FOLFIRINOX versus gemcitabine for metastatic pancreatic cancer

Efficacy of first-line combination therapies versus gemcitabine monotherapy for advanced pancreatic cancer: a systematic review and network meta-analysis

Various first-line gemcitabine-based or fluorouracil-based combination regimens were approved in patients with advanced pancreatic cancer. Recent randomized clinical trials (RCTs) have investigated chemotherapy backbones in combination with novel investigational drugs, including chemotherapy agents or targeted drugs. However, the comparative efficacy of these different combination therapies remains limited. This systematic review and network meta-analysis aimed to assess the efficacy of first-line combination therapies for advanced pancreatic cancer. The study included 46 RCTs with 10,499 patients and 47 distinct regimens, using data sources from MEDLINE, EMBASE, Cochrane Clinical Trials, and ClinicalTrials.gov from January 1, 2010 to April 23, 2024. The primary outcomes were overall survival (OS) and progression-free survival (PFS), while secondary outcomes included overall response rate (ORR) and disease control rate (DCR). The analysis revealed that gemcitabine+nab-paclitaxel (GA), GA with platinum and fluorouracil (GA+Plat+FU), gemcitabine with fluorouracil (G+FU), G+Plt+FU, and FOLFIRINOX were associated with superior OS and PFS compared to gemcitabine monotherapy. Triplet or quadruplet polychemotherapy combinations, such as GA+Plat+FU, G+Plt+FU, and FOLFIRINOX, demonstrated better OS benefit with hazard ratios of 0.42 (95% CI, 0.26-0.68), 0.41 (95% CI, 0.24-0.71), and 0.58 (95% CI, 0.48-0.71), respectively, compared to doublet regimens like GA and G+FU, which had hazard ratios of 0.70 (95% CI, 0.59-0.82) and 0.82 (95% CI, 0.72-0.95), respectively. Notably, no targeted drugs, monoclonal antibodies, or other medications showed improved survival when added to chemotherapy backbones. These findings support the use of gemcitabine-based or fluorouracil-based triplet or quadruplet regimens for better survival outcomes in patients with advanced pancreatic cancer. Further research is warranted to explore the potential benefits of adding chemotherapy agents, such as fluorouracil, to the GA doublet regimen.

The impact of metastatic sites on survival Rates and predictors of extended survival in patients with metastatic pancreatic cancer

BACKGROUND OBJECTIVES

The aim of this study was to determine the role of site-specific metastatic patterns over time and assess factors associated with extended survival in metastatic PDAC. Half of all patients with pancreatic ductal adenocarcinoma (PDAC) present with metastatic disease. The site of metastasis plays a crucial role in clinical decision making due to its prognostic value.

METHODS

We examined 56,757 stage-IV PDAC patients from the National Cancer Database (2016-2019), categorizing them by metastatic site: multiple, liver, lung, brain, bone, carcinomatosis, or other. The site-specific prognostic value was assessed using log-rank tests while time-varying effects were assessed by Aalen's linear hazards model. Factors associated with extended survival (>3years) were assessed with logistic regression.

RESULTS

Median overall survival (mOS) in patients with distant lymph node-only metastases (9.0 months) and lung-only metastases (8.1 months) was significantly longer than in patients with liver-only metastases (4.6 months, p < 0.001). However, after six months, the metastatic site lost prognostic value. Logistic regression identified extended survivors (3.6 %) as more likely to be younger, Hispanic, privately insured, Charlson-index <2, having received chemotherapy, or having undergone primary or distant site surgery (all p < 0.001).

CONCLUSION

While synchronous liver metastases are associated with worse outcomes than lung-only and lymph node-only metastases, this predictive value is diminished after six months. Therefore, treatment decisions beyond this time should not primarily depend on the metastatic site. Extended survival is possible in a small subset of patients with favorable tumor biology and good conditional status, who are more likely to undergo aggressive therapies.

Understanding, diagnosing, and treating pancreatic cancer from the perspective of telomeres and telomerase

Telomerase is associated with cellular aging, and its presence limits cellular lifespan. Telomerase by preventing telomere shortening can extend the number of cell divisions for cancer cells. In adult pancreatic cells, telomeres gradually shorten, while in precancerous lesions of cancer, telomeres in cells are usually significantly shortened. At this time, telomerase is still in an inactive state, and it is not until before and after the onset of cancer that telomerase is reactivated, causing cancer cells to proliferate. Methylation of the telomerase reverse transcriptase (TERT) promoter and regulation of telomerase by lactate dehydrogenase B (LDHB) is the mechanism of telomerase reactivation in pancreatic cancer. Understanding the role of telomeres and telomerase in pancreatic cancer will help to diagnose and initiate targeted therapy as early as possible. This article reviews the role of telomeres and telomerase as biomarkers in the development of pancreatic cancer and the progress of research on telomeres and telomerase as targets for therapeutic intervention.

Comparison of survival for metastatic pancreatic cancer patients treated with CPI-613 versus resected borderline-resectable pancreatic cancer patients

INTRODUCTION

Treatment of advanced pancreatic adenocarcinoma remains suboptimal. Therapeutic agents with a novel mechanism of action are desperately needed; one such novel agent is CPI-613 targets. We here analyze the outcomes of 20 metastatic pancreatic cancer patients treated with CPI-613 and FOLFIRINOX in our institution and evaluate their outcomes to borderline-resectable patients treated with curative surgery.

METHODS

A post hoc analysis was performed of the phase I CPI-613 trial data (NCT03504423) comparing survival outcomes to borderline-resectable cases treated with curative resection at the same institution. Survival was measured by overall survival (OS) for all study cases and disease-free survival (DFS) for resected cases with progression-free survival for CPI-613 cases.

RESULTS

There were 20 patients in the CPI-613 cohort and 60 patients in the surgical cohort. Median follow-up times were 441 and 517 days for CPI-613 and resected cases, respectively. There was no difference in survival times between CPI-613 and resected cases with a mean OS of 1.8 versus 1.9 year (p = 0.779) and mean PFS/DFS of 1.4 versus 1.7 years (p = 0.512). There was also no difference in 3-year survival rates for OS (hazard ratio [HR] = 1.063, 95% confidence interval [CI] 0.302-3.744, p = 0.925) or DFS/PFS (HR = 1.462, 95% CI 0.285-7.505, p = 0.648).

CONCLUSION

The first study to evaluate the survival between metastatic patients treated with CPI-613 versus borderline-resectable cases undergoing curative resection. Analysis revealed no significant differences in survival outcomes between the cohorts. Study results are suggestive that there may be potential utility with the addition of CPI-613 to potentially resectable pancreatic adenocarcinoma, although additional research with more comparable study groups are required.

PANoptosis-related molecular subtype and prognostic model associated with the immune microenvironment and individualized therapy in pancreatic cancer

Background

PANoptosis is an inflammatory type of programmed cell death regulated by PANopotosome. Mounting evidence has shown that PANoptosis could be involved in cancer pathogenesis and the tumor immune microenvironment. Nevertheless, there have been no studies on the mechanism of PANoptosis on pancreatic cancer (PC) pathogenesis.

Methods

We downloaded the data on transcriptomic and clinical features of PC patients from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus databases. Additionally, the data on copy number variation (CNV), methylation and somatic mutations of genes in 33 types of cancers were obtained from TCGA. Next, we identified the PANoptosis-related molecular subtype using the consensus clustering analysis, and constructed and validated the PANoptosis-related prognostic model using LASSO and Cox regression analyses. Moreover, RT-qPCR was performed to determine the expression of genes involved in the model.

Results

We obtained 66 PANoptosis-related genes (PANRGs) from published studies. Of these, 24 PC-specific prognosis-related genes were identified. Pan-cancer analysis revealed complex genetic changes, including CNV, methylation, and mutation in PANRGs were identified in various cancers. By consensus clustering analysis, PC patients were classified into two PANoptosis-related patterns: PANcluster A and B. In PANcluster A, the patient prognosis was significantly worse compared to PANcluster B. The CIBERSORT algorithm showed a significant increase in the infiltration of CD8⁺ T cells, monocytes, and naïve B cells, in patients in PANcluster B. Additionally, the infiltration of macrophages, activated mast cells, and dendritic cells were higher in patients in PANcluster A. Patients in PANcluster A were more sensitive to erlotinib, selumetinib and trametinib, whereas patients in PANcluster B were highly sensitive to irinotecan, oxaliplatin and sorafenib. Moreover, we constructed and validated the PANoptosis-related prognostic model to predict the patient's survival. Finally, the GEPIA and Human Protein Atlas databases were analyzed, and RT-qPCR was performed. Compared to normal tissues, a significant increase in CXCL10 and ITGB6 (associated with the model) expression was observed in PC tissues.

Conclusion

We first identified the PANoptosis-related molecular subtypes and established a PANoptosis-related prognostic model for predicting the survival of patients with PC. These results would aid in exploring the mechanisms of PANoptosis in PC pathogenesis.

