A Mendelian analysis of the causality between inflammatory cytokines and digestive tract cancers

In this study, we performed a two-sample Mendelian randomization (MR) analysis to assess the causality between inflammatory cytokines and the risk of digestive tract cancers (DTCs). Furthermore, we conducted a molecular docking study to predict the therapeutic mechanisms of traditional Chinese medicine (TCM) compounds in the treatment of DTCs.

In our MR analysis, genetic variations associated with eight types of DTCs were utilized, which were sourced from a large publicly available genome-wide association study dataset (7929 cases and 1 742 407 controls of European ancestry) and inflammatory cytokines data from a genome-wide association study summary of 8293 European participants. Inverse-variance weighted method, MR-Egger, and weighted median were performed to analyze and strengthen the final results. We investigated the effects of 41 inflammatory molecules on 8 types of DTCs. Subsequently, the effect of DTCs on positive inflammatory factors was analyzed by means of inverse MR. Molecular docking was exploited to predict therapeutic targets with TCM compounds.

Interleukin-7, interleukin-16, macrophage colony-stimulating factor, monokine induced by interferon-gamma, and vascular endothelial growth factor may be significantly associated with various types of DTCs. Five TCM compounds (baicalin, berberine, curcumin, emodin, and salidroside) demonstrated better binding energies to both interleukin-7 and vascular endothelial growth factor than carboplatin.

This study provides strong evidence to support the potential causality of some inflammatory cytokines on DTCs and indicates the potential molecular mechanism of TCM compounds in the treatment of DTCs. Key message What is already known on this topic  The increasing evidence indicates that inflammatory cytokines are implicated in the pathogenesis of digestive tract cancers (DTCs). Nevertheless, the causal relationship between inflammatory cytokines and DTCs remains indistinct. Additionally, certain traditional Chinese medicine compounds have been demonstrated to treat DTCs by influencing inflammatory factors, yet their underlying potential mechanisms remain ambiguous. What this study adds  In this study, Mendelian randomization analysis was performed for the first time regarding the causality between human inflammatory cytokines and eight types of DTCs, which revealed that inflammatory factors may play different roles in different types of DTCs. Moreover, molecular docking of key inflammatory factors was implemented, indicating the targets for drug actions. How this study might affect research, practice, or policy  This research has the potential to reveal the causality between 41 inflammatory factors and 8 DTCs, offering novel perspectives for the prevention and management strategies of DTCs. Additionally, it indicates the targets for the actions of traditional Chinese medicine on the key inflammatory factors of these cancers.