Hacking Pancreatic Cancer: Present and Future of Personalized Medicine

Development of a prognostic model based on four genes related to exhausted CD8+ T cell in triple-negative breast cancer patients: a comprehensive analysis integrating scRNA-seq and bulk RNA-seq

Low immune infiltration is closely associated with poor clinical results and an unfavorable response to therapy in triple-negative breast cancer (TNBC). T-cell exhaustion (TEX) is a significant risk factor for tumor immunosuppression and invasion. Although improving TEX and enhancing effector function are promising strategies for strengthening immunotherapy, their role in the pathogenesis of TNBC remains unclear. This study's objective was to develop a prognostic model for TNBC based on exhausted CD8+ T-cell (CD8+ Tex)-related differentially expressed genes (DEGs) and to investigate its clinical and immune relevance. Initially, 398 CD8+ Tex-related genes were screened utilizing single-cell RNA sequencing (scRNA-seq) data from TNBC patients. Pseudotime analysis confirmed that CD8+ Tex mainly clustered at the end of the differentiation pathways, making them a critical subset in TNBC progression. By analyzing the TCGA cohort, ten CD8+ Tex-related DEGs were identified as significantly correlated with overall survival (OS) in TNBC patients, and a prognostic model containing four biomarkers (GBP1, CTSD, ABHD14B, and HLA-A) was constructed. The model demonstrated robust predictive capability in both the TCGA cohort and an external cohort, with the low-risk group exhibiting elevated expression of immunological checkpoint molecules and immune cell infiltration, as well as better responses to immunotherapy and chemotherapy. Furthermore, these four biomarkers were found to be highly expressed on CD8+ Tex and were associated with cellular communication efficiency. Therefore, this model is expected to be a new method for forecasting TNBC patients' prognosis and effectiveness of treatment, providing new insights for clinical decision-making.

Proteogenomic analysis reveals Arp 2/3 complex as a common molecular mechanism in high risk pancreatic cysts and pancreatic cancer

Pancreatic cysts, particularly intraductal papillary mucinous neoplasms (IPMNs), pose a potential risk for progressing to pancreatic cancer (PC). This study investigates the genetic architecture of benign pancreatic cysts and its potential connection to PC using genome-wide association studies (GWAS). The discovery GWAS identified significant genetic variants associated with benign cysts, specifically the rs142409042 variant near the OPCML gene. A pairwise GWAS comparing PC to benign cysts revealed the rs7190458 variant near the BCAR1 and CTRB1 genes. Further analysis with identified GWAS genes highlighted the Actin Related Protein (Arp) 2/3 complex as a potentially important molecular mechanism connecting benign cysts and PC. The Arp2/3 complex-associated genes were significantly upregulated in PC, suggesting their role in the malignant transformation of pancreatic cysts. Differential expression of these genes was observed across various cell types in PC, indicating their involvement in the tumor microenvironment. These findings suggest that the Arp2/3 complex-associated genes can serve as potential biomarkers for predicting the malignant transformation of pancreatic cysts, opening new avenues for targeted therapies and early detection strategies.

Incidence and risk of endocrine and metabolic abnormalities linked to PARP inhibitors in solid tumors: a meta-analysis

BACKGROUND

Poly (ADP-ribose) polymerase inhibitors (PARPi) serve as crucial therapeutic agents in solid tumor treatment. Preclinical investigations suggest a potential protective function of PARPi against endocrine and metabolic impairments. Nevertheless, the existing body of evidence remains inconclusive on this aspect.

PURPOSE

Our aim was to evaluate the potential impact of PARPi on endocrine and metabolic disruptions in clinical trials.

DATA SOURCES

We conducted a comprehensive search across the Medline, EMBASE, PubMed, and Web of Science databases, along with the ClinicalTrials.gov registry.

STUDY SELECTION

Phase II/III randomized controlled trials (RCTs) investigating the effects of PARPi in metabolic and endocrine processes were selected for inclusion in patients with solid tumors.

DATA EXTRACTION

The primary outcomes of interest encompassed metabolic and endocrine dysfunctions.

DATA SYNTHESIS

A total of 26 trials (n = 9,590 patients) were included in our meta-analysis. Niraparib demonstrated an increased risk of any-grade hyperglycemia (OR = 2.15, 95% CI 1.28-3.62), with patients receiving PARPi for metastatic pancreatic cancer showing a higher susceptibility to any-grade hyperglycemia (OR = 1.78, 95% CI 1.04-3.04). Conversely, rucaparib exhibited a potential ameliorative effect on hyperglycemia (OR = 0.54, 95% CI 0.30-0.97). No statistically significant disparities were observed for other outcomes associated with PARPi utilization.

LIMITATIONS

Among these RCTs included, 50% were assessed as low qualities due to high risk of bias.

CONCLUSIONS

Our meta-analysis demonstrated that PARPi may exert adverse effects on endocrine and metabolic pathways. Close monitoring of hyperglycemia is recommended for patients undergoing niraparib therapy, especially those with pancreatic cancer.

TRIAL REGISTRATION

This meta-Analysis was prospectively registered in the PROSPERO database with ID CRD42023457959.

Role of mast cell in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy

The pro-tumor effects of mast cell (MC) in the tumor microenvironment (TME) are becoming increasingly clear. Recently, MC were shown to contribute to tumor malignancy by supporting the migration of tumor-associated macrophages (TAMs), suggesting a relationship with tumor immunity. In the current study, we aimed to examine the correlation between MC infiltration and neoadjuvant chemoradiotherapy (nCRT) response for locally advanced rectal cancer (LARC). Ninety-five LARC patients who recieved nCRT were enrolled in this study. Protein levels of the MC marker tryptase and TAM marker CD206 were evaluated with immunohistochemistry (IHC). The correlation between MC infiltration and prognostic factors was evaluated. The effects of MCs on the malignant potential were examined using in vitro proliferation and invasion assays with a colorectal cancer (CRC) cell line (HCT-116). Following nCRT, 31.6% of resected LARC patient specimens were positive for MC infiltration by tryptase IHC analysis. MC infiltration was significantly correlated with nCRT response. The 5-year disease-free survival (DFS) rate was significantly lower in the MC-positive group compared with the MC-negative group (52.3% vs. 76.8%). Univariate and multivariate analyses revealed that MC infiltration was the independent prognostic indicator for DFS. MC infiltration was significantly correlated with CD206 expression, and therefore TAMs. In vitro experiments suggested that tumor activated mast cells could promote CRC cell malignant behavior via production of macrophage inhibitory factor. MC infiltration in LARC patients was positively correlated with TAM infiltration and resistance to nCRT, and was also an independent poor prognostic indicator.

