TGF-β1 and TGF-β2 abundance in liver diseases of mice and men

TGF-β1 is a major player in chronic liver diseases promoting fibrogenesis and tumorigenesis through various mechanisms. The expression and function of TGF-β2 have not been investigated thoroughly in liver disease to date. In this paper, we provide evidence that TGF-β2 expression correlates with fibrogenesis and liver cancer development. Using quantitative realtime PCR and ELISA, we show that TGF-β2 mRNA expression and secretion increased in murine HSCs and hepatocytes over time in culture and were found in the human-derived HSC cell line LX-2. TGF-β2 stimulation of the LX-2 cells led to upregulation of the TGF-β receptors 1, 2, and 3, whereas TGF-β1 treatment did not alter or decrease their expression. In liver regeneration and fibrosis upon CCl4 challenge, the transient increase of TGF-β2 expression was accompanied by TGF-β1 and collagen expression. In bile duct ligation-induced fibrosis, TGF-β2 upregulation correlated with fibrotic markers and was more prominent than TGF-β1 expression. Accordingly, MDR2-KO mice showed significant TGF-β2 upregulation within 3 to 15 months but minor TGF-β1 expression changes. In 5 of 8 hepatocellular carcinoma (HCC)/hepatoblastoma cell lines, relatively high TGF-β2 expression and secretion were observed, with some cell lines even secreting more TGF-β2 than TGF-β1. TGF-β2 was also upregulated in tumors of TGFα/cMyc and DEN-treated mice. The analysis of publically available microarray data of 13 human HCC collectives revealed considerable upregulation of TGF-β2 as compared to normal liver. Our study demonstrates upregulation of TGF-β2 in liver disease and suggests TGF-β2 as a promising therapeutic target for tackling fibrosis and HCC

Expression analysis and functional studies of Bone Morphogenetic Protein and Activin Membrane-Bound Inhibitor (BAMBI) in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a complex disease with a poor prognosis which has increased the survival rates on account to the improvement in patient stratification and the introduction of new targeted therapies. However, there is still an urgent need for early diagnostic markers and personalized treatments in order to enhance the survival and reduce HCC´s recurrence. BAMBI, a transmembrane glycoprotein that regulates several biological activities through TGF-β signalling inhibition, was shown to have increased expression levels in colorectal, gastric and ovarian cancers where it correlated with metastasis, invasion and poor prognosis. Although in HCC BAMBI was reported to be upregulated, no molecular and functional studies were done so far to unravel its participation in hepatocarcinogenesis. Our meta-analysis in publicly available HCC data cohorts confirmed BAMBI overexpression in 78% of HCC patients (n=803) being upregulated and also present in cirrhotic samples and the tumour stroma. Further, BAMBI expression was also confirmed in MDR2-KO and DEN mice. Parallel to these results, the immunohistochemical (IHC) staining of a human HCC tissue microarray revealed the upregulation in 76% of patients with positive staining for BAMBI in the surrounding tissues. In HCC cell lines, BAMBI expression appeared only in the cells that present early TGF-β signature (Hep3B, HepG2 and HUH7), which corresponds to an epithelial phenotype and less aggressiveness. BAMBI knockdown in Hep3B cells produced a strong TGF-β-mediated apoptosis and reduced cell proliferation. In less differentiated HLE cells with low intrinsic BAMBI expression, BAMBI overexpression enhanced proliferation, migration and invasion in vitro. Immunoblot assays additionally show BAMBI expression dependent modulation of ERK1/2, NFκB, Wnt/β-catenin, AKT and JNK/p38 MAPK pathways. In conclusion, we report that bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) is upregulated in livers of HCC patients and differently expressed in HCC cell models. High BAMBI expression is blocking TGFβ-mediated apoptosis and increases proliferation in epithelial HCC cells, and reduces proliferation, migration and invasion with impact on Wnt/β-catenin, ERK1/2, AKT, NFκB and JNK/p38 MAPK pathways in mesenchymal HCC. The activation of these functions depends on the TGF-β signature stage and cell context. We postulate BAMBI as a potential target in personalized therapies for human hepatocellular carcinoma

TGF-β1 and TGF-β2 abundance in liver diseases of mice and men

TGF-β1 is a major player in chronic liver diseases promoting fibrogenesis and tumorigenesis through various mechanisms. The expression and function of TGF-β2 have not been investigated thoroughly in liver disease to date. In this paper, we provide evidence that TGF-β2 expression correlates with fibrogenesis and liver cancer development. Using quantitative realtime PCR and ELISA, we show that TGF-β2 mRNA expression and secretion increased in murine HSCs and hepatocytes over time in culture and were found in the human-derived HSC cell line LX-2. TGF-β2 stimulation of the LX-2 cells led to upregulation of the TGF-β receptors 1, 2, and 3, whereas TGF-β1 treatment did not alter or decrease their expression. In liver regeneration and fibrosis upon CCl4 challenge, the transient increase of TGF-β2 expression was accompanied by TGF-β1 and collagen expression. In bile duct ligation-induced fibrosis, TGF-β2 upregulation correlated with fibrotic markers and was more prominent than TGF-β1 expression. Accordingly, MDR2-KO mice showed significant TGF-β2 upregulation within 3 to 15 months but minor TGF-β1 expression changes. In 5 of 8 hepatocellular carcinoma (HCC)/hepatoblastoma cell lines, relatively high TGF-β2 expression and secretion were observed, with some cell lines even secreting more TGF-β2 than TGF-β1. TGF-β2 was also upregulated in tumors of TGFα/cMyc and DEN-treated mice. The analysis of publically available microarray data of 13 human HCC collectives revealed considerable upregulation of TGF-β2 as compared to normal liver. Our study demonstrates upregulation of TGF-β2 in liver disease and suggests TGF-β2 as a promising therapeutic target for tackling fibrosis and HCC

TGF-β2 silencing to target biliary-derived liver diseases

Objective TGF-beta 2 (TGF-beta, transforming growth factor beta), the less-investigated sibling of TGF-beta 1, is deregulated in rodent and human liver diseases. Former data from bile duct ligated and MDR2 knockout (KO) mouse models for human cholestatic liver disease suggested an involvement of TGF-beta 2 in biliary-derived liver diseases. Design As we also found upregulated TGFB2 in liver tissue of patients with primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC), we now fathomed the positive prospects of targeting TGF-beta 2 in early stage biliary liver disease using the MDR2-KO mice. Specifically, the influence of TgfB2 silencing on the fibrotic and inflammatory niche was analysed on molecular, cellular and tissue levels. Results TgfB2-induced expression of fibrotic genes in cholangiocytes and hepatic stellate cellswas detected. TgfB2 expression in MDR2-KO mice was blunted using TgfB2-directed antisense oligonucleotides (AON). Upon AON treatment, reduced collagen deposition, hydroxyproline content and aSMA expression as well as induced PparG expression reflected a significant reduction of fibrogenesis without adverse effects on healthy livers. Expression analyses of fibrotic and inflammatory genes revealed AON-specific regulatory effects on Ccl3, Ccl4, Ccl5, Mki67 and Notch3 expression. Further, AON treatment of MDR2-KO mice increased tissue infiltration by F4/80-positive cells including eosinophils, whereas the number of CD45-positive inflammatory cells decreased. In line, TGFB2 and CD45 expression correlated positively in PSC/PBC patients and localised in similar areas of the diseased liver tissue. Conclusions Taken together, our data suggest a new mechanistic explanation for amelioration of fibrogenesis by TGF-beta 2 silencing and provide a direct rationale for TGF-beta 2-directed drug development

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population