Clinical significance of the genetic landscape of pancreatic cancer and implications for identification of potential long-term survivors

Fibroblasts in the Aged Pancreas Drive Pancreatic Cancer Progression

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

SIGNIFICANCE

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

Examination of Wnt signaling as a therapeutic target for pancreatic ductal adenocarcinoma (PDAC) using a pancreatic tumor organoid library (PTOL)

Pancreatic ductal adenocarcinoma (PDAC) presents at advanced stages and is refractory to most treatment modalities. Wnt signaling activation plays a critical role in proliferation and chemotherapeutic resistance. Minimal media conditions, growth factor dependency, and Wnt dependency were determined via Wnt inhibition for seven patient derived organoids (PDOs) derived from pancreatic tumor organoid libraries (PTOL). Organoids demonstrating response in vitro were assessed in vivo using patient-derived xenografts. Wnt (in)dependent gene signatures were identified for each organoid. Panc269 demonstrated a trend of reduced organoid growth when treated with ETC-159 in combination with paclitaxel or gemcitabine as compared with chemotherapy or ETC-159 alone. Panc320 demonstrated a more pronounced anti-proliferative effect in the combination of ETC-159 and paclitaxel but not with gemcitabine. Panc269 and Panc320 were implanted into nude mice and treated with ETC-159, paclitaxel, and gemcitabine as single agents and in combination. The combination of ETC-159 and paclitaxel demonstrated an anti-tumor effect greater than ETC-159 alone. Extent of combinatory treatment effect were observed to a lesser extent in the Panc320 xenograft. Wnt (in)dependent gene signatures of Panc269 and 320 were consistent with the phenotypes displayed. Gene expression of several key Wnt genes assessed via RT-PCR demonstrated notable fold change following treatment in vivo. Each pancreatic organoid demonstrated varied niche factor dependencies, providing an avenue for targeted therapy, supported through growth analysis following combinatory treatment of Wnt inhibitor and standard chemotherapy in vitro. The clinical utilization of this combinatory treatment modality in pancreatic cancer PDOs has thus far been supported in our patient-derived xenograft models treated with Wnt inhibitor plus paclitaxel or gemcitabine. Gene expression analysis suggests there are key Wnt genes that contribute to the Wnt (in)dependent phenotypes of pancreatic tumors, providing plausible mechanistic explanation for Wnt (in)dependency and susceptibility or resistance to treatment on the genotypic level.

Synthesis and biological activity of 11-Oxygenated and heterocyclic estrone analogs in pancreatic cancer monolayers and 3D spheroids

Pancreatic Ductal Adenocarcinoma (PDAC), representing over 90 % of pancreatic cancer diagnoses, is an aggressive disease with survivability among the worst of all cancers due to its difficulty in detection and its high metastatic properties. Current therapies for PDAC show limited success at extending life expectancies, primarily due to cancer resistance and lack of patient-specific targeted therapies. This work highlights the design and evaluation of estrone-derived analogs with both heterocyclic side-chain functionality and 11-oxygenated functionality for use in pancreatic cancer. First-round heterocyclic analogs show preliminary promise in AsPC-1 and Panc-1 cell lines, with IC50 values as low as 10.16 ± 0.83 µM. Their success, coupled with design choices from other studies, led to the synthesis of novel 11-hydroxyl and 11-keto estrone analogs that show potent in-vitro toxicity against various pancreatic cancer models. The three most cytotoxic analogs, KA1, KA2, and KA9 demonstrated low micromolar activities in both MTT and CellTiter assays in three pancreatic cancer cell lines: AsPC-1, Panc-1, and BxPC-3, as well as in a co-culture of Panc-1 and pancreatic stellate cells. IC50 values for KA9 (4.17 ± 0.90, 5.28 ± 1.87, and 5.70 ± 0.65 µM respectively) shows consistency in all cell lines tested. KA9 is also able to cause an increase in caspases 3 and 7 activity, key markers for apoptosis, at non-cytotoxic concentrations. Additional work was performed by generating 3D pancreatic cancer spheroids to better modulate the pancreatic tumor microenvironment, and KA9 continued to show the best IC50 values (21.0 and 24.3 µM) in both cell types tested. KA9 was also able to prevent the growth of spheroids whereas the standard chemotherapy, Gemcitabine, could not, suggesting that it may be a potent analog for future development of treatments. Molecular dynamic simulations were also performed to confirm biological findings and uncovered that KA9's preferential binding location is in the active site pocket of key proteins involved in cytotoxicity.

Significance of TP53, CDKN2A, SMAD4 and KRAS in Pancreatic Cancer

The present review demonstrates the major tumor suppressor genes, including TP53, CDKN2A and SMAD4, associated with pancreatic cancer. Each gene's role, prevalence and impact on tumor development and progression are analyzed, focusing on the intricate molecular landscape of pancreatic cancer. In addition, this review underscores the prognostic significance of specific mutations, such as loss of TP53, and explores some potential targeted therapies tailored to these molecular signatures. The findings highlight the importance of genomic analyses for risk assessment, early detection and the design of personalized treatment approaches in pancreatic cancer. Overall, this review provides a comprehensive analysis of the molecular intricacies of pancreatic tumors, paving the way for more effective and tailored therapeutic interventions.

Molecular characteristics of early-onset pancreatic ductal adenocarcinoma

The median age of patients with pancreatic ductal adenocarcinoma (PDAC) at diagnosis is 71 years; however, around 10% present with early-onset pancreatic cancer (EOPC), i.e., before age 50. The molecular mechanisms underlying such an early onset are unknown. We assessed the role of common PDAC drivers (KRAS, TP53, CDKN2A and SMAD4) and determined their mutational status and protein expression in 90 formalin-fixed, paraffin-embedded tissues, including multiple primary and matched metastases, from 37 EOPC patients. KRAS was mutated in 88% of patients; p53 was altered in 94%, and p16 and SMAD4 were lost in 86% and 71% of patients, respectively. Meta-synthesis showed a higher rate of p53 alterations in EOPC than in late-onset PDAC (94% vs. 69%, P = 0.0009) and significantly higher loss of SMAD4 (71% vs. 44%, P = 0.0025). The majority of EOPC patients accumulated aberrations in all four drivers; in addition, high tumour heterogeneity was observed across all tissues. The cumulative effect of an exceptionally high rate of alterations in all common PDAC driver genes combined with high tumour heterogeneity suggests an important mechanism underlying the early onset of PDAC.

Current Advances in the Use of Tissue Engineering for Cancer Metastasis Therapeutics

Cancer is a leading cause of death worldwide and results in nearly 10 million deaths each year. The global economic burden of cancer from 2020 to 2050 is estimated to be USD 25.2 trillion. The spread of cancer to distant organs through metastasis is the leading cause of death due to cancer. However, as of today, there is no cure for metastasis. Tissue engineering is a promising field for regenerative medicine that is likely to be able to provide rehabilitation procedures to patients who have undergone surgeries, such as mastectomy and other reconstructive procedures. Another important use of tissue engineering has emerged recently that involves the development of realistic and robust in vitro models of cancer metastasis, to aid in drug discovery and new metastasis therapeutics, as well as evaluate cancer biology at metastasis. This review covers the current studies in developing tissue-engineered metastasis structures. This article reports recent developments in in vitro models for breast, prostate, colon, and pancreatic cancer. The review also identifies challenges and opportunities in the use of tissue engineering toward new, clinically relevant therapies that aim to reduce the cancer burden.

Mesothelin Secretion by Pancreatic Cancer Cells Co-opts Macrophages and Promotes Metastasis

Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic disease, yet effective treatments to inhibit PDAC metastasis are lacking. The rich PDAC tumor microenvironment plays a major role in disease progression. Macrophages are the most abundant immune cell population in PDAC tumors and can acquire a range of functions that either hinder or promote tumor growth and metastasis. Here, we identified that mesothelin secretion by pancreatic cancer cells co-opts macrophages to support tumor growth and metastasis of cancer cells to the lungs, liver, and lymph nodes. Mechanistically, secretion of high levels of mesothelin by metastatic cancer cells induced the expression of VEGF alpha (VEGFA) and S100A9 in macrophages. Macrophage-derived VEGFA fed back to cancer cells to support tumor growth, and S100A9 increased neutrophil lung infiltration and formation of neutrophil extracellular traps. These results reveal a role for mesothelin in regulating macrophage functions and interaction with neutrophils to support PDAC metastasis.