Application of imaging technology for the diagnosis of malignancy in the pancreaticobiliary duodenal junction (Review)

The pancreaticobiliary duodenal junction (PBDJ) is the connecting area of the pancreatic duct, bile duct and duodenum. In a broad sense, it refers to a region formed by the head of the pancreas, the pancreatic segment of the common bile duct and the intraduodenal segment, the descending and the horizontal part of the duodenum, and the soft tissue around the pancreatic head. In a narrow sense, it refers to the anatomical Vater ampulla. Due to its complex and variable anatomical features, and the diversity of pathological changes, it is challenging to make an early diagnosis of malignancy at the PBDJ and define the histological type. The unique anatomical structure of this area may be the basis for the occurrence of malignant tumors. Therefore, understanding and subclassifying the anatomical configuration of the PBDJ is of great significance for the prevention and treatment of malignant tumors at their source. The present review comprehensively discusses commonly used imaging techniques and other new technologies for diagnosing malignancy at the PBDJ, offering evidence for physicians and patients to select appropriate examination methods.

Upregulation of HSD11B1 promotes cortisol production and inhibits NK cell activation in pancreatic adenocarcinoma

Cortisol is a glucocorticoid hormone that has immunosuppressive function. Elevated basal cortisol levels are present in patients with some kinds of cancers, but its role in the microenvironment of pancreatic adenocarcinoma (PAAD) remains unclear. This study analyzed the expression of genes involved in cortisol generation by using high-throughput sequencing data from TCGA portal and found HSD11B1 was significantly upregulated in patients with PAAD. The correlations between HSD11B1 level and the expression of 23 immunosuppressive receptors were analyzed by Spearman's correlation analysis. The function of HSD11B1 was examined in primary NK cells and PAAD cell lines. The levels of cortisol in medium and cell lysates were detected by ELISA. In vitro killing assay was used to evaluate the cytotoxicity of NK cells. Cell surface levels of CD96, Tim-3, PD-1, TIGIT, CTLA-4, NKp46, NKp30, NKD2G and LFA-1A, and intracellular levels of CD107a and IFN-γ were examined by flow cytometry. We observed that patients with higher HSD11B1 level had shorter survival time. HSD11B1 is positively correlated with the mRNA levels of 11 immunosuppressive receptors in PAAD. Higher HSD11B1 level relates to reduced abundance of activated NK cells in the tumors. HSD11B1 overexpressed NK cells exhibit exhausted phenotype with increased cortisol production, reduced viability, and reduced cytotoxicity against cancer cells. Overexpression of HSD11B1 did not change the viability of tumor cells but upregulated cortisol production. Targeting HSD11B1 by a specific inhibitor improved the NK cells responsiveness. In conclusion, HSD11B1 is upregulated in patients with PAAD, and higher HSD11B1 level is related to poor prognosis. Upregulation of HSD11B1 in NK and tumor cells increased the production and secretion of cortisol and induces NK cell exhaustion.

First reported advanced pancreatic cancer with hyperprogression treated with PD-1 blockade combined with chemotherapy: a case report and literature review

Pancreatic cancer is among the most immune-resistant tumor types due to its unique tumor microenvironment and low cancer immunogenicity. Single-agent immune modulators have thus far proven clinically ineffective. However, a growing body of evidence suggests that combination of these modulators with other strategies could unlock the potential of immunotherapy in pancreatic cancer. Herein, we describe the case of a 59-year-old male with metastatic pancreatic ductal adenocarcinoma, referred to our center to receive immunotherapy (serplulimab, a novel anti-PD-1 antibody) combined with chemotherapy (gemcitabine/nab-paclitaxel). During the initial three treatment cycles, the patient was assessed as having stable disease (SD) according to RECIST 1.1 criteria. However, following two additional cycles of combination therapy, the primary tumor mass increased from 4.9 cm to 13.2 cm, accompanied by the development of new lung lesions, ascites, and pelvic metastases. He succumbed to respiratory failure one month later. Retrospective analysis revealed that the patient had MDM4 amplification, identified as a high-risk factor for hyperprogressive disease (HPD). To our knowledge, this is the first reported case of HPD in pancreatic cancer with multiple metastases treated using combination therapy. We investigated the potential mechanisms and reviewed the latest literature on predictive factors for HPD. These findings suggest that while chemotherapy combined with immunotherapy may hold promise for treating pancreatic cancer, it is imperative to identify and closely monitor patients with high-risk factors for HPD when using immunotherapy.

System analysis based on T-cell exhaustion-related genes identifies PTPRT as a promising diagnostic and prognostic biomarker for gastric cancer

Multiple investigations have demonstrated the crucial involvement of T-cell exhaustion (TEX) in anti-tumor immune response and their strong correlation with prognosis. This study aimed at creating a strong signature using TEX for gastric cancer through bioinformatics analysis and experimental validation. We utilized data from The Cancer Genome Atlas (TCGA) databases to retrieve RNA-seq data from patients with stomach adenocarcinoma (STAD). Genes related to TEX were discovered using gene set variance analysis (GSVA) and weighted gene correlation network analysis (WGCNA). Subsequently, prognostic signature based on TEX was developed using LASSO-Cox analysis. Relationship between key genes and immune cells were examined. Finally, biological function of a key TEX-related gene PTPRT in gastric cancer was verified by in vivo experiment. A total of 29 TEX-related biomarkers were screened by WGCNA and random forest. Among them, five core signatures (PTPRT, CAV2, PPIH, PRDM2, and FGF1), further identified by LASSO-Cox, were considered as strong predictors of prognosis for gastric cancer and associated with immune infiltration. PTPRT gene had the largest number of SNPs, with the most mutation types. In vivo experiments revealed that PTPRT overexpression significantly inhibited tumor malignant progression and accelerated apoptosis through stimulating the secretion of killer cytokines such as TNF-α and IFN-γ. In addition, flow cytometry revealed that PTPRT overexpression alleviated TEX by increasing the abundance of CD8+ T cells, with inhibition of cell surface PD-1 and Tim-3. The predictive prognostic value of TEX gene expression levels was evaluated in patients with gastric cancer, providing a new perspective for precision immuno-oncology studies.

Establishment of a prognostic model for pancreatic cancer based on mitochondrial metabolism related genes

AIM

Pancreatic ductal adenocarcinoma (PAAD) is recognized as an exceptionally aggressive cancer that both highly lethal and unfavorable prognosis. The mitochondrial metabolism pathway is intimately involved in oncogenesis and tumor progression, however, much remains unknown in this area. In this study, the bioinformatic tools have been used to construct a prognostic model with mitochondrial metabolism-related genes (MMRGs) to evaluate the survival, immune status, mutation profile, and drug sensitivity of PAAD patients.

