of the three mentioned proangiogenic signals.

CONCLUSION

This work provides impressive preclinical evidence of anlotinib against Ph^- and Ph⁺ B-ALL and raises a rationale for future clinical evaluation of this drug in the management of Ph^- and Ph⁺ B-ALL.

Autophagy: A Key Player in Pancreatic Cancer Progression and a Potential Drug Target

Pancreatic cancer is known to have the lowest survival outcomes among all major cancers, and unfortunately, this has only been marginally improved over last four decades. The innate characteristics of pancreatic cancer include an aggressive and fast-growing nature from powerful driver mutations, a highly defensive tumor microenvironment and the upregulation of advantageous survival pathways such as autophagy. Autophagy involves targeted degradation of proteins and organelles to provide a secondary source of cellular supplies to maintain cell growth. Elevated autophagic activity in pancreatic cancer is recognized as a major survival pathway as it provides a plethora of support for tumors by supplying vital resources, maintaining tumour survival under the stressful microenvironment and promoting other pathways involved in tumour progression and metastasis. The combination of these features is unique to pancreatic cancer and present significant resistance to chemotherapeutic strategies, thus, indicating a need for further investigation into therapies targeting this crucial pathway. This review will outline the autophagy pathway and its regulation, in addition to the genetic landscape and tumor microenvironment that contribute to pancreatic cancer severity. Moreover, this review will also discuss the mechanisms of novel therapeutic strategies that inhibit autophagy and how they could be used to suppress tumor progression.

Novel Drugs with High Efficacy against Tumor Angiogenesis

Angiogenesis is involved in physiological and pathological processes in the body. Tumor angiogenesis is a key factor associated with tumor growth, progression, and metastasis. Therefore, there is great interest in developing antiangiogenic strategies. Hypoxia is the basic initiating factor of tumor angiogenesis, which leads to the increase of vascular endothelial growth factor (VEGF), angiopoietin (Ang), hypoxia-inducible factor (HIF-1), etc. in hypoxic cells. The pathways of VEGF and Ang are considered to be critical steps in tumor angiogenesis. A number of antiangiogenic drugs targeting VEGF/VEGFR (VEGF receptor) or ANG/Tie2, or both, are currently being used for cancer treatment, or are still in various stages of clinical development or preclinical evaluation. This article aims to review the mechanisms of angiogenesis and tumor angiogenesis and to focus on new drugs and strategies for the treatment of antiangiogenesis. However, antitumor angiogenic drugs alone may not be sufficient to eradicate tumors. The molecular chaperone heat shock protein 90 (HSP90) is considered a promising molecular target. The VEGFR system and its downstream signaling molecules depend on the function of HSP90. This article also briefly introduces the role of HSP90 in angiogenesis and some HSP90 inhibitors.

Biological functions, mechanisms, and clinical significance of circular RNA in pancreatic cancer: a promising rising star

Pancreatic cancer (PC) is a highly malignant solid tumor with insidious onset and easy early metastasis. Despite tremendous efforts devoted to research in this field, the mechanisms underlying PC tumorigenesis and progression remain unclear. Additionally, robust biomarkers and satisfactory therapeutic strategies for clinical use in PC patients are still lacking. Circular RNAs (circRNAs) are a new type of non-coding RNA originating from precursor messenger RNAs, with a covalent continuous closed-loop structure, strong stability and high specificity. Accumulating evidence suggests that circRNAs may participate in PC development and progression. Abnormal expression of circRNAs in PC is considered a vital factor that affects tumor cell proliferation, migration, invasion, apoptosis, angiogenesis and drug resistance. In this review of relevant articles published in recent years, we describe the basic knowledge concerning circRNAs, including their classification, biogenesis, functions and research approaches. Moreover, the biological roles and clinical significance of circRNAs related to PC are discussed. Finally, we note the questions remaining from recent studies and anticipate that further investigations will address these gaps in knowledge in this field. In conclusion, we expect to provide insights into circRNAs as potential targets for specific PC diagnosis and treatment in the future.

