Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related mortality worldwide. We previously showed that a tumor/cancer stem cell (CSC) marker, doublecortin-like kinase (DCLK1) positively regulates hepatitis C virus (HCV) replication, and promotes tumor growth in colon and pancreas. Here, we employed transcriptome analysis, RNA interference, tumor xenografts, patient's liver tissues and hepatospheroids to investigate DCLK1-regulated inflammation and tumorigenesis in the liver. Our studies unveiled novel DCLK1-controlled feed-forward signaling cascades involving calprotectin subunit S100A9 and NFκB activation as a driver of inflammation. Validation of transcriptome data suggests that DCLK1 co-expression with HCV induces BRM/SMARCA2 of SW1/SNF1 chromatin remodeling complexes. Frequently observed lymphoid aggregates including hepatic epithelial and stromal cells of internodular septa extensively express DCLK1 and S100A9. The DCLK1 overexpression also correlates with increased levels of S100A9, c-Myc, and BRM levels in HCV/HBV-positive patients with cirrhosis and HCC. DCLK1 silencing inhibits S100A9 expression and hepatoma cell migration. Normal human hepatocytes (NHH)-derived spheroids exhibit CSC properties. These results provide new insights into the molecular mechanism of the hepatitis B/C-virus induced liver inflammation and tumorigenesis via DCLK1-controlled networks. Thus, DCLK1 appears to be a novel therapeutic target for the treatment of inflammatory diseases and HCC.

Evans syndrome (ES) is a rare condition characterised by the combination of autoimmune haemolytic anaemia and immune thrombocytopenia (ITP). While the precise pathophysiology is not entirely understood, it is thought that dysregulation of the immune system is a primary contributor to the condition. ES has been observed in viral infections including hepatitis C, cytomegalovirus, varicella zoster and Epstein-Barr viruses. [1][2][3][4] Initial cases of coronavirus disease 2019 (COVID-19) were first described in early December 2019 and has now spread to a global pandemic. While knowledge about COVID-19 continues to evolve, clinicians have reported haematological complications associated with the virus. Presence of lymphopenia has been commonly reported in 35-40% of cases and appears to be associated with the development of acute respiratory distress syndrome. [5][6][7] Thrombocytopenia and coagulopathies, including disseminated intravascular coagulation, have also been reported in cases of COVID-19, which were associated with more severe disease. 8,9 Here, we present the first case, to our knowledge, of COVID-19-associated ES and discuss its unique management issues.A 39-year-old man presented to the emergency department in late March 2020 with one day of haemoptysis and epistaxis in the setting of sore throat, productive cough, fevers, chills and dyspnoea lasting about 1 week. On evaluation, he was found to be febrile, tachycardic and tachypneic. Physical examination was notable for dried blood in the oropharynx and nares, as well as a blood blister in the mouth. He had no petechiae, ecchymoses or rash. Laboratory assessments demonstrated a leucocyte count of 11 000 cells/ µl, haemoglobin of 156 g/l and platelet count of 3000 cells/ µl. The neutrophil count was 8700 cells/µl, and lymphocyte count was 1700 cells/µl. Haemolysis laboratories were negative, and there were no schistocytes nor microspherocytes on peripheral blood smear. There was no infiltrate on chest X-ray. Rapid polymerase chain reaction assay for COVID-19 later returned a positive a result.On admission, the patient developed worsening bleeding with haematemesis, melena and haematochezia, associated with a haemoglobin decrease to 64 g/l. Intravenous proton pump inhibitor therapy was initiated, as well as daily intravenous immunoglobulin (IVIG) therapy for presumed ITP secondary to COVID-19. Glucocorticoids were not administered, as organisations such as the Centers for Disease Control (CDC) and World Health Organization (WHO) recommended against the use of glucocorticoids in patients with COVID-19. 10,11 On day 5, the platelet count recovered to 52 cells/µl with resolution of bleeding. By day 6, platelets were 308 cells/µl, haemoglobin was stable at 76 g/l, and the patient was discharged.