METHOD

Univariate Cox regression and LASSO regression were used to screen the differentially expressed genes (DEGs), and multivariate Cox regression was used to develop the risk model. Kaplan-Meier estimator was employed to identify MMRGs signatures associated with overall survival (OS). ROC curves were utilized to evaluate the model's performance. Maftools, immunedeconv and CIBERSORT R packages were applied to analyze the gene mutation profiles and immune status. The corresponding sensitivity to pharmaceutical agents was assessed using oncoPredict R packages.

RESULTS

A prognostic model with five MMRGs was developed, which defined the patients as high-risk showed lower survival rates. There was good consistency among individuals categorized as high-risk, showing elevated rates of genetic alterations, particularly in the TP53 and KRAS genes. Furthermore, these patients exhibited increased levels of immunosuppression, characterized by an increased presence of macrophages, neutrophils, Th2 cells, and regulatory T cells. Additionally, high-risk patients showed increased sensitivity to Sabutoclax and Venetoclax.

CONCLUSION

By utilizing a gene signature associated with mitochondrial metabolism, a prognostic model has been established which could be a highly efficient method for predicting the outcomes of PAAD patients.

Programmed cell death 1 inhibitor sintilimab plus concurrent chemoradiotherapy for locally advanced pancreatic adenocarcinoma

BACKGROUND

Pancreatic adenocarcinoma, a malignancy that arises in the cells of the pancreas, is a devastating disease with unclear etiology and often poor prognosis. Locally advanced pancreatic cancer, a stage where the tumor has grown significantly but has not yet spread to distant organs, presents unique challenges in treatment. This article aims to discuss the current strategies, challenges, and future directions in the management of locally advanced pancreatic adenocarcinoma (LAPC).

AIM

To investigate the feasibility and efficacy of programmed cell death 1 (PD-1) inhibitor sintilimab plus concurrent chemoradiotherapy for LAPC.

METHODS

Eligible patients had LAPC, an Eastern cooperative oncology group performance status of 0 or 1, adequate organ and marrow functions, and no prior anticancer therapy. In the observation group, participants received intravenous sintilimab 200 mg once every 3 wk, and received concurrent chemoradiotherapy (concurrent conventional fractionated radiotherapy with doses planning target volume 50.4 Gy and gross tumor volume 60 Gy in 28 fractions and oral S-1 40 mg/m2 twice daily on days 1-14 of a 21-d cycle and intravenous gemcitabine 1000 mg/m2 on days 1 and 8 of a 21-d cycle for eight cycles until disease progression, death, or unacceptable toxicity). In the control group, participants only received concurrent chemoradiotherapy. From April 2020 to November 2021, 64 participants were finally enrolled with 34 in the observation group and 30 in the control group.

RESULTS

Thirty-four patients completed the scheduled course of chemoradiotherapy, while 32 (94.1%) received sintilimab plus concurrent chemoradiotherapy with 2 patients discontinuing sintilimab in the observation group. Thirty patients completed the scheduled course of chemoradiotherapy in the control group. Based on the Response Evaluation Criteria in Solid Tumors guidelines, the analysis of the observation group revealed that a partial response was observed in 11 patients (32.4%), stable disease was evident in 19 patients (55.9%), and 4 patients (11.8%) experienced progressive disease; a partial response was observed in 6 (20.0%) patients, stable disease in 18 (60%), and progressive disease in 6 (20%) in the control group. The major toxic effects were leukopenia and nausea. The incidence of severe adverse events (AEs) (grade 3 or 4) was 26.5% (9/34) in the observation group and 23.3% (7/30) in the control group. There were no treatment-related deaths. The observation group demonstrated a significantly longer median overall survival (22.1 mo compared to 15.8 mo) (P < 0.05) and progression-free survival (12.2 mo vs 10.1 mo) (P < 0.05) in comparison to the control group. The occurrence of severe AEs did not exhibit a statistically significant difference between the observation group and the control group (P > 0.05).

CONCLUSION

Sintilimab plus concurrent chemoradiotherapy was effective and safe for LAPC patients, and warrants further investigation.

CCR7 affects the tumor microenvironment by regulating the activation of naïve CD8+ T cells to promote the proliferation of oral squamous cell carcinoma

BACKGROUND

Head and neck cancer is the sixth most common malignancy worldwide, and oral squamous cell carcinoma (OSCC) is the most common head and neck cancer, being one of the leading causes of cancer morbidity and mortality worldwide. CC Chemokine receptor 7(CCR7) is a multifunctional G protein-coupled trans-membrane chemokine that affects immune cell chemotaxis, migration, and cancer progression through its interaction with its ligands C-C motif chemokine ligand 19(CCL19) and C-C motif chemokine ligand 21(CCL21). Numerous studies have demonstrated the involvement of CCR7 in the malignant progression of a variety of cancers, reflecting the pro-cancer properties of CCR7. The Cancer Genome Atlas data suggests CCR7 has elevated expression in oral cancer. Specifically, CCR7 expression in tumor microenvironment (TME) may regulate the ability of some immune cells to engage in anti-tumor immune responses. Since CD8+ T cells have become a key immunotherapeutic target, the role of CCR7 in antitumor immune response of naïve CD8+ T cells in TME has not been thoroughly investigated.

METHODS

A CCR7 knockout mouse model was constructed, and the mechanism of ccr7 on the regulation of tumor microenvironment by naïve CD8+ T cells was verified under the guidance of single-cell RNA sequencing combined with in vivo animal experiments and in vitro cell experiments.

RESULTS

CCR7 is knocked out with impaired tumor growth and altered CD8+ T cell profiles, revealing the importance of this protein in OSCC.

CONCLUSIONS

Inhibition of CCR7 enhances CD8+ T cell activation, proliferation, and anti-tumor function, suggesting its potential as a therapeutic target.

Treatment of pancreatic adenocarcinoma in relation to survival in the U.S. Military Health System

BACKGROUND

Pancreatic cancer has a high case fatality and relatively short survival after diagnosis. Treatment is paramount to improving survival, but studies on the effects of standard treatment by surgery or chemotherapy on survival in U.S. healthcare settings is limited. Further, variability in access to care may impact treatment and outcomes for patients. We aimed to assess the relationship between standard treatment(s) and survival of pancreatic adenocarcinoma in a population with access to comprehensive healthcare.

METHODS

We used the Military Cancer Epidemiology (MilCanEpi) database, which includes data from the Department of Defense cancer registry and medical encounter data from the Military Health System (MHS), to study a cohort of 1408 men and women who were diagnosed with pancreatic adenocarcinoma between 1998 and 2014. Treatment with surgery or chemotherapy in relation to overall survival was examined in multivariable time-dependent Cox regression models.

RESULTS

Overall, 75 % of 441 patients with early-stage and 51 % of 967 patients with late-stage pancreatic adenocarcinoma received treatment. In early-stage disease, surgery alone or surgery with chemotherapy were both associated with statistically significant 52 % reduced risks of death, but chemotherapy alone was not. In late-stage disease, surgery alone, chemotherapy alone, or both surgery and chemotherapy significantly reduced the risk of death by 42 %, 25 %, and 52 %, respectively.

