Serial changes of serum growth factor levels and liver regeneration after partial hepatectomy in healthy humans

Reversible expansion of tissue macrophages in response to macrophage colony-stimulating factor (CSF1) transforms systemic lipid and carbohydrate metabolism

Macrophages regulate metabolic homeostasis in health and disease. Macrophage colony-stimulating factor (CSF1)-dependent macrophages contribute to homeostatic control of the size of the liver. This study aimed to determine the systemic metabolic consequences of elevating circulating CSF1. Acute administration of a CSF1-Fc fusion protein to mice led to monocytosis, increased resident tissue macrophages in the liver and all major organs, and liver growth. These effects were associated with increased hepatic glucose uptake and extensive mobilization of body fat. The impacts of CSF1 on macrophage abundance, liver size, and body composition were rapidly reversed to restore homeostasis. The effects of CSF1 on metabolism were independent of several known endocrine regulators and did not impact the physiological fasting response. Analysis using implantable telemetry in metabolic cages revealed progressively reduced body temperature and physical activity with no change in diurnal food intake. These results demonstrate the existence of a dynamic equilibrium between CSF1, the mononuclear phagocyte system, and control of liver-to-body weight ratio, which in turn controls systemic metabolic homeostasis. This novel macrophage regulatory axis has the potential to promote fat mobilization, without changes in appetence, which may have novel implications for managing metabolic syndrome.NEW & NOTEWORTHY CSF1 administration expands tissue macrophages, which transforms systemic metabolism. CSF1 drives fat mobilization and glucose uptake to support liver growth. The effects of CSF1 are independent of normal hormonal metabolic regulation. The effects of CSF1 are rapidly reversible, restoring homeostatic body composition. CSF1-dependent macrophages and liver size are coupled in a dynamic equilibrium.

The Impact of Chemotherapy and Transforming Growth Factor-β1 in Liver Regeneration after Hepatectomy among Colorectal Cancer Patients

An ongoing debate surrounds the impact of chemotherapy on post-hepatectomy liver regeneration in patients with colorectal cancer liver metastases (CRLM), with unclear regulatory mechanisms. This study sought to delve into liver regeneration post-resection in CRLM patients, specifically examining the roles of hepatocyte growth factor (HGF) and transforming growth factor β1 (TGF-β1). In this longitudinal observational study, 17 patients undergoing major liver resection for CRLM and 17 with benign indications as controls were enrolled. Liver regeneration within 30 postoperative days was assessed via CT, considering clinicopathological characteristics, liver enzymes, liver stiffness by elastography, and the impact of HGF and TGF-β1 on liver regeneration. The results revealed that the control group exhibited significantly higher mean liver regeneration volume (200 ± 180 mL) within 30 days postoperatively compared to the CRLM group (72 ± 154 mL); p = 0.03. Baseline alkaline phosphatase (AP) and TGF-β1 blood levels were notably higher in the CRLM group. Immunohistochemical analysis indicated a higher proportion of CRLM patients with high TGF-β1 expression in liver tissues compared to the control group (p = 0.034). Correlation analysis showed that resected liver volume, baseline plasma HGF, AP, and albumin levels significantly correlated with liver regeneration volume. However, in multivariable analysis, only resected liver volume (β: 0.31; 95% CI: 0.14-0.47, p = 0.01) remained significant. In conclusion, this study highlights compromised liver regeneration in CRLM patients post-chemotherapy. Additionally, these patients exhibited lower serum TGF-β1 levels and reduced TGF-β1 expression in liver tissue, suggesting TGF-β1 involvement in mechanisms hindering liver regeneration capacity following major resection after chemotherapy.

Contemporaneous Perioperative Inflammatory and Angiogenic Cytokine Profiles of Surgical Breast, Colorectal, and Prostate Cancer Patients: Clinical Implications