Proteome Analysis of Pancreatic Tumors Implicates Extracellular Matrix in Patient Outcome

Pancreatic cancer remains a disease with unmet clinical needs and inadequate diagnostic, prognostic, and predictive biomarkers. In-depth characterization of the disease proteome is limited. This study thus aims to define and describe protein networks underlying pancreatic cancer and identify protein centric subtypes with clinical relevance. Mass spectrometry-based proteomics was used to identify and quantify the proteome in tumor tissue, tumor-adjacent tissue, and patient-derived xenografts (PDX)-derived cell lines from patients with pancreatic cancer, and tissues from patients with chronic pancreatitis. We identified, quantified, and characterized 11,634 proteins from 72 pancreatic tissue samples. Network focused analysis of the proteomics data led to identification of a tumor epithelium-specific module and an extracellular matrix (ECM)-associated module that discriminated pancreatic tumor tissue from both tumor adjacent tissue and pancreatitis tissue. On the basis of the ECM module, we defined an ECM-high and an ECM-low subgroup, where the ECM-high subgroup was associated with poor prognosis (median survival months: 15.3 vs. 22.9 months; log-rank test, P = 0.02). The ECM-high tumors were characterized by elevated epithelial-mesenchymal transition and glycolytic activities, and low oxidative phosphorylation, E2F, and DNA repair pathway activities. This study offers novel insights into the protein network underlying pancreatic cancer opening up for proteome precision medicine development.

Significance

Pancreatic cancer lacks reliable biomarkers for prognostication and treatment of patients. We analyzed the proteome of pancreatic tumors, nonmalignant tissues of the pancreas and PDX-derived cell lines, and identified proteins that discriminate between patients with good and poor survival. The proteomics data also unraveled potential novel drug targets.

Small Extracellular Vesicles: Key Forces Mediating the Development and Metastasis of Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer worldwide, and its incidence and mortality rates have been increasing annually in recent years. A variety of different small extracellular vesicles (sEVs) are important mediators of intercellular communication and have an important role in tumor metastasis and progression. The development and metastasis of CRC are closely linked to tumor-cell-derived sEVs, non-tumor-cell-derived sEVs, and intestinal-microbiota-derived sEVs. Numerous studies have shown that the tumor microenvironment (TME) is a key component in the regulation of CRC proliferation, development, and metastasis. These sEVs can create a TME conducive to CRC growth and metastasis by forming an immunosuppressive microenvironment, remodeling the extracellular matrix, and promoting tumor cell metabolism. Therefore, in this paper, we review the role of different types of sEVs in colorectal cancer development and metastasis. Furthermore, based on the properties of sEVs, we further discuss the use of sEVs as early biomarkers for colorectal cancer diagnosis and the potential for their use in the treatment of CRC.

3D bioprinted white adipose model for in vitro study of cancer-associated cachexia induced adipose tissue remodeling

Cancer-associated cachexia (CAC) is a complex metabolic and behavioral syndrome with multiple manifestations that involve systemic inflammation, weight loss, and adipose lipolysis. It impacts the quality of life of patients and is the direct cause of death in 20-30% of cancer patients. The severity of fat loss and adipose tissue remodeling negatively correlate with patients' survival outcomes. To address the mechanism of fat loss and design potential approaches to prevent the process, it will be essential to understand CAC pathophysiology through white adipose tissue models. In the present study, an engineered human white adipose tissue (eWAT) model based on three-dimensional (3D) bioprinting was developed and treated with pancreatic cancer cell-conditioned medium (CM) to mimic the status of CAC in vitro. We found that the CM treatment significantly increased the lipolysis and accumulation of the extracellular matrix (ECM). The 3D eWATs were further vascularized to study the influence of vascularization on lipolysis and CAC progression, which was largely unknown. Results demonstrated that CM treatment improved the angiogenesis of vascularized eWATs (veWATs), and veWATs demonstrated decreased glycerol release but increased Ucp1 expression, compared to eWATs. Many unique inflammatory cytokines (IL-8, CXCL-1, GM-CSF, etc) from the CM were detected and supposed to contribute to eWAT lipolysis, Ucp1 up-regulation, and ECM development. In response to CM treatment, eWATs also secreted inflammatory adipokines related to the metastatic ability of cancer, muscle atrophy, and vascularization (NGAL, CD54, IGFBP-2, etc). Our work demonstrated that the eWAT is a robust model for studying cachectic fat loss and the accompanying remodeling of adipose tissue. It is therefore a useful tool for future research exploring CAC physiologies and developing potential therapies.

