Increased LDL receptor mRNA expression in colon cancer is correlated with a rise in plasma cholesterol levels after curative surgery

Prognostic potential of nutritional risk screening and assessment tools in predicting survival of patients with pancreatic neoplasms: a systematic review

BACKGROUNDS & AIMS

The nutritional evaluation of pancreatic cancer (PC) patients lacks a gold standard or scientific consensus, we aimed to summarize and systematically evaluate the prognostic value of nutritional screening and assessment tools used for PC patients.

METHODS

Relevant studies were retrieved from major databases (PubMed, Embase, Web of Science, Cochrane Library) and searched from January 2010 to December 2023. We performed meta-analyses with STATA 14.0 when three or more studies used the same tool.

RESULTS

This analysis included 27 articles involving 6,060 PC patients. According to a meta-analysis of these studies, poor nutritional status evaluated using five nutritional screening tools Prognostic Nutritional Index (PNI), Geriatric Nutritional Risk Index (GNRI), Controlling Nutritional Status Score (CONUT), Nutrition Risk Screening (NRS2002) and Glasgow Prognostic Score (GPS) was associated with all-cause mortality in PC patients. But Modified Glasgow Prognostic Score (mGPS) did not. Of all tools analyzed, CONUT had the maximum HR for mortality (HR = 1.978, 95%CI 1.345-2.907, P = 0.001).

CONCLUSION

All-cause mortality in PC patients was predicted by poor nutritional status. CONUT may be the best nutritional assessment tool for PC patients. The clinical application value of Short Form Mini Nutritional Assessment (MNA-SF), Generated Subjective Global Assessment (SGA) and Patient-generated Subjective Global Assessment (PG-SGA) in PC patients need to be confirmed. In order to improve patients' nutritional status and promote their recovery, nutritional screening tools can be used.

REGISTRATION

This systematic review was registered at the International Prospective Register of Systematic Reviews (PROSPERO) (number CRD42022376715).

Naples prognostic score may predict overall survival in metastatic pancreatic cancer

INTRODUCTION

Naples prognostic score (NPS) based on nutritional and inflammatory parameters can predict response to chemotherapy and overall survival (OS) in many cancer types. However, its significance in metastatic pancreatic cancer (PC) remains unclear. We evaluated the prognostic significance of the NPS in patients with metastatic PC receiving first line chemotherapy.

METHODS

We retrospectively analyzed 215 patients with metastatic PC receiving first line FOLFIRINOX chemotherapy. NPS's were calculated using pre-chemotherapy laboratory data. Patients were divided into three groups according to their scores (NPS: 0; 1 & 2; 3 & 4 were grouped as 1, 2 and 3, respectively). The association of NPS with clinicopathological features and OS were evaluated.

RESULTS

Median age was 64 years, and median OS was 10.5 months. Hemoglobin levels were lower and Ca-19-9 values were higher with increasing NPS. Frequency of patients with bone and/or liver metastases, and with greater than 5 metastatic focus were higher in group 3. A lower NPS was associated with longer OS. The median OS in groups 1, 2, and 3 were 19.5, 12, and 8 months, respectively, and differed significantly. Univariate analysis revealed effect of NPS (3-4) on OS (HR: 2.38, 1.77-3.19). Other prognostic factors affecting OS were age, ECOG, liver, bone or lymph node metastases, number of metastatic foci (<5 vs >5), de-novo metastatic disease, and serum Ca-19-9 levels. NPS (3-4) was identified as an independent prognostic factor negatively affecting OS (HR: 1.89, 1.34-2.65) in multivariate analysis.

CONCLUSION

NPS may be a useful prognostic marker for the prediction of OS in metastatic PC patients receiving systemic chemotherapy.

Identification of a cholesterol metabolism-related prognostic signature for multiple myeloma

Multiple myeloma (MM) is a prevalent hematological malignancy that poses significant challenges for treatment. Dysregulated cholesterol metabolism has been linked to tumorigenesis, disease progression, and therapy resistance. However, the correlation between cholesterol metabolism-related genes (CMGs) and the prognosis of MM remains unclear. Univariate Cox regression analysis and LASSO Cox regression analysis were applied to construct an overall survival-related signature based on the Gene Expression Omnibus database. The signature was validated using three external datasets. Enrichment analysis and immune analysis were performed between two risk groups. Furthermore, an optimal nomogram was established for clinical application, and its performance was assessed by the calibration curve and C-index. A total of 6 CMGs were selected to establish the prognostic signature, including ANXA2, CHKA, NSDHL, PMVK, SCAP and SQLE. The prognostic signature demonstrated good prognostic performance and correlated with several important clinical parameters, including number of transplants, International Staging System, albumin, beta2-Microglobulin and lactate dehydrogenase levels. The function analysis and immune analysis revealed that the metabolic pathways and immunologic status were associated with risk score. The nomogram incorporating the signature along with other clinical characteristics was constructed and the discrimination was verified by the calibration curve and C-index. Our findings indicated the potential prognostic connotation of cholesterol metabolism in MM. The development and validation of the prognostic signature is expected to aid in predicting prognosis and guiding precision treatment for MM.

Cholesterol reprograms glucose and lipid metabolism to promote proliferation in colon cancer cells

Hypercholesterolemia is often correlated with obesity which is considered a risk factor for various cancers. With the growing population of hypercholesterolemic individuals, there is a need to understand the role of increased circulatory cholesterol or dietary cholesterol intake towards cancer etiology and pathology. Recently, abnormality in the blood cholesterol level of colon cancer patients has been reported. In the present study, we demonstrate that alteration in cholesterol levels (through a high-cholesterol or high-fat diet) increases the incidence of chemical carcinogen-induced colon polyp occurrence and tumor progression in mice. At the cellular level, low-density lipoprotein cholesterol (LDLc) and high-density lipoprotein cholesterol (HDLc) promote colon cancer cell proliferation by tuning the cellular glucose and lipid metabolism. Mechanistically, supplementation of LDLc or HDLc promotes cellular glucose uptake, and utilization, thereby, causing an increase in lactate production by colon cancer cells. Moreover, LDLc or HDLc upregulates aerobic glycolysis, causing an increase in total ATP production through glycolysis, and a decrease in ATP generation by OXPHOS. Interestingly, the shift in the metabolic status towards a more glycolytic phenotype upon the availability of cholesterol supports rapid cell proliferation. Additionally, an alteration in the expression of the molecules involved in cholesterol uptake along with the increase in lipid and cholesterol accumulation was observed in cells supplemented with LDLc or HDLc. These results indicate that colon cancer cells directly utilize the cholesterol associated with LDLc or HDLc. Moreover, targeting glucose metabolism through LDH inhibitor (oxamate) drastically abrogates the cellular proliferation induced by LDLc or HDLc. Collectively, we illustrate the vital role of cholesterol in regulating the cellular glucose and lipid metabolism of cancer cells and its direct effect on the colon tumorigenesis.

