Molecular mechanisms of liver metastasis

N-glycosylation at N57/100/110 affects CD44s localization, function and stability in hepatocellular carcinoma

The glycosylation levels of proteins in cancer cells are closely related to cancer invasion and migration. CD44 is a transmembrane glycoprotein that is significantly overexpressed in a variety of tumor cells and has been proven to promote the migration and motility of cancer cells, but the effect of its N-glycosylation modification on CD44 protein function in tumors is less studied. Here, we investigated the effect of six N-glycan chains (N25/57/100/110/120/255) on CD44s localization, function and stability in hepatocarcinoma cells. When the six sites were mutated, we found that CD44s lost its membrane localization in Huh7 and MHCC-97H cells. On this basis, we identified three glycosylation sites on CD44s (N57, N100 and N110) that played key roles in intracellular localization. When N57, N100 and N110 were mutated together, CD44 localized to the cytoplasm, while another three-site mutant (N25/N120/N255) was still anchored to the membrane. In addition, the ability of CD44-N57Q/N100Q/N110Q to promote the metastasis and invasion of Huh7 and 97H cells was weakened compared with that of CD44-N25Q/N120Q/N255Q. Furthermore, CD44-N57Q/N100Q/N110Q accumulated abnormally in the ER, and a high level of the ER stress (ERS) marker BiP was detected at the same time compared with wild-type CD44. When the lysosome inhibitor CQ was added, the content of mutant protein that triggered ERS significantly increased, which indicated that the degradation mode of CD44-N57Q/N100Q/N110Q after ERS was mainly through the lysosomal pathway (ERLAD). The results revealed that the N-glycosylation sites N57, N100 and N110 mutated on CD44s affected its function and degraded it by lysosomes after triggering ERS. These findings provide data for new studies on ER-related degradation, further promote the study of the glycan chain function of CD44 and furnish new ideas for the treatment of liver cancer metastasis.

Molecular Mechanisms of Colorectal Liver Metastases

The liver is the most frequently target for metastasis among patients with colorectal cancer mainly because of the portal vein circulation that directly connects the colon and rectum with the liver. The liver tumor microenvironment consists of different cell types each with unique characteristics and functions that modulate the antigen recognition and immune system activation. Primary tumors from other sites "prime" the liver prior to the seeding of cancer cells, creating a pre-metastatic niche. Following invasion into the liver, four different phases are key to the development of liver metastases: a microvascular phase in which cancer cells infiltrate and become trapped in sinusoidal vessels; an extravascular, pre-angiogenic phase; an angiogenic phase that supplies oxygen and nutrients to cancer cells; and a growth phase in which metastatic cells multiply and enlarge to form detectable tumors. Exosomes carry proteins, lipids, as well as genetic information that can create a pre-metastatic niche in distant sites, including the liver. The complexity of angiogenic mechanisms and the exploitation of the vasculature in situ by cancer cells have limited the efficacy of currently available anti-angiogenic therapies. Delineating the molecular mechanisms implicated in colorectal liver metastases is crucial to understand and predict tumor progression; the development of distant metastases; and resistance to chemotherapy, immunotherapy, and targeted treatment.

Synchronous liver and peritoneal metastases from colorectal cancer: Is cytoreductive surgery and hyperthermic intraperitoneal chemotherapy combined with liver resection a feasible option?

BACKGROUND

Traditionally, synchronous liver resection (LR), cytoreductive surgery (CRS), and hyperthermic intraperitoneal chemotherapy for colorectal liver and peritoneal metastases have been contraindicated. Nowadays, clinical practice has promoted this aggressive treatment in selected cases. This study aimed to review surgical and survival results of an extensive surgical approach including CRS with hyperthermic intraperitoneal chemotherapy (HIPEC) and LR.

METHODS

PubMed, EMBASE, and Web of Science databases were matched to find the available literature on this topic. The search period was limited to 10 years (January 2010-January 2021). A threshold of case series of 10 patients or more was applied.