CONCLUSIONS

Our findings from the MHS demonstrate improved survival after treatment with surgery or surgery with chemotherapy for early- or late-stage pancreatic cancer and after chemotherapy for late-stage pancreatic cancer. In the era of immunotherapy and personalized medicine, further research on treatment and survival of pancreatic cancer in observational settings is needed.

Long non-coding RNA MIR600HG as a ceRNA inhibits the pancreatic cancer progression through regulating the miR-1197/PITPNM3 axis

Objective

Pancreatic cancer (PC) is considered to be a highly malignant cancer with poor prognosis. Long non-coding RNAs (lncRNAs) is the potential factor to predict cancer prognosis. The effect of MIR600HG in PC needs to be further studied. Our work mainly focused on the importance of MIR600HG for PC prognosis and its underlying molecular mechanism of regulating PC progression.

Methods

Data set was acquired from TCGA database to find differentially expressed genes and prognostic significance of MIR600HG in PC, and to construct the MIR600HG competitive endogenous RNA (ceRNA). Clinical specimens were collected to prove the analysis results. Vector over-expressed MIR600HG was transfected to study the roles of MIR600HG in proliferation, apoptosis, invasion and migration. The methods of CCK-8, flow cytometry, Transwell and scratch assays were all used in order to explore the apoptosis, migration and invasion. We evaluated the proliferation-related genes (PCNA, CyclinD1 and P27), as well as invasion and migration-related genes such as MMP-9, MMP-7 and ICAM-1. The transcriptional regulation between MIR600HG and miR-1197/PITPNM3 axis was determined with luciferase reporter assays.

Results

In present study, MIR600HG was dropped in both PC tissues and cells, and the down-regulated MIR600HG was closely related to the poor clinical outcomes in PC patients. MIR600HG could inhibit proliferation, migration and invasion in PC cells. We also investigated whether MIR600HG acting as a sponge of microRNA-1197 (miR-1197) and miR-1197 acting on PITPNM3. We found the positive association between MIR600HG and PITPNM3, as well as the negative association of miR-1197 and MIR600HG (or PITPNM3). Moreover, PITPNM3 mRNA and protein expression saw a simultaneous increase after the MIR600HG-overexpression (MIR600HG-OE), but this result partially diminished in MIR600HG-OE cells and miR-1197 mimics.

Conclusions

Our study explored the anticancer action of MIR600HG in PC by regulating miR-1197 to increase the expression of PITPNM3, which might help the diagnosis and therapy of PC.

Pancreatic Adenocarcinoma with Co-Occurrence of KRAS and EGFR Mutations: Case Report and Literature Review

Introduction

Mutation in Kristin ras sarcoma virus (KRAS) oncogene is the main driver in pancreatic ductal adenocarcinoma (PDAC) and is present in nearly 90% of patients with PDAC. Epidermal growth factor receptor (EGFR) mutation is rare in PDAC and is mostly present in the absence of KRAS mutation. Co-occurrence of KRAS and EGFR mutations is extremely rare, and the value of EGFR inhibition in these cases is unknown.

Case Presentation

Here, we present a case of metastatic PDAC with co-occurrence of KRAS G12V and EGFR L730R. Despite primary resistance to folinic acid, fluorouracil, irinotecan, oxaliplatin, and gemcitabine/nab-paclitaxel, this patient had a biochemical response (decrease in carbohydrate antigen 19-9) and disease control of 7 months on gemcitabine/erlotinib (an EGFR inhibitor). This outcome is remarkable in the late-line PDAC treatment setting and is unusual after the progression of the tumor on gemcitabine/nab-paclitaxel chemotherapy.

Conclusion

This case suggests that gemcitabine/erlotinib could be an effective treatment in patients with PDAC and co-occurrence of EGFR and KRAS mutations.

Metastatic Pancreatic Adenocarcinoma Downstaged to T0N0 with Chemotherapy and Targeted Therapy, Confirmed by Surgical Pathology: A Case Report

Introduction

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive human tumor that is typically diagnosed at a later stage when surgery is not possible.

Case Presentation

We report the case of a 62-year-old woman who presented to the emergency department with abdominal pain. Computed tomography (CT) revealed a solitary hepatic lesion and a pancreatic body lesion. The pancreatic body lesion was biopsied endoscopically, and a tissue diagnosis was obtained to confirm the diagnosis of PDAC. She was then treated with 12 cycles of FOLFIRINOX with stable disease on CT. Due to the history of a hepatic lesion, she received 11 cycles of gemcitabine/Abraxane and a combination of a MEK inhibitor, Mekinist, and a BRAF inhibitor, BRAFTOVI. Subsequently, the patient underwent a liver biopsy. The biopsy result was negative, and the tumor was deemed resectable. The patient underwent a distal pancreatectomy. Surgical pathology demonstrated a 1.1-cm low-grade papillary mucinous neoplasm with negative margins and lymph nodes, staged T0N0. Adjuvant chemotherapy was not administered.

Conclusion

To our knowledge, this is the first report of a patient with metastatic pancreatic adenocarcinoma who received prolonged IV and oral chemotherapy. At the time of the operation, the pathological stage was T0N0. The patient has recently been seen 9 months after surgery with no evidence cancer recurrence. Additionally, ctDNA remains negative.

Cell surface GRP78-directed CAR-T cells are effective at treating human pancreatic cancer in preclinical models

Pancreatic cancer is a highly lethal solid malignancy with limited treatment options. Chimeric antigen receptor T (CAR-T) cell therapy has been successfully applied to treat hematological malignancies, but faces many challenges in solid tumors. One major challenge is the shortage of tumor-selective targets. Cell surface GRP78 (csGRP78) is highly expressed on various solid cancer cells including pancreatic cancer, but not normal cells, providing a potential target for CAR-T cell therapy in pancreatic cancer. Here, we demonstrated that csGRP78-directed CAR-T (GRP78-CAR-T) cells effectively killed the human pancreatic cancer cell lines Bxpc-3-luc, Aspc-1-luc and MIA PaCa-2-luc, and pancreatic cancer stem-like cells derived from Aspc-1-luc cells and MIA PaCa-2-luc cells in vitro by a luciferase-based cytotoxicity assay. Importantly, we showed that GRP78-CAR-T cells efficiently homed to and infiltrated Aspc-1-luc cell-derived xenografts and significantly inhibited pancreatic tumor growth in vivo by performing mouse xenograft experiments. Interestingly, we found that gemcitabine treatment increased csGRP78 expression in gemcitabine-resistant MIA PaCa-2-luc cells, and the coapplication of gemcitabine with GRP78-CAR-T cells led to a robust cytotoxic effect on these cells in vitro. Taken together, our study demonstrates that csGRP78-directed CAR-T cells, alone or in combination with chemotherapy, selectively and efficiently target csGRP78-expressing pancreatic cancer cells to suppress pancreatic tumor growth.

