Liver Metastasis Of Pancreatic Cancer Research Articles

Comprehensive analysis of bulk and single-cell transcriptomic data reveals a novel signature associated with endoplasmic reticulum stress, lipid metabolism, and liver metastasis in pancreatic cancer

BackgroundPancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with high probability of recurrence and distant metastasis. Liver metastasis is the predominant metastatic mode developed in most pancreatic cancer cases, which seriously affects the overall survival rate of patients. Abnormally activated endoplasmic reticulum stress and lipid metabolism reprogramming are closely related to tumor growth and metastasis. This study aims to construct a prognostic model based on endoplasmic reticulum stress and lipid metabolism for pancreatic cancer, and further explore its correlation with tumor immunity and the possibility of immunotherapy.MethodsTranscriptomic and clinical data are acquired from TCGA, ICGC, and GEO databases. Potential prognostic genes were screened by consistent clustering and WGCNA methods, and the whole cohort was randomly divided into training and testing groups. The prognostic model was constructed by machine learning method in the training cohort and verified in the test, TCGA and ICGC cohorts. The clinical application of this model and its relationship with tumor immunity were analyzed, and the relationship between endoplasmic reticulum stress and intercellular communication was further explored.ResultsA total of 92 characteristic genes related to endoplasmic reticulum stress, lipid metabolism and liver metastasis were identified in pancreatic cancer. We established and validated a prognostic model for pancreatic cancer with 7 signatures, including ADH1C, APOE, RAP1GAP, NPC1L1, P4HB, SOD2, and TNFSF10. This model is considered to be an independent prognosticator and is a more accurate predictor of overall survival than age, gender, and stage. TIDE score was increased in high-risk group, while the infiltration levels of CD8+ T cells and M1 macrophages were decreased. The number and intensity of intercellular communication were increased in the high ER stress group.ConclusionsWe constructed and validated a novel prognostic model for pancreatic cancer, which can also be used as an instrumental variable to predict the prognosis and immune microenvironment. In addition, this study revealed the effect of ER stress on cell–cell communication in the tumor microenvironment.

Abstract 1590: The role of mucosal associated invariant T (MAIT) cells in pancreatic cancer liver metastasis

Abstract Pancreatic cancer liver metastasis (PCLM) is present in 50% of patients diagnosed with pancreatic ductal adenocarcinoma (PDAC) and leads to a median survival of <6 months. Here, we sought to identify urgently needed therapeutic options for treating PCLM by targeting mucosal associated invariant T (MAIT) cells, an invariant T cell restricted to MHCI related protein (MR1). MAIT cells are a unique subset of T cells that are classified as “protumor” MAIT17 and “antitumor” MAIT1 cells. We hypothesize that the PCLM tumor microenvironment (TME) induces direct MAIT cell activation via MR1 which primes MAIT cells towards a “protumor” phenotype. Using publicly available TCGA data, we found that PDAC tumors were enriched for MR1 gene expression compared to healthy tissue and patients with lower tumor MR1 expression had better overall survival. Next, immunostaining of MR1 on tumor samples from primary PDAC and PCLM revealed that that MR1 protein expression is highly enriched in the TME and localized to the surface of tumor cells. This suggests that MAIT cells in the PCLM TME are being activated directly via an MR1 dependent pathway. Next, we performed hemi-spleen injection of mouse pancreatic cancer cells into WT and MR1 KO (lacks MAIT cells) mice to model PCLM. Interestingly, MAIT cells in the WT PCLM mice were shifted towards the “pro-tumor” MAIT17 phenotype. Furthermore, the lack of MAIT cells in MR1 KO mice significantly reduced tumor burden compared to WT mice. Lastly, we found that MR1 KO mice had a reduction in exhausted NK and NKT cells which likely promoted anti-tumor immunity. Overall, we find that the PCLM TME promotes “pro-tumor” MAIT17 cells via MR1 mediated activation and these MAIT17 cells inhibit anti-tumor cells such as NK and NKT cells. This work identifies targeting MAIT cells as a novel immunotherapy approach for PCLM. Citation Format: Jugmohit Toor, Peter Dimitrion, Rachel Krevh, Kalpana Subedi, Bobby Zuniga, Jie Wang, Li Zhou, Qing-Sheng Mi. The role of mucosal associated invariant T (MAIT) cells in pancreatic cancer liver metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1590.