RESULTS

In the search period, out of 114 studies found about liver and peritoneal metastases from colorectal cancer, we found 18 papers matching the inclusion criteria. Higher morbidity and mortality were reported for patients who underwent such an extensive surgical approach when compared with patients who underwent only cytoreductive surgery and HIPEC. Also, survival rates seem worse in the former than in the latter.

CONCLUSION

The role of combined surgical strategy in patients with synchronous liver and peritoneal metastases from colorectal cancer remains controversial. Survival rates and morbidity and mortality seem not in favor of this option. A more accurate selection of patients and more restrictive surgical indications could perhaps help improve results in this subgroup of patients with limited curative options.

GALNT2 promotes invasiveness of colorectal cancer cells partly through AXL

GalNAc-type O-glycosylation and its initiating GalNAc transferases (GALNTs) play crucial roles in a wide range of cellular behaviors. Among 20 GALNT members, GALNT2 is consistently associated with poor survival of patients with colorectal cancer in public databases. However, its clinicopathological significance in colorectal cancer remains unclear. In this study, immunohistochemistry showed that GALNT2 was overexpressed in colorectal tumors compared with the adjacent nontumor tissues. GALNT2 overexpression was associated with poor survival of colorectal cancer patients. Forced expression of GALNT2 promoted migration and invasion as well as peritoneal metastasis of colorectal cancer cells. In contrast, GALNT2 knockdown with siRNAs or knockout with CRISPR/Cas9 system suppressed these malignant properties. Interestingly, we found that GALNT2 modified O-glycans on AXL and determined AXL levels via the proteasome-dependent pathway. In addition, the GALNT2-promoted invasiveness was significantly reversed by AXL siRNAs. These findings suggest that GALNT2 promotes colorectal cancer invasion at least partly through AXL.

Proteome biology of primary colorectal carcinoma and corresponding liver metastases

Colorectal adenocarcinomas (CRC) are one of the most commonly diagnosed tumors worldwide. Colorectal adenocarcinomas primarily metastasize into the liver and (less often) into the peritoneum. Patients suffering from CRC-liver metastasis (CRC-LM) typically present with a dismal overall survival compared to non-metastasized CRC patients. The metastasis process and metastasis-promoting factors in patients with CRC are under intensive debate. However, CRC studies investigating the proteome biology are lacking. Formalin-fixed paraffin-embedded (FFPE) tissue specimens provide a valuable resource for comprehensive proteomic studies of a broad variety of clinical malignancies. The presented pilot study compares the proteome of primary CRC and patient-matched CRC-LM. The applied protocol allows a reproducible and straightforward identification and quantification of over 2,600 proteins within the dissected tumorous tissue. Subsequent unsupervised clustering reveals distinct proteome biologies of the primary CRC and the corresponding CRC-LM. Statistical analysis yields multiple differentially abundant proteins in either primary CRC or their corresponding liver metastases. A more detailed analysis of dysregulated biological processes suggests an active immune response in the liver metastases, including several proteins of the complement system. Proteins with structural roles, e.g. cytoskeleton organization or cell junction assembly appear to be less prominent in liver metastases as compared to primary CRC. Immunohistochemistry corroborates proteomic high expression levels of metabolic proteins in CRC-LM. We further assessed how the in vitro inhibition of two in CRC-LM enriched metabolic proteins affected cell proliferation and chemosensitivity. The presented proteomic investigation in a small clinical cohort promotes a more comprehensive understanding of the distinct proteome biology of primary CRC and their corresponding liver metastases.

Tumor Microenvironment in Metastatic Colorectal Cancer: The Arbitrator in Patients' Outcome

Simple Summary

Colorectal cancer accounts for approximately 10% of all annually diagnosed cancers worldwide being liver metastasis, the most common cause of death in patients with colorectal cancer. The interplay between tumor and stromal cells in the primary tumor microenvironment and at distant metastases are rising in importance as potential mechanisms of the tumor progression. In this review we discuss the new biomarkers derived from tumor microenvironment and liquid biopsy as emerging prognostic and treatments response markers for metastatic colorectal cancer. We also review the developing new clinical strategies based on tumor microenvironmental cells to tackle metastatic disease in metastatic colorectal cancer patients.