Surgery-induced tumor growth acceleration and synchronous metastatic growth promotion have been observed for decades. Surgery-induced wound healing, orchestrated through growth factors, chemokines, and cytokines, can negatively impact patients harboring residual or metastatic disease. We provide detailed clinical evidence of this process in surgical breast, prostate, and colorectal cancer patients. Plasma samples were analyzed from 68 cancer patients who had not received treatment before surgery or adjuvant therapy until at least four weeks post-surgery. The levels of plasma cytokines, chemokines, and growth factors were simultaneously quantified and profiled using multiplexed immunoassays for eight time points sampled per patient. The immunologic processes are induced immediately after surgery in patients, characterized by a drastic short-term shift in the expression levels of pro-inflammatory and angiogenic molecules and cytokines. A rapid and significant spike in circulating plasma levels of hepatocyte growth factor (HGF), interleukin-6 (IL-6), placental growth factor (PLGF), and matrix metalloproteinase-9 (MMP-9) after surgery was noted. The rise in these molecules was concomitant with a significant drop in transforming growth factor-β1 (TGF-β1), platelet-derived growth factor (PDGF-AB/BB), insulin-like growth factor-1 (IGF-1), and monocyte chemoattractant protein-2 (MCP-2). If not earlier, each plasma analyte was normalized to baseline levels within 1-2 weeks after surgery, suggesting that surgical intervention alone was responsible for these effects. The effects of surgical tumor removal on disrupting the pro-inflammatory and angiogenic plasma profiles of cancer patients provide evidence for potentiating malignant progression. Our findings indicate a narrow therapeutic window of opportunity after surgery to prevent disease recurrence.

Predicting liver regeneration following major resection

Breakdown of synthesis, excretion and detoxification defines liver failure. Post-hepatectomy liver failure (PHLF) is specific for liver resection and a rightfully feared complication due to high lethality and limited therapeutic success. Individual cytokine and growth factor profiles may represent potent predictive markers for recovery of liver function. We aimed to investigate these profiles in post-hepatectomy regeneration. This study combined a time-dependent cytokine and growth factor profiling dataset of a training (30 patients) and a validation (14 patients) cohorts undergoing major liver resection with statistical and predictive models identifying individual pathway signatures. 2319 associations were tested. Primary hepatocytes isolated from patient tissue samples were stimulated and their proliferation was analysed through DNA content assay. Common expression trajectories of cytokines and growth factors with strong correlation to PHLF, morbidity and mortality were identified despite highly individual perioperative dynamics. Especially, dynamics of EGF, HGF, and PLGF were associated with mortality. PLGF was additionally associated with PHLF and complications. A global association-network was calculated and validated to investigate interdependence of cytokines and growth factors with clinical attributes. Preoperative cytokine and growth factor signatures were identified allowing prediction of mortality following major liver resection by regression modelling. Proliferation analysis of corresponding primary human hepatocytes showed associations of individual regenerative potential with clinical outcome. Prediction of PHLF was possible on as early as first postoperative day (POD1) with AUC above 0.75. Prediction of PHLF and mortality is possible on POD1 with liquid-biopsy based risk profiling. Further utilization of these models would allow tailoring of interventional strategies according to individual profiles.

HGF/c-Met: A Key Promoter in Liver Regeneration

Hepatocyte growth factor (HGF) is a peptide-containing multifunctional cytokine that acts on various epithelial cells to regulate cell growth, movement and morphogenesis, and tissue regeneration of injured organs. HGF is sequestered by heparin-like protein in its inactive form and is widespread in the extracellular matrix of most tissues. When the liver loses its average mass, volume, or physiological and biochemical functions due to various reasons, HGF binds to its specific receptor c-Met (cellular mesenchymal-epithelial transition) and transmits the signals into the cells, and triggers the intrinsic kinase activity of c-Met. The downstream cascades of HGF/c-Met include JAK/STAT3, PI3K/Akt/NF-κB, and Ras/Raf pathways, affecting cell proliferation, growth, and survival. HGF has important clinical significance for liver fibrosis, hepatocyte regeneration after inflammation, and liver regeneration after transplantation. And the development of HGF as a biological drug for regenerative therapy of diseases, that is, using recombinant human HGF protein to treat disorders in clinical trials, is underway. This review summarizes the recent findings of the HGF/c-Met signaling functions in liver regeneration.

