Reduced expression of low-density lipoprotein receptor in hepatocellular carcinoma with paraneoplastic hypercholesterolemia

Risk of cardiovascular death in patients with hepatocellular carcinoma based on the Fine-Gray model

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most common types of cancers worldwide, ranking fifth among men and seventh among women, resulting in more than 7 million deaths annually. With the development of medical technology, the 5-year survival rate of HCC patients can be increased to 70%. However, HCC patients are often at increased risk of cardiovascular disease (CVD) death due to exposure to potentially cardiotoxic treatments compared with non-HCC patients. Moreover, CVD and cancer have become major disease burdens worldwide. Thus, further research is needed to lessen the risk of CVD death in HCC patient survivors.

AIM

To determine the independent risk factors for CVD death in HCC patients and predict cardiovascular mortality (CVM) in HCC patients.

METHODS

This study was conducted on the basis of the Surveillance, Epidemiology, and End Results database and included HCC patients with a diagnosis period from 2010 to 2015. The independent risk factors were identified using the Fine-Gray model. A nomograph was constructed to predict the CVM in HCC patients. The nomograph performance was measured using Harrell's concordance index (C-index), calibration curve, receiver operating characteristic (ROC) curve, and area under the ROC curve (AUC) value. Moreover, the net benefit was estimated via decision curve analysis (DCA).

RESULTS

The study included 21545 HCC patients, of whom 619 died of CVD. Age (< 60) [1.981 (1.573-2.496), P < 0.001], marital status (married) [unmarried: 1.370 (1.076-1.745), P = 0.011], alpha fetoprotein (normal) [0.778 (0.640-0.946), P = 0.012], tumor size (≤ 2 cm) [(2, 5] cm: 1.420 (1.060-1.903), P = 0.019; > 5 cm: 2.090 (1.543-2.830), P < 0.001], surgery (no) [0.376 (0.297-0.476), P < 0.001], and chemotherapy(none/unknown) [0.578 (0.472-0.709), P < 0.001] were independent risk factors for CVD death in HCC patients. The discrimination and calibration of the nomograph were better. The C-index values for the training and validation sets were 0.736 and 0.665, respectively. The AUC values of the ROC curves at 2, 4, and 6 years were 0.702, 0.725, 0.740 in the training set and 0.697, 0.710, 0.744 in the validation set, respectively. The calibration curves showed that the predicted probabilities of the CVM prediction model in the training set vs the validation set were largely consistent with the actual probabilities. DCA demonstrated that the prediction model has a high net benefit.

CONCLUSION

Risk factors for CVD death in HCC patients were investigated for the first time. The nomograph served as an important reference tool for relevant clinical management decisions.

The evolving landscape of PCSK9 inhibition in cancer

Cancer is a disease with a significant global burden in terms of premature mortality, loss of productivity, healthcare expenditures, and impact on mental health. Recent decades have seen numerous advances in cancer research and treatment options. Recently, a new role of cholesterol-lowering PCSK9 inhibitor therapy has come to light in the context of cancer. PCSK9 is an enzyme that induces the degradation of low-density lipoprotein receptors (LDLRs), which are responsible for clearing cholesterol from the serum. Thus, PCSK9 inhibition is currently used to treat hypercholesterolemia, as it can upregulate LDLRs and enable cholesterol reduction through these receptors. The cholesterol-lowering effects of PCSK9 inhibitors have been suggested as a potential mechanism to combat cancer, as cancer cells have been found to increasingly rely on cholesterol for their growth needs. Additionally, PCSK9 inhibition has demonstrated the potential to induce cancer cell apoptosis through several pathways, increase the efficacy of a class of existing anticancer therapies, and boost the host immune response to cancer. A role in managing cancer- or cancer treatment-related development of dyslipidemia and life-threatening sepsis has also been suggested. This review examines the current evidence regarding the effects of PCSK9 inhibition in the context of different cancers and cancer-associated complications.

Paraneoplastic syndrome frequency and prognostic effect in hepatocellular carcinoma patients

OBJECTIVE

Symptomatic hepatocellular carcinoma (HCC) patients may generally display constitutional symptoms such as abdominal pain, weight loss, anorexia and localized mass, or atypical clinical features of paraneoplastic syndrome (PNS) such as hypercholesterolemia, hypercalcemia, hypoglycemia, erythrocytosis and thrombocytosis. The most common PNS in HCC is hypercholesterolemia, hypercalcemia, hypoglycemia and erythrocytosis. The aim of this study isto evaluate the relationship of PNS in HCC patients.