Prognostic significance of controlling nutritional status score for patients with gastric cancer: A systematic review and meta‑analysis

There is a need to identify potentially useful biomarker(s) for the prediction of prognostic outcomes in patients diagnosed with gastric cancer. This meta-analysis provided updated evidence on the association of controlling nutritional status (CONUT) score with survival and other clinicopathological outcomes in patients with gastric cancer. PubMed and Scopus databases were systematically searched. The review included studies, observational in design, that were conducted among patients with gastric cancer and had documented the association of CONUT score with outcomes of interest. The primary outcomes of interest were overall survival (OS), cancer-specific survival (CSS) and recurrence-free survival (RFS) along with tumour size and extent (T status), nodal status (N status) and tumour staging (TNM staging). STATA was used for statistical analysis. The meta-analysis was conducted with 17 studies. The 5-year OS [hazard ratio (HR), 1.75; 95% confidence interval (CI): 1.55, 1.96], RFS (HR, 1.58; 95% CI: 1.30, 1.91) and CSS (HR, 1.89; 95% CI: 1.01, 3.52) were comparatively poorer in the high CONUT group, than in low CONUT group. High CONUT score was associated with increased risk of having T3/T4 tumour [odds ratio (OR), 1.64; 95% CI: 1.16, 2.34], N2/N3 nodal status (OR, 1.44; 95% CI: 1.17, 1.77) and stage III/IV tumour (OR, 1.64; 95% CI: 1.43, 1.88). The risk of microvascular invasion (OR, 1.46; 95% CI: 1.20, 1.77) and post-operative complications (OR, 1.64; 95% CI: 1.31, 2.06) was higher in those with high CONUT. There were no differences in the risk of poorly differentiated tumour and need for adjuvant chemotherapy between the two groups. Findings suggested that preoperative assessment of CONUT score may be included in the routine assessment of patients with gastric cancer due to its association with survival and other clinical as well as pathological outcomes.

Finding New Molecular Targets of Two Copper(II)-Hydrazone Complexes on Triple-Negative Breast Cancer Cells Using Mass-Spectrometry-Based Quantitative Proteomics

Breast cancer is the most common cancer in women, with a high incidence estimated to reach 2.3 million by 2030. Triple-Negative Breast Cancer (TNBC) is the greatest invasive class of breast cancer with a poor prognosis, due to the side-effects exerted by the chemotherapy used and the low effectivity of novel treatments. In this sense, copper compounds have shown to be potentially effective as antitumor agents, attracting increasing interest as alternatives to the usually employed platinum-derived drugs. Therefore, the aim of this work is to identify differentially expressed proteins in MDA-MB-231 cells exposed to two copper(II)-hydrazone complexes using label-free quantitative proteomics and functional bioinformatics strategies to identify the molecular mechanisms through which these copper complexes exert their antitumoral effect in TNBC cells. Both copper complexes increased proteins involved in endoplasmic reticulum stress and unfolded protein response, as well as the downregulation of proteins related to DNA replication and repair. One of the most relevant anticancer mechanisms of action found for CuHL1 and CuHL2 was the down-regulation of gain-of-function-mutant p53. Moreover, we found a novel and interesting effect for a copper metallodrug, which was the down-regulation of proteins related to lipid synthesis and metabolism that could lead to a beneficial decrease in lipid levels.

Low-density lipoprotein: a versatile nanoscale platform for targeted delivery

Low-density lipoprotein (LDL) is a small lipoprotein that plays a vital role in controlling lipid metabolism. LDL has a delicate nanostructure with unique physicochemical properties: superior payload capacity, long residence time in circulation, excellent biocompatibility, smaller size, and natural targeting. In recent decades, the superiority and feasibility of LDL particles as targeted delivery carriers have attracted much attention. In this review, we introduce the structure, composition, advantages, defects, and reconstruction of LDL delivery systems, summarize their research status and progress in targeted diagnosis and therapy, and finally look forward to the clinical application of LDL as an effective delivery vehicle.

Cholesterol: An important actor on the cancer immune scene

Based on the structural and signaling roles of cholesterol, which are necessary for immune cell activity, high concentrations of cholesterol and its metabolites not only trigger malignant cell activities but also impede immune responses against cancer cells. To proliferate and evade immune responses, tumor cells overcome environmental restrictions by changing their metabolic and signaling pathways. Overexpression of mevalonate pathway enzymes and low-density lipoprotein receptor cause elevated cholesterol synthesis and uptake, respectively. Accordingly, cholesterol can be considered as both a cause and an effect of cancer. Variations in the effects of blood cholesterol levels on the outcome of different types of cancer may depend on the stage of cancer. However, positive effects of cholesterol-lowering drugs have been reported in the treatment of patients with some malignancies.

Prognostic Value of Combination of Controlling Nutritional Status and Tumor Marker in Patients with Radical Non-Small-Cell Lung Cancer

Background

Controlling nutritional status (CONUT) and tumor markers are associated with prognosis in patients with non-small-cell lung cancer (NSCLC). This study is aimed at exploring the potential usefulness of T-CONUT, constructed by combining CONUT and tumor markers, for NSCLC patients undergoing radical surgery.

Methods

A total of 483 patients with NSCLC underwent radical surgical resection. The receiver characteristic operating curve (ROC) was used to select the tumor marker with the highest predictive performance, and CONUT was combined with this marker to construct the T-CONUT. The Kaplan–Meier method and log-rank test were used to analyze the overall survival (OS), and chi-square analysis was used to analyze the association between T-CONUT and clinicopathological characteristics. The independent risk factors were analyzed by Cox regression. A nomogram was constructed by R studio. Calibration plots, the c-index, and decision curves were evaluated for the performance of the nomogram.

Results

ROC analysis showed that the predictive performance of CYFRA21–1 was better than that of CEA, NSE, and SCC. CYFRA21–1 was selected for combining with CONUT to construct T-CONUT. Elevated T-CONUT indicates poor prognosis of patients. Histological type, pTNM, and T-CONUT are independent risk factors associated with patient prognosis. The areas under the curve of the nomogram for predicting 3- and 5-year OS were 0.760 and 0.761, respectively.

Conclusion

T-CONUT comprising CYFRA21–1 and CONUT can effectively predict the prognosis of NSCLC patients.

Linking Late Endosomal Cholesterol with Cancer Progression and Anticancer Drug Resistance

Cancer cells undergo drastic metabolic adaptions to cover increased bioenergetic needs, contributing to resistance to therapies. This includes a higher demand for cholesterol, which often coincides with elevated cholesterol uptake from low-density lipoproteins (LDL) and overexpression of the LDL receptor in many cancers. This implies the need for cancer cells to accommodate an increased delivery of LDL along the endocytic pathway to late endosomes/lysosomes (LE/Lys), providing a rapid and effective distribution of LDL-derived cholesterol from LE/Lys to other organelles for cholesterol to foster cancer growth and spread. LDL-cholesterol exported from LE/Lys is facilitated by Niemann–Pick Type C1/2 (NPC1/2) proteins, members of the steroidogenic acute regulatory-related lipid transfer domain (StARD) and oxysterol-binding protein (OSBP) families. In addition, lysosomal membrane proteins, small Rab GTPases as well as scaffolding proteins, including annexin A6 (AnxA6), contribute to regulating cholesterol egress from LE/Lys. Here, we summarize current knowledge that links upregulated activity and expression of cholesterol transporters and related proteins in LE/Lys with cancer growth, progression and treatment outcomes. Several mechanisms on how cellular distribution of LDL-derived cholesterol from LE/Lys influences cancer cell behavior are reviewed, some of those providing opportunities for treatment strategies to reduce cancer progression and anticancer drug resistance.

The Controlling Nutritional Status (CONUT) Score and Prognosis in Malignant Tumors: A Systematic Review and Meta-Analysis

Increasing evidences indicate that the controlling nutritional status (CONUT) score is associated with cancer prognosis. This study was conducted to investigate the prognostic significance of pretreatment CONUT score on patients with various malignant tumors. The correlation between CONUT score and clinical outcomes of tumor patients were studied by electronic literature retrieval. Pooled hazard ratios (HR), odds ratios (OR) and 95% confidence intervals (95% CI) were calculated to clarify the conclusion. Subgroup analysis were conducted in line with cancer type, cancer stage, treatment, sample size and cut-off value. A total of 62 studies involving 25224 patients were included in this study. Pooled analysis showed that higher CONUT scores were associated with shorter overall survival (HR 1.62, 95% CI 1.45-1.79, p < 0.001), cancer-specific survival (HR 1.80, 95% CI 1.48-2.13, p < 0.001), progress/recurrence-free survival (HR 1.54, 95% CI 1.23-1.85, p < 0.001) and disease-free survival (HR 1.56, 95% CI 1.39-1.74, p < 0.001). In addition, high CONUT score was correlated to higher incidence of postoperative complications (OR 1.64, 95% CI 1.38-1.95, p < 0.001) and mortality (OR 4.22, 95% CI 2.22-8.02, p < 0.001). Consequently, the pretreatment CONUT score is a valuable indicator to predict the clinical outcomes of patients with various malignant tumors.