Value of Liver Function Tests in Cirrhosis

The liver comprises both parenchymal and non-parenchymal cells with varying functions. Cirrhosis is often complicated by the development of portal hypertension and its associated complications. Hence, assessment of liver in cirrhosis should include assessment of its structural, function of both hepatic and non-hepatic tissue and haemodynamic assessment of portal hypertension. There is no single test that can evaluate all functions of liver and assess prevalence and severity of portal hypertension. Commonly available tests like serum bilirubin, liver enzymes (alanine [ALT] and aspartate aminotransferase [AST], serum alkaline phosphatase [ALP], gamma glutamyl transpeptidase [GGT]), serum albumin and prothrombin time for assessment of liver functions partly assess liver functions. quantitative liver functions like indocyanine clearance tests [ICG-K], methacetin breath test [MBT] were developed to assess dynamic status of liver but has its own limitation and availability. Imaging based assessment of liver by transient elastography, MRI based 99 mTc-coupled asialoglycoprotein mebrofenin scan help the clinician to assess liver function, functional volume of liver left after surgery and portal hypertension [PH]. Hepatic venous pressure gradient still remains the gold standard for the assessment of portal hypertension but is invasive and not available in all centres. Combinations of blood parameters in form of various indices like fibrosis score of 4 [FIB-4], Lok index, scores like model for end stage liver disease (MELD) and Child-Turcotte Pugh score are commonly used for assessing liver function in clinical practice.

Technique of vessel-skeletonized parenchyma-sparing hepatectomy for the oncological treatment of bilobar colorectal liver metastases

BACKGROUND

To aid in the oncological management of multiple bilobar colorectal liver metastases (CRLMs), we describe a new surgical procedure, VEssel-Skeletonized PArenchyma-sparing Hepatectomy (VESPAH).

STUDY DESIGN

Of 152 patients with CRLMs treated with hepatectomy, 33 patients had multiple bilobar liver metastases (≥8 liver metastases); their surgical procedures and clinical outcomes were retrospectively summarized and compared between those who underwent VESPAH and those who underwent major hepatectomy (Major Hx).

RESULTS

Of the 33 patients, 20 patients were resected by VESPAH (the VESPAH group) and 13 patients by major hepatectomy (Major Hx group). The median number of CRLMs was 13 (range, 8-53) in the VESPAH group and 10 (range, 8-41) in the Major Hx group (P=0.511). No operative mortality nor severe morbidity was observed in either group. The VESPAH group showed earlier recovery of remnant liver function after surgery than the Major Hx group; the incidence of grade B/C post hepatectomy liver failure was 5% in the VESPAH group and 38% in the Major Hx group, P=0.048). Intrahepatic tumor recurrence was confirmed in 14 (70%) and 7 (54%) patients in the VESPAH and Major Hx groups, respectively (P=0.416). There was no significant difference in median overall survival (OS) after hepatectomy between the two groups; the median OS was 47 months in the VESPAH group and 33 months in the Major Hx group (P=0.481). The VESPAH group showed the higher induction rate of adjuvant chemotherapy within 2 months after surgery (P=0.002) and total number of repeat hepatectomy for intrahepatic recurrence (P=0.060) than the Major Hx group.

CONCLUSIONS

VESPAH enables us to clear surgical navigation by hepatic vessel skeletonization and may enhance patient tolerability of not only adjuvant chemotherapy but also repeat hepatectomies during the patients' lifetimes.

Association between immunologic markers and cirrhosis in individuals with chronic hepatitis B

Host immune response and chronic inflammation associated with chronic hepatitis B virus (HBV) infection play a key role in the pathogenesis of liver diseases such as cirrhosis and hepatocellular carcinoma (HCC). We sampled 175 HCC, 117 cirrhotic and 165 non-cirrhotic controls from a prospective cohort study of chronically HBV-infected individuals. Multivariable polytomous logistic regression and canonical discriminant analysis (CDA) were used to compare baseline plasma levels for 102 markers in individuals who developed cirrhosis vs. controls and those who developed HCC vs. cirrhosis. Leave-one-out cross validation was used to generate receiver operating characteristic curves to compare the predictive ability of marker groups. After multivariable adjustment, HGF (Q4v1OR: 3.74; p-trend = 0.0001), SLAMF1 (Q4v1OR: 4.07; p-trend = 0.0001), CSF1 (Q4v1OR: 3.00; p-trend = 0.002), uPA (Q4v1OR: 3.36; p-trend = 0.002), IL-8 (Q4v1OR: 2.83; p-trend = 0.004), and OPG (Q4v1OR: 2.44; p-trend = 0.005) were all found to be associated with cirrhosis development compared to controls; these markers predicted cirrhosis with 69% accuracy. CDA analysis identified a nine marker model capable of predicting cirrhosis development with 79% accuracy. No markers were significantly different between HCC and cirrhotic participants. In this study, we assessed immunologic markers in relation to liver disease in chronically-HBV infected individuals. While validation in required, these findings highlight the importance of immunologic processes in HBV-related cirrhosis.