Efficacy and Safety of Chemotherapy in Elderly Patients with Unresectable Pancreatic Cancer

BACKGROUND/AIMS

The incidence of pancreatic cancer (PC) is gradually increasing among elderly individuals, but there are insufficient clinical data on elderly individuals. To determine the efficacy and safety of chemotherapy, we compared the. the outcomes of elderly patients with unresectable PC.

METHODS

We enrolled patients aged 75 years or older diagnosed with PC from 1 January 2010 to 30 November 2021. Propensity score matching (PSM) was used to reduce the heterogeneity of the study population. For efficacy evaluation, the median overall survival (OS) was estimated for the chemotherapy and nonchemotherapy groups. Chemotherapy tolerability evaluations were also investigated.

RESULTS

The study included 115 patients, 47 of whom received chemotherapy and 68 who did not. After PSM, compared with the nonchemotherapy group, the chemotherapy group had more myocardial infarctions (14.6 vs. 0.0%, p < 0.001) and chronic obstructive pulmonary disease (4.4 vs. 0.0%, p = 0.043). The primary endpoint, median OS, was significantly different in the with vs. without chemotherapy groups (203 vs. 106 days, p = 0.013). In the chemotherapy group, 10 patients (21.3%) discontinued treatment due to adverse events. However, there were no reports of death due to severe adverse events.

CONCLUSIONS

This study demonstrated that chemotherapy improved median OS among elderly patients. These data could support the use of chemotherapy for elderly patients with unresectable PC.

hENT1's role in adjuvant intra-arterial gemcitabine-based chemotherapy for resectable pancreatic cancer patients

BACKGROUND

We aimed to verify the role of hENT1 as a prognostic predictor for patients with resectable pancreatic ductal adenocarcinoma (PDAC) who underwent radical resection followed by intra-arterial infusion of gemcitabine-based regimen.

METHODS

We collected surgical samples from 102 patients with resectable PDAC who received radical resection followed by intra-arterial infusion of gemcitabine-based regimen. The hENT1 expression with the help of immunohistochemistry was conducted using formalin-fixed and paraffin embedded tissues. The Kaplan-Meier analyses and Cox regression were used to evaluate the mortality hazard associated with the discrepancy between strong and weak of hENT1 expression. Patients' clinical and pathological characteristics were compared between the two groups, then the role of hENT1 as a prognostic predictor was further explored.

RESULTS

A total of 102 patients were included to assess the hENT1 expression. 50 patients were classified into high hENT1 expression group, the other 52 patients were attributed into low hENT1 expression group. High hENT1 expression was related to a significantly improved overall survival (OS) (p = 0.014) and disease-free survival (DFS) (p = 0.004). Both univariate (p = 0.001) and multivariate analyses (p < 0.001) indicated that high hENT1 expression was related to a decreased mortality.

CONCLUSIONS

High expression of hENT1 is positive prognostic factor for adjuvant intra-arterial gemcitabine-based chemotherapy in resectable PDAC.

A population-based study of synchronous distant metastases and prognosis in patients with PDAC at initial diagnosis

Objective

Cancer of the pancreas is a life-threatening condition and has a high distant metastasis (DM) rate of over 50% at diagnosis. Therefore, this study aimed to determine whether patterns of distant metastases correlated with prognosis in pancreatic ductal adenocarcinoma (PDAC) with metastatic spread, and build a novel nomogram capable of predicting the 6, 12, 18-month survival rate with high accuracy.

Methods

We analyzed data from the Surveillance, Epidemiology, and End Results (SEER) database for cases of PDAC with DM. Kaplan-Meier analysis, log-rank tests and Cox-regression proportional hazards model were used to assess the impact of site and number of DM on the cancer-specific survival (CSS) and over survival (OS). A total of 2709 patients with DM were randomly assigned to the training group and validation group in a 7:3 ratio. A nomogram was constructed by the dependent risk factors which were determined by multivariate Cox-regression analysis. An assessment of the discrimination and ability of the prediction model was made by measuring AUC, C-index, calibration curve and decision curve analysis (DCA). In addition, we collected 98 patients with distant metastases at the time of initial diagnosis from Ningbo University Affiliated LiHuili Hospital to verify the efficacy of the prediction model.

Results

There was a highest incidence of liver metastases from pancreatic cancer (2387,74.36%), followed by lung (625,19.47%), bone (190,5.92%), and brain (8,0.25%). The prognosis of liver metastases differed from that of lung metastases, and the presence of multiple organ metastases was associated with poorer prognosis. According to univariate and multivariate Cox-regression analyses, seven factors (i.e., diagnosis age, tumor location, grade of tumor differentiation, T-stage, receipt of surgery, receipt of chemotherapy status, presence of multiple organ metastases) were included in our nomogram model. In internal and external validation, the ROC curves, C-index, calibration curves and DCA were calculated, which confirmed that this nomogram can precisely predict prognosis of PDAC with DM.

Conclusion

Metastatic PDAC patients with liver metastases tended to have a worse prognosis than those with lung metastases. The number of DM had significant effect on the overall survival rate of metastatic PDAC. This study had a high prediction accuracy, which was helpful clinicians to analyze the prognosis of PDAC with DM and implement individualized diagnosis and treatment.

Identification of the γ-glutamyl cycle as a novel therapeutic target and 5-oxoproline as a new biomarker for diagnosing pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignant solid tumours, and abnormal metabolic reprogramming in the tumour microenvironment is regarded as an important contributor to its pathogenesis.

OBJECTIVES

As there is an urgency to identify new targets based on the metabolic features that are highly refractory to PDAC treatment, this study aimed to identify suitable therapeutic targets for PDAC.

METHODS

In this study, gene set enrichment and Kyoto Encyclopedia of Genes and Genomes analyses were performed on 163 PDAC tissue samples and 165 normal pancreatic tissue samples from The Cancer Genome Atlas and Genotype-Tissue Expression databases to identify alterations in critical metabolites that may contribute to PDAC pathogenesis. Furthermore, ultra-performance liquid chromatography-tandem mass spectrometry was performed to identify significant metabolic pathways between 24 pairs of tumour and adjacent non-tumour tissues and between serum samples from PDAC patients and healthy donors.

RESULTS

Fifty-one tissue metabolites and 26 serum metabolites were altered in PDAC. Among them, those in the γ-glutamyl cycle were the most substantially changed, and 5-oxoproline was the biomarker of PDAC with the most significantly decreased levels.

CONCLUSIONS

The γ-glutamyl cycle and 5-oxoproline might be potential biomarkers and therapeutic targets to improve the diagnosis, therapy, and prognosis of PDAC.

Expression of cartilage oligomeric matrix protein in periampullary adenocarcinoma is associated with pancreatobiliary-type morphology, higher levels of fibrosis and immune cell exclusion

Cartilage oligomeric matrix protein (COMP) is an emerging regulator of tumor progression. The aim of this study was to evaluate the expression of COMP in periampullary adenocarcinoma with respect to prognostic value for survival and relapse, levels of fibrosis and infiltrating immune cells. COMP expression was evaluated using immunohistochemistry in primary tumors and subsets of paired lymph node metastases in tissue microarrays including 175 patients with periampullary adenocarcinoma. Collagen content was assessed with Sirius Red-Fast Green staining. High COMP levels were detected in cancer cells and in stroma, in 46% and 57% of the patients, respectively. High COMP expression was strongly associated with more aggressive pancreatobiliary-type (PB-type) compared to intestinal-type tumors (p < .0001). Importantly, high expression of COMP correlated with the exclusion of cytotoxic T-cells from the cancer cell compartment of the tumors, particularly in PB-type tumors. Higher levels of fibrosis measured by the density of collagen fibers correlated with high COMP levels in both cancer cells and stroma. This in turn could lead to exclusion of cytotoxic T-cells from accessing the cancer cells, a recognized immunotherapy resistance mechanism. Targeting COMP could therefore be considered as a novel therapeutic strategy in PB-type periampullary adenocarcinoma.

Mechanisms of PDAC subtype heterogeneity and therapy response

Pancreatic ductal adenocarcinoma (PDAC) is clinically challenging due to late diagnosis and resistance to therapy. Two major PDAC subtypes have been defined based on malignant epithelial cell gene expression profiles; the basal-like/squamous subtype is associated with a worse prognosis and therapeutic resistance as opposed to the classical subtype. Subtype specification is not binary, consistent with plasticity of malignant cell phenotype. PDAC heterogeneity and plasticity reflect partly malignant cell-intrinsic transcriptional and epigenetic regulation. However, the stromal and immune compartments of the tumor microenvironment (TME) also determine disease progression and therapy response. It is evident that integration of intrinsic and extrinsic factors can dictate subtype heterogeneity, and thus, delineating the pathways involved can help to reprogram PDAC towards a classical/druggable subtype.

