In 2019, the World Journal of Gastroenterology (WJG) has published the 4^th issue which containing 10 articles including 3 reviews, and 7 original articles, contributed by scientists worldwide. Among these comprehensive articles are (1) “Human immunodeficiency virus and hepatotropic viruses co-morbidities as the inducers of liver injury progression”, a Review by Murali Ganesan, PhD, Instructor, et al from Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, United States; (2) “Interplay between post-translational cyclooxygenase-2 modifications and the metabolic and proteomic profile in a colorectal cancer cohort”, a Basic Study by Lisardo Boscá, PhD, Professor, et al from Department of Metabolism and Physiopathology of Inflammatory Diseases, Instituto de investigaciones Biomédicas “Alberto Sols”, Spain; and (3) “Treatment for gastric ‘indefinite for neoplasm/dysplasia’ lesions based on predictive factors”, a Retrospective Study by Ho Suk Kang, MD, Assistant Professor, et al from Division of Gastroenterology, Department of Internal Medicine, Hallym University Sacred Heart Hospital, South Korea, etc. We invite you to peruse all 10 articles in this issue, as they present the latest research progress/findings and provide insightful comments in gastroenterology and hepatology that will guide basic research and clinical practice in these fields.

This journal is an open-access journal which allows free immediate access to all full-text articles. For details, please visit: Volume 25, Issue 4, January 28, 2019.

Figure 1 The cover of the issue. Editorial board member of World Journal of Gastroenterology, Lisardo Boscá, BM BCh, PhD, Doctor, Professor, Senior Research Fellow, Department of Metabolism and Physiopathology of Inflammatory Diseases, Insituto de Investigaciones Biomédicas ALberto Sols (CSIC-UAM), Madrid 28029, Spain.

We encourage gastroenterologists and hepatologists worldwide to submit manuscripts to the WJG describing their original basic or clinical research findings that are of high academic value and which report new diagnostic techniques or summarize their treatment experiences.