Triptolide enhances TRAIL sensitivity of pancreatic cancer cells by activating autophagy via downregulation of PUM1

Antitumor mechanisms and future clinical applications of the natural product triptolide

Triptolide (TPL) is a compound sourced from Tripterygium wilfordii Hook. F., a traditional Chinese medicinal herb recognized for its impressive anti-inflammatory, anti-angiogenic, immunosuppressive, and antitumor qualities. Notwithstanding its favorable attributes, the precise mechanism through which TPL influences tumor cells remains enigmatic. Its toxicity and limited water solubility significantly impede the clinical application of TPL. We offer a comprehensive overview of recent research endeavors aimed at unraveling the antitumor mechanism of TPL in this review. Additionally, we briefly discuss current strategies to effectively manage the challenges associated with TPL in future clinical applications. By compiling this information, we aim to enhance the understanding of the underlying mechanisms involved in TPL and identify potential avenues for further advancement in antitumor therapy.

Advances in the treatment of pancreatic cancer with traditional Chinese medicine

Pancreatic cancer is a common malignancy of the digestive system. With a high degree of malignancy and poor prognosis, it is called the "king of cancers." Currently, Western medicine treats pancreatic cancer mainly by surgical resection, radiotherapy, and chemotherapy. However, the curative effect is not satisfactory. The application of Traditional Chinese Medicine (TCM) in the treatment of pancreatic cancer has many advantages and is becoming an important facet of comprehensive clinical treatment. In this paper, we review current therapeutic approaches for pancreatic cancer. We also review the protective effects shown by TCM in different models and discuss the potential molecular mechanisms of these.

A bioinformatics analysis, pre-clinical and clinical conception of autophagy in pancreatic cancer: Complexity and simplicity in crosstalk

Pancreatic cancer (PC) is a serious gastrointestinal tract disease for which the 5-year survival rate is less than 10%, even in developed countries such as the USA. The genomic profile alterations and dysregulated biological mechanisms commonly occur in PC. Macroautophagy/autophagy is a cell death process that is maintained at a basal level in physiological conditions, whereas its level often changes during tumorigenesis. The function of autophagy in human cancers is dual and can be oncogenic and onco-suppressor. Autophagy is a potent controller of tumorigenesis in PC. The supportive autophagy in PC escalates the growth rate of PC cells and its suppression can mediate cell death. Autophagy also determines the metastasis of PC cells, and it can control the EMT in affecting migration. Moreover, starvation and hypoxia can stimulate glycolysis, and glycolysis induction can be mediated by autophagy in enhancing tumorigenesis in PC. Furthermore, protective autophagy stimulates drug resistance and gemcitabine resistance in PC cells, and its inhibition can enhance radiosensitivity. Autophagy can degrade MHC-I to mediate immune evasion and also regulates polarization of macrophages in the tumor microenvironment. Modulation of autophagy activity is provided by silibinin, ursolic acid, chrysin and huaier in the treatment of PC. Non-coding RNAs are also controllers of autophagy in PC and its inhibition can improve therapy response in patients. Moreover, mitophagy shows dysregulation in PC, which can enhance the proliferation of PC cells. Therefore, a bioinformatics analysis demonstrates the dysregulation of autophagy-related proteins and genes in PC as biomarkers.

Mechanisms of cancer cell death induction by triptolide

Drug resistance is a hot topic issue in cancer research and therapy. Although cancer therapy including radiotherapy and anti-cancer drugs can kill malignant cells within the tumor, cancer cells can develop a wide range of mechanisms to resist the toxic effects of anti-cancer agents. Cancer cells may provide some mechanisms to resist oxidative stress and escape from apoptosis and attack by the immune system. Furthermore, cancer cells may resist senescence, pyroptosis, ferroptosis, necroptosis, and autophagic cell death by modulating several critical genes. The development of these mechanisms leads to resistance to anti-cancer drugs and also radiotherapy. Resistance to therapy can increase mortality and reduce survival following cancer therapy. Thus, overcoming mechanisms of resistance to cell death in malignant cells can facilitate tumor elimination and increase the efficiency of anti-cancer therapy. Natural-derived molecules are intriguing agents that may be suggested to be used as an adjuvant in combination with other anticancer drugs or radiotherapy to sensitize cancer cells to therapy with at least side effects. This paper aims to review the potential of triptolide for inducing various types of cell death in cancer cells. We review the induction or resistance to different cell death mechanisms such as apoptosis, autophagic cell death, senescence, pyroptosis, ferroptosis, and necrosis following the administration of triptolide. We also review the safety and future perspectives for triptolide and its derivatives in experimental and human studies. The anticancer potential of triptolide and its derivatives may make them effective adjuvants for enhancing tumor suppression in combination with anticancer therapy.

