Multidisciplinary standards of care and recent progress in pancreatic ductal adenocarcinoma

Nodal Enhances Perineural Invasion in Pancreatic Cancer by Promoting Tumor-Nerve Convergence

Perineural invasion (PNI) is a typical feature of pancreatic ductal adenocarcinoma (PDAC), which occurs in most cases. The embryonic protein Nodal plays a critical role in embryonic neural development and is overexpressed in human pancreatic cancer. In this study, we explored the contribution of Nodal to pancreatic cancer PNI and progression. We evaluated the function of Nodal in PNI by coculturing rat dorsal root ganglia and pancreatic cancer cells in vitro and performing cellular and molecular biology assays. The results illustrate that Nodal upregulates NGF (nerve growth factor), BDNF (brain-derived neurotrophic factor), and GDNF (glial cell line-derived neurotrophic factor) expression in pancreatic cancer cells and promotes cancer cell migration/invasion. Furthermore, in the in vitro 3D PNI model, Nodal enhances nerve outgrowth to pancreatic cancer cell colonies. Our study indicates that Nodal participates in tumor invasion by mediating neural and tumor cell signaling interactions, and inhibiting the expression of Nodal represents a potential strategy for targeting PNI in pancreatic cancer therapy.

Neoadjuvant Therapy Is Associated with Improved Chemotherapy Delivery and Overall Survival Compared to Upfront Resection in Pancreatic Cancer without Increasing Perioperative Complications

The role of neoadjuvant chemoradiotherapy and/or chemotherapy (neoCHT) in patients with pancreatic ductal adenocarcinoma (PDAC) is poorly defined. We hypothesized that patients who underwent neoadjuvant therapy (NAT) would have improved systemic therapy delivery, as well as comparable perioperative complications, compared to patients undergoing upfront resection. This is an IRB-approved retrospective study of potentially resectable PDAC patients treated within an academic quaternary referral center between 2011 and 2018. Data were abstracted from the electronic medical record using an institutional cancer registry and the National Surgical Quality Improvement Program. Three hundred and fourteen patients were eligible for analysis and eighty-one patients received NAT. The median overall survival (OS) was significantly improved in patients who received NAT (28.6 vs. 20.1 months, p = 0.014). Patients receiving neoCHT had an overall increased mean duration of systemic therapy (p < 0.001), and the median OS improved with each month of chemotherapy delivered (HR = 0.81 per month CHT, 95% CI (0.76-0.86), p < 0.001). NAT was not associated with increases in early severe post-operative complications (p = 0.47), late leaks (p = 0.23), or 30-90 day readmissions (p = 0.084). Our results show improved OS in patients who received NAT, driven largely by improved chemotherapy delivery, without an apparent increase in early or late perioperative complications compared to patients undergoing upfront resection.

Long non‑coding RNA CTBP1‑AS2 upregulates USP22 to promote pancreatic carcinoma progression by sponging miR‑141‑3p

Long non-coding RNAs (lncRNAs) feature prominently in pancreatic carcinoma progression. The present study aimed to clarify the biological functions, clinical significance and underlying mechanism of lncRNA CTBP1 antisense RNA 2 (CTBP1-AS2) in pancreatic carcinoma. Reverse transcription-quantitative PCR was performed to assess the expression levels of CTBP1-AS2, microRNA (miR)-141-3p and ubiquitin-specific protease 22 (USP22) mRNA in pancreatic carcinoma tissues and cell lines. Western blotting was used to examine USP22 protein expression in pancreatic carcinoma cell lines. Loss-of-function experiments were used to analyze the regulatory effects of CTBP1-AS2 on proliferation, apoptosis, migration and invasion of pancreatic carcinoma cells. Dual-luciferase reporter assay was used to examine the binding relationship between CTBP1-AS2 and miR-141-3p, as well as between miR-141-3p and USP22. It was demonstrated that CTBP1-AS2 expression was markedly increased in pancreatic carcinoma tissues and cell lines. High CTBP1-AS2 expression was associated with advanced clinical stage and lymph node metastasis of patients. Functional experiments confirmed that knocking down CTBP1-AS2 significantly inhibited pancreatic carcinoma cell proliferation, migration and invasion, and promoted cell apoptosis. In terms of mechanism, it was found that CTBP1-AS2 adsorbed miR-141-3p as a molecular sponge to upregulate the expression level of USP22. In conclusion, lncRNA CTBP1-AS2 may be involved in pancreatic carcinoma progression by regulating miR-141-3p and USP22 expressions; in addition, CTBP1-AS2 may be a diagnostic biomarker and treatment target for pancreatic carcinoma.

An Inflammatory Response Related Gene Signature Associated with Survival Outcome and Gemcitabine Response in Patients with Pancreatic Ductal Adenocarcinoma

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive tumors with an extremely low 5-year survival rate. Accumulating evidence has unveiled that inflammatory response promotes tumor progression, enhances angiogenesis, and causes local immunosuppression. Herein, we aim to develop an inflammatory related prognostic signature, and found it could be used to predict gemcitabine response in PDAC.

Methods: PDAC cohorts with mRNA expression profiles and clinical information were systematically collected from the four public databases. An inflammatory response related genes (IRRGs) prognostic signature was constructed by LASSO regression analysis. Kaplan–Meier survival analysis, receiver operating characteristic analysis, principal component analysis, and univariate and multivariate Cox analyses were carried out to evaluate effectiveness, and reliability of the signature. The correlation between gemcitabine response and risk score was evaluated in the TCGA-PAAD cohort. The GDSC database, pRRophetic algorithm, and connectivity map analysis were used to predict gemcitabine sensitivity and identify potential drugs for the treatment of PDAC. Finally, we analyzed differences in frequencies of gene mutations, infiltration of immune cells, as well as biological functions between different subgroups divided by the prognostic signature.

Results: We established a seven IRRGs (ADM, DCBLD2, EREG, ITGA5, MIF, TREM1, and BTG2) signature which divided the PDAC patients into low- and high-risk groups. Prognostic value of the signature was validated in 11 PDAC cohorts consisting of 1337 PDAC patients from 6 countries. A nomogram that integrated the IRRGs signature and clinicopathologic factors of PDAC patients was constructed. The risk score showed positive correlation with gemcitabine resistance. Two drugs (BMS-536924 and dasatinib) might have potential therapeutic implications in high-risk PDAC patients. We found that the high-risk group had higher frequencies of KRAS, TP53, and CDKN2A mutations, increased infiltration of macrophages M0, neutrophils, and macrophages M2 cells, as well as upregulated hypoxia and glycolysis pathways, while the low-risk group had increased infiltration of CD8⁺ T, naïve B, and plasma and macrophages M1 cells.

Conclusion: We constructed and validated an IRRGs signature that could be used to predict the prognosis and gemcitabine response of patients with PDAC, as well as two drugs (BMS-536924 and dasatinib) may contribute to PDAC treatment.

Caring experiences of family caregivers of patients with pancreatic cancer: an integrative literature review

PURPOSE

This review summarizes and synthesizes the available empirical literature on the experiences concerned with the problems and challenges faced by caregivers of patients with pancreatic cancer.

METHODS

An integrative review method was used, and a literature search was conducted using five databases. We searched the terms "pancreatic cancer," "caregiver," and "experience," and used the Boolean operators OR and AND to combine them. The Joanna Briggs Institute critical appraisal tools were used to assess the quality of the included studies.

RESULTS

Four qualitative studies, one mixed method, and three quantitative studies met the selection criteria and were included in the review. Informal family caregivers of patients with pancreatic cancer experienced multifaceted roles, lack of information, difficulties in maintaining emotional well-being, and positive coping. The factors associated with their caring experience included the caregivers' demographics, patients' psychological status, and clinical characteristics.

CONCLUSION

Caregivers of patients with pancreatic cancer have various experiences while providing care. Health care providers should offer opportunities for caregivers to recognize their feelings, provide sufficient information and psychological support, and foster coping strategies to maintain the physical and psychosocial well-being of caregivers.

Overcoming Gemcitabine Resistance in Pancreatic Cancer Using the BCL-XL-Specific Degrader DT2216

Pancreatic cancer is the third most common cause of cancer-related deaths in the United States. Although gemcitabine is the standard of care for most patients with pancreatic cancer, its efficacy is limited by the development of resistance. This resistance may be attributable to the evasion of apoptosis caused by the overexpression of BCL-2 family antiapoptotic proteins. In this study, we investigated the role of BCL-XL in gemcitabine resistance to identify a combination therapy to more effectively treat pancreatic cancer. We used CRISPR-Cas9 screening to identify the key genes involved in gemcitabine resistance in pancreatic cancer. Pancreatic cancer cell dependencies on different BCL-2 family proteins and the efficacy of the combination of gemcitabine and DT2216 (a BCL-XL proteolysis targeting chimera or PROTAC) were determined by MTS, Annexin-V/PI, colony formation, and 3D tumor spheroid assays. The therapeutic efficacy of the combination was investigated in several patient-derived xenograft (PDX) mouse models of pancreatic cancer. We identified BCL-XL as a key mediator of gemcitabine resistance. The combination of gemcitabine and DT2216 synergistically induced cell death in multiple pancreatic cancer cell lines in vitro In vivo, the combination significantly inhibited tumor growth and prolonged the survival of tumor-bearing mice compared with the individual agents in pancreatic cancer PDX models. Their synergistic antitumor activity is attributable to DT2216-induced degradation of BCL-XL and concomitant suppression of MCL-1 by gemcitabine. Our results suggest that DT2216-mediated BCL-XL degradation augments the antitumor activity of gemcitabine and their combination could be more effective for pancreatic cancer treatment.