Pancreatic ductal adenocarcinoma complete regression after preoperative chemotherapy: Surgical results in a small series

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) becomes a systemic disease from an early stage. Complete surgical resection remains the only validated and potentially curative treatment; disappointingly only 20% of patients present with a resectable tumour. Although a complete pathological regression (pCR) after the preoperative chemotherapy could intuitively lead to better outcomes and prolonged survival some reports highlighted significant rates of recurrence.

CASES PRESENTATION

We describe three cases of pCR following preoperative chemotherapy for PDAC. The first two cases received neoadjuvant mFOLFIRINOX and PAX-G scheme for borderline resectable PDAC. Recurrence appeared 9 and 12 months after surgery. Although both patients started adjuvant therapy straight after the diagnosis of recurrence, the disease rapidly progressed and led them to death 12 and 15 months after surgery. The third case was characterized by germline BRCA2 mutation. The patient presented with PDAC of the body, intrapancreatic biliary stenosis and suspected peritoneal metastasis. One year later, after first and second-line chemotherapy, she underwent explorative laparoscopy and total spleno-pancreatectomy without evidence of viable tumour cells in the surgical specimen. At six months she is recurrence-free.

CONCLUSIONS

Very few reports describe a complete pathological response following preoperative chemotherapy in pancreatic cancer. We observed three cases in the last three years with disappointing oncological results. Further investigations are needed to predict PDAC prognosis in pCR after chemotherapy.

Immunotherapy and Pancreatic Cancer: A Lost Challenge?

Although immunotherapy has proved to be a very efficient therapeutic strategy for many types of tumors, the results for pancreatic cancer (PC) have been very poor. Indeed, chemotherapy remains the standard treatment for this tumor in the advanced stage. Clinical data showed that only a small portion of PC patients with high microsatellite instability/mismatch repair deficiency benefit from immunotherapy. However, the low prevalence of these alterations was not sufficient to lead to a practice change in the treatment strategy of this tumor. The main reasons for the poor efficacy of immunotherapy probably lie in the peculiar features of the pancreatic tumor microenvironment in comparison with other malignancies. In addition, the biomarkers usually evaluated to define immunotherapy efficacy in other cancers appear to be useless in PC. This review aims to describe the main features of the pancreatic tumor microenvironment from an immunological point of view and to summarize the current data on immunotherapy efficacy and immune biomarkers in PC.

A Novel 3DNA® Nanocarrier effectively delivers payloads to pancreatic tumors

INTRODUCTION

Standard-of-care systemic chemotherapies for pancreatic ductal adenocarcinoma (PDAC) currently have limited clinical benefits, in addition to causing adverse side effects in many patients. One factor known to contribute to the poor chemotherapy response is the poor drug diffusion into PDAC tumors. Novel treatment methods are therefore drastically needed to improve targeted delivery of treatments. Here, we evaluated the efficacy of the 3DNA® Nanocarrier (3DNA) platform to direct delivery of therapeutics to PDAC tumors in vivo.

MATERIALS AND METHODS

A panel of PDAC cell lines and a patient tissue microarray were screened for established tumor-specific proteins to identify targeting moieties for active targeting of the 3DNA. NRG mice with or without orthotopic MIA PaCa-2-luciferase PDAC tumors were treated intraperitoneally with 100 μl of fluorescently labeled 3DNA.

RESULTS

Folic acid and transferrin receptors were significantly elevated in PDAC compared to normal pancreas. Accordingly, both folic acid- and transferrin-conjugated 3DNA treatments significantly increased delivery of 3DNA specifically to tumors in comparison to unconjugated 3DNA treatment. In the absence of tumors, there was an increased clearance of both folic acid-conjugated 3DNA and unconjugated 3DNA, compared to the clearance rate in tumor-bearing mice. Lastly, delivery of siLuciferase by folic acid-conjugated 3DNA in an orthotopic model of luciferase-expressing PDAC showed significant and prolonged suppression of luciferase protein expression and activity.

CONCLUSION

Our study progresses the 3DNA technology as a reliable and effective treatment delivery platform for targeted therapeutic approaches in PDAC.

Targeting ZDHHC9 potentiates anti-programmed death-ligand 1 immunotherapy of pancreatic cancer by modifying the tumor microenvironment

Immune checkpoint blockade (ICB) therapy targeting the programmed death 1/programmed death-ligand 1 (PD-1/PD-L1) axis has achieved considerable success in treating a wide range of cancers. However, most patients with pancreatic cancer remain resistant to ICB. Moreover, there is a lack of optimal biomarkers for the prediction of response to this therapy. Palmitoylation is mediated by a family of 23 S-acyltransferases, termed zinc finger Asp-His-His-Cys-type palmitoyltransferases (ZDHHC), which precisely control various cancer-related protein functions and represent promising drug targets for cancer therapy. Here, we revealed that tumor cell-intrinsic ZDHHC9 was overexpressed in pancreatic cancer tissues and associated with impaired anti-tumor immunity. In syngeneic pancreatic tumor models, the knockdown of ZDHHC9 expression suppressed tumor progression and prolonged survival time of mice by modifying the immunosuppressive ('cold') to proinflammatory ('hot') tumor microenvironment. Furthermore, ZDHHC9 deficiency sensitized anti-PD-L1 immunotherapy mainly in a CD8+ T cell dependent manner. Lastly, we employed the ZDHHC9-siRNA nanoparticle system to efficiently silence ZDHHC9 in pancreatic tumors. Collectively, our findings indicate that ZDHHC9 overexpression in pancreatic tumors is a mechanism involved in the inhibition of host anti-tumor immunity and highlight the importance of inactivating ZDHHC9 as an effective immunotherapeutic strategy and booster for anti-PD-L1 therapy against pancreatic cancer.

T-cell exhaustion signatures characterize the immune landscape and predict HCC prognosis via integrating single-cell RNA-seq and bulk RNA-sequencing

Background

Hepatocellular carcinoma (HCC), the third most prevalent cause of cancer-related death, is a frequent primary liver cancer with a high rate of morbidity and mortality. T-cell depletion (TEX) is a progressive decline in T-cell function due to continuous stimulation of the TCR in the presence of sustained antigen exposure. Numerous studies have shown that TEX plays an essential role in the antitumor immune process and is significantly associated with patient prognosis. Hence, it is important to gain insight into the potential role of T cell depletion in the tumor microenvironment. The purpose of this study was to develop a trustworthy TEX-based signature using single-cell RNA-seq (scRNA-seq) and high-throughput RNA sequencing, opening up new avenues for evaluating the prognosis and immunotherapeutic response of HCC patients.

