Longitudinal studies can identify distinct inflammatory cytokines associated with the inhibition or progression of liver cancer

Background and Aims Chronic diseases such as nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) are associated with chronic inflammation. However, controversial reports as to the key cytokines involved in the process of chronic inflammation hinder development of targeted therapies for patients. This is because, chronic inflammatory process cannot be fully understood by studying the mechanisms of the disease in a short-term or isolated fashion. Understanding of the trend of inflammatory cytokines through longitudinal studies could provide a profound insight into the process of disease progression. Methods We performed a longitudinal analysis of inflammatory cytokines/chemokines and faecal microbiome dysbiosis associated with the diet-induced progression of NAFLD to HCC in diet-induced animal model of NAFLD comparing males and females, since males show a higher incidence of these diseases than females do. Results Longitudinal analyses revealed that a transient and timely increase in LIF and TMIP1 was associated with the inhibition of the progression of NAFLD to HCC in females. On the other hand, chronically increasing trends in CCL12, CCL17, CXCL9 and LIX/CXCL5 were associated with the promotion of the progression of NAFLD to HCC in males. Conclusions We provided empirical evidence that a methodological shift from snapshot observations to longitudinal data collection and analysis can provide a better understanding of chronic liver diseases.