LncRNA SLC9A3-AS1 knockdown increases the sensitivity of liver cancer cell to triptolide by regulating miR-449b-5p-mediated glycolysis

Triptolide (TP) is involved in the progression of liver cancer. However, the detailed molecular network regulated through TP is still unclear. Long non-coding RNA (LncRNA) SLC9A3 exerts roles in various pathological progresses. Nevertheless, whether SLC9A3 affects the sensitivity of liver cancer cells to TP have not been uncovered. The content of SLC9A3-AS1 and miR-449b-5p was estimated by utilizing quantitative real-time polymerase-chain reaction (qRT-PCR). Cell counting kit 8 (CCK-8) assay was introduced to assess cell viability. Additionally, cell viability as well as invasion was tested via transwell assay. The direct binding between miR-449b-5p and SLC9A3-AS1 or LDHA was confirmed through luciferase reporter gene assay. Moreover, glycolysis rate was tested by calculating the uptake of glucose in addition to the production of lactate in Huh7 cells. LncRNA SLC9A3-AS1 was up-regulated in liver cancer tissue samples and cells. Knockdown of SLC9A3-AS1 notably further inhibited viability, migration as well as invasion in Huh7 cells. MiR-449b-5p was the direct downstream miRNA of SLC9A3-AS1 and was down-regulated by SLC9A3-AS1 in Huh7 cells. In addition, miR-449b-5p was reduced in liver cancer tissues and cells. Overexpressed miR-449b-5p increased the sensitivity of Huh7 cells to TP remarkably. Moreover, miR-449b-5p negatively regulated LDHA expression in Huh7 cells. This work proved that SLC9A3-AS1 increased the sensitivity of liver cancer cells to TP by regulating glycolysis rate mediated via miR-449b-5p/LDHA axis. These findings implied that TP is likely to be a potent agent for treating patients diagnosed with liver cancer.

Natural biomolecules and derivatives as anticancer immunomodulatory agents

Despite advancements in chemotherapy, the issue of resistance and non-responsiveness to many chemotherapeutic drugs that are currently in clinical use still remains. Recently, cancer immunotherapy has gathered attention as a novel treatment against select cancers. Immunomodulation is also emerging as an effective strategy to improve efficacy. Natural phytochemicals, with known anticancer properties, been reported to mediate their effects by modulating both traditional cancer pathways and immunity. The mechanism of phytochemical mediated-immunomodulatory activity may be attributed to the remodeling of the tumor immunosuppressive microenvironment and the sensitization of the immune system. This allows for improved recognition and targeting of cancer cells by the immune system and synergy with chemotherapeutics. In this review, we will discuss several well-known plant-derived biomolecules and examine their potential as immunomodulators, and therefore, as novel immunotherapies for cancer treatment.

The therapeutic potential of natural products for treating pancreatic cancer

Pancreatic cancer is one of the most malignant tumors of the digestive tract, with the poor prognosis and low 5-year survival rate less than 10%. Although surgical resection and chemotherapy as gemcitabine (first-line treatment) has been applied to the pancreatic cancer patients, the overall survival rates of pancreatic cancer are quite low due to drug resistance. Therefore, it is of urgent need to develop alternative strategies for its treatment. In this review, we summarized the major herbal drugs and metabolites, including curcumin, triptolide, Panax Notoginseng Saponins and their metabolites etc. These compounds with antioxidant, anti-angiogenic and anti-metastatic activities can inhibit the progression and metastasis of pancreatic cancer. Expecting to provide comprehensive information of potential natural products, our review provides valuable information and strategies for pancreatic cancer treatment.