Clinical Applications of Classical and Novel Biological Markers of Pancreatic Cancer

The incidence and prevalence of pancreatic adenocarcinoma have increased in recent years. Pancreatic cancer is the seventh leading cause of cancer death, but it is projected to become the second leading cause of cancer-related mortality by 2040. Most patients are diagnosed in an advanced stage of the disease, with very limited 5-year survival. The discovery of different tissue markers has elucidated the underlying pathophysiology of pancreatic adenocarcinoma and allowed stratification of patient risk at different stages and assessment of tumour recurrence. Due to the invasive capacity of this tumour and the absence of screening markers, new immunohistochemical and serological markers may be used as prognostic markers for recurrence and in the study of possible new therapeutic targets because the survival of these patients is low in most cases. The present article reviews the currently used main histopathological and serological markers and discusses the main characteristics of markers under development.

Fractal analysis improves tumour size measurement on computed tomography in pancreatic ductal adenocarcinoma: comparison with gross pathology and multi-parametric MRI

Objectives

Tumour size measurement is pivotal for staging and stratifying patients with pancreatic ductal adenocarcinoma (PDA). However, computed tomography (CT) frequently underestimates tumour size due to insufficient depiction of the tumour rim. CT-derived fractal dimension (FD) maps might help to visualise perfusion chaos, thus allowing more realistic size measurement.

Methods

In 46 patients with histology-proven PDA, we compared tumour size measurements in routine multiphasic CT scans, CT-derived FD maps, multi-parametric magnetic resonance imaging (mpMRI), and, where available, gross pathology of resected specimens. Gross pathology was available as reference for diameter measurement in a discovery cohort of 10 patients. The remaining 36 patients constituted a separate validation cohort with mpMRI as reference for diameter and volume.

Results

Median RECIST diameter of all included tumours was 40 mm (range: 18–82 mm). In the discovery cohort, we found significant (p = 0.03) underestimation of tumour diameter on CT compared with gross pathology (Δdiameter_3D = −5.7 mm), while realistic diameter measurements were obtained from FD maps (Δdiameter_3D = 0.6 mm) and mpMRI (Δdiameter_3D = −0.9 mm), with excellent correlation between the two (R² = 0.88). In the validation cohort, CT also systematically underestimated tumour size in comparison to mpMRI (Δdiameter_3D = −10.6 mm, Δvolume = −10.2 mL), especially in larger tumours. In contrast, FD map measurements agreed excellently with mpMRI (Δdiameter_3D = +1.5 mm, Δvolume = −0.6 mL). Quantitative perfusion chaos was significantly (p = 0.001) higher in the tumour rim (FD_rim = 4.43) compared to the core (FD_core = 4.37) and remote pancreas (FD_pancreas = 4.28).

Conclusions

In PDA, fractal analysis visualises perfusion chaos in the tumour rim and improves size measurement on CT in comparison to gross pathology and mpMRI, thus compensating for size underestimation from routine CT.

Key Points

• CT-based measurement of tumour size in pancreatic adenocarcinoma systematically underestimates both tumour diameter (Δdiameter = −10.6 mm) and volume (Δvolume = −10.2 mL), especially in larger tumours.

• Fractal analysis provides maps of the fractal dimension (FD), which enable a more reliable and size-independent measurement using gross pathology or multi-parametric MRI as reference standards.

• FD quantifies perfusion chaos—the underlying pathophysiological principle—and can separate the more chaotic tumour rim from the tumour core and adjacent non-tumourous pancreas tissue.

10Z‑Hymenialdisine inhibits angiogenesis by suppressing NF‑κB activation in pancreatic cancer cell lines

10Z-Hymenialdisine is a natural product derived from the marine sponge Axinella carteri. 10Z-Hymenialdisine has anti-inflammatory effects exerted through NF-κB; however, it is unclear whether 10Z-Hymenialdisine has anti-angiogenic effects in cancer cells. In the present study, both the anti-angiogenic and antimetastatic effects of this compound in pancreatic cancer were investigated. It was initially confirmed that 10Z-Hymenialdisine significantly inhibited the proliferation of pancreatic cancer cells. Next, using both reverse transcription-quantitative PCR and ELISA, it was demonstrated that 10Z-Hymenialdisine significantly suppressed the expression of VEGF and IL-8 mRNAs and proteins in pancreatic cancer. Immunohistochemical analysis revealed that 10Z-Hymenialdisine inhibited NF-κB activity in pancreatic cancer cell lines. It was also identified that 10Z-Hymenialdisine inhibited tube formation in EA.hy926 cells. In vivo, 10Z-Hymenialdisine significantly inhibited the growth of BxPC-3 pancreatic cancer cells that were subcutaneously injected into model mice. In conclusion, the present study demonstrated that 10Z-Hymenialdisine exerted anti-angiogenic effects by suppressing NF-κB activity and angiogenic factors, such as VEGF and IL-8, in pancreatic cancer cell lines. 10Z-Hymenialdisine has potential applications as a novel therapeutic agent for the treatment of pancreatic cancer.