The Current Status of Granulocyte-Colony Stimulating Factor to Treat Acute-on-Chronic Liver Failure

Patients with acute-on-chronic liver failure (ACLF) have a devastating prognosis and therapeutic options are limited. Granulocyte-colony stimulating factor (G-CSF) mobilizes immune and stem cells and possess immune-modulatory and proregenerative capacities. In this review, we aim to define the current evidence for the treatment with G-CSF in end-stage liver disease. Several smaller clinical trials in patients with different severity grades of end-stage liver disease have shown that G-CSF improves survival and reduces the rate of complications. Adequately powered multicenter European trials could not confirm these beneficial effects. In mouse models of ACLF, G-CSF increased the toll-like receptor (TLR)-mediated inflammatory response which led to an increase in mortality. Adding a TLR4 signaling inhibitor allowed G-CSF to unfold its proregenerative properties in these ACLF models. These data suggest that G-CSF requires a noninflammatory environment to exert its protective properties.

Influence of cytokines, circulating markers and growth factors on liver regeneration and post-hepatectomy liver failure: a systematic review and meta-analysis

The pathophysiology of post-hepatectomy liver failure is not entirely understood but is rooted in the disruption of normal hepatocyte regeneration and homeostasis. Current investigations of post-hepatectomy liver failure and regeneration are focused on evaluation of circulating hepatic function parameters (transaminases, cholestasis, and coagulation parameters), volumetry and hepatic hemodynamics. However, identification of biochemical factors associated with regeneration and post hepatectomy liver failure is crucial for understanding the pathophysiology and identification of patients at risk. The objective of the present systematic review was to identify circulating factors associated with liver regeneration and post hepatectomy liver failure in patients undergoing hepatectomy. The quantitative analysis was intended if studies provided sufficient data. Electronic databases (MEDLINE via PubMed, Web of Knowledge, Cochrane Library and WHO International Clinical Trials Registry Platform) were searched for publications on cell signaling factors in liver regeneration and post-hepatectomy liver failure following liver resection in clinical setting. No date restriction was given. No language restriction was used. Studies were assessed using MINORS. This study was registered at PROSPERO (CRD42020165384) prior to data extraction. In total 1953 publications were evaluated for titles and abstracts after exclusion of duplicates. Full texts of 167 studies were further evaluated for inclusion. 26 articles were included in the review and 6 publications were included in the meta-analyses. High levels of serum hyaluronic acid even preoperatively are associated with PHLF but especially increased levels early after resection are predictive of PHLF with high sensitivity and specificity. Postoperative elevation of HA to levels between 100 and 500 ng/ml is increased the risk for PHLF ([OR] = 246.28, 95% [CI]: 11.82 to 5131.83; p = 0.0004) Inteleukin-6 levels show contradicting result in association with organ dysfunction. HGF positively correlates with liver regeneration. Overall, due to heterogeneity, scarcity, observational study design and largely retrospective analysis, the certainty of evidence, assessed with GRADE, is very low. High levels of serum hyaluronic acid show a strong association with PHLF and increased levels after resection are predictive of PHLF with high sensitivity and specificity, even on POD1. Interleukin-6 levels need to be studied further due to contradictive results in association with organ dysfunction. For HGF, no quantitative analysis could be made. Yet, most studies find positive correlation between high HGF levels and regeneration. Prospective studies investigating HGF and other growth factors, hyaluronic acid and interleukins 1 and 6 in correlation with liver regeneration measured sequentially through e.g. volumetry, and liver function parameters, preferably expanding the analysis to include dynamic liver function tests, are needed to sufficiently illustrate the connection between biomolecule levels and clinical outcomes.

Unraveling the Role of Leptin in Liver Function and Its Relationship with Liver Diseases

Since its discovery twenty-five years ago, the fat-derived hormone leptin has provided a revolutionary framework for studying the physiological role of adipose tissue as an endocrine organ. Leptin exerts pleiotropic effects on many metabolic pathways and is tightly connected with the liver, the major player in systemic metabolism. As a consequence, understanding the metabolic and hormonal interplay between the liver and adipose tissue could provide us with new therapeutic targets for some chronic liver diseases, an increasing problem worldwide. In this review, we assess relevant literature regarding the main metabolic effects of leptin on the liver, by direct regulation or through the central nervous system (CNS). We draw special attention to the contribution of leptin to the non-alcoholic fatty liver disease (NAFLD) pathogenesis and its progression to more advanced stages of the disease as non-alcoholic steatohepatitis (NASH). Likewise, we describe the contribution of leptin to the liver regeneration process after partial hepatectomy, the mainstay of treatment for certain hepatic malignant tumors.

