Efficacy and safety of gemcitabine-capecitabine combination therapy for pancreatic cancer: A systematic review and meta-analysis of randomized controlled trials

LncRNAs associated with vascular mimicry establish a novel molecular subtype and prognostic model for pancreatic cancer

BACKGROUND

Vascular mimicry (VM) epitomizes an innovative tumor angiogenesis pathway, potentially serving as an alternate conduit under the assumption of traditional tumor angiogenesis pathway inhibition. The role of VM in pancreatic cancer (PC), however, remains unexplored.

METHODS

Using differential analysis and Spearman correlation, we identified key long non-coding RNAs (lncRNAs) signatures in PC from the collected set of VM-associated genes in the literature. We identified optimal clusters using the non-negative matrix decomposition (NMF) algorithm, and then compared clinicopathological features and prognostic differences between clusters. We also assessed tumor microenvironmental (TME) differences between clusters using multiple algorithms. Using univariate Cox regression analyses as well as lasso regression, we constructed and validated new lncRNA prognostic risk models for PC. We used Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) to analyze model-enriched functions and pathways. Nomograms were then developed to predict patient survival in association with clinicopathological factors. In addition, single-cell RNA-sequencing (scRNA-seq) analysis was used to analyze the expression patterns of VM-related genes and lncRNAs in the PC of TME. Finally, we used the Connectivity Map (cMap) database to predict local anaesthetics that could modify the VM of PC.

RESULTS

In this study, we developed a novel three-cluster molecular subtype using the identified VM-associated lncRNA signatures of PC. The different subtypes have significantly different clinical characteristics and prognostic value, and also show differential treatment response and TME. Following an in-depth analysis, we constructed and validated a novel prognostic risk model for PC based on the VM-associated lncRNA signatures. Enrichment analysis suggested that high riskscores were significantly associated with functions and pathways, including extracellular matrix remodeling, et al. In addition, we predicted eight local anaesthetics that could modulate VM in PC. Finally, we discovered differential expression of VM-related genes and lncRNAs across various cell types within pancreatic cancer.

CONCLUSION

VM has a critical role in PC. This study pioneers the development of a VM-based molecular subtype that demonstrates substantial differentiation in PC populations. Furthermore, we highlighted the significance of VM within the immune microenvironment of PC. Moreover, VM might contribute to PC tumorigenesis through its mediation of mesenchymal remodeling and endothelial transdifferentiation-related pathways, which offers a new perspective on its role in PC.

Evolving utility of exosomes in pancreatic cancer management

Despite the development of newer oncological treatment, the survival of patients with pancreatic cancer (PC) remains poor. Recent studies have identified exosomes as essential mediators of intercellular communications and play a vital role in tumor initiation, metastasis and chemoresistance. Thus, the utility of liquid biopsies using exosomes in PC management can be used for early detection, diagnosis, monitoring as well as drug delivery vehicles for cancer therapy. This review summarizes the function, and clinical applications of exosomes in cancers as minimally invasive liquid biomarker in diagnostic, prognostic and therapeutic roles.

The efficacy and safety of gemcitabine-based combination therapy vs. gemcitabine alone for the treatment of advanced pancreatic cancer: a systematic review and meta-analysis

Background

Gemcitabine (GEM) is used as a standard first-line drug to effectively alleviate symptoms and prolong survival time for advanced pancreatic cancer. Most randomized controlled trials (RCTs) show that GEM-based combination therapy is better than GEM alone, while some RCTs have the opposite conclusion. This study aimed to investigate whether GEM-based combination therapy would be superior to GEM alone by a systematic review and meta-analysis.

Methods

According to the PICOS principles, RCTs (S) focused on comparing GEM-based combination therapy (I) vs. GEM alone (C) for advanced pancreatic cancer (P) were collected from eight electronic databases, outcome variables mainly include survival status and adverse events (AEs) (O). Review Manager 5.4 was used to evaluate the pooled effects of the results among selected articles. Pooled estimate of hazard ratio (HR) and odds ratio (OR) with 95% confidence interval (CI) were used as measures of effect sizes. Quality assessment for individual study was performed using the Cochrane tool for risk of bias.

Results

A total of 17 studies including 5,197 patients were selected in this analysis. The pooled results revealed that GEM-based combination therapy significantly improved the overall survival (OS; HR =0.84; 95% CI: 0.79 to 0.90; P<0.00001), progression-free survival (PFS; HR =0.78; 95% CI: 0.72 to 0.84; P<0.00001), overall response rate (ORR; OR =1.92; 95% CI: 1.61 to 2.30; P<0.00001), 1-year survival rate (OR =1.44; 95% CI: 1.02 to 2.03; P=0.04), respectively. Subgroup analysis showed that the efficacy of GEM plus capecitabine (CAP) and GEM plus S-1 was better than that of GEM alone, while GEM plus cisplatin (CIS) did not achieve an improved effect. GEM-based combination therapy can significantly increase the incidence of AEs, such as leukopenia (P<0.001), neutropenia (P<0.001), anemia (P<0.05), nausea (P<0.001), diarrhea (P<0.05), and stomatitis (P<0.001). No publication bias existed in our meta-analysis (P>0.10).

Discussion

Our study supported that GEM-based combination therapy was more beneficial to improve patient's survival than GEM alone, while there was no additional benefits in GEM plus CIS. We also found that GEM-based combination therapy increased the incidence of AEs. Clinicians need to choose the appropriate combination therapy according to the specific situation.