Multidisciplinary standards of care and recent progress in pancreatic ductal adenocarcinoma

FOXM1: A small fox that makes more tracks for cancer progression and metastasis

Transcription factors (TFs) are indispensable for the modulation of various signaling pathways associated with normal cell homeostasis and disease conditions. Among cancer-related TFs, FOXM1 is a critical molecule that regulates multiple aspects of cancer cells, including growth, metastasis, recurrence, and stem cell features. FOXM1 also impact the outcomes of targeted therapies, chemotherapies, and immune checkpoint inhibitors (ICIs) in various cancer types. Recent advances in cancer research strengthen the cancer-specific role of FOXM1, providing a rationale to target FOXM1 for developing targeted therapies. This review compiles the recent studies describing the pivotal role of FOXM1 in promoting metastasis of various cancer types. It also implicates the contribution of FOXM1 in the modulation of chemotherapeutic resistance, antitumor immune response/immunotherapies, and the potential of small molecule inhibitors of FOXM1.

Deep Learning for Fully Automated Prediction of Overall Survival in Patients Undergoing Resection for Pancreatic Cancer: A Retrospective Multicenter Study

OBJECTIVE

To develop an imaging-derived biomarker for prediction of overall survival (OS) of pancreatic cancer by analyzing preoperative multiphase contrast-enhanced computed topography (CECT) using deep learning.

BACKGROUND

Exploiting prognostic biomarkers for guiding neoadjuvant and adjuvant treatment decisions may potentially improve outcomes in patients with resectable pancreatic cancer.

METHODS

This multicenter, retrospective study included 1516 patients with resected pancreatic ductal adenocarcinoma (PDAC) from 5 centers located in China. The discovery cohort (n=763), which included preoperative multiphase CECT scans and OS data from 2 centers, was used to construct a fully automated imaging-derived prognostic biomarker-DeepCT-PDAC-by training scalable deep segmentation and prognostic models (via self-learning) to comprehensively model the tumor-anatomy spatial relations and their appearance dynamics in multiphase CECT for OS prediction. The marker was independently tested using internal (n=574) and external validation cohorts (n=179, 3 centers) to evaluate its performance, robustness, and clinical usefulness.

RESULTS

Preoperatively, DeepCT-PDAC was the strongest predictor of OS in both internal and external validation cohorts [hazard ratio (HR) for high versus low risk 2.03, 95% confidence interval (CI): 1.50-2.75; HR: 2.47, CI: 1.35-4.53] in a multivariable analysis. Postoperatively, DeepCT-PDAC remained significant in both cohorts (HR: 2.49, CI: 1.89-3.28; HR: 2.15, CI: 1.14-4.05) after adjustment for potential confounders. For margin-negative patients, adjuvant chemoradiotherapy was associated with improved OS in the subgroup with DeepCT-PDAC low risk (HR: 0.35, CI: 0.19-0.64), but did not affect OS in the subgroup with high risk.

CONCLUSIONS

Deep learning-based CT imaging-derived biomarker enabled the objective and unbiased OS prediction for patients with resectable PDAC. This marker is applicable across hospitals, imaging protocols, and treatments, and has the potential to tailor neoadjuvant and adjuvant treatments at the individual level.

Exploiting the Potential of Photon-Counting CT in Abdominal Imaging

ABSTRACT

Photon-counting computed tomography (PCCT) imaging uses a new detector technology to provide added information beyond what can already be obtained with current CT and MR technologies. This review provides an overview of PCCT of the abdomen and focuses specifically on applications that benefit the most from this new imaging technique. We describe the requirements for a successful abdominal PCCT acquisition and the challenges for clinical translation. The review highlights work done within the last year with an emphasis on new protocols that have been tested in clinical practice. Applications of PCCT include imaging of cystic lesions, sources of bleeding, and cancers. Photon-counting CT is positioned to move beyond detection of disease to better quantitative staging of disease and measurement of treatment response.

The diagnostic significance of the ZNF gene family in pancreatic cancer: a bioinformatics and experimental study

Background: Pancreatic adenocarcinoma (PAAD) is among the most devastating of all cancers with a poor survival rate. Therefore, we established a zinc finger (ZNF) protein-based prognostic prediction model for PAAD patients. Methods: The RNA-seq data for PAAD were downloaded from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Differentially expressed ZNF protein genes (DE-ZNFs) in PAAD and normal control tissues were screened using the "lemma" package in R. An optimal risk model and an independent prognostic value were established by univariate and multivariate Cox regression analyses. Survival analyses were performed to assess the prognostic ability of the model. Results: We constructed a ZNF family genes-related risk score model that is based on the 10 DE-ZNFs (ZNF185, PRKCI, RTP4, SERTAD2, DEF8, ZMAT1, SP110, U2AF1L4, CXXC1, and RMND5B). The risk score was found to be a significant independent prognostic factor for PAAD patients. Seven significantly differentially expressed immune cells were identified between the high- and low-risk patients. Then, based on the prognostic genes, we constructed a ceRNA regulatory network that includes 5 prognostic genes, 7 miRNAs and 35 lncRNAs. Expression analysis showed ZNF185, PRKCI and RTP4 were significantly upregulated, while ZMAT1 and CXXC1 were significantly downregulated in the PAAD samples in all TCGA - PAAD, GSE28735 and GSE15471 datasets. Moreover, the upregulation of RTP4, SERTAD2, and SP110 were verified by the cell experiments. Conclusion: We established and validated a novel, Zinc finger protein family - related prognostic risk model for patients with PAAD, that has the potential to inform patient management.

Effects of anoxic prognostic model on immune microenvironment in pancreatic cancer

Pancreatic cancer has one of the worst prognoses in the world, which suggests that the tumor microenvironment, which is characterized by hypoxia and immunosuppression, plays a significant role in the prognosis and progression of pancreatic cancer. We identified PLAU, LDHA, and PKM as key genes involved in pancreatic cancer hypoxia through GO/KEGG enrichment related hypoxia pathways and cox regression, established prognostic models, and studied their relationship to immune invasion through bioinformatics using R and related online databases. We verified the high expression of PLAU, LDHA, and PKM in pancreatic cancer cells using qPCR in vitro, and we also discovered that the expression of PLAU, LDHA, and PKM in hypoxic pancreatic cancer cells differed from that in normal cultured pancreatic cancer cells. Finally, we discovered that our prognostic model accurately predicted postrain in pancreatic cancer patients with hypoxia and immune infiltration.

Atezolizumab Plus PEGPH20 Versus Chemotherapy in Advanced Pancreatic Ductal Adenocarcinoma and Gastric Cancer: MORPHEUS Phase Ib/II Umbrella Randomized Study Platform

BACKGROUND

The MORPHEUS platform comprises multiple open-label, randomized, phase Ib/II trials designed to identify early efficacy and safety signals of treatment combinations across cancers. Atezolizumab (anti-programmed cell death 1 ligand 1 [PD-L1]) was evaluated in combination with PEGylated recombinant human hyaluronidase (PEGPH20).

METHODS

In 2 randomized MORPHEUS trials, eligible patients with advanced, previously treated pancreatic ductal adenocarcinoma (PDAC) or gastric cancer (GC) received atezolizumab plus PEGPH20, or control treatment (mFOLFOX6 or gemcitabine plus nab-paclitaxel [MORPHEUS-PDAC]; ramucirumab plus paclitaxel [MORPHEUS-GC]). Primary endpoints were objective response rates (ORR) per RECIST 1.1 and safety.

RESULTS

In MORPHEUS-PDAC, ORRs with atezolizumab plus PEGPH20 (n = 66) were 6.1% (95% CI, 1.68%-14.80%) vs. 2.4% (95% CI, 0.06%-12.57%) with chemotherapy (n = 42). In the respective arms, 65.2% and 61.9% had grade 3/4 adverse events (AEs); 4.5% and 2.4% had grade 5 AEs. In MORPHEUS-GC, confirmed ORRs with atezolizumab plus PEGPH20 (n = 13) were 0% (95% CI, 0%-24.7%) vs. 16.7% (95% CI, 2.1%-48.4%) with control (n = 12). Grade 3/4 AEs occurred in 30.8% and 75.0% of patients, respectively; no grade 5 AEs occurred.

CONCLUSION

Atezolizumab plus PEGPH20 showed limited clinical activity in patients with PDAC and none in patients with GC. The safety of atezolizumab plus PEGPH20 was consistent with each agent's known safety profile. (ClinicalTrials.gov Identifier: NCT03193190 and NCT03281369).

Phase 2 study of preoperative chemotherapy with nab-paclitaxel and gemcitabine followed by chemoradiation for borderline resectable or node-positive pancreatic ductal adenocarcinoma

BACKGROUND

Neoadjuvant treatment with nab-paclitaxel and gemcitabine for potentially operable pancreatic adenocarcinoma has not been well studied in a prospective interventional trial and could down-stage tumors to achieve negative surgical margins.