Abstract

Colorectal cancer (CRC) is one of the most common cancers in western countries. Its mortality rate varies greatly, depending on the stage of the disease. The main cause of CRC mortality is metastasis, which most commonly affects the liver. The role of tumor microenvironment in tumor initiation, progression and metastasis development has been widely studied. In this review we summarize the role of the tumor microenvironment in the liver pre-metastatic niche formation, paying attention to the distant cellular crosstalk mediated by exosomes. Moreover, and based on the prognostic and predictive capacity of alterations in the stromal compartment of tumors, we describe the role of tumor microenvironment cells and related liquid biopsy biomarkers in the delivery of precise medication for metastatic CRC. Finally, we evaluate the different clinical strategies to prevent and treat liver metastatic disease, based on the targeting of the tumor microenvironment. Specifically, targeting angiogenesis pathways and regulating immune response are two important research pipelines that are being widely developed and promise great benefits.

Diagnostic accuracy of serum endothelin-1 in patients with HCC on top of liver cirrhosis

Background

Hepatocellular carcinoma (HCC) is one of the most common cancers and one of the main causes of cancer-related deaths. As the overall survival of patients with cirrhosis has improved and the global incidence of HCC has continued to increase, strategies for the early detection of HCC are urgently needed for better prognosis. In this study, we aimed to assess the accuracy of endothelin-1 in the diagnosis of HCC in cirrhotic patients in comparison with alpha-fetoprotein (AFP) and whether it could predict its vascular spread. This is a case–control study that included 70 cirrhotic patients with or without hepatocellular carcinoma. Patients were subjected to complete medical history taking, clinical examination and laboratory investigations including serum endothelin-1, alpha-fetoprotein, abdominal ultrasound and Triphasic multi-slice computed tomography (CT; abdomen and pelvis). The outcome results obtained for endothelin-1 were used to assess its diagnostic accuracy in HCC diagnosis and the prediction of presence of vascular spread.

Results

There was a statistically significant increase in serum endothelin-1 in HCC in comparison to cirrhotic patients and normal persons (P value < 0.001). Sensitivity, specificity, and positive and negative predictive values at cut-off point of 5.2 pg/ml for HCC were 90%, 100%, 100%, and 90.9% respectively. There was no statistically significant association between serum endothelin-1 level and portal vein thrombosis in HCC (P value = 0.547).

Conclusion

Endothelin-1 has high sensitivity and specificity for diagnosis of hepatocellular carcinoma. However, it has little value for prediction of its vascular spread.

The Role Of Hepatic Stellate Cells In Promoting Liver Metastasis Of Colorectal Carcinoma

Purpose

Colorectal cancer (CRC) is the most common malignancy in the gastrointestinal tract. The liver is the most common location of CRC metastases, which are the main causes of CRC-related death. However, the mechanisms underlying metastasis of CRC to the liver have not been characterized, resulting in therapeutic challenges.

Methods

The effects of hepatic stellate cells (HSCs) on T cells were evaluated using in vitro mixed lymphocyte reactions (MLRs) and cytokine production assays. HSC-induced CT26 cell migration and proliferation were evaluated in vitro and in vivo.

Results

HSCs induced T cell hypo-responsiveness, promoted T cell apoptosis, and induced regulatory T cell expansion in vitro. IL-2 and IL-4 were significantly lower in MLRs incubated with HSCs. Supernatants of MLRs with HSCs promoted CT26 cell proliferation and migration. Furthermore, the presence of HSCs increased the number of liver metastases and promoted proliferation of liver metastatic tumor cells in vivo.

Conclusion

HSCs may contribute to an immunosuppressive liver microenvironment, resulting in a favorable environment for the colonization of CRC cells in the liver. These findings highlight a potential strategy for treatment of CRC liver metastases.

Liver Metastases and Histological Growth Patterns: Biological Behavior and Potential Clinical Implications-Another Path to Individualized Medicine?