Modulation and function of Pumilio proteins in cancer

Post-transcriptional regulation is involved in tumorigenesis, and in this control, RNA-binding proteins are the main protagonists. Pumilio proteins are highly conserved RNA-binding proteins that regulate many aspects of RNA processing. The dysregulation of Pumilio expression is associated with different types of cancer. This review summarizes the roles of Pumilio 1 and Pumilio 2 in cancer and discusses the factors that account for their distinct biological functions. Pumilio levels seem to be related to tumor progression and poor prognoses in some kinds of tumors, such as lung, pancreatic, prostate, and cervical cancers. Pumilio 1 is associated with cancer proliferation, migration, and invasion, and so is Pumilio 2, although there are contradictory reports regarding the latter. Furthermore, the circular RNA, circPUM1, has been described as a miRNAs sponge, regulating miRNA involved in the cell cycle. The expression and function of Pumilio proteins depend on the fine adjustment of a set of modulators, including miRNAs, lncRNAs, and circRNAs; this demonstrates that Pumilio plays an important role in tumorigenesis through a variety of regulatory axes.

Focusing on the Role of Natural Products in Overcoming Cancer Drug Resistance: An Autophagy-Based Perspective

Autophagy is a critical cellular adaptive response in tumor formation. Nutritional deficiency and hypoxia exacerbate autophagic flux in established malignancies, promoting tumor cell proliferation, migration, metastasis, and resistance to therapeutic interventions. Pro-survival autophagy inhibition may be a promising treatment option for advanced cancer. Furthermore, excessive or persistent autophagy is cytotoxic, resulting in tumor cell death. Targeted autophagy activation has also shown significant promise in the fight against tumor drug resistance. Several research groups have examined the ability of natural products (NPs) such as alkaloids, terpenoids, polyphenols, and anthraquinones to serve as autophagy inhibitors or activators. The data support the capacity of NPs that promote lethal autophagy or inhibit pro-survival autophagy from being employed against tumor drug resistance. This paper discusses the potential applications of NPs that regulate autophagy in the fight against tumor drug resistance, some limitations of the current studies, and future research needs and priorities.

Discovery of a novel water-soluble, rapid-release triptolide prodrug with improved drug-like properties and high efficacy in human acute myeloid leukemia

In this work, a series of water-soluble triptolide prodrugs were synthesized, and their triptolide release rate, pharmacokinetic characteristics and anti-tumor effect were measured. We found that inserting glycolic acid as a linker between triptolide and the cyclic amino acid accelerated the release of triptolide from prodrugs into the plasma while preserving its safety. Among them, prodrug TP-P1 was significantly better than Minnelide (the only water-soluble triptolide prodrug in clinical trials) in terms of release rate in plasma and synthetic yield. In mouse models of human acute myeloid leukemia (AML), TP-P1 was effective in reducing xenograft tumors at dose levels as low as 25 μg/kg, and eliminating tumors at dose 100 μg/kg. Furthermore, TP-P1 could significantly enhance the efficacy of FLT3 inhibitors in the treatment of AML. These experimental results showed the potential of TP-P1 as water-soluble prodrugs of triptolide.

Triptolide promotes autophagy to inhibit mesangial cell proliferation in IgA nephropathy via the CARD9/p38 MAPK pathway

Background

Mesangial cell proliferation is the most basic pathological feature of immunoglobulin A nephropathy (IgAN); however, the specific underlying mechanism and an appropriate therapeutic strategy are yet to be unearthed. This study aimed to investigate the therapeutic effect of triptolide (TP) on IgAN and the mechanism by which TP regulates autophagy and proliferation of mesangial cells through the CARD9/p38 MAPK pathway.

Methods

We established a TP‐treated IgAN mouse model and produced IgA1‐induced human mesangial cells (HMC) and divided them into control, TP, IgAN, and IgAN+TP groups. The levels of mesangial cell proliferation (PCNA, cyclin D1, cell viability, and cell cycle) and autophagy (P62, LC3 II, and autophagy flux rate) were measured, with the autophagy inhibitor 3‐Methyladenine used to explore the relationship between autophagy and proliferation. We observed CARD9 expression in renal biopsies from patients and analyzed its clinical significance. CARD9 siRNA and overexpression plasmids were constructed to investigate the changes in mesangial cell proliferation and autophagy as well as the expression of CARD9 and p‐p38 MAPK/p38 MAPK following TP treatment.

Results

Administering TP was safe and effectively alleviated mesangial cell proliferation in IgAN mice. Moreover, TP inhibited IgA1‐induced HMC proliferation by promoting autophagy. The high expression of CARD9 in IgAN patients was positively correlated with the severity of HMC proliferation. CARD9/p38 MAPK was involved in the regulation of HMC autophagy and proliferation, and TP promoted autophagy to inhibit HMC proliferation by downregulating the CARD9/p38 MAPK pathway in IgAN.

Conclusion

TP promotes autophagy to inhibit mesangial cell proliferation in IgAN via the CARD9/p38 MAPK pathway.

Triptolide Suppresses NF-κB-Mediated Inflammatory Responses and Activates Expression of Nrf2-Mediated Antioxidant Genes to Alleviate Caerulein-Induced Acute Pancreatitis

Triptolide (TP), the main active ingredient of Tripterygium wilfordii Hook.f., displays potent anti-inflammatory, antioxidant, and antiproliferative activities. In the present study, the effect of TP on acute pancreatitis and the underlying mechanisms of the disease were investigated using a caerulein-induced animal model of acute pancreatitis (AP) and an in vitro cell model. In vivo, pretreatment with TP notably ameliorated pancreatic damage, shown as the improvement in serum amylase and lipase levels and pancreatic morphology. Meanwhile, TP modulated the infiltration of neutrophils and macrophages (Ly6G staining and CD68 staining) and decreased the levels of proinflammatory factors (TNF-α and IL-6) through inhibiting the transactivation of nuclear factor-κB (NF-κB) in caerulein-treated mice. Furthermore, TP reverted changes in oxidative stress markers, including pancreatic glutathione (GSH), superoxide dismutase (SOD), and malondialdehyde (MDA), in acute pancreatitis mice. Additionally, TP pretreatment inhibited intracellular reactive oxygen species (ROS) levels via upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) expression and Nrf2-regulated redox genes expression (HO-1, SOD1, GPx1 and NQO1) in vitro. Taken together, our data suggest that TP exert protection against pancreatic inflammation and tissue damage by inhibiting NF-κB transactivation, modulating immune cell responses and activating the Nrf2-mediated antioxidative system, thereby alleviating acute pancreatitis.

Terpenoids' anti-cancer effects: focus on autophagy

Terpenoids are the largest class of natural products, most of which are derived from plants. Amongst their numerous biological properties, their anti-tumor effects are of interest for they are extremely diverse which include anti-proliferative, apoptotic, anti-angiogenic, and anti-metastatic activities. Recently, several in vitro and in vivo studies have been dedicated to understanding the 'terpenoid induced autophagy' phenomenon in cancer cells. Light has already been shed on the intricacy of apoptosis and autophagy relationship. This latter crosstalk is driven by the delicate balance between activating or silencing of certain proteins whereby the outcome is expressed via interrelated signaling pathways. In this review, we focus on nine of the most studied terpenoids and on their cell death and autophagic activity. These terpenoids are grouped in three classes: sesquiterpenoid (artemisinin, parthenolide), diterpenoids (oridonin, triptolide), and triterpenoids (alisol, betulinic acid, oleanolic acid, platycodin D, and ursolic acid). We have selected these nine terpenoids among others as they belong to the different major classes of terpenoids and our extensive search of the literature indicated that they were the most studied in terms of autophagy in cancer. These terpenoids alone demonstrate the complexity by which these secondary metabolites induce autophagy via complex signaling pathways such as MAPK/ERK/JNK, PI3K/AKT/mTOR, AMPK, NF-kB, and reactive oxygen species. Moreover, induction of autophagy can be either destructive or protective in tumor cells. Nevertheless, should this phenomenon be well understood, we ought to be able to exploit it to create novel therapies and design more effective regimens in the management and treatment of cancer.

Triptolide: pharmacological spectrum, biosynthesis, chemical synthesis and derivatives

Triptolide, an abietane-type diterpenoid isolated from Tripterygium wilfordii Hook. F., has significant pharmacological activity. Research results show that triptolide has obvious inhibitory effects on many solid tumors. Therefore, triptolide has become one of the lead compounds candidates for being the next "blockbuster" drug, and multiple triptolide derivatives have entered clinical research. An increasing number of researchers have developed triptolide synthesis methods to meet the clinical need. To provide new ideas for researchers in different disciplines and connect different disciplines with researchers aiming to solve scientific problems more efficiently, this article reviews the research progress made with analyzes of triptolide pharmacological activity, biosynthetic pathways, and chemical synthesis pathways and reported in toxicological and clinical studies of derivatives over the past 20 years, which have laid the foundation for subsequent researchers to study triptolide in many ways.

Pancreatic Cancer (PDAC): Introduction of Evidence-Based Complementary Measures into Integrative Clinical Management

The most common form of pancreatic cancer is pancreatic ductal adenocarcinoma (PDAC), which comprises some 85% of all cases. Currently, this is the fourth highest cause of cancer mortality worldwide and its incidence is rising steeply. Commonly applied clinical therapies offer limited chance of a lasting cure and the five-year survival rate is one of the lowest of the commonly occurring cancers. This review cultivates the hypothesis that the best management of PDAC would be possible by integrating 'western' clinical medicine with evidence-based complementary measures. Protecting the liver, where PDAC frequently first spreads, is also given some consideration. Overall, the complementary measures are divided into three groups: dietary factors, nutraceutical agents and lifestyle. In turn, dietary factors are considered as general conditioners, multi-factorial foodstuffs and specific compounds. The general conditioners are alkalinity, low-glycemic index and low-cholesterol. The multi-factorial foodstuffs comprise red meat, fish, fruit/vegetables, dairy, honey and coffee. The available evidence for the beneficial effects of the specific dietary and nutraceutical agents was considered at four levels (in order of prominence): clinical trials, meta-analyses, in vivo tests and in vitro studies. Thus, 9 specific agents were identified (6 dietary and 3 nutraceutical) as acceptable for integration with gemcitabine chemotherapy, the first-line treatment for pancreatic cancer. The specific dietary agents were the following: Vitamins A, C, D and E, genistein and curcumin. As nutraceutical compounds, propolis, triptolide and cannabidiol were accepted. The 9 complementary agents were sub-grouped into two with reference to the main 'hallmarks of cancer'. Lifestyle factors covered obesity, diabetes, smoking, alcohol and exercise. An integrative treatment regimen was devised for the management of PDAC patients. This involved combining first-line gemcitabine chemotherapy with the two sub-groups of complementary agents alternately in weekly cycles. The review concludes that integrated management currently offers the best patient outcome. Opportunities to be investigated in the future include emerging modalities, precision medicine, the nerve input to tumors and, importantly, clinical trials.

Traditional Chinese medicine may be further explored as candidate drugs for pancreatic cancer: A review

Pancreatic cancer is a disease with a high mortality rate. Although survival rates for different types of cancers have improved in recent years, the five-year survival rate of pancreatic cancer stands at 8%. Moreover, the current first-line therapy, gemcitabine, results in low remission rates and is associated with drug resistance problems. Alternative treatments for pancreatic cancer such as surgery, chemotherapy and radiation therapy provide marginal remission and survival rates. This calls for the search of more effective drugs or treatments. Traditional Chinese medicine contains numerous bioactive ingredients some of which show activity against pancreatic cancer. In this review, we summarize the mechanisms of five types of traditional Chinese medicine monomers. In so-doing, we provide new potential drug candidates for the treatment of pancreatic cancer.

Triptolide inhibits pancreatic cancer cell proliferation and migration via down-regulating PLAU based on network pharmacology of Tripterygium wilfordii Hook F

Tripterygium wilfordii Hook F (TwHF) exhibits anti-tumor efficacy in pancreatic ductal adenocarcinoma (PDAC), however the pharmacological mechanisms are unclear due to complicated formulae and target genes. Using Traditional Chinese Medicine Systems Pharmacology and GeneCards databases, we performed a network pharmacology (NP) of TwHF and screened out 22 ingredients and 25 target genes associated with PDAC. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the 25 target genes were performed. Using STRING database, protein-protein interaction network of the 25 target genes was constructed, and indicated that triptolide (TL)-plasminogen activator urokinase (PLAU) as a potential target for PDAC treatment. Hence, in vitro experiments were performed and validated that TL inhibited PDAC cell proliferation and migration by suppressing PLAU expression. The results of Western blot suggested that PLAU activated endothelial-mesenchymal transition (EMT) progression. In two Gene Expression Omnibus datasets (GSE16515 and GSE28735), PLAU was up-regulated in tumor tissues, and PLAU overexpression was associated with poor overall survival of PDAC cohort of The Cancer Genome Atlas (P < 0.01). Immunohistochemistry illustrated that overexpression of PLAU protein was related to lymph node metastasis in 20 PDAC patients (P < 0.01). Based on NP of TwHF, we identified and validated that TL-PLAU could serve as a potential target for PDAC treatment.

Inhibition of cyclinB1 Suppressed the Proliferation, Invasion, and Epithelial Mesenchymal Transition of Hepatocellular Carcinoma Cells and Enhanced the Sensitivity to TRAIL-Induced Apoptosis

Background

CyclinB1 is highly expressed in various tumor tissues and plays an important role in tumor progression. However, its role in hepatocellular carcinoma (HCC) remains unclear. Therefore, the aim of this study was to explore the role of cyclinB1 in the development and progression of HCC.

Methods

The expression of cyclinB1 was analyzed using the Gene Expression Profiling Interactive Analysis (GEPIA) database, and detected in HCC tissues and HCC cell lines through quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting. CyclinB1-short hairpin RNA (Sh-cyclinB1) was transfected into HCC cells to knockdown cyclinB1, and the effect of cyclinB1 knockdown on HCC was examined via the MTT assay, colony formation assay, wound healing assay, scratch assay, cell cycle analysis in vitro, and xenograft model in nude mice. In addition, the role of cyclinB1 on tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis was measured using flow cytometry and Western blotting.

Results

The GEPIA database analysis showed that cyclinB1 was highly expressed in HCC tissues. The results of qRT-PCR and Western blotting proved that the expression of cyclinB1 was significantly increased in HCC tissues and cell lines. The data of the MTT assay, colony formation assay, and cell cycle analysis indicated that cyclinB1 knockdown inhibited the proliferation of HCC cells. In addition, cell migration, invasion, and epithelial mesenchymal transition were also impaired by cyclinB1 knockdown. Furthermore, the xenograft model in nude mice demonstrated that inhibition of cyclinB1 suppressed tumor growth and metastasis in vivo. Finally, the results of flow cytometry and Western blotting indicated that inhibition of cyclinB1 enhanced the sensitivity of HCC cells to TRAIL-induced apoptosis.

Conclusion

Overall, these data provide reasonable evidence that cyclinB1 may serve as a proto-oncogene during the progression of HCC.

PUM1 knockdown prevents tumor progression by activating the PERK/eIF2/ATF4 signaling pathway in pancreatic adenocarcinoma cells

Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with very poor prognosis. Therefore, it is important to fully understand the molecular mechanism underlying its occurrence and development. Pumilio RNA-binding family member 1 (PUM1) has been reported to function as an oncogene in ovarian cancer and nonsmall cell lung cancer. However, its role and mechanism in PDAC have not been fully illuminated. Here, we found that the PUM1 protein levels were higher in PDAC tissues than in adjacent tissues and that PUM1 levels were significantly associated with TNM stage and overall survival time, indicating a correlation between high PUM1 expression and poor prognosis in patients with PDAC. In vitro and in vivo assays showed that PUM1 knockdown inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT), and promoted apoptosis in MIA PaCa-2 and PANC-1 cells. Through cDNA microarrays and ingenuity pathway analysis, we found that the activation of the eIF2 signaling pathway significantly correlated with PUM1 knockdown. These results were further confirmed by the increased levels of key components of the eIF2 signaling pathway, p-PERK, p-EIF2A, and ATF4 in PUM1 knockdown cells. We also found that PUM1 levels have a significant negative correlation with p-PERK levels in PDAC tissues and that PERK overexpression inhibited cell proliferation, migration, invasion, and EMT, and promoted apoptosis in vitro. Moreover, a PERK inhibitor alleviated the effects of PUM1 knockdown on cell proliferation, apoptosis, migration, invasion, and EMT. Taken together, our results revealed that PUM1 knockdown suppressed cell growth, invasion, and metastasis, and promoted apoptosis by activating the PERK/eIF2/ATF4 signaling pathway in PDAC cells. PUM1 could be a potential target to develop pharmaceuticals and novel therapeutic strategies for the treatment of PDAC.