Markers of liver regeneration-the role of growth factors and cytokines: a systematic review

Background

Post-hepatectomy liver failure contributes significantly to postoperative mortality after liver resection. The prediction of the individual risk for liver failure is challenging. This review aimed to provide an overview of cytokine and growth factor triggered signaling pathways involved in liver regeneration after resection.

Methods

MEDLINE and Cochrane databases were searched without language restrictions for articles from the time of inception of the databases till March 2019. All studies with comparative data on the effect of cytokines and growth factors on liver regeneration in animals and humans were included.

Results

Overall 3.353 articles comprising 40 studies involving 1.498 patients and 101 animal studies were identified and met the inclusion criteria. All included trials on humans were retrospective cohort/observational studies. There was substantial heterogeneity across all included studies with respect to the analyzed cytokines and growth factors and the described endpoints.

Conclusion

High-level evidence on serial measurements of growth factors and cytokines in blood samples used to predict liver regeneration after resection is still lacking. To address the heterogeneity of patients and potential markers, high throughput serial analyses may offer a method to predict an individual’s regenerative potential in the future.

New Insights into the Liver-Visceral Adipose Axis During Hepatic Resection and Liver Transplantation

In the last decade, adipose tissue has emerged as an endocrine organ with a key role in energy homeostasis. In addition, there is close crosstalk between the adipose tissue and the liver, since pro- and anti-inflammatory substances produced at the visceral adipose tissue level directly target the liver through the portal vein. During surgical procedures, including hepatic resection and liver transplantation, ischemia–reperfusion injury induces damage and regenerative failure. It has been suggested that adipose tissue is associated with both pathological or, on the contrary, with protective effects on damage and regenerative response after liver surgery. The present review aims to summarize the current knowledge on the crosstalk between the adipose tissue and the liver during liver surgery. Therapeutic strategies as well as the clinical and scientific controversies in this field are discussed. The different experimental models, such as lipectomy, to evaluate the role of adipose tissue in both steatotic and nonsteatotic livers undergoing surgery, are described. Such information may be useful for the establishment of protective strategies aimed at regulating the liver–visceral adipose tissue axis and improving the postoperative outcomes in clinical liver surgery.

Impact of donor age on liver regeneration and function following adult living donor liver transplantation

The aim of the present study was to evaluate the impact of donor age on liver function and regeneration following living donor liver transplantation. Donors were divided into an elderly donor group (age >50 years old; n=8) and a young donor group (age <30 years old; n=35). The recipients were also divided into an elderly group (age >50 years old; n=5) and a young group (age <30 years old; n=25). Alanine aminotransferase, aspartate aminotransferase, total bilirubin (TB) and prothrombin time were recorded 1-5 days postoperatively. The liver regeneration ratio (LRR) was recorded 7 and 15 days postoperatively in donors and at 0.5, 1, 3 and 6 months postoperatively in recipients by contrast-enhanced multi-slice spiral computed tomography. Notably, the LRR in the young donor group was significantly increased compared with that in the elderly donor group at 7 days postoperatively (P<0.05). Among recipients, TB in the elderly group was significantly increased compared with that in the young group at 1-5 days postoperatively (P<0.05). The residual liver regeneration rate was decreased and the time of jaundice was prolonged in recipients in the elderly group 7 days postoperatively, but donor age had little impact on the short-term outcome of the residual liver and graft.