Colorectal cancer is a major health burden and despite the recent advances in healthcare and screening programs, a great percentage of patients already present metastases once their disease is found. In those cases, liver surgery has an essential role, but even with neoadjuvant chemotherapy there is a high rate of intrahepatic recurrence. New prognostic factors are needed in order to decide the best surgical approach considering the biological behavior of the tumors in order to tailor the used therapies, moving towards individualized medicine/treatment. However, the majority of the factors described in literature are expensive, time consuming, and difficult to apply on a daily basis. Histological growth patterns have emerged over the past few years as a reproducible characteristic, an easy to apply one, and with very low costs since it only needs the standard Haematoxylin and Eosin stained slides of observation. In this article, we provide a review of the histological growth patterns of liver metastases and their prognostic significance, biological meaning, and therapeutic importance.

Impact of Synchronous Liver Resection on the Perioperative Outcomes of Patients Undergoing CRS-HIPEC

BACKGROUND

While liver resection (LR) and cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) are commonly performed for hepatic and peritoneal metastases, respectively, the safety of synchronous LR and CRS-HIPEC has not been established.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) databases from 2005 to 2016 were used to identify patients who underwent CRS-HIPEC. Demographic, clinical, and perioperative outcomes were compared among patients who underwent CRS-HIPEC with and without synchronous LR.

RESULTS

Among 1168 patients who underwent CRS-HIPEC, 100 (8.6%) underwent synchronous LR and 1068 (91.4%) did not. The most common primary diagnosis was unspecified (65.3%) followed by appendix (16.0%) and colorectal (12.5%). Among patients who underwent CRS-HIPEC plus LR, the majority had a partial hepatectomy (96.0%), while a small subset underwent trisegmentectomy (2.0%) or hemihepatectomy (2.0%). Patients who underwent CRS-HIPEC plus LR underwent a greater number of operative procedures (8.3 ± 2.5 vs 6.7 ± 2.5, p < 0.001), had a longer operative time (520.7 ± 155.3 vs 454.6 ± 160.7 min, p = 0.001), had a longer hospital length of stay (16.7 ± 15.6 vs 11.1 ± 11.5 days, p < 0.001), were more likely to require reoperation (13.0 vs 6.9%, p = 0.03), and experienced greater 30-day morbidity (47.0 vs 27.4%, p < 0.001), but not mortality (3.0 vs 1.4%, p = 0.22). On multivariate logistic regression, LR was strongly associated with increased risk of postoperative morbidity even after controlling for potential confounders (OR 1.65, 95% CI 1.03-2.64).

CONCLUSIONS

Simultaneous LR and CRS-HIPEC was associated with increased operative time, length of hospital stay, reoperation, and postoperative morbidity compared to CRS-HIPEC alone. For patients with synchronous hepatic and peritoneal metastases, a staged operative approach should be considered.

Tunicamycin inhibits cell proliferation and migration in hepatocellular carcinoma through suppression of CD44s and the ERK1/2 pathway

Tunicamycin (TM) is an N‐linked glycosylation (NLG) inhibitor with strong antitumor activity, the exact underlying molecular mechanism of which remains to be elucidated. In our previous studies, we found that TM reversed drug resistance and improved the efficacy of combination treatments for hepatocellular carcinomas (HCC). Here, we investigated the effects of TM on HCC cell proliferation and migration as well as the mechanism of those effects. Our results showed that TM inhibited cell proliferation and migration as well as induced apoptosis of hepatocellular carcinoma cells. TM inhibited proliferation of HCC cells by inducing cell apoptosis and cell cycle arrest at the G2/M phase. Meanwhile, TM inhibited migration of HCC cells by suppressing CD44s‐mediated epithelial‐mesenchymal transition (EMT). TM inhibited migration and invasion of HCC cells by decreasing CD44 expression and altering its glycosylation. In addition, CD44s is involved in promoting EMT and is associated with a poor prognosis in HCC patients. Overexpression of CD44s promoted tumor migration and activated phosphorylation of ERK1/2 in HCC cells, whereas TM inhibited CD44s overexpression‐associated cell migration. The ability of TM to inhibit cell migration and invasion was enhanced or reversed in CD44s knockdown cells and cells overexpressing CD44s, respectively. The MEK/ERK inhibitor U0126 and TM inhibited hyaluronic acid‐induced cell migration in HCC cells. Furthermore, TM inhibited exogenous transforming growth factor beta (TGF‐β)‐mediated EMT by an ERK1/2‐dependent mechanism and restored the TGF‐β‐mediated loss of E‐cadherin. In summary, our study provides evidence that TM inhibits proliferation and migration of HCC cells through inhibition of CD44s and the ERK1/2 signaling pathway.

