Hepatitis D virus (HDV), a satellite virus requiring hepatitis B surface antigen (HBsAg) for propagation, is a hepatotropic virus implicated in acute and chronic viral hepatitis, with an accentuated risk of cirrhosis and hepatocellular carcinoma. The epidemiology of HDV infection is underestimated owing to underdiagnosis and low screening rates. Being inherently defective, HDV depends on HBsAg, the envelope protein of the hepatitis B virus (HBV), for hepatocyte entry and exit. However, viral replication is then HBV-independent but dependent on the host cell RNA polymerases. Infection can either be a coinfection with HBV or superinfection in individuals with pre-existing HBV, with the latter exhibiting a higher propensity for progression to chronicity. Clinical manifestations could range from acute hepatitis to acute flares in chronic hepatitis to rapidly progressive chronic liver disease. For decades, the treatment of HDV infection relied heavily on conventional and pegylated interferons (PEG-IFNs), which, despite limited efficacy and high relapse rates, continue to be a therapeutic option in patients with compensated liver disease. The past decade witnessed an advanced understanding of HDV virology and pathogenesis, which led to the development of multiple specific and targeted therapeutic agents, most notably the HDV viral entry inhibitor, bulevirtide, and the prenylation inhibitor, lonafarnib. In 2020, bulevirtide became the first drug approved in the European Union to treat chronic HDV with compensated liver disease. The emergence of lambda interferons, nucleic acid polymers, RNA silencers, and immune modulators further expands the therapeutic landscape. Combination regimens leveraging complementary mechanisms are promising but require further validation to optimize dosing and treatment durations. While novel therapies provide hope, significant unmet needs remain, especially for patients with decompensated cirrhosis. Future research must prioritize comprehensive strategies to enhance treatment efficacy and accessibility, offering a brighter prognosis for those affected by this devastating virus.

Pancreatic cystic lesions are frequently found incidentally on cross-sectional imaging and are broadly classified into mucinous and non-mucinous cysts. While some exhibit benign behavior, others have a malignant potential and are considered noninvasive precursors of pancreatic ductal adenocarcinoma. Guidelines from various societies propose risk stratification based on morphologic features and cyst fluid analysis. Fluid analysis through EUS-guided fine needle aspiration contributes to improved classification and recently, targeted DNA or RNA-based next generation sequencing is emerging as a critical investigation tool for diagnostic confirmation and risk stratification of pancreatic cysts. Each of these modalities has specific strengths and limitations, highlighting the need for a multi-modal approach for comprehensive assessment to guide clinical decision making. In this perspective, we aim to provide a thorough clinicopathologic framework for diagnosing and risk stratifying pancreatic cysts encompassing imaging findings, cyst fluid analyses, and next generation sequencing.

Diverticular disease of the colon is a very important digestive disease and its management depends on the characteristics of the disease and the patient and the resources available. There are benefits and harms of open and laparoscopic Hartmann’s procedure, laparoscopic peritoneal lavage, sigmoidectomy, and primary anastomosis. There are many gaps to be eliminated in the future, such as real risks, benefits, and cost-effectiveness in the application of each one. The decision to be made for each case of complicated diverticulitis often depends on the interaction and competence of the multidisciplinary team in charge.

Acetaminophen (APAP)-induced liver injury and acute liver failure is a significant clinical problem worldwide; in addition, APAP overdoses in animals or in cell culture are used as popular models to study drug-induced liver injury mechanisms and test therapeutic interventions. Early assumptions that APAP toxicity is caused by a single mechanism resulting in a defined mode of cell death in hepatocytes had to be questioned when over the years many different mechanisms and modes of cell death were reported. Although many of the contradictory results and conclusions reported over the years can be attributed to lack of understanding of established mechanisms, methodological problems, and misinterpretation of data, it is increasingly recognized that some of the reported differences in signaling mechanisms and even a switch in the mode of cell death can be caused by variations in the experimental conditions. In this review, examples will be discussed how experimental conditions (dose, solvent, etc.), the experimental system (species, strain, and substrain in vivo, cell type, and in vitro conditions), and also adaptive responses and off-target effects of genetic manipulations and chemical interventions, can impact the mechanisms of cell death. Given that the conditions will determine the results, it is therefore of critical importance to keep in mind the translational aspect of the experiments, i.e., the conditions relevant to the human pathophysiology. Only the full appreciation of these issues will lead to reproducible and clinically relevant results that advance our understanding of all facets of the human pathophysiology and identify clinically relevant therapeutic targets.