Lipoproteins as Markers for Monitoring Cancer Progression

Lipoproteins are among the contributors of energy for the survival of cancer cells. Studies indicate there are complex functions and metabolism of lipoproteins in cancer. The current review is aimed at providing updates from studies related to the monitoring of lipoproteins in different types of cancer. This had led to numerous clinical and experimental studies. The review covers the major lipoproteins such as LDL cholesterol (LDL-C), oxidized low-density lipoprotein cholesterol (oxLDL-C), very low-density lipoprotein cholesterol (VLDL-C), and high-density lipoprotein cholesterol (HDL-C). This is mainly due to increasing evidence from clinical and experimental studies that relate association of lipoproteins with cancer. Generally, a significant association exists between LDL-C with carcinogenesis and high oxLDL with metastasis. This warrants further investigations to include Mendelian randomization design and to be conducted in a larger population to confirm the significance of LDL-C and its oxidized form as prognostic markers of cancer.

Can non-cholesterol sterols indicate the presence of specific dysregulation of cholesterol metabolism in patients with colorectal cancer?

Colorectal cancer (CRC) is a highly prevalent malignancy. Previous studies suggested that cholesterol might play a signficant role in malignant transformation and proliferation. Non-cholesterol sterols (NCS), which are transported by serum lipoproteins alongside cholesterol, are regarded as cholesterol synthesis and absorption markers. Quantification of NCS in serum and HDL fraction (NCS_HDL), could provide a better insight into the cholesterol metabolism. The aim of this study was to examine the status of cholesterol synthesis and cholesterol absorption markers in serum and HDL fraction and explore their interrelation in CRC patients. Current study was designed as observational, case-control study. The study included 73 CRC patients and 95 healthy subjects. NCS and NCS_HDL concentrations were determined by HPLC-MS/MS. Based on NCS and NCS_HDL concentrations, different cholesterol homeostasis indices were calculated. Patients had significantly lower NCS (P<0.001) and NCS_HDL concentrations (P<0.001 for desmosterol_HDL; P<0.05 for lathosterol_HDL, P=0.001 for campesterol_HDL, P<0.001 for β-sitosterol_HDL). NCS_HDL/NCS (P<0.005 for desmosterol_HDL/desmosterol; P<0.05 for lathosterol_HDL/lathosterol; P<0.001 for both β-sitosterol_HDL/β-sitosterol and campesterol_HDL/campesterol) and synthesis to absorption ratio (CSI/CAI) (P<0.005) were increased in CRC patients. Additionally, low serum concentrations of desmosterol (P<0.001; OR=0.329; 95%CI (0.199-0.542)) and campesterol (P<0.001; OR=0.540; 95%CI (0.424-0.687)) were independent predictors of CRC presence. Our data suggest that cholesterol homeostasis in CRC is shifted towards increased synthesis. Relative abundance of NCS in HDL particles is increased, suggesting the possible overproduction of cholesterol precursors in peripheral tissues.

Influence of cholesterol on cancer progression and therapy

•

Abnormality in blood cholesterol level is significantly correlated with risk of different cancers.

•

Majority of tumor tissue from cancer patient exhibits overexpression of LDLR and ACAT for supporting rapid cancer cell proliferation.

•

Alteration of the cholesterol metabolism in cancer cells hampers therapeutic response.

•

Targeting cholesterol metabolism for treatment of cancer with other conventional chemotherapeutic drugs appears to be beneficial.

Cholesterol is a fundamental molecule necessary for the maintenance of cell structure and is vital to various normal biological functions. It is a key factor in lifestyle-related diseases including obesity, diabetes, cardiovascular disease, and cancer. Owing to its altered serum chemistry status under pathological states, it is now being investigated to unravel the mechanism by which it triggers various health complications. Numerous clinical studies in cancer patients indicate an alteration in blood cholesterol level (either decreased or increased) in comparison to normal healthy individuals. This article elaborates on our understanding as to how cholesterol is being hijacked in the malignancy for the development, survival, stemness, progression, and metastasis of cancerous cells. Also, it provides a glimpse of how cholesterol derived entities, alters the signaling pathway towards their advantage. Moreover, deregulation of the cholesterol metabolism pathway has been often reported to hamper various treatment strategies in different cancer. In this context, attempts have been made to bring forth its relevance in being targeted, in pre-clinical and clinical studies for various treatment modalities. Thus, understanding the role of cholesterol and deciphering associated molecular mechanisms in cancer progression and therapy are of relevance towards improvement in the management of various cancers.

Reduction of Squalene Epoxidase by Cholesterol Accumulation Accelerates Colorectal Cancer Progression and Metastasis

BACKGROUND & AIMS

Squalene epoxidase (SQLE), a rate-limiting enzyme in cholesterol biosynthesis, is suggested as a proto-oncogene. Paradoxically, SQLE is degraded by excess cholesterol, and low SQLE is associated with aggressive colorectal cancer (CRC). Therefore, we studied the functional consequences of SQLE reduction in CRC progression.

METHODS

Gene and protein expression data and clinical features of CRCs were obtained from public databases and 293 human tissues, analyzed by immunohistochemistry. In vitro studies showed underlying mechanisms of CRC progression mediated by SQLE reduction. Mice were fed a 2% high-cholesterol or a control diet before and after cecum implantation of SQLE genetic knockdown/control CRC cells. Metastatic dissemination and circulating cancer stem cells were demonstrated by in vivo tracking and flow cytometry analysis, respectively.

RESULTS

In vitro studies showed that SQLE reduction helped cancer cells overcome constraints by inducing the epithelial-mesenchymal transition required to generate cancer stem cells. Surprisingly, SQLE interacted with GSK3β and p53. Active GSK3β contributes to the stability of SQLE, thereby increasing cell cholesterol content, whereas SQLE depletion disrupted the GSK3β/p53 complex, resulting in a metastatic phenotype. This was confirmed in a spontaneous CRC metastasis mice model, where SQLE reduction, by a high-cholesterol regimen or genetic knockdown, strikingly promoted CRC aggressiveness through the production of migratory cancer stem cells.

CONCLUSIONS

We showed that SQLE reduction caused by cholesterol accumulation aggravates CRC progression via the activation of the β-catenin oncogenic pathway and deactivation of the p53 tumor suppressor pathway. Our findings provide new insights into the link between cholesterol and CRC, identifying SQLE as a key regulator in CRC aggressiveness and a prognostic biomarker.

Use of preoperative controlling nutritional status (CONUT) score as a better prognostic marker for distal cholangiocarcinoma after pancreatoduodenectomy

PURPOSE

The controlling nutritional status (CONUT) score can be easily calculated from the serum albumin concentration, total cholesterol concentration, and total lymphocyte count. The study aim was to assess the preoperative prognostic factors for the overall survival (OS) of distal cholangiocarcinoma (DCC) following pancreatoduodenectomy (PD) and to demonstrate the utility of the CONUT score.

METHODS

A total of 149 consecutive patients who underwent PD for DCC between September 2002 and December 2016 were divided into a low-CONUT (LC) group (CONUT scores ≤ 2) and a high-CONUT (HC) group (CONUT scores ≥ 3). The clinicopathological characteristics and OS of the patients were evaluated retrospectively. Prognostic factors of DCC were identified by multivariate analyses.