MATERIAL AND METHOD

In this study, the data of 534 patients who were followed up with the diagnosis of HCC between January 2010 and December 2020 in the Gastroenterology clinic were evaluated retrospectively. Clinical data, age, gender, complete blood count of patients with and without PNS, liver biochemistry, alpha-fetoprotein (AFP) level, hepatitis B surface antigen, anti-hepatitis B virus, Child-Pugh score, model for end-stage liver disease score, tumor volume, portal vein thrombosis, liver biopsy histology and radiologic images were taken from the hospital data system and analyzed.

RESULTS

Out of the 534 HCC patients, 120 (22.3%) were PNS-positive patients. There was a significant difference between the ages of PNS-positive and PNS-negative patients, and PNS-positive patients were older (64.60±12.97) (P=0.02). PNS-positive HCC was determined as hypoglycemia 5.8%, hypercalcemia 6.3%, erythrocytosis 3.9%, hypercholesterolemia 2.4% and thrombocytosis 3.9%. AFP level (22908 ± 60 ng/ml) and tumor diameter (>10 cm) were higher in the PNS-positive group. Multivariate analysis showed that stage C according to Child-Pugh score and tumor diameter >10 cm were independent predictors of poor prognosis, whereas PNS erythrocytosis and thrombocytosis were independent predictors of better prognosis.

CONCLUSION

In PNS-positive HCC patients, hypoglycemia and hypercalcemia were associated with poor prognosis according to Child-Pugh score, whereas erythrocytosis and thrombocytosis were associated with good prognosis.

Paraneoplastic syndromes in hepatocellular carcinoma: a review

INTRODUCTION

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and a significant proportion (20-40%) of patients with HCC develop paraneoplastic syndromes (PNS). Despite this, there is a paucity of clinical evidence regarding PNS in HCC.

AREAS COVERED

A systematic search was performed to identify relevant case studies regarding PNS in HCC. Another search was conducted to identify studies that evaluated the impact of PNS on survival outcomes in HCC. Since there are currently no international guidelines for PNS in HCC, this review aims to provide comprehensive summaries and recommendations of PNS in HCC, including the pathophysiology, clinical features, diagnostic approach, and management, so that clinicians remain guided in caring for HCC patients with PNS. In general, PNS are associated with poorer survival outcomes and negative prognostic markers of HCC.

EXPERT OPINION

The presence of PNS has a significant influence on survival rates and clinical outcomes of patients with HCC. They contribute to significant morbidity, influencing patients' quality of life and fitness for curative and palliative therapies. Therefore, it is paramount for PNS to be integrated into routine investigations after diagnosing HCC to guide further management and prognostication of the disease.

PCSK9 and cancer: Rethinking the link

BACKGROUND

Cancer is emerging as a major problem globally, as it accounts for the second cause of death despite medical advances. According to epidemiological and basic studies, cholesterol is involved in cancer progression and there are abnormalities in cholesterol metabolism of cancer cells including prostate, breast, and colorectal carcinomas. However, the importance of cholesterol in carcinogenesis and thereby the role of cholesterol homeostasis as a therapeutic target is still a debated area in cancer therapy. Proprotein convertase subtilisin/kexin type-9 (PCSK9), a serine protease, modulates cholesterol metabolism by attachment to the LDL receptor (LDLR) and reducing its recycling by targeting the receptor for lysosomal destruction. Published research has shown that PCSK9 is also involved in degradation of other LDLR family members namely very-low-density-lipoprotein receptor (VLDLR), lipoprotein receptor-related protein 1 (LRP-1), and apolipoprotein E receptor 2 (ApoER2). As a result, this protein represents an interesting therapeutic target for the treatment of hypercholesterolemia. Interestingly, clinical trials on PCSK9-specific monoclonal antibodies have reported promising results with high efficacy in lowering LDL-C and in turn reducing cardiovascular complications. It is important to note that PCSK9 mediates several other pathways apart from its role in lipid homeostasis, including antiviral activity, hepatic regeneration, neuronal apoptosis, and modulation of various signaling pathways. Furthermore, recent literature has illustrated that PCSK9 is closely associated with incidence and progression of several cancers. In a number of studies, PCSK9 siRNA was shown to effectively suppress the proliferation and invasion of the several studied tumor cells. Hence, a novel application of PCSK9 inhibitors/silencers in cancer/metastasis could be considered. However, due to poor data on effectiveness and safety of PCSK9 inhibitors in cancer, the impact of PCSK9 inhibition in these pathological conditions is still unknown.

SEARCH METHODS

A vast literature search was conducted to find intended studies from 1956 up to 2020, and inclusion criteria were original peer-reviewed publications.