SIGNIFICANCE

Mesothelin secretion by cancer cells supports pancreatic cancer metastasis by inducing macrophage secretion of VEGFA and S100A9 to support cancer cell proliferation and survival, recruit neutrophils, and stimulate neutrophil extracellular trap formation. See related commentary by Alewine, p. 513.

Expanding the ubiquitin code in pancreatic cancer

The ubiquitin-proteasome system (UPS) is a fundamental regulatory mechanism in cells, vital for maintaining cellular homeostasis, compiling signaling transduction, and determining cell fates. These biological processes require the coordinated signal cascades of UPS members, including ubiquitin ligases, ubiquitin-conjugating enzymes, deubiquitinases, and proteasomes, to ubiquitination and de-ubiquitination on substrates. Recent studies indicate that ubiquitination code rewriting is particularly prominent in pancreatic cancer. High frequency mutation or aberrant hyperexpression of UPS members dysregulates ferroptosis, tumor microenvironment, and metabolic rewiring processes and contribute to tumor growth, metastasis, immune evasion, and acquired drug resistance. We conduct an in-depth overview of ubiquitination process in pancreatic cancer, highlighting the role of ubiquitin code in tumor-promoting and tumor-suppressor pathways. Furthermore, we review current UPS modulators and analyze the potential of UPS modulators as cancer therapy.

Epigenetic control of pancreatic cancer metastasis

Surgical resection, when combined with chemotherapy, has been shown to significantly improve the survival rate of patients with pancreatic ductal adenocarcinoma (PDAC). However, this treatment option is only feasible for a fraction of patients, as more than 50% of cases are diagnosed with metastasis. The multifaceted process of metastasis is still not fully understood, but recent data suggest that transcriptional and epigenetic plasticity play significant roles. Interfering with epigenetic reprogramming can potentially control the adaptive processes responsible for metastatic progression and therapy resistance, thereby enhancing treatment responses and preventing recurrence. This review will focus on the relevance of histone-modifying enzymes in pancreatic cancer, specifically on their impact on the metastatic cascade. Additionally, it will also provide a brief update on the current clinical developments in epigenetic therapies.

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

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

High-Load Gemcitabine Inorganic-Organic Hybrid Nanoparticles as an Image-Guided Tumor-Selective Drug-Delivery System to Treat Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) has a devastating prognosis without effective treatment options. Thus, there is an urgent need for more effective and safe therapies. Here, inorganic-organic hybrid nanoparticles (GMP-IOH-NPs) are presented as a novel drug-delivery system for the selective delivery of extraordinarily high concentrations of gemcitabine monophosphate (GMP), not only to the primary tumor but also to metastatic sites. GMP-IOH-NPs have a composition of [ZrO]2+ [GMP]2 - with GMP as drug anion (76% of total IOH-NP mass). Multiscale fluorescence imaging confirms an efficient uptake in tumor cells, independent of the activity of the human-equilibrative-nucleoside transporter (hENT1), being responsible for gemcitabine (GEM) transport into cells and a key factor for GEM resistance. Delivering already phosphorylated GMP via GMP-IOH-NPs into tumor cells also allows the cellular resistance induced by the downregulation of deoxycytidine kinase to be overcome. GMP-IOH-NPs show high accumulation in tumor lesions and only minor liver trapping when given intraperitoneally. GMP-IOH-NPs result in a higher antitumor efficacy compared to free GEM, which is further enhanced applying cetuximab-functionalized GMP-CTX-IOH-NPs. By maximizing the therapeutic benefits with high drug load, tumor-specific delivery, minimizing undesired side effects, overcoming mechanisms of chemoresistance, and preventing systemic GEM inactivation, GMP-IOH-NPs are anticipated to have a high chance to significantly improve current PDAC-patient outcome.

Post-operative mortality and recurrence patterns in pancreatic cancer according to KRAS mutation and CDKN2A, p53, and SMAD4 expression

Alterations in KRAS, CDKN2A (p16), TP53, and SMAD4 genes have been major drivers of pancreatic carcinogenesis. The clinical course of patients with pancreatic cancer in relation to these driver alterations has not been fully characterised in large populations. We hypothesised that pancreatic carcinomas with different combinations of KRAS mutation and aberrant expression of CDKN2A, p53, and SMAD4 might show distinctive recurrence patterns and post-operative survival outcomes. To test this hypothesis, we utilised a multi-institutional cohort of 1,146 resected pancreatic carcinomas and assessed KRAS mutations by droplet digital polymerase chain reaction and CDKN2A, p53, and SMAD4 expression by immunohistochemistry. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) for disease-free survival (DFS) and overall survival (OS) were computed according to each molecular alteration and the number of altered genes using the Cox regression models. Multivariable competing risks regression analyses were conducted to assess the associations of the number of altered genes with specific patterns of recurrence. Loss of SMAD4 expression was associated with short DFS (multivariable HR, 1.24; 95% CI, 1.09-1.43) and OS times (multivariable HR, 1.27; 95% CI, 1.10-1.46). Compared to cases with 0-2 altered genes, cases with three and four altered genes had multivariable HRs for OS of 1.28 (95% CI, 1.09-1.51) and 1.47 (95% CI, 1.22-1.78), respectively (ptrend  < 0.001). Patients with an increasing number of altered genes were more likely to have short DFS time (ptrend  = 0.003) and to develop liver metastasis (ptrend  = 0.006) rather than recurrence at local or other distant sites. In conclusion, loss of SMAD4 expression and an increasing number of altered genes were associated with unfavourable outcomes in pancreatic cancer patients. This study suggests that the accumulation of the four major driver alterations can confer a high metastatic potential to the liver, thereby impairing post-operative survival among patients with pancreatic cancer.

Microbiome and MicroRNA or Long Non-Coding RNA-Two Modern Approaches to Understanding Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of humans' most common and fatal neoplasms. Nowadays, a number of PDAC studies are being conducted in two different fields: non-coding RNA (especially microRNA and long non-coding RNA) and microbiota. It has been recently discovered that not only does miRNA affect particular bacteria in the gut microbiome that can promote carcinogenesis in the pancreas, but the microbiome also has a visible impact on the miRNA. This suggests that it is possible to use the combined impact of the microbiome and noncoding RNA to suppress the development of PDAC. Nevertheless, insufficient research has focused on bounding both approaches to the diagnosis, treatment, and prevention of pancreatic ductal adenocarcinoma. In this article, we summarize the recent literature on the molecular basis of carcinogenesis in the pancreas, the two-sided impact of particular types of non-coding RNA and the pancreatic cancer microbiome, and possible medical implications of the discovered phenomenon.

Plasma thymidine kinase activity as a prognostic biomarker in pancreatic ductal adenocarcinoma: a single-center prospective study

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) patients might benefit from a biomarker to more precisely prognosticate their overall survival to make more informed treatment and surveillance decisions. The aim of the study was to assess the circulating biomarker Thymidine kinase (TK) activity in samples from patients with PDAC to improve prognostic precision.

MATERIAL AND METHODS

Using the sensitive TK activity (TKa) assay DiviTum®, serum samples from 60 PDAC patients were analyzed.

RESULTS

Median TKa value for patients with PDAC was 931 Du/L. TK activity <931 and CA19-9 < 37 was prognostic for a longer survival, compared to patients with any or both TK activity >931 and CA19-9 > 37, with median 41.3 vs 8.6 months from sample to death (p < 0.001), and 3-year survival was 55.6% vs 8.9% (p < 0.001). Hazard ratio was 2.81 if any or both of TK or CA19-9 were above the cut-off value (p < 0.05).