RESULTS

The LC and HC groups included 113 and 36 patients, respectively. The OS was better in the LC group than in the HC group (median survival time and 5 year survival rate: 82 months and 56.8% vs. 38 months and 27.6%, P = 0.005). Multivariate analyses for the OS in all patients showed that the tumor differentiation, perineural invasion, residual tumor status, portal vein resection, blood transfusion, and preoperative CONUT score ≥ 3 were independently associated with a poor survival.

CONCLUSION

The CONUT score may be a useful preoperative factor for predicting the long-term survival in patients with DCC.

The preoperative controlling nutritional status (CONUT) score is an independent prognostic marker for pancreatic ductal adenocarcinoma

The controlling nutritional status (CONUT) score was developed as a nutritional score that can be calculated from the serum albumin level, total cholesterol concentration, and total lymphocyte count. The aim of this study was to assess the prognostic factors for the overall survival (OS) of pancreatic cancer patients following a curative resection and to compare the CONUT score with other prognostic factors to demonstrate its utility. Between January 2007 and December 2015, 307 consecutive patients who underwent surgery for pancreatic ductal adenocarcinoma (PDAC) were divided into a low CONUT group (LC; CONUT score ≤ 3) and a high CONUT group (HC; CONUT score ≥ 4) according to the results of their preoperative blood examination. The clinicopathological characteristics and prognosis of the patients were evaluated retrospectively. The prognostic factors of PDAC were detected using multivariate analyses. The LC and HC groups included 279 and 28 patients, respectively. The overall survival of the LC group was better than that of the HC group (LC, median survival time [MST] 27.9 months, 5-year survival rate 33.4%, respectively; HC, 13.9 months, 6.7%, p < 0.001). The multivariate analyses showed that age ≥ 70 years, lymph node metastasis, absence of postoperative adjuvant chemotherapy, CA19-9 ≥ 200 U/ml, and a preoperative CONUT score ≥ 4 were independently associated with poor survival. However, the Glasgow prognostic score, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio and prognostic nutritional index were not significant factors. The CONUT score may be useful for predicting the long-term survival of patients with PDAC.

Controlling Nutritional Status (CONUT) score is a prognostic factor in patients with resected breast cancer

The present study aimed to determine the correlation between controlling nutritional status (CONUT) and prognosis in resected breast cancer patients. Totally, 861 breast cancer patients with surgical resection in West China Hospital of Sichuan University between 2007 and 2010 were included. The relationship between CONUT and various clinicopathological factors as well as prognosis was evaluated. The results showed that the optimal cutoff value for CONUT to predict the 5-year survival was 3 and CONUT had a higher area under the ROC curve (AUC) for 5-year disease free survival (DFS) and overall survival (OS) prediction compared with the neutrophil lymphocyte ratio (NLR) and prognostic nutritional index (PNI). High CONUT was significantly correlated with older age, lymph node involvement, advanced T-stage, and surgery type. In the multivariate analysis, CONUT-high patients had worse DFS and OS, when compared with CONUT-low patients. In conclusion, preoperative CONUT is a useful marker for predicting long term outcomes in breast cancer patients after curative resection.

High Preoperative Controlling Nutritional Status Score Predicts a Poor Prognosis in Patients with Localized Upper Tract Urothelial Cancer: A Propensity Score Matching Study in a Large Chinese Center

Purpose

The aim of this study was to elucidate the prognostic value of the preoperative controlling nutritional status (CONUT) score, a new index based on the total lymphocyte count, serum albumin concentration and total cholesterol concentration, in patients with localized upper tract urothelial cancer (UTUC) after radical nephroureterectomy (RNU) using propensity score matching (PSM) analysis.

Methods

We retrospectively reviewed 908 consecutive patients with localized UTUC who underwent RNU between 1999 and 2015. Patients were divided into two groups according to the optimal cutoff value of the preoperative CONUT score. Relationships between the CONUT score with clinicopathological characteristics, overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS) were analyzed before and after 1:1 PSM.

Results

A high preoperative CONUT score was significantly correlated with older age, low body mass index (BMI), poor American Statistical Association (ASA) score, advanced pathological T stage, and tumor squamous or glandular differentiation (all p<0.05). Kaplan-Meier curves showed poor OS, CSS, and DFS for patients with a high CONUT score before and after PSM (all p<0.001). Furthermore, multivariate analyses revealed that a high preoperative CONUT score was an independent risk factor for poor DFS (hazard ratio [HR] 1.418, 95% confidence interval [CI] 1.132–1.776, p=0.002) before PSM and an independent risk factor for poor DFS (HR 1.333, 95% CI 1.010–1.760, p=0.042) and OS (HR 1.459, 95% CI 1.010–2.107, p=0.044) after PSM.

Conclusion

A high preoperative CONUT score is an independent prognostic factor for poor outcomes in patients with localized UTUC after RNU.

Lipoprotein Drug Delivery Vehicles for Cancer: Rationale and Reason

Lipoproteins are a family of naturally occurring macromolecular complexes consisting amphiphilic apoproteins, phospholipids, and neutral lipids. The physiological role of mammalian plasma lipoproteins is to transport their apolar cargo (primarily cholesterol and triglyceride) to their respective destinations through a highly organized ligand-receptor recognition system. Current day synthetic nanoparticle delivery systems attempt to accomplish this task; however, many only manage to achieve limited results. In recent years, many research labs have employed the use of lipoprotein or lipoprotein-like carriers to transport imaging agents or drugs to tumors. The purpose of this review is to highlight the pharmacologic, clinical, and molecular evidence for utilizing lipoprotein-based formulations and discuss their scientific rationale. To accomplish this task, evidence of dynamic drug interactions with circulating plasma lipoproteins are presented. This is followed by epidemiologic and molecular data describing the association between cholesterol and cancer.

The prognostic value of preoperative controlling nutritional status score in non-metastatic renal cell carcinoma treated with surgery: a retrospective single-institution study

Purpose

This study aimed to investigate the significance of the controlling nutritional status (CONUT) score as a predictor for survival outcomes for non-metastatic renal cell carcinoma (RCC) patients.

Methods

We retrospectively reviewed 325 patients who received surgical treatment for renal cell carcinoma between 2010 and 2012 at Peking University First Hospital. Patients were divided into two groups according to the optimal cut-off value of CONUT score. Kaplan–Meier method and log-rank test were used for survival analysis according to different CONUT groups. Cox proportional hazards regression models were performed to assess the prognostic value of clinicopathological parameters for overall survival (OS), cancer-specific survival (CSS) and disease-free survival (DFS) respectively.

Results

The optimal cut-off value of CONUT score was 3. High CONUT score significantly correlated to higher tumor grade (P<0.001), later pathological T stage (P<0.001) and tumor necrosis (P<0.001). Patients with higher CONUT score had worse OS (HR 5.34, 95% CI 2.29–12.46, P<0.001), CSS (HR 5.51, 95% CI 2.12–14.33, P<0.001) and DFS (HR 4.23, 95% CI 2.16–8.29, P<0.001). In multivariable analysis, high CONUT score was an independent risk factor for OS, CSS and DFS (OS: HR=3.36, 95% CI 1.73–6.56, P<0.001; CSS: HR=3.34, 95% CI 1.59–6.98, P=0.001; DFS: HR=1.85, ]95% CI 1.07–3.21, P=0.029)

Conclusion

Preoperative CONUT score was an independent prognostic factor for OS, CSS and DFS in non-metastatic RCC patients treated with surgery.

Interlink between cholesterol & cell cycle in prostate carcinoma

Background & objectives:

Earlier reports have shown hypocholesterolaemia in cancer patients and high number of lipid rafts in cancer cells. The primary objective of this study was to compare the intracellular cholesterol turnover in non-cancerous (benign) prostatic hyperplasia (BPH) and carcinoma prostate (CAP) with normal prostate cells obtained from patients undergoing radical cystectomy for carcinoma bladder (sham control).