The epidemic of metabolic dysfunction-associated steatotic liver disease (MASLD) is increasingly growing worldwide. Thus, there is an urgent need for novel, non-invasive, and reliable biomarkers to replace liver biopsy for the diagnosis and prognosis of MASLD. Circulating peripheral blood mononuclear cells (PBMCs) are highly responsive to various stimuli and physiological changes. Beyond their immunomodulatory role, PBMC may act as metabolic sensors in several cardiometabolic disorders, including MASLD, with their metabolic programs shifting accordingly. Recent evidence suggests a link between impaired mitochondrial bioenergetics in PBMC and MASLD. Additionally, impaired mitochondrial respiration is intricately linked to the intracellular depletion of the oxidized form of nicotinamide adenine dinucleotide (NAD⁺) in various cell types. Accumulating preclinical and clinical data show that NAD⁺-increasing strategies may protect against MASLD by restoring intracellular NAD⁺ pools and improving mitochondrial performance. This review will focus on [i] the relevance of mitochondrial dysfunction, including impaired bioenergetics, in PBMC as a marker for the diagnosis and prognosis of MASLD, and [ii] the potential benefits of NAD⁺ precursors in MAFLD and their relationship with improved mitochondrial respiration in blood immune cells.

Hepatitis B virus (HBV) infection is a major risk factor of cirrhosis and hepatocellular carcinoma (HCC) worldwide. Pathogenesis of HBV-induced cirrhosis and HCC involves viral factors and virus-triggered local inflammatory and immune responses, the latter leading to progressive fibrosis, cirrhosis and carcinogenesis. Antiviral therapeutics suppress HBV replication and reduce the risks of cirrhosis and HCC. We discuss the current knowledge on the pathogenesis of HBV-induced cirrhosis and HCC, focusing on mechanisms of current and emerging antiviral therapeutics.

Microsatellite unstable (MSI) colorectal cancer (CRC) tumors have a high mutational load (particularly frame-shift mutations) that creates numerous neoantigens that are presented to major histocompatibility complex molecules and recognized by T cells. Consequently, MSI tumors have a higher presence of tumor-infiltrating lymphocytes than mismatch repair-proficient tumors. Colorectal cancer patients with MSI constitute a rare group of immune checkpoint inhibitor (ICI)-responsive patients. Nonetheless, complete radiological responders comprise between 3% and 16% of MSI advanced CRC patients, which compares poorly with the 45% to 87% rate of pathological complete response in early MSI CRC patients treated with ICIs. In this review, we address the efficacy of current ICIs and the biological differences between early and advanced MSI CRC to potentially increase the efficacy of ICIs in both settings.

Liver inflammation, injury, and hepatic cell death are caused by external agents (viruses, bacteria, drugs, alcohol, etc.) along with the genetic susceptibility of an individual. Persistent activation of the fibrogenic response in cells leads to liver fibrosis which in turn progresses to cirrhosis and cancer. The dysregulation of the immune system generates reactive oxygen species which in turn induce necrosis of hepatocytes. This process activates hepatic stellate cells and myofibroblasts to produce a huge quantity of collagens, alpha-smooth muscle actin, and extracellular matrix deposition in liver parenchyma. Due to the multifactorial nature of this disease, conventional therapies increasingly attempted combinatorial therapy or polytherapy to target multiple mechanistic sites in order to prevent entry into further complicated irreversible stages. Despite advancements in conventional therapy, several cases aggravate fibrosis (grade 3 to 4) and cirrhosis. The inconsistency in treatment outcomes and limited organ donors for liver transplantation have led to an ever-increasing and challenging demand for alternative therapies. In this review, we analyze the mechanism and causative factors of liver diseases, conventional mode, and alternative therapeutic options. The central to liver diseases are immune dysregulation, hence bioactive agents with immunomodulatory properties should be searched and exploited to meet therapeutic needs. Mesenchymal stem cells (MSCs) with their specialized anti-inflammatory and immunomodulatory properties could be utilized as an effective alternative therapeutic candidate in treating inflammatory liver diseases. MSC-derived exosome further provides an additional immunomodulatory option that could work in tandem with MSC in a synergistic form. In this series, we have reviewed preconditioned and genetically edited MSCs to augment homing, proliferation, and differentiation. Importantly, all the clinical challenges should be noted and addressed before stem cell cytotherapy should be considered safe and effective for patients with liver diseases. Published literature indicated that MSC therapy has the potential to substitute conventional options in the treatment of high-grade fibrosis and cirrhosis.