Methods

The International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA) databases were used to download RNA-seq information for HCC patients. The 10x scRNA-seq. data of HCC were downloaded from GSE166635, and UMAP was used for clustering descending, and subgroup identification. TEX-related genes were identified by gene set variance analysis (GSVA) and weighted gene correlation network analysis (WGCNA). Afterward, we established a prognostic TEX signature using LASSO-Cox analysis. External validation was performed in the ICGC cohort. Immunotherapy response was assessed by the IMvigor210, GSE78220, GSE79671, and GSE91061cohorts. In addition, differences in mutational landscape and chemotherapy sensitivity between different risk groups were investigated. Finally, the differential expression of TEX genes was verified by qRT-PCR.

Result

11 TEX genes were thought to be highly predictive of the prognosis of HCC and substantially related to HCC prognosis. Patients in the low-risk group had a greater overall survival rate than those in the high-risk group, according to multivariate analysis, which also revealed that the model was an independent predictor of HCC. The predictive efficacy of columnar maps created from clinical features and risk scores was strong.

Conclusion

TEX signature and column line plots showed good predictive performance, providing a new perspective for assessing pre-immune efficacy, which will be useful for future precision immuno-oncology studies.

Identification of the molecular subtype and prognostic characteristics of pancreatic cancer based on CD8 + T cell-related genes

CD8 + T lymphocytes are immune cells that play a crucial anti-tumor role in the human body, and prognostic value of CD8 + T cell-related regulatory genes in PAAD remains elusive. Data on 179 expression profiles across 13 immune cell datasets were downloaded from the GEO database, and the expression profiles of CD8 + T cell-related genes were obtained using WGCNA. Molecular subtypes based on CD8 + T cell-related genes were constructed using the ConsensusClusterPlus algorithm. Lasso regression analysis was performed to build a 10-gene signature. GSVA was performed to explore the pathways related to these ten genes. The IMvigor210 cohort was used to explore the predictive efficacy of the signature in terms of immunotherapy response. Four hundred and forty-six CD8 + T cell-related genes were obtained. One hundred and nine genes in TCGA and GEO datasets were closely related to the prognosis of patients and were included in the next study. PAAD samples were divided into two subtypes (IC1 and IC2) according to consensus cluster analysis. These two immune subtypes were significantly different in terms of immune checkpoint genes, immune function, and drug treatment response. Additionally, the 10-gene signature constructed based on CD8 + T cell-related genes showed a stable prognostic performance in TCGA and GEO cohorts. Moreover, it served as an independent prognostic factor for patients with PAAD. Furthermore, the 10-gene signature could effectively predict the response to immunotherapy. The immunophenotyping-derived prognostic model based on CD8 T cell-related genes provides a basis for the clinical treatment of pancreatic cancer.

Prognostic value of circulating T-lymphocyte subsets in advanced pancreatic cancer patients treated with mFOLFIRINOX or gemcitabine

Advanced pancreatic ductal adenocarcinoma (PDAC) is commonly treated with a chemotherapy combination of mFOLFIRINOX or gemcitabine. However, predictive and prognostic factors for choosing a more appropriate treatment strategy are still lacking. This study aimed to evaluate how chemotherapy changes immune system parameters and whether these changes influence survival outcomes. We sought to identify an easily accessible marker to help choose the appropriate treatment. Patients with PDAC who were suitable for systemic chemotherapy were eligible for the study. Peripheral blood samples were obtained at baseline and after two months of treatment. Lymphocyte subsets were measured using flow cytometry. Correlation with clinical features and survival analyses were performed. In total, 124 patients were enrolled in this study. Seventy patients were treated with mFOLFIRINOX and 50 with gemcitabine monotherapy. Four patients could not be treated because of rapid deterioration. During overall survival analysis (OS), significant factors included age, Eastern Cooperative Oncology Group (ECOG) performance status, differentiation grade G3, carcinoma antigen (CA) 19-9 more than 100 kU/L, absolute white blood cell count, CD3 + CD8+, and CD8 + CD57-T lymphocytes. Natural killer CD3-CD56 + CD16 + and CD3-CD56 + CD16- and T regulatory CD4 + FOXP3 + and CD3 + CD56 + cells differed during treatment, but these differences did not influence the survival results. At baseline, CD8 + CD57- T lymphocyte count demonstrated a clear independent impact on progression-free survival and OS. Gemcitabine showed better survival in patients with extremely low baseline CD8 + CD57- levels. Therefore, circulating CD3 + CD8 + and CD8 + CD57- cells measured before treatment in PDAC may be considered prognostic and predictive biomarkers.

The association between CD3+ and CD8+tumor-infiltrating lymphocytes (TILs) and prognosis in patients with pancreatic adenocarcinoma

BACKGROUND

Pancreatic adenocarcinoma (PDAC), with more than 250,000 deaths each year, is the eighth leading cause of death worldwide, with a five-year survival of less than 5% and a median recurrence time between 5 and 23 months. The association between PDAC and CD3⁺/CD8⁺ tumor-infiltrating lymphocytes (TILs) and the extent of tumor spread and clinical outcomes has been recently shown. This study aimed to determine and compare the density of TILs and their association with disease prognosis in patients with PDAC.

MATERIALS AND METHODS

In this study, we collected PDAC tissues and corresponding adjacent normal tissues from 64 patients with TIL-positive PDAC. The immunohistochemistry method was used for the detection of the expression levels of CD3⁺ and CD8⁺ TILs in PDAC tissues. Also, the completed follow-up history was evaluated for at least five years.

RESULTS

The frequency of intratumoral and peritumoral TILs was 20 (31.2%) and 44 (68.8%), respectively. The mean density of CD3⁺ TILs and CD8⁺ TILs was 67.73%±20.17% and 69.45%±17.82%, respectively. The density of CD3⁺ TILs and CD8⁺ TILs was not associated with overall survival nor metastasis-free survival of the patients and tumor grade. However, the density of TILs was significantly lower in those patients who experienced tumor recurrence than those without this recurrence.

CONCLUSION

TILs density was high in patients with PDAC. The density of both CD3⁺ and CD8⁺ TILs was significantly lower in patients who experienced tumor recurrence. Thus, this study suggests that tracking and determining the density of CD3⁺ and CD8⁺ TILs might be effective in predicting PDAC recurrence.