TKa in combination with CA19-9 outperforms each marker individually for prediction of survival. Overall survival is longer in patients with both TKa <931 Du/L and CA19-9 < 37. Further studies of TKa levels at different disease stages and correlation to outcome is warranted to find the full potential clinical usage of the TKa marker in PDAC.

Expression and role of the immune checkpoint regulator PD-L1 in the tumor-stroma interplay of pancreatic ductal adenocarcinoma

Introduction

Immune checkpoint inhibitors (ICI), e.g., targeting programmed cell death protein 1-ligand 1 (PD-L1) or its receptor PD-1, have markedly improved the therapy of many cancers but so far failed in pancreatic ductal adenocarcinoma (PDAC). Macrophages represent one of the most abundant immune cell populations within the tumor microenvironment (TME) of PDAC being able to either support or restrain tumor progression depending on their phenotype. To better understand treatment failure of PD-L1/PD-1 inhibitors in PDAC, this study examined PD-L1 expression in the context of a dynamic TME in PDAC with a particular focus on the impact of macrophages.

Methods

Formalin-fixed and paraffin embedded tissue samples of primary PDAC tissues and corresponding liver metastases were used for immunohistochemical analyses. Serial sections were stained with antibodies detecting Pan-Cytokeratin, CD68, CD163, CD8, and PD-L1.To investigate whether the PD-1/PD-L1 axis and macrophages contribute to immune escape of PDAC cells, a stroma enriched 3D spheroid coculture model was established in vitro, using different PDAC cell lines and macrophages subtypes as well as CD8+ T cells. Functional and flow cytometry analyses were conducted to characterize cell populations.

Results

Immunohistochemical analyses revealed that PD-L1 is mainly expressed by stroma cells, including macrophages and not PDAC cells in primary PDAC tissues and corresponding liver metastases. Notably, high local abundance of macrophages and strong PD-L1 staining were commonly found at invasion fronts of tumoral lesions between CD8+ T cells and tumor cells. In order to investigate whether PD-L1 expressing macrophages impact the response of PDAC cells to treatment with PD-L1/PD-1 inhibitors, we developed a spheroid model comprising two different PDAC cell lines and different ratios of in vitro differentiated primary M1- or M2-like polarized macrophages. In line with our in situ findings, high PD-L1 expression was observed in macrophages rather than PDAC cells, which was further increased by the presence of PDAC cells. The effector phenotype of co-cultured CD8+ T cells exemplified by expression of activation markers and release of effector molecules was rather enhanced by PDAC macrophage spheroids, particularly with M1-like macrophages compared to mono-culture spheroids. However, this was not associated with enhanced PDAC cell death. ICI treatment with either Durvalumab or Pembrolizumab alone or in combination with Gemcitabine hardly affected the effector phenotype of CD8+ T cells along with PDAC cell death. Thus, despite strong PD-L1 expression in macrophages, ICI treatment did not result in an enhanced activation and cytotoxic phenotype of CD8+ T cells.

Conclusion

Overall, our study revealed novel insights into the interplay of PDAC cells and macrophages in the presence of ICI.

Epigenetic markers and therapeutic targets for metastasis

The last few years have seen an increasing number of discoveries which collectively demonstrate that histone and DNA modifying enzyme modulate different stages of metastasis. Moreover, epigenomic alterations can now be measured at multiple scales of analysis and are detectable in human tumors or liquid biopsies. Malignant cell clones with a proclivity for relapse in certain organs may arise in the primary tumor as a consequence of epigenomic alterations which cause a loss in lineage integrity. These alterations may occur due to genetic aberrations acquired during tumor progression or concomitant to therapeutic response. Moreover, evolution of the stroma can also alter the epigenome of cancer cells. In this review, we highlight current knowledge with a particular emphasis on leveraging chromatin and DNA modifying mechanisms as biomarkers of disseminated disease and as therapeutic targets to treat metastatic cancers.

Insights into the metastatic cascade through research autopsies

Metastasis is a complex process and the leading cause of cancer-related death globally. Recent studies have demonstrated that genomic sequencing data from paired primary and metastatic tumours can be used to trace the evolutionary origins of cells responsible for metastasis. This approach has yielded new insights into the genomic alterations that engender metastatic potential, and the mechanisms by which cancer spreads. Given that the reliability of these approaches is contingent upon how representative the samples are of primary and metastatic tumour heterogeneity, we review insights from studies that have reconstructed the evolution of metastasis within the context of their cohorts and designs. We discuss the role of research autopsies in achieving the comprehensive sampling necessary to advance the current understanding of metastasis.

Circulating Cell-Free Nucleic Acids as Biomarkers for Diagnosis and Prognosis of Pancreatic Cancer

A lack of reliable early diagnostic tools represents a major challenge in the management of pancreatic cancer (PCa), as the disease is often only identified after it reaches an advanced stage. This highlights the urgent need to identify biomarkers that can be used for the early detection, staging, treatment monitoring, and prognosis of PCa. A novel approach called liquid biopsy has emerged in recent years, which is a less- or non-invasive procedure since it focuses on plasmatic biomarkers such as DNA and RNA. In the blood of patients with cancer, circulating tumor cells (CTCs) and cell-free nucleic acids (cfNAs) have been identified such as DNA, mRNA, and non-coding RNA (miRNA and lncRNA). The presence of these molecules encouraged researchers to investigate their potential as biomarkers. In this article, we focused on circulating cfNAs as plasmatic biomarkers of PCa and analyzed their advantages compared to traditional biopsy methods.

Circulating tumor DNA in molecular assessment feasibly predicts early progression of pancreatic cancer that cannot be identified via initial imaging

Molecular assessment using circulating tumor DNA (ctDNA) has not been well-defined. We recruited 61 pancreatic cancer (PC) patients who underwent initial computed tomography (CT) imaging study during first-line chemotherapy. Initial molecular assessment was performed using droplet digital PCR and defined as the change in KRAS-mutated ctDNA before and after treatments, which was classified into five categories: mNT, molecular negative; mCR, complete response; mPR, partial response; mSD, stable disease; mPD, progressive disease. Of 61 patients, 14 diagnosed with PD after initial CT imaging showed significantly worse therapeutic outcomes than 47 patients with disease control. In these 47 patients, initial molecular assessment exhibited significant differences in therapeutic outcomes between patients with and without ctDNA (mPD + mSD vs. mCR + mNT; 13.2 M vs. 21.7 M, P = 0.0029) but no difference between those with mPD and mSD + mCR + mNT, suggesting that the presence of ctDNA had more impact on the therapeutic outcomes than change in its number. Multivariate analysis revealed that it was the only independent prognostic factor (P = 0.0405). The presence of ctDNA in initial molecular assessment predicted early tumor progression and identified PC patients more likely to benefit from chemotherapy.

Integrated analysis of tertiary lymphoid structures in relation to tumor-infiltrating lymphocytes and patient survival in pancreatic ductal adenocarcinoma

BACKGROUND

Tertiary lymphoid structure (TLS) reflects an intense immune response against cancer, which correlates with favorable patient survival. However, the association of TLS with tumor-infiltrating lymphocytes (TILs) and clinical outcomes has not been investigated comprehensively in pancreatic ductal adenocarcinoma (PDAC).

METHODS

We utilized an integrative molecular pathological epidemiology database on 162 cases with resected PDAC, and examined TLS in relation to levels of TILs, patient survival, and treatment response. In whole-section slides, we assessed the formation of TLS and conducted immunohistochemistry for tumor-infiltrating T cells (CD4, CD8, CD45RO, and FOXP3). As confounding factors, we assessed alterations of four main driver genes (KRAS, TP53, CDKN2A [p16], and SMAD4) using next-generation sequencing and immunohistochemistry, and tumor CD274 (PD-L1) expression assessed by immunohistochemistry.