Surgical Management of Non-Metastatic Pancreatic Cancer in the United Kingdom: Results of a Nationwide Survey on Current Practice

BACKGROUND

It is presently unclear what clinical pathways are followed for patients with non-metastatic PDAC in specialised centres for pancreatic surgery across the United Kingdom (UK).

METHODS

Between August 2019 and August 2020 an electronic survey was conducted aiming at a national cohort of pancreatic surgeons in the UK. Participants replied to a list of standardised questions and clinical vignettes, and data were collected and analysed focusing on management preferences, resectability criteria, and contraindications to surgery.

RESULTS

Within the study period, 65 pancreatic surgeons from 27 specialist centres in the UK (96%) completed the survey. Multidisciplinary team meetings are utilised universally for the management of patients with PDAC, however, different staging systems for resectability classification are being applied. In borderline resectable PDAC, most surgeons were keen to proceed with surgical exploration post NAT, but differences were noted in preferred chemotherapy regimens. Surgeons from standard volume institutions performed fewer vein resections annually and were more likely to deem patients with locally advanced PDAC as unresectable. Intra-institutional variability in patient management was also present and ranging between 20-80%.

CONCLUSIONS

Significant variability in the surgical management of non-metastatic PDAC was identified both on inter- and intra-institutional level.

Dysregulated splicing factor SF3B1 unveils a dual therapeutic vulnerability to target pancreatic cancer cells and cancer stem cells with an anti-splicing drug

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal cancer, requiring novel treatments to target both cancer cells and cancer stem cells (CSCs). Altered splicing is emerging as both a novel cancer hallmark and an attractive therapeutic target. The core splicing factor SF3B1 is heavily altered in cancer and can be inhibited by Pladienolide-B, but its actionability in PDAC is unknown. We explored the presence and role of SF3B1 in PDAC and interrogated its potential as an actionable target.

METHODS

SF3B1 was analyzed in PDAC tissues, an RNA-seq dataset, and publicly available databases, examining associations with splicing alterations and key features/genes. Functional assays in PDAC cell lines and PDX-derived CSCs served to test Pladienolide-B treatment effects in vitro, and in vivo in zebrafish and mice.

RESULTS

SF3B1 was overexpressed in human PDAC and associated with tumor grade and lymph-node involvement. SF3B1 levels closely associated with distinct splicing event profiles and expression of key PDAC players (KRAS, TP53). In PDAC cells, Pladienolide-B increased apoptosis and decreased multiple tumor-related features, including cell proliferation, migration, and colony/sphere formation, altering AKT and JNK signaling, and favoring proapoptotic splicing variants (BCL-XS/BCL-XL, KRASa/KRAS, Δ133TP53/TP53). Importantly, Pladienolide-B similarly impaired CSCs, reducing their stemness capacity and increasing their sensitivity to chemotherapy. Pladienolide-B also reduced PDAC/CSCs xenograft tumor growth in vivo in zebrafish and in mice.

CONCLUSION

SF3B1 overexpression represents a therapeutic vulnerability in PDAC, as altered splicing can be targeted with Pladienolide-B both in cancer cells and CSCs, paving the way for novel therapies for this lethal cancer.

Characterization of the GATA Transcription Factor Family and Exploration of Their Relevance to Immune Infiltration and Tumor Microenvironment in Pancreatic Cancer

BACKGROUND

Pancreatic cancer (PC) presents a phenomenal disease burden worldwide. The GATA transcription factor family is associated with a variety of human malignancies. However, the relation between GATA family members (GATAs) and PC has not been elucidated.

METHODS

This study integrates large-scale bioinformatics database resources to analyze the expression patterns of GATAs in PC patients and explore their underlying function mechanism and relevance to immune infiltration and other different cell types in the tumor microenvironment in pancreatic cancer. First, the expression pattern of GATAs in pancreatic cancer was detected by the Oncomine database and the Gene Expression Profile Interaction Analysis (GEPIA2) database and verified through other datasets in the R2 platform. Then, we used the cBioPortal database and the Human Protein Atlas to assess the correlation between GATAs and clinicopathological features of PC. Then, survival analyses were performed to identify candidate prognostic factors in the GATA family in PC patients. Further, we performed gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, protein-protein interaction (PPI) network, immune-infiltration correlation analysis, and cell type analysis of the tumor microenvironment at the single-cell level to explain the function of GATAs in pancreatic cancer.

RESULTS

We found that GATA3 and GATA6 were highly expressed in pancreatic cancer, and the expression levels of GATA4 and GATA6 correlated with the pathological stage, differentiation grade, and molecular subtype of pancreatic cancer. The survival analysis revealed that lower GATA4 of PC patients was associated with better outcomes, and higher GATA6 might be associated with longer OS. In addition, GATA3 was associated with immune cell infiltration of PC, and GATA6 was mainly distributed in the epithelial cells with ductal phenotype.

CONCLUSION

This work tentatively identified GATA3, GATA4, and GATA6 in the GATA family associated with pancreatic cancer. GATA4 may serve as a prognostic factor for PC patients, and GATA6 may act as a subtype marker for PC. In addition, GATA3 may reflect the immune-infiltration status of PC.

Can local ablative techniques replace surgery for locally advanced pancreatic cancer?

In the treatment of pancreatic ductal adenocarcinoma (PDAC) the best chance at long term survival or cure has to date always included the complete surgical removal of the tumor. However, locally advanced pancreatic cancer (LAPC), about 25% of all newly diagnosed PDAC, is defined by its primary technical unresectability due to infiltration of visceral arteries and absence of metastasis. Induction therapies, especially FOLFIRINOX treatment, together with technical surgical advancement have increased the numbers for conversion to secondary resectability. Recent data on resections after induction therapy show promising, almost doubled survival compared to palliative treatment. Yet, around 70% of LAPC remain unresectable after induction therapy, often due to persistent local invasion. As locally ablative techniques are becoming more widely available this review examines their possible applicability to substitute for surgery in these cases which we propose to group under the new term "Inconvertible LAPC". The need for defining this novel subgroup who might benefit from ablative treatment is based on the findings in our review that high-level evidence on ablative techniques for PDAC is largely lacking and the latest effective, harmonized treatment guidelines for LAPC are not often incorporated in these studies. The "inconvertible LAPC" label requires persistent unresectability after staging and induction therapy of LAPC according to current guidelines followed by liberal indication for aggressive surgical exploration at a center equipped for extended pancreatic resections. Ideally, this specification of a new, distinct patient group will also put it in the spotlight more, hopefully prompt more trials designed to generate robust evidence and optimize transferability of study results.

Undertreatment of Pancreatic Cancer: The Intersection of Bias, Biology, and Geography

Pancreatic cancer is the third leading cause of cancer deaths in the United States. Black patients with pancreatic cancer experience higher incidence and increased mortality. Although racial biologic differences exist, socioeconomic status, insurance type, physician bias, and patient beliefs contribute to the disparities in outcomes observed among patients who are Black, indigenous, and people of color.

Long Noncoding Competing Endogenous RNA Networks in Pancreatic Cancer

Pancreatic cancer (PC) is a highly malignant disease characterized by insidious onset, rapid progress, and poor therapeutic effects. The molecular mechanisms associated with PC initiation and progression are largely insufficient, hampering the exploitation of novel diagnostic biomarkers and development of efficient therapeutic strategies. Emerging evidence recently reveals that noncoding RNAs (ncRNAs), including long ncRNAs (lncRNAs) and microRNAs (miRNAs), extensively participate in PC pathogenesis. Specifically, lncRNAs can function as competing endogenous RNAs (ceRNAs), competitively sequestering miRNAs, therefore modulating the expression levels of their downstream target genes. Such complex lncRNA/miRNA/mRNA networks, namely, ceRNA networks, play crucial roles in the biological processes of PC by regulating cell growth and survival, epithelial-mesenchymal transition and metastasis, cancer stem cell maintenance, metabolism, autophagy, chemoresistance, and angiogenesis. In this review, the emerging knowledge on the lncRNA-associated ceRNA networks involved in PC initiation and progression will be summarized, and the potentials of the competitive crosstalk as diagnostic, prognostic, and therapeutic targets will be comprehensively discussed.