Epidemiology and prognostic analysis of patients with pancreatic signet ring cell carcinoma: a population-based study

Background

Pancreatic signet ring cell carcinoma (PSRCC) is a rare tumour subtype with poorly understood epidemiological characteristics and prognosis. We attempted to comprehensively characterise the epidemiology and survival outcomes of PSRCC.

Methods

Patients diagnosed with PSRCC between 2000 and 2018 were identified using Surveillance, Epidemiology and End Results Stat 8.3.9.2 software. Age-adjusted incidence and survival were calculated. Survival curves were plotted using the Kaplan–Meier method, and the differences between survival curves were compared using the log-rank test. Cox proportional hazards models were used to evaluate factors that independently predict overall survival. The primary analysis was a complete case analysis; multiple imputations were employed in a sensitivity analysis.

Results

We identified 585 eligible patients with PSRCC. The overall annual incidence from 2000 to 2018 was 0.349 (95% CI, 0.321–0.379) per million population. The incidence increased significantly in patients over 55 years of age and peaked at about 80 years of age (2.12 per million). Males and Black patients had the highest incidence. The observed survival rates at 1, 2 and 5 years were 20.1, 8.3 and 3.4%, respectively. Survival analysis revealed that primary surgery and chemotherapy are effective treatments for patients with PSRCC (P < 0.05). According to multivariate Cox regression analysis, early stage and receiving surgery and chemotherapy were favourable factors (P < 0.05). Similar conclusions were drawn from the interpolated data.

Conclusions

PSRCC is a highly malignant tumour that predominates in elderly, male and Black patients. The prognosis is poor with a 5-year survival rate of 3.4%; however, multivariate analysis and adjusted models accounting for missing data revealed that early diagnosis, surgery and chemotherapy are effective in improving the prognosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02543-z.

A New Manganese Superoxide Dismutase Mimetic Improves Oxaliplatin-Induced Neuropathy and Global Tolerance in Mice

Reactive oxygen species (ROS) are produced by every aerobic cell during mitochondrial oxidative metabolism as well as in cellular response to xenobiotics, cytokines, and bacterial invasion. Superoxide Dismutases (SOD) are antioxidant proteins that convert superoxide anions (O2•−) to hydrogen peroxide (H2O2) and dioxygen. Using the differential in the level of oxidative stress between normal and cancer cells, SOD mimetics can show an antitumoral effect and prevent oxaliplatin-induced peripheral neuropathy. New Pt(IV) conjugate prodrugs (OxPt-x-Mn1C1A (x = 1, 1-OH, 2)), combining oxaliplatin and a Mn SOD mimic (MnSODm Mn1C1A) with a covalent link, were designed. Their stability in buffer and in the presence of sodium ascorbate was studied. In vitro, their antitumoral activity was assessed by the viability and ROS production of tumor cell lines (CT16, HCT 116, KC) and fibroblasts (primary culture and NIH 3T3). In vivo, a murine model of colorectal cancer was created with subcutaneous injection of CT26 cells in Balb/c mice. Tumor size and volume were measured weekly in four groups: vehicle, oxaliplatin, and oxaliplatin associated with MnSODm Mn1C1A and the bis-conjugate OxPt-2-Mn1C1A. Oxaliplatin-induced peripheral neuropathy (OIPN) was assessed using a Von Frey test reflecting chronic hypoalgesia. Tolerance to treatment was assessed with a clinical score including four items: weight loss, weariness, alopecia, and diarrhea. In vitro, Mn1C1A associated with oxaliplatin and Pt(IV) conjugates treatment induced significantly higher production of H2O2 in all cell lines and showed a significant improvement of the antitumoral efficacy compared to oxaliplatin alone. In vivo, the association of Mn1C1A to oxaliplatin did not decrease its antitumoral activity, while OxPt-2-Mn1C1A had lower antitumoral activity than oxaliplatin alone. Mn1C1A associated with oxaliplatin significantly decreased OIPN and also improved global clinical tolerance of oxaliplatin. A neuroprotective effect was observed, associated with a significantly improved tolerance to oxaliplatin without impairing its antitumoral activity.

Comparative Proteomic Analysis Identifies Key Metabolic Regulators of Gemcitabine Resistance in Pancreatic Cancer

Pancreatic adenocarcinoma (PDAC) is highly refractory to treatment. Standard-of-care gemcitabine (Gem) provides only modest survival benefits, and development of Gem resistance (GemR) compromises its efficacy. Highly GemR clones of Gem-sensitive MIAPaCa-2 cells were developed to investigate the molecular mechanisms of GemR and implemented global quantitative differential proteomics analysis with a comprehensive, reproducible ion-current-based MS1 workflow to quantify ∼6000 proteins in all samples. In GemR clone MIA-GR8, cellular metabolism, proliferation, migration, and 'drug response' mechanisms were the predominant biological processes altered, consistent with cell phenotypic alterations in cell cycle and motility. S100 calcium binding protein A4 was the most downregulated protein, as were proteins associated with glycolytic and oxidative energy production. Both responses would reduce tumor proliferation. Upregulation of mesenchymal markers was prominent, and cellular invasiveness increased. Key enzymes in Gem metabolism pathways were altered such that intracellular utilization of Gem would decrease. Ribonucleoside-diphosphate reductase large subunit was the most elevated Gem metabolizing protein, supporting its critical role in GemR. Lower Ribonucleoside-diphosphate reductase large subunit expression is associated with better clinical outcomes in PDAC, and its downregulation paralleled reduced MIAPaCa-2 proliferation and migration and increased Gem sensitivity. Temporal protein-level Gem responses of MIAPaCa-2 versus GemR cell lines (intrinsically GemR PANC-1 and acquired GemR MIA-GR8) implicate adaptive changes in cellular response systems for cell proliferation and drug transport and metabolism, which reduce cytotoxic Gem metabolites, in DNA repair, and additional responses, as key contributors to the complexity of GemR in PDAC. These findings additionally suggest targetable therapeutic vulnerabilities for GemR PDAC patients.

Axon guidance receptor ROBO3 modulates subtype identity and prognosis via AXL-associated inflammatory network in pancreatic cancer

Metastatic pancreatic cancer (PDAC) has a poor clinical outcome with a 5-year survival rate below 3%. Recent transcriptome profiling of PDAC biopsies has identified 2 clinically distinct subtypes - the "basal-like" (BL) subtype with poor prognosis and therapy resistance compared with the less aggressive and drug-susceptible "classical" (CLA) subtype. However, the mechanistic events and environmental factors that promote the BL subtype identity are not very clear. Using preclinical models, patient-derived xenografts, and FACS-sorted PDAC patient biopsies, we report here that the axon guidance receptor, roundabout guidance receptor 3 (ROBO3), promotes the BL metastatic program via a potentially unique AXL/IL-6/phosphorylated STAT3 (p-STAT3) regulatory axis. RNA-Seq identified a ROBO3-mediated BL-specific gene program, while tyrosine kinase profiling revealed AXL as the key mediator of the p-STAT3 activation. CRISPR/dCas9-based ROBO3 silencing disrupted the AXL/p-STAT3 signaling axis, thereby halting metastasis and enhancing therapy sensitivity. Transcriptome analysis of resected patient tumors revealed that AXLhi neoplastic cells associated with the inflammatory stromal program. Combining AXL inhibitor and chemotherapy substantially restored a CLA phenotypic state and reduced disease aggressiveness. Thus, we conclude that a ROBO3-driven hierarchical network determines the inflammatory and prometastatic programs in a specific PDAC subtype.

Understanding Tricky Cellular and Molecular Interactions in Pancreatic Tumor Microenvironment: New Food for Thought

Pancreatic ductal adenocarcinoma (PDAC) represents 90% of all pancreatic cancer cases and shows a high mortality rate among all solid tumors. PDAC is often associated with poor prognosis, due to the late diagnosis that leads to metastasis development, and limited efficacy of available treatments. The tumor microenvironment (TME) represents a reliable source of novel targets for therapy, and even if many of the biological interactions among stromal, immune, and cancer cells that populate the TME have been studied, much more needs to be clarified. The great limitation in the efficacy of current standard chemoterapy is due to both the dense fibrotic inaccessible TME barrier surrounding cancer cells and the immunological evolution from a tumor-suppressor to an immunosuppressive environment. Nevertheless, combinatorial therapies may prove more effective at overcoming resistance mechanisms and achieving tumor cell killing. To achieve this result, a deeper understanding of the pathological mechanisms driving tumor progression and immune escape is required in order to design rationale-based therapeutic strategies. This review aims to summarize the present knowledge about cellular interactions in the TME, with much attention on immunosuppressive functioning and a specific focus on extracellular matrix (ECM) contribution.