The Role of Adipokines in Surgical Procedures Requiring Both Liver Regeneration and Vascular Occlusion

Liver regeneration is a perfectly calibrated mechanism crucial to increase mass recovery of small size grafts from living donor liver transplantation, as well as in other surgical procedures including hepatic resections and liver transplantation from cadaveric donors. Regeneration involves multiple events and pathways in which several adipokines contribute to their orchestration and drive hepatocytes to proliferate. In addition, ischemia-reperfusion injury is a critical factor in hepatic resection and liver transplantation associated with liver failure or graft dysfunction post-surgery. This review aims to summarize the existing knowledge in the role of adipokines in surgical procedures requiring both liver regeneration and vascular occlusion, which increases ischemia-reperfusion injury and regenerative failure. We expose and discuss results in small-for-size liver transplantation and hepatic resections from animal studies focused on the modulation of the main adipokines associated with liver diseases and/or regeneration published in the last five years and analyze future perspectives and their applicability as potential targets to decrease ischemia-reperfusion injury and improve regeneration highlighting marginal states such as steatosis. In our view, adipokines means a promising approach to translate to the bedside to improve the recovery of patients subjected to partial hepatectomy and to increase the availability of organs for transplantation.

Serial Assessment of Growth Factors Associated with Liver Regeneration in Patients Operated with Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy

BACKGROUND

There is limited knowledge about the mechanisms behind the unparalleled growth of the future liver remnant (FLR) linked to associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). In this study, liver regenerative markers were examined in patients subjected to ALPPS.

METHODS

Ten patients with colorectal liver metastases treated with neoadjuvant chemotherapy and ALPPS were included. Plasma was sampled at 6 time points and biopsies from both liver lobes were collected at both stages of ALPPS. The levels of interleukin (IL)-6, hepatocyte growth factor (HGF), tumor necrosis factor-α, epidermal growth factor, and vascular endothelial growth factor in plasma were measured at each time point. Expression of mRNA for markers of proliferation and apoptosis was studied in the biopsies from both liver lobes taken at both stages.

RESULTS

ALPPS resulted in a peak of IL-6 after stage 1 (p = 0.004), which decreased rapidly and did not increase again after stage 2. HGF also increased after stage 1 (p = 0.048), and the HGF levels correlated significantly with the degree of growth of the FLR before stage 2 (p = 0.02, r2 = 0.47). There was a correlation between peak levels of IL-6 and HGF (p = 0.03, r2 = 0.84).

CONCLUSIONS

IL-6 and HGF seem to be early mediators of hypertrophy after stage 1 in the ALPPS procedure. The peak HGF plasma level correlates with the degree of FLR growth in patients subjected to ALPPS.

Liver Regeneration in the Acute Liver Failure Patient

Liver regeneration after simple resection represents a unique process in which the organ returns to its original size and histologic structure. Over the past 30 years, there has been significant progress in elucidating the mechanisms associated with regeneration after loss of hepatic mass. Liver regeneration after acute liver failure shares several of these classical pathways. It differs, however, in key processes, including the role of both differentiated and stemlike cells. This article outlines these differences in addition to new molecular mechanisms, including immunomodulation, microRNAs, and the gut-liver axis. In addition, applications to the patient population, including prognostication and stem cell therapies, are explored.

Factors Affecting Liver Regeneration in Living Donors After Hepatectomy

Background

The safety of living liver donors is the paramount priority of liver transplantation surgeons. The liver has an effective regeneration capacity. The regeneration rate of the liver remnant in living liver donors provides much information useful in liver surgery. The outcome of the remnant liver after hepatectomy can be affected by many different perioperative factors.

Material/Methods

A total of 46 patients were enrolled in the study. Retrospective clinical data, including preoperative and postoperative early and late computed tomography liver volumetry measurements, estimated resection volumes, resected liver weights, and postoperative laboratory values, were statistically evaluated according to the liver resection type.

Results

No significant difference was detected in age, sex, calculated and computed tomography estimated total liver volume, intraoperative Hb decrease, postoperative complications, or postoperative portal vein flow rate. Postoperative liver enlargement rates were significant higher in the right hemihepatectomy (RHH) group than in the left lateral sectionectomy (LLS) group. The size of the liver remnant or graft has a major effect on regeneration rate. Postoperative biliary leakage did not have any significant effect on liver regeneration. No post-hepatectomy liver failure was detected among the liver donors.

Conclusions

Liver hypertrophy depends on the extent of liver resection. The cause of volume decrease in the LLS group after hepatectomy in our series appears to be the gradual atrophy of liver segment 4. RHH and LLS surgeries differ from each other in terms of resected liver volume, as well as inflammatory activity, and the latter appears to affect liver regeneration.

Influence of the colon in liver regeneration of rats submitted to hepatectomy and colectomy

OBJECTIVE

to evaluate whether colectomy, associated with 70% hepatectomy, influences liver regeneration in rats.