RESULTS

TLSs were found in 112 patients with PDAC (69.1%). TLS was associated with high levels of CD4⁺ TILs (multivariable odds ratio [OR], 3.50; 95% confidence interval [CI] 1.65-7.80; P = 0.0002), CD8⁺ TILs (multivariable OR, 11.0; 95% CI 4.57-29.7, P < 0.0001) and CD45RO⁺ TILs (multivariable OR, 2.65; 95% CI 1.25-5.80, P = 0.01), but not with levels of FOXP3⁺ TILs. TLS was associated with longer pancreatic cancer-specific survival (multivariable hazard ratio, 0.37; 95% CI 0.25-0.56, P < 0.0001) and favorable outcomes of adjuvant S-1-treatment. TLS was not associated with driver gene alterations but tumor CD274 negative expression.

CONCLUSIONS

Our comprehensive data supports the surrogacy of TLS for vigorous anti-tumor immune response characterized by high levels of helper and cytotoxic T cells and their prognostic role.

The role of microRNAs in the modulation of cancer-associated fibroblasts activity during pancreatic cancer pathogenesis

Pancreatic ductal adenocarcinoma (PDAC) is the deadliest of the common cancers. A major hallmark of PDAC is an abundant and dense fibrotic stroma, the result of a disproportionate deposition of extracellular matrix (ECM) proteins. Cancer-associated fibroblasts (CAFs) are the main mediators of PDAC desmoplasia. CAFs represent a heterogenous group of activated fibroblasts with different origins and activation mechanisms. microRNAs (miRNAs) are small non-coding RNAs with critical activity during tumour development and resistance to chemotherapy. Increasing evidence has revealed that miRNAs play a relevant role in the differentiation of normal fibroblasts into CAFs in PDAC. In this review, we discuss recent findings on the role of miRNAs in the activation of CAFs during the progression of PDAC and its response to therapy, as well as the potential role that PDAC-derived exosomal miRNAs may play in the activation of hepatic stellate cells (HSCs) and formation of liver metastasis. Since targeting of CAF activation may be a viable strategy for PDAC therapy, and miRNAs have emerged as potential therapeutic targets, understanding the biology underpinning miRNA-mediated tumour cell-CAF interactions is an important component in guiding rational approaches to treating this deadly disease.

Intraparenchymal metastases as a cause for local recurrence of pancreatic cancer

Using CODA, a technique for three-dimensional reconstruction of large tissues, Kiemen et al. report observation of a microscopic focus of pancreatic cancer found in the vasculature of grossly normal human pancreas tissue resected adjacent to a large tumour. They use TP53 and SMAD4 staining to relate the small focus to the primary tumour. This report describes a represents a probable case of intraparenchymal metastasis of pancreatic cancer, revealing a probable cause of local recurrence.

Molecular features of pancreaticobiliary neoplasms: Implications for diagnosis, prognostication, and therapy selection

BACKGROUND

Molecular diagnostics has impacted the diagnosis, prediction of prognosis, and selection of targeted therapy for many tumor types. While pulmonary adenocarcinomas and melanomas are among the neoplasms most associated with molecular diagnostics and targeted therapy, malignancies of the pancreaticobiliary system have also been impacted by precision medicine.

METHODS

We undertook an electronic search using PubMed and Embase to review the published literature to determine what forms of molecular testing, mutations and oncogenetic pathways are associated with neoplasms of the pancreaticobiliary system. Keywords utilized were pancreas, bile duct, mutations, ERCP, FNA, KRAS, SMAD4, TP53, next-generation sequencing, serous cystadenoma, pancreatic ductal adenocarcinoma, intraductal papillary mucinous neoplasm, cystic mucinous neoplasm, solid pseudo-papillary neoplasm.

RESULTS

A search between 1999 and 2022 yielded 6874 manuscripts. Screening of these yielded 302 more focused manuscripts of which 55 were used for the study. Ductal adenocarcinoma of the pancreas is associated with a progression of mutations beginning wit KRAS mutations and ending with a set of mutations in the TP53, SMAD4, and DPC4 genes. Similar mutations are found in neoplastic mucinous cysts. Specific mutations characterize serous cystadenomas, solid, and pseudo papillary neoplasms and adenocarcinomas of the bile ducts.

CONCLUSIONS

Mutational analysis of cytologic specimens obtained by fine-needle aspiration, and duct brushings and washings are helpful in the diagnosis of pancreaticobiliary neoplasms and may supply prognostic information.

Durable effect of imatinib and metronomic chemotherapy with capecitabine in pancreatic carcinoma

Background

Pancreatic ductal carcinoma (PDC) is a challenging diagnosis with a particularly poor prognosis, even after curative surgery (median survival: <30 months). The prognosis of borderline resectable pancreatic cancer (BR-PDC) is even worse. We describe a patient with BR-PDC who achieved stable disease with metronomic chemotherapy after refusing surgery.

Case presentation

A 75-year-old woman was presented with jaundice and epigastric pain. Imaging confirmed a mass in the pancreatic head encasing the superior mesenteric vein, with obstruction of the pancreatic and bile ducts. After stenting to relieve the obstruction, Fine needle aspiration (FNA) confirmed the diagnosis of PDC. The patient refused surgery and radiation therapy but agreed for chemotherapy. After the second cycle of mFOLFIRINOX - complicated by febrile neutropenia - she refused further IV therapy. Genomic profiling revealed KIT amplification. Therefore, she was started on imatinib with dramatic improvement both clinically and biochemically reflected in carbohydrate antigen 19-9 drop. However, that response was short-lived at 3 months. Therefore, capecitabine was added at a low dose of 1 g bid on an alternate weekly basis. The patient did well and she is currently alive with a stable disease as of 2 years after diagnosis.

Conclusion

Metronomic chemotherapy, especially capecitabine added to the targeted therapy, imatinib, is a potentially useful treatment for PDC where no other options are available, especially those harbouring no mutation in the dominant four genes. Indeed, the absence of mutation with KIT amplification could be a potential marker for improved outcomes with targeted and metronomic therapy, which deserves further evaluation in a clinical trial setting.

Hepatic myofibroblasts exert immunosuppressive effects independent of the immune checkpoint regulator PD-L1 in liver metastasis of pancreatic ductal adenocarcinoma

Introduction

Pancreatic ductal adenocarcinoma (PDAC) represents the 4^th most common cause of cancer-related deaths in Western countries. Most patients are diagnosed at advanced stages, often already with metastases. The main site of metastasis is the liver and hepatic myofibroblasts (HMF) play a pivotal role in metastatic outgrowth. Immune checkpoint inhibitors (ICI) targeting programmed death ligand 1 (PD-L1) or programmed cell death protein 1 (PD-1) improved treatment of several cancers but not of PDAC. Therefore, this study aimed to better understand the impact of HMF on PD-L1 expression and immune evasion of PDAC cells during liver metastasis.

Methods

Formalin-fixed and paraffin embedded biopsy samples or diagnostic resection specimens from liver metastases of 15 PDAC patients were used for immunohistochemical analyses. Serial sections were stained with antibodies directed against Pan-Cytokeratin, αSMA, CD8, and PD-L1. To investigate whether the PD-1/PD-L1 axis and HMF contribute to immune escape of PDAC liver metastases, a stroma enriched 3D spheroid coculture model was established in vitro, using two different PDAC cell lines, HMF, and CD8⁺ T cells. Here, functional and flow cytometry analyses were conducted.

Results

Immunohistochemical analysis of liver tissue sections of PDAC patients revealed that HMF represent an abundant stroma population in liver metastases, with clear differences in the spatial distribution in small (1500 µm) and large (> 1500 μm) metastases. In the latter, PD-L1 expression was mainly located at the invasion front or evenly distributed, while small metastases either lacked PD-L1 expression or showed mostly weak expression in the center. Double stainings revealed that PD-L1 is predominantly expressed by stromal cells, especially HMF. Small liver metastases with no or low PD-L1 expression comprised more CD8⁺ T cells in the tumor center, while large metastases exhibiting stronger PD-L1 expression comprised less CD8⁺ T cells being mostly located at the invasion front. HMF-enriched spheroid cocultures with different ratios of PDAC cells and HMF well mimicking conditions of hepatic metastases in situ. Here, HMF impaired the release of effector molecules by CD8⁺ T cells and the induction of PDAC cell death, an effect that was dependent on the amount of HMF but also of PDAC cells. ICI treatment led to elevated secretion of distinct CD8⁺ T cell effector molecules but did not increase PDAC cell death under either spheroid condition.