Comprehensive Analysis of E3 Ubiquitin Ligases Reveals Ring Finger Protein 223 as a Novel Oncogene Activated by KLF4 in Pancreatic Cancer

Pancreatic cancer is one of the major malignancies and causes of mortality worldwide. E3 ubiquitin-protein ligases transfer activated ubiquitin from ubiquitin-conjugating enzymes to protein substrates and confer substrate specificity in cancer. In this study, we first downloaded data from The Cancer Genome Atlas pancreatic adenocarcinoma dataset, acquired all 27 differentially expressed genes (DEGs), and identified genomic alterations. Then, the prognostic significance of DEGs was analyzed, and eight DEGs (MECOM, CBLC, MARCHF4, RNF166, TRIM46, LONRF3, RNF39, and RNF223) and two clinical parameters (pathological N stage and T stage) exhibited prognostic significance. RNF223 showed independent significance as an unfavorable prognostic marker and was chosen for subsequent analysis. Next, the function of RNF223 in the pancreatic cancer cell lines ASPC-1 and PANC-1 was investigated, and RNF223 silencing promoted pancreatic cancer growth and migration. To explore the potential targets and pathways of RNF223 in pancreatic cancer, quantitative proteomics was applied to analyze differentially expressed proteins, and metabolism-related pathways were primarily enriched. Finally, the reason for the elevated expression of RNF223 was analyzed, and KLF4 was shown to contribute to the increased expression of RNF233. In conclusion, this study comprehensively analyzed the clinical significance of E3 ligases. Functional assays revealed that RNF223 promotes cancer by regulating cell metabolism. Finally, the elevated expression of RNF223 was attributed to KLF4-mediated transcriptional activation. This study broadens our knowledge regarding E3 ubiquitin ligases and signal transduction and provides novel markers and therapeutic targets in pancreatic cancer.

CYP2J2produced epoxyeicosatrienoic acids contribute to the ferroptosis resistance of pancreatic ductal adenocarcinoma in a PPARdependent manner

OBJECTIVES

Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant digestive tract tumors with a poor prognosis and high recurrence rate. Recently, ferroptosis resistance has been found in PDAC. However, the underlying mechanism of ferroptosis resistance has not been fully elucidated. Cytochrome P450 2J2 (CYP2J2) is the main enzyme which mediates arachidonic acid to produce epoxyeicosatrienoic acids (EETs) in human tissues. It has been reported that EETs involve in the development of cancer, while the roles of EETs in PDAC and ferroptosis remain unclear.This study aims to explore the effect of CYP2J2/EETs on ferroptosis of human pancreatic ductal adenocarcinoma cells PANC-1 cells and the underlying mechanisms.

METHODS

The tumor tissues and para-carcinoma tissues of 9 patients with PDAC were collected and the expression of CYP2J2 was detected with real-time PCR and Western blotting. Enzyme-linked immunosorbent assay (ELISA) was used to detect the level of 8,9-dihydroxyeicosatrienoic acid (8,9-DHET), and the degradation product of 8,9-epoxyeicosa-trienoic acid (8,9-EET). PANC-1 cells were used in this study. The ferroptosis inducer erastin was used to induce ferroptosis. The intracellular long-chain acyl-CoA synthetase 4 (ACSL4) protein level, lactate dehydrogenase (LDH) activity, malondialdehyde (MDA) content, Fe2+ concentration, and cell survival were detected. The 8,9-EET was pretreated to observe its effect on erastin-induced ferroptosis in PANC-1 cells. Lentivirus was used to construct a CYP2J2 knockdown cell line to observe its effect on the ferroptosis of PANC-1 cells induced by erastin. A peroxisome proliferation-activated receptor γ (PPARγ) blocker was used to observe the effect of 8,9-EET on erastin-induced glutathione peroxidase 4 (GPX4) and MDA content in PANC-1 cells.

RESULTS

High expression of CYP2J2 was found in PDAC, accompanied by an increased level of 8,9-DHET. The 8,9-EET pretreatment significantly attenuated the PANC-1 cell death induced by erastin. The 8,9-EET reduced the Fe2+ concentration, LDH activity and MDA content, and ACSL4 protein expression in erastin-treated PANC-1 cells. The 8,9-EET also restored the ferroportin (FPN) and ferroptosis suppressor protein 1 (FSP1) mRNA expressions in erastin-treated PANC-1 cells. But CYP2J2 knockdown exacerbated the erastin-induced ferroptosis in PANC-1 cells. Besides, CYP2J2 knockdown furtherly down-regulated the gene expression of FPN and FSP1. The 8,9-EET increased the expression of GPX4 in the erastin-treated PANC-1 cells, which was eliminated by a PPARγ blocker GW9662. And GW9662 abolished the anti-ferroptosis effects of 8,9-EET.

CONCLUSIONS

CYP2J2/EETs are highly expressed in PDAC tissues. EETs inhibit the ferroptosis via up-regulation of GPX4 in a PPARγ-dependent manner, which contributes to the ferroptosis resistance of PDAC.

Simple prognostic markers for optimal treatment of patients with unresectable pancreatic cancer

Most patients with pancreatic cancer are ineligible for curative resection at diagnosis, resulting in poor prognosis. This study aimed to evaluate the prognostic factors in patients with unresectable pancreatic cancer.We retrospectively collected clinical data from 196 patients with unresectable pancreatic cancer who received palliative chemotherapy (N = 153) or palliative care alone (N = 43) from January 2011 to December 2013. Patients' background data and overall survival were analyzed using the Cox proportional hazard regression model.In patients receiving palliative chemotherapy (gemcitabine-based regimen, 88.2%) and palliative care alone, the median (range) ages were 68 (43-91) and 78 (53-90) years, and metastatic diseases were present in 80% (N = 123) and 86% (N = 37), respectively. Multivariate analysis in the palliative chemotherapy patients showed that liver metastasis (hazard ratio [HR] 2.25, 95% confidence interval [CI] 1.58-3.20, P < .001), neutrophil-to-lymphocyte ratio (>4.5 vs ≤4.5; HR 3.45, 95% CI 2.22-5.36, P < .001), and cancer antigen 19-9 (CA19-9) (≥900 vs <900 U/mL; HR 1.45, 95% CI 1.02-2.05, P = .036) were independent prognostic factors. In those receiving palliative care alone, lung (HR 3.27, 95% Cl 1.46-7.35, p = 0.004) and peritoneum (HR 2.50, 95% CI 1.20-5.18, P = .014) metastases and the C-reactive protein-to-albumin ratio (≥1.3 vs <1.3; HR 3.33, 95% Cl 1.51-7.35, P = .003) were independent prognostic factors. Furthermore, patients with multiple factors had worse prognosis in both groups. Median survival time of palliative chemotherapy patients with risk factors 0, 1, 2, and 3 were 13.1 (95% CI 8.0-16.9), 9.4 (95% CI 7.9-10.1), 6.6 (95% CI 4.9-7.8), and 2.5 (95% CI 1.7-4.0) months, respectively. Similarly, median survival time was 5.7 (95% CI 1.3 -8.0), 2.1 (95% CI 1.5-3.9), and 1.3 (95% CI 0.6-1.7) months, respectively, for palliative care alone patients with risk factor 0, 1, and 2 to 3.Prognostic markers for pancreatic cancer were neutrophil-to-lymphocyte ratio, liver metastasis, and CA19-9 in patients undergoing palliative chemotherapy and C-reactive protein-to-albumin ratio and lung/peritoneum metastases in patients undergoing palliative care alone. These simple markers should be considered when explaining the prognosis and therapeutic options to patients.

N6 -methyladenosine-Mediated Upregulation of WTAPP1 Promotes WTAP Translation and Wnt Signaling to Facilitate Pancreatic Cancer Progression

Pseudogenes may play important roles in cancer. Here, we explore the mechanism and function of a pseudogene WTAPP1 in the progress of pancreatic ductal adenocarcinoma (PDAC). WTAPP1 RNA was significantly elevated in PDAC and was associated with poor prognosis in patients. Overexpression of WTAPP1 RNA promoted PDAC proliferation and invasiveness in vitro and in vivo. Mechanistically, N ⁶-methyladenosine (m⁶A) modification stabilized WTAPP1 RNA via CCHC-type zinc finger nucleic-acid binding protein (CNBP), resulting in increased levels of WTAPP1 RNA in PDAC cells. Excessive WTAPP1 RNA bound its protein-coding counterpart WT1-associated protein (WTAP) mRNA and recruited more EIF3 translation initiation complex to promote WTAP translation. Increased WTAP protein enhanced the activation of Wnt signaling and provoked the malignant phenotypes of PDAC. Decreasing WTAPP1 RNA significantly suppressed the in vivo growth and metastasis of PDAC cell lines and patient-derived xenografts. These results indicate that m⁶A-mediated increases in WTAPP1 expression promote PDAC progression and thus may serve as a therapeutic target. SIGNIFICANCE: This study reveals how aberrant m⁶A modification of the WTAPP1 pseudogene results in increased translation of its protein-coding counterpart to promote Wnt signaling, which contributes to pancreatic cancer progression.

Pancreatic Cancer Small Extracellular Vesicles (Exosomes): A Tale of Short- and Long-Distance Communication

Simple Summary

Even today, pancreatic cancer still has a dismal prognosis. It is characterized by a lack of early symptoms and thus late diagnosis as well as early metastasis. The majority of patients suffer from pancreatic ductal adenocarcinoma (PDAC). PDACs communicate extensively with cellular components of their microenvironment, but also with distant metastatic niches to facilitate tumor progression and dissemination. This crosstalk is substantially enabled by small extracellular vesicles (sEVs, exosomes) with a size of 30–150 nm that are released from the tumor cells. sEVs carry bioactive cargos that reprogram target cells to promote tumor growth, migration, metastasis, immune evasion, or chemotherapy resistance. Interestingly, sEVs also carry novel diagnostic, prognostic and potentially also predictive biomarkers. Moreover, engineered sEVs may be utilized as therapeutic agents, improving treatment options. The role of sEVs for PDAC development, progression, diagnosis, prognosis, and treatment is the focus of this review.