A Novel Small Molecular Prostaglandin Receptor EP4 Antagonist, L001, Suppresses Pancreatic Cancer Metastasis

Metastatic pancreatic cancer remains a major clinical challenge, emphasizing the urgent need for the exploitation of novel therapeutic approaches with superior response. In this study, we demonstrate that the aberrant activation of prostaglandin E₂ (PGE₂) receptor 4 (EP4) is a pro-metastatic signal in pancreatic cancer. To explore the therapeutic role of EP4 signaling, we developed a potent and selective EP4 antagonist L001 with single-nanomolar activity using a panel of cell functional assays. EP4 antagonism by L001 effectively repressed PGE₂-elicited cell migration and the invasion of pancreatic cancer cells in a dose-dependent manner. Importantly, L001 alone or combined with the chemotherapy drug gemcitabine exhibited remarkably anti-metastasis activity in a pancreatic cancer hepatic metastasis model with excellent tolerability and safety. Mechanistically, EP4 blockade by L001 abrogated Yes-associated protein 1 (YAP)-driven pro-metastatic factor expression in pancreatic cancer cells. The suppression of YAP’s activity was also observed upon L001 treatment in vivo. Together, these findings support the notions that EP4–YAP signaling axis is a vital pro-metastatic pathway in pancreatic cancer and that EP4 inhibition with L001 may deliver a therapeutic benefit for patients with metastatic pancreatic cancer.

Pancreatic Ductal Adenocarcinoma Cortical Mechanics and Clinical Implications

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest cancers due to low therapeutic response rates and poor prognoses. Majority of patients present with symptoms post metastatic spread, which contributes to its overall lethality as the 4th leading cause of cancer-related deaths. Therapeutic approaches thus far target only one or two of the cancer specific hallmarks, such as high proliferation rate, apoptotic evasion, or immune evasion. Recent genomic discoveries reveal that genetic heterogeneity, early micrometastases, and an immunosuppressive tumor microenvironment contribute to the inefficacy of current standard treatments and specific molecular-targeted therapies. To effectively combat cancers like PDAC, we need an innovative approach that can simultaneously impact the multiple hallmarks driving cancer progression. Here, we present the mechanical properties generated by the cell’s cortical cytoskeleton, with a spotlight on PDAC, as an ideal therapeutic target that can concurrently attack multiple systems driving cancer. We start with an introduction to cancer cell mechanics and PDAC followed by a compilation of studies connecting the cortical cytoskeleton and mechanical properties to proliferation, metastasis, immune cell interactions, cancer cell stemness, and/or metabolism. We further elaborate on the implications of these findings in disease progression, therapeutic resistance, and clinical relapse. Manipulation of the cancer cell’s mechanical system has already been shown to prevent metastasis in preclinical models, but it has greater potential for target exploration since it is a foundational property of the cell that regulates various oncogenic behaviors.

Potential Role of Exosomes in the Chemoresistance to Gemcitabine and Nab-Paclitaxel in Pancreatic Cancer

In recent years, a growing number of studies have evaluated the role of exosomes in pancreatic ductal adenocarcinoma cancer (PDAC) demonstrating their involvement in a multitude of pathways, including the induction of chemoresistance. The aim of this review is to present an overview of the current knowledge on the role of exosomes in the resistance to gemcitabine and nab-paclitaxel, which are two of the most commonly used drugs for the treatment of PDAC patients. Exosomes are vesicular cargos that transport multiple miRNAs, mRNAs and proteins from one cell to another cell and some of these factors can influence specific determinants of gemcitabine activity, such as the nucleoside transporter hENT1, or multidrug resistance proteins involved in the resistance to paclitaxel. Additional mechanisms underlying exosome-mediated resistance include the modulation of apoptotic pathways, cellular metabolism, or the modulation of oncogenic miRNA, such as miR-21 and miR-155. The current status of studies on circulating exosomal miRNA and their possible role as biomarkers are also discussed. Finally, we integrated the preclinical data with emerging clinical evidence, showing how the study of exosomes could help to predict the resistance of individual tumors, and guide the clinicians in the selection of innovative therapeutic strategies to overcome drug resistance.

Arterial Administration of DNA Crosslinking Agents with Restraint of Homologous Recombination Repair by Intravenous Low-Dose Gemcitabine Is Effective for Locally Advanced Pancreatic Cancer

Simple Summary

Pancreatic cancer is considered incurable, and most cases are detected in the advanced stages. Establishing a new, effective interventional treatment for advanced pancreatic cancer is a pressing issue. Pretreatment with gemcitabine had a restraining effect on the homologous DNA recombination repair (HRR) of DNA crosslinking, inhibiting the function of Rad51, of which expression is found to be increased in pancreatic cancer. The aim of our prospective study was to assess the potential value of the arterial administration of DNA crosslinking agents after intravenous administration of low-dose gemcitabine for patients with advanced pancreatic cancer. We confirmed, among forty-five patients with unresectable advanced pancreatic cancer, that a patient subgroup of locally advanced pancreatic cancer (LAPC, 10 patients) who underwent these treatment courses successively more than twice in the first 6 months had 33 months of overall survival, 31 months of local progression free survival, and a complete response of 40%. This treatment can be a new treatment option for LAPC.

Abstract

(1) Background: Pretreatment by Rad51-inhibitory substances such as gemcitabine followed by arterial chemotherapy using antineoplastic agents causing DNA crosslink might be more beneficial for patients with locally advanced pancreatic cancers than conventional treatments. The efficacy of arterial administration of DNA crosslinking agents with pretreatment of intravenous low-dose gemcitabine for patients with unresectable locally advanced or metastatic pancreatic cancer (LAPC or MPC) is evaluated. (2) Methods: A single-arm, single-center, institutional review board-approved prospective study was conducted between 2005 and 2015. Forty-five patients (23 LAPC, 22 MPC) were included. Patients received a weekly low dose of gemcitabine intravenously for three weeks followed by arterial administration of mitomycin C and epirubicin hydrochloride at tumor-supplying arteries on the fifth or sixth week. This treatment course was repeated at 1.5-to-2-month intervals. Overall survival (OS), local progression-free survival (LPFS), and therapeutic response were evaluated. LAPC or MPC were divided according to treatment compliance, excellent or poor (1 or 2), to subgroups L1, L2, M1, and M2. (3) Results: OS of LAPC and MPC were 23 months and 13 months, respectively. The OS of LAPC with excellent treatment compliance (subgroup L1, 10 patients) was 33 months with 31 months of LPFS, and four patients (40%) had a complete response (CR). The OS of the L1 subgroup was significantly longer than those of other subgroups L2, M1, and M2, which were 17 months, 17 months, and 8 months, respectively. As Grade 3 adverse effects, severe bone marrow suppression, interstitial pneumonitis, and hemolytic uremic syndrome were observed in six (13.0%), three (6.5%), and three (6.5%) patients, respectively. (4) Conclusions: Arterial DNA crosslinking with the systemic restraint of homologous recombination repair can be a new treatment option for LAPC.

Individualized Prediction of Survival Benefits of Pancreatectomy Plus Chemotherapy in Patients With Simultaneous Metastatic Pancreatic Cancer

Background

Metastatic pancreatic cancer (mPC) is a highly lethal malignancy with poorer survival. However, chemotherapy alone was unable to maintain long-term survival. This study aimed to evaluate the individualized survival benefits of pancreatectomy plus chemotherapy (PCT) for mPC.

Methods

A total of 4546 patients with mPC from 2004 to 2015 were retrieved from the Surveillance, Epidemiology, and End Results database. The survival curve was calculated using the Kaplan-Meier method and differences in survival curves were tested using log-rank tests. Cox proportional hazards regression analyses were performed to evaluate the prognostic value of involved variables. A new nomogram was constructed to predict overall survival based on independent prognosis factors. The performance of the nomogram was measured by concordance index, calibration plot, and area under the receiver operating characteristic curve.

Results

Compared to pancreatectomy or chemotherapy alone, PCT can significantly improve the prognosis of patients with mPC. In addition, patients with well/moderately differentiated tumors, age ≤66 years, tumor size ≤42 mm, or female patients were more likely to benefit from PCT. Multivariate analysis showed that age at diagnosis, sex, marital status, grade, tumor size, and treatment were independent prognostic factors. The established nomogram has a good ability to distinguish and calibrating.

Conclusion

PCT can prolong survival in some patients with mPC. Our nomogram can individualize predict OS of pancreatectomy combined with chemotherapy in patients with concurrent mPC.