Methods:

ELISA-based estimation of prostate-specific antigen (PSA), evaluation of expression of low-density lipoprotein receptor (LDLR), peripheral-type benzodiazepine receptor (PBR) and cyclin E, immunohistochemistry and confocal microscopy, measurement of integrated optical density of the diaminobenzidine (DAB)-stained immunohistograms, isolation of nucleus and cell cytoplasm from prostate tissue by ultracentrifugation followed by estimation of cholesterol spectrophotometrically in isolated nuclear and cytoplasmic fractions were performed.

Results:

Seventy five individuals, 25 for each group (BPH n=25; CAP n=25 and sham control n=25), were included in the study. Cholesterol was increased in the cytoplasm and nucleus of the prostate cancer cells along with elevated expression of LDLR. Increased cholesterol concentration in the cell nucleus was found comparable with the increased expression of cholesterol transporter viz. PBR in the prostate tumour tissues as compared to its expression in normal prostate cells obtained from individuals undergoing radical cystectomy for carcinoma bladder. Cell cycle protein cyclin E was also highly expressed in cancer tissues.

Interpretation & conclusions:

The present findings along with increased expression of cell cycle protein cyclin E in the cell nucleus of the tumour tissue suggested the possibility of an intriguing role of cholesterol in the mechanism of cell cycle process of prostate cell proliferation.

Impact of the Controlling Nutritional Status Score on the Prognosis After Curative Resection of Pancreatic Ductal Adenocarcinoma

OBJECTIVES

The controlling nutritional status (CONUT) score is a useful tool to evaluate immune-nutritional status. This study aimed to investigate the impact of the CONUT score on short- and long-term outcomes after curative resection of pancreatic ductal adenocarcinoma (PDAC).

METHODS

Consecutive 344 PDAC patients receiving pancreatectomy without neoadjuvant therapy were examined retrospectively. After the best predictive value of the CONUT score for survival was identified, association between the CONUT score and long-term outcomes was evaluated using log-rank tests and a Cox regression model. Then correlations between the CONUT score and postoperative complications were analyzed.

RESULTS

The optimal cutoff value of the CONUT score was 4. The high CONUT score group showed significantly lower overall survival than the low CONUT score group (P = 0.002). In contrast, no significant difference in recurrence-free survival was found (P = 0.43). A multivariate analysis demonstrated that high CONUT score had an independent association with overall survival (hazard ratio, 1.64; P = 0.003). The CONUT score showed no association with postoperative pancreatic fistula, Clavien-Dindo grade, or postoperative hospital stay.

CONCLUSION

The CONUT score had an independent association with survival in patients with PDAC after pancreatectomy and was not associated with recurrence or postoperative complications.

Lipoproteins for therapeutic delivery: recent advances and future opportunities

The physiological role(s) of mammalian plasma lipoproteins is to transport hydrophobic molecules (primarily cholesterol and triacylglycerols) to their respective destinations. Lipoproteins have also been studied as drug-delivery agents due to their advantageous payload capacity, long residence time in the circulation and biocompatibility. The purpose of this review is to briefly discuss current findings with the focus on each type of formulation's potential for clinical applications. Regarding utilizing lipoprotein type formulation for cancer therapeutics, their potential for tumor-selective delivery is also discussed.

CONUT: a novel independent predictive score for colorectal cancer patients undergoing potentially curative resection

BACKGROUND

Controlling nutritional status (CONUT) score, calculated from serum albumin and total cholesterol concentrations and total lymphocyte count, is reportedly valuable for nutritional assessment. This study investigated whether CONUT score was predictive of outcomes in colorectal cancer (CRC) patients undergoing surgical resection.

METHODS

Preoperative CONUT scores were retrospectively evaluated in 417 CRC patients who underwent potentially curative resection at Kumamoto University Hospital from March 2005 to August 2014. Patients were divided into four groups based on preoperative CONUT scores: normal, light, moderate, and severe. The associations of CONUT score with clinicopathological factors, patient survival, and postoperative complications were examined.

RESULTS

CONUT score correlated significantly with age (P < 0.001), body mass index (P = 0.005), carcinoembryonic antigen (P = 0.002), and carbohydrate antigen 19-9 (P = 0.005) concentrations. Overall survival (OS) rate was significantly lower in patients with moderate/severe than light or normal CONUT scores. CONUT score was independently prognostic of OS [moderate/severe vs. normal, hazard ratio = 5.92, 95 % confidence interval (CI) 2.30-14.92; P < 0.001)]. Patients with moderate/severe CONUT scores were at greater risk for complications, especially for severe complications. Multivariate analysis showed that CONUT score was independently predictive of severe complications (moderate/severe vs. normal, odds ratio = 4.51, 95 % CI 1.89-10.74; P < 0.001).

CONCLUSIONS

CONUT score may predict survival and postoperative severe complications in CRC patients undergoing potentially curative resection. Management of CRC patients may need consideration of host nutritional status.

The pretreatment Controlling Nutritional Status (CONUT) score is an independent prognostic factor in patients with resectable thoracic esophageal squamous cell carcinoma: results from a retrospective study

BACKGROUND

The purpose of this study was to investigate the impact of the Controlling Nutritional Status (CONUT) score on survival compared with the platelet to lymphocyte ratio (PLR), the neutrophil to lymphocyte ratio (NLR), and the Glasgow Prognostic Score (GPS) in patients with resectable thoracic esophageal squamous cell carcinoma (ESCC).

METHODS

One hundred eighty-five consecutive patients who underwent subtotal esophagectomy with curative intent for resectable thoracic ESCC were retrospectively reviewed. Time-dependent receiver operating characteristic curve analyses for 3-year overall survival (OS) as the endpoint were performed, and the maximal Youden indices were calculated to assess discrimination ability and to determine the appropriate cut-off values of CONUT, PLR, and NLR. The patients were then classified into high and low groups based on these cut-off values. Correlations between CONUT and other clinicopathological characteristics were analyzed. Prognostic factors predicting overall survival (OS) and relapse-free survival (RFS) were analyzed using Cox proportional hazards models.

RESULTS

The areas under the curve predicting 3-year OS were 0.603 for CONUT, 0.561 for PLR, 0.564 for NLR, and 0.563 for GPS. The optimal cut-off values were two for the CONUT score, 193 for PLR, and 3.612 for NLR. The high-CONUT group was significantly associated with lower BMI, high-PLR, high-NLR, and GPS1/2 groups. On univariate analysis, high-CONUT, high-PLR, high-NLR, and GPS 1/2 groups were significantly associated with poorer OS and RFS. Of these factors, multivariate analysis revealed that only the CONUT score was an independent prognostic factor for OS (HR 2.303, 95 % CI 1.191-4.455; p = 0.013) and RFS (HR 2.163, 95 % CI 1.139-4.109; p = 0.018).

CONCLUSIONS

The CONUT score was an independent predictor of OS and RFS before treatment and was superior to PLR, NLR, and GPS in terms of predictive ability for prognosis in patients with resectable thoracic ESCC.

Impact of the Preoperative Controlling Nutritional Status (CONUT) Score on the Survival after Curative Surgery for Colorectal Cancer

Background

Recently, the preoperative immune-nutritional status has been reported to correlate with the survival rate in patients with colorectal cancer (CRC). However, there have been no reports on the relationship between the controlling nutritional status (CONUT) score and the clinical outcome after curative surgery for CRC. We herein evaluated the prognostic significance of the CONUT score in patients with CRC, and then compared the accuracy of the CONUT score and the prognostic nutritional index (PNI) as a predictor of survival.

Methods

We retrospectively reviewed a database of 204 patients who underwent curative surgery for Stage II/III CRC. Patients were divided into two groups according to the CONUT score and the PNI.