Abstract

Even with all recent advances in cancer therapy, pancreatic cancer still has a dismal 5-year survival rate of less than 7%. The most prevalent tumor subtype is pancreatic ductal adenocarcinoma (PDAC). PDACs display an extensive crosstalk with their tumor microenvironment (TME), e.g., pancreatic stellate cells, but also immune cells to regulate tumor growth, immune evasion, and metastasis. In addition to crosstalk in the local TME, PDACs were shown to induce the formation of pre-metastatic niches in different organs. Recent advances have attributed many of these interactions to intercellular communication by small extracellular vesicles (sEVs, exosomes). These nanovesicles are derived of endo-lysosomal structures (multivesicular bodies) with a size range of 30–150 nm. sEVs carry various bioactive cargos, such as proteins, lipids, DNA, mRNA, or miRNAs and act in an autocrine or paracrine fashion to educate recipient cells. In addition to tumor formation, progression, and metastasis, sEVs were described as potent biomarker platforms for diagnosis and prognosis of PDAC. Advances in sEV engineering have further indicated that sEVs might once be used as effective drug carriers. Thus, extensive sEV-based communication and applications as platform for biomarker analysis or vehicles for treatment suggest a major impact of sEVs in future PDAC research.

Features of primary pancreatic lymphoma: A bi-institutional review with an emphasis on typical and atypical imaging features

BACKGROUND

Primary pancreatic lymphoma (PPL) is a rare neoplasm. Being able to distinguish it from other pancreatic malignancies such as pancreatic ductal adenocarcinoma (PDAC) is important for appropriate management. Unlike PDAC, PPL is highly sensitive to chemotherapy and usually does not require surgery. Therefore, being able to identify PPL preoperatively will not only direct physicians towards the correct avenue of treatment, it will also avoid unnecessary surgical intervention.

AIM

To evaluate the typical and atypical multi-phasic computed tomography (CT) imaging features of PPL.

METHODS

A retrospective review was conducted of the clinical, radiological, and pathological records of all subjects with pathologically proven PPL who presented to our institutions between January 2000 and December 2020. Institutional review board approval was obtained for this investigation. The collected data were analyzed for subject demographics, clinical presentation, laboratory values, CT imaging features, and the treatment received. Presence of all CT imaging findings including size, site, morphology and imaging characteristics of PPL such as the presence or absence of nodal, vascular and ductal involvement in these subjects were recorded. Only those subjects who had a pre-treatment multiphasic CT of the abdomen were included in the study.

RESULTS

Twenty-nine cases of PPL were diagnosed between January 2000 and December 2020 (mean age 66 years; 13 males/16 females). All twenty-nine subjects were symptomatic but only 4 of the 29 subjects (14%) had B symptoms. Obstructive jaundice occurred in 24% of subjects. Elevated lactate dehydrogenase was seen in 81% of cases, whereas elevated cancer antigen 19-9 levels were present in only 10% of cases for which levels were recorded. The vast majority (90%) of tumors involved the pancreatic head and uncinate process. Mean tumor size was 7.8 cm (range, 4.0-13.8 cm). PPL presented homogenous hypoenhancement on CT in 72% of cases. Small volume peripancreatic lymphadenopathy was seen in 28% of subjects. Tumors demonstrated encasement of superior mesenteric vessels in 69% of cases but vascular stenosis or occlusion only manifested in 5 out of the twenty-nine individuals (17%). Mild pancreatic duct dilatation was also infrequent and seen in only 17% of cases, whereas common bile duct (CBD) dilation was seen in 41% of subjects. Necrosis occurred in 10% of cases. Size did not impact the prevalence of pancreatic and CBD dilation, necrosis, or mesenteric root infiltration (P = 0.525, P = 0.294, P = 0.543, and P = 0.097, respectively). Pancreatic atrophy was not present in any of the subjects.

CONCLUSION

PPL is an uncommon diagnosis best made preoperatively to avoid unnecessary surgery and ensure adequate treatment. In addition to the typical CT findings of PPL, such as homogeneous hypoenhancement, absence of vascular stenosis and occlusion despite encasement, and peripancreatic lymphadenopathy, this study highlighted many less typical findings, including small volume necrosis and pancreatic and bile duct dilation.

Pancreatic cancer in 2021: What you need to know to win

Pancreatic cancer is one of the solid tumors with the worst prognosis. Five-year survival rate is less than 10%. Surgical resection is the only potentially curative treatment, but the tumor is often diagnosed at an advanced stage of the disease and surgery could be performed in a very limited number of patients. Moreover, surgery is still associated with high post-operative morbidity, while other therapies still offer very disappointing results. This article reviews every aspect of pancreatic cancer, focusing on the elements that can improve prognosis. It was written with the aim of describing everything you need to know in 2021 in order to face this difficult challenge.

Biopsy bacterial signature can predict patient tissue malignancy

Considerable recent research has indicated the presence of bacteria in a variety of human tumours and matched normal tissue. Rather than focusing on further identification of bacteria within tumour samples, we reversed the hypothesis to query if establishing the bacterial profile of a tissue biopsy could reveal its histology / malignancy status. The aim of the present study was therefore to differentiate between malignant and non-malignant fresh breast biopsy specimens, collected specifically for this purpose, based on bacterial sequence data alone. Fresh tissue biopsies were obtained from breast cancer patients and subjected to 16S rRNA gene sequencing. Progressive microbiological and bioinformatic contamination control practices were imparted at all points of specimen handling and bioinformatic manipulation. Differences in breast tumour and matched normal tissues were probed using a variety of statistical and machine-learning-based strategies. Breast tumour and matched normal tissue microbiome profiles proved sufficiently different to indicate that a classification strategy using bacterial biomarkers could be effective. Leave-one-out cross-validation of the predictive model confirmed the ability to identify malignant breast tissue from its bacterial signature with 84.78% accuracy, with a corresponding area under the receiver operating characteristic curve of 0.888. This study provides proof-of-concept data, from fit-for-purpose study material, on the potential to use the bacterial signature of tissue biopsies to identify their malignancy status.

Prognostic Biomarkers and Immunotherapeutic Targets Among CXC Chemokines in Pancreatic Adenocarcinoma

Background

Pancreatic cancer is one of the principal causes of tumor-related death worldwide. CXC chemokines, a subfamily of functional chemotactic peptides, affect the initiation of tumor cells and clinical outcomes in several human malignant tumors. However, the specific biological functions and clinical significance of CXC chemokines in pancreatic cancer have not been clarified.

Methods

Bioinformatics analysis tools and databases, including ONCOMINE, GEPIA2, the Human Protein Atlas, DAVID, GeneMANIA, cBioPortal, STRING, DGidb, MethSurv, TRRUST, SurvExpress, SurvivalMeth, and TIMER, were utilized to clarify the clinical significance and biological functions of CXC chemokine in pancreatic cancer.

Results

Except for CXCL11/12, the transcriptional levels of other CXC chemokines in PAAD tissues were significantly elevated, and the expression level of CXCL16 was the highest among these CXC chemokines. Our findings also suggested that all of the CXC chemokines were linked to tumor-immune dysfunction involving the abundance of immune cell infiltration, and the Cox proportional hazard model confirmed that dendritic and CXCL3/5/7/8/11/17 were significantly associated with the clinical outcome of PAAD patients. Furthermore, increasing expressions of CXCL5/9/10/11/17 were related to unfavorable overall survival (OS), and only CXCL17 was a prognostic factor for disease-free survival (DFS) in PAAD patients. The expression pattern and prognostic power of CXC chemokines were further validated in the independent GSE62452 dataset. For the prognostic value of single CpG of DNA methylation of CXC chemokines in patients with PAAD, we identified 3 CpGs of CXCL1, 2 CpGs of CXCL2, 2 CpGs of CXCL3, 3 CpGs of CXCL4, 10 CpGs of CXCL5, 1 CpG of CXCL6, 1 CpG of CXCL7, 3 CpGs of CXCL12, 3 CpGs of CXCL14, and 5 CpGs of CXCL17 that were significantly associated with prognosis in PAAD patients. Moreover, the prognostic value of CXC chemokine signature in PAAD was explored and tested in two independent cohort, and results indicated that the patients in the low-risk group had a better OS compared with the high-risk group. Survival analysis of the DNA methylation of CXC chemokine signature demonstrated that PAAD patients in the high-risk group had longer survival times.

Conclusions

These findings reveal the novel insights into CXC chemokine expression and their biological functions in the pancreatic cancers, which might serve as accurate prognostic biomarkers and suitable immunotherapeutic targets for patients with pancreatic cancer.

Roles of the nervous system in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC), with its extremely poor prognosis, presents a substantial health problem worldwide. Outcomes have improved thanks to progress in surgical technique, chemotherapy, pre-/postoperative management, and centralization of patient care to high-volume centers. However, our goals are yet to be met. Recently, exome sequencing using PDAC surgical specimens has demonstrated that the most frequently altered genes were the axon guidance genes, indicating involvement of the nervous system in PDAC carcinogenesis. Moreover, perineural invasion has been widely identified as one poor prognostic factor. The combination of innovative technologies and extensive clinician experience with the nervous system come together here to create a new treatment option. However, evidence has emerged that suggests that the relationship between cancer and nerves in PDAC, the underlying mechanism, is not fully understood. In an attempt to tackle this lethal cancer, this review summarizes the anatomy and physiology of the pancreas and discusses the role of the nervous system in the pathophysiology of PDAC.