MicroRNAs and long non-coding RNAs in pancreatic cancer: From epigenetics to potential clinical applications

MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are two relevant classes of non-coding RNAs (ncRNAs) that play a pivotal role in a number of molecular processes through different epigenetic regulatory mechanisms of gene expression. As a matter of fact, the altered expression of these types of RNAs leads to the development and progression of a varied range of multifactorial human diseases. Several recent reports elucidated that miRNA and lncRNAs have been implicated in pancreatic cancer (PC). For instance, dysregulation of such ncRNAs has been found to be associated with chemoresistance, apoptosis, autophagy, cell differentiation, tumor suppression, tumor growth, cancer cell proliferation, migration, and invasion in PC. Moreover, several aberrantly expressed miRNAs and lncRNAs have the potential to be used as biomarkers for accurate PC diagnosis. Additionally, miRNAs and lncRNAs are considered as promising clinical targets for PC. Therefore, in this review, we discuss recent experimental evidence regarding the clinical implications of miRNAs and lncRNAs in the pathophysiology of PC, their future potential, as well as the challenges that have arisen in this field of study in order to drive forward the design of ncRNA-based diagnostics and therapeutics for PC.

TYRO3 promotes chemoresistance via increased LC3 expression in pancreatic cancer

Pancreatic cancer (PC) is an aggressive malignancy with few treatment options, and improved treatment strategies are urgently required. TYRO3, a member of the TAM receptor tyrosine kinase family, is a known oncogene; however, the relationship between TYRO3 expression and PC chemoresistance remains to be elucidated. We performed gain- and loss-of-function experiments on TYRO3 to examine whether it is involved in chemoresistance in PC cells. TYRO3 knockdown decreased cell viability and enhanced apoptosis following treatment of PC cells with gemcitabine and 5-fluorouracil (5-FU). In contrast, no such effects were observed in TYRO3-overexpressing PC cells. It is known that autophagy is associated with cancer chemoresistance. We then examined effects of TYRO3 on autophagy in PC cells. TYRO3 overexpression increased LC3 mRNA levels and induced LC3 puncta in PC cells. Inhibition of autophagy by chloroquine mitigated cell resistance to gemcitabine and 5-FU. In a xenograft mouse model, TYRO3 silencing significantly increased sensitivity of the cells to gemcitabine and 5-FU. To further investigate the involvement of autophagy in patients with PC, we immunohistochemically analyzed LC3 expression in the tissues of patients who underwent pancreatectomy and compared it with disease prognosis and TYRO3 expression. LC3 expression was negatively and positively correlated with prognosis and TYRO3 expression, respectively. Furthermore, LC3- and TYRO3-positive patients had a significantly worse prognosis among patients with PC who received chemotherapy after recurrence. These results indicated that the TYRO3-autophagy signaling pathway confers PC resistance to gemcitabine and 5-FU, and could be a novel therapeutic target to resolve PC chemoresistance.

The molecular, immune features, and risk score construction of intraductal papillary mucinous neoplasm patients

Intraductal papillary mucinous neoplasm (IPMN) is a common pancreatic precancerous lesion, with increasing incidence in recent years. However, the mechanisms of IPMN progression into invasive cancer remain unclear. The mRNA expression data of IPMN/PAAD patients were extracted from the TCGA and GEO databases. First, based on GSE19650, we analyzed the molecular alterations, tumor stemness, immune landscape, and transcriptional regulation of IPMN progression. The results indicated that gene expression changed dramatically, specifically at the intraductal papillary-mucinous adenoma (IPMA) stage. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Kyoto Encyclopedia of Genes and Genomes (GSEA) pathway analyses showed that glycoprotein-related, cell cycle, and P53 pathways displayed the most significant changes during progression. With IPMN progression, tumor stemness increased continuously, and KRAS, ERBB3, RUNX1, and ELF3 are essential driver genes affecting tumor stemness. Motif analysis suggested that KLF4 may be a specific transcription factor that regulates gene expression in the IPMA stage, while MYB and MYBL1 control gene expression in the IPMC and invasive stages, respectively. Then, GSE19650 and GSE71729 transcriptome data were combined to perform the least absolute shrinkage and selection operator (LASSO) method and Cox regression analysis to develop an 11-gene prediction model (KCNK1, FHL2, LAMC2, CDCA7, GPX3, C7, VIP, HBA1, BTG2, MT1E, and LYVE1) to predict the prognosis of pancreatic cancer patients. The reliability of the model was validated in the GSE71729 and TCGA databases. Finally, 11 additional IPMN patients treated in our hospital were included, and the immune microenvironment changes during IPMN progression were analyzed by immunohistochemistry (IHC). IHC results suggest that Myeloid-derived suppressor cells (MDSCs) and macrophages may be key in the formation of immunosuppressive microenvironment of IPMN progression. Our study deepens our understanding of IPMN progression, especially the changes in the immune microenvironment. The findings of this work may contribute to the development of new therapeutic strategies for IPMN.

Clinical Outcome and Prognostic Factors of Pancreatic Adenosquamous Carcinoma Compared to Ductal Adenocarcinoma-Results from the German Cancer Registry Group

Background: Adenosquamous carcinoma of the pancreas (ASCP) is a rare malignancy and its pathophysiology is poorly understood. Sparse clinical data suggest that clinical outcome and overall survival is worse in comparison to common pancreatic ductal adenocarcinoma (PDAC). Methods: We evaluated clinical outcome and prognostic factors for overall survival of patients with ASCP in comparison to patients with PDAC recorded between 2000 and 2019 in 17 population-based clinical cancer registries at certified cancer centers within the Association of German Tumor Centers (ADT). Results: We identified 278 (0.5%) patients with ASCP in the entire cohort of 52,518 patients with pancreatic cancer. Significantly, more patients underwent surgical resection in the cohort of ASCP patients in comparison to patients with PDAC (p < 0.001). In the cohort of 142 surgically resected patients with ASCP, the majority of patients was treated by pancreatoduodenectomy (44.4%). However, compared to the cohort of PDAC patients, significantly more patients underwent distal pancreatectomy (p < 0.001), suggesting that a significantly higher proportion of ASCP tumors was located in the pancreatic body/tail. ASCPs were significantly more often poorly differentiated (G3) (p < 0.001) and blood vessel invasion (V1) was detected more frequently (p = 0.01) in comparison with PDAC. Median overall survival was 6.13 months (95% CI 5.20−7.06) for ASCP and 8.10 months (95% CI 7.93−8.22) for PDAC patients, respectively (p = 0.094). However, when comparing only those patients who underwent surgical resection, overall survival of ASCP patients was significantly shorter (11.80; 95% CI 8.20−15.40 months) compared to PDAC patients (16.17; 95% CI 15.78−16.55 months) (p = 0.007). ASCP was a highly significant prognostic factor for overall survival in univariable regression analysis (p = 0.007) as well as in multivariable Cox regression analysis (HR 1.303; 95% CI 1.013−1.677; p = 0.039). Conclusions: In conclusion, ASCP showed poorer differentiation and higher frequency of blood vessel invasion indicative of a more aggressive tumor biology. ASCP was a significant prognostic factor for overall survival in a multivariable analysis. Overall survival of resected ASCP patients was significantly shorter compared to resected PDAC patients. However, surgical resection still improved survival significantly.