Conclusion

Our findings indicate a spatial reorganization of HMF, CD8⁺ T cells, and PD-L1 expression during progression of PDAC liver metastases. Furthermore, HMF potently impair the effector phenotype of CD8⁺ T cells but the PD-L1/PD-1 axis apparently plays a minor role in this scenario suggesting that immune evasion of PDAC liver metastases relies on other immunosuppressive mechanisms.

Loss of tumor suppressor WWOX accelerates pancreatic cancer development through promotion of TGFβ/BMP2 signaling

Pancreatic cancer is one of the most lethal cancers, owing to its late diagnosis and resistance to chemotherapy. The tumor suppressor WW domain-containing oxidoreductase (WWOX), one of the most active fragile sites in the human genome (FRA16D), is commonly altered in pancreatic cancer. However, the direct contribution of WWOX loss to pancreatic cancer development and progression remains largely unknown. Here, we report that combined conditional deletion of Wwox and activation of KRasG12D in Ptf1a-CreER-expressing mice results in accelerated formation of precursor lesions and pancreatic carcinoma. At the molecular level, we found that WWOX physically interacts with SMAD3 and BMP2, which are known activators of the TGF-β signaling pathway. In the absence of WWOX, TGFβ/BMPs signaling was enhanced, leading to increased macrophage infiltration and enhanced cancer stemness. Finally, overexpression of WWOX in patient-derived xenografts led to diminished aggressiveness both in vitro and in vivo. Overall, our findings reveal an essential role of WWOX in pancreatic cancer development and progression and underscore its role as a bona fide tumor suppressor.

Quantitative Analysis of TP53-Related Lung Cancer Based on Radiomics

Background

The role of TP53 mutations in the diagnosis and treatment of lung cancer has attracted increasing attention from experts worldwide. This study aimed to explore the expression of TP53 gene in lung cancer and its correlation with radiomics quantitative features.

Methods

A total of 93 cases of lung cancer confirmed by pathology were selected, including 44 cases with TP53 mutations and 49 cases with TP53 wild-type. ITK-SNAP software was used to segment the pulmonary nodules, AK software was used to extract radiomic features, and a model was established to predict the type of TP53 gene mutation in lung cancer lesions.

Results

A total of 852 features were extracted, and 10 features remained after feature selection. The accuracy, areas under the curve, specificity, sensitivity, positive predictive value, and negative predictive value of the logistic regression model were 0.80, 0.86, 0.89, 0.74, 0.90, and 0.71, respectively.

Conclusion

TP53 gene mutations are correlated with radiomic features in lung cancer, which may have application value for TP53 therapy in the future.

Thrombospondin-1 overexpression stimulates loss of Smad4 and accelerates malignant behavior via TGF-β signal activation in pancreatic ductal adenocarcinoma

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma and cancer-associated fibroblasts (CAFs) provide a favorable tumor microenvironment. Smad4 is known as tumor suppressor in several types of cancers including PDAC, and loss of Smad4 triggers accelerated cell invasiveness and metastatic potential. The thrombospondin-1 (TSP-1) can act as a major activator of latent transforming growth factor-β (TGF-β) in vivo. However, the roles of TSP-1 and the mediator of Smad4 loss and TGF-β signal activation during PDAC progression have not yet been addressed. The aim is to elucidate the biological role of TSP-1 in PDAC progression.

METHODS AND RESULTS

High substrate stiffness stimulated TSP-1 expression in CAFs, and TSP-1 knockdown inhibited cell proliferation with suppressed profibrogenic and activated stroma-related gene expressions in CAFs. Paracrine TSP-1 treatment for PDAC cells promoted cell proliferation and epithelial mesenchymal transition (EMT) with activated TGF-β signals such as phosphorylated Akt and Smad2/3 expressions. Surprisingly, knockdown of DPC4 (Smad4 gene) induced TSP-1 overexpression with TGF-β signal activation in PDAC cells. Interestingly, TSP-1 overexpression also induced downregulation of Smad4 expression and enhanced cell proliferation in vitro and in vivo. Treatment with LSKL peptide, which antagonizes TSP-1-mediated latent TGF-β activation, attenuated cell proliferation, migration and chemoresistance with enhanced apoptosis in PDAC cells.

CONCLUSIONS

TSP-1 derived from CAFs stimulates loss of Smad4 expression in cancer cells and accelerates malignant behavior by TGF-β signal activation in PDAC. TSP-1 could be a novel therapeutic target, not only for CAFs in stiff stroma, but also for cancer cells in the PDAC microenvironment.

Epigenetics in Pancreatic Ductal Adenocarcinoma: Impact on Biology and Utilization in Diagnostics and Treatment

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies with high potential of metastases and therapeutic resistance. Although genetic mutations drive PDAC initiation, they alone do not explain its aggressive nature. Epigenetic mechanisms, including aberrant DNA methylation and histone modifications, significantly contribute to inter- and intratumoral heterogeneity, disease progression and metastasis. Thus, increased understanding of the epigenetic landscape in PDAC could offer new potential biomarkers and tailored therapeutic approaches. In this review, we shed light on the role of epigenetic modifications in PDAC biology and on the potential clinical applications of epigenetic biomarkers in liquid biopsy. In addition, we provide an overview of clinical trials assessing epigenetically targeted treatments alone or in combination with other anticancer therapies to improve outcomes of patients with PDAC.

Personalized pancreatic cancer therapy: from the perspective of mRNA vaccine

Pancreatic cancer is characterized by inter-tumoral and intra-tumoral heterogeneity, especially in genetic alteration and microenvironment. Conventional therapeutic strategies for pancreatic cancer usually suffer resistance, highlighting the necessity for personalized precise treatment. Cancer vaccines have become promising alternatives for pancreatic cancer treatment because of their multifaceted advantages including multiple targeting, minimal nonspecific effects, broad therapeutic window, low toxicity, and induction of persistent immunological memory. Multiple conventional vaccines based on the cells, microorganisms, exosomes, proteins, peptides, or DNA against pancreatic cancer have been developed; however, their overall efficacy remains unsatisfactory. Compared with these vaccine modalities, messager RNA (mRNA)-based vaccines offer technical and conceptional advances in personalized precise treatment, and thus represent a potentially cutting-edge option in novel therapeutic approaches for pancreatic cancer. This review summarizes the current progress on pancreatic cancer vaccines, highlights the superiority of mRNA vaccines over other conventional vaccines, and proposes the viable tactic for designing and applying personalized mRNA vaccines for the precise treatment of pancreatic cancer.

Pharmacologic Targeting of TFIIH Suppresses KRAS-Mutant Pancreatic Ductal Adenocarcinoma and Synergizes with TRAIL

Pancreatic ductal adenocarcinoma (PDAC) typically presents as metastatic disease at diagnosis and remains refractory to treatment. Next-generation sequencing efforts have described the genomic landscape, classified molecular subtypes, and confirmed frequent alterations in major driver genes, with coexistent alterations in KRAS and TP53 correlating with the highest metastatic burden and poorest outcomes. However, translating this information to guide therapy remains a challenge. By integrating genomic analysis with an arrayed RNAi druggable genome screen and drug profiling of a KRAS/TP53 mutant PDAC cell line derived from a patient-derived xenograft (PDCL), we identified numerous targetable vulnerabilities that reveal both known and novel functional aspects of pancreatic cancer biology. A dependence on the general transcription and DNA repair factor TFIIH complex, particularly the XPB subunit and the CAK complex (CDK7/CyclinH/MAT1), was identified and further validated utilizing a panel of genomically subtyped KRAS mutant PDCLs. TFIIH function was inhibited with a covalent inhibitor of CDK7/12/13 (THZ1), a CDK7/CDK9 kinase inhibitor (SNS-032), and a covalent inhibitor of XPB (triptolide), which led to disruption of the protein stability of the RNA polymerase II subunit RPB1. Loss of RPB1 following TFIIH inhibition led to downregulation of key transcriptional effectors of KRAS-mutant signaling and negative regulators of apoptosis, including MCL1, XIAP, and CFLAR, initiating caspase-8 dependent apoptosis. All three drugs exhibited synergy in combination with a multivalent TRAIL, effectively reinforcing mitochondrial-mediated apoptosis. These findings present a novel combination therapy, with direct translational implications for current clinical trials on metastatic pancreatic cancer patients. Significance: This study utilizes functional genetic and pharmacological profiling of KRAS-mutant pancreatic adenocarcinoma to identify therapeutic strategies and finds that TFIIH inhibition synergizes with TRAIL to induce apoptosis in KRAS-driven pancreatic cancer.