Serum CA19-9 as a marker of circulating tumor cells in first reflux blood of colorectal cancer patients

Circulating tumor cells (CTCs) are used for metastasis surveillance in cancer patients, but low detection rates limit their use in colorectal cancer (CRC). We investigated the distribution of CTCs in peripheral and portal blood of CRC patients, and analyzed the relationship between serum tumor CEA/CA19-9 markers and CTCs blood levels. CTC levels detected in first reflux/portal vein blood were higher than in peripheral blood, and liver reduced CTCs amount. CTCs-positive patients had increased serum CEA and CA 19-9 levels, and the CEA and CA 19-9 levels correlated with the CTCs levels. Even in non-metastatic CRC patients with barely detectable CTCs in peripheral blood, serum CA 19-9 levels correlated with the CTC levels in first reflux/portal vein blood. These results demonstrate that CTC detection in the first reflux vein/portal vein blood is more sensitive than in peripheral blood, suggesting that clinical diagnosis using the CellSearch System should be based on the CTC detection in first reflux vein blood due to the high detection rates. In addition, our results indicate that serum CA 19-9 levels may serve as a diagnostic marker for further evaluation of CTC levels in portal blood.

Biology and therapeutic implications of VEGF-A splice isoforms and single-nucleotide polymorphisms in colorectal cancer

Tumor growth, dissemination and metastasis are dependent on angiogenesis. The predominant vascular endothelial growth factor (VEGF) isoform that plays a major role in angiogenesis is VEGF-A. Indeed, VEGF-A is implicated in promoting angiogenesis of numerous solid malignancies, including colorectal cancer (CRC). A large body of preclinical and clinical evidence indicates that the expression of specific VEGF-A isoforms represents a predominant pro-angiogenic factor, which is associated with formation of metastases and poor prognosis in CRC patients. Different isoforms of human VEGF-A have been identified, all of which arise from alternative splicing of the primary transcript of a single gene. Notably, it has been recently demonstrated that expression of type 3 isoform pattern is significantly correlated with venous involvement in CRC as well as in progression to metastatic colorectal cancer (mCRC), although it remains unclear what proportion of CRC tumors express these isoforms. This review highlights the importance of investigating the genetic and the epigenetic variations in VEGF-A pathways in CRC, the functions of different VEGF-A isoforms and their potential application as prognostic markers and/or therapeutic targets. Better understanding of the mechanisms controlling angiogenesis in liver metastases is necessary to address the limitations of current anti-angiogenic therapies.

Extracellular HSP70/HSP70-PCs regulate hepatocarcinoma cell migration and invasion via RhoA

The effects of heat shock protein 70 (HSP70)/HSP70-peptide complexes (HSP70-PCs) on the invasion and metastasis ability of hepatocellular carcinoma (HCC) Huh-7 cells were investigated. Wound healing assay revealed that cells treated with HSP70/HSP70-PCs healed faster than negative control cells. HSP70/HSP70-PCs-treated cells also exhibited better migration ability and higher invasion ability than control cells. HSP70/HSP70-PCs treatment did not alter the messenger RNA (mRNA) or protein levels of matrix metalloproteinase-9; the opposite was true for Ras homolog family member A (RhoA) mRNA and protein levels. RNA interference of RhoA attenuated the migration of HSP70/HSP70-PCs-treated cells. The present findings indicate that regulation of HCC cell migration by HSP70/HSP70-PCs occurs via regulation of RhoA expression.