PURPOSE OF REVIEW

To date, PCSK9 has been scantly investigated in cancer. The question that needs to be discussed is "How does PCSK9 act in cancer pathophysiology and what are the risks or benefits associated to its inhibition?". We reviewed the available publications highlighting the contribution of this proprotein convertase in pathways related to cancer, with focus on the potential implications of its long-term pharmacological inhibition in cancer therapy.

Metabolic factors affecting hepatocellular carcinoma in steatohepatitis

BACKGROUND & AIMS

With the rising prevalence of alcoholism, obesity and metabolic syndrome, steatohepatitis will become the leading cause of end-stage liver disease and hepatocellular carcinoma in the United States by 2025. Patients with non-alcoholic steatohepatitis and alcoholic liver disease have similar clinical and histopathological presentations, whether these similarities persist in non-alcoholic steatohepatitis and alcoholic liver disease patients with hepatocellular carcinoma remains unknown.

METHODS

A retrospective analysis of the clinical features of adult patients from a large transplant center who underwent liver transplantation for steatohepatitis due to non-alcoholic steatohepatitis and alcoholic causes (alcoholic liver disease) between 1/1/02 and 1/1/12 was performed. Clinical features, explant histopathology, and clinical outcomes were compared.

RESULTS

Hepatocellular carcinoma was present in 80 of 317 patients, who underwent liver transplantation for steatohepatitis with equivalent distribution in non-alcoholic steatohepatitis and alcoholic liver disease patients (24% vs 26%; P = 0.8). On multivariate analysis, significant predictors of hepatocellular carcinoma included age, ethnicity (Hispanic), and diabetes, but not BMI, hypertension or smoking. A lower risk of hepatocellular carcinoma was associated with a clinical history of hyperlipidemia. Clinical parameters were similar between patients with alcoholic liver disease - hepatocellular carcinoma and non-alcoholic steatohepatitis-hepatocellular carcinoma, except sex and presence of metabolic syndrome. non-alcoholic steatohepatitis-hepatocellular carcinoma livers retained histopathological features of non-alcoholic steatohepatitis such as ballooning and Mallory bodies, while alcoholic liver disease-hepatocellular carcinoma livers did not. There were no significant differences in hepatocellular carcinoma recurrence rates or post-transplant overall survival.

CONCLUSIONS

We report the largest single-center study evaluating clinical, histopathological and outcome measures of patients undergoing liver transplantation for steatohepatitis. Older patients, diabetics, and Hispanics may warrant more frequent cancer screening due to increased risk of hepatocellular carcinoma.

Surface Engineering of Nanoparticles for Targeted Delivery to Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-associated deaths worldwide. There is a lack of efficient therapy for HCC; the only available first-line systemic drug, sorafenib, can merely improve the average survival by two months. Among the efforts to develop an efficient therapy for HCC, nanomedicine has drawn the most attention, owing to its unique features such as high drug-loading capacity, intrinsic anticancer activities, integrated diagnostic and therapeutic functionalities, and easy surface engineering with targeting ligands. Despite its tremendous advantages, no nanomedicine can be effective unless it successfully targets the tumor site, which is a challenging task. In this review, the features of HCC are described, and the physiological hurdles that prevent nanoparticles from targeting HCC are discussed. Then, the surface physicochemical factors of nanoparticles that can influence targeting efficiency are discussed. Finally, a thorough description of the physiological barriers that nanomedicine must conquer before uptake by HCC cells if possible is provided, as well as the surface engineering approaches to nanomedicine to achieve targeted delivery to HCC cells. The physiological hurdles and corresponding solutions summarized in this review provide a general guide for the rational design of HCC targeting nanomedicine systems.

Extraction and analysis of signatures from the Gene Expression Omnibus by the crowd

Gene expression data are accumulating exponentially in public repositories. Reanalysis and integration of themed collections from these studies may provide new insights, but requires further human curation. Here we report a crowdsourcing project to annotate and reanalyse a large number of gene expression profiles from Gene Expression Omnibus (GEO). Through a massive open online course on Coursera, over 70 participants from over 25 countries identify and annotate 2,460 single-gene perturbation signatures, 839 disease versus normal signatures, and 906 drug perturbation signatures. All these signatures are unique and are manually validated for quality. Global analysis of these signatures confirms known associations and identifies novel associations between genes, diseases and drugs. The manually curated signatures are used as a training set to develop classifiers for extracting similar signatures from the entire GEO repository. We develop a web portal to serve these signatures for query, download and visualization.