Cholesterol biosynthesis inhibitor RO 48‑8071 inhibits pancreatic ductal adenocarcinoma cell viability by deactivating the JNK and ERK/MAPK signaling pathway

The morbidity and mortality of pancreatic cancer have been continuously increasing, causing seven deaths per 100,000 individuals/year. At present, effective therapies are severely lacking, thus, highlighting the importance of developing novel therapeutic approaches. The present study aimed to investigate the inhibitory roles of the 2,3-oxidosqualene cyclase inhibitor, RO 48-8071 (RO), on pancreatic ductal adenocarcinoma. RO was used to treat the pancreatic cancer cell line (PANC-1) in vitro to examine the effects of RO on cell viability, as well as to determine its potential molecular mechanism. Moreover, experiments in a xenograft model of subcutaneous tumors generated by injecting PANC-1 cells hypodermically into nude mice were performed to observe the inhibition of RO on tumor growth. It was found that RO inhibited PANC-1 cell viability when treatment was given for 24, 48 and 72 h. The in vivo study demonstrated that RO markedly inhibited subcutaneous tumor growth in nude mice. Further studies revealed that RO could induce cell cycle arrest in the G₁ phase by regulating p27, cyclin B1 and cyclin E expression to inhibit PANC-1 cell viability. Moreover, RO inactivated the JNK and ERK MAPK signaling pathway by decreasing the phosphorylation levels of JNK and ERK. Collectively, the present study demonstrated that RO served anti-pancreatic cancer roles in vitro and in vivo, which may provide new ideas and facilitate the development of novel treatment options for pancreatic cancer.

Autophagy-mediated negative feedback attenuates the oncogenic activity of YAP in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is the most lethal malignancy in humans, and new therapeutic targets are urgently needed. Yes-associated protein (YAP) plays a significant role in cancer progression. Autophagy is also closely associated with various human cancers. However, the interplay between YAP and autophagy in PDAC remains poorly understood. In this study, we found that YAP was upregulated and activated in PDAC. Further analysis revealed that there is a YAP-autophagy feedback loop in pancreatic cancer. Mechanistically, YAP activates autophagy by promoting Atg5 transcription via TEAD1-mediated binding, while autophagy negatively regulates YAP through autophagic degradation. The hyperactivation of YAP in PDAC unbalances the YAP-autophagy circuit and promotes cancer progression. Inhibition of autophagy enhances the oncogenic activity of YAP in PDAC. The autophagy activator rapamycin promotes the antitumor effect of verteporfin, a YAP inhibitor. Therefore, our study elucidated the interaction between YAP and autophagy in PDAC and our results suggest that targeting the YAP-autophagy circuit may be a new therapeutic strategy for pancreatic cancer.

Establishment of Pancreatobiliary Cancer Zebrafish Avatars for Chemotherapy Screening

Background: Cancers of the pancreas and biliary tree remain one of the most aggressive oncological malignancies, with most patients relying on systemic chemotherapy. However, effective biomarkers to predict the best therapy option for each patient are still lacking. In this context, an assay able to evaluate individual responses prior to treatment would be of great value for clinical decisions. Here we aimed to develop such a model using zebrafish xenografts to directly challenge pancreatic cancer cells to the available chemotherapies. Methods: Zebrafish xenografts were generated from a Panc-1 cell line to optimize the pancreatic setting. Pancreatic surgical resected samples, without in vitro expansion, were used to establish zebrafish patient-derived xenografts (zAvatars). Upon chemotherapy exposure, zAvatars were analyzed by single-cell confocal microscopy. Results: We show that Panc-1 zebrafish xenografts are able to reveal tumor responses to both FOLFIRINOX and gemcitabine plus nanoparticle albumin-bound (nab)-paclitaxel in just 4 days. Moreover, we established pancreatic and ampullary zAvatars with patient-derived tumors representative of different histological types. Conclusion: Altogether, we provide a short report showing the feasibility of generating and analyzing with single-cell resolution zAvatars from pancreatic and ampullary cancers, with potential use for future preclinical studies and personalized treatment.

Immune Subtypes Based on Immune-Related lncRNA: Differential Prognostic Mechanism of Pancreatic Cancer

Pancreatic cancer consists one of tumors with the highest degree of malignancy and the worst prognosis. To date, immunotherapy has become an effective means to improve the prognosis of patients with pancreatic cancer. Long non-coding RNAs (lncRNAs) have also been associated with the immune response. However, the role of immune-related lncRNAs in the immune response of pancreatic cancer remains unclear. In this study, we identified immune-related lncRNA pairs through a new combinatorial algorithm, and then clustered and deeply analyzed the immune characteristics and functional differences between subtypes. Subsequently, the prognostic model of 3 candidate lncRNA pairs was determined by multivariate COX analysis. The results showed significant prognostic differences between the C1 and C2 subtypes, which may be due to the differential infiltration of CTL and NK cells and the activation of tumor-related pathways. The prognostic model of the 3 lncRNA pairs (AC244035.1_vs._AC063926.1, AC066612.1_vs._AC090124.1, and AC244035.1_vs._LINC01885) was established, which exhibits stable and effective prognostic prediction performance. These 3 lncRNA pairs may regulate the anti-tumor effect of immune cells through ion channel pathways. In conclusion, our research demonstrated the panoramic differences in immune characteristics between subtypes and stable prognostic models, and identified new potential targets for immunotherapy.

Therapeutic Potential of Targeting Stromal Crosstalk-Mediated Immune Suppression in Pancreatic Cancer

The stroma-rich, immunosuppressive microenvironment is a hallmark of pancreatic ductal adenocarcinoma (PDA). Tumor cells and other cellular components of the tumor microenvironment, such as cancer associated fibroblasts, CD4+ T cells and myeloid cells, are linked by a web of interactions. Their crosstalk not only results in immune evasion of PDA, but also contributes to pancreatic cancer cell plasticity, invasiveness, metastasis, chemo-resistance, immunotherapy-resistance and radiotherapy-resistance. In this review, we characterize several prevalent populations of stromal cells in the PDA microenvironment and describe how the crosstalk among them drives and maintains immune suppression. We also summarize therapeutic approaches to target the stroma. With a better understanding of the complex cellular and molecular networks in PDA, strategies aimed at sensitizing PDA to chemotherapy or immunotherapy through re-programing the tumor microenvironment can be designed, and in turn lead to improved clinical treatment for pancreatic cancer patients.

In Vivo Assessment of Hypoxia Levels in Pancreatic Tumors Using a Dual-Modality Ultrasound/Photoacoustic Imaging System

Noninvasive anatomical and functional imaging has become an essential tool to evaluate tissue oxygen saturation dynamics in preclinical or clinical studies of hypoxia. Our dual-wavelength technique for photoacoustic (PA) imaging based on the differential absorbance spectrum of oxyhemoglobin (oxy-Hb) and deoxyhemoglobin (deoxy-Hb) can quantify tissue oxygen saturation using the intrinsic contrast property. PA imaging of tissue oxygen saturation can be used to monitor tumor-related hypoxia, which is a particularly relevant functional parameter of the tumor microenvironment that has a strong influence on tumor aggressiveness. The simultaneous acquisition of anatomical and functional information using dual-modality ultrasound (US) and PA imaging technology enhances the preclinical applicability of the method. Here, the developed dual-modality US/PA system was used to measure relative tissue oxygenation using the dual-wavelength technique. Tissue oxygen saturation was quantified in a pancreatic tumor mouse model. The differences in tissue oxygenation were detected by comparing pancreatic samples from normal and tumor-bearing mice at various time points after implantation. The use of an in vivo pancreatic tumor model revealed changes in hypoxia at various stages of tumor growth. The US/PA imaging data positively correlated with the results of immunohistochemical staining for hypoxia. Thus, our dual-modality US/PA imaging system can be used to reliably assess and monitor hypoxia in pancreatic tumor mouse models. These findings enable the use of a combination of US and PA imaging to acquire anatomical and functional information on tumor growth and to evaluate treatment responses in longitudinal preclinical studies.

Overcoming the Tumor Microenvironmental Barriers of Pancreatic Ductal Adenocarcinomas for Achieving Better Treatment Outcomes

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive disease with the lowest survival rate among all solid tumors. The lethality of PDAC arises from late detection and propensity of the tumor to metastasize and develop resistance against chemo and radiation therapy. A highly complex tumor microenvironment composed of dense stroma, immune cells, fibroblast, and disorganized blood vessels, is the main obstacle to current PDAC therapy. Despite the tremendous success of immune checkpoint inhibitors (ICIs) in cancers, PDAC remains one of the poorest responders of ICIs therapy. The immunologically "cold" phenotype of PDAC is attributed to the low mutational burden, high infiltration of myeloid-derived suppressor cells and T-regs, contributing to a significant immunotherapy resistance mechanism. Thus, the development of innovative strategies for turning immunologically "cold" tumor into "hot" ones is an unmet need to improve the outcome of PDAC ICIs therapies. Other smart strategies, such as nanomedicines, sonic Hedgehog inhibitor, or smoothened inhibitor, are discussed to enhance chemotherapeutic agents' efficiency by disrupting the PDAC stroma. This review highlights the current challenges and various preclinical and clinical strategies to overcome current PDAC therapy difficulties, thus significantly advancing PDAC research knowledge.