Small extracellular vesicles: from mediating cancer cell metastasis to therapeutic value in pancreatic cancer

Pancreatic cancer is a highly malignant tumor and, is extremely difficult to diagnose and treat. Metastasis is one of the critical steps in the development of cancer and uses cell to cell communication to mediate changes in the microenvironment. Small extracellular vesicles (sEVs)-carry proteins, nucleic acids and other bioactive substances, and are important medium for communication between cells. There are two primary steps in sVEs-mediated metastasis: communication between pancreatic cancer cells and their surrounding microenvironment; and the communication between primary tumor cells and distant organ cells in distant organs that promotes angiogenesis, reshaping extracellular matrix, forming immunosuppressive environment and other ways to form appropriate pre-metastasis niche. Here, we explore the mechanism of localization and metastasis of pancreatic cancer and use sEVs as early biomarkers for the detection and treatment of pancreatic cancer. Video Abstract.

Role of Nrf2 in Pancreatic Cancer

Pancreatic tumors are a serious health problem with a 7% mortality rate worldwide. Inflammatory processes and oxidative stress play important roles in the development of pancreatic diseases/cancer. To maintain homeostasis, a balance between free radicals and the antioxidant system is essential. Nuclear Factor Erythroid 2-Related Factor 2/NFE2L2 (Nrf2) and its negative regulator Kelch-Like ECH-Associated Protein 1 (Keap1) provide substantial protection against damage induced by oxidative stress, and a growing body of evidence points to the canonical and noncanonical Nrf2 signaling pathway as a pharmacological target in the treatment of pancreatic diseases. In this review, we present updated evidence on the activation of the Nrf2 signaling pathway and its importance in pancreatic cancer. Our review covers potential modulators of canonical and noncanonical pathway modulation mechanisms that may have a positive effect on the therapeutic response. Finally, we describe some interesting recent discoveries of novel treatments related to the antioxidant system for pancreatic cancer, including natural or synthetic compounds with therapeutic properties.

Towards an updated view on the clinical management of pancreatic adenocarcinoma: Current and future perspectives

Pancreatic cancer has a dire prognosis and will represent the second leading cause of cancer death in the next 10 years. The multifactorial approach represents one of the main issues in controlling the extension of this neoplasm. In recent years, the characteristics of the tumor microenvironment, metastasis mechanisms and the relationship between immune system and neoplastic cells have been described, which has made it possible to understand the pathophysiology of pancreatic adenocarcinoma. Currently, there is a failure to provide an effective preventive method or early detection, so patients present with an advanced stage at the time of diagnosis. Despite numerous efforts, little progress has been made in clinical outcome and in improving survival in long term. Therefore, in the recent years, diverse diagnostic tests, treatments and possible approaches have been developed in the fields of radiotherapy, chemotherapy and surgery to find a combination of them that improves life expectancy in patients diagnosed with pancreatic cancer. At the moment, numerous clinical trials are being conducted to evaluate preventive diagnostic procedures such as serological markers or perfecting available imaging tests. On the other hand, implementation of immunotherapy is being studied in a neoplasm that has lagged in the application of this procedure since present possible treatments do not substantially improve quality of life. Therefore, the purpose of our study is to summarize the main progresses that have been made in the diagnosis, treatment and screening of this disease, explaining the limitations that have been observed and analyzing future prospects in the management of this illness.

