Synergistic effects of SARS-CoV-2 and bacterial co-infections on gut microbiota dysbiosis, tumor progression, and therapeutic response in gastrointestinal cancers

Background: The COVID-19 pandemic has significantly impacted patients with gastrointestinal (GI) cancers, particularly those undergoing active treatment. This review explores the complex interplay between SARS-CoV-2 infection and bacterial co-infections in the context of GI malignancies. We examine how SARS-CoV-2-induced gut microbiota dysbiosis can exacerbate tumor progression, influence immune responses, and affect therapeutic outcomes. Additionally, we discuss the clinical implications of these interactions, including morbidity, mortality, and treatment challenges. Future perspectives highlight the importance of microbiome profiling, immune monitoring, and personalized therapeutic approaches.