METHODS

we distributed 18 Wistar rats in three groups of six animals each. In group I (sham), we performed laparotomy; In group II, colectomy + 70% hepatectomy; In group III, only 70% hepatectomy. On the 6th postoperative day, we collected blood by cardiac puncture under anesthesia, followed by euthanasia. We performed serum dosages of aspartate aminotransferase (AST), alanine aminotransferase (ALT), albumin and alkaline phosphatase (AF), hepatocyte growth factor (HGF) and transforming growth factor-α (TGF-α). We calculated liver regeneration by the formula: liver weight ratio per 100g body weight at the time of euthanasia / liver weight preoperatively projected for 100g body weight × 100.

RESULTS

ALT and AST levels were significantly lower in group II when compared with group III (p<0.001). Albuminemia showed significantly higher levels in group II. Levels of HGF and TGF-α in group II were significantly higher than in group III. The percentage of hepatic regeneration was significantly higher in group II than in group III.

CONCLUSION

Colectomy performed simultaneously with 70% hepatectomy had a positive influence on liver regeneration in rats. Further research is needed to reveal the molecular mechanisms of this effect and to characterize the colon influence in liver physiology.

Serial changes of cytokines and growth factors in peripheral circulation after right lobe donor hepatectomy

Cytokines and growth factors have prominent roles in liver regeneration. The aim of this study was to evaluate the biological markers of liver regeneration in healthy donors undergoing right lobe donor hepatectomy for living donor liver transplantation. Twenty-five voluntary liver donors were enrolled. Peripheral blood samples were taken a day before the operation and on postoperative days (PODs) 1, 3, 7, 14, and 42. Levels of hepatocyte growth factor (HGF), interleukin (IL) 6, tumor necrosis factor α (TNF-α), thrombopoietin (TPO), transforming growth factor β1 (TGF-β1), interferon (IFN) α, and IFNγ were monitored. The remnant liver volume (RLV) before surgery and regeneration liver volume (RgV) on POD 14 were calculated on computed tomography (CT). RgV/RLV ratio was correlated with the remnant-liver-volume-to-body-weight ratio (RLVBWR). Inverse correlation was observed between RgV/RLV and RLVBWR (r(2) = 0.61; P < 0.001). There was a significant rise of HGF on POD 1 (P = 0.001), POD 7 (P = 0.049), and POD 14 (P = 0.04). TNF-α was elevated on POD 1 (P = 0.004). The levels of IL 6 (P < 0.001) and TPO (P < 0.001) were higher from POD 1 to POD 42. IFNα was higher on POD 14 (P = 0.003) and POD 42 (P = 0.001). There was a significant fall of IFNγ on POD 1 (P = 0.01) and increase on POD 14 (P = 0.04). The levels of TGF-β1 were higher on POD 14 (P = 0.008) and on POD 42 (P = 0.002). In conclusion, HGF, IL 6, TNF-α, and TPO are involved in the early phase, whereas TGF-β1 and IFN are involved in the termination phase of liver regeneration. Liver regeneration was observed to be higher in donors with low RLVBWR.

CSF1 Restores Innate Immunity After Liver Injury in Mice and Serum Levels Indicate Outcomes of Patients With Acute Liver Failure

BACKGROUND & AIMS

Liver regeneration requires functional liver macrophages, which provide an immune barrier that is compromised after liver injury. The numbers of liver macrophages are controlled by macrophage colony-stimulating factor (CSF1). We examined the prognostic significance of the serum level of CSF1 in patients with acute liver injury and studied its effects in mice.

METHODS

We measured levels of CSF1 in serum samples collected from 55 patients who underwent partial hepatectomy at the Royal Infirmary Edinburgh between December 2012 and October 2013, as well as from 78 patients with acetaminophen-induced acute liver failure admitted to the Royal Infirmary Edinburgh or the University of Kansas Medical Centre. We studied the effects of increased levels of CSF1 in uninjured mice that express wild-type CSF1 receptor or a constitutive or inducible CSF1-receptor reporter, as well as in chemokine receptor 2 (Ccr2)-/- mice; we performed fate-tracing experiments using bone marrow chimeras. We administered CSF1-Fc (fragment, crystallizable) to mice after partial hepatectomy and acetaminophen intoxication, and measured regenerative parameters and innate immunity by clearance of fluorescent microbeads and bacterial particles.