Abstract 4132: Low-dose carbon monoxide therapies suppress cancer metastasis

Abstract Metastasis is the primary cause of cancer-related deaths. Novel systemic therapies for metastatic cancer are urgently needed. Carbon monoxide (CO) is an endogenously produced signaling molecule in the human body with demonstrated pharmacological activities, including organ protection and anti-inflammation. We determined the therapeutic effect of low-dose CO and CO prodrugs on cancer progression in this study. We found that low-dose CO inhibits the migration of cancer cell lines including breast, pancreatic, colon, prostate, liver, and lung cancer. We showed that low-dose CO inhibits lung metastasis of breast cancer and liver metastasis of pancreatic cancer in preclinical mouse models. Further, to provide safer and more reliable CO delivery, we developed metal-free, organic CO prodrugs and showed that CO prodrugs inhibit tumor growth and metastasis. We demonstrated that low-dose CO blocks the transcription of heme importers, leading to diminished intracellular heme levels. Altogether, our work lays a strong foundation for the development of CO-based systemic cancer therapies. Citation Format: Tiantian Zhang, Cheryl Zhang, Xiang Chen, Xiaoxiao Yang, Qiyue Mao, George Zhang, Zhengming Chen, Adrian Tan, Jenny Zhaoying Xiang, Erika Hissong, Yao-Tseng Chen, Binghe Wang, Nancy Du. Low-dose carbon monoxide therapies suppress cancer metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4132.

Abstract 4128: Biofield therapy suppressed invasion and metastases of human pancreatic cancer

Abstract The NIH categorizes Biofield Therapy (BT) as therapeutic approaches within energy medicine that involve using the body's energy field (biofield) for therapeutic benefit. Although controversial, in some cases devices have been developed that mimic the electromagnetic fields (EMF) that are emitted from people when delivering BTs. We previously reported that BT significantly inhibited the growth of pancreatic cancer cells and liver metastasis in their relevant animal models mediated in part through modification of the cell cycle, reductions in cell voltage potentials, and down regulation of PI3K/Akt pathways. We expanded this research to examine the potential role of BT in anti-invasiveness in human pancreatic ductal adenocarcinoma (PDAC) cells and animal models. We found that PANC-1 cells treated with BT (15 min) displayed 55% less invading cells than that of untreated incubator control and sham control cells (P < 0.001). Similar results were observed in human PDAC L3.7 cells and mouse pancreatic cancer KPCY cells. These experiments were replicated 8 times for Panc-1 cells and 4 times for L3.7 cells. Additionally, migration capacity was tested using the transwell migration and scratch assays. Consistent with the result of cell invasion assays, BT treatment also led to significant reduction of migration of PANC-1 and L3.7 cells by 34% and 41%, respectively, compared to sham controls. Two additional therapists independently replicated the anti-invasiveness and anti-migratory effects of BT on these PDAC cells. This suggests the replicability of these findings across studies and therapists. In a repeated PANC-1 mouse orthotopic model, we found that only a third of BT treated mice had visible liver nodules whereas liver metastasis was observed in more than half of mice in the untreated colony control and sham control groups. Furthermore, BT treatment significantly reduced liver tumor burden by 73% compared to that of the sham control group (p < 0.05), which was similar to that observed in the previous study. Similar to the prior PANC-1 mouse model, in the current study BT treatment had only a moderate impact on the growth of primary pancreatic tumor. We assessed certain markers indicative of cell status as well as pathways associated with migration and invasion and these will be presented at the meeting. Our findings suggest that exposure to BT reduced cellular invasion and migration processes and profoundly reduced metastasis of pancreatic tumor in an animal model. This study is in part supported by Emerald Gate Charitable Trust. Citation Format: Peiying Yang, Sharmistha Chakraborty, Phuong Nguyen, Defeng Deng, Andrew Cusimano, Daoyan Wei, Lorenzo Cohen. Biofield therapy suppressed invasion and metastases of human pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4128.

Abstract 5373: Decoding the role of intrinsic pancreatic cellular signaling in shaping the immunosuppressive tumor microenvironment

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) has the highest mortality rate among major cancers, with over 50% of patients having liver metastases at diagnosis. Conventional T-cell-based immunotherapies are ineffective against PDAC liver metastases due to the intricate hepatic tumor microenvironment (TME) that hinders effective immune responses. Thus, it is vital to promote the influx of cytotoxic lymphocytes and prime antitumor immunity. PDAC cells exhibit plasticity and intrinsic cellular heterogeneity, leading to varying immune cell infiltrates and immune responses. Concurrently, early metastases to the liver create an immunosuppressive environment. Our study employs multiple PDAC models, originating from a congenic array of distinct PDAC cell clone tumors with varying degrees of T cell infiltration to delineate the signaling pathways that lead to immunosuppression in the pancreas and liver. Methods: The compendium of congenic PDAC murine cell clones mirrors immune heterogeneity observed in tumors, spanning from low to high T cell infiltration. To overcome a scarcity of tumor-specific neoepitopes in PDAC, we engineered PDAC cell clones expressing chicken ovalbumin (OVA) for antigen-specific T and B cell responses. By subcutaneous and intraportal vein injection of PDAC cell clones into mice, we induce primary pancreatic and metastatic liver tumors to explore immune phenotypes and assess anti-tumor adaptive immune responses, including myeloid and lymphoid cell subsets. Results: In vivo engraftment of PDAC clones showed varied CD4+/CD8+ T cells and polymorphonuclear myeloid-derived suppressor cells, accentuated with immunogenic OVA antigen expression. While all OVA+ PDAC lines elicited antigen-specific immune responses, only ‘TIL high’ tumors were eradicated, while ‘TIL low’ clones persisted in vivo. Additionally, ‘TIL low’ clones formed liver metastases upon intraportal injection, despite OVA expression. RNAseq unveiled differential expression in IL-1 family cytokines and receptors, chemokine-like factor gene superfamily, parathyroid hormone relevant function and metabolism. Current investigations include altering these pathways to re-program the tumor microenvironment and induce local immune suppression. Conclusion: Using diverse PDAC models, we created tumors with immune heterogeneity and altered transcriptional profiles. We identified validated differentially expressed immune altering cytokines, such as CXCL1 and CSF3, and potential novel IL-1 family genes and parathyroid signaling genes. The altered TME conferred protection against tumor antigen-specific immunity in certain clones, both in subcutaneous and liver metastasis models. Ongoing studies will assess the impact of these genes in the distinct environments, offering avenues for immunotherapeutic strategies targeting pancreatic cancer liver metastasis. Citation Format: Bushangqing Liu, Ethan Agritelley, Daniel Nussbaum, Junping Wei, Gangjun Lei, Melissa Gajda, Zachary Hartman. Decoding the role of intrinsic pancreatic cellular signaling in shaping the immunosuppressive tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5373.

Exploring the efficacy and safety of drug-eluting beads transarterial chemoembolization in pancreatic cancer liver metastasis.

Drug-eluting beads transarterial chemoembolization (DEB-TACE) has shown promise as a treatment modality for primary liver cancer and colorectal cancer liver metastasis. However, its role in pancreatic cancer liver metastasis (PCLM) remains uncertain. This study aimed to investigate the efficacy and safety of DEB-TACE in PCLM patients. A retrospective study included 10 PCLM patients who underwent DEB-TACE using CalliSpheres® microspheres as the chemoembolization material. Treatment response, survival outcomes, adverse events, and liver function indexes were comprehensively assessed. Among the patients, complete response, partial response, stable disease, and progressive disease rates were 0.0%, 40.0%, 30.0%, and 30.0%, respectively. The objective response rate was 40.0%, and the disease-control rate was 70.0%. The median progression-free survival (PFS) was 12.0 months (95% CI: 0.0-26.7), with a 1-year PFS rate of 48.0%. The median overall survival (OS) was 18.0 months (95% CI: 6.0-30.0), with a 1-year OS rate of 80.0%. Additionally, no significant differences were observed in any of the liver function indexes, including alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transpeptidase, etc., between pre- and posttreatment evaluations. Adverse events included pain, grade 1-2 vomiting, fever, and transient liver dysfunction. DEB-TACE demonstrates a promising treatment response, favorable survival profile, and satisfactory safety in PCLM patients. This study adds to the current research by providing novel evidence on the efficacy, safety, and favorable survival outcomes of DEB-TACE in treating PCLM, highlighting its potential as an effective therapeutic option in this specific population.

Efferocytosis reprograms the tumor microenvironment to promote pancreatic cancer liver metastasis.

Pancreatic ductal adenocarcinoma is a highly metastatic disease and macrophages support liver metastases. Efferocytosis, or engulfment of apoptotic cells by macrophages, is an essential process in tissue homeostasis and wound healing, but its role in metastasis is less well understood. Here, we found that the colonization of the hepatic metastatic site is accompanied by low-grade tissue injury and that efferocytosis-mediated clearance of parenchymal dead cells promotes macrophage reprogramming and liver metastasis. Mechanistically, progranulin expression in macrophages is necessary for efficient efferocytosis by controlling lysosomal acidification via cystic fibrosis transmembrane conductance regulator and the degradation of lysosomal cargo, resulting in LXRα/RXRα-mediated macrophage conversion and upregulation of arginase 1. Pharmacological blockade of efferocytosis or macrophage-specific genetic depletion of progranulin impairs macrophage conversion, improves CD8+ T cell functions, and reduces liver metastasis. Our findings reveal how hard-wired functions of macrophages in tissue repair contribute to liver metastasis and identify potential targets for prevention of pancreatic ductal adenocarcinoma liver metastasis.

Exosome-derived tRNA fragments tRF-GluCTC-0005 promotes pancreatic cancer liver metastasis by activating hepatic stellate cells

Early metastasis is the primary factor in the very poor prognosis of pancreatic ductal adenocarcinoma (PDAC), with liver metastasis being the most common form of distant metastasis in PDAC. To investigate the mechanism of PDAC liver metastasis, we found that PDAC cells can promote the formation of pre-metastatic niches (PMNs) through exosomes to facilitate liver metastasis in the early stage. In our study, hepatic stellate cells (HSCs) were treated with PDAC-derived exosomes (PDAC-exo), and the activation of HSCs was detected. A novel transfer RNA-derived fragment, the tRF-GluCTC-0005 was obtained by small RNA sequencing from serum exosomes of PDAC patients. Bioinformatics analysis and RNA pull-down assays revealed the interaction between WDR1 and tRF-GluCTC-0005. A KPC transgenic mouse model and an AAV-mediated sh-WDR1 mouse model were used to detect the mechanism of liver metastasis in vivo. Finally, the dual luciferase reporter assay, protein mutation truncation assay, Co-IP assay, and flow cytometry assay were used to explore the molecular mechanism in HSCs activation and PMNs formation. We found that the tRF-GluCTC-0005 in exosomes binds to the 3’ untranslated region of the mRNA of the WDRl in HSCs and increases mRNA stability. The N-terminals of WDR1 bind to the YAP protein directly, inhibit YAP phosphorylation, and promote the expression of YAP transcription factors. The tRF-GluCTC-0005 in PDAC-exo significantly recruits myeloid-derived suppressor cells (MDSCs) in the liver, creating a PMNs immunosuppressive microenvironment and further advancing liver metastasis from PDAC. Our results suggest that the key of PDAC liver metastasis is the activation of HSCs through upregulation of WDR1 by tRF-GluCTC-0005 in exosomes, which mediates the infiltration of MDSCs to form PMNs.

Molecular mechanisms of pancreatic cancer liver metastasis: the role of PAK2.

Pancreatic cancer remains an extremely malignant digestive tract tumor, posing a significant global public health burden. Patients with pancreatic cancer, once metastasis occurs, lose all hope of cure, and prognosis is extremely poor. It is important to investigate liver metastasis of Pancreatic cancer in depth, not just because it is the most common form of metastasis in pancreatic cancer, but also because it is crucial for treatment planning and prognosis assessment. This study aims to delve into the mechanisms of pancreatic cancer liver metastasis, with the goal of providing crucial scientific groundwork for the development of future treatment methods and drugs. We explored the mechanisms of pancreatic cancer liver metastasis using single-cell sequencing data (GSE155698 and GSE154778) and bulk data (GSE71729, GSE19279, TCGA-PAAD). Initially, Seurat package was employed for single-cell data processing to obtain expression matrices for primary pancreatic cancer lesions and liver metastatic lesions. Subsequently, high-dimensional weighted gene co-expression network analysis (hdWGCNA) was used to identify genes associated with liver metastasis. Machine learning algorithms and COX regression models were employed to further screen genes related to patient prognosis. Informed by both biological understanding and the outcomes of algorithms, we meticulously identified the ultimate set of liver metastasis-related gene (LRG). In the study of LRG genes, various databases were utilized to validate their association with pancreatic cancer liver metastasis. In order to analyze the effects of these agents on tumor microenvironment, we conducted an in-depth analysis, including changes in signaling pathways (GSVA), cell differentiation (pseudo-temporal analysis), cell communication networks (cell communication analysis), and downstream transcription factors (transcription factor activity prediction). Additionally, drug sensitivity analysis and metabolic analysis were performed to reveal the effects of LRG on gemcitabine resistance and metabolic pathways. Finally, functional experiments were conducted by silencing the expression of LRG in PANC-1 and Bx-PC-3 cells to validate its influence to proliferation and invasiveness on PANC-1 and Bx-PC-3 cells. Through a series of algorithmic filters, we identified PAK2 as a key gene promoting pancreatic cancer liver metastasis. GSVA analysis elucidated the activation of the TGF-beta signaling pathway by PAK2 to promote the occurrence of liver metastasis. Pseudo-temporal analysis revealed a significant correlation between PAK2 expression and the lower differentiation status of pancreatic cancer cells. Cell communication analysis revealed that overexpression of PAK2 promotes communication between cancer cells and the tumor microenvironment. Transcription factor activity prediction displayed the transcription factor network regulated by PAK2. Drug sensitivity analysis and metabolic analysis revealed the impact of PAK2 on gemcitabine resistance and metabolic pathways. CCK8 experiments showed that silencing PAK2 led to a decrease in the proliferative capacity of pancreatic cancer cells and scratch experiments demonstrated that low expression of PAK2 decreased invasion capability in pancreatic cancer cells. Flow cytometry reveals that PAK2 significantly inhibited apoptosis in pancreatic cancer cell lines. Molecules related to the TGF-beta pathway decreased with the inhibition of PAK2, and there were corresponding significant changes in molecules associated with EMT. PAK2 facilitated the angiogenic potential of cancer cells and promotes the epithelial-mesenchymal transition process by activating the TGF-beta signaling pathway. Simultaneously, it decreased the differentiation level of cancer cells, consequently enhancing their malignancy. Additionally, PAK2 fostered communication between cancer cells and the tumor microenvironment, augments cancer cell chemoresistance, and modulates energy metabolism pathways. In summary, PAK2 emerged as a pivotal gene orchestrating pancreatic cancer liver metastasis. Intervening in the expression of PAK2 may offer a promising therapeutic strategy for preventing liver metastasis of pancreatic cancer and improving its prognosis.

RBFOX2 deregulation promotes pancreatic cancer progression and metastasis through alternative splicing

RNA splicing is an important biological process associated with cancer initiation and progression. However, the contribution of alternative splicing to pancreatic cancer (PDAC) development is not well understood. Here, we identify an enrichment of RNA binding proteins (RBPs) involved in splicing regulation linked to PDAC progression from a forward genetic screen using Sleeping Beauty insertional mutagenesis in a mouse model of pancreatic cancer. We demonstrate downregulation of RBFOX2, an RBP of the FOX family, promotes pancreatic cancer progression and liver metastasis. Specifically, we show RBFOX2 regulates exon splicing events in transcripts encoding proteins involved in cytoskeletal remodeling programs. These exons are differentially spliced in PDAC patients, with enhanced exon skipping in the classical subtype for several RBFOX2 targets. RBFOX2 mediated splicing of ABI1, encoding the Abelson-interactor 1 adapter protein, controls the abundance and localization of ABI1 protein isoforms in pancreatic cancer cells and promotes the relocalization of ABI1 from the cytoplasm to the periphery of migrating cells. Using splice-switching antisense oligonucleotides (AONs) we demonstrate the ABI1 ∆Ex9 isoform enhances cell migration. Together, our data identify a role for RBFOX2 in promoting PDAC progression through alternative splicing regulation.

Discovery of a potent and highly selective inhibitor of SIRT6 against pancreatic cancer metastasis in vivo

Pancreatic cancer, one of the most aggressive malignancies, has no effective treatment due to the lack of targets and drugs related to tumour metastasis. SIRT6 can promote the migration of pancreatic cancer and could be a potential target for antimetastasis of pancreatic cancer. However, highly selective and potency SIRT6 inhibitor that can be used in vivo is yet to be discovered. Here, we developed a novel SIRT6 allosteric inhibitor, compound 11e, with maximal inhibitory potency and an IC50 value of 0.98 ± 0.13 μmol/L. Moreover, compound 11e exhibited significant selectivity against other histone deacetylases (HADC1‒11 and SIRT1‒3) at concentrations up to 100 μmol/L. The allosteric site and the molecular mechanism of inhibition were extensively elucidated by cocrystal complex structure and dynamic structural analyses. Importantly, we confirmed the antimetastatic function of such inhibitors in four pancreatic cancer cell lines as well as in two mouse models of pancreatic cancer liver metastasis. To our knowledge, this is the first study to reveal the in vivo effects of SIRT6 inhibitors on liver metastatic pancreatic cancer. It not only provides a promising lead compound for subsequent inhibitor development targeting SIRT6 but also provides a potential approach to address the challenge of metastasis in pancreatic cancer.

Netrin-1 feedforward mechanism promotes pancreatic cancer liver metastasis via hepatic stellate cell activation, retinoid, and ELF3 signaling

The biology of metastatic pancreatic ductal adenocarcinoma (PDAC) is distinct from that of the primary tumor due to changes in cell plasticity governed by a distinct transcriptome. Therapeutic strategies that target this distinct biology are needed. We detect an upregulation of the neuronal axon guidance molecule Netrin-1 in PDAC liver metastases that signals through its dependence receptor (DR), uncoordinated-5b (Unc5b), to facilitate metastasis invitro and invivo. The mechanism of Netrin-1 induction involves a feedforward loop whereby Netrin-1 on the surface of PDAC-secreted extracellular vesicles prepares the metastatic niche by inducing hepatic stellate cell activation and retinoic acid secretion that in turn upregulates Netrin-1 in disseminated tumor cells via RAR/RXR and Elf3 signaling. While this mechanism promotes PDAC liver metastasis, it also identifies a therapeutic vulnerability, as it can be targeted using anti-Netrin-1 therapy to inhibit metastasis using the Unc5b DR cell death mechanism.

Liver metastasis composed of pure squamous cell carcinoma component from pancreatic pure ductal adenocarcinoma: a case report

BackgroundLiver metastasis of pure squamous cell carcinoma (SCC) from pancreatic ductal adenocarcinoma has not been previously reported.Case presentationA 66-year-old man underwent a computed tomography scan 3 years after surgery for pancreatic head cancer, and the scan revealed a mass lesion in the right lobe of the liver. A liver tumor biopsy was performed, and SCC was diagnosed. Whole sections of the pancreatic head cancer were re-evaluated, but no areas of SCC-like differentiation were identified. Although the pathology differed between the pancreas and liver, metastasis of adenosquamous carcinoma was considered. Three courses of gemcitabine plus nab-paclitaxel were administered to treat the liver metastasis of pancreatic cancer, but no response was attained. Therefore, primary SCC of the liver was considered and hepatic resection was performed. The tumor had invaded the diaphragm, and S5/6 partial hepatic resection with right diaphragm resection was performed. Pathological examination showed pure SCC of the liver, which differed from the pancreatic cancer. KRAS mutations were evaluated in the pancreatic and liver tumor specimens, and Q61R mutation was identified in both specimens. This pure SCC of the liver was diagnosed as metastasis from pancreatic cancer not by histology but by genetic analysis.ConclusionsThis is the first reported case of pure SCC liver metastasis from pancreatic cancer without a squamous cell component in the primary tumor. Evaluation of KRAS mutations in both specimens was useful for diagnosis.

MRI with DWI improves detection of liver metastasis and selection of surgical candidates with pancreatic cancer: a systematic review and meta-analysis.

To perform a systematic review and meta-analysis to evaluate if magnetic resonance imaging (MRI) with diffusion weighted imaging (DWI) adds value compared to contrast-enhanced computed tomography (CECT) alone in the preoperative evaluation of pancreatic cancer. MEDLINE, EMBASE, and Cochrane databases were searched for relevant published studies through October 2022. Studies met eligibility criteria if they evaluated the per-patient diagnostic performance of MRI with DWI in the preoperative evaluation of newly diagnosed pancreatic cancer compared to CECT. Our primary outcome was the number needed to treat (NNT) to prevent one futile surgery using MRI with DWI, defined as those in which CECT was negative and MRI with DWI was positive for liver metastasis (i.e., surgical intervention in metastatic disease missed by CECT). The secondary outcomes were to determine the diagnostic performance and the NNT of MRI with DWI to change management in pancreatic cancer. Nine studies met the inclusion criteria with a total of 1121 patients, of whom 172 had liver metastasis (15.3%). The proportion of futile surgeries reduced by MRI with DWI was 6.0% (95% CI, 3.0-11.6%), yielding an NNT of 16.6. The proportion of cases that MRI with DWI changed management was 18.1% (95% CI, 9.9-30.7), corresponding to an NNT of 5.5. The per-patient sensitivity and specificity of MRI were 92.4% (95% CI, 87.4-95.6%) and 97.3% (95% CI, 96.0-98.1). MRI with DWI may prevent futile surgeries in pancreatic cancer by improving the detection of occult liver metastasis on preoperative CECT with an NNT of 16.6. MRI with DWI complements the standard preoperative CECT evaluation for liver metastasis in pancreatic cancer, improving the selection of surgical candidates and preventing unnecessary surgeries. • The NNT of MRI with DWI to prevent potential futile surgeries due to occult liver metastasis on CECT, defined as those in which CECT was negative and MRI with DWI was positive for liver metastasis, in patients with pancreatic cancer was 16.6. • The higher performance of MRI with DWI to detect liver metastasis occult on CECT can be attributed to an increased detection of subcentimeter liver metastasis.

Gut Streptococcus is a microbial marker for the occurrence and liver metastasis of pancreatic cancer.

Gut microbiome plays an indispensable role in the occurrence and progression in various diseases. The incidence of pancreatic cancer (PC) and liver metastasis (PCLM) are high, most of them are found in advanced stage. Therefore, it is particularly necessary to search for predictive biomarkers, which are helpful for early detection and treatment, and thus improve the survival rate and quality of life of PC patients. We retrospectively analyzed 44 pancreatic cancer patients (P group, n = 44) and 50 healthy people (N group, n = 50) from March 21, 2021 and August 2, 2022. Among all PC patients, we divided them into liver metastasis group (LM group, n = 27) and non-liver metastasis group (non-LM group, n = 17). DNA was extracted and 16S ribosomal RNA (16S rRNA) gene sequencing was performed. SPSS was used for statistical analyses and all bioinformatics analyses were based on QIIME2, p < 0.05 were considered statistically significant. The microbial richness and diversity of group P and LM were higher than that of group N and non-LM. LEfSe analysis found that Streptococcus was a significantly different microorganism, which was further identified by random forest (RF) model, and its ability to predict PC and PCLM was verified by ROC curve. We demonstrated significant differences in intestinal microbiome composition between PC patients and healthy people, and found that Streptococcus is a potential biomarker for early prediction of PC and PCLM, which is critical for early diagnosis of diseases.

Highly Selective Targeting of Pancreatic Cancer in the Liver with a Near-Infrared Anti-MUC5AC Probe in a PDOX Mouse Model: A Proof-of-Concept Study.

Accurately identifying metastatic disease is critical to directing the appropriate treatment in pancreatic cancer. Mucin 5AC is overexpressed in pancreatic cancer but absent in normal pancreas tissue. The present proof-of-concept study demonstrates the efficacy of an anti-mucin 5AC antibody conjugated to an IR800 dye (MUC5AC-IR800) to preferentially label a liver metastasis of pancreatic cancer (Panc Met) in a unique patient-derived orthotopic xenograft (PDOX) model. In orthotopic models, the mean tumor to background ratio was 1.787 (SD ± 0.336), and immunohistochemistry confirmed the expression of MUC5AC within tumor cells. MUC5AC-IR800 provides distinct visualization of pancreatic cancer liver metastasis in a PDOX mouse model, demonstrating its potential utility in staging laparoscopy and fluorescence-guided surgery.

Paired protein kinases PRKCI-RIPK2 promote pancreatic cancer growth and metastasis via enhancing NF-κB/JNK/ERK phosphorylation

BackgroundProtein kinases play a pivotal role in the malignant evolution of pancreatic cancer (PC) through mediating phosphorylation. Many kinase inhibitors have been developed and translated into clinical use, while the complex pathology of PC confounds their clinical efficacy and warrants the discovery of more effective therapeutic targets.MethodsHere, we used the Gene Expression Omnibus (GEO) database and protein kinase datasets to map the PC-related protein kinase-encoding genes. Then, applying Gene Expression and Profiling Interactive Analysis (GEPIA), GEO and Human Protein Atlas, we evaluated gene correlation, gene expression at protein and mRNA levels, as well as survival significance. In addition, we performed protein kinase RIPK2 knockout and overexpression to observe effects of its expression on PC cell proliferation, migration and invasion in vitro, as well as cell apoptosis, reactive oxygen species (ROS) production and autophagy. We established PC subcutaneous xenograft and liver metastasis models to investigate the effects of RIPK2 knockout on PC growth and metastasis. Co-immunoprecipitation and immunofluorescence were utilized to explore the interaction between protein kinases RIPK2 and PRKCI. Polymerase chain reaction and immunoblotting were used to evaluate gene expression and protein phosphorylation level.ResultsWe found fourteen kinases aberrantly expressed in human PC and nine kinases with prognosis significance. Among them, RIPK2 with both serine/threonine and tyrosine activities were validated to promote PC cells proliferation, migration and invasion. RIPK2 knockout could inhibit subcutaneous tumor growth and liver metastasis of PC. In addition, RIPK2 knockout suppressed autophagosome formation, increased ROS production and PC cell apoptosis. Importantly, another oncogenic kinase PRKCI could interact with RIPK2 to enhance the phosphorylation of downstream NF-κB, JNK and ERK.ConclusionPaired protein kinases PRKCI-RIPK2 with multiple phosphorylation activities represent a new pathological mechanism in PC and could provide potential targets for PC therapy.

ScRNA-Seq and imaging mass cytometry analyses unveil iNKT cells-mediated anti-tumor immunity in pancreatic cancer liver metastasis

Invariant natural killer T (iNKT) cells are innate-like T cells that are abundant in liver sinusoids and play a critical role in tumor immunity. However, the role of iNKT cells in pancreatic cancer liver metastasis (PCLM) has not been fully explored. In this study, we employed a hemi-spleen pancreatic tumor cell injection mouse model of PCLM, a model that closely mimics clinical conditions in humans, to explore the role of iNKT cells in PCLM. Activation of iNKT cells with α-galactosylceramide (αGC) markedly increased immune cell infiltration and suppressed PCLM progression. Via single cell RNA sequencing (scRNA-seq) we profiled over 30,000 immune cells from normal liver and PCLM with or without αGC treatment and were able to characterize the global changes of the immune cells in the tumor microenvironment upon αGC treatment, identifying a total of 12 subpopulations. Upon treatment with αGC, scRNA-Seq and flow cytometry analyses revealed increased cytotoxic activity of iNKT/NK cells and skewing CD4 T cells towards a cytotoxic Th1 profile and CD8 T cells towards a cytotoxic profile, characterized by higher proliferation and reduced exhaustion marker PD1 expression. Moreover, αGC treatment excluded tumor associated macrophages. Lastly, imaging mass cytometry analysis uncovered the reduced epithelial to mesenchymal transition related markers and increased active CD4 and CD8 T cells in PCLM with αGC treatment. Overall, our findings uncover the protective function of activated iNKT cells in pancreatic cancer liver metastasis through increased NK and T cell immunity and decreased tumor associated macrophages.

Nomograms for Predicting the Risk and Prognosis of Liver Metastases in Pancreatic Cancer: A Population-Based Analysis.

The liver is the most prevalent location of distant metastasis for pancreatic cancer (PC), which is highly aggressive. Pancreatic cancer with liver metastases (PCLM) patients have a poor prognosis. Furthermore, there is a lack of effective predictive tools for anticipating the diagnostic and prognostic techniques that are needed for the PCLM patients in current clinical work. Therefore, we aimed to construct two nomogram predictive models incorporating common clinical indicators to anticipate the risk factors and prognosis for PCLM patients. Clinicopathological information on pancreatic cancer that referred to patients who had been diagnosed between the years of 2004 and 2015 was extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate logistic regression analyses and a Cox regression analysis were utilized to recognize the independent risk variables and independent predictive factors for the PCLM patients, respectively. Using the independent risk as well as prognostic factors derived from the multivariate regression analysis, we constructed two novel nomogram models for predicting the risk and prognosis of PCLM patients. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve, the consistency index (C-index), and the calibration curve were then utilized to establish the accuracy of the nomograms' predictions and their discriminability between groups. Using a decision curve analysis (DCA), the clinical values of the two predictors were examined. Finally, we utilized Kaplan-Meier curves to examine the effects of different factors on the prognostic overall survival (OS). As many as 1898 PCLM patients were screened. The patient's sex, primary site, histopathological type, grade, T stage, N stage, bone metastases, lung metastases, tumor size, surgical resection, radiotherapy, and chemotherapy were all found to be independent risks variables for PCLM in a multivariate logistic regression analysis. Using a multivariate Cox regression analysis, we discovered that age, histopathological type, grade, bone metastasis, lung metastasis, tumor size, and surgery were all independent prognostic variables for PCLM. According to these factors, two nomogram models were developed to anticipate the prognostic OS as well as the risk variables for the progression of PCLM in PCLM patients, and a web-based version of the prediction model was constructed. The diagnostic nomogram model had a C-index of 0.884 (95% CI: 0.876-0.892); the prognostic model had a C-index of 0.686 (95% CI: 0.648-0.722) in the training cohort and a C-index of 0.705 (95% CI: 0.647-0.758) in the validation cohort. Subsequent AUC, calibration curve, and DCA analyses revealed that the risk and predictive model of PCLM had high accuracy as well as efficacy for clinical application. The nomograms constructed can effectively predict risk and prognosis factors in PCLM patients, which facilitates personalized clinical decision-making for patients.

Identification of EMT-related alternative splicing event of TMC7 to promote invasion and migration of pancreatic cancer.

Epithelial-to-mesenchymal transition (EMT) is tightly associated with the invasion and metastasis of pancreatic cancer with rapid progression and poor prognosis. Notably, gene alternative splicing (AS) event plays a critical role in regulating the progression of pancreatic cancer. Therefore, this study aims to identify the EMT-related AS event in pancreatic cancer. The EMT-related gene sets, transcriptomes, and matched clinical data were obtained from the MSigDB, The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC), and Gene Expression Omnibus (GEO) databases. Key gene AS events associated with liver metastasis were identified by prognostic analysis, gene set variation analysis (GSVA), and correlation analysis in pancreatic cancer. The cell line and organoid model was constructed to evaluate these key gene AS events in regulating pancreatic cancer in vitro. Furthermore, we established an EMT-related gene set consisting of 13 genes by prognostic analysis, the role of which was validated in two other databases. Finally, the human pancreatic cancer tissue and organoid model was used to evaluate the correlation between the enrichment of this gene set and liver metastasis. Prognostic analysis and correlation analysis revealed that eight AS events were closely associated with the prognosis of pancreatic cancer. Furthermore, the expression of TMC7 and CHECK1 AS events was increased in the metastatic lesions of the human tissue and organoid model. Additionally, the knockdown of exon 17 of TMC7 significantly inhibited the proliferation, invasion, and migration of pancreatic cancer cells in 2D and 3D cell experiments. Finally, the expression of exon 17 of TMC17 exhibited a significant correlation with the poor prognosis in pancreatic ductal adenocarcinoma (PDAC). The AS events of TMC7 and CHECK1 were associated with liver metastasis in pancreatic cancer. Moreover, exon 17 of TMC7 could be a potential therapeutic target in pancreatic cancer.