CXCL10/CXCR3 overexpression as a biomarker of poor prognosis in patients with stage II colorectal cancer

The CXCL10/CXCR3 axis of inflammatory mediators is one of the most important groups of chemokine axes, which has been proven to be a lymphocyte-associated metastasis mediator in several tumors. The term inflammatory adhesions refers to tumors found to be attached to the surrouding tissues during surgery, although no cancer cell infiltration is later identified on pathological examination. The aim of the present study was to investigate the clinical characteristics of stage II colorectal cancer (CRC) and determine the correlation between the CXCL10/CXCR3 axis, inflammatory adhesions and prognosis. Clinicohistopathological data were collected from 401 CRC patients who had undergone R0 resection. Statistical analysis was performed with SPSS 17.0 software. Immunohistochemistry (IHC) was applied to measure the expression of CXCL10 and CXCR3 in 71 recurrent CRC patients, 72 non-recurrent CRC patients and 10 samples from normal peritumoral tissues, all retrieved from the Tianjin Medical University Cancer Institute and Hospital, Tianjin, China. Inflammatory adhesions, tumor location and size and the number of high-risk factors for reccurrence were more significantly associated with overall survival (OS) rather than disease-free survival in all the patients as determined by the log-rank and Cox's regression hazard analysis. Further analysis demonstrated that only the presence of inflammatory adhesions (P=0.025) was associated with the OS of recurrent patients. Patients with recurrence exhibited higher CXCR3 (P<0.001) and CXCL10 (P<0.001) expression compared with non-recurrent patients, as determined by IHC. The correlation between clinicopathological variables, CXCL10/CXCR3 expression and survival was also analyzed: Inflammatory adhesions and general tumor type (ulcerated vs. elevated) exhibited a significant correlation with CXCR3; however, the expression of CXCL10 was not significantly correlated with tumor location, histological type, size, gender, or preoperative carcinoembryonic antigen and hemoglobin levels. Furthermore, patients exhibiting a high expression of CXCR3 presented with a higher risk of relapse; among those, patients with inflammatory adhesions always exhibited worse survival. However, no such association was identified for CXCL10 expression. In conclusion, CXCR3 expression may be used as a prognostic marker and may contribute to the prediction of clinical outcome in stage II CRC patients.

Activation of ETA Receptor by Endothelin-1 Induces Hepatocellular Carcinoma Cell Migration and Invasion via ERK1/2 and AKT Signaling Pathways

Endothelin-1 (ET-1), a member of endothelins family, binds to ETA receptor (ETAR) and ETB receptor to exert its role in multiple cellular processes. Although ET-1 and its receptors has been reported to be overexpressed in many cancers, and overexpression of ET-1 is able to trigger hepatocarcinogenesis in zebrafish, the functions of ET-1 and its receptors in hepatocellular carcinoma (HCC) cell migration and invasion remain unclear. In the present study, we found that ETAR was greatly expressed in HCC cells and HCC tissues. ETAR expression as well as ET-1 expression was associated with vascular invasion and tumor stage in HCC. Activation of ETAR by ET-1 dose-dependently promoted cell migration and invasion of HCC cells, while silencing of ETAR by siRNA or blocking of ETAR by specific inhibitor resulted in significant reduction in ET-1-mediated migration and invasion. Furthermore, ET-1 induced activation of ERK1/2 and AKT and increased MMP-3 production via ETAR. In addition, using inhibitors of ERK1/2 and AKT, we found that ERK1/2 and AKT pathways were both involved in ETAR-mediated migration, invasion, and MMP-3 production. Taken together, our findings suggest that activation of ETAR by ET-1 promotes HCC cell migration and invasion via activating ERK1/2 and AKT signaling pathways and upregulating MMP-3 expression. Thus, ETAR may play an important role in the progress of HCC.