Nanoparticles for targeted delivery of therapeutics and small interfering RNAs in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the 5^th most common malignancy which is responsible for more than half million annual mortalities; also, it is the third leading cause of cancer related death. Unfavorable systemic side-effects of chemotherapeutic agents and susceptibility to the degradation of small interfering RNAs (siRNAs), which can knock down a specific gene involved in the disease, have hampered their clinical application. So, it could be beneficial to develop an efficient carrier for the stabilization and specific delivery of drugs and siRNA to cells. Targeted nanoparticles have gained considerable attention as an efficient drug and gene delivery system, which is due to their capability in achieving the highest accumulation of cytotoxic agents in tumor tissue, modifiable drug pharmacokinetic- and bio-distribution, improved effectiveness of treatment, and limited side-effects. Recent studies have shed more light on the advantages of novel drug loaded carrier systems vs free drugs. Most of the animal studies have reported improvement in treatment efficacy and survival rate using novel carrier systems. Targeted delivery may be achieved passively or actively. In passive targeting, no ligand as homing device is used, while targeting is achieved by incorporating the therapeutic agent into a macromolecule or nanoparticle that passively reaches the target organ. However, in active targeting, the therapeutic agent or carrier system is conjugated to a tissue or cell-specific receptor which is over-expressed in a special malignancy using a ligand called a homing device. This review covers a broad spectrum of targeted nanoparticles as therapeutic and non-viral siRNA delivery systems, which are developed for enhanced cellular uptake and targeted gene silencing in vitro and in vivo and their characteristics and opportunities for the clinical applications of drugs and therapeutic siRNA are discussed in this article. Asialoglycoprotein receptors, low-density lipoprotein, ganglioside GM1 cell surface ligand, epidermal growth factor receptor receptors, monoclonal antibodies, retinoic acid receptors, integrin receptors targeted by Arg-Gly-Asp peptide, folate, and transferrin receptors are the most widely studied cell surface receptors which are used for the site specific delivery of drugs and siRNA-based therapeutics in HCC and discussed in detail in this article.

Prognostic Role and Significance of Paraneoplastic Syndromes in Hepatocellular Carcinoma

Patients with hepatocellular carcinoma (HCC) may develop paraneoplastic syndromes in the clinical course. These syndromes include hypercholesterolemia, hypoglycemia, hypercalcemia, and erythrocytosis, among others. This study was designed to assess the role of prognostic influence of paraneoplastic syndromes in patients with HCC. In a cohort of 175 patients with HCC patients, we compared the clinical features of patients with HCC with or without paraneoplastic syndromes. In addition, survival rates of patients with individual paraneoplastic syndromes and those without were also evaluated. Moreover, factors independently predicting prognosis among patients with HCC with or without paraneoplastic syndromes were analyzed. Among 175 patients with HCC, 54 patients presented paraneoplastic syndromes, and the prevalence was 30.9 per cent. There was no difference of clinical characteristics between patients with HCC with and without paraneoplastic syndromes on diagnosis. However, the patients with paraneoplastic syndromes had a significantly less survival rate comparing with those without during a 5-year follow-up. Cox regression analysis demonstrated that high Child-Pugh grade, large tumor size, portal vein tumor thrombosis, and distant metastasis were all independent unfavorable prognostic factors for survival of patients with HCC. Paraneoplastic syndromes as independent risk factors play a significant role in the progress of HCC and lead to poor prognosis in patients with HCC.

Epidemiology and prognosis of paraneoplastic syndromes in hepatocellular carcinoma

Background. Paraneoplastic syndromes (PNS) such as hypercalcaemia, hypercholesterolaemia, and erythrocytosis have been described in hepatocellular carcinoma (HCC). Aims. (1) To examine the prevalence, clinical characteristics, and survival of PNS in HCC patients and (2) to evaluate the extent to which each individual PNS impacts on patient survival. Methods. We prospectively evaluated the prevalence, clinical characteristics, and survival of PNS among 457 consecutive HCC patients seen in our department over a 10-year period and compared them with HCC patients without PNS. Results. PNS were present in 127 patients (27.8%). The prevalence of paraneoplastic hypercholesterolemia, hypercalcemia, and erythrocytosis 24.5%, 5.3%, and 3.9%, respectively. Patients with PNS had significantly higher alpha-fetoprotein levels, more advanced TNM stage, and shorter survival. Among the individual PNS, hypercalcemia and hypercholesterolemia were associated with more advanced disease and reduced survival but not erythrocytosis. On multivariate analysis, the presence of PNS was not found to be an independent prognostic factor for reduced HCC survival. Conclusion. PNS are not uncommon in HCC and are associated with poor prognosis and reduced survival due to their association with increased tumor burden. However, they do not independently predict poor survival. Individual PNS impact differently on HCC outcome; paraneoplastic hypercalcemia in particular is associated with poor outcome.