RESULTS

Serum levels of CSF1 increased in patients undergoing liver surgery in proportion to the extent of liver resected. In patients with acetaminophen-induced acute liver failure, a low serum level of CSF1 was associated with increased mortality. In mice, administration of CSF1-Fc promoted hepatic macrophage accumulation via proliferation of resident macrophages and recruitment of monocytes. CSF1-Fc also promoted transdifferentiation of infiltrating monocytes into cells with a hepatic macrophage phenotype. CSF1-Fc increased innate immunity in mice after partial hepatectomy or acetaminophen-induced injury, with resident hepatic macrophage as the main effector cells.

CONCLUSIONS

Serum CSF1 appears to be a prognostic marker for patients with acute liver injury. CSF1 might be developed as a therapeutic agent to restore innate immune function after liver injury.

Peritumoral Cbl is a strong independent prognostic marker after curative resection of hepatocellular carcinoma

Growing evidences support the concept that peritumoral microenvironment gene expression is an important element for physicians to make an accurate prognosis. Nonetheless, the correlation between peritumoral ubiquitin ligases and the hepatocellular carcinoma (HCC) survival remains unclear till this present. The expression of intratumoral and peritumoral Casitas B-lineage Lymphoma (Cbl) and epidermal growth factor receptor (EGFR) in hepatocellular carcinomas (HCCs) followed by curative resection was assessed by tissue microarray-based immune-histochemistry in two independent cohorts (n = 352). Their respective prognostic values and other clinicopathologic factors were then evaluated. The peritumoral Cbl density, much higher than that in intratumoral tissue, was an independent prognostic factor for overall survival (P < 0.001) and time to recurrence (P < 0.001) of HCCs after curative resection. The hazard ratio were 1.587 and 1.689, respectively. However, there was no correlation between intratumoral Cbl and prognosis. The peritumoral Cbl was also associated with prognosis even in HCC subgroups with small tumor size, negative AFP, without microvascular invasion and negative HBeAg. After a thorough analysis pertaining to the key role of Cbl on ubiquitination and degradation of activated receptor tyrosine kinases, we eventually discovered the negative correlation between peritumoral Cbl and EGFR (P = 0.015). Furthermore, the combination of peritumoral Cbl and EGFR serves as a much stronger indicator to make an accurate prognosis, especially during early recurrence (P < 0.001). These findings suggest that low expression of peritumoral Cbl and EGFR were positively associated with tumor size, microvascular invasion and patients survival after hepatectomy, highlighting the key role of peritumoral liver milieu in HCC progression.

Cigarette smoking increases risk of early morbidity after hepatic resection in patients with hepatocellular carcinoma

AIMS

Cigarette smoking is an important risk factor for the development of postoperative pulmonary complications after major surgical procedures. The objective of this study was to investigate whether preoperative smoking has any impact on early morbidity after liver resection for hepatocellular carcinoma (HCC).

METHODS

Data of 425 consecutive patients undergoing partial hepatectomy for HCC was retrospectively reviewed. Smoking and drinking habits, biochemical tests, tumor status, operation data, and any postoperative complications occurring before discharge from the hospital were documented. The risk factors promoting postoperative complications were analyzed by univariate and multivariate methods.

RESULTS

The overall morbidity rate was 40% (170 of 425). 166 patients were current smokers (39%). By multivariate analysis, liver cirrhosis (Risk Ratio (RR) 4.0, 95% confidence interval (CI) 2.0-8.0), smoking status (RR 3.0, 95% CI 1.7-5.1), PY of smoking (RR 1.3, 95% CI 1.1-1.9), preoperative platelet count (RR 1.6, 95% CI 1.4-2.0) and major hepatectomy (RR 1.4, 95% CI 1.1-1.8) were independent risk factors of postoperative morbidity (all p < 0.05). Liver failure, bile leakage, intractable ascites, chest and wound infection were more frequently occurred in smokers than non-smokers. Current smokers had higher postoperative morbidity than non- & former smokers in patients with normal liver and those with liver cirrhosis (p = 0.047 and p < 0.001, respectively).

CONCLUSIONS

Cigarette smoking is an independent risk factor for the development of liver-related and infectious complications in patients undergoing partial hepatectomy for HCC, especially in those with liver cirrhosis.