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. Chronic hepatitis C virus (HCV) infection causes induction of several tumor/cancer stem cell (CSC) markers and is known to be a major risk factor for development of HCC. Therefore, drugs that simultaneously target viral replication and CSC properties are needed for a risk-free treatment of advanced stage liver diseases including HCC. Here, we demonstrated that (Z)-3,5,4’-trimethoxystilbene (Z-TMS) exhibits potent anti-tumor and anti-HCV activities without exhibiting cytotoxicity to human hepatocytes in vitro or in mice livers. Diethylnitrosamine (DEN)/carbon tetrachloride (CCl4) extensively induced expression of DCLK1 (a CSC marker) in the livers of C57BL/6 mice following hepatic injury. Z-TMS exhibited hepatoprotective effects against DEN/CCl4-induced injury by reducing DCLK1 expression and improving histological outcomes. The drug caused bundling of DCLK1 with microtubules and blocked cell cycle progression at G2/M phase in hepatoma cells via downregulation of CDK1, induction of p21cip1/waf1 expression, and inhibition of Akt (Ser473) phosphorylation. Z-TMS also inhibited proliferation of erlotinib-resistant lung adenocarcinoma cells (H1975) bearing the T790M EGFR mutation most likely by promoting autophagy and nuclear fragmentation. In conclusion, Z-TMS appears to be a unique therapeutic agent targeting HCV and concurrently eliminating cells with neoplastic potential during chronic liver diseases including HCC. It may also be a valuable drug for targeting drug-resistant carcinomas and cancers of the lungs, pancreas, colon, and intestine in which DCLK1 is involved in tumorigenesis.

Chronic liver injury is a risk factor for cirrhosis and hepatocellular carcinoma (HCC). The molecular mechanisms that regulate the decision between normal injury repair and neoplastic initiation are unclear. Doublecortin-like kinase 1 (DCLK1), a tumor stem cell marker, is induced during cirrhosis and HCC. Here, we demonstrate that DCLK1-overexpressing primary human hepatocytes formed spheroids in suspension cultures. Spheroids derived from DCLK1-overexpressing hepatoma cells showed high level expression of active β-catenin, α-fetoprotein, and SOX9, suggesting that DCLK1 overexpression induces clonogenicity and dedifferentiated phenotypes in hepatoma cells. DCLK1 overexpression in hepatoma cells also increased phosphorylation of GSK-3β at Ser 9. This was associated with an induction of a 48-kDa active β-catenin with a preserved hypophosphorylated N-terminus that interacted with nuclear TCF-4 resulting in luciferase reporter activity and cyclin D1 expression. DCLK1 downregulation inhibited 48-kDa β-catenin expression. The proteasome inhibitor bortezomib did not block the 48-kDa β-catenin, instead, caused a threefold accumulation, suggesting a proteasome-independent mechanism. Liver tissues from patients with cirrhosis and HCC revealed epithelial co-staining of DCLK1 and active β-catenin, and cleaved E-cadherin. Repopulated DCLK1overexpressing primary human hepatocytes in humanized FRG mouse livers demonstrated active β-catenin. In conclusion, DCLK1 regulates oncogenic signaling and clonogenicity of hepatocytes by a novel non-canonical/atypical β-catenin-dependent mechanism. Hepatocellular carcinoma (HCC) is the second most common cause of cancer-related mortality and accounts for approximately 745,000 deaths per year worldwide 1. Chronic liver injury due to hepatitis B/C viral infections (HBV and HCV), metabolic disorders, and alcohol are the major risk factors for HCC 2. Recent reports using genetic lineage tracing models have demonstrated that mature hepatocytes are the cells of origin in injuryinduced HCC 3. Tumorigenesis in the liver is attributable to hepatocyte plasticity, defined as the ability of the mature hepatocytes to undergo phenotype change usually by dedifferentiation or transdifferentiation into a preneoplastic precursor cell-type 4-6. The existing paradigm that hepatic facultative stem/progenitor cells are activated to produce different cell types during liver injury has been challenged in favor of hepatocyte plasticity 5,7,8. This intuitive concept rests upon observations that mature hepatocytes retain the capacity to undergo rapid division

Liver diseases are the fourth leading cause of mortality among adults in the United States. Patients with chronic liver diseases such as viral hepatitis, fibrosis, and cirrhosis have significantly higher risks of developing hepatocellular carcinoma (HCC). With a dismal five-year survival rate of 11%, HCC is the third most common cause of cancer-related deaths worldwide. Regardless of the underlying cause, late presentation and a lack of effective therapy are the major impediments for successful treatment of HCC. Therefore, there is a considerable interest in developing new strategies for the prevention and treatment of chronic liver diseases at the early stages. Cancer stem cells (CSCs), a small cell subpopulation in a tumor, exhibit unlimited self-renewal and differentiation capacity. These cells are believed to play pivotal roles in the initiation, growth, metastasis, and drug-resistance of tumors. In this review, we will briefly discuss pivotal roles of the CSC marker doublecortin-like kinase 1 (DCLK1) in hepatic tumorigenesis. Recent evidence suggests that anti-DCLK1 strategies hold promising clinical potential for the treatment of cancers of the liver, pancreas, and colon.