The Heterogeneity of the Tumor Microenvironment as Essential Determinant of Development, Progression and Therapy Response of Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is commonly diagnosed at advanced stages and most anti-cancer therapies have failed to substantially improve prognosis of PDAC patients. As a result, PDAC is still one of the deadliest tumors. Tumor heterogeneity, manifesting at multiple levels, provides a conclusive explanation for divergent survival times and therapy responses of PDAC patients. Besides tumor cell heterogeneity, PDAC is characterized by a pronounced inflammatory stroma comprising various non-neoplastic cells such as myofibroblasts, endothelial cells and different leukocyte populations which enrich in the tumor microenvironment (TME) during pancreatic tumorigenesis. Thus, the stromal compartment also displays a high temporal and spatial heterogeneity accounting for diverse effects on the development, progression and therapy responses of PDAC. Adding to this heterogeneity and the impact of the TME, the microbiome of PDAC patients is considerably altered. Understanding this multi-level heterogeneity and considering it for the development of novel therapeutic concepts might finally improve the dismal situation of PDAC patients. Here, we outline the current knowledge on PDAC cell heterogeneity focusing on different stromal cell populations and outline their impact on PDAC progression and therapy resistance. Based on this information, we propose some novel concepts for treatment of PDAC patients.

Mechanisms of Cancer Cell Death: Therapeutic Implications for Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a type of cancer that is strongly associated with poor prognosis and short median survival times. In stark contrast to the progress seen in other cancer types in recent decades, discoveries of new treatments in PDAC have been few and far between and there has been little improvement in overall survival (OS). The difficulty in treating this disease is multifactorial, contributed to by late presentation, difficult access to primary tumour sites, an 'immunologically cold' phenotype, and a strong tendency of recurrence likely driven by cancer stem cell (CSC) populations. Furthermore, apparently contrasting roles of tumour components (such as fibrotic stroma) and intracellular pathways (such as autophagy and TGFβ) have made it difficult to distinguish beneficial from detrimental drug targets. Despite this, progress has been made in the field, including the determination of mFOLFIRINOX as the standard-of-care adjuvant therapy and the discovery of KRASG12C mutant inhibitors. Moreover, new research, as outlined in this review, has highlighted promising new approaches including the targeting of the tumour microenvironment, enhancement of immunotherapies, epigenetic modulation, and destruction of CSCs.

Targeting the Stroma in the Management of Pancreatic Cancer

Pancreatic cancer (PC) presents extremely aggressive tumours and is associated with poor survival. This is attributed to the unique features of the tumour microenvironment (TME), which is known to create a dense stromal formation and poorly immunogenic condition. In particular, the TME of PC, including the stromal cells and extracellular matrix, plays an essential role in the progression and chemoresistance of PC. Consequently, several promising agents that target key components of the stroma have already been developed and are currently in multiple stages of clinical trials. Therefore, the authors review the latest available evidence on novel stroma-targeting approaches, highlighting the potential impact of the stroma as a key component of the TME in PC.

Fluorinated thiazolidinol drives autophagic cell death in pancreatic cancer cells via AMPK activation and perturbation of critical sentinels of oncogenic signaling

Pancreatic cancer is one of the most malignant cancers around the world. The co-occurrence of mutation in KRAS and p53 makes it highly aggressive, proliferative, metastatic, and resistant to apoptotic cell death. Therefore, there is a need to trigger an alternate mechanism of cancer cell death in apoptosis-resistant pancreatic cancer. Autophagic cell death could be an alternate viable option for treatment in such cases. Thus, the identification of small molecules as autophagy modulators with potent anticancer efficacy would be of great importance in pancreatic cancer. The present study investigates fluorinated thiazolidionol (FTZ) driven autophagy modulation, underlying mechanism, and regulation of critical sentinels of oncogenic signaling in pancreatic cancer cells. We identified that FTZ triggered autophagic cell death in pancreatic cancer cells, independent of apoptosis evidenced by an increase in cytoplasmic vacuoles formation, autophagy flux, LC3-II expression, and p62 degradation. Further, the crucial events of apoptosis i.e., Caspase-3 activation and PARP cleavage, were not observed, indicating the non-occurrence of apoptotic cell death. Moreover, FTZ was able to activate AMPK and suppress PI3k/Akt/mTOR as well as MEK/ERK, the key oncogenic signaling pathways in cancer cells. Furthermore, treatment with FTZ suppressed migration, invasion, and angiogenesis in pancreatic cancer cells. Studies in vivo revealed significant regression of tumors by FTZ in nude mice model. Overall, our study demonstrates that FTZ induces autophagic cell death in pancreatic cancer cells independent of apoptosis, which is accompanied by AMPK activation and suppression of critical sentinels of oncogenic signaling in pancreatic cancer cells.