Synergistic Pharmacodynamic Effects of Gemcitabine and Fibroblast Growth Factor Receptor Inhibitors on Pancreatic Cancer Cell Cycle Kinetics and Proliferation

Median survival of pancreatic ductal adenocarcinoma cancer (PDAC) is 6 months, with 9% 5-year survival. Standard-of-care gemcitabine (Gem) provides only modest survival benefits, and combination therapies integrating novel targeted agents could improve outcomes. Fibroblast growth factor (FGF) receptors (FGFRs) play important roles in PDAC growth and invasion. Therefore, FGFR inhibitors (FGFRi) merit further investigation. Efficacy of Gem combined with NVP-BGJ398, a pan-FGFRi, was investigated in multiple PDAC cell lines exposed to the drugs alone and combined. Cell cycle distribution and cell numbers were quantified over time. Two pharmacodynamic models were developed to investigate Gem/BGJ398 interactions quantitatively: a drug-mediated cell proliferation/death model, and a drug-perturbed cell cycle progression model. The models captured temporal changes in cell numbers, cell cycle progression, and cell death during drug exposure. Simultaneous fitting of all data provided reasonable parameter estimates. Therapeutic efficacy was then evaluated in a PDAC mouse model. Compared with Gem alone, combined Gem + FGFRi significantly downregulated ribonucleotide-diphosphate reductase large subunit 1 (RRM1), a gemcitabine resistance (GemR) biomarker, suggesting the FGFRi inhibited GemR emergence. The cell proliferation/death pharmacodynamic model estimated the drug interaction coefficient ψ death = 0.798, suggesting synergistic effects. The mechanism-based cell cycle progression model estimated drug interaction coefficient ψ cycle = 0.647, also suggesting synergy. Thus, FGFR inhibition appears to synergize with Gem in PDAC cells and tumors by sensitizing cells to Gem-mediated inhibition of proliferation and cell cycle progression. SIGNIFICANCE STATEMENT: An integrated approach of quantitative modeling and experimentation was employed to investigate the nature of fibroblast growth factor receptor inhibitor (FGFRi)/gemcitabine (Gem) interaction, and to identify mechanisms by which FGFRi exposure reverses Gem resistance in pancreatic cancer cells. The results show that FGFRi interacts synergistically with Gem to sensitize pancreatic cancer cells and tumors to Gem-mediated inhibition of proliferation and cell cycle progression. Thus, addition of FGFRi to standard-of-care Gem treatment could be a clinically deployable approach to enhance therapeutic benefit to pancreatic cancer patients.

Recognition and pathological features of periampullary region adenocarcinoma with an indeterminable origin

Determination of the primary tumor in periampullary region carcinomas can be difficult, and the pathological assessment and clinicopathological characteristics remain elusive. In this study, we investigated the current recognition and practices for periampullary region adenocarcinoma with an indeterminable origin among expert pathologists through a cognitive survey. Simultaneously, we analyzed a prospective collection of cases with an indeterminable primary tumor diagnosed from 2008 to 2018 to elucidate their clinicopathological features. All cases with pathological indeterminable primary tumors were reported and discussed in a clinicopathological conference to elucidate if it was possible to distinguish the primary tumor clinically and pathologically. From the cognitive survey, over 85% of the pathologists had experienced cases with indeterminable primary tumors; however, 70% of the cases was reported as pancreatic cancer without definitive grounds. Interpretation of the main tumor mass varied, and no standardized method was developed to determine the primary tumor. During a prospective study, 42 of the 392 periampullary carcinoma cases (10.7%) were considered as tumors with a pathological indeterminable origin. After the clinicopathological conferences, 21 (5.4%) remained indeterminable and were considered final indeterminable cases. Histological studies showed that the tumors spread along both the bile duct and main pancreatic duct; this was the most representative finding of the final indeterminable cases. This study is the first to elucidate and recognize the current clinicopathological features of periampullary region adenocarcinomas with an indeterminable origin. Adequate assessment of primary tumors in periampullary region carcinomas will help to optimize epidemiological data of pancreatic and bile duct cancer.

A polymeric micellar drug delivery system developed through a design of Experiment approach improves pancreatic tumor accumulation of calcipotriol and paclitaxel

The aim of this study was to develop optimal micelles loaded with calcipotriol (Cal) and paclitaxel (PTX) for the treatment of pancreatic ductal adenocarcinoma (PDAC) using a Design of Experiment (DOE) approach. The central composite design (CCD), a type of DOE was used to tune the size and drug release properties of the drug-loaded micelles. This approach yielded optimal Cal and PTX co-loaded micelles (M-Cal/PTX) with size of 40-100 nm, a polydispersity index (PDI) of 0.25 and a zeta potential (ζ) of − 6.2 ± 0.8 mV. When evaluated in vitro, drug release from the micelles showed a biphasic pattern. The initial release, defined as the cumulative 2-hr drug release was less than 25% in all relevant media. This phase was followed by a gradual release with less than 80% of drugs released after 5 days. In vivo, the micelles prolonged the apparent biological half-life of Cal by more than 3 times and a marginal increase for PTX in an orthotopic mouse model of PDAC. The micelle-encapsulated drugs showed extended tumor accumulation when compared to non-encapsulated Cal and PTX at equivalent dose levels. Future studies on the antitumor activity of this novel dual drug payload delivery system are warranted.

KRAS, A Prime Mediator in Pancreatic Lipid Synthesis through Extra Mitochondrial Glutamine and Citrate Metabolism

Kirsten rat sarcoma viral oncogene homolog (KRAS)-driven pancreatic cancer is very lethal, with a five-year survival rate of <9%, irrespective of therapeutic advances. Different treatment modalities including chemotherapy, radiotherapy, and immunotherapy demonstrated only marginal efficacies because of pancreatic tumor specificities. Surgery at the early stage of the disease remains the only curative option, although only in 20% of patients with early stage disease. Clinical trials targeting the main oncogenic driver, KRAS, have largely been unsuccessful. Recently, global metabolic reprogramming has been identified in patients with pancreatic cancer and oncogenic KRAS mouse models. The newly reprogrammed metabolic pathways and oncometabolites affect the tumorigenic environment. The development of methods modulating metabolic reprogramming in pancreatic cancer cells might constitute a new approach to its therapy. In this review, we describe the major metabolic pathways providing acetyl-CoA and NADPH essential to sustain lipid synthesis and cell proliferation in pancreatic cancer cells.

ABO Blood Group and Risk of Pancreatic Carcinogenesis in Intraductal Papillary Mucinous Neoplasms

BACKGROUND

ABO blood group has been associated with risks of various malignancies, including pancreatic cancer. No study has evaluated the association of ABO blood group with incidence of pancreatic carcinogenesis during follow-up of patients with intraductal papillary mucinous neoplasms (IPMN).

METHODS

Among 3,164 patients diagnosed with pancreatic cysts at the University of Tokyo (Tokyo, Japan) from 1994 through 2019, we identified 1,815 patients with IPMN with available data on ABO blood group. We studied the association of ABO blood group with incidence of pancreatic carcinoma, overall and by carcinoma types [IPMN-derived carcinoma or concomitant pancreatic ductal adenocarcinoma (PDAC)]. Utilizing competing-risks proportional hazards models, we estimated subdistribution hazard ratios (SHR) for incidence of pancreatic carcinoma with adjustment for potential confounders, including cyst characteristics.

RESULTS

During 11,518 person-years of follow-up, we identified 97 patients diagnosed with pancreatic carcinoma (53 with IPMN-derived carcinoma and 44 with concomitant PDAC). Compared with patients with blood group O, patients with blood groups A, B, and AB had multivariable SHRs (95% confidence intervals) for pancreatic carcinoma of 2.25 (1.25-4.07; P = 0.007), 2.09 (1.08-4.05; P = 0.028), and 1.17 (0.43-3.19; P = 0.76), respectively. We observed no differential association of ABO blood group with pancreatic carcinoma incidence by carcinoma types.

CONCLUSIONS

In this large long-term study, patients with IPMN with blood group A or B appeared to be at higher risk of pancreatic carcinoma compared with those with blood group O.

IMPACT

ABO blood group can be a biomarker for pancreatic cancer risk among patients with IPMNs.