[Influence of molecular pathology on oncological surgery of pancreatic cancer]

Pancreatic cancer is a very aggressive malignant disease with an extremely poor prognosis; however, the survival of patients at all tumor stages is highly variable. Standard therapies, which are based predominantly on the TNM classification, patient's general condition and comorbidities, are highly variable in their effectiveness. In recent years, new technologies with multi-omics tumor characterizations have revealed the molecular heterogeneity of pancreatic cancer; however, in routine clinical practice, pancreatic cancer is usually considered as a uniform disease without paying attention to the individual tumor biology. Recent clinical studies have shown that molecular analyses can identify pharmacological targets and prognosis-relevant or treatment-relevant subtypes. Better methods for prognosis prediction and stratification based on clinical and molecular parameters could help to create more effective personalized multimodal therapy concepts and replace uniform standard therapies.

E3 ubiquitin ligase TRIM29 promotes pancreatic cancer growth and progression via stabilizing Yes-associated protein 1

BACKGROUND

Pancreatic cancer (PC) is one of the most fatal digestive system cancers. tripartite motif-29 (TRIM29) has been reported as oncogene in several human cancers. However, the precise role and underlying signal cascade of TRIM29 in PC progression remain unclear.

METHODS

Western blot, qRT-PCR and immunohistochemistry were used to analyze TRIM29 and Yes-associated protein 1 (YAP1) levels. CCK8 assays, EdU assays and flow cytometry were designed to explore the function and potential mechanism of TRIM29 and YAP1 in the proliferation of PC. Next, a nude mouse model of PC was established for validating the roles of TRIM29 and YAP1 in vivo. The relationship among TRIM29 and YAP1 was explored by co-immunoprecipitation and in vitro ubiquitination assay.

RESULTS

TRIM29 and YAP1 was significantly upregulated in PC patient samples, and TRIM29 expression was closely related to a malignant phenotype and poorer overall survival (OS) of PC patients. Functional assays revealed that TRIM29 knockdown suppresses cell growth, arrests cell cycle progression and promotes cell apoptosis of PC cells in vivo and in vitro. Furthermore, the rescue experiments demonstrated that TRIM29-induced proliferation is dependent on YAP1 in PC cells. Mechanistically, TRIM29 regulates YAP1 expression by directly binding to YAP1, and reduced its ubiquitination and degradation.

CONCLUSION

Taken together, these results identify a novel mechanism used by PC growth, and provide insight regarding the role of TRIM29 in PC.

The Impact of Neoadjuvant Treatment on Survival in Patients Undergoing Pancreatoduodenectomy with Concomitant Portomesenteric Venous Resection: An International Multicenter Analysis

OBJECTIVE

The aim of this study was to evaluate whether neoadjuvant therapy (NAT) critically influenced microscopically complete resection (R0) rates and long-term outcomes for patients with pancreatic ductal adenocarcinoma who underwent pancreatoduodenectomy (PD) with portomesenteric vein resection (PVR) from a diverse, world-wide group of high-volume centers.

SUMMARY BACKGROUND DATA

Limited size studies suggest that NAT improves R0 rates and overall survival compared to upfront surgery in resectable and borderline resectable pancreatic cancer (R/BR-PDAC) patients.

METHODS

This multicenter study analyzed consecutive patients with R/BR-PDAC who underwent PD with PVR in 23 high-volume centers from 2009 to 2018.

RESULTS

Data from 1192 patients with PD and PVR were collected and analyzed. The median age was 68 [interquartile range (IQR) 60-73] years and 52% were males. Some 186 (15.6%) and 131 (10.9%) patients received neoadjuvant chemotherapy (NAC) alone and neoadjuvant chemoradiotherapy (NACRT), respectively. The R0/R1/R2 rates were 57%, 39.3%, and 3.2% in patients who received NAT compared to 46.6%, 49.9%, and 3.5% in patients who did not, respectively (p=0.004). The 1-, 3-, and 5-year OS in patients receiving NAT was 79%, 41%, and 29%, while for those that did not it was 73%, 29%, and 18%, respectively (p<0.001). Multivariable analysis showed no administration of NAT, high tumor grade, lymphovascular invasion, R1/R2 resection, no adjuvant chemotherapy, occurrence of Clavien-Dindo grade 3 or higher postoperative complications within 90 days, preoperative diabetes mellitus, male sex and portal vein involvement were negative independent predictive factors for OS.

CONCLUSION

Patients with PDAC of the pancreatic head expected to undergo venous reconstruction should routinely be considered for NAT.

NEK2 inhibition triggers anti-pancreatic cancer immunity by targeting PD-L1

Despite the substantial impact of post-translational modifications on programmed cell death 1 ligand 1 (PD-L1), its importance in therapeutic resistance in pancreatic cancer remains poorly defined. Here, we demonstrate that never in mitosis gene A-related kinase 2 (NEK2) phosphorylates PD-L1 to maintain its stability, causing PD-L1-targeted pancreatic cancer immunotherapy to have poor efficacy. We identify NEK2 as a prognostic factor in immunologically "hot" pancreatic cancer, involved in the onset and development of pancreatic tumors in an immune-dependent manner. NEK2 deficiency results in the suppression of PD-L1 expression and enhancement of lymphocyte infiltration. A NEK binding motif (F/LXXS/T) is identified in the glycosylation-rich region of PD-L1. NEK2 interacts with PD-L1, phosphorylating the T194/T210 residues and preventing ubiquitin-proteasome pathway-mediated degradation of PD-L1 in ER lumen. NEK2 inhibition thereby sensitizes PD-L1 blockade, synergically enhancing the anti-pancreatic cancer immune response. Together, the present study proposes a promising strategy for improving the effectiveness of pancreatic cancer immunotherapy.

Cellular and molecular mechanisms of perineural invasion of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignant disease with a unique tumor microenvironment surrounded by an interlaced network of cancer and noncancerous cells. Recent works have revealed that the dynamic interaction between cancer cells and neuronal cells leads to perineural invasion (PNI), a clinical pathological feature of PDAC. The formation and function of PNI are dually regulated by molecular (e.g., involving neurotrophins, cytokines, chemokines, and neurotransmitters), metabolic (e.g., serine metabolism), and cellular mechanisms (e.g., involving Schwann cells, stromal cells, T cells, and macrophages). Such integrated mechanisms of PNI not only support tumor development, growth, invasion, and metastasis but also mediate the formation of pain, all of which are closely related to poor disease prognosis in PDAC. This review details the modulation, signaling pathways, detection, and clinical relevance of PNI and highlights the opportunities for further exploration that may benefit PDAC patients.

The pancreatic cancer genome revisited

Pancreatic cancer is a genetic disease, and the recurrent genetic alterations characteristic of pancreatic cancer indicate the cellular processes that are targeted for malignant transformation. In addition to somatic alterations in the most common driver genes (KRAS, CDKN2A, TP53 and SMAD4), large-scale studies have revealed major roles for genetic alterations of the SWI/SNF and COMPASS complexes, copy number alterations in GATA6 and MYC that partially define phenotypes of pancreatic cancer, and the role(s) of polyploidy and chromothripsis as factors contributing to pancreatic cancer biology and progression. Germline variants that increase the risk of pancreatic cancer continue to be discovered along with a greater appreciation of the features of pancreatic cancers with mismatch repair deficiencies and homologous recombination deficiencies that confer sensitivity to therapeutic targeting. Wild-type KRAS pancreatic cancers, some of which are driven by alternative oncogenic events affecting NRG1 or NTRK1 - for which targeted therapies exist - further underscore that pancreatic cancer is formally entering the era of precision medicine. Given the vast developments within this field, here we review the wide-ranging and most current information related to pancreatic cancer genomics with the goal of integrating this information into a unifying description of the life history of pancreatic cancer.

DeepPrognosis: Preoperative prediction of pancreatic cancer survival and surgical margin via comprehensive understanding of dynamic contrast-enhanced CT imaging and tumor-vascular contact parsing

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers and carries a dismal prognosis of ∼10% in five year survival rate. Surgery remains the best option of a potential cure for patients who are evaluated to be eligible for initial resection of PDAC. However, outcomes vary significantly even among the resected patients who were the same cancer stage and received similar treatments. Accurate quantitative preoperative prediction of primary resectable PDACs for personalized cancer treatment is thus highly desired. Nevertheless, there are a very few automated methods yet to fully exploit the contrast-enhanced computed tomography (CE-CT) imaging for PDAC prognosis assessment. CE-CT plays a critical role in PDAC staging and resectability evaluation. In this work, we propose a novel deep neural network model for the survival prediction of primary resectable PDAC patients, named as 3D Contrast-Enhanced Convolutional Long Short-Term Memory network (CE-ConvLSTM), which can derive the tumor attenuation signatures or patterns from patient CE-CT imaging studies. Tumor-vascular relationships, which might indicate the resection margin status, have also been proven to hold strong relationships with the overall survival of PDAC patients. To capture such relationships, we propose a self-learning approach for automated pancreas and peripancreatic anatomy segmentation without requiring any annotations on our PDAC datasets. We then employ a multi-task convolutional neural network (CNN) to accomplish both tasks of survival outcome and margin prediction where the network benefits from learning the resection margin related image features to improve the survival prediction. Our presented framework can improve overall survival prediction performances compared with existing state-of-the-art survival analysis approaches. The new staging biomarker integrating both the proposed risk signature and margin prediction has evidently added values to be combined with the current clinical staging system.