Cuproptosis-related gene index: A predictor for pancreatic cancer prognosis, immunotherapy efficacy, and chemosensitivity

Aim

The term "Cuproptosis" was coined to describe a novel type of cell death triggered by intracellular copper buildup that is fundamentally distinct from other recognized types such as autophagy, ferroptosis, and pyroptosis in recent days. As the underlying mechanism was newly identified, its potential connection to pancreatic adenocarcinoma (PAAD) is still an open issue.

Methods

A set of machine learning algorithms was used to develop a Cuproptosis-related gene index (CRGI). Its immunological characteristics were studied by exploring its implications on the expression of the immunological checkpoints, prospective immunotherapy responses, etc. Moreover, the sensitivity to chemotherapeutic drugs was predicted. Unsupervised consensus clustering was performed to more precisely identify different CRGI-based molecular subtypes and investigate the immunotherapy and chemotherapy efficacy. The expression of DLAT, LIPT1 and LIAS were also investigated, through real-time quantitative polymerase chain reaction (RT-qPCR), western blot, and immunofluorescence staining (IFS).

Results

A novel CRGI was identified and validated. Additionally, correlation analysis revealed major changes in tumor immunology across the high- and low-CRGI groups. Through an in-depth study of each medication, it was determined that the predictive chemotherapeutic efficacy of 32 regularly used anticancer drugs differed between high- and low-CRGI groups. The results of the molecular subtyping provided more support for such theories. Expressional assays performed at transcriptomic and proteomic levels suggested that the aforementioned Cuproptosis-related genes might serve as reliable diagnostic biomarkers in PAAD.

Significance

This is, to the best of our knowledge, the first study to examine prognostic prediction in PAAD from the standpoint of Cuproptosis. These findings may benefit future immunotherapy and chemotherapeutic therapies.

Predictors of Long-Term Survival in Pancreatic Ductal Adenocarcinoma after Pancreatectomy: TP53 and SMAD4 Mutation Scoring in Combination with CA19-9

BACKGROUND

Pancreatic ductal adenocarcinoma (PDA) is a fatal cancer for which even unfavorable clinicopathological factors occasionally fail to preclude long-term survival. We sought to establish a scoring system that utilizes measurable pre-intervention factors for predicting survival following surgical resection.

METHODS

We retrospectively analyzed 34 patients who died from short-term recurrences and 32 long-term survivors among 310 consecutively resected patients with PDA. A logistic regression model was used to define factors related to clinical parameters, molecular profiles of 18 pancreatic cancer-associated genes, and aberrant expression of major tumor suppressors.

RESULTS

Carbohydrate antigen 19-9 (CA19-9) had the best ability to classify patients with short-term recurrence and long-term survivors [odds ratio 21.04, 95% confidence interval (CI) 4.612-96.019], followed by SMAD4 and TP53 mutation scoring (odds ratio 41.322, 95% CI 3.156-541.035). Missense TP53 mutations were strongly associated with the nuclear expression of p53, whereas truncating mutations were associated with the absence of nuclear p53. The former subset was associated with a worse prognosis. The combination of aberrant SMAD4 and mutation types of TP53 exhibited a better resolution for distinguishing patients with short-term recurrences from long-term survivors (compared with the assessment of the number of mutated KRAS, CDKN2A, TP53, and SMAD4 genes). Calibration of mutation scores combined with CA19-9 in a logistic regression model setting demonstrated a practical effect in classifying long survivors and patients with early recurrence (c-statistic = 0.876).

CONCLUSIONS

Genetic information, i.e., TP53 mutation types and SMAD4 abnormalities, combined with CA19-9, will be a valuable tool for improving surgical strategies for pancreatic cancer.

Molecular Landscape and Prognostic Biomarker Analysis of Advanced Pancreatic Cancer and Predictors of Treatment Efficacy of AG Chemotherapy

Purpose

Although mutational analysis of pancreatic cancer has provided valuable clinical information, it has not significantly changed treatment prospects. The purpose of this study is to further investigate molecular alterations in locally advanced pancreatic cancer and identify predictors of the efficacy of nab-paclitaxel plus gemcitabine (AG) chemotherapy.

Experimental design

Tumor samples from 118 pancreatic cancer patients who received AG chemotherapy as first-line treatment were sequenced and genomic profile was generated. Molecular alterations and the involved signaling pathways were analyzed. Genes with a significant difference in mutation frequency between primary and metastatic tumors were identified, and prognostic-related mutant genes were screened using SPSS version 22.0.

Results

The most common altered genes in the patients were KRAS (94.9%), TP53 (81.4%), CDKN2A (36.4%), and SMAD4 (22.9%). The mutational frequencies of CDKN2B (14.8% vs. 0%, p = 0.001), FAT3 (7.4% vs. 0%, p = 0.041), MTAP (13% vs. 1.6%, p = 0.023), and SMAD4 (31.4% vs. 15.6%, p = 0.049) in metastatic tumors were significantly higher than that in primary tumors. TP35 and KRAS mutations were significantly correlated with objective response rate, while EPHA7, RNF43, and HMGA2 mutations were significantly correlated with disease control rate. Additionally, patients with TGFR2B, FGF23, EPHA7, SMARCA4, CARD11, ADGRA2, CCNE1, and ACVR2A alterations had a worse overall survival. Further, EPHA7, CARD11, NOTCH1, GATA6, ACVR2A, and HMGA2 mutations indicated undesirable progression-free survival.

Conclusions

CDKN2B, FAT3, MTAP, and SMAD4 may be biomarkers that distinguish primary tumors from metastases. EPHA7 mutation may serve as a prognostic biomarker to predict the treatment efficacy of AG chemotherapy in locally advanced pancreatic cancer.

Two Novel Nomograms Predicting the Risk and Prognosis of Pancreatic Cancer Patients With Lung Metastases: A Population-Based Study

Background

Pancreatic cancer (PC) is one of the most common malignant types of cancer, with the lung being the frequent distant metastatic site. Currently, no population-based studies have been done on the risk and prognosis of pancreatic cancer with lung metastases (PCLM). As a result, we intend to create two novel nomograms to predict the risk and prognosis of PCLM.

Methods

PC patients were selected from the Surveillance, Epidemiology, and End Results Program (SEER) database from 2010 to 2016. A multivariable logistic regression analysis was used to identify risk factors for PCLM at the time of diagnosis. The multivariate Cox regression analysis was carried out to assess PCLM patient's prognostic factors for overall survival (OS). Following that, we used area under curve (AUC), time-dependent receiver operating characteristics (ROC) curves, calibration plots, consistency index (C-index), time-dependent C-index, and decision curve analysis (DCA) to evaluate the effectiveness and accuracy of the two nomograms. Finally, we compared differences in survival outcomes using Kaplan-Meier curves.

Results

A total of 803 (4.22%) out of 19,067 pathologically diagnosed PC patients with complete baseline information screened from SEER database had pulmonary metastasis at diagnosis. A multivariable logistic regression analysis revealed that age, histological subtype, primary site, N staging, surgery, radiotherapy, tumor size, bone metastasis, brain metastasis, and liver metastasis were risk factors for the occurrence of PCLM. According to multivariate Cox regression analysis, age, grade, tumor size, histological subtype, surgery, chemotherapy, liver metastasis, and bone metastasis were independent prognostic factors for PCLM patients' OS. Nomograms were constructed based on these factors to predict 6-, 12-, and 18-months OS of patients with PCLM. AUC, C-index, calibration curves, and DCA revealed that the two novel nomograms had good predictive power.