Systemic Immune-Inflammation Index and Changes of Neutrophil-Lymphocyte Ratio as Prognostic Biomarkers for Patients With Pancreatic Cancer Treated With Immune Checkpoint Blockade

The efficacy of current treatment regimens for pancreatic cancer (PC) remains unsatisfactory. In recent years, immune checkpoint blockade (ICB) therapy has shown promising anti-tumor outcomes in many malignancies, including PC. Inexpensive and readily available biomarkers which predict therapeutic responses and prognosis are in critical need. Systemic immune-inflammation index (SII) and neutrophil-lymphocyte ratio (NLR) are emerging predictors for prognosis of various tumors. We aim to investigate the prognostic significance of baseline SII, NLR, and their changes in PC patients treated with ICB. Our retrospective analysis included PC patients treated with ICB therapy in the Chinese PLA General Hospital. All demographic, biological, and clinical data were extracted from medical records. Relative changes of SII after two doses of ICB were defined as ΔSII% and calculated as (SII_{after 2 doses}-SII_baseline)/SII_baseline, and so was the case for ΔNLR%. Overall survival (OS) and progression-free survival (PFS) were compared using Kaplan-Meier curves. The prognostic significance of baseline SII, NLR, and their changes was assessed in univariate and multivariate analyses using the Cox proportional hazard regression model. In total, 122 patients with PC treated with ICB were included in the present analysis. Elevated baseline SII (HR=3.28; 95% CI:1.98–5.27; P=0.03) and ΔNLR% (HR=2.21; 95% CI:1.03–4.74; P=0.04) were significantly correlated with an increased risk of death. For PC patients receiving ICB combined with chemotherapies or radiotherapies as the first-line treatment, increased baseline SII was a negative predictor for both OS (HR=8.06; 95% CI:1.71–37.86; P=0.01) and PFS (HR=2.84; 95%CI:1.37–10.38; P=0.04). Our study reveals the prognostic value of baseline SII and NLR changes in PC patients receiving ICB therapy. The clinical utility of these prognostic biomarkers needs to be further studied in prospective studies.

Chelidonine Induces Apoptosis via GADD45a-p53 Regulation in Human Pancreatic Cancer Cells

Chelidonium majus has been used as a traditional medicine in China and western countries for various diseases, including inflammation and cancer. However, the anti-cancer effect of chelidonine, a major compound of C. majus extracts, on pancreatic cancer remains poorly understood. In this study, we found that treatment with chelidonine inhibited proliferation of BxPC-3 and MIA PaCa-2 human pancreatic cancer cells. Annexin-V/propidium iodide staining assay showed that this growth inhibitory effect of chelidonine was induced through apoptosis. We found that chelidonine treatment upregulated mRNA levels and transcription factor activity in both cell lines. Increases in protein expression levels of p53, GADD45A, p21 and cleaved caspase-3 were also observed, with more distinct changes in MIA PaCa-2 cells compared to the BxPC-3 cells. These results suggest that chelidonine induces pancreatic cancer apoptosis through the p53 and GADD45A pathways. Our findings provide new insights into the use of chelidonine for the treatment of pancreatic cancer.

The Bromodomain Inhibitor, INCB057643, Targets Both Cancer Cells and the Tumor Microenvironment in Two Preclinical Models of Pancreatic Cancer

Simple Summary

Pancreatic cancer remains a highly lethal disease, with only ~10% of patients still alive five years after diagnosis, as most patients already have advanced, metastatic disease at the time of diagnosis. Therefore, new treatments are needed for these patients. We tested INCB057643, a novel bromodomain inhibitor, in a relevant mouse model of pancreatic cancer, and this compound improves survival and reduces metastasis. Pancreatic cancers are very dense, as the stroma within the tumor can account for up to 90% of the tumor mass and is responsible for the failure of many drugs. INCB057643 modulates the immune cells within the tumor so they can attack and kill tumor cells. INCB057643 also alters immune cells within the pancreas in a mouse model of pancreatitis, which is inflammation of the pancreas that can promote the development of pancreatic cancer.

Abstract

In pancreatic cancer the tumor microenvironment (TME) can account for up to 90% of the tumor mass. The TME drives essential functions in disease progression, invasion and metastasis. Tumor cells can use epigenetic modulation to evade immune recognition and shape the TME toward an immunosuppressive phenotype. Bromodomain inhibitors are a class of drugs that target BET (bromodomain and extra-terminal) proteins, impairing their ability to bind to acetylated lysines and therefore interfering with transcriptional initiation and elongation. INCB057643 is a new generation, orally bioavailable BET inhibitor that was developed for treating patients with advanced malignancies. Kras^G12D/+; Trp53^R172H/+; Pdx-1-Cre (KPC) mice mimic human disease, with similar progression and incidence of metastasis. Treatment of established tumors in KPC mice with INCB057643 increased survival by an average of 55 days, compared to the control group. Moreover, INCB057643 reduced metastatic burden in these mice. KPC mice treated with INCB057643, starting at 4 weeks of age, showed beneficial changes in immune cell populations in the pancreas and liver. Similarly, INCB057643 modified immune cell populations in the pancreas of Kras^G12D/+; Pdx-1-Cre (KC) mice with pancreatitis, an inflammatory process known to promote pancreatic cancer progression. The data presented here suggest that the bromodomain inhibitor INCB057643 modulates the TME, reducing disease burden in two mouse models of pancreatic cancer. Furthermore, this work suggests that BRD4 may play a role in establishing the TME in the liver, a primary metastatic site for pancreatic cancer.

IGFBP2 promotes tumor progression by inducing alternative polarization of macrophages in pancreatic ductal adenocarcinoma through the STAT3 pathway

Tumor-associated macrophages (TAMs) represent the M2-like phenotype with potent immunosuppressive activity, and play a pro-tumor role in pancreatic ductal adenocarcinoma (PDAC) biology. In this study, we investigated the role of the insulin-like growth factor binding protein 2 (IGFBP2) as a determinant of TAM polarity. Clinical data revealed that the levels of IGFBP2 correlated with M2 TAMs accumulation and disease progression in human PDAC. In vivo mouse model experiments showed that IGFBP2 promoted an immunosuppressive microenvironment and tumor growth in a macrophage dependent manner. Bioinformatics analysis of PDAC transcriptomes revealed a significant association between IGFBP2 expression and M2 macrophage polarization and signal transducer and activator of transcription 3 (STAT3) activation. Mechanistic investigations demonstrated that IGFBP2 augmented the expression and secretion of IL-10 through STAT3 activation in PDAC cells, which induced TAM polarization toward an M2 phenotype. IGFBP2-polarized M2 macrophages significantly increased Tregs infiltration and impaired antitumor T-cell immunity in a mouse model. Thus, our investigations have illuminated the IGFBP2 signaling pathway that contributes to the macrophage-based immunosuppressive microenvironment in PDAC, suggesting that blocking the IGFBP2 axis constitutes a potential treatment strategy to reset TAM polarization toward an antitumor state in PDAC.

Nanoscale platform for delivery of active IRINOX to combat pancreatic cancer

Due to its late diagnosis and dismal prognosis, pancreatic ductal adenocarcinoma (PDAC) is one of the most devastating solid malignancies, with only 9% of patients surviving after being diagnosed. A multidrug chemotherapeutic regimen FOL-F-IRIN-OX (combination of 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin) offers survival benefits superior to that of gemcitabine single agent, but the treatment-related side effects are also severe. To overcome this therapeutic barrier, we developed polymeric micelles bearing active formats of irinotecan and oxaliplatin, SN38 and 1,2-diaminocyclohexane‑platinum (II), DACHPt. Crosslinked micelles were prepared using amphiphilic PEG-b-poly(L-glutamic acid)/SN38 conjugates and subsequently loaded with DACHPt. The dual drug-loaded micelles exhibited improved colloidal stability, prolonged drug release and remarkable cytotoxicity in human pancreatic cancer cell lines and Kras^G12D; Trp52^R172H/+; Pdx-1 Cre murine tumor organoids models. In vivo, (SN38 + DACHPt)-loaded micelles displayed superior antitumor and antimetastatic activities without impairing safety. Our results suggest that nanomedicine mimicking irinotecan and oxaliplatin as parts of FOLFIRINOX regimen may further improve the feasibility of this multidrug treatment for patients with advanced pancreatic cancer.

Marked Decrease in CA 19-9 Level Belies Rapidly Progressive Lymphangitic Carcinomatosis in a Case of Metastatic Pancreatic Cancer

Background: The CA 19-9 tumor marker is commonly used alongside imaging to trend chemotherapy response in patients with pancreatic ductal adenocarcinoma.

Presentation: We describe an unusual clinical case of metastatic pancreatic cancer who achieved a marked decline in CA 19-9 but paradoxically developed widespread pulmonary lymphangitic carcinomatosis leading to rapid clinical decline and death.

Conclusions: This case highlights the limitations of using the CA 19-9 tumor marker in isolation.

Immunomodulation in Pancreatic Cancer

Pancreatic cancer has a high mortality rate, and its incidence is increasing worldwide. The almost universal poor prognosis of pancreatic cancer is partly due to symptoms presenting only at late stages and limited effective treatments. Recently, immune checkpoint blockade inhibitors have drastically improved patient survival in metastatic and advanced settings in certain cancers. Unfortunately, these therapies are ineffective in pancreatic cancer. However, tumor biopsies from long-term survivors of pancreatic cancer are more likely to be infiltrated by cytotoxic T-cells and certain species of bacteria that activate T-cells. These observations suggest that T-cell activation is essential for anti-tumor immunity in pancreatic cancers. This review discusses the immunological mechanisms responsible for effective anti-tumor immunity and how immune-based strategies can be exploited to develop new pancreatic cancer treatments.