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.

Delta HU is a potential marker to predict chemotherapy response for unresectable pancreatic ductal adenocarcinoma

BACKGROUND

FOLFIRINOX and gemcitabine plus albumin-bound paclitaxel (AG) regimens are recommended as first-line therapy for both locally advanced and metastatic pancreatic cancer. However, there were no specific markers to conduct personalized regimen choice. The research is to assess delta Housfield unit (delta HU), which is the difference in CT attenuation value (in HU) between enhanced and nonenhanced phase of region of interest, as a marker for predicting chemotherapy response of unresectable pancreatic cancer.

METHODS

A total of 179 unresectable pancreatic cancer patients were enrolled in the study. Kaplan-Meier analysis and COX regression analysis were performed for progression-free survival (PFS) and overall survival. The differences of clinical characteristics were analyzed by χ 2test. Microvessel density (MVD) was calculated by immunochemistry staining of CD34.

RESULTS

Delta HU was an independent risk factor for unresectable pancreatic cancer (P = 0.017, HR 0.672, 95%CI 0.485-0.930). Patients with higher delta HU were associated with better PFS (P = 0.004). For modified FOLFIRINOX (mFOLFIRINOX) group, delta HU was an independent risk factor (P = 0.045, HR 0.571), but not for AG group (P = 0.473, HR 0.855). Delta HU was correlated with stroma MVD (P = 0.000, R = 0.483), not with parenchyma MVD (P = 0.074, R = 0.199).

CONCLUSIONS

Delta HU was a marker predicting chemotherapy response for unresectable pancreatic cancer. Higher delta HU was associated with better survival for patients receiving mFOLFIRINOX rather than AG. The delta HU was positively correlated with stroma MVD, explaining the relationship between delta HU and prognosis.

Clinical Effects of Stereotactic Body Radiation Therapy Targeting the Primary Tumor of Liver-Only Oligometastatic Pancreatic Cancer

Aim

To investigate the efficacy and safety of stereotactic body radiotherapy (SBRT) targeting the primary tumor for liver-only oligometastatic pancreatic cancer.

Methods

We compared the efficacy and safety of SBRT plus chemotherapy with chemotherapy alone in patients with liver-only oligometastatic pancreatic cancer. The populations were balanced by propensity score-weighted and propensity score-matched analyses based on baseline variables. The primary outcome was overall survival (OS). The secondary outcomes included progression free survival (PFS), local progression, metastatic progression and symptomatic local control.

Results

This is a retrospective study of 89 pancreatic cancer patients with liver-only oligometastasis. Overall, 34 (38.2%) and 55 (61.8%) patients received SBRT plus chemotherapy and chemotherapy alone, respectively. After propensity score matching, 1-year OS rate was 34.0% (95%CI, 17.8-65.1%) in the SBRT plus chemotherapy group and 16.5% (95%CI, 5.9-46.1%) in chemotherapy alone group (P=0.115). The 6-month PFS rate was 29.4% (95%CI, 15.4-56.1) in SBRT plus chemotherapy and 20.6% (95%CI, 8.8-48.6) in chemotherapy alone group (P=0.468), respectively. Further subgroup analysis indicated that the addition of SBRT improved OS in patients with primary tumor located in the head of pancreas (stratified HR, 0.28; 95% CI, 0.09 to 0.90) or good performance status (stratified HR, 0.24; 95% CI, 0.07 to 0.86). In terms of disease control, SBRT delayed local progression of pancreas (P=0.008), but not distant metastatic progression (P=0.56). Besides, SBRT offered significant abdominal/back pain relief (P=0.016) with acceptable toxicities.

Conclusions

The addition of SBRT to chemotherapy in patients with liver-only oligometastatic pancreatic cancer improves the OS of those with primary tumor located in the head of pancreas or good performance status. In addition, it is a safe and effective method for local progression control and local symptomatic palliation in patients with metastatic pancreatic cancer.

Single-cell analysis of pancreatic ductal adenocarcinoma identifies a novel fibroblast subtype associated with poor prognosis but better immunotherapy response

The current pathological and molecular classification of pancreatic ductal adenocarcinoma (PDAC) provides limited guidance for treatment options, especially for immunotherapy. Cancer-associated fibroblasts (CAFs) are major players of desmoplastic stroma in PDAC, modulating tumor progression and therapeutic response. Using single-cell RNA sequencing, we explored the intertumoral heterogeneity among PDAC patients with different degrees of desmoplasia. We found substantial intertumoral heterogeneity in CAFs, ductal cancer cells, and immune cells between the extremely dense and loose types of PDACs (dense-type, high desmoplasia; loose-type, low desmoplasia). Notably, no difference in CAF abundance was detected, but a novel subtype of CAFs with a highly activated metabolic state (meCAFs) was found in loose-type PDAC compared to dense-type PDAC. MeCAFs had highly active glycolysis, whereas the corresponding cancer cells used oxidative phosphorylation as a major metabolic mode rather than glycolysis. We found that the proportion and activity of immune cells were much higher in loose-type PDAC than in dense-type PDAC. Then, the clinical significance of the CAF subtypes was further validated in our PDAC cohort and a public database. PDAC patients with abundant meCAFs had a higher risk of metastasis and a poor prognosis but showed a dramatically better response to immunotherapy (64.71% objective response rate, one complete response). We characterized the intertumoral heterogeneity of cellular components, immune activity, and metabolic status between dense- and loose-type PDACs and identified meCAFs as a novel CAF subtype critical for PDAC progression and the susceptibility to immunotherapy.

Integrated analysis identifies S100A16 as a potential prognostic marker for pancreatic cancer

BACKGROUND

The new S100 protein family member S100A16 is functionally expressed in various cancers. This study explored the prognostic value and potential role of S100A16 in pancreatic cancer (PC).

METHODS

RNA-seq and clinical data were obtained from The Cancer Genome Atlas-Pancreatic Adenocarcinoma (TCGA-PAAD) dataset to compare the expression level of S100A16 between groups. The genes co-expressed with S100A16 in TCGA-PAAD were analyzed using cBioPortal. Gene Ontology and Kyoto Encyclopedia of Genes and genomes enrichment analyses were also performed on these genes. Pathways related to S100A16 expression dysregulation were explored using gene set enrichment analysis. The Tumor Immune Estimation Resource was used to analyze the correlation between S100A16 and infiltrating immune cells. The Kaplan-Meier method and Cox analyses were used to assess the prognostic significance of S100A16 for PC.

RESULTS

The S100A16 expression level was high in PC and increased with the degree of malignancy. The S100A16 functions in PC were mainly enriched in the immune modules, but negatively correlated with the immune activity (T-cell, cytokine, immune, co-receptor, signaling adaptor, cell adhesion molecule, chemokine, and JAK/STAT signaling) and infiltration level (T cells and macrophages). The strongest negative correlation was observed between the expression of CD8⁺ T cells and S100A16. Furthermore, high S100A16 expression also indicated worse overall survival and, therefore, worse prognosis of PC.

CONCLUSION

S100A16 is a potential independent prognostic marker and immunotherapy target for PC. Mechanistically, S100A16 potentially affects prognosis by extensive immunosuppression, including the inhibition of the anti-tumor immune response of CD8⁺ T cells.

LINC00460 promotes pancreatic cancer progression by sponging miR-491-5p

BACKGROUND

A growing body of studies have suggested that LINC00460 is instrumental in tumorigenesis and tumour progression. Nonetheless, the biological function and mechanisms of LINC00460 in pancreatic ductal adenocarcinoma (PDAC) remain vague.

METHODS

Analysis based on public databases and a quantitative reverse transcription-polymerase chain reaction were performed to screen for differentially expressed lncRNAs in PDAC and to detect LINC00460 expression in PDAC cell lines and clinical samples. The survival of patients in the up-regulated and down-regulated LINC00460 expression groups was compared by using the Kaplan-Meier method. In addition, the potential biological functions of LINC00460 in PDAC were explored by cell counting kit-8, colony formation, flow cytometry and transwell assays. Furthermore, bioinformatics analysis, luciferase reporter assays and rescue experiments were applied to demonstrate the mechanism by which LINC00460 could directly bind to and inhibit miR-491-5p.

RESULTS

LINC00460 is up-regulated in PDAC and correlates with adverse survival outcomes. The results of functional tests verified that LINC00460 knockdown inhibited both cell proliferation and cell migration. Additionally, knockdown led to G0/G1 cell cycle blockage and enhanced cell apoptosis. Mechanistic investigations revealed that LINC00460 directly binds to and attenuates the tumour suppressor miR-491-5p, thus accelerating PDAC progression.

CONCLUSIONS

This research showed that LINC00460 is overexpressed in PDAC and correlates with adverse clinical outcomes. Additionally, LINC00460 promotes the aggressiveness of PDAC by targeting miR-491-5p. Thus, LINC00460 may serve as diagnostic biomarker of PDAC and a new target for PDAC therapy.