Elevated paraneoplastic hypercholesterolemia in a case of hepatoid adenocarcinoma of the stomach with liver metastasis

A 67-year-old man was admitted to our hospital because of a large liver tumor revealed by ultrasonography. Laboratory data showed increased serum levels of alpha-fetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP), which are tumor markers for hepatocellular carcinoma. In addition, the serum cholesterol level was extremely high. Endoscopic examination revealed advanced gastric cancer. Histological findings of the stomach and liver tumor showed they were both hepatoid adenocarcinomas and were both positive for antibodies against AFP as well as DCP, suggesting that the tumors were gastric cancer with liver metastasis. Moreover, 3-hydroxyl-3-methylglutaryl coenzyme A (HMG-CoA) reductase, a key enzyme for regulation of cholesterol synthesis, was upregulated in the tumor tissues. Accordingly, we diagnosed this patient with AFP- and DCP-producing gastric cancer accompanied by paraneoplastic hypercholesterolemia. Paraneoplastic hypercholesterolemia is sometimes seen in hepatocellular carcinoma, but never in gastric cancer. This case is interesting because of the feature of hepatoid adenocarcinoma.

3-Hydroxyl-3-methylglutaryl-coenzyme A reductase is up regulated in hepatocellular carcinoma associated with paraneoplastic hypercholesterolemia

Hepatocellular carcinoma (HCC) is frequently associated with paraneoplastic hypercholesterolemia. However, cholesterol overproduction in HCC tissue has never been demonstrated. An aim of this study is to prove cholesterol overproduction in the HCC tissue of patients with paraneoplastic hypercholesterolemia. Six patients with HCC associated with paraneoplastic hypercholesterolemia and three control patients with HCC who did not have hypercholesterolemia were investigated regarding the expression of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase in HCC tissue by means of immunohistochemical technique. In HCC associated with paraneoplastic hypercholesterolemia, HMG-CoA reductase was clearly stained in cancer cells whereas surrounding non-tumorous hepatocytes showed only slight expression of HMG-CoA reductase. In contrast, HCC tissues derived from patients without paraneoplastic hypercholesterolemia showed only slight expression of HMG-CoA reductase whereas surrounding non-tumorous hepatocytes showed a clear expression of HMG-CoA reductase. We morphologically proved cholesterol overproduction in HCC tissue derived from patients with paraneoplastic hypercholesterolemia. Immunohistochemistry for HMG-CoA reductase thought to be useful in the diagnosis of paraneoplastic hypercholesterolemia.

Low level of low-density lipoprotein receptor-related protein 1 predicts an unfavorable prognosis of hepatocellular carcinoma after curative resection

BACKGROUND

Low-density lipoprotein receptor-related protein 1 (LRP1) is a multifunctional receptor involved in receptor-mediated endocytosis and cell signaling. The aim of this study was to elucidate the expression and mechanism of LRP1 in hepatocellular carcinoma (HCC).

METHODS

LRP1 expression in 4 HCC cell lines and 40 HCC samples was detected. After interruption of LRP1 expression in a HCC cell line either with specific lentiviral-mediated shRNA LRP1 or in the presence of the LRP1-specific chaperone, receptor-associated protein (RAP), the role of LRP1 in the migration and invasion of HCC cells was assessed in vivo and in vitro, and the expression of matrix metalloproteinase (MMP) 9 in cells and the bioactivity of MMP9 in the supernatant were assayed. The expression and prognostic value of LRP1 were investigated in 327 HCC specimens.

RESULTS

Low LRP1 expression was associated with poor HCC prognosis, with low expression independently related to shortened overall survival and increased tumor recurrence rate. Expression of LRP1 in non-recurrent HCC samples was significantly higher than that in early recurrent samples. LRP1 expression in HCC cell lines was inversely correlated with their metastatic potential. After inhibition of LRP1, low-metastatic SMCC-7721 cells showed enhanced migration and invasion and increased expression and bioactivity of MMP9. Correlation analysis showed a negative correlation between LRP1 and MMP9 expression in HCC patients. The prognostic value of LRP1 expression was validated in the independent data set.

CONCLUSIONS

LRP1 modulated the level of MMP9 and low level of LRP1 expression was associated with aggressiveness and invasiveness in HCCs. LRP1 offered a possible strategy for tumor molecular therapy.