METHODS

A single-arm, open-label phase 2 trial (NCT02427841) enrolled patients with pancreatic adenocarcinoma deemed to be borderline resectable or clinically node-positive from March 17, 2016 to October 5, 2019. Patients received preoperative gemcitabine 1000 mg/m2 and nab-paclitaxel 125 mg/m2 on Days 1, 8, 15, every 28 days for two cycles followed by chemoradiation with 50.4 Gy intensity-modulated radiation over 28 fractions with concurrent fluoropyrimidine chemotherapy. After definitive resection, patients received four additional cycles of gemcitabine and nab-paclitaxel. The primary endpoint was R0 resection rate. Other endpoints included treatment completion rate, resection rate, radiographic response rate, survival, and adverse events.

RESULTS

Nineteen patients were enrolled, with the majority having head of pancreas primary tumors, both arterial and venous vasculature involvement, and clinically positive nodes on imaging. Among them, 11 (58%) underwent definitive resection and eight of 19 (42%) achieved R0 resection. Disease progression and functional decline were primary reasons for deferring surgical resection after neoadjuvant treatment. Pathologic near-complete response was observed in two of 11 (18%) resection specimens. Among the 19 patients, the 12-month progression-free survival was 58%, and 12-month overall survival was 79%. Common adverse events were alopecia, nausea, vomiting, fatigue, myalgia, peripheral neuropathy, rash, and neutropenia.

CONCLUSION

Gemcitabine and nab-paclitaxel followed by long-course chemoradiation represents a feasible neoadjuvant treatment strategy for borderline resectable or node-positive pancreatic cancer.

Clinical and genetic characteristics in pancreatic cancer from Chinese patients revealed by whole exome sequencing

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal malignancies worldwide, mostly as a result of the absence of early detection and specific treatment solutions. Consequently, identifying mutational profiles and molecular biomarkers is essential for increasing the viability of precision therapy for pancreatic cancer.

METHODS

We collected blood and tumor tissue samples from 47 Chinese pancreatic cancer patients and used whole-exome sequencing (WES) to evaluate the genetic landscape.

RESULTS

Our results showed the most frequently somatic alteration genes were KRAS (74.5%), TP53(51.1%), SMAD4 (17%), ARID1A (12.8%), CDKN2A (12.8%), TENM4 (10.6%), TTN (8.5%), RNF43(8.5%), FLG (8.5%) and GAS6 (6.4%) in Chinese PDAC patients. We also found that three deleterious germline mutations (ATM c.4852C>T/p. R1618*, WRN c.1105C>T/p. R369*, PALB2 c.2760dupA/p. Q921Tfs*7) and two novel fusions (BRCA1-RPRML, MIR943 (intergenic)-FGFR3). When compared to the Cancer Genome Atlas (TCGA) database, there is a greater mutation frequency of TENM4 (10.6% vs. 1.6%, p = 0.01), GAS6(6.4% vs. 0.5%, p = 0.035), MMP17(6.4% vs. 0.5%, p = 0.035), ITM2B (6.4% vs. 0.5%, p = 0.035) and USP7 (6.4% vs. 0.5%, p= 0.035) as well as a reduced mutation frequency of SMAD4 (17.0% vs. 31.5%, p = 0.075) and CDKN2A (12.8% vs. 47.3%, p < 0.001) were observed in the Chinese cohort. Among the 41 individuals examined for programmed cell death ligand 1(PD-L1) expression, 15 (36.6%) had positive PD-L1 expression. The median tumor mutational burden (TMB) was found to be 12muts (range, 0124). The TMB index was higher in patients with mutant-type KRAS MUT/TP53 MUT (p < 0.001), CDKN2A (p = 0.547), or SMAD4 (p = 0.064) compared to patients with wild-type KRAS/TP53, CDKN2A, or SMAD4.

CONCLUSIONS

We exhibited real-world genetic traits and new alterations in Chinese individuals with cancer of the pancreas, which might have interesting implications for future individualized therapy and medication development.

A network pharmacology-based investigation of emodin against pancreatic adenocarcinoma

Pancreatic adenocarcinoma (PAAD) is one of the most common malignancies worldwide with an increasing incidence and poor outcome due to the lack of effective diagnostic and treatment methods. Emerging evidence implicates that emodin displays extensive spectrum anticancer properties. Differential expression genes in PAAD patients were analyzed by Gene Expression Profiling Interactive Analysis (GEPIA) website, and the targets of emodin were obtained via Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. Subsequently, enrichment analyses were performed using R software. A protein-protein interaction (PPI) network was constructed by STRING database and Cytoscape software was used to identify the hub genes. Prognostic value and immune infiltration landscapes were explored through Kaplan-Meier plotter (KM plotter) website and the Single-Sample Gene Set Enrichment Analysis package of R. Finally, molecular docking was used to computationally verify the interaction of ligand and receptor proteins. A total of 9191 genes were significantly differentially expressed in PAAD patients and 34 potential targets of emodin were obtained. Intersections of the 2 groups were considered as potential targets of emodin against PAAD. Functional enrichment analyses illustrated that these potential targets were linked to numerous pathological processes. Hub genes identified through PPI networks were correlated with poor prognosis and infiltration level of different immune cells in PAAD patients. Perhaps emodin interacted with the key molecules and regulate the activity of them. We revealed the inherent mechanism of emodin against PAAD with the aid of network pharmacology, which provided reliable evidence and a novel guideline for clinical treatment.

Genome instability-related LINC02577, LINC01133 and AC107464.2 are lncRNA prognostic markers correlated with immune microenvironment in pancreatic adenocarcinoma

BACKGROUND

Pancreatic adenocarcinoma (PAAD) is a leading cause of malignancy-related deaths worldwide, and the efficacy of immunotherapy on PAAD is limited. Studies report that long non-coding RNAs (lncRNAs) play an important role in modulating genomic instability and immunotherapy. However, the identification of genome instability-related lncRNAs and their clinical significance has not been investigated in PAAD.

METHODS

The current study developed a computational framework for mutation hypothesis based on lncRNA expression profile and somatic mutation spectrum in pancreatic adenocarcinoma genome. We explored the potential of GInLncRNAs(genome instability-related lncRNAs) through co-expression analysis and function enrichment analysis. We further analyzed GInLncRNAs by Cox regression and used the results to construct a prognostic lncRNA signature. Finally, we analyzed the relationship between GILncSig (genomic instability derived 3-lncRNA signature) and immunotherapy.

RESULTS

A GILncSig was developed using bioinformatics analyses. It could divide patients into high-risk and low-risk groups, and there was a significant difference in OS between the two groups. In addition, GILncSig was associated with genome mutation rate in pancreatic adenocarcinoma, indicating its potential value as a marker for genomic instability. The GILncSig accurately grouped wild type patients of KRAS into two risk groups. The prognosis of the low-risk group was significantly improved. GILncSig was significantly correlated with the level of immune cell infiltration and immune checkpoint.

CONCLUSIONS

In summary, the current study provides a basis for further studies on the role of lncRNA in genomic instability and immunotherapy. The study provides a novel method for identification of cancer biomarkers related to genomic instability and immunotherapy.

Case Report: Early detection of pancreatic pre-cancer lesion in multimodal approach with exosome liquid biopsy

Background

The detection of pancreatic ductal adenocarcinoma (PDAC) lesions at pre-cancerous or early-stages is critical to improving patient survival. We have developed a liquid biopsy test (ExoVita^®) based on the measurement of protein biomarkers in cancer-derived exosomes. The high sensitivity and specificity of the test for early-stage PDAC has the potential to improve a patient's diagnostic journey in hopes to impact patient outcomes.

Methods

Exosome isolation was performed using alternating current electric (ACE) field applied to the patient plasma sample. Following a wash to eliminate unbound particles, the exosomes were eluted from the cartridge. A downstream multiplex immunoassay was performed to measure proteins of interest on the exosomes, and a proprietary algorithm provided a score for probability of PDAC.

Results

We describe the case of a 60-year-old healthy non-Hispanic white male with acute pancreatitis who underwent numerous invasive diagnostic procedures that failed to detect radiographic evidence of pancreatic lesions. Following the results of our exosome-based liquid biopsy test showing "High Likelihood of PDAC", in addition to KRAS and TP53 mutations, the patient decided to undergo a robotic pancreaticoduodenectomy (Whipple) procedure. Surgical pathology confirmed the diagnosis of high-grade intraductal papillary mucinous neoplasm (IPMN), which was consistent with the results of our ExoVita^® test. The patient's post-operative course was unremarkable. At five-month follow-up, the patient continued to recover well without complications, in addition to a repeat ExoVita test which demonstrated "Low Likelihood of PDAC".