Cellular metabolism in pancreatic cancer as a tool for prognosis and treatment (Review)

Pancreatic cancer (PC) has one of the highest fatality rates and the currently available therapeutic options are not sufficient to improve its overall poor prognosis. In addition to insufficient effectiveness of anticancer treatments, the lack of clear early symptoms and early metastatic spread maintain the PC survival rates at a low level. Metabolic reprogramming is among the hallmarks of cancer and could be exploited for the diagnosis and treatment of PC. PC is characterized by its heterogeneity and, apart from molecular subtypes, the identification of metabolic subtypes in PC could aid in the development of more individualized therapeutic approaches and may lead to improved clinical outcomes. In addition to the deregulated utilization of glucose in aerobic glycolysis, PC cells can use a wide range of substrates, including branched‑chain amino acids, glutamine and lipids to fulfil their energy requirements, as well as biosynthetic needs. The tumor microenvironment in PC supports tumor growth, metastatic spread, treatment resistance and the suppression of the host immune response. Moreover, reciprocal interactions between cancer and stromal cells enhance their metabolic reprogramming. PC stem cells (PCSCs) with an increased resistance and distinct metabolic properties are associated with disease relapses and cancer spread, and represent another significant candidate for therapeutic targeting. The present review discusses the metabolic signatures observed in PC, a disease with a multifaceted and often transient metabolic landscape. In addition, the metabolic pathways utilized by PC cells, as well as stromal cells are discussed, providing examples of how they could present novel targets for therapeutic interventions and elaborating on how interactions between the various cell types affect their metabolism. Furthermore, the importance of PCSCs is discussed, focusing specifically on their metabolic adaptations.

Immunotherapy in Pancreatic Cancer: Why Do We Keep Failing? A Focus on Tumor Immune Microenvironment, Predictive Biomarkers and Treatment Outcomes

Simple Summary

In pancreatic cancer, immunotherapy and targeted therapies have not brought about the therapeutic revolution that has been observed in other malignancies. Among the reasons to explain this difference is the possibly crucial role played by the pancreatic tumor microenvironment, which has unique features and is different from that of other neoplasms. The aim of this review is to provide a comprehensive overview of the distinctive tumor immune microenvironment of pancreatic cancer and to summarize existing data about the use of immunotherapy and immune biomarkers in this cancer.

Abstract

The advent of immunotherapy and targeted therapies has dramatically changed the outcomes of patients affected by many malignancies. Pancreatic cancer (PC) remains one the few tumors that is not treated with new generation therapies, as chemotherapy still represents the only effective therapeutic strategy in advanced-stage disease. Agents aiming to reactivate the host immune system against cancer cells, such as those targeting immune checkpoints, failed to demonstrate significant activity, despite the success of these treatments in other tumors. In many cases, the proportion of patients who derived benefits in early-phase trials was too small and unpredictable to justify larger studies. The population of PC patients with high microsatellite instability/mismatch repair deficiency is currently the only population that may benefit from immunotherapy; nevertheless, the prevalence of these alterations is too low to determine a real change in the treatment scenario of this tumor. The reasons for the unsuccess of immunotherapy may lie in the extremely peculiar tumor microenvironment, including distinctive immune composition and cross talk between different cells. These unique features may also explain why the biomarkers commonly used to predict immunotherapy efficacy in other tumors seem to be useless in PC. In the current paper, we provide a comprehensive and up-to-date review of immunotherapy in PC, from the analysis of the tumor immune microenvironment to immune biomarkers and treatment outcomes, with the aim to highlight that simply transferring the knowledge acquired on immunotherapy in other tumors might not be a successful strategy in patients affected by PC.

Secretin Receptor as a Target in Gastrointestinal Cancer: Expression Analysis and Ligand Development

Secretin was originally discovered as a gastrointestinal peptide that stimulates fluid secretion from the pancreas and liver and delays gastric emptying. In disease, a secretin receptor (SCTR) was found to occur as a splice variant in gastrinoma and pancreatic adenocarcinoma. Overexpression of SCTR has been described for gastrinomas, carcinoid tumors of the lung and cholangiocarcinoma. SCTR therefore is considered a candidate target for molecular tumor imaging as well as for peptide receptor radioligand therapy (PRRT) in a number of oncological indications. The aim of this study was to characterize SCTR expression in esophageal and pancreatic cancer, demonstrating for the first time high SCTR overexpression in these tumor types. In total, 65 of 70 pancreatic ductal adenocarcinoma tissues stained strongly positive for SCTR in immunohistochemistry, as did most of the 151 esophageal cancer samples, with minor influence of grading in both entities. In addition, the aim of this study was to further delineate residues in human secretin that are critical for binding to and activation of human SCTR. For a potential development of short and metabolically stable analogs for clinical use, it was intended to probe the peptide for its capacity to incorporate deletions and substitutions without losing its affinity to SCTR. In a systematic approach, a library of 146 secretin variants containing single amino acid substitutions as well as truncations on either end was tested in β-arrestin2-GFP translocation and fluorescent ligand internalization assays employing high-content analysis, in cAMP assays which run in agonist and antagonist mode, and in radioligand binding. The main structural determinants of SCTR binding and activation were localized to the N-terminus, with His1, Asp3 being among the most sensitive positions, followed by Phe6, Thr7 and Leu10. Aminoterminal truncation caused a rapid decline in receptor activity and most of these variants proved to be partial agonists showing antagonistic properties. In this study, the most potent novel antagonist showed an IC50 of 309 ± 74 nM in the β-arrestin2-GFP translocation assay on human SCTR while remaining a weak partial agonist. Future studies will have to demonstrate the utility of further enhanced secretin analogues as tracers for in vivo imaging and therapy.

Pathogenic mitochondrial dysfunction and metabolic abnormalities

Herein we trace links between biochemical pathways, pathogenesis, and metabolic diseases to set the stage for new therapeutic advances. Cellular and acellular microorganisms including bacteria and viruses are primary pathogenic drivers that cause disease. Missing from this statement are subcellular compartments, importantly mitochondria, which can be pathogenic by themselves, also serving as key metabolic disease intermediaries. The breakdown of food molecules provides chemical energy to power cellular processes, with mitochondria as powerhouses and ATP as the principal energy carrying molecule. Most animal cell ATP is produced by mitochondrial synthase; its central role in metabolism has been known for >80 years. Metabolic disorders involving many organ systems are prevalent in all age groups. Progressive pathogenic mitochondrial dysfunction is a hallmark of genetic mitochondrial diseases, the most common phenotypic expression of inherited metabolic disorders. Confluent genetic, metabolic, and mitochondrial axes surface in diabetes, heart failure, neurodegenerative disease, and even in the ongoing coronavirus pandemic.