Therapeutic Target For Pancreatic Cancer Research Articles

MicroRNAs: emerging biomarkers and therapeutic targets in pancreatic cancer

Pancreatic cancer (PC) is a highly malignant disease with high aggressiveness and a dismal prognosis, which is challenging to diagnose clinically early and gains low benefit from standard therapies. MicroRNAs (miRNAs) have become a hot topic in oncology research. Current evidence indicates that miRNAs are regulators involved in the entire process of PC, providing new diagnostic and therapeutic strategies for this fatal disease. Related research has been rapidly updated, making it necessary to review it to propose new directions and ideas and provide guidance for the development of precision medicine for PC. We reviewed the relevant literature through Pubmed, Embase, Web of Science and Medline, showing that abnormally expressed miRNAs in PC patients have the potential to be used as biomarkers for diagnosis and prognosis, highlighting the excellent prospect of combining miRNAs with traditional therapies, and the effective application of these factors for PC, especially miRNA mimics and inhibitors. MiRNAs participate in the entire process of PC and play important roles in diagnosis, treatment and prognosis. They are potential factors in conquering PC in the future.

Integrating plasma protein-centric multi-omics to identify potential therapeutic targets for pancreatic cancer

BackgroundDeciphering the role of plasma proteins in pancreatic cancer (PC) susceptibility can aid in identifying novel targets for diagnosis and treatment.MethodsWe examined the relationship between genetically determined levels of plasma proteins and PC through a systemic proteome-wide Mendelian randomization (MR) analysis utilizing cis-pQTLs from multiple centers. Rigorous sensitivity analyses, colocalization, reverse MR, replications with varying instrumental variable selections and additional datasets, as well as subsequent meta-analysis, were utilized to confirm the robustness of significant findings. The causative effect of corresponding protein-coding genes’ expression and their expression pattern in single-cell types were then investigated. Enrichment analysis, between-protein interaction and causation, knock-out mice models, and mediation analysis with established PC risk factors were applied to indicate the pathogenetic pathways. These candidate targets were ultimately prioritized upon druggability and potential side effects predicted by a phenome-wide MR.ResultsTwenty-one PC-related circulating proteins were identified in the exploratory phase with no evidence for horizontal pleiotropy or reverse causation. Of these, 11 were confirmed in a meta-analysis integrating external validations. The causality at a transcription level was repeated for neutrophil elastase, hydroxyacylglutathione hydrolase, lipase member N, protein disulfide-isomerase A5, xyloside xylosyltransferase 1. The carbohydrate sulfotransferase 11 and histo-blood group ABO system transferase exhibited high-support genetic colocalization evidence and were found to affect PC carcinogenesis partially through modulating body mass index and type 2 diabetes, respectively. Approved drugs have been established for eight candidate targets, which could potentially be repurposed for PC therapies. The phenome-wide investigation revealed 12 proteins associated with 51 non-PC traits, and interference on protein disulfide-isomerase A5 and cystatin-D would increase the risk of other malignancies.ConclusionsBy employing comprehensive methodologies, this study demonstrated a genetic predisposition linking 21 circulating proteins to PC risk. Our findings shed new light on the PC etiology and highlighted potential targets as priorities for future efforts in early diagnosis and therapeutic strategies of PC.

Long non-coding RNA LINC00930 targeting miR-6792-3p/ZBTB16 regulates the proliferation and EMT of pancreatic cancer

Emerging evidence suggests the dysregulation of long non-coding RNAs (lncRNAs) involved in pancreatic cancer (PC). However, the function of LINC00930 in PC has not been elaborated. In this study, we found that LINC00930 was significantly down-regulated in PC cell lines and tissues, and associated with tumor size, lymphatic metastasis, TNM stage and poor prognosis. According to the bioinformatics database, the downregulation of LINC00930 was a common event in PC associated with prognosis and EMT. Overexpression of LINC00930 inhibited the aggressive cancer phenotypes including proliferation, metastasis and epithelial-mesenchymal transition (EMT) of PC in vitro and in vivo. Bioinformatics and dual-luciferase reporter assay indicated that miR-6792-3p could directly bind to LINC00930. Additionally, the Zinc finger and BTB domain containing 16 (ZBTB16) was significantly declined in PC, which was predicted to be the downstream gene of miR-6792-3p. MiR-6792-3p mimic rescued the decreased proliferation, metastasis and EMT caused by ZBTB16 in PC cells. The LINC00930/miR-6792-3p/ZBTB16 axis was associated with the malignant progression and process of PC. The relative expression of LINC00930 was negatively correlated with the expression of miR-6792-3p and was closely linked with ZBTB16 levels in PC. LINC00930 might serve as a potential prognostic biomarker and therapeutic target for PC.

HHLA2 deficiency inhibits pancreatic cancer progression and THP-1 macrophage M2 polarization via EGFR/MAPK/ERK and mTOR/AKT pathway

BackgroundHuman endogenous retrovirus subfamily H long terminal repeat associating protein 2, (HHLA2), a member of B7 family, exhibits heightened expression in various malignant tumors. However, the exact functions of HHLA2 in pancreatic cancer (PC) remain incompletely elucidated.MethodsWe initially conducted an analysis of the B7 family members’ expression pattern in pancreatic tumor samples and adjacent normal tissues using The Cancer Genome Atlas (TCGA) database. Subsequently, immunohistochemistry, RT-qPCR and western blot methods were used to assess HHLA2 expression levels in PC tissues and cell lines. Furthermore, after silencing HHLA2 in PC cell lines, cell migration and proliferation of PC cells were detected by wound healing and CCK-8 assays, and cell invasion of PC cells was detected by transwell assays. We also investigated the regulation of epithelial-mesenchymal transition (EMT) markers and levels of EGFR, MEK, ERK1/2, mTOR and AKT via western blot analysis. Finally, the correlation between HHLA2 expression and immune infiltration was further explored.ResultsSilencing of HHLA2 resulted in the inhibition of PC cell proliferation, migration and invasion, potentially through the suppression of the EGFR/MAPK/ERK and mTOR/AKT signaling pathway. Additionally, silencing HHLA2 led to the inhibition of M2-type polarization of tumor associated macrophages (TAMs).ConclusionThe knockdown of HHLA2 was observed to inhibit the migration and invasion of PC cells through the regulation of the EMT process and EGFR/MAPK/ERK and mTOR/AKT pathway. Furthermore, silencing HHLA2 was found to modulate M2 polarization of TAMs. These finding suggest that HHLA2 could be a promising therapeutic target for Pancreatic cancer.

Identification of biomarkers and potential therapeutic targets for pancreatic cancer by proteomic analysis in two prospective cohorts

Pancreatic cancer (PC) is the deadliest malignancy due to late diagnosis. Aberrant alterations in the blood proteome might serve as biomarkers to facilitate early detection of PC. We designed a nested case-control study of incident PC based on a prospective cohort of 38,295 elderly Chinese participants with ∼5.7 years' follow-up. Forty matched case-control pairs passed the quality controls for the proximity extension assay of 1,463 serum proteins. With a lenient threshold of p<0.005, we discovered regenerating family member 1A (REG1A), REG1B, tumor necrosis factor (TNF), and phospholipase A2 group IB (PLA2G1B) in association with incident PC, among which the two REG1 proteins were replicated using the UK Biobank Pharma Proteomics Project, with effect sizes increasing steadily as diagnosis time approaches the baseline. Mendelian randomization analysis further supported the potential causal effects of REG1 proteins on PC. Taken together, circulating REG1A and REG1B are promising biomarkers and potential therapeutic targets for the early detection and prevention of PC.

Differentially expressed genes associated with high metabolic tumor volume served as diagnostic markers and potential therapeutic targets for pancreatic cancer

BackgroundThe lack of distinct biomarkers for pancreatic cancer is a major cause of early-stage detection difficulty. The pancreatic cancer patient group with high metabolic tumor volume (MTV), one of the values measured from positron emission tomography—a confirmatory method and standard care for pancreatic cancer, showed a poorer prognosis than those with low MTV. Therefore, MTV-associated differentially expressed genes (DEGs) may be candidates for distinctive markers for pancreatic cancer. This study aimed to evaluate the possibility of MTV-related DEGs as markers or therapeutic targets for pancreatic cancer.MethodsTumor tissues and their normal counterparts were obtained from patients undergoing preoperative 18F-FDG PET/CT. The tissues were classified into MTV-low and MTV-high groups (7 for each) based on the MTV2.5 value of 4.5 (MTV-low: MTV2.5 < 4.5, MTV-high: MTV2.5 ≥ 4.5). Gene expression fold change was first calculated in cancer tissue compared to its normal counter and then compared between low and high MTV groups to obtain significant DEGs. To assess the suitability of the DEGs for clinical application, the correlation of the DEGs with tumor grades and clinical outcomes was analyzed in TCGA-PAAD, a large dataset without MTV information.ResultsTotal RNA-sequencing (MTV RNA-Seq) revealed that 44 genes were upregulated and 56 were downregulated in the high MTV group. We selected the 29 genes matching MTV RNA-seq patterns in the TCGA-PAAD dataset, a large clinical dataset without MTV information, as MTV-associated genes (MAGs). In the analysis with the TCGA dataset, MAGs were significantly associated with patient survival, treatment outcomes, TCGA-PAAD-suggested markers, and CEACAM family proteins. Some MAGs showed an inverse correlation with miRNAs and were confirmed to be differentially expressed between normal and cancerous pancreatic tissues. Overexpression of KIF11 and RCC1 and underexpression of ADCY1 and SDK1 were detected in ~ 60% of grade 2 pancreatic cancer patients and associated with ~ 60% mortality in stages I and II.ConclusionsMAGs may serve as diagnostic markers and miRNA therapeutic targets for pancreatic cancer. Among the MAGs, KIF11, RCC1, ADCY, and SDK1 may be early diagnostic markers.

TAGLN2 targeted control of ARPC5-mediated activation of the MEK/ERK signaling pathway influences the proliferation, invasion, and metastasis of pancreatic cancer cells

PurposePcancreatic cancer (PC) is a common tumor of the digestive tract with an insidious onset and high malignancy potential. Currently, surgery is the only effective treatment modality. Therefore, it is crucial to discover new targeted therapeutic modalities. We studied whether transgelin 2 (TAGLN2) targeted control of actin-related protein 2/3 complex subunit 5 (ARPC5)-mediated activation of the MEK/ERK signaling pathway to Influences the proliferation, invasion, and metastasis of pancreatic cancer cells. MethodsThe effects of TAGLN2 overexpression and knockdown on the proliferative viability and invasive metastatic ability of pancreatic cancer cells were verified through in vitro and in vivo assays via constructing a stable lentiviral transfection of human pancreatic cancer cell lines PANC-1 and SW1990. Bioinformatics analysis was used to predict the relationship between TAGLN2 and ARPC5. These findings were subsequently verified through protein profiling, immunofluorescence (IF), and coimmunoprecipitation (CO-IP) assays. In vitro experiments were also conducted to confirm the effect of TAGLN2 modulation on ARPC5 expression, which subsequently affects the proliferation and invasive metastatic ability of pancreatic cancer cells. The study analyzed the relationship between TAGLN2 and the MEK/ERK signaling pathway through bioinformatics and in vitro experiments with the MEK signaling pathway inhibitor U0126. ResultsTAGLN2 is expressed at high levels in pancreatic cancer cell lines, and its expression is positively correlated with poor prognosis of pancreatic cancer. ARPC5 is a direct target of TAGLN2 and is associated with the MEK/ERK signaling pathway. In vivo and ex vivo experiments confirmed that overexpression of TAGLN2 promoted the proliferation, invasion, and metastasis of pancreatic cancer cells, and silencing ARPC5 reversed these effect. ConclusionOur research revealed that TAGLN2 protein binds to ARPC5 protein and contributes to increased ARPC5 expression and activation of the MEK/ERK signaling pathway. This activation promotes pancreatic cancer cell growth, infiltration, and spread. Hence, TAGLN2 is a potential viable therapeutic target in pancreatic cancer and represents a novel therapeutic approach.

Potential clinical applications of extracellular vesicles in pancreatic cancer: exploring untapped opportunities from biomarkers to novel therapeutic approaches

Pancreatic cancer is a highly lethal and metastatic malignancy, mainly because it often remains undetected until advanced stages due to the limitations of current diagnostic methods, rendering currently available therapies ineffective. Therefore, it is imperative to identify useful biomarkers for early diagnosis and new therapeutic targets for pancreatic cancer. Recently, extracellular vesicles have emerged as promising biomarkers for the diagnosis and prognosis of pancreatic cancer. Given their presence in various bodily fluids, extracellular vesicles offer a non-invasive approach through liquid biopsy to detect and monitor cancer progression. In this review, we comprehensively examine the multifaceted roles of extracellular vesicles in the progression of cancer, while also exploring their potential as diagnostic, prognostic, and therapeutic biomarkers in the context of pancreatic cancer.

Multi-omics pan-cancer study of SPTBN2 and its value as a potential therapeutic target in pancreatic cancer

SPTBN2 is a protein-coding gene that is closely related to the development of malignant tumors. However, its prognostic value and biological function in pan-cancer, especially pancreatic cancer (PAAD), have not been reported. In the present study, a novel exploration of the value and potential mechanism of SPTBN2 in PAAD was conducted using multi-omics in the background of pan-cancer. Via various database analysis, up-regulated expression of SPTBN2 was detected in most of the tumor tissues examined. Overexpression of SPTBN2 in PAAD and kidney renal clear cell cancer patients potentially affected overall survival, disease-specific survival, and progression-free interval. In PAAD, SPTBN2 can be used as an independent factor affecting prognosis. Mutations and amplification of SPTBN2 were detected, with abnormal methylation of SPTBN2 affecting its expression and the survival outcome of PAAD patients. Immunoassay results demonstrate that SPTBN2 was a potential biomarker for predicting therapeutic response in PAAD, and may influence the immunotherapy efficacy of PAAD by regulating levels of CD8 + T cells and neutrophil infiltration. Results from an enrichment analysis indicated that SPTBN2 may regulate the development of PAAD via immune pathways. Thus, SPTBN2 is a potential prognostic biomarker and immunotherapy target based on its crucial role in the development of PAAD.

The clinical significance and oncogenic function of LRRFIP1 in pancreatic cancer

PurposePancreatic cancer is a lethal malignancy with a grim prognosis. Previous studies have proven that Leucine Rich Repeat of Flightless-1 Interacting Protein 1 (LRRFIP1) plays a pivotal role in cell biological processes, while its clinical significance and function in pancreatic cancer remain to be elucidated. Hence, we aimed to explore the roles and mechanisms of LRRFIP1 in pancreatic cancer.MethodsThe expression of LRRFIP1 in pancreatic cancer tissues and its clinical significance for pancreatic cancer were analyzed by immunohistochemistry assay and bioinformatic analysis. The influences of LRRFIP1 on the proliferation and migration of pancreatic cancer cells were assessed in vitro. The underlying mechanisms of LRRFIP1 in pancreatic cancer progression were explored using gene set enrichment analysis (GSEA) and molecular experiments.ResultsThe results showed that LRRFIP1 expression was significantly upregulated in pancreatic cancer tissues compared to the normal tissues, and such upregulation was associated with poor prognosis of patients with pancreatic cancer. GSEA revealed that LRRFIP1 upregulation was significantly associated with various cancer-associated signaling pathways, including PI3K/AKT signaling pathway and Wnt pathway. Furthermore, LRRFIP1 was found to be associated with the infiltration of various immune cells. Functionally, LRRFIP1 silencing suppressed cell proliferation somewhat and inhibited migration substantially. Further molecular experiments indicated that LRRFIP1 silencing inactivated the AKT/GSK-3β/β-catenin signaling axis.ConclusionTaken together, LRRFIP1 is associated with tumorigenesis, immune cell infiltration, and prognosis in pancreatic cancer, which suggests that LRRFIP1 may be a potential biomarker and therapeutic target for pancreatic cancer.

Identification of fibronectin type III domain containing 3B as a potential prognostic and therapeutic target for pancreatic cancer: a preliminary analysis

BackgroundFibronectin type III domain containing 3B (FNDC3B), a member of the fibronectin type III domain-containing protein family, has been indicated in various malignancies. However, the precise role of FNDC3B in the progression of pancreatic cancer (PC) still remains to be elucidated.MethodsIn this study, we integrated data from the National Center for Biotechnology Information, the Cancer Genome Atlas, Genotype-Tissue Expression database, and Gene Expression Omnibus datasets to analyze FNDC3B expression and its association with various clinicopathological parameters. Subsequently, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, along with Gene Set Enrichment Analysis (GSEA), single sample Gene Set Enrichment Analysis (ssGSEA) and estimate analysis were recruited to delve into the biological function and immune infiltration based on FNDC3B expression. Additionally, the prognostic estimation was conducted using Cox analysis and Kaplan–Meier analysis. Subsequently, a nomogram was constructed according to the result of Cox analysis to enhance the prognostic ability of FNDC3B. Finally, the preliminary biological function of FNDC3B in PC cells was explored.ResultsThe study demonstrated a significantly higher expression of FNDC3B in tumor tissues compared to normal pancreatic tissues, and this expression was significantly associated with various clinicopathological parameters. GSEA revealed the involvement of FNDC3B in biological processes and signaling pathways related to integrin signaling pathway and cell adhesion. Additionally, ssGSEA analysis indicated a positive correlation between FNDC3B expression and infiltration of Th2 cells and neutrophils, while showing a negative correlation with plasmacytoid dendritic cells and Th17 cells infiltration. Kaplan–Meier analysis further supported that high FNDC3B expression in PC patients was linked to shorter overall survival, disease-specific survival, and progression-free interval. However, although univariate analysis demonstrated a significant correlation between FNDC3B expression and prognosis in PC patients, this association did not hold true in multivariate analysis. Finally, our findings highlight the crucial role of FNDC3B expression in regulating proliferation, migration, and invasion abilities of PC cells.ConclusionDespite limitations, the findings of this study underscored the potential of FNDC3B as a prognostic biomarker and its pivotal role in driving the progression of PC, particularly in orchestrating immune responses.

Hsa_circ_0007919 promotes pancreatic cancer metastasis by modulating Sp1-mediated THBS1 transcription.

CircRNAs are abnormally expressed in various cancers and play an important role in the occurrence and development of cancers. However, their biological functions and the underlying molecular mechanisms in pancreatic cancer (PC) metastasis are incompletely understood. Differentially expressed circRNAs were identified by second-generation transcriptome sequencing in three pairs of PC tissues and adjacent tissues. The expression and prognostic significance of hsa_circ_0007919 were evaluated by qRT-PCR and Kaplan-Meier survival curves. Gain- and loss-of-function assays were conducted to detect the role of hsa_circ_0007919 in PC metastasis invitro. A lung metastasis model and IHC experiments were conducted to confirm the effects of hsa_circ_0007919 on tumor metastasis invivo. Mechanistically, RNA immunoprecipitation and chromatin immunoprecipitation assays were conducted to explore the interplay among hsa_circ_0007919, Sp1, and the THBS1 promoter. hsa_circ_0007919 was significantly upregulated in PC tissues and cells and was correlated with lymph node metastasis, TNM stage, and poor prognosis. Knockdown of hsa_circ_0007919 significantly suppressed the migration and invasion of PC cells invitro and inhibited tumor metastasis invivo. However, overexpression of hsa_circ_0007919 exerted the opposite effects. Mechanistically, hsa_circ_0007919 could recruit the transcription factor Sp1 to inhibit THBS1 transcription, thereby facilitating PC metastasis. hsa_circ_0007919 can promote the metastasis of PC by inhibiting THBS1 expression. hsa_circ_0007919 may be a potential therapeutic target in PC.

Emerging potential value of long non-coding RNAs as biomarkers and therapeutic targets in pancreatic cancer

Emerging potential value of long non-coding RNAs as biomarkers and therapeutic targets in pancreatic cancer

IFIT1 modulates the proliferation, migration and invasion of pancreatic cancer cells via Wnt/β-catenin signaling.

Previously, Interferon-induced Protein with Tetratricopeptide Repeats 1 (IFIT1) has been shown to promote cancer development. Here, we aimed to explore the role of IFIT1 in the development and progression of pancreatic cancer, including the underlying mechanisms. We explored IFIT1 expression in pancreatic cancer samples using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. Cell Counting Kit-8 (CCK8), colony formation, scratch wound-healing and Transwell assays were performed to assess the proliferation, migration and invasion abilities of pancreatic cancer cells. Gene Set Enrichment Analysis (GSEA) and Western blotting were performed to assess the regulatory effect of IFIT1 on the Wnt/β-catenin pathway. We found that upregulation of IFIT1 expression is common in pancreatic cancer and is negatively associated with overall patient survival. Knockdown of IFIT1 expression led to decreased proliferation, migration and invasion of pancreatic cancer cells. We also found that IFIT1 could regulate Wnt/β-catenin signaling, and that a Wnt/β-catenin agonist could reverse this effect. In addition, we found that IFIT1 can promote epithelial-mesenchymal transition (EMT) of pancreatic cancer cells. Our data indicate that IFIT1 increases pancreatic cancer cell proliferation, migration and invasion by activating the Wnt/β-catenin pathway. In addition, we found that EMT could be regulated by IFIT1. IFIT1 may serve as a potential therapeutic target for pancreatic cancer.

Abstract 4588: Combination of MTA-cooperative PRMT5 inhibitor and direct mutant-selective KRAS inhibitors as a novel therapeutic approach for MTAP-deficient pancreatic cancer

Abstract KRAS is mutationally activated in 95% of pancreatic ductal adenocarcinoma (PDAC) patients. Direct KRAS inhibitors are under intense preclinical and clinical development, with two KRASG12C mutant-selective inhibitors (G12Ci) now approved. However, treatment-associated resistance to KRAS inhibitors has been reported in the clinic highlighting an urgent need to identify both additional therapeutic targets and novel combination treatment strategies with KRAS inhibitors. To that end, we performed a CRISPR/Cas9 loss-of-function screen using a library targeting ~2,500 druggable genes in KRASG12C/D-mutant PDAC cell lines. We identified multiple genes that were essential for PDAC cell growth and selected PRMT5, a protein arginine methyltransferase, to assess as a novel therapeutic target for pancreatic cancer. We found that suppression of PRMT5 activity using two distinct first-generation clinical candidate small molecule inhibitors (JNJ-64619178 and GSK3326595) demonstrated single agent activity and reduced PDAC cell growth. We further assessed a mechanistically distinct MTA-cooperative clinical candidate PRMT5 inhibitor, MRTX1719, that is selective for MTAP-deleted tumors, which occur in ~25% of PDAC patients. We determined that MRTX1719 exhibited low nanomolar GI50 activities in MTAP-deficient but not MTAP wild-type KRAS-mutant cell lines. Unexpectedly, PDAC cells treated with MRTX1719 exhibited a paradoxical activation of ERK, suggesting that combined inhibition of PRMT5 and KRAS might be therapeutically advantageous. In support of our hypothesis, we demonstrated that combination treatment with MRTX1719 and mutant selective KRAS inhibitors (G12Ci/MRTX849 and G12Di/MRTX1133) further sensitized KRASG12C/D-mutant PDAC cells to KRAS inhibition in short- and long-term growth assays as well as in vivo xenograft studies. Our ongoing studies are evaluating the consequences of co-targeting PRMT5 and KRAS on gene expression changes using RNA-Seq and cancer cell signaling pathways using RPPA analyses. In summary, our data support concurrent inhibition of PRMT5 and KRAS as a promising therapeutic strategy for MTAP-deficient KRAS-mutant pancreatic cancer. Citation Format: Kristina Drizyte-Miller, Wen-Hsuan Chang, Andrew M. Waters, Clint A. Stalnecker, Junning Wang, Andrew J. Aguirre, Adrienne D. Cox, Channing J. Der. Combination of MTA-cooperative PRMT5 inhibitor and direct mutant-selective KRAS inhibitors as a novel therapeutic approach for MTAP-deficient 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 4588.

Abstract 455: Identification of hsa-miR-6794-3p as a key regulatory factor in human pancreatic cancer metastasis

Abstract Metastasis is a major factor in treatment failure in patients with pancreatic cancer, but the underlying mechanisms remain unclear, and new, effective treatment strategies are needed. Here, we sought to identify novel microRNAs (miRNAs) with a key role in pancreatic cancer metastasis. Using a microarray analysis to evaluate miRNA expression in metastatic and non-metastatic pancreatic cancer, we found that expression of the miRNA, hsa-miR-6794-3p, was significantly lower in metastatic pancreatic cancer tissues than in non-metastatic pancreatic cancer tissues. Methylation-specific polymerase chain reaction analyses revealed that hsa-miR-6794-3p expression was downregulated in metastatic pancreatic cancer cells by hypermethylation of CpG islands within the hsa-miR-6794-3p promoter. Gain- and loss-of-function approaches using the human pancreatic cancer cell lines, MIA-PaCa-2 and HPAF-II, expressing low and high levels of hsa-miR-6794-3p, respectively, suggested a role for hsa-miR-6794-3p in decreasing cell invasion, migration, and epithelial-mesenchymal transition (EMT) signaling. Notably, we found that hsa-miR-6794-3p exerts its effects by inhibiting expression of the chromatin remodeling factor, RBBP4, through direct binding to the 3’-untranslated region of its mRNA. The resulting suppression of RBBP4 expression increases levels of the transcription factor GRHL2, which is involved in regulating invasion, migration, and EMT signaling in metastatic pancreatic cancer cells. Thus, lower levels of hsa-miR-6794-3p disrupt GRHL2-mediated regulation of these pathways by disinhibiting expression of the GRHL2 negative regulator, RBBP4. Consistent with these findings, an investigation of the relationship between hsa-miR-6794-3p and clinicopathological features in pancreatic cancer patients using publicly available datasets and immunohistochemistry showed that low levels of hsa-miR-6794-3p are correlated with a poorer prognosis in pancreatic cancer patients. Additional preclinical experiments in nude mice clearly demonstrated that hsa-miR-6794-3p is capable of suppressing pancreatic cancer cell metastasis. Taken together, these results suggest that hsa-miR-6794-3p suppresses tumor metastasis and thus represents a promising prognostic biomarker and therapeutic target in pancreatic cancer. Citation Format: Ha Gyeong Kim, Eun-Taex Oh, Yunmi Cho, Heon Joo Park. Identification of hsa-miR-6794-3p as a key regulatory factor in human pancreatic 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 455.

CCNI2 promotes pancreatic cancer through PI3K/AKT signaling pathway.

Globally, pancreatic cancer is recognized as one of the deadliest malignancies that lacks effective targeted therapies. This study aims to explore the role of cyclin I-like protein (CCNI2), a homolog of cyclin I (CCNI), in the progression of pancreatic cancer, thereby providing a theoretical basis for its treatment. Firstly, the expression of CCNI2 in pancreatic cancer tissues was determined through immunohistochemical staining. The biological role of CCNI2 in pancreatic cancer cells was further assessed using both in vitro and in vivo loss/gain-of-function assays. Our data revealed that CCNI2 expression was abnormally elevated in pancreatic cancer, and clinically, increased CCNI2 expression generally correlated with reduced overall survival. Functionally, CCNI2 contributed to the malignant progression of pancreatic cancer by promoting the proliferation and migration of tumor cells. Consistently, in vivo experiments verified that CCNI2 knockdown impaired the tumorigenic ability of pancreatic cancer cells. Moreover, the addition of phosphatidylinositol 3-kinase (PI3K) inhibitors could partially reverse the promoting effect of CCNI2 on the malignant phenotypes of pancreatic cancer cells. CCNI2 promoted pancreatic cancer through PI3K/protein kinase B (AKT) signaling pathway, indicating its potential as a prognostic marker and therapeutic target for pancreatic cancer.

TiRNA-Val-CAC-2 interacts with FUBP1 to promote pancreatic cancer metastasis by activating c‑MYC transcription

Cumulative studies have established the significance of transfer RNA-derived small RNA (tsRNA) in tumorigenesis and progression. Nevertheless, its function and mechanism in pancreatic cancer metastasis remain largely unclear. Here, we screened and identified tiRNA-Val-CAC-2 as highly expressed in pancreatic cancer metastasis samples by tsRNA sequencing. We also observed elevated levels of tiRNA-Val-CAC-2 in the serum of pancreatic cancer patients who developed metastasis, and patients with high levels of tiRNA-Val-CAC-2 exhibited a worse prognosis. Additionally, knockdown of tiRNA-Val-CAC-2 inhibited the metastasis of pancreatic cancer in vivo and in vitro, while overexpression of tiRNA-Val-CAC-2 promoted the metastasis of pancreatic cancer. Mechanically, we discovered that tiRNA-Val-CAC-2 interacts with FUBP1, leading to enhanced stability of FUBP1 protein and increased FUBP1 enrichment in the c-MYC promoter region, thereby boosting the transcription of c-MYC. Of note, rescue experiments confirmed that tiRNA-Val-CAC-2 could influence pancreatic cancer metastasis via FUBP1-mediated c-MYC transcription. These findings highlight a potential novel mechanism underlying pancreatic cancer metastasis, and suggest that both tiRNA-Val-CAC-2 and FUBP1 could serve as promising prognostic biomarkers and potential therapeutic targets for pancreatic cancer.

The TGF-β superfamily as potential therapeutic targets in pancreatic cancer.

The transforming growth factor (TGF)-β superfamily has important physiologic roles and is dysregulated in many pathologic processes, including pancreatic cancer. Pancreatic cancer is one of the most lethal cancer diagnoses, and current therapies are largely ineffective due to tumor resistance and late-stage diagnosis with poor prognosis. Recent efforts are focused on the potential of immunotherapies in improving therapeutic results for patients with pancreatic cancer, among which TGF-β has been identified as a promising target. This review focuses on the role of TGF-β in the diseased pancreas and pancreatic cancer. It also aims to summarize the current status of therapies targeting the TGF-β superfamily and postulate potential future directions in targeting the TGF-β signaling pathways.

MICAL2 implies immunosuppressive features and acts as an independent and adverse prognostic biomarker in pancreatic cancer

At present, clinical outcomes of pancreatic cancer patients are still poor. New therapeutic targets for pancreatic cancer are urgently needed. Previous studies have indicated that Microtubule Associated Monooxygenase, Calponin and LIM Domain Containing 2 (MICAL2) is highly expressed in many tumors and promotes tumor progression. However, the role played by MICAL2 in pancreatic cancer remains unclear. Based on gene expression and clinical information from multiple datasets, we used comprehensive bioinformatics analysis in combination with tissue microarray to explore the function and clinical value of MICAL2. The results showed that MICAL2 was highly expressed in pancreatic cancer tissue and exhibited potential diagnostic capability. High expression of MICAL2 was also associated with poor prognosis and acted as an independent prognostic factor. MICAL2, mainly expressed in fibroblasts of pancreatic cancer, was closely related to metastasis and immune-related features, such as epithelial-mesenchymal transformation, extracellular cell matrix degradation, and inflammatory response. Furthermore, higher MICAL2 expression in pancreatic cancer was also associated with an increase in cancer-associated fibroblasts as well as M2 macrophage infiltration, and a reduction in CD8 + T cell infiltration, thereby facilitating the formation of an immunosuppressive microenvironment. Our results helped elucidate the clinical value and function in metastasis and immunity of MICAL2 in pancreatic cancer. These findings provided potential clinical strategies for diagnosis, targeted therapy combination immunotherapy, and prognosis in patients with pancreatic cancer.