Results

The five-year cancer-specific survival (CSS) rate was significantly higher at 92.7% in the low CONUT group, compared to a rate of 81.0% in the high CONUT group (p=0.0016). The five-year CSS was 71.2% in the low PNI group and 92.3% in the high PNI group, which showed a significant difference (p=0.0155). A multivariate analysis showed that lymph node metastasis and the CONUT score were independent risk factors for CSS.

Conclusion

This study suggested that the CONUT score is a strong independent predictor of the survival among CRC patients.

Synthetic high-density lipoprotein-like nanoparticles as cancer therapy

High-density lipoproteins (HDL) are diverse natural nanoparticles that carry cholesterol and are best known for the role that they play in cardiovascular disease. However, due to their unique targeting capabilities, diverse molecular cargo, and natural functions beyond cholesterol transport, it is becoming increasingly appreciated that HDLs are critical to cancer development and progression. Accordingly, this chapter highlights ongoing research focused on the connections between HDL and cancer in order to design new drugs and targeted drug delivery vehicles. Research is focused on synthesizing biomimetic HDL-like nanoparticles (NP) that can be loaded with diverse therapeutic cargo (e.g., chemotherapies, nucleic acids, proteins) and specifically targeted to cancer cells. Beyond drug delivery, new data is emerging that HDL-like NPs may be therapeutically active in certain tumor types, for example, B cell lymphoma. Overall, HDL-like NPs are becoming increasingly appreciated as targeted, biocompatible, and efficient therapies for cancer, and may soon become indispensable agents in the cancer therapeutic armamentarium.

Synthetic high-density lipoprotein-like nanoparticles for cancer therapy

High-density lipoproteins (HDLs) are a diverse group of natural nanoparticles that are most well known for their role in cholesterol transport. However, HDLs have diverse functions that provide significant opportunities for cancer therapy. Presented is a focused review of the ways that synthetic versions of HDL have been used as targeted therapies for cancer, and as vehicles for the delivery of diverse therapeutic cargo to cancer cells. As such, synthetic HDLs are likely to play a central role in the development of next-generation cancer therapies.

Low Density Lipid Nanoparticles for Solid Tumor Targeting

One of the most significant characteristics of cancer cells is their rapid dividing ability and overexpression of LDL receptors, which offers an opportunity for the selective targeting of these cells. 5-Fluorouracil (5-FU)-encapsulated low density lipid nanoparticles (LDLN) were prepared by the emulsion congealing method which mimics the plasma-derived LDL by acquiring the apolipoprotein B-100 from the blood. The average particle size, transmission electron microscope (TEM), and drug content of the prepared LDLN dispersion were found to be 161±3.5 nm, with spherical shape, and 0.370±0.05 mg/mL, respectively. In vitro release studies revealed a sustained profile which decreased with a lapse of time. In vivo studies of 5-FU serum concentration and biodistribution revealed a 5-FU serum concentration of 8.5% in tumor cells and about 2.1% in the liver at the end of 24 hr from LDLN. Tumor growth suppression studies showed 185.42% average tumor growth and 89.76% tumor height as compared to the control exhibiting tumor growth at 1166.47% and tumor height at 176.07%. On the basis of these collective data, it is suggested that a higher accumulation of LDLN, when given as an IV, in solid tumors is attributed to the active uptake of LDLN via LDL receptors via apolipoprotein B-100.

Contrast agents for preclinical targeted X-ray imaging

Micro-computed tomography (micro-CT) is an X-ray based instrument that it is specifically designed for biomedical research at a preclinical stage for live imaging of small animals. This imaging modality is cost-effective, fast, and produces remarkable high-resolution images of X-ray opaque skeleton. Administration of biocompatible X-ray opaque contrast agent allows delineation of the blood vessels, and internal organs and even detection of tumor metastases as small as 300 μm. However, the main limitation of micro-CT lies in the poor efficacy or toxicity of the contrast agents. Moreover, contrast agents for micro-CT have to be stealth nanoparticulate systems, i.e. preventing their rapid renal clearance. The chemical composition and physicochemical properties will condition their uptake and elimination pathways, and therefore all the biological fluids, organs, and tissues trough this elimination route of the nanoparticles will be contrasted. Furthermore, several technologies playing on the nanoparticle properties, aim to influence these biological pathways in order to induce their accumulation onto given targeted sites, organs of tumors. In function of the methodologies carried out, taking benefit or not of the action of immune system, of the natural response of the organism like hepatocyte uptake or enhanced permeation and retention effect, or even accumulation due to ligand/receptor interactions, the technologies are called passive or active targeted imaging. The present review presents the most recent advances in the development of specific contrast agents for targeted X-ray imaging micro-CT, discussing the recent advance of in vivo targeting of nanoparticulate contrast agents, and the influence of the formulations, nature of the nanocarrier, nature and concentration of the X-ray contrasting materials, effect of the surface properties, functionalization and bioconjugation. The pharmacokinetic and versatility of nanometric systems appear particularly advantageous for addressing the versatile biomedical research needs. State of the art investigations are on going to propose contrast agents with tumor accumulating properties and will contribute for development of safer cancer medicine having detection and therapeutic modalities.

The role of cholesterol metabolism and cholesterol transport in carcinogenesis: a review of scientific findings, relevant to future cancer therapeutics

While the unique metabolic activities of malignant tissues as potential targets for cancer therapeutics has been the subject of several recent reviews, the role of cholesterol metabolism in this context is yet to be fully explored. Cholesterol is an essential component of mammalian cell membranes as well as a precursor of bile acids and steroid hormones. The hypothesis that cancer cells need excess cholesterol and intermediates of the cholesterol biosynthesis pathway to maintain a high level of proliferation is well accepted, however the mechanisms by which malignant cells and tissues reprogram cholesterol synthesis, uptake and efflux are yet to be fully elucidated as potential therapeutic targets. High and low density plasma lipoproteins are the likely major suppliers of cholesterol to cancer cells and tumors, potentially via receptor mediated mechanisms. This review is primarily focused on the role(s) of lipoproteins in carcinogenesis, and their future roles as drug delivery vehicles for targeted cancer chemotherapy.

Prostatic alpha-linolenic acid (ALA) is positively associated with aggressive prostate cancer: a relationship which may depend on genetic variation in ALA metabolism

Previous observational studies have reported associations between prostate cancer and alpha-linolenic acid (ALA). However, few investigations have been able to study this relationship prospectively and in well-controlled settings. Moreover, no studies have determined whether single nucleotide polymorphisms (SNPs) that influence ALA metabolism are associated with this common cancer. The purpose of this study was to explore associations between prostatic levels of ALA, SNPs and prostate cancer-specific biomarkers in samples collected from a previous randomized clinical trial conducted using a presurgical model and which tested the effects of flaxseed supplementation, a rich source of ALA, prior to prostatectomy (n = 134). Serum prostate-specific antigen (PSA) was determined and immunohistochemistry was used to assess tumor proliferation rate (Ki67). Prostatic ALA was determined with gas chromatography. Seven previously identified SNPs associated with delta-6 desaturase activity (rs99780, rs174537, rs174545, rs174572, rs498793, rs3834458 and rs968567) were tested for associations with prostatic ALA, PSA and Ki67. Despite consuming seven times more ALA per day, men in the flaxseed arm had similar amounts of prostatic ALA relative to men not consuming flaxseed. In unadjusted analysis, there were significant positive associations between prostatic ALA and PSA (ρ = 0.191, p = 0.028) and Ki67 (ρ = 0.186, p = 0.037). After adjusting for covariates (flaxseed, age, race, BMI and statin-use) the association between ALA and PSA remained (p = 0.004) but was slightly attenuated for Ki67 (p = 0.051). We did not observe associations between any of the SNPs studied and prostatic ALA; however, in models for PSA there was a significant interaction between rs498793 and ALA and for Ki67 there were significant interactions with ALA and rs99780 and rs174545. Independent and inverse associations were observed between rs174572 and Ki67. This study provides evidence that prostatic ALA, independent of the amount of ALA consumed, is positively associated with biomarkers of aggressive prostate cancer and that genetic variation may modify this relationship.