European Cancer Organisation Essential Requirements for Quality Cancer Care (ERQCC): Pancreatic Cancer

European Cancer Organisation Essential Requirements for Quality Cancer Care (ERQCC) are written by experts representing all disciplines involved in cancer care in Europe. They give patients, health professionals, managers and policymakers a guide to essential care throughout the patient journey. Pancreatic cancer is an increasing cause of cancer mortality and has wide variation in treatment and care in Europe. It is a major healthcare burden and has complex diagnosis and treatment challenges. Care must be carried out only in pancreatic cancer units or centres that have a core multidisciplinary team (MDT) and an extended team of health professionals detailed here. Such units are far from universal in European countries. To meet European aspirations for comprehensive cancer control, healthcare organisations must consider the requirements in this paper, paying particular attention to multidisciplinarity and patient-centred pathways from diagnosis, to treatment, to survivorship.

Prognostic Utility of Prechemoradiotherapy Albumin-to-Alkaline Phosphatase Ratio in Unresectable Locally Advanced Pancreatic Carcinoma Patients

BACKGROUND

We investigated the prognostic usefulness of prechemoradiotherapy (CRT) albumin-to-alkaline phosphatase ratio (AAPR) in unresectable locally advanced pancreatic adenocarcinoma (LAPAC) patients managed with definitive concurrent CRT (CCRT).

METHODS

A sum of 136 LAPAC patients who consecutively underwent definitive CCRT was retrospectively analyzed. The AAPR (serum albumin (g/dL)/serum alkaline phosphatase (IU/L)) was calculated by using the parameters obtained from the routine biochemistry tests on the first day of the CCRT. Ideal AAPR cutoff was sought by utilizing receiver operating characteristic (ROC) curve analysis. The primary and secondary endpoints were the impact of the AAPR on the overall survival (OS) and progression-free survival (PFS) results, respectively.

RESULTS

At a median follow-up of 14.8 months (range: 3.2-85.7), the median PFS and OS times were 7.5 (95% confidence interval (CI): 6.0-9.0) and 14.9 months (95% CI: 11.9-17.9), respectively. The ideal common AAPR cutoff was identified at the rounded 0.46 (area under the curve: 72.3%; sensitivity: 71.2%; specificity: 70.3%) point that dichotomized the patients into two groups: low AAPR (L-AAPR; N = 71) and high AAPR (H-AAPR; N = 65) groups, respectively. Comparative survival analyses showed that the L-AAPR cohort had significantly shorter median PFS (6.8 (95% CI: 5.7-7.9) versus 11.3 (95% CI: 9.9-12.7) months; P = 0.005) and OS (12.8 (95% CI: 10.6-15.0) versus 19.2 (95% CI: 16.9-21.5) months; P = 0.001) durations than their H-AAPR counterparts, separately. Albeit the N1-2 (P = 0.004) and CA 19-9 > 90 U/mL (P = 0.008) were also found to be associated with inferior outcomes, yet the results of the multivariate analyses ascertained the L-AAPR as an independent indicator of diminished PFS (P = 0.003) and OS (P = 0.002) results.

CONCLUSION

The present results proposed that the pretreatment AAPR < 0.46 was a novel independent indicator of adverse PFS and OS in unresectable LAPAC patients undergoing definitive CCRT.

Combination of preoperative fibrinogen and D-dimer as a prognostic indicator in pancreatic ductal adenocarcinoma patients undergoing R0 resection

BACKGROUND

Patients with malignant tumors frequently exhibit hyperactivation of the coagulation system and secondary increased fibrinolytic activity. Fibrinogen and D-dimer are common indicators that are crucial in the coagulation/fibrinolysis system. Both indicators have been verified to have predictive value in the overall survival (OS) of many patients with solid malignancies.

AIM

To explore the prognostic significance of fibrinogen combined with D-dimer in pancreatic ductal adenocarcinoma (PDAC) patients undergoing radical R0 resection.

METHODS

We retrospectively analyzed the clinical data of 282 patients with PDAC undergoing radical R0 resection in the Cancer Hospital, Chinese Academy of Medical Sciences, between January 2010 and December 2019. The surv_cutpoint function of R language was used to determine the optimal cutoff values of the preoperative fibrinogen concentration and preoperative D-dimer concentration. Enrolled patients were further divided into the any-high group (high preoperative fibrinogen concentration and/or high preoperative D-dimer concentration) and the low-low group (low preoperative fibrinogen and D-dimer concentrations) according to the optimal cutoff values.

RESULTS

The optimal cutoff values of the preoperative fibrinogen concentration and preoperative D-dimer concentration were 3.31 g/L and 0.53 mg/L, respectively. Furthermore, multivariate Cox regression analysis showed that the preoperative fibrinogen concentration (HR: 1.603, 95%CI: 1.201-2.140, P = 0.001) and preoperative D-dimer concentration (HR: 1.355, 95%CI: 1.019-1.801, P = 0.036) exhibited obvious correlations with the OS of PDAC patients undergoing radical R0 resection. A prognostic analysis was further performed based on the subgroup results by using fibrinogen combined with D-dimer. The median OS duration of the low-low group (31.17 mo) was significantly longer than that of the any-high group (15.43 mo). Additionally, multivariate Cox regression analysis revealed that the degree of differentiation (P < 0.001), lymph node metastasis (HR: 0.663, 95%CI: 0.497-0.883, P = 0.005), preoperative CA19-9 level (HR: 1.699, 95%CI: 1.258-2.293, P = 0.001), adjuvant therapy (HR: 1.582, 95%CI: 1.202-2.081, P = 0.001) and preoperative combined grouping (HR: 2.397, 95%CI: 1.723-3.335, P < 0.001) were independent predictors of OS in PDAC patients undergoing radical R0 resection.

CONCLUSION

Preoperative fibrinogen combined with D-dimer plays a predictive role in OS, and low preoperative fibrinogen and D-dimer concentrations can indicate prolonged OS in PDAC patients undergoing radical R0 resection.

Identification of novel hub genes and lncRNAs related to the prognosis and progression of pancreatic cancer by microarray and integrated bioinformatics analysis

BACKGROUND

Pancreatic cancer (PC) is one of the most invasive and metastatic neoplasms among the fatal malignancies of the digestive system. Abnormal expression of genes and long non-coding RNAs (lncRNAs) are reportedly linked to multiple cancers. However, the lncRNA-mRNA expression profiles and their molecular mechanisms in PC progression are poorly known. This study aimed to map the hub genes and lncRNAs which might play core roles in the development of PC.

METHODS

This study used microarray expression analysis to screen for both differentially expressed genes (DEGs) and differentially expressed lncRNAs (DElncRNAs) between PC and matched adjacent non-tumor (AN) tissues. In order to clarify the functional classification of DEGs, we conducted GO and KEGG pathway enrichment analyses via the Enrichr database. LncRNA-mRNA co-expressed networks were also constructed to explore the probable core regulating DEGs and DElncRNAs. Subsequently, the hub genes and lncRNAs were validated via the ONCOMINE and GEPIA databases and the co-expressed networks.

RESULTS

By analyzing an mRNA-lncRNA microarray, we identified 943 mRNAs and 1,138 lncRNAs differentially expressed in PC tumors compared with the matched AN tissues. GO analysis confirmed that both up-regulated and down-regulated DEGs were enriched in multiple terms. The KEGG pathways enrichment analyses revealed that DEGs were mostly enriched in the focal adhesion and glutathione metabolism pathways, amongst others. Co-expressed networks were established to reveal the differential interactions between DEGs and DElncRNAs, and to indicate the core regulatory factors located at the core nodes of the co-expressed networks. The expression levels of potential core-regulating DEGs were validated by the GEPIA and ONCOMINE databases, and the relationship between overall survival and tumor stage and the potential core-regulating DEGs was analyzed using the GEPIA database. As a result, five genes and sixteen lncRNAs were finally considered as the hub transcripts in PC.

CONCLUSIONS

This study identified DEGs and DElncRNAs between PC tumors and matched AN tissues, and these transcripts were connected with malignant phenotypes in PC through different BPs and signaling pathways. Furthermore, five hub genes and sixteen lncRNAs were identified, which are expected to represent candidate diagnostic biomarkers or potential therapeutic targets for PC.

Expression of Genomic Instability-Related Molecules: Cyclin F, RRM2 and SPDL1 and Their Prognostic Significance in Pancreatic Adenocarcinoma

In the present study, we aimed to assess the selected components of cell cycle machinery, checkpoint, DNA repair, and synthesis, namely RRM2, cyclin F, and SPDL1 in pancreatic adenocarcinomas (PAC) by in-house immunohistochemistry (IHC) and bioinformatic analysis of public datasets, in terms of expression, correlation with clinicopathological parameters, and patient survival. Sixty eight patients with pancreatic ductal adenocarcinoma (PDAC) were included in our cohort study, and IHC was performed on tissue macroarrays. RNA-Seq-based transcriptome data for 177 PACs were retrieved from the Cancer Genome Atlas (TCGA). We found cyclin F, RRM2, and SPDL1 to be overexpressed at both protein and mRNA levels in tumor tissues compared to respective controls. Based on TCGA dataset, we have demonstrated that CCNF, RRM2, and SPDL1 are potent independent prognostic markers for poor overall survival, both by themselves and even more in combination with each other. Furthermore, high CCNF mRNA expression was associated with features of cancer progression. By contrast, overexpression of cyclin F or SPDL1 proteins denoted a good prognosis in PDAC patients; however, in the case of the former protein, the results did not reach statistical significance. Specifically, high levels of SPDL1 protein emerged as the most powerful independent prognostic factor associated with a better outcome. If validated, the CCNF/RRM2/SPDL1 three-gene panel developed in this study, as well as SPDL1 protein, may provide significant clinical implications for the prognosis prediction of PAC patients.

