Apoptosis resistance is to a large extent a major obstacle leading to chemotherapy failure during cancer treatment. Bypassing the apoptotic pathway to induce cancer cell death is considered to be a promising approach to overcoming this problem. Necroptosis is a regulated necrotic cell death modality in a caspase-independent fashion and is mainly mediated by Receptor-Interacting Protein 1 (RIP1), RIP3, and Mixed Lineage Kinase Domain-Like (MLKL). Necroptosis serves as an alternative mode of programmed cell death overcoming apoptosis resistance and may trigger and amplify antitumor immunity in cancer therapy. The role of necroptosis in cancer is complicated. The expression of key regulators of the necroptotic pathway is generally downregulated in cancer cells, suggesting that cancer cells may also evade necroptosis to survive; however, in certain types of cancer, the expression level of key mediators is elevated. Necroptosis can elicit strong adaptive immune responses that may defend against tumor progression; however, the recruited inflammatory response may also promote tumorigenesis and cancer metastasis, and necroptosis may generate an immunosuppressive tumor microenvironment. Necroptosis also reportedly promotes oncogenesis and cancer metastasis despite evidence demonstrating its antimetastatic role in cancer. In addition, necroptotic microenvironments can direct lineage commitment to determine cancer subtype development in liver cancer. A plethora of compounds and drugs targeting necroptosis exhibit potential antitumor efficacy, but their clinical feasibility must be validated. Better knowledge of the necroptotic pathway mechanism and its physiological and pathological functions is urgently required to solve the remaining mysteries surrounding the role of necroptosis in cancer. In this review, we briefly introduce the molecular mechanism and characteristics of necroptosis, the interplay between necroptosis and other cell death mechanisms, crosstalk of necroptosis and metabolic signaling and detection methods. We also summarize the intricate role of necroptosis in tumor progression, cancer metastasis, prognosis of cancer patients, cancer immunity regulation, cancer subtype determination and cancer therapeutics.

To examine potential biomarkers in Lewis negative patients with pancreatic cancer. Carbohydrate antigen 19–9 (CA19–9) is currently the most important and widely used biomarker in pancreatic cancer. However, approximately 5 to 10% of the population are Lewis negative individuals, and they are documented to have scarce or no CA19–9 secretion. Therefore, it is necessary to explore potential biomarkers to compensate for this drawback. Lewis genotypes were determined in a large cohort of patients with pancreatic cancer (682 cases) and controls (525 cases) by sequencing the Fucosyltransferase 3 (FUT3) gene from genomic DNA. Potential biomarkers were examined in patients with Lewis negative genotypes and normal subjects. The impact of potential biomarkers on tumor burden and survival was analyzed. Forty-seven (6.9%) patients with pancreatic cancer had Lewis negative genotypes. Carcinoembryonic antigen (CEA) and CA125 had greater sensitivity than other biomarkers in Lewis negative patients with pancreatic cancer [CEA, 63.8%; CA125, 51.1%; CA72–4, 25.5%; CA15–3, 21.3%; CA19–9, 19.1%; CA50, 12.8%; CA242, 10.6%; and alpha-fetoprotein (AFP), 0.0%]. In addition, both CEA (98.0%) and CA125 (93.8%) showed a high specificity. Compared with other biomarkers, CEA (60.9%) was sensitive for stage I, II diseases and CA125 (75.0%) was sensitive for stage III, IV diseases. CEA and CA125 were associated with tumor metastasis and therapeutic response. CEA and CA125 have the potential to be applied as biomarkers in Lewis negative patients with pancreatic cancer. CEA and CA125 should be routinely measured for all patients with pancreatic cancer.

Cell‐free circulating tumor DNA (ctDNA) in plasma has been used as a potential noninvasive biomarker for various tumors. Our study was performed to evaluate the clinical implications of ctDNA detection in patients with metastatic pancreatic cancer. First, we attempted to prospectively screen a panel of 60 genes in cell‐free DNA (cfDNA) from ten metastatic pancreatic cancer patients via exome sequencing. Second, droplet digital PCR (ddPCR) was used to identify potential mutations in a cohort of 188 patients with metastatic pancreatic cancer. Finally, to preliminary evaluate the potential role of ctDNA in monitoring tumor responses following chemotherapy, we detected the presence of ctDNA in serial plasma samples from 13 metastatic pancreatic cancer patients (Clinical trial: NCT02017015). The analysis revealed five somatic mutations at BRCA2, EGFR, KDR and ERBB2 gene loci. The frequencies of ctDNA mutation at BRCA2, KDR, EGFR, ERBB2 exon17 and ERBB2 exon27 were 11.7%, 13.8%, 13.3%, 13.3% and 6.4% respectively. Univariate and multivariate analyses identified the ERBB2 exon17 mutation (p = 0.035, HR = 1.61) as an independent factor associated with overall survival among metastatic pancreatic cancer patients. Furthermore, the rate of coincident detection of ctDNA and response to treatment as assessed by CT imaging was 76.9% (10 of 13 cases), and the presence of ctDNA provided the earliest measure of treatment in 6 of 10 patients (60%). ctDNA sequencing may have clinical value for determining metastatic pancreatic cancer treatment and monitoring the tumor response.