Optimization of LDL targeted nanostructured lipid carriers of 5-FU by a full factorial design

Background:

Nanostructured lipid carriers (NLC) are a mixture of solid and liquid lipids or oils as colloidal carrier systems that lead to an imperfect matrix structure with high ability for loading water soluble drugs. The aim of this study was to find the best proportion of liquid and solid lipids of different types for optimization of the production of LDL targeted NLCs used in carrying 5-Fu by the emulsification-solvent evaporation method.

Materials and Methods:

The influence of the lipid type, cholesterol or cholesteryl stearate for targeting LDL receptors, oil type (oleic acid or octanol), lipid and oil% on particle size, surface charge, drug loading efficiency, and drug released percent from the NLCs were studied by a full factorial design.

Results:

The NLCs prepared by 54.5% cholesterol and 25% of oleic acid, showed optimum results with particle size of 105.8 nm, relatively high zeta potential of –25 mV, drug loading efficiency of 38% and release efficiency of about 40%. Scanning electron microscopy of nanoparticles confirmed the results of dynamic light scattering method used in measuring the particle size of NLCs.

Conclusions:

The optimization method by a full factorial statistical design is a useful optimization method for production of nanostructured lipid carriers.

Synthesis of octadecylamine-retinoic acid conjugate for enhanced cytotoxic effects of 5-FU using LDL targeted nanostructured lipid carriers

The aim of the present study was to reduce 5-FU side effects by targeted nanostructured lipid carriers (NLCs) to LDL receptors that are over expressed in colorectal carcinoma and also use of a new synthesized conjugate of retinoic acid as a cytotoxic agent. Fatty acyl amide derivative of retinoic acid was synthesized by its conjugation to octadecylamine with the expectation to improve its loading capacity in NLCs of 5-FU. The NLCs were prepared by an emulsification-solvent evaporation method using cholesterol and cholesteryl stearate. Physical properties and drug release were studied in NLCs. The cytotoxicity of NLCs loaded with 5-FU and retinoic acid conjugate was studied on colon cancer cells (HT29) using MTT assay. To confirm that drug targeting has been done through LDL receptors, APO-E was omitted from the cell culture and the MTT assay was repeated. FTIR and (1)H NMR spectra confirmed successful production of the conjugate. Results showed the IC(50) of free 5-FU was about 7.6 μM while in comparable concentration, the cytotoxicity of 5-FU loaded in NLCs containing the retinoic acid conjugate was nearly 2 fold of NLCs just loaded with 5-FU and more than 5 fold of free 5-FU. The retinoic acid conjugate loaded NLCs prepared by cholesterol can target LDL receptors of HT29 cells and seems promising in reducing 5-FU dose in colorectal cancer.

In vitro assessment of poly-iodinated triglyceride reconstituted low-density lipoprotein: initial steps toward CT molecular imaging

RATIONALE AND OBJECTIVES

Targeted molecular probes offer the potential for greater specificity in cancer imaging with contrast-enhanced computed tomography (CT). We investigate a low-density lipoprotein (LDL) nanoparticle loaded with poly-iodinated triglyceride (ITG) in a proof of concept study of targeted x-ray imaging. LDLs are targeted to the LDL cell surface receptor (LDLR), which is overexpressed in several tumor types. The LDL-LDLR pathway presents a high-capacity and self-renewing transport system for molecular imaging in CT.

MATERIALS AND METHODS

ITG was synthesized and loaded into the core of LDL particles to form a reconstituted nanoparticle, hereafter referred to as (rITG)LDL. Particle size was measured by dynamic light scattering. The x-ray attenuation of the (rITG)LDL solution was measured with CT imaging and signal enhancement was calibrated for equivalent iodine concentration. Cultured human hepatoblastoma G2 (HepG2) cells, which overexpress LDLR, were incubated with (rITG)LDL with or without native LDL. The cells were imaged with CT to characterize particle sequestration.

RESULTS

Reconstitution of LDL with ITG was successful and did not compromise the targeting function of the particle. Measurement of the x-ray attenuation properties of the (rITG)LDL solution revealed an effective iodine concentration of 0.78 mg/mL. In vitro studies of HepG2 cells demonstrated a significant increase in CT image intensity over control cells when incubated with (rITG)LDL.

CONCLUSION

The in vitro results of this study suggest that (rITG)LDL can provide adequate image enhancement for CT molecular imaging. Potential applications include breast imaging and small animal imaging at low x-ray energies. In vivo experiments will be required to verify that tumor uptake of (rITG)LDL is sufficient for enhanced detection. Use at higher x-ray energies, as used in conventional CT, will require a further increase in iodine loading.

High-density lipoprotein-based contrast agents for multimodal imaging of atherosclerosis

Lipoproteins, natural nanoparticles, have a well-recognized biological role and are highly suitable as a platform for delivering imaging agents. The ease with which both the exterior and interior of the particles can be modified permits the creation of multifunctional nanoparticles for imaging as well as the delivery of therapeutics. Importantly, their endogenous nature may make them biocompatible and biodegradable and allows them to avoid the recognition of the reticuloendothelial system. In particular, high-density lipoproteins (HDL) are of interest, because of their small size they can easily cross the endothelium and penetrate the underlying tissue. We summarize here the progress in establishing HDL as a vector for delivering a variety of diagnostically active materials to vulnerable atherosclerotic plaques in mouse models of atherosclerosis. By loading various types of image-enhancing compounds into either the core or surface of HDL, they can be visualized by different imaging modalities (MRI, CT, optical). By rerouting of HDL away from plaque macrophages, imaging of biological processes in diseases besides atherosclerosis may also be achieved.

Cholesterol levels in patients with multiple myeloma

Hypocholesterolemia is seen in solid tumors and some hematological malignancies. We assessed cholesterol levels and the relationship between these levels and types and stages of multiple myeloma (MM) in the patients with MM. One-hundred two patients (60 male and 42 female) of mean age 59 +/- 11 years with MM were enrolled to this study. While 71.6% of the patients were Ig G type, 80.4% of the patients were at stage III. In the control group, there were 71 healthy persons (42 male and 29 female) of mean age 58 +/- 8 years. The levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in the patients with MM were significantly lower than the controls (p < 0.001). There was no difference for the levels of very-low-density lipoprotein cholesterol and triglyceride between the two groups (p > 0.05). Lipid parameters were not different between Ig types (p > 0.05). The levels of TC and LDL-C in the patients with stage I were higher than those of stages II and III (p < 0.001 and p < 0.005, respectively). The levels of TC and LDL-C in the controls were not higher than the patients with stage I (p > 0.05). HDL-C levels in the patients with stage III were lower than controls (p < 0.001). Hypocholesterolemia are seen in the patients with MM. Hypocholesterolemia may be due to increased LDL clearance and utilization of cholesterol by myeloma cells.

Low-density lipoprotein nanoparticles as magnetic resonance imaging contrast agents

Low-density lipoproteins (LDLs) are a naturally occurring endogenous nanoplatform in mammalian systems. These nanoparticles (22 nm) specifically transport cholesterol to cells expressing the LDL receptor (LDLR). Several tumors overexpress LDLRs presumably to provide cholesterol to sustain a high rate of membrane synthesis. Amphiphilic gadolinium (Gd)-diethylenetriaminepentaacetic acid chelates have been incorporated into the LDL to produce a novel LDLR-targeted magnetic resonance imaging (MRI) contrast agent. The number of Gd chelates per LDL particle ranged between 150 and 496 Gd(III). In vitro studies demonstrated that Gd-labeled LDL retained a similar diameter and surface charge as the native LDL particle. In addition, Gd-labeled LDL retained selective cellular binding and uptake through LDLR-mediated endocytosis. Finally, Gd-labeled LDLs exhibited significant contrast enhancement 24 hours after administration in nude mice with human hepatoblastoma G2 xenografts. Thus, Gd-labeled LDL demonstrates potential use as a targeted MRI contrast agent for in vivo tumor detection.