Gemcitabine-Based Neoadjuvant Treatment in Borderline Resectable Pancreatic Ductal Adenocarcinoma: A Meta-Analysis of Individual Patient Data

Background: Non-randomized studies have investigated multi-agent gemcitabine-based neo-adjuvant therapies (GEM-NAT) in borderline resectable pancreatic ductal adenocarcinoma (BR-PDAC). Treatment sequencing and specific elements of neoadjuvant treatment are still under investigation. The present meta-analysis aims to assess the effectiveness of GEM-NAT on overall survival (OS) in BR-PDAC.

Patients and Methods: A meta-analysis of individual participant data (IPD) on GEM-NAT for BR-PDAC were performed. The primary outcome was OS after treatment with GEM-based chemotherapy. In the Individual Patient Data analysis data were reappraised and confirmed as BR-PDAC on provided radiological data.

Results: Six studies investigating GEM-NAT were included in the IPD metanalysis. The IPD metanalysis was conducted on 271 patients who received GEM-NAT. Pooled median patient-level OS was 22.2 months (95%CI 19.1–25.2). R0 rates ranged between 81 and 95% (I² = 0%, p = 0.64), respectively. Median OS was 27.8 months (95%CI 23.9–31.6) in the patients who received NAT-GEM followed by resection compared to 15.4 months (95%CI 12.3–18.4) for NAT-GEM without resection and 13.0 months (95%CI 7.4–18.5) in the group of patients who received upfront surgery (p < 0.0001). R0 rates ranged between 81 and 95% (I² = 0%, p = 0.64), respectively. Overall survival in the R0 group was 29.3 months (95% CI 24.3–34.2) vs. 16.2 months (95% CI 7·9–24.5) in the R1 group (p = 0·001).

Conclusions: The present study is the first meta-analysis combining IPD from a number of international centers with BR-PDAC in a cohort that underwent multi-agent gemcitabine neoadjuvant therapy (GEM-NAT) before surgery. GEM-NAT followed by surgical resection improve survival and R0 resection in BR-PDAC. Also, GEM-NAT may result in a good palliative option in non-resected patients because of progressive disease after neoadjuvant treatment. Results from randomized controlled trials (RCTs) are awaited to validate these findings.

Mitochondrial Metabolism in PDAC: From Better Knowledge to New Targeting Strategies

Cancer cells reprogram their metabolism to meet bioenergetics and biosynthetic demands. The first observation of metabolic reprogramming in cancer cells was made a century ago (“Warburg effect” or aerobic glycolysis), leading to the classical view that cancer metabolism relies on a glycolytic phenotype. There is now accumulating evidence that most cancers also rely on mitochondria to satisfy their metabolic needs. Indeed, the current view of cancer metabolism places mitochondria as key actors in all facets of cancer progression. Importantly, mitochondrial metabolism has become a very promising target in cancer therapy, including for refractory cancers such as Pancreatic Ductal AdenoCarcinoma (PDAC). In particular, mitochondrial oxidative phosphorylation (OXPHOS) is an important target in cancer therapy. Other therapeutic strategies include the targeting of glutamine and fatty acids metabolism, as well as the inhibition of the TriCarboxylic Acid (TCA) cycle intermediates. A better knowledge of how pancreatic cancer cells regulate mitochondrial metabolism will allow the identification of metabolic vulnerabilities and thus novel and more efficient therapeutic options for the benefit of each patient.

Hypoxia: a barricade to conquer the pancreatic cancer

Pancreatic cancer (PC) remains one of the most extremely lethal malignancies worldwide due to late diagnosis and early metastasis, with a 1-year overall survival rate of approximately 20%. The hypoxic microenvironment, induced by intratumoral hypoxia, promotes tumor invasion and progression, leading to chemotherapy or radiotherapy resistance and eventual mortality after treatment of PC. However, the role of the hypoxic microenvironment in PC is complicated and requires further investigation. In this article, we review recent advances regarding the regulation of malignant behaviors in PC, which provide insight into the potential of hypoxic microenvironment activation therapy for the therapeutic agents.

DNA Damage-Inducing Anticancer Therapies: From Global to Precision Damage

DNA damage-inducing therapies are of tremendous value for cancer treatment and function by the direct or indirect formation of DNA lesions and subsequent inhibition of cellular proliferation. Of central importance in the cellular response to therapy-induced DNA damage is the DNA damage response (DDR), a protein network guiding both DNA damage repair and the induction of cancer-eradicating mechanisms such as apoptosis. A detailed understanding of DNA damage induction and the DDR has greatly improved our knowledge of the classical DNA damage-inducing therapies, radiotherapy and cytotoxic chemotherapy, and has paved the way for rational improvement of these treatments. Moreover, compounds targeting specific DDR proteins, selectively impairing DNA damage repair in cancer cells, form a promising novel therapy class that is now entering the clinic. In this review, we give an overview of the current state and ongoing developments, and discuss potential avenues for improvement for DNA damage-inducing therapies, with a central focus on the role of the DDR in therapy response, toxicity and resistance. Furthermore, we describe the relevance of using combination regimens containing DNA damage-inducing therapies and how they can be utilized to potentiate other anticancer strategies such as immunotherapy.

Impact of granulocyte colony-stimulating factor on FOLFIRINOX-induced neutropenia prevention: A population pharmacokinetic/pharmacodynamic approach

AIMS

Granulocyte colony-stimulating factor (G-CSF) is frequently prescribed to prevent chemotherapy-induced neutropenia, but the administration schedule remains empirical in case of bimonthly chemotherapy such as FOLFIRINOX regimen. This pharmacokinetic/pharmacodynamic (PK/PD) study was performed to determine the effect of different G-CSF regimens on the incidence and duration of neutropenia following FOLFIRINOX administration in order to propose an optimal G-CSF dosing schedule.

METHODS

A population PK/PD model was developed to describe individual neutrophil time course from absolute neutrophil counts (ANC) obtained in 40 advanced cancer patients receiving FOLFIRINOX regimen. The structural model considered ANC dynamics, neutropenic effect of cytotoxics and the stimulating effect of G-CSF on neutrophils. Final model estimates were used to simulate different G-CSF dosing schedules for 1000 virtual subjects. The incidence and duration of neutropenia were then calculated for different G-CSF dosing schedules.

RESULTS

The final model successfully described the myelosuppressive effect induced by the 3 cytotoxics for all patients. Simulations showed that pegfilgrastim administration reduced the risk of severe neutropenia by 22.9% for subjects with low ANC at the start of chemotherapy. Median duration in this group was also shortened by 3.1 days when compared to absence of G-CSF. Delayed G-CSF administration was responsible for higher incidence and longer duration of neutropenia compared to absence of administration.

CONCLUSION

The PK/PD model well described our population's ANC data. Simulations showed that pegylated-G-CSF administration 24 hours after the end of chemotherapy seems to be the optimal schedule to reduce FOLFIRINOX-induced neutropenia. We also underline the potential negative effect of G-CSF maladministration.

Increased Rate of Complete Pathologic Response After Neoadjuvant FOLFIRINOX for BRCA Mutation Carriers with Borderline Resectable Pancreatic Cancer

BACKGROUND

Neoadjuvant FOLFIRINOX is a standard-of-care treatment for BRPC patients. Patients with gBRCAm who have demonstrated improved response to platinum-based chemotherapy may have impaired homologous repair deficiency. This study aimed to describe the pathologic complete response rate and long-term survival for patients with germline BRCA1 or BRCA2 mutation (gBRCAm) and borderline resectable pancreatic cancer (BRPC) treated with neoadjuvant FOLFIRINOX.

METHODS

A dual-center retrospective analysis was performed. Patients who had BRPC treated with neoadjuvant FOLFIRINOX followed by curative resection were identified from clinical databases. Pathologic complete response was defined as no viable tumor cells present in the specimen. Common founder Jewish germline BRCA1 or BRCA2 mutation was determined for available patients.

RESULTS

The 61 BRPC patients in this study underwent resection after neoadjuvant FOLFIRINOX. Analysis of BRCA mutation was performed for 39 patients, and 9 patients were found to be BRCA2 germline mutation carriers. The pathologic complete response rate was 44.4% for the gBRCAm patients and 10% for the BRCA non-carriers (p = 0.009). The median disease-free survival was not reached for the gBRCAm patients and was 7 months for the BRCA non-carriers (p = 0.03). The median overall survival was not reached for the gBRCAm patients and was 32 months for the BRCA non-carriers (p = 0.2). After a mean follow-up period of 33.7 months, all eight patients with pathologic complete response were disease-free.

CONCLUSIONS

The study showed that gBRCAm patients with BRPC have an increased chance for pathologic complete response and prolonged survival after neoadjuvant FOLFIRINOX. The results support the benefit of exposing gBRCAm patients to platinum-based chemotherapy early in the course of the disease. Neoadjuvant FOLFIRINOX should be considered for BRCA carriers who have resectable pancreatic cancer.