Escin inhibits angiogenesis by suppressing interleukin‑8 and vascular endothelial growth factor production by blocking nuclear factor‑κB activation in pancreatic cancer cell lines

Pancreatic cancer (PaCa) is one of the most aggressive types of cancer. Thus, the development of new and more effective therapies is urgently required. Escin, a pentacyclic triterpenoid from the horse chestnut, has been reported to exhibit antitumor potential by reducing cell proliferation and blocking the nuclear factor‑κB (NF‑κB) signaling pathway in several types of cancer. Our previous study reported that NF‑κB enhanced the secretion of interleukin (IL)‑8 and vascular endothelial growth factor (VEGF), thereby inducing angiogenesis in PaCa cell lines. In the present study, it was examined whether escin inhibited angiogenesis by blocking NF‑κB activation in PaCa. It was initially confirmed that escin, at concentrations >10 µM, significantly inhibited the proliferation of several PaCa cell lines. Next, using immunocytochemical staining, it was found that escin inhibited the nuclear translocation of NF‑κB. Furthermore, ELISA confirmed that NF‑κB activity in the escin‑treated PaCa cells was significantly inhibited and reverse transcription‑quantitative PCR showed that the mRNA expression levels of tumor necrosis factor‑α‑induced IL‑8 and VEGF were significantly suppressed following escin treatment in the PaCa cell lines. ELISA also showed that escin decreased the secretion of IL‑8 and VEGF from the PaCa cells. Furthermore, tube formation in immortalized human endothelial cells was inhibited following incubation with the supernatants from escin‑treated PaCa cells. These results indicated that escin inhibited angiogenesis by reducing the secretion of IL‑8 and VEGF by blocking NF‑κB activity in PaCa. In conclusion, escin could be used as a novel molecular therapy for PaCa.

Multi-Omics Analysis of Anlotinib in Pancreatic Cancer and Development of an Anlotinib-Related Prognostic Signature

Aberrant regulation of angiogenesis involves in the growth and metastasis of tumors, but angiogenesis inhibitors fail to improve overall survival of pancreatic cancer patients in previous phase III clinical trials. A comprehensive knowledge of the mechanism of angiogenesis inhibitors against pancreatic cancer is helpful for clinical purpose and for the selection of patients who might benefit from the inhibitors. In this work, multi-omics analyses (transcriptomics, proteomics, and phosphoproteomics profiling) were carried out to delineate the mechanism of anlotinib, a novel angiogenesis inhibitor, against pancreatic cancer cells. The results showed that anlotinib exerted noteworthy cytotoxicity on pancreatic cancer cells. Multi-omics analyses revealed that anlotinib had a profound inhibitory effect on ribosome, and regulated cell cycle, RNA metabolism and lysosome. Based on the multi-omics results and available data deposited in public databases, an anlotinib-related gene signature was further constructed to identify a subgroup of pancreatic cancer patients who had a dismal prognosis and might be responsive to anlotinib.

Glutamine Synthetase as a Therapeutic Target for Cancer Treatment

The significance of glutamine in cancer metabolism has been extensively studied. Cancer cells consume an excessive amount of glutamine to facilitate rapid proliferation. Thus, glutamine depletion occurs in various cancer types, especially in poorly vascularized cancers. This makes glutamine synthetase (GS), the only enzyme responsible for de novo synthesizing glutamine, essential in cancer metabolism. In cancer, GS exhibits pro-tumoral features by synthesizing glutamine, supporting nucleotide synthesis. Furthermore, GS is highly expressed in the tumor microenvironment (TME) and provides glutamine to cancer cells, allowing cancer cells to maintain sufficient glutamine level for glutamine catabolism. Glutamine catabolism, the opposite reaction of glutamine synthesis by GS, is well known for supporting cancer cell proliferation via contributing biosynthesis of various essential molecules and energy production. Either glutamine anabolism or catabolism has a critical function in cancer metabolism depending on the complex nature and microenvironment of cancers. In this review, we focus on the role of GS in a variety of cancer types and microenvironments and highlight the mechanism of GS at the transcriptional and post-translational levels. Lastly, we discuss the therapeutic implications of targeting GS in cancer.