Conclusion

We developed two reliable predictive models for clinical practice to assist clinicians in developing individualized treatment plans for patients.

Current Pathology Model of Pancreatic Cancer

Pancreatic cancer (PC) is one of the most aggressive and lethal malignant neoplasms, ranking in seventh place in the world in terms of the incidence of death, with overall 5-year survival rates still below 10%. The knowledge about PC pathomechanisms is rapidly expanding. Daily reports reveal new aspects of tumor biology, including its molecular and morphological heterogeneity, explain complicated "cross-talk" that happens between the cancer cells and tumor stroma, or the nature of the PC-associated neural remodeling (PANR). Staying up-to-date is hard and crucial at the same time. In this review, we are focusing on a comprehensive summary of PC aspects that are important in pathologic reporting, impact patients' outcomes, and bring meaningful information for clinicians. Finally, we show promising new trends in diagnostic technologies that might bring a difference in PC early diagnosis.

The identification of liver metastasis- and prognosis-associated genes in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is an often fatal malignancy with an extremely low survival rate. Liver metastasis, which causes high mortality, is the most common recurring metastasis for PDAC. However, the mechanisms underlying this liver metastasis and associated candidate biomarkers are unknown.

METHODS

We performed mRNA profiling comparisons in 8 primary tumors (T) and 12 liver metastases (M) samples using the Gene Expression Omnibus (GEO) database. After determining differentially expressed genes (DEG), gene ontology (GO), pathway enrichment and protein-protein interaction (PPI) network analyses were performed to determine DEG functions. Then, Cytoscape was used to screen out significant hub genes, after which their clinical relevance was investigated using The Cancer Genome Atlas (TCGA) resources. Furthermore, prognosis-associated gene expression was validated using Oncomine and TCGA database. Lastly, associations between prognosis-associated genes, immune cells and immunological checkpoint genes were evaluated using the Tumor Immune Estimation Resource (TIMER).

RESULTS

In total, 102 genes were related to liver metastasis and predominantly involved in cell migration, motility, and adhesion. Using Cytoscape, this number was narrowed down to 16 hub genes. Elevated mRNA expression levels for two of these genes, SPARC (P = 0.019) and TPM1 (P = 0.037) were significantly correlated with poor disease prognosis. For the remaining 14, expression was not related to overall patient survival. SPARC had higher expression in patients with metastatic PDAC than those with non-metastatic PDAC in TCGA dataset. SPARC and TPM1 levels were also positively correlated with the immune infiltration of specific cell types. Additionally, both genes exhibited strong co-expression associations with immune checkpoint genes.

CONCLUSIONS

Combined, we suggest SPARC has high potential as biomarker to predict liver metastasis during PDAC. Additionally, both SPARC and TPM1 appeared to recruit and regulate immune-infiltrating cells during these pathophysiological processes.

Isolated Pancreatic Metastases of Renal Cell Cancer: Genetics and Epigenetics of an Unusual Tumour Entity

Isolated pancreatic metastases of renal cell carcinoma (isPMRCC) are a rare manifestation of metastatic renal cell carcinoma (mRCC) characterized by two peculiarities: (1). The definite or at least long-term exclusive occurrence of metastases in the pancreas and (2). an unusual low tumour aggressiveness with slow tumour progression and consecutive, good treatment results. According to current knowledge, the exclusive occurrence of pancreatic metastases is due to a highly specific and highly selective seed and soil mechanism, which does not allow metastases settlement outside the pancreas, and whose detailed genetic/epigenetic causes are not yet elucidated. Recent studies have shed light on some of the pathways involved for the protracted course of the disease and highlighted a special genetic profile (lack of loss of 9p, lower weight genome instability index, low frequency of BAP1 alterations, and a high frequency of PBRM1 loss), which deviates from the conventional mRCC profile. Finally, the question of the reasons for the long-term relative genetic stability of the involved cell clones, which is an essential prerequisite for a favourable prognosis, remains unanswered.

Genomic alterations drive metastases formation in pancreatic ductal adenocarcinoma cancer: deciphering the role of CDKN2A and CDKN2B in mediating liver tropism

Metastases are often the direct cause of death from pancreatic ductal adenocarcinoma (PDAC). The role of genomic alterations (GA) in mediating tropism and metastasis formation by PDAC cells is currently unknown. We aimed to identify GAs predisposing colonization of PDAC cells to the liver and decipher mechanisms enabling this process. In order to reveal specific genes, we studied the frequency of GA in 8,880 local and 7,983 metastatic PDAC samples. We observed differential pattern of GA in the local tumor and specific metastatic sites, with liver metastases characterized by deletion of CDKN2A/B (encoding p16/p15, respectively). The role of CDKN2A/B in promoting liver metastasis was evidenced by enhanced tumorigenic phenotype of p15/p16-deleted PDAC cells when exposed to hepatocytes conditioned media. The liver is characterized by high-ammonia low-glutamine environment and transcriptomic assays indicated unique adaptation of PDAC cells to these conditions, including regulation of genes leading to reduced glutaminolysis, like overexpression of GLUL and reduction in GLS2. Furthermore, metabolic assays indicated an increase in glutamate derived from [U-13C]-glucose in p15/p16-deleted cells. Importantly, these cells thrived under high ammonia condition. These data suggest a unique role for genomic alterations in mediating tropism of PDAC. Among these alterations, p15/16 deletion was identified as a promoter of liver metastases. Further studies indicated a unique role for p15/16 in regulating glutaminolysis. These findings reveal vulnerabilities in PDAC cells, which may pave the way for the development of novel therapeutic strategies aiming at the prevention of liver metastases formation.

Genetic Alterations Predict Long-Term Survival in Ductal Adenocarcinoma of the Pancreatic Head

Simple Summary

Pancreatic cancer is notorious for its poor prognosis. However, rare long-term survivors of pancreatic cancer exist. The aim of this study was to characterize the molecular profile of pancreatic cancer long-term survivors, to improve the stratification and management of pancreatic cancer patients in the future. Thirty-nine pancreatic cancer patients including short-term and long-term survivors were evaluated thoroughly. Their molecular profile was analyzed using panel next generation sequencing. As a result, patients with mutations commonly found in pancreatic cancer (KRAS G12D mutations and/or TP53 nonsense and splice site mutations) showed significantly worse survival. In contrast, long-term survivors of pancreatic cancer did not show the above-mentioned mutations but did show rare mutations of KRAS (Q61H/D57N). In conclusion, long-term survivors of pancreatic cancer do have a distinct molecular profile. Further studies using larger patient cohorts are warranted to confirm these results and possibly unravel rare potential targets for targeted therapy in pancreatic cancer.

Abstract

Background: Survival of patients with adenocarcinoma of the pancreas (PDAC) is poor and has remained almost unchanged over the past decades. The genomic landscape of PDAC has been characterized in recent years. The aim of this study was to identify a genetic profile as a possible predictor of prolonged survival in order to tailor therapy for PDAC patients. Methods: Panel next generation sequencing (NGS) and immunohistochemistry (IHC) were performed on paraffin-embedded tumor tissues from curatively treated PDAC patients. Tumor slides were re-evaluated with a focus on the histomorphology. Patients were subgrouped according to short and long overall (<4 years/>4 years) and disease-free (<2 years/>2 years) survival. Results: Thirty-nine patients were included in the study. Clinicopathological staging variables as well as the histomorphological subgroups were homogenously distributed between short- and long-term overall and disease-free survivors. In survival analysis, patients with the KRAS G12D mutation and patients with TP53 nonsense and splice-site mutations had a significantly worse overall survival (OS) and disease-free survival (DFS). Patients with long-term OS and DFS showed no KRAS G12D, no TP53 nonsense or splice-site mutations. Rare Q61H/D57N KRAS mutations were only found in long-term survivors. The allele frequency rate of KRAS and TP53 mutations in tumor cells was significantly higher in short-term disease-free survivors and overall survivors, respectively. Conclusions: NGS of PDAC revealed significant differences in survival outcome in a patient collective with homogenously distributed clinicopathological variables. Further multi-institutional studies are warranted to identify more long-term survivors to detect genetic differences suitable for targeted therapy.