Impact of proteolytic enzymes in colorectal cancer development and progression

Tumor invasion and metastasis is a highly complicated, multi-step phenomenon. In the complex event of tumor progression, tumor cells interact with basement membrane and extracellular matrix components. Proteolytic enzymes (proteinases) are involved in the degradation of extracellular matrix, but also in cancer invasion and metastasis. The four categories of proteinases (cysteine-, serine-, aspartic-, and metalloproteinases) are named and classified according to the essential catalytic component in their active site. We and others have shown that proteolytic enzymes play a major role not only in colorectal cancer (CRC) invasion and metastasis, but also in malignant transformation of precancerous lesions into cancer. Tissue and serum-plasma antigen concentrations of proteinases might be of great value in identifying patients with poor prognosis in CRC. Our results, in concordance with others indicate the potential tumor marker impact of proteinases for the early diagnosis of CRC. In addition, proteinases may also serve as potential target molecules for therapeutic agents.

Patterns of recurrence after liver transplantation for nonresectable liver metastases from colorectal cancer

Background

Surgical resection is the only curative modality for colorectal liver metastases (CLM), and the pattern of recurrences after resection affects survival. In a prospective study of liver transplantation (Lt) for nonresectable CLM we have shown a 5-year overall survival rate of 60 %, but 19 of 21 experienced recurrence. This study reports the pattern of recurrences after Lt for CLM and the effect on survival.

Methods

Characterization of metastatic lesions in a prospective study for Lt for nonresectable CLM was performed (n = 21). The study included reexamination of chest computed tomographic scans taken before Lt.

Results

At the time of first recurrence, 16 were a single site, and three were multiple sites. Thirteen of the single sites were pulmonary recurrences. The pulmonary recurrences appeared early and were slow growing, and several were accessible to surgical treatment. When chest computed tomographic scans were reexamined, seven patients had pulmonary nodules at the time of Lt without an effect on survival. There was no first single-site hepatic recurrence. Six of the seven patients who developed metastases to the transplanted liver died from metastatic disease.

Conclusions

The pulmonary recurrences after Lt for CLM were of an indolent character, even those that were present at the time of Lt. This contrasts with the finding of metastases to the transplanted liver, which was prognostically adverse. The lack of single hepatic first-site recurrences and hepatic metastases only as part of disseminated disease is different from the pattern of recurrence after liver resection. This suggests two distinct mechanisms for hepatic recurrences after resection for CLM.

GRK6 expression in patients with hepatocellular carcinoma

OBJECTIVE

To investigate the expression and potential roles of G protein-coupled receptor kinase 6 (GRK6) in hepatocellular carcinoma (HCC) patients.

METHODS

Immunohistochemistry and Western blot was performed to determine GRK6 expression in 73 HCC samples. And the correlation with clinicopathological features was also analyzed.

RESULTS

GRK6 expression was significantly higher in HCC than that in normal hepatic tissue. GRK6 was positively correlated with proliferation marker Ki-67, clinical stage, metastasis and survival time.

CONCLUSIONS

Our results suggested that GRK6 overexpression plays an important role in HCC. Monitoring the expression of GRK6 maybe helpful in early diagnosis and prognosis of HCC.

The multifaceted role of the microenvironment in liver metastasis: biology and clinical implications

The liver is host to many metastatic cancers, particularly colorectal cancer, for which the last 2 decades have seen major advances in diagnosis and treatment. The liver is a vital organ, and the extent of its involvement with metastatic disease is a major determinant of survival. Metastatic cells arriving in the liver via the bloodstream encounter the microenvironment of the hepatic sinusoid. The interactions of the tumor cells with hepatic sinusoidal and extrasinusoidal cells (endothelial, Kupffer, stellate, and inflammatory cells) determine their fate. The sinusoidal cells can have a dual role, sometimes fatal to the tumor cells but also facilitatory to their survival and growth. Adhesion molecules participate in these interactions and may affect their outcome. Bone marrow-derived cells and chemokines also play a part in the early battle for survival of the metastases. Once the tumor cells have arrested and survived the initial onslaught, tumors can grow within the liver in 3 distinct patterns, reflecting differing host responses, mechanisms of vascularization, and proteolytic activity. This review aims to present current knowledge of the interactions between the host liver cells and the invading metastases that has implications for the clinical course of the disease and the response to treatment.