Conclusion

This case report highlights how a novel liquid biopsy diagnostic test based on the detection of exosome protein biomarkers allowed early diagnosis of a high-grade precancerous lesion for PDAC and improved patient outcome.

Dissecting metastasis using preclinical models and methods

Metastasis has long been understood to lead to the overwhelming majority of cancer-related deaths. However, our understanding of the metastatic process, and thus our ability to prevent or eliminate metastases, remains frustratingly limited. This is largely due to the complexity of metastasis, which is a multistep process that likely differs across cancer types and is greatly influenced by many aspects of the in vivo microenvironment. In this Review, we discuss the key variables to consider when designing assays to study metastasis: which source of metastatic cancer cells to use and where to introduce them into mice to address different questions of metastasis biology. We also examine methods that are being used to interrogate specific steps of the metastatic cascade in mouse models, as well as emerging techniques that may shed new light on previously inscrutable aspects of metastasis. Finally, we explore approaches for developing and using anti-metastatic therapies, and how mouse models can be used to test them.

Current Approaches for the Curative-Intent Surgical Treatment of Pancreatic Ductal Adenocarcinoma

Radical resection is the only curative treatment for pancreatic cancer. However, only up to 20% of patients are considered eligible for surgical resection at the time of diagnosis. Although upfront surgery followed by adjuvant chemotherapy has become the gold standard of treatment for resectable pancreatic cancer there are numerous ongoing trials aiming to compare the clinical outcomes of various surgical strategies (e.g., upfront surgery or neoadjuvant treatment with subsequent resection). Neoadjuvant treatment followed by surgery is considered the best approach in borderline resectable pancreatic tumors. Individuals with locally advanced disease are now candidates for palliative chemo- or chemoradiotherapy; however, some patients may become eligible for resection during the course of such treatment. When metastases are found, the cancer is qualified as unresectable. It is possible to perform radical pancreatic resection with metastasectomy in selected cases of oligometastatic disease. The role of multi-visceral resection, which involves reconstruction of major mesenteric veins, is well known. Nonetheless, there are some controversies in terms of arterial resection and reconstruction. Researchers are also trying to introduce personalized treatments. The careful, preliminary selection of patients eligible for surgery and other therapies should be based on tumor biology, among other factors. Such selection may play a key role in improving survival rates in patients with pancreatic cancer.

Pancreatic Tumor-Targeting Stemsome Therapeutics

Owing to the intrinsic ability of stem cells to target the tumor environment, stem-cell-membrane-functionalized nanocarriers can target and load active anticancer drugs. In this work, a strategy that focuses on stem cells that self-target pancreatic cancer cells is developed. In particular, malignant deep tumors such as pancreatic cancer cells, one of the intractable tumors that currently have no successful clinical strategy, are available for targeting and destruction. By gaining the targeting ability of stem cells against pancreatic tumor cells, stem cell membranes can encapsulate nano-polylactide-co-glycolide loaded with doxorubicin to target and reduce deep pancreatic tumor tissues. Considering the lack of known target proteins on pancreatic tumor cells, the suggested platform technology can be utilized for targeting any malignant tumors in which surface target receptors are unavailable.

The "Self-eating" of cancer-associated fibroblast: A potential target for cancer

Autophagy helps maintain energy homeostasis and protect cells from stress effects by selectively removing misfolded/polyubiquitylated proteins, lipids, and damaged mitochondria. Cancer-associated fibroblasts (CAFs) are cellular components of tumor microenvironment (TME). Autophagy in CAFs inhibits tumor development in the early stages; however, it has a tumor-promoting effect in advanced stages. In this review, we aimed to summarize the modulators responsible for the induction of autophagy in CAFs, such as hypoxia, nutrient deprivation, mitochondrial stress, and endoplasmic reticulum stress. In addition, we aimed to present autophagy-related signaling pathways in CAFs, and role of autophagy in CAF activation, tumor progression, tumor immune microenvironment. Autophagy in CAFs may be an emerging target for tumor therapy. In summary, autophagy in CAFs is regulated by a variety of modulators and can reshape tumor immune microenvironment, affecting tumor progression and treatment.

Survival Outcomes and Failure Patterns in Patients with Inoperable Non-Metastatic Pancreatic Cancer Treated with Definitive Radiotherapy

This study investigated the long-term results, failure patterns, and prognostic factors of patients with initially inoperable non-metastatic pancreatic cancer (PC) receiving definitive radiotherapy (RT). Between January 2016 and December 2020, a total of 168 non-metastatic PC patients, who were surgically unresectable or medically inoperable, were enrolled to receive definitive RT, with or without chemotherapy. Overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan-Meier method with a log-rank test. The cumulative incidence of locoregional and distant progression was estimated using the competing risks model. The Cox proportional-hazards model was used to determine the influence of prognostic variables on OS. With a median follow-up of 20.2 months, the median OS (mOS) and median PFS (mPFS) from diagnosis were 18.0 months [95% confidence interval (CI), 16.5-21.7 months] and 12.3 months (95% CI, 10.2-14.3 months), respectively. The mOS and mPFS from RT were 14.3 months (95% CI, 12.7-18.3 months) and 7.7 months (95% CI, 5.5-12.0 months), respectively. The corresponding 1-year, 2-year, and 3-year OS from diagnosis and RT were 72.1%, 36.6%, and 21.5% as well as 59.0%, 28.8%, and 19.0%, respectively. In a multivariate analysis, stage I-II (p = 0.032), pre-RT CA19-9 ≤ 130 U/mL (p = 0.011), receiving chemotherapy (p = 0.003), and a biologically effective dose (BED₁₀) > 80 Gy (p = 0.014) showed a significant favorable influence on OS. Among the 59 available patients with definite progression sites, the recurrences of local, regional, and distant progression were 33.9% (20/59), 18.6% (11/59), and 59.3% (35/59), respectively. The 1-year and 2-year cumulative incidences of locoregional progression after RT were 19.5% (95% CI, 11.5-27.5%) and 32.8% (95% CI, 20.8-44.8%), respectively. Definitive RT was associated with long-term primary tumor control, resulting in superior survival in patients with inoperable non-metastatic PC. Further prospective randomized trials are warranted to validate our results in these patients.

New therapy for pancreatic cancer based on extracellular vesicles

Pancreatic Ductal Adenocarcinoma (PDAC), is the most common aggressive cancer of the pancreas. The standard care of PDAC includes tumor resection and chemotherapy, but the lack of early diagnosis and the limited response to the treatment worsens the patient's condition. In order to improve the efficiency of chemotherapy, we look for more efficient systems of drug delivery. We isolated and fully characterized small Extracellular Vesicles (EVs) from the RWP-1 cell line. Our study indicates that the direct incubation method was the most efficient loading protocol and that a minimum total amount of drug triggers an effect on tumor cells. Therefore, we loaded the small EVs with two chemotherapeutic drugs (Temozolomide and EPZ015666) by direct incubation method and the amount of drug loaded was measured by high-performance liquid chromatography (HPLC). Finally, we tested their antiproliferative effect on different cancer cell lines. Moreover, the system is highly dependent on the drug structure and therefore RWP-1 small EVs^TMZ were more efficient than RWP-1 small EVs^EPZ015666. RWP-1 derived small EVs represent a promising drug delivery tool that can be further investigated in preclinical studies and its combination with PRMT5 inhibitor can be potentially developed in clinical trials for the treatment of PDAC.

Genomic Biomarkers Associated with Response to Induction Chemotherapy in Patients with Localized Pancreatic Ductal Adenocarcinoma

PURPOSE

There is increasing use of neoadjuvant chemotherapy in the management of localized pancreatic ductal adenocarcinoma (PDAC), yet there are few validated biomarkers to guide therapy selection. We aimed to determine whether somatic genomic biomarkers predict response to induction FOLFIRINOX or gemcitabine/nab-paclitaxel.

EXPERIMENTAL DESIGN

This single-institution cohort study included consecutive patients (N = 322) with localized PDAC (2011-2020) who received at least one cycle of FOLFIRINOX (N = 271) or gemcitabine/nab-paclitaxel (N = 51) as initial treatment. We assessed somatic alterations in four driver genes (KRAS, TP53, CDKN2A, and SMAD4) by targeted next-generation sequencing, and determined associations between these alterations and (1) rate of metastatic progression during induction chemotherapy, (2) surgical resection, and (3) complete/major pathologic response.

RESULTS

The alteration rates in driver genes KRAS, TP53, CDKN2A, and SMAD4 were 87.0%, 65.5%, 26.7%, and 19.9%, respectively. For patients receiving first-line FOLFIRINOX, SMAD4 alterations were uniquely associated with metastatic progression (30.0% vs. 14.5%; P = 0.009) and decreased rate of surgical resection (37.1% vs. 66.7%; P < 0.001). For patients receiving induction gemcitabine/nab-paclitaxel, alterations in SMAD4 were not associated with metastatic progression (14.3% vs. 16.2%; P = 0.866) nor decreased rate of surgical resection (33.3% vs. 41.9%; P = 0.605). Major pathologic response was rare (6.3%) and not associated with type of chemotherapy regimen.

CONCLUSIONS

SMAD4 alterations were associated with more frequent development of metastasis and lower probability of reaching surgical resection during neoadjuvant FOLFIRINOX but not gemcitabine/nab-paclitaxel. Confirmation in a larger, diverse patient cohort will be important before prospective evaluation of SMAD4 as a genomic biomarker to guide treatment selection.

Circulating gamma-glutamyl transpeptidase and risk of pancreatic cancer: A prospective cohort study in the UK Biobank

BACKGROUND

To determine whether serum gamma-glutamyl transpeptidase (GGT) level is associated with pancreatic cancer risk in a large prospective cohort.

METHODS

The study analyzed serum GGT concentration at baseline of 421,032 participants recruited in the UK Biobank since 2006 through 2010. Information on incidence of pancreatic cancer was obtained from cancer and death registers, updated until 2015 in Scotland or 2016 in England and Wales. Adjusted Cox proportional hazards models were used to measure the association between serum GGT and pancreatic cancer risk.

RESULTS

The study identified 586 cases of pancreatic cancer over a median follow-up period of 7.16 years. In the multivariable-adjusted Cox model, serum GGT level was associated with 14% higher pancreatic cancer risk (hazard ratio (HR) per one standard deviation increment of log2 GGT level = 1.14, 95% confidence interval (CI) 1.02-1.28, p = 0.025). In the total population, the HR for the highest GGT group was 1.68 (95%CI: 1.22-2.30) versus the lowest GGT group. The HR for the highest GGT group in men (≥50.2 U/L) was 1.72 (95%CI: 1.14-2.61) and that in women (≥31.6 U/L) was 1.75 (95%CI: 1.06-2.88) versus the lowest GGT group.

CONCLUSION

Our findings suggested a positive association of serum GGT in pancreatic cancer etiology, implying the potential of monitoring GGT level for identifying at-risk individuals for pancreatic cancer.

The diverse pancreatic tumor cell-intrinsic response to IFNγ is determined by epigenetic heterogeneity

IFNγ signaling is mainly mediated through the activation of the canonical JAK-STAT signaling pathway, transcription factors, and epigenetic modifications. The activation of IFNγ signaling pathway may provide a novel option for tumor immunotherapy, but the outcomes remain controversial. In fact, recent studies suggest that the resistance to IFNγ-dependent immunotherapies is commonly derived from the tumor cell-intrinsic heterogeneity, the molecular mechanism of which remains elusive. Therefore, elucidating the tumor cell-intrinsic heterogeneity in response to IFNγ would be beneficial to improve the efficacy of immunotherapy. Here, we first delineated the epigenetic redistribution and transcriptome alteration in response to IFNγ stimulation, and demonstrated that ectopic gain of H3K4me3 and H3K27Ac at the promoter region mainly contributed to the enhancement of IFNγ-mediated transcriptional activity of interferon-stimulated genes (ISGs). Furthermore, we found that the cellular heterogeneity of PD-L1 expression in response to IFNγ was mainly attributed to cell-intrinsic H3K27me3 levels. Enhancement of H3K27me3 by GSK-J4 limited PD-L1^hi tumor growth by salvaging the intratumoral cytotoxicity of CD8⁺ T cells, which may provide therapeutic strategies to overcome immune escape and resistance to IFNγ-based immunotherapies in pancreatic cancer.

Targeting tumor immunosuppressive microenvironment for pancreatic cancer immunotherapy: Current research and future perspective

Pancreatic cancer is one of the most malignant tumors with increased incidence rate. The effect of surgery combined with chemoradiotherapy on survival of patients is unsatisfactory. New treatment strategy such as immunotherapy need to be investigated. The accumulation of desmoplastic stroma, infiltration of immunosuppressive cells including myeloid derived suppressor cells (MDSCs), tumor associated macrophages (TAMs), cancer‐associated fibroblasts (CAFs), and regulatory T cells (Tregs), as well as tumor associated cytokine such as TGF-β, IL-10, IL-35, CCL5 and CXCL12 construct an immunosuppressive microenvironment of pancreatic cancer, which presents challenges for immunotherapy. In this review article, we explore the roles and mechanism of immunosuppressive cells and lymphocytes in establishing an immunosuppressive tumor microenvironment in pancreatic cancer. In addition, immunotherapy strategies for pancreatic cancer based on tumor microenvironment including immune checkpoint inhibitors, targeting extracellular matrix (ECM), interfering with stromal cells or cytokines in TME, cancer vaccines and extracellular vesicles (EVs) are also discussed. It is necessary to identify an approach of immunotherapy in combination with other modalities to produce a synergistic effect with increased response rates in pancreatic cancer therapy.

Vacuolar protein sorting 35 (VPS35) acts as a tumor promoter via facilitating cell cycle progression in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is insidious and highly malignant with extremely poor prognosis and drug resistance to current chemotherapies. Therefore, there is a critical need to investigate the molecular mechanism underlying PDAC progression to develop promising diagnostic and therapeutic interventions. In parallel, vacuolar protein sorting (VPS) proteins, involved in the sorting, transportation, and localization of membrane proteins, have gradually attracted the attention of researchers in the development of cancers. Although VPS35 has been reported to promote carcinoma progression, the specific molecular mechanism is still unclear. Here, we determined the impact of VPS35 on the tumorigenesis of PDAC and explored the underlying molecular mechanism. We performed a pan-cancer analysis of 46 VPS genes using RNAseq data from GTEx (control) and TCGA (tumor) and predicted potential functions of VPS35 in PDAC by enrichment analysis. Furthermore, cell cloning experiments, gene knockout, cell cycle analysis, immunohistochemistry, and other molecular and biochemical experiments were used to validate the function of VPS35. Consequently, VPS35 was found overexpressed in multiple cancers and correlated with the poor prognosis of PDAC. Meanwhile, we verified that VPS35 could modulate the cell cycle and promote tumor cell growth in PDAC. Collectively, we provide solid evidence that VPS35 facilitates the cell cycle progression as a critical novel target in PDAC clinical therapy.

A novel cuproptosis-related gene model predicts outcomes and treatment responses in pancreatic adenocarcinoma

BACKGROUND

Cuproptosis is recently emerging as a hot spot in cancer research. However, its role in pancreatic adenocarcinoma (PAAD) has not yet been clarified. This study aimed to explore the prognostic and therapeutic implications of cuproptosis-related genes in PAAD.

METHODS

Two hundred thirteen PAAD samples from the International Cancer Genome Consortium (ICGC) were split into training and validation sets in the ratio of 7:3. The Cox regression analyses generated a prognostic model using the ICGC cohort for training (n = 152) and validation (n = 61). The model was externally tested on the Gene Expression Omnibus (GEO) (n = 80) and The Cancer Genome Atlas (TCGA) datasets (n = 176). The clinical characteristics, molecular mechanisms, immune landscape, and treatment responses in model-defined subgroups were explored. The expression of an independent prognostic gene TSC22D2 was confirmed by public databases, real-time quantitative PCR (RT-qPCR), western blot (WB), and immunohistochemistry (IHC).

RESULTS

A prognostic model was established based on three cuproptosis-related genes (TSC22D2, C6orf136, PRKDC). Patients were stratified into high- and low-risk groups using the risk score based on this model. PAAD patients in the high-risk group had a worse prognosis. The risk score was statistically significantly correlated with most clinicopathological characteristics. The risk score based on this model was an independent predictor of overall survival (OS) (HR = 10.7, p < 0.001), and was utilized to create a scoring nomogram with excellent prognostic value. High-risk patients had a higher TP53 mutation rate and a superior response to multiple targeted therapies and chemotherapeutic drugs, but might obtain fewer benefits from immunotherapy. Moreover, elevated TSC22D2 expression was discovered to be an independent prognostic predictor for OS (p < 0.001). Data from public databases and our own experiments showed that TSC22D2 expression was significantly higher in pancreatic cancer tissues/cells compared to normal tissues/cells.

CONCLUSION

This novel model based on cuproptosis-related genes provided a robust biomarker for predicting the prognosis and treatment responses of PAAD. The potential roles and underlying mechanisms of TSC22D2 in PAAD need further explored.

Single-cell and bulk RNA sequencing identifies T cell marker genes score to predict the prognosis of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the lethal malignancies, with limited biomarkers identified to predict its prognosis and treatment response of immune checkpoint blockade (ICB). This study aimed to explore the predictive ability of T cell marker genes score (TMGS) to predict their overall survival (OS) and treatment response to ICB by integrating single-cell RNA sequencing (scRNA-seq) and bulk RNA-seq data. Multi-omics data of PDAC were applied in this study. The uniform manifold approximation and projection (UMAP) was utilized for dimensionality reduction and cluster identification. The non-negative matrix factorization (NMF) algorithm was applied to molecular subtypes clustering. The Least Absolute Shrinkage and Selection Operator (LASSO)-Cox regression was adopted for TMGS construction. The prognosis, biological characteristics, mutation profile, and immune function status between different groups were compared. Two molecular subtypes were identified via NMF: proliferative PDAC (C1) and immune PDAC (C2). Distinct prognoses and biological characteristics were observed between them. TMGS was developed based on 10 T cell marker genes (TMGs) through LASSO-Cox regression. TMGS is an independent prognostic factor of OS in PDAC. Enrichment analysis indicated that cell cycle and cell proliferation-related pathways are significantly enriched in the high-TMGS group. Besides, high-TMGS is related to more frequent KRAS, TP53, and CDKN2A germline mutations than the low-TMGS group. Furthermore, high-TMGS is significantly associated with attenuated antitumor immunity and reduced immune cell infiltration compared to the low-TMGS group. However, high TMGS is correlated to higher tumor mutation burden (TMB), a low expression level of inhibitory immune checkpoint molecules, and a low immune dysfunction score, thus having a higher ICB response rate. On the contrary, low TMGS is related to a favorable response rate to chemotherapeutic agents and targeted therapy. By combining scRNA-seq and bulk RNA-seq data, we identified a novel biomarker, TMGS, which has remarkable performance in predicting the prognosis and guiding the treatment pattern for patients with PDAC.

Histone Modifications Represent a Key Epigenetic Feature of Epithelial-to-Mesenchyme Transition in Pancreatic Cancer

Pancreatic cancer is one of the most lethal malignant diseases due to its high invasiveness, early metastatic properties, rapid disease progression, and typically late diagnosis. Notably, the capacity for pancreatic cancer cells to undergo epithelial-mesenchymal transition (EMT) is key to their tumorigenic and metastatic potential, and is a feature that can explain the therapeutic resistance of such cancers to treatment. Epigenetic modifications are a central molecular feature of EMT, for which histone modifications are most prevalent. The modification of histones is a dynamic process typically carried out by pairs of reverse catalytic enzymes, and the functions of these enzymes are increasingly relevant to our improved understanding of cancer. In this review, we discuss the mechanisms through which histone-modifying enzymes regulate EMT in pancreatic cancer.

Associations between genetically predicted levels of blood metabolites and pancreatic cancer risk

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive solid malignancies, which is featured by systematic metabolism. Thus, a better understanding of metabolic dysregulation in PDAC is important to better characterize its etiology. Here, we performed a large metabolome-wide association study (MWAS) to systematically explore associations between genetically predicted metabolite levels in blood and PDAC risk. Using data from 881 subjects of European descent in the TwinsUK Project, comprehensive genetic models were built to predict serum metabolite levels. These prediction models were applied to the genetic data of 8275 cases and 6723 controls included in the PanScan (I, II and III) and PanC4 consortia. After assessing the metabolite-PDAC risk associations by a slightly modified TWAS/FUSION framework, we identified five metabolites (including two dipeptides) showing significant associations with PDAC risk at false discovery rate (FDR) <0.05. Integrated with gut microbial information, two-sample Mendelian randomization (MR) analyses were further performed to investigate the relationship among serum metabolites, gut microbiome features and PDAC. The flavonoid-degrading bacteria Flavonifractor sp90199495 was found to be associated with metabolite X-21849 and it was also shown to be associated with PDAC risk. Collectively, our study identified novel candidate metabolites for PDAC risk, which could lead to new insights into the etiology of PDAC and improved treatment options.

Role of contrast-enhanced ultrasound with time-intensity curve analysis for differentiating hypovascular solid pancreatic lesions

OBJECTIVES

To evaluate the clinical value of contrast-enhanced ultrasound (CEUS) with time-intensity curve (TIC) in distinguishing different types of hypovascular solid pancreatic lesions.

METHODS

A total of 89 patients with 90 pancreatic lesions (all confirmed by surgery or biopsy pathology) that manifested hypoenhancement on contrast-enhanced ultrasound (CEUS) were included in this study. Six peak enhancement patterns were proposed for differentiating hypovascular pancreatic lesions. CEUS qualitative and TIC-based quantitative parameters were analyzed, and each lesion was scored based on the statistically significant qualitative parameters to evaluate the diagnostic ability of CEUS for hypovascular solid pancreatic lesions.

RESULTS

Qualitative parameters such as peak enhancement pattern II/III/IV, penetrating vessels, centripetal enhancement, and early washout were reliable indicators of malignant lesions, and lesions scored based on these qualitative parameters, with a score ≥ 2, were highly suspected to be malignant lesions. Pattern I had an accuracy of 83.33% for predicting mass-forming pancreatitis (MFP), pattern V had an accuracy of 96.67% for predicting solid pseudopapillary tumors of the pancreas (SPTP), and pattern VI had an accuracy of 81.11% for predicting neuroendocrine tumors/carcinomas (NETs/NECs). For quantitative analysis, nodule/pancreatic parenchyma echo intensity reduction ratio was significantly greater in malignant lesions.

CONCLUSIONS

CEUS qualitative and TIC-based quantitative parameters have clinical value in distinguishing malignant from benign hypovascular pancreatic lesions.

KEY POINTS

• Contrast-enhanced ultrasound helps clinicians assess patients with pancreatic lesions. • Six peak enhancement patterns are proposed for differentiating pancreatic hypovascular lesions. • Qualitative parameters such as peak enhancement pattern II/III/IV, penetrating vessels, centripetal enhancement, early washout, and quantitative parameter nodule/pancreatic parenchyma echo intensity reduction ratio were important characteristics to discriminate malignant from hypovascular benign lesions.

LncRNA SNHG6 Upregulates KPNA5 to Overcome Gemcitabine Resistance in Pancreatic Cancer via Sponging miR-944

Gemcitabine (GEM) is the gold-standard therapeutic regimen for patients with pancreatic cancer (PC); however, patients may receive limited benefits due to the drug resistance of GEM. LncRNA SNHG6 is reported to play key roles in drug resistance, but its role and molecular mechanism in PC remain incompletely understood. We found that LncRNA SNHG6 is drastically downregulated in GEM-resistant PC and is positively correlated with the survival of PC patients. With the help of bioinformatic analysis and molecular approaches, we show that LncRNA SNHG6 can sponge miR-944, therefore causing the upregulation of the target gene KPNA5. In vitro experiments showed that LncRNA SNHG6 and KPNA5 suppress PC cell proliferation and colony formation. The Upregulation of LncRNA SNHG6 and KPNA5 increases the response of GEM-resistant PANC-1 cells to GEM. We also show that the expression of KPNA5 is higher in patients without GEM resistance than in those who developed GEM resistance. In summary, our findings indicate that the LncRNA SNHG6/miR944/KPNA5 axis plays a pivotal role in overcoming GEM resistance, and targeting this axis may contribute to an increasing of the benefits of PC patients from GEM treatment.

Therapeutic Strategies to Overcome Fibrotic Barriers to Nanomedicine in the Pancreatic Tumor Microenvironment

Pancreatic cancer is notorious for its dismal prognosis. The enhanced permeability and retention (EPR) effect theory posits that nanomedicines (therapeutics in the size range of approximately 10-200 nm) selectively accumulate in tumors. Nanomedicine has thus been suggested to be the "magic bullet"-both effective and safe-to treat pancreatic cancer. However, the densely fibrotic tumor microenvironment of pancreatic cancer impedes nanomedicine delivery. The EPR effect is thus insufficient to achieve a significant therapeutic effect. Intratumoral fibrosis is chiefly driven by aberrantly activated fibroblasts and the extracellular matrix (ECM) components secreted. Fibroblast and ECM abnormalities offer various potential targets for therapeutic intervention. In this review, we detail the diverse strategies being tested to overcome the fibrotic barriers to nanomedicine in pancreatic cancer. Strategies that target the fibrotic tissue/process are discussed first, which are followed by strategies to optimize nanomedicine design. We provide an overview of how a deeper understanding, increasingly at single-cell resolution, of fibroblast biology is revealing the complex role of the fibrotic stroma in pancreatic cancer pathogenesis and consider the therapeutic implications. Finally, we discuss critical gaps in our understanding and how we might better formulate strategies to successfully overcome the fibrotic barriers in pancreatic cancer.

Pancreatic stellate cell-induced gemcitabine resistance in pancreatic cancer is associated with LDHA- and MCT4-mediated enhanced glycolysis

BACKGROUND

Profound resistance to chemotherapy remains a major challenge in achieving better clinical outcomes for patients with pancreatic ductal adenocarcinoma (PDAC). Recent studies indicate that gemcitabine (GEM) resistance is promoted both by pancreatic stellate cells (PSCs) and through increased glycolysis. However, it remains unknown whether PSCs affect GEM sensitivity via glycolytic regulation.

METHODS

Human pancreatic cancer cell (PCC) lines (BxPC-3, Capan-2, HPAF-II, Mia PaCa-2, Panc-1, SW-1990) were exposed to three different PSC-conditioned media (PSC-CM; PSC-1, PSC-2, HPaSteC), following either pre-treatment with glycolysis inhibitor NV-5440 or transfection for transient silencing of key glycolytic regulators (LDHA and MCT4). Proliferation, glucose transport, extracellular lactate, and GEM sensitivity were assessed. Protein expression was determined by Western blot and immunostaining. Moreover, secreted proteins in PSC-CMs were profiled by mass spectrometry (MS).

RESULTS

While exposure to PSC-CMs did not affect glucose transport in PCCs, it increased their lactate release and proliferation, and reduced the sensitivity for GEM. Both NV-5440 treatment and transient silencing of LDHA and MCT4 inhibited these PSC-induced changes in PCCs. MS analysis identified 688 unique proteins with differential expression, of which only 87 were common to the three PSC-CMs. Most PSC-secreted proteins were extracellular matrix-related, including SPARC, fibronectin, and collagens. Moreover, exposure to PSC-CMs increased the phosphorylation of ERK in PCCs, but the treatment of PCCs with the MEK/ERK inhibitor PD98059 resulted in a reduction of PSC-CM-induced glycolysis and improved GEM sensitivity.

CONCLUSIONS

The study findings suggest that PSC-secreted factors promote both glycolysis and GEM resistance in PCCs, and that glycolysis inhibition by NV-5440 and blocking of ERK phosphorylation by PD98059 protect PCCs from PSC-CM-induced loss of GEM sensitivity. Taken together, PSCs appear to promote GEM resistance in PDAC via glycolysis. Thus, targeting glycolysis may improve the effect of chemotherapy in PDAC.

Survival benefits and disparities in radiation therapy for elderly patients with pancreatic ductal adenocarcinoma

BACKGROUND

Older patients represent a unique subgroup of the cancer patient population, for which the role of cancer therapy requires special consideration. However, the outcomes of radiation therapy (RT) in elderly patients with pancreatic ductal adenocarcinoma (PDAC) are not well-defined in the literature.

AIM

To explore the use and effectiveness of RT in the treatment of elderly patients with PDAC in clinical practice.

METHODS

Data from patients with PDAC aged ≥ 65 years between 2004 and 2018 were collected from the Surveillance, Epidemiology, and End Results database. Multivariate logistic regression analysis was performed to determine factors associated with RT administration. Overall survival (OS) and cancer-specific survival (CSS) were evaluated using the Kaplan–Meier method with the log-rank test. Univariate and multivariate analyses with the Cox proportional hazards model were used to identify prognostic factors for OS. Propensity score matching (PSM) was applied to balance the baseline characteristics between the RT and non-RT groups. Subgroup analyses were performed based on clinical characteristics.

RESULTS

A total of 12245 patients met the inclusion criteria, of whom 2551 (20.8%) were treated with RT and 9694 (79.2%) were not. The odds of receiving RT increased with younger age, diagnosis in an earlier period, primary site in the head, localized disease, greater tumor size, and receiving chemotherapy (all P < 0.05). Before PSM, the RT group had better outcomes than did the non-RT group [median OS, 14.0 vs 6.0 mo; hazard ratio (HR) for OS: 0.862, 95% confidence interval (CI): 0.819–0.908, P < 0.001; and HR for CSS: 0.867, 95%CI: 0.823–0.914, P < 0.001]. After PSM, the survival benefit associated with RT remained comparable (median OS: 14.0 vs 11.0 mo; HR for OS: 0.818, 95%CI: 0.768–0.872, P < 0.001; and HR for CSS: 0.816, 95%CI: 0.765–0.871, P < 0.001). Subgroup analysis revealed that the survival benefits (OS and CSS) of RT were more significant in patients aged 65 to 80 years, in regional and distant stages, with no surgery, and receiving chemotherapy.

CONCLUSION

RT improved the outcome of elderly patients with PDAC, particularly those aged 65 to 80 years, in regional and distant stages, with no surgery, and who received chemotherapy. Further prospective studies are warranted to validate our results.

A four oxidative stress gene prognostic model and integrated immunity-analysis in pancreatic adenocarcinoma

BACKGROUND AND AIMS

Pancreatic adenocarcinoma (PAAD) is highly aggressive and characterized by a poor prognosis. Oxidative stress has great impacts on the occurrence and development of tumors. However, the predictive role of oxidative stress related genes on PAAD patients' prognosis remains unclear. In this study, we aimed to construct a prognostic model for PAAD based on oxidative stress genes and to evaluate its predictive value.

METHODS

The Cancer Genome Atlas (TCGA) and three Gene Expression Omnibus (GEO) datasets were used to identify differentially expressed oxidative stress genes. Univariate Cox regression, Kaplan-Meier and multivariate Cox regression analysis were used to select genes and to construct a prognosis model. According to the median value of the model's risk score, patients were divided into high and low risk groups, and gene set enrichment analysis (GSEA), immune infiltration and immunotherapy effect, drug resistance and the expression of immune checkpoint related genes and synthetic driver genes of T cell proliferation were analyzed. Finally, the mRNA and protein levels of four genes in PAAD were verified by the clinical proteomic tumor analysis consortium (CPTAC) database and the immunostaining of patients' tissue.

RESULTS

55 differentially expressed oxidative stress genes were identified, and four genes including MET, FYN, CTTN and CDK1 were selected to construct a prognosis model. GESA indicated that immune related pathways, metabolic pathways and DNA repair pathways were significantly enriched in the high risk group as compared to the low risk group. The frequency of genetic mutations was also significantly higher in high risk groups than that in low risk groups. Moreover, the infiltration level of 23 immune cells as well as the expression of immune checkpoint related and synthetic driver genes of T cell proliferation were significantly altered, with the better immunotherapy effect occurring in low risk group. In patient PAAD tissues, the mRNA and protein levels of these four genes were up-regulated.

CONCLUSION

We have successfully constructed a four oxidative stress gene prognostic model that has important predictive value for PAAD patients, and this model might be a promising guidance for prognostic prediction and efficacy monitoring in clinical individualized therapy.

Role of Surgery for Pancreatic Ductal Adenocarcinoma in the Era of Multidisciplinary Treatment

The incidence and mortality rates of pancreatic ductal adenocarcinoma (PDAC) have increased in recent years worldwide [...].

PLAGL1 is associated with prognosis and cell proliferation in pancreatic adenocarcinoma

BACKGROUND

Emerging evidence has shown the crucial roles of pleomorphic adenoma gene (PLAG) family genes in multiple cancers. However, their functions and mechanisms in pancreatic adenocarcinoma (PAAD) remain poorly understood.

METHODS

We analyzed the expression levels of PLAG family genes in both The Cancer Genome Atlas (TCGA) database and a Gene Expression Omnibus (GEO) database, and confirmed the results in our three independent cohorts of 382 PAAD tissues and 362 adjacent nontumor pancreatic tissues. Integrated analyses were carried out to explore the function, mechanism and prognostic value of the selected PLAG family gene in PAAD patients.

RESULTS

By analyzing the TCGA and GEO databases, PLAGL1 was identified to be downregulated in PAAD tissues, and its decreasing levels of both mRNA and protein were verified in our three independent PAAD cohorts. PLAGL1 expression was inversely correlated with clinicopathological factors including the Ki67⁺ cell rate and pathologic stage. Further GSEA of the TCGA-PAAD cohort demonstrated that multiple signaling pathways implicated in cell proliferation were enriched in the lower PLAGL1 expressing PAAD group. Moreover, we demonstrated that PLAGL1 expression was obviously negatively associated with patients' overall survival outcome in both the TCGA-PAAD cohort and our verification cohorts. Additionally, through MTS and BrdU assays, we further demonstrated in vitro that PLAGL1 had the impact of preventing the proliferation of pancreatic cancer cells.

CONCLUSIONS

Our present study suggested that downregulated PLAGL1 might act as a biomarker in predicts poor prognosis and one of important factors in increasing cell proliferation in PAAD. This study provides us with a novel prognostic marker and therapeutic strategy for PAAD, which deserves further study.

Development and validation of an MRI-radiomics nomogram for the prognosis of pancreatic ductal adenocarcinoma

Objective

To develop and validate an MRI-radiomics nomogram for the prognosis of pancreatic ductal adenocarcinoma (PDAC).

Background

"Radiomics" enables the investigation of huge amounts of radiological features in parallel by extracting high-throughput imaging data. MRI provides better tissue contrast with no ionizing radiation for PDAC.

Methods

There were 78 PDAC patients enrolled in this study. In total, there were 386 radiomics features extracted from MRI scan, which were screened by the least absolute shrinkage and selection operator algorithm to develop a risk score. Cox multivariate regression analysis was applied to develop the radiomics-based nomogram. The performance was assessed by discrimination and calibration.

Results

The radiomics-based risk-score was significantly associated with PDAC overall survival (OS) (P < 0.05). With respect to survival prediction, integrating the risk score, clinical data and TNM information into the nomogram exhibited better performance than the TNM staging system, radiomics model and clinical model. In addition, the nomogram showed fine discrimination and calibration.

Conclusions

The radiomics nomogram incorporating the radiomics data, clinical data and TNM information exhibited precise survival prediction for PDAC, which may help accelerate personalized precision treatment.

Clinical trial registration

clinicaltrials.gov, identifier NCT05313854.

Extracellular matrix is the main targeted environment in early stage of pancreatic ductal adenocarcinoma

Aim

Due to weak diagnosis and treatment of pancreatic ductal adenocarcinoma (PDAC), detection of PDAC possible biomarkers in early stage is the main aim of this study.

Background

PDAC is known as an exocrine cancer with a 5-year overall survival of 11%.

Methods

Gene expression profiles of early stage of PDAC tissue and normal tissue are downloaded from gene expression omnibus (GEO) and evaluated via GEO2R. The significant differentially expressed genes (DEGs) are investigated via protein-protein interaction (PPI) network analysis and gene ontology.

Results

Among 104 DEGs, ALB, COL1A1, COL1A2, MMP1, POSTN, PLAU, and COL3A1 were pointed out as hub nodes. "Gelatin degradation by MMP1, 2, 3, 7, 8, 9, 12, 13" group of 52 biological terms were identified as the main affected terms.

Conclusion

In conclusion, ALB, MMP1, and COL1A1 genes were highlighted as possible biomarkers of early stage of PDAC. Dysfunction of extracellular matrix was identified as a main event in patients.

The application of single-cell sequencing in pancreatic neoplasm: analysis, diagnosis and treatment

Pancreatic neoplasms, including pancreatic ductal adenocarcinoma (PDAC), intraductal papillary mucinous neoplasm (IPMN) and pancreatic cystic neoplasms (PCNs), are the most puzzling diseases. Numerous studies have not brought significant improvements in prognosis and diagnosis, especially in PDAC. One important reason is that previous studies only focused on differences between patients and healthy individuals but ignored intratumoral heterogeneity. In recent years, single-cell sequencing techniques, represented by single-cell RNA sequencing (scRNA-seq), have emerged by which researchers can analyse each cell in tumours instead of their average levels. Herein, we summarise the new current knowledge of single-cell sequencing in pancreatic neoplasms with respect to techniques, tumour heterogeneities and treatments.

Borderline Resectable Pancreatic Cancer: Challenges for Clinical Management

Background

Pancreatic ductal adenocarcinoma (PDAC) remains a significant worldwide health problem with a poor prognosis. A borderline resectable pancreatic ductal adenocarcinoma (BR-PDAC) is a tumor with limited vascular involvement that is technically resectable but with a high risk of positive margins (R1 resection).

Objective

To identify the current challenges that exist in the management of BR-PDAC.

Methods

A review of the literature was conducted to identify articles discussing the definitions and management of BR-PDAC.

Key Findings

Several anatomic definitions of BR-PDAC exist, and there is significant heterogeneity in their utilization across published trials. To improve the odds of a margin negative (R0) resection, a neoadjuvant treatment approach involving chemotherapy with or without radiation is currently preferred. While supporting the efficacy of a neoadjuvant approach in BR-PDAC, the largest published randomized trials have utilized older gemcitabine-based regimens. Recently published Phase II evidence and meta-analyses have supported the use of modern multi-agent regimens such as FOLFIRINOX. The utility of adding radiation to a chemotherapy backbone remains in question. Due to remnant fibrosis and edema following neoadjuvant therapy, accurately selecting patients for resection based on a restaging CT scan is challenging. Furthermore, the role of adjuvant therapy in BR-PDAC patients receiving neoadjuvant therapy needs to be defined.

Conclusion

Though progress has been made, the optimal management of BR-PDAC is uncertain. Phase III trials utilizing modern chemotherapeutic regimens are needed to establish a standard of care.

The connection between innervation and metabolic rearrangements in pancreatic cancer through serine

Pancreatic cancer is a kind of aggressive tumor famous for its lethality and intractability, and pancreatic ductal adenocarcinoma is the most common type. Patients with pancreatic cancer often suffer a rapid loss of weight and abdominal neuropathic pain in their early stages and then go through cachexia in the advanced stage. These features of patients are considered to be related to metabolic reprogramming of pancreatic cancer and abundant nerve innervation responsible for the pain. With increasing literature certifying the relationship between nerves and pancreatic ductal adenocarcinoma (PDAC), more evidence point out that innervation's role is not limited to neuropathic pain but explore its anti/pro-tumor functions in PDAC, especially the neural-metabolic crosstalks. This review aims to unite pancreatic cancer's innervation and metabolic rearrangements with terminated published articles. Hopefully, this article could explore the pathogenesis of PDAC and further promote promising detecting or therapeutic measurements for PDAC according to the lavish innervation in PDAC.

Effects of Berberine against Pancreatitis and Pancreatic Cancer

The pancreas is a glandular organ with endocrine and exocrine functions necessary for the maintenance of blood glucose homeostasis and secretion of digestive enzymes. Pancreatitis is characterized by inflammation of the pancreas leading to temporary or permanent pancreatic dysfunction. Inflammation and fibrosis caused by chronic pancreatitis exacerbate malignant transformation and significantly increase the risk of developing pancreatic cancer, the world's most aggressive cancer with a 5-year survival rate less than 10%. Berberine (BBR) is a naturally occurring plant-derived polyphenol present in a variety of herbal remedies used in traditional medicine to treat ulcers, infections, jaundice, and inflammation. The current review summarizes the existing in vitro and in vivo evidence on the effects of BBR against pancreatitis and pancreatic cancer with a focus on the signalling mechanisms underlying the effects of BBR.

Assessment of stromal SCD-induced drug resistance of PDAC using 3D-printed zPDX model chips

Lipid metabolism is extensively reprogrammed in pancreatic ductal adenocarcinoma (PDAC). Stearoyl-coenzyme A desaturase (SCD) is a critical lipid regulator that was unexplored in PDAC. Here, we characterized the existence of cancer-associated fibroblasts (CAFs) with high SCD expression, and revealed them as an unfavorable prognostic factor. Therefore, primary CAFs and pancreatic cancer cells were harvested and genetically labeled. The mixture of CAFs and cancer cells were co-injected into scd^-/-; prkdc^-/-, or hIGF1/INS-expressing zebrafish to generate patient-derived xenograft models (zPDX). The models were aligned in 3D-printed chips for semi-automatic drug administration and high-throughput scanning. The results showed that chaperoning of the SCD-high CAFs significantly improved the drug resistance of pancreatic cancer cells against gemcitabine and cisplatin, while the administration of SCD inhibitors neutralized the protective effect. Our studies revealed the prognostic and therapeutic value of stromal SCD in PDAC, and proposed the application of zPDX model chips for drug testing.

The novel subclusters based on cancer-associated fibroblast for pancreatic adenocarcinoma

Introduction

Pancreatic adenocarcinoma (PAAD) is a fatal disease characterized by promoting connective tissue proliferation in the stroma. Activated cancer-associated fibroblasts (CAFs) play a key role in fibrogenesis in PAAD. CAF-based tumor typing of PAAD has not been explored.

Methods

We extracted single-cell sequence transcriptomic data from GSE154778 and CRA001160 datasets from Gene Expression Omnibus or Tumor Immune Single-cell Hub to collect CAFs in PAAD. On the basis of Seurat packages and new algorithms in machine learning, CAF-related subtypes and their top genes for PAAD were analyzed and visualized. We used CellChat package to perform cell-cell communication analysis. In addition, we carried out functional enrichment analysis based on clusterProfiler package. Finally, we explored the prognostic and immunotherapeutic value of these CAF-related subtypes for PAAD.