Molecular Profiling in Pancreatic Cancer: Current Role and Its Impact on Primary Surgery

Background

The advent of next-generation sequencing technologies has enabled the identification of molecular subtypes of pancreatic ductal adenocarcinoma (PDAC) with different biological traits and clinically targetable features.

Summary

Although current chemotherapy trials are currently exploiting this knowledge, these molecular subtypes have not yet sufficiently caught the attention of surgeons. In fact, integration of these molecular subtypes into the timing of surgery can in theory improve patient outcome. Here, we present the molecular subtypes of PDAC from the surgeon's perspective and a clinically applicable algorithm that integrates the molecular subtyping of PDAC preoperatively into the decision of primary surgery versus neoadjuvant therapy. Furthermore, we point out the potential of "tailored" (in addition to conventional) neoadjuvant treatment for exploiting the molecular subtypes of PDAC.

Key Messages

We believe that for surgeons, the preoperative knowledge on the subtype of PDAC can properly guide in deciding between upfront surgery versus neoadjuvant treatment for improving patient outcome.

Genetic landscape of pancreatic adenocarcinoma patients: a pilot study from Pakistan

BACKGROUND

Pancreatic adenocarcinoma is one of the most aggressive malignancies with extremely low survival rate. Studies have shown that the exploration of key genes can provide a basis for targeted treatment of these patients. The genomic architecture of the Pakistani pancreatic adenocarcinoma patients remains unexplored. Keeping the scenario in place, the current study aims to analyse 88 cancer related genes in Pakistani pancreatic adenocarcinoma patients in order to elucidate candidate gene(s) for targeted molecular therapy.

METHODS AND RESULTS

A total 18 patients were included in the study initially and FFPE tumor samples were obtained. After confirmation of diagnosis and appropriate tumor content, DNA was extracted. Based on the quality and quantity of the extracted DNA, six pancreatic adenocarcinoma tumor samples were selected. Following to this, all the samples were subjected to targeted sequencing (Axen Cancer Panel 1). Variant detection was done and clinical significance of identified variants was assessed using ClinVar database. Targeted sequencing of tumor samples revealed a total of 29 alterations in the coding region of various genes. Among these five pathogenic variants were found in KRAS, BRCA1, TP53 and APC genes.

CONCLUSION

This is the first study that explores genes involved in pancreatic adenocarcinoma from the Pakistani population. Results obtained from the pilot study can guide us about the key genetic players in the Pakistani pancreatic adenocarcinoma population. This can lead to our better understanding of the molecular targeted therapies for these patients and designing future researches on larger sample size.

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.

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

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

Pirfenidone-loaded exosomes derived from pancreatic ductal adenocarcinoma cells alleviate fibrosis of premetastatic niches to inhibit liver metastasis

Pirfenidone delivery systems based on pancreatic cancer cell exosomes precisely reach HSCs and alleviate fibrotic microenvironments, thus inhibiting tumour metastasis.

Development and evaluation of cancer differentiation analysis technology: a novel biophysics-based cancer screening method

BACKGROUND

Routine health checkup is an essential strategy for monitoring population health and maintaining healthy workforces. However, there was a lack of cancer screening tests among routine health checkups due to high costs and unreliable methods.

METHODS

We conducted a two-stage study to evaluate the value of a blood test, Cancer Differentiation Analysis (CDA^TM), which is developed to differentiate the blood samples of healthy individuals from those of cancer patients through measuring and analyzing multiple biophysical properties.

RESULTS

The first stage of a cross-sectional study included 75,942 healthy individuals in routine health checkup, and the second stage of a prospective population-based cohort included 1,957 healthy community members. Forty-eight and ten cancer cases were identified among cross-sectional study and prospective population-based cohort, respectively. Using a pre-determined cutoff, we found that the CDA™ test could differentiate blood samples between healthy and cancer individuals with >93% specificity and >55% sensitivity in both studies.

CONCLUSIONS

With high specificity and moderate sensitivity of CDA™ test, our study indicates that we can analyze biophysical properties in the blood to rapidly and reliably screen healthy individuals from cancer patients in a health checkup setting where most individuals are healthy or with average risk of cancer.

Evolving pancreatic cancer treatment: From diagnosis to healthcare management

The prognosis of pancreatic ductal adenocarcinoma is still the worst among solid tumors. In this review, a panel of experts addressed the main unanswered questions about the clinical management of this disease, with the aim of providing practical decision support for physicians. On the basis of the evidence available from the literature, the main topics concerning pancreatic cancer are discussed: the diagnosis, as the need for a pathological characterization and the role for germ-line and somatic molecular profiling; the therapeutic management of resectable disease, as the role of upfront surgery or neoadjuvant chemotherapy, the post-operative restaging and the optimal timing foradjuvant chemotherapy, the management of the borderline resectable and locally advanced disease; the metastatic disease and the role of surgery for the management of patients with isolated metastasis and the use of biomarkers of metastatic potential; the role of supportive care and the healthcare management of pancreatic ductal adenocarcinoma.

Individualized prognostic signature for pancreatic carcinoma validated by integrating immune-related gene pairs (IRGPs)

Increasingly attention is being given to immune molecules in pancreatic cancer. The purpose of this study was to understand the potential clinical application of immune-regulated genes (IRGs) in the stratification of prognosis and to facilitate the development of personalized prognostic information for pancreatic cancer patients. We systematically used public data to comprehensively analyze immune-regulated gene pair (IRGP) expression profiles and clinical data. In our study, IRGP signature was identified to predict the overall survival (OS) of pancreatic cancer patients. We suggested that immune genes are enriched in different risk groups. In the high-risk group, M1 macrophages and resting NK cells were significantly enriched, while the percentages of naïve B cells, resting dendritic cells, CD8 T cells and regulatory T cells (Tregs) were significantly higher in the low-risk group, and we verified these results with immunohistochemical experiments. Gene ontology (GO) analysis confirmed that the IRGP index (IRGPI) signature genes in the cohort were mostly party to sensory perception of a chemical stimulus and the adaptive immune response. The identification of these pathways provides a basis for studying the molecular mechanisms of IRGPI signaling to predict the prognosis of pancreatic cancer. Our study effectively constructed a robust IRGP signature with prognostic value for pancreatic cancer, presenting a conceivable method for deciding on a preoperative treatment.

PEPT1 is essential for the growth of pancreatic cancer cells: a viable drug target

PEPT1 is a proton-coupled peptide transporter that is up-regulated in PDAC cell lines and PDXs, with little expression in the normal pancreas. However, the relevance of this up-regulation to cancer progression and the mechanism of up-regulation have not been investigated. Herein, we show that PEPT1 is not just up-regulated in a large panel of PDAC cell lines and PDXs but is also functional and transport-competent. PEPT2, another proton-coupled peptide transporter, is also overexpressed in PDAC cell lines and PDXs, but is not functional due to its intracellular localization. Using glibenclamide as a pharmacological inhibitor of PEPT1, we demonstrate in cell lines in vitro and mouse xenografts in vivo that inhibition of PEPT1 reduces the proliferation of the cancer cells. These findings are supported by genetic knockdown of PEPT1 with shRNA, wherein the absence of the transporter significantly attenuates the growth of cancer cells, both in vitro and in vivo, suggesting that PEPT1 is critical for the survival of cancer cells. We also establish that the tumor-derived lactic acid (Warburg effect) in the tumor microenvironment supports the transport function of PEPT1 in the maintenance of amino acid nutrition in cancer cells by inducing MMPs and DPPIV to generate peptide substrates for PEPT1 and by generating a H+ gradient across the plasma membrane to energize PEPT1. Taken collectively, these studies demonstrate a functional link between PEPT1 and extracellular protein breakdown in the tumor microenvironment as a key determinant of pancreatic cancer growth, thus identifying PEPT1 as a potential therapeutic target for PDAC.