An Emerging Role for the Unfolded Protein Response in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer and one of the leading causes of cancer-associated deaths in the world. It is characterised by dismal response rates to conventional therapies. A major challenge in treatment strategies for PDAC is the presence of a dense stroma that surrounds the tumour cells, shielding them from treatment. This unique tumour microenvironment is fuelled by paracrine signalling between pancreatic cancer cells and supporting stromal cell types including the pancreatic stellate cells (PSC). While our molecular understanding of PDAC is improving, there remains a vital need to develop effective, targeted treatments. The unfolded protein response (UPR) is an elaborate signalling network that governs the cellular response to perturbed protein homeostasis in the endoplasmic reticulum (ER) lumen. There is growing evidence that the UPR is constitutively active in PDAC and may contribute to the disease progression and the acquisition of resistance to therapy. Given the importance of the tumour microenvironment and cytokine signalling in PDAC, and an emerging role for the UPR in shaping the tumour microenvironment and in the regulation of cytokines in other cancer types, this review explores the importance of the UPR in PDAC biology and its potential as a therapeutic target in this disease.

Landmark Series: Neoadjuvant Treatment in Borderline Resectable Pancreatic Cancer

BACKGROUND

Borderline resectable pancreatic cancer (BRPC) is frequently encountered in high-volume centers. It has various definitions among different societies or institutions.

PATIENTS AND METHODS

In this landmark series review, we summarize the critical randomized controlled studies that have defined the neoadjuvant and surgical management of BRPC.

RESULTS

Surgical resection after neoadjuvant treatment is the mainstay of treatment and should involve margin-negative resection with regional lymphadenectomy. Several recently completed randomized controlled clinical trials have defined the role of neoadjuvant chemotherapy for patients with BRPC. The utilization of chemoradiation remains controversial.

CONCLUSIONS

The definition of BRPC goes beyond the anatomic relationship between the tumor and vessels. We need to include biological and conditional dimensions. Neoadjuvant chemotherapy and surgery are associated with improved outcomes of BRPC. Understanding the molecular features of pancreatic cancer should lead to the discovery of novel biomarkers as well as a more personalized approach to guide individualized therapy.

The RNA methyltransferase NSUN6 suppresses pancreatic cancer development by regulating cell proliferation

BACKGROUND

Pancreatic cancer (PC) is one of the most lethal solid malignancies in the world due to its excessive cell proliferation and aggressive metastatic features. Emerging evidences revealed the importance of posttranscriptional modifications of RNAs in PC progression. However, knowledge about the 5-methylcytosine (m5C) RNA modification in PC is still extremely limited. In this study, we attempted to explore the expression changes and clinical significances of 12 known m5C-related genes among PC patients.

METHODS

A total of 362 normal and 382 tumor specimens from PC patients were examined for candidate m5C-related gene and protein expression by using quantitative PCR (qPCR) and immunohistochemistry (IHC). The proliferation rate of PC cells was detected by MTS assay. Xenograft mouse models were used to assess the role of NSUN6 in PC tumor formation.

FINDINGS

Through analyzing the four Gene Expression Omnibus (GEO) databases, six m5C-related genes shown significant and consistent alterations were selected for further examination in our 3 independent PC cohorts. Finally, we identified the reduction of NSUN6 as a common feature of all PC sample sets examined. NSUN6 expression correlated with clinicopathologic parameters including T stage, and Ki67⁺ cell rate. Further assessing the transcriptional profiles of 50 PC tissues, we found biological processes associated with cell proliferation like cell cycle and G2M checkpoint were enriched in NSUN6 lower expression group. Helped by in vitro PC cell lines and in vivo xenograft mouse models, we confirmed the role of NSUN6 in regulating cell proliferation and PC tumor growth. Last but also importantly, we also show the good performance of NSUN6 in evaluating tumor recurrence and survival among PC patients.

INTERPRETATION

Our data suggested that NSUN6 is an important factor involved in regulating cell proliferation of PC, and highlights the potential of novel m5C-based clinical modalities as a therapeutic approach in PC patients.

FUNDING

This study was supported by the National Natural Science Foundation of China (Grant Nos. 81803014, 81802424, and 81802911).

Design, synthesis and biological evaluation of second-generation benzoylpiperidine derivatives as reversible monoacylglycerol lipase (MAGL) inhibitors

An interesting enzyme of the endocannabinoid system is monoacylglycerol lipase (MAGL). This enzyme, which metabolizes the endocannabinoid 2-arachidonoylglycerol (2-AG), has attracted great interest due to its involvement in several physiological and pathological processes, such as cancer progression. Experimental evidences highlighted some drawbacks associated with the use of irreversible MAGL inhibitors in vivo, therefore the research field concerning reversible inhibitors is rapidly growing. In the present manuscript, the class of benzoylpiperidine-based MAGL inhibitors was further expanded and optimized. Enzymatic assays identified some compounds in the low nanomolar range and steered molecular dynamics simulations predicted the dissociation itinerary of one of the best compounds from the enzyme, confirming the observed structure-activity relationship. Biological evaluation, including assays in intact U937 cells and competitive activity-based protein profiling experiments in mouse brain membranes, confirmed the selectivity of the selected compounds for MAGL versus other components of the endocannabinoid system. An antiproliferative ability in a panel of cancer cell lines highlighted their potential as potential anticancer agents. Future studies on the potential use of these compounds in the clinical setting are also supported by the inhibition of cell growth observed both in cancer organoids derived from high grade serous ovarian cancer patients and in pancreatic ductal adenocarcinoma primary cells, which showed genetic and histological features very similar to the primary tumors.

Prognostic value of the preoperative fibrinogen-to-albumin ratio in pancreatic ductal adenocarcinoma patients undergoing R0 resection

BACKGROUND

Inflammation plays an important role in tumor progression, and growing evidence has confirmed that the fibrinogen-to-albumin ratio (FAR) is an important prognostic factor for overall survival in malignant tumors.

AIM

To investigate the prognostic significance of FAR in patients undergoing radical R0 resection of pancreatic ductal adenocarcinoma (PDAC).

METHODS

We retrospectively analyzed the data of 282 patients with PDAC who underwent radical R0 resection at The Cancer Hospital of the Chinese Academy of Medical Sciences from January 2010 to December 2019. The surv_cutpoint function of the R package survminer via RStudio software (version 1.3.1073, http://www.rstudio.org) was used to determine the optimal cut-off values of biological markers, such as preoperative FAR. The Kaplan-Meier method and log-rank tests were used for univariate survival analysis, and a Cox regression model was used for multivariate survival analysis for PDAC patients who underwent radical R0 resection.

RESULTS

The optimal cut-off value of FAR was 0.08 by the surv_cutpoint function. Higher preoperative FAR was significantly correlated with clinical symptoms (P = 0.001), tumor location (P < 0.001), surgical approaches (P < 0.001), preoperative plasma fibrinogen concentration (P < 0.001), and preoperative plasma albumin level (P < 0.001). Multivariate analysis showed that degree of tumor differentiation (P < 0.001), number of metastatic lymph nodes [hazard ratio (HR): 0.678, 95% confidence interval (CI): 0.509-0.904, P = 0.008], adjuvant therapy (HR: 1.604, 95%CI: 1.214-2.118, P = 0.001), preoperative cancer antigen 19-9 level (HR: 1.740, 95%CI: 1.288-2.352, P < 0.001), and preoperative FAR (HR: 2.258, 95%CI: 1.720-2.963, P < 0.001) were independent risk factors for poor prognosis in patients with PDAC who underwent radical R0 resection.

CONCLUSION

The increase in preoperative FAR was significantly related to poor prognosis in patients undergoing radical R0 resection for PDAC. Preoperative FAR can be used clinically to predict the prognosis of PDAC patients undergoing radical R0 resection.

"Open Sesame?": Biomarker Status of the Human Equilibrative Nucleoside Transporter-1 and Molecular Mechanisms Influencing its Expression and Activity in the Uptake and Cytotoxicity of Gemcitabine in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive tumor characterized by early invasiveness, rapid progression and resistance to treatment. For more than twenty years, gemcitabine has been the main therapy for PDAC both in the palliative and adjuvant setting. After the introduction of FOLFIRINOX as an upfront treatment for metastatic disease, gemcitabine is still commonly used in combination with nab-paclitaxel as an alternative first-line regimen, as well as a monotherapy in elderly patients unfit for combination chemotherapy. As a hydrophilic nucleoside analogue, gemcitabine requires nucleoside transporters to permeate the plasma membrane, and a major role in the uptake of this drug is played by human equilibrative nucleoside transporter 1 (hENT-1). Several studies have proposed hENT-1 as a biomarker for gemcitabine efficacy in PDAC. A recent comprehensive multimodal analysis of hENT-1 status evaluated its predictive role by both immunohistochemistry (with five different antibodies), and quantitative-PCR, supporting the use of the 10D7G2 antibody. High hENT-1 levels observed with this antibody were associated with prolonged disease-free status and overall-survival in patients receiving gemcitabine adjuvant chemotherapy. This commentary aims to critically discuss this analysis and lists molecular factors influencing hENT-1 expression. Improved knowledge on these factors should help the identification of subgroups of patients who may benefit from specific therapies and overcome the limitations of traditional biomarker studies.