Results

CAFs were divided into five new subclusters (CAF-C0, CAF-C1, CAF-C2, CAF-C3, and CAF-C4) based on their marker genes. The five CAF subclusters exhibited distinct signaling patterns, immune status, metabolism features, and enrichment pathways and validated in the pan-cancer datasets. In addition, we found that both CAF-C2 and CAF-C4 subgroups were negatively correlated with prognosis. With their top genes of each subclusters, the sub-CAF2 had significantly relations to immunotherapy response in the patients with pan-cancer and immunotherapy.

Discussion

We explored the heterogeneity of five subclusters based on CAF in signaling patterns, immune status, metabolism features, enrichment pathways, and prognosis for PAAD.

IGFBP2 Drives Regulatory T Cell Differentiation through STAT3/IDO Signaling Pathway in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) represents one of the deadliest malignancies. Elevated regulatory T cell (Treg) infiltration has a potent immunosuppressive function in tumor biology, which contributes to low survival in PDAC. Nonetheless, the crosstalk between malignant cells and tumor-infiltrating Tregs in PDAC is not well understood. Here, clinical data demonstrates that the insulin-like growth factor binding protein 2 (IGFBP2) is associated with Treg accumulation in the microenvironment of PDAC in humans. Additionally, IGFBP2 increases Treg infiltration in the tumor microenvironment and promotes disease progression in mouse PDAC. Bioinformatic analysis and mechanistic assessment reveals IGFBP2 upregulated indoleamine 2, 3-dioxygenase (IDO) by activating signal transducer and activator of transcription 3 (STAT3) signaling in PDAC cells, thus inducing Treg differentiation and an immunosuppressive tumor microenvironment. These findings provide mechanistic insights into an important molecular pathway that promotes an immunosuppressive microenvironment, which suggests the IGFBP2 axis as a potential target for improved immune response in PDAC.

Circ_0007534 as new emerging target in cancer: Biological functions and molecular interactions

Circular RNA (circRNAs), an important member of the non-coding RNA (ncRNA) family, are widely expressed in a variety of biological cells. Owing to their stable structures, sequence conservations, and cell- or tissue-specific expressions, these RNA have become a popular subject of scientific research. With the development of sequencing methods, it has been revealed that circRNAs exert their biological function by sponging microRNAs (miRNAs), regulating transcription, or binding to proteins. Humans have historically been significantly impacted by various types of cancer. Studies have shown that circRNAs are abnormally expressed in various cancers and are involved in the occurrence and development of malignant tumors, such as tumor cell proliferation, migration, and invasion. As one of its star molecules, circ_0007534 is upregulated in colorectal, cervical, and pancreatic cancers; is closely related to the occurrence, development, and prognosis of tumors; and is expected to become a novel tumor marker and therapeutic target. This article briefly reviews the expression and mechanism of circ_0007534 in malignant tumors based on the domestic and foreign literature.

A comprehensive prognostic and immune infiltration analysis of EXOC3L1 in pan-cancer

Exocyst complex component 3 like 1 (EXOC3L1) is widely present in various human tissues, which mainly regulates insulin secretion. However, its roles in tumors remain unclear. In the present study, we aimed to investigate the roles of EXOC3L1 in pan-cancer, and the data was downloaded from of the University of California Santa Cruz (UCSC) Xena and the Cancer Genome Atlas (TCGA). The expression status of EXOC3L1 was studied in the TCGA_GTEx samples, TCGA samples and paired samples in TCGA, respectively. Subsequently, Kaplan-Meier analysis was applied to 33 kinds of tumors in TCGA, among the cancers that EXOC3L1 can affect prognosis, clinical correlation analysis and univariate Cox regression analysis were performed. Furthermore, representative cancers kidney renal clear cell carcinoma (KIRC) and lung squamous cell carcinoma (LUSC) with a sample size larger than 500 were selected to construct nomogram models to confirm the prognostic value of EXOC3L1 in cancers. Additionally, the associations of EXOC3L1 with immune cell infiltrations were performed as well. Mechanistically, functional enrichment analysis was performed to explore potential signaling pathways that EXOC3L1 may involve in. Our study found that EXOC3L1 was differentially expressed in a variety of tumors and was associated with the clinical outcomes and immune microenvironment of several tumors, it may affect the occurrence and development of tumors through NOTCH signaling pathway, PI3K-AKT signaling pathway and immune-related pathways. In conclusion, we propose that EXOC3L1 may serve as a potential prognostic biomarker and a promising target for cancer immunotherapy in a variety of cancers.

Hyperthermia-induced stellate cell deactivation to enhance dual chemo and pH-responsive photothermal therapy for pancreatic cancers

For pancreatic ductal adenocarcinoma (PDAC) treatment, the deactivation of pancreatic stellate cells (PSCs) by blocking the transforming growth factor β (TGF-β) pathway is a promising strategy to inhibit stroma, enhance drug penetration, and greatly amplify chemotherapeutic efficacy. It is known that photothermal therapy (PTT) locally depletes stroma and enhances permeability but whether and how PTT reacts in the molecular pathway to induce PSC deactivation in PDAC has rarely been investigated so far. Herein, C-G NPs are synthesized by loading both acid-responsive photothermal molecules and gemcitabine for investigating both the combinatory chemophotothermal therapy and the interaction between the PTT and TGF-β pathway in PDAC. Notably, C-G NPs exhibit tumoral acidic pH-activated PTT and succeeded in deactivating PSCs and suppressing the expression level for both TGF-β and collagen fiber. Furthermore, hyperthermia remodels the tumoral extracellular matrix, significantly improves NP penetration, and boosts the ultimate synergistic chemophotothermal therapeutic efficacy. Importantly, the molecular biology study reveals that hyperthermia leads to the decrease in the mRNA expression of TGF-β1, SMAD2, SMAD3, α-SMA, and Collagen I in the tumor tissue, which is the key to suppress tumor progression. This research demonstrates that combinatory chemophotothermal therapy holds great promise for PDAC treatment.

Regulation of pancreatic cancer therapy resistance by chemokines

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy characterized by high resistance and poor response to chemotherapy. In addition, the poorly immunogenic pancreatic tumors constitute an immunosuppressive tumor microenvironment (TME) that render immunotherapy-based approaches ineffective. Understanding the mechanisms of therapy resistance, identifying new targets, and developing effective strategies to overcome resistance can significantly impact the management of PDAC patients. Chemokines are small soluble factors that are significantly deregulated during PDAC pathogenesis, contributing to tumor growth, metastasis, immune cell trafficking, and therapy resistance. Thus far, different chemokine pathways have been explored as therapeutic targets in PDAC, with some promising results in recent clinical trials. Particularly, immunotherapies such as immune check point blockade therapies and CAR-T cell therapies have shown promising results when combined with chemokine targeted therapies. Considering the emerging pathological and clinical significance of chemokines in PDAC, we reviewed major chemokine-regulated pathways leading to therapy resistance and the ongoing endeavors to target chemokine signaling in PDAC. This review discusses the role of chemokines in regulating therapy resistance in PDAC and highlights the continuing efforts to target chemokine-regulated pathways to improve the efficacy of various treatment modalities.

Average treatment effect of facility hepatopancreatobiliary cancer volume on survival of non-resected pancreatic adenocarcinoma

BACKGROUND

To examine the average treatment effect of hepato-pancreato-biliary (HPB) cancer volume on survival outcomes of patients with non-resected pancreatic adenocarcinoma (PDAC).

METHODS

We queried the National Cancer Database (2004-2018) for patients with HPB malignancies (PDAC, pancreatic neuroendocrine neoplasms, hepatocellular carcinoma, biliary tract cancers). We determined the 25th, 50th, and 75th percentiles based on the total annual HPB volume. We then identified patients with non-resected PDAC. We utilized inverse probability (IP)-weighted Cox regression to estimate the effect of facility volume on overall survival (OS).

RESULTS

We identified 710,988 patients with HPB malignancies. The 25th, 50th, and 75th percentiles of total annual HPB volume were 32, 71, and 177 cases/year, respectively. We included a total of 196,150 patients with non-resected PDAC. Patients treated at ≥25th, ≥50th, and ≥75th percentile facilities had improved median OS compared to those treated at facilities below these thresholds (5.8 vs. 4.2months, 6.5 vs. 4.5months, 7.5 vs. 4.8months, respectively; p < 0.001 for all). Treatment at facilities ≥25th, ≥50th, and ≥75th percentile resulted in lower hazards of death than treatment at lower-percentile facilities (HR: 0.87, 95% CI: 0.84-0.90; HR: 0.87, 95% CI: 0.83-0.91; HR: 0.85, 95% CI: 0.79-0.91, respectively).

CONCLUSION

Our data suggest that consolidation of care of patients with PDAC to high-volume centers may be beneficial even in the nonoperative setting.