Gene transfer into human hepatoma cells by receptor-associated protein/polylysine conjugates

Receptor-associated protein (RAP) is a ligand for all members of low-density lipoprotein (LDL) receptor families. RAP is internalized into cells via receptor-mediated endocytic trafficking, making it an attractive mechanism for efficient gene delivery. In this study, we have developed a gene delivery system using RAP as a targeting ligand. A RAP cDNA lacking a C-terminal heparin-binding domain was amplified by polymerase chain reaction (PCR) from a human liver cDNA library and was reamplified by using a primer containing a cysteine codon at its carboxyl end to facilitate its conjugation to polylysine (polyK). RAP was purified using a bacterial expression system and coupled to poly-D-lysine (PDL) or poly-L-lysine (PLL) of average MW 50 kDa via the heterobifunctional cross-linker SPDP. Using fluorescence-labeled RAP ligand, cellular uptake of the transfection complexes into HepG2 cells was shown to be highly efficient and more specific to PDL-conjugated RAP compared with PLL-conjugated one. Plasmid DNA containing a luciferase reporter gene was condensed with either RAP-PDL or RAP-PLL. In vitro transfection into HepG2 cells with RAP-PDL conjugate resulted in significantly higher luciferase expression levels in comparison to either nonconjugated PDL, or RAP-PLL, or LipofecAMINE/DNA complexes in the presence of 10% fetal bovine serum. Luciferase expression was inhibited by the addition of excess RAP. Treatment of the cells with Lovastatin, which inhibits HMG-Co reductase and increases expression of LDL receptor, stimulates luciferase expression, suggesting that the gene delivery is specifically mediated by LDL receptor. Thus, RAP-PDL conjugates have the potential to be used as a new nonviral gene delivery vector.

MR and fluorescent imaging of low-density lipoprotein receptors

RATIONALE AND OBJECTIVES

Over-expression of low-density lipoprotein receptors (LDLRs) occurs in many types of malignancies and is related to the requirement for lipids for rapid proliferation of the tumors. On the other hand, LDLRs that are unable to bind LDL are found on hepatocytes of patients with familial hypercholesterolemia (FH), a genetic disease that leads to premature atherosclerosis and death. The highly selective binding of LDL to LDLR makes these particles ideal carriers of therapeutic and diagnostic contrast agents into the targeted cells. The objectives of this paper are to examine whether a prototype contrast agent (PTIR267) with dual detection properties is suitable for labeling of LDL particles for in vivo detection of LDLR by magnetic resonance imaging (MRI) and for in vitro monitoring of cellular localization by confocal fluorescence microscopy.

MATERIALS AND METHODS

PTIR267 is a lipophilic GdDTPA derivative conjugated to a fluorescent dye. The conjugated dye molecule makes the probe sufficiently water soluble to allow labeling of LDL by a brief incubation of LDL with PTIR267 dissolved in PBS at 37 degrees C (mole ratio LDL: PTIR267 = 0.09:1). The molar relaxivity of PTIR267 in saline is 26 mM(-1)s(-1). Specific LDLR-mediated uptake of PTIR267-labeled LDL was demonstrated in vitro by confocal fluorescence imaging of B16 melanoma cells using confocal fluorescence imaging. In vivo uptake of PTIR267-labeled LDL by a subcutaneously implanted B16 melanoma in mice leads to 30% decrease in longitudinal relaxation time (T(1)) in the tumor. In vivo uptake of PTIR267-labeled LDL leads to 70% decrease in T(1) in a normal C57BL/6 mouse liver; however, in the liver of LDL receptor gene knockout (LDLr-/-) mice with C57BL/6 background, only 12% decrease in T(1) is observed.

CONCLUSIONS

The dual fluorescence and MR imaging properties of PTIR267, combined with the ease of LDL labeling, suggest that it will be a useful tool for optimization of LDLR-targeted cancer diagnosis or therapy and for monitoring the efficacy of gene therapy of FH.

Sterol-independent regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase in tumor cells

Elevated 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase expression supports synthesis of prenyl pyrophosphate intermediates required for tumor growth. In this study, the copy number of HMG-CoA reductase mRNA was determined in solid tumor and leukemic cell lines using competitive reverse transcriptase-polymerase chain reaction. Reductase mRNA was increased about eight-fold in Caco2 human colon adenocarcinoma cells compared with that in CCD18 normal colon cells. We also found a 50-fold enhancement of reductase mRNA in stimulated human lymphocytes compared with unstimulated cells. In CEM human leukemia cells, reductase mRNA was increased 8.6 times compared with that in stimulated lymphocytes. Greater low density lipoprotein receptor mRNA was also observed in tumor cells compared with normal counterparts. We hypothesized that elevated reductase mRNA was due to attenuation of sterol-mediated control of tumor reductase promoter activity. We first compared the methylation status of CpG dinucleotides in the promoters of reductase and p16 tumor suppressor genes from solid tumor, leukemic, and normal cells. As reported for other tumor cells the p16 promoter region was hypermethylated in Caco2 and CEM cells but was hypomethylated in corresponding normal cells. However, reductase promoter sequences in both normal and tumor cells were hypomethylated, demonstrating that methylation is not involved in sterol-independent reductase regulation. We addressed altered transcription factor binding to the tumor cell reductase promoter by transiently transfecting Caco2 and CCD18 with a plasmid vector containing a hamster HMG-CoA reductase promoter fused to the luciferase gene. We found that increased reductase mRNA was partially due to an approximately three-fold higher reductase promoter activity in Caco2 than in CCD18, measured by luciferase reporter assays. Thus, differential binding of transcription factor or factors on the tumor cell reductase promoter attenuates normal sterol-mediated regulation of reductase activity.

Tumour enhancement with newly developed Mn-metalloporphyrin (HOP-9P) in magnetic resonance imaging of mice

The purpose of the study is to evaluate the tumour enhancing characteristics and biodistribution of a newly developed metalloporphyrin derivative, HOP-9P (13, 17-bis (1-carboxypropionyl) carbamoylethyl-3, 8-bis (1-phenylpropyloxyethyl)-2,7,12,18-tetra- methyl-porphynato manganese (III)). Seven mice bearing SCC VII tumours were imaged using T1-weighted conventional spin echo magnetic resonance images before and 5 min, 2 h and 24 h after intravenous injection of 0.1 mmol/kg of HOP-9P. For the acquired images, signal intensities of the tumour, muscle and oil-phantom were measured. Then, tumor/oil and tumor/muscle signal intensity ratios were calculated. Nineteen mice were sacrificed before or after the administration of HOP-9P (at 5 min, 2 h and 24 h), and the biodistribution of manganese in the tumour, muscle, liver, blood and kidneys was measured using optical emission spectrometers and was expressed as micrograms of manganese per gram of tissue. The tumour/muscle signal intensity ratio at 24 h (3.18 +/- 0.34) was significantly higher than precontrast ratio (1.77 +/- 0.20) (P < 0.05). The biodistribution assessment of manganese demonstrated that HOP-9P gradually and consistently accumulated in the tumour to reach the highest concentration at 24 h (3.49 +/- 1.22 micro gMn/g). It is concluded that HOP-9P is a potential tumour-specific MR contrast agent.

Recombinant lipoproteins: lipoprotein-like lipid particles for drug targeting

Lipoproteins are endogenous particles that transport lipids through the blood to various cell types, where they are recognised and taken up via specific receptors. These particles are, therefore, excellent candidates for the targeted delivery of drugs to various tissues. For example, the remnant receptor and the asialoglycoprotein receptor (ASGPr), which are uniquely localