Pancreatic cancer is an extremely dismal malignance. Chemotherapy has been widely applied to treat this intractable tumor. It has exclusive tumor microenvironment (TME), characterized by dense desmoplasia and profound infiltrations of immunosuppressive cells. Interactions between stromal cells and cancer cells play vital roles to affect the biological behaviors of pancreatic cancer. Targeting the stromal components of pancreatic cancer has shown promising results. In addition to the direct toxic effects of chemotherapeutic drugs on cancer cells, they can also remodel the TME, eventually affecting their efficacy. Herein, we reviewed the following four aspects; (1) clinical landmark advances of chemotherapy in pancreatic cancer, since 2000; (2) interactions and mechanisms between stromal cells and pancreatic cancer cells; (3) remodeling effects and mechanisms of chemotherapy on TME; (4) targeting stromal components in pancreatic cancer.

Ferroptosis, a novel form of cell death triggered by iron-dependent phospholipid peroxidation, presents significant therapeutic potential across diverse cancer types. Central to cellular metabolism, the metabolic pathways associated with ferroptosis are discernible in both cancerous and immune cells. This review begins by delving into the intricate reciprocal regulation of ferroptosis between cancer and immune cells. It subsequently details how factors within the tumor microenvironment (TME) such as nutrient scarcity, hypoxia, and cellular density modulate ferroptosis sensitivity. We conclude by offering a comprehensive examination of distinct immunophenotypes and environmental and metabolic targets geared towards enhancing ferroptosis responsiveness within the TME. In sum, tailoring precise ferroptosis interventions and combination strategies to suit the unique TME of specific cancers may herald improved patient outcomes.

Objective: To present comprehensive information on the clinicopathological, molecular, survival characteristics, and quality of life (QOL) after surgery for solid pseudopapillary neoplasm (SPN) of the pancreas in a large cohort after long-term follow-up. Background: SPN is a rare tumor with an uncertain malignant potential, and solid information on long-term prognosis and QOL remains limited. Methods: All hospitalized patients with SPNs who underwent surgery between 2001 and 2021 at the Peking Union Medical College Hospital were retrospectively reviewed. The clinicopathological characteristics of the patients were retrieved. A cross-sectional telephone questionnaire was administered to inquire about the QOL. Molecular analyses were performed using whole-exome sequencing. Results: Exactly 454 patients with SPN were enrolled, of whom 18.5% were males and 81.5% were females. The mean patient age was 31 ± 12 years. In total, 61.3% of the patients had no symptoms. The size of the tumors was 5.38 ± 3.70 cm; 83.4% were solid cystic tumors, and 40.1% had calcifications. The proportions of local resection, distal pancreatectomy with or without splenectomy, and pancreaticoduodenectomy with or without pylorus preservation were 29.7%, 28.9% or 22.9%, and 11% or 6.8%, respectively. Over the years, there has been a significant shift from open to minimally invasive surgery. Among all surgical procedures, pylorus-preserving pancreaticoduodenectomy (PPPD) had the highest incidence of grade 2 to 4 complications (up to 32.3%), compared with 6.7% in distal pancreatectomy (P < 0.001). Regarding histopathology, tissue invasion, perineural invasion, cancerous microvascular emboli, lymph node metastasis, and distant metastasis were present in 16.5%, 2.2%, 0.7%, 2.0%, and 3.1% of patients, respectively. Sixty patients were lost to follow-up. Sixteen of the 390 patients who underwent resection (4.1%) experienced local recurrence or distant metastasis after surgery. In total, 361 patients responded to the telephone survey. Nearly 80% of patients claimed their QOL was not significantly affected after surgery; however, the remaining 20% complained of lower QOL during 3 to 6 years of follow-up after surgery. No clinicopathological factor could reliably predict clinical recurrence or metastasis after resection. A total of 28 driver genes were detected with mutations in at least 2 tumor samples and the top 3 frequently mutated genes were CTNNB1, ATRNL1, and MUC16. Conclusions: This study presented the largest cohort of patients with SPN after surgery from a single center and reported the QOL of these patients. SPN is associated with extremely favorable long-term survival, even in patients with metastasis, and most patients have a good QOL after surgery.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant tumors. Macrophages are abundant in the tumor microenvironment, making them an attractive target for therapeutic intervention. While current immunotherapies, including immune checkpoint inhibition (ICI) and chimeric antigen receptor T (CAR-T) cells, have shown limited efficacy in pancreatic cancer, a novel approach involving chimeric antigen receptor macrophages (CAR-M) has, although promising, not been explored in pancreatic cancer. In this study, we first investigated the role of CAR-M cells targeting c-MET in pancreatic cancer. The effectiveness and rationality of c-MET as a target for CAR-M in pancreatic cancer were validated through bioinformatic analyses and immunohistochemical staining of samples from pancreatic cancer patients. We utilized flow cytometry and bioluminescence detection methods to demonstrate the specific binding and phagocytic killing effect of CAR-M on pancreatic cancer cells. Additionally, we observed the process of CAR-M engulfing pancreatic cancer cells using confocal microscopy and a long-term fluorescence live cell imaging system. In an in situ tumor model transplanted into NOD/SCID mice, we administered intraperitoneal injections of CAR-M to confirm its inhibitory function on pancreatic cancer. Furthermore, we validated these findings in human monocyte-derived macrophages (hMDM). Bioinformatics and tumor tissue microarray analyses revealed significantly higher expression levels of c-MET in tumor tissues, compared to the paired peritumoral tissues, and higher c-MET expression correlated with worse patient survival. CAR-M cells were engineered using human monocytic THP-1 cell line and hMDM targeting c-MET (CAR-M-c-MET). The CAR-M-c-MET cells demonstrated highly specific binding to pancreatic cancer cells and exhibited more phagocytosis and killing abilities than the pro-inflammatory polarized control macrophages. In addition, CAR-M-c-MET cells synergized with various cytotoxic chemotherapeutic drugs. In a NOD/SCID murine model, intraperitoneally injected CAR-M-c-MET cells rapidly migrated to tumor tissue and substantially inhibited tumor growth, which did not lead to obvious side effects. Cytokine arrays and mRNA sequencing showed that CAR-M-c-MET produced higher levels of immune activators than control macrophages. This study provides compelling evidence for the safety and efficacy of CAR-M therapy in treating pancreatic cancer. The results demonstrate that CAR-M-c-MET significantly suppresses pancreatic cancer progression and enhances the effectiveness of cytotoxic chemotherapy. Remarkably, no discernible side effects occur. Further clinical trials are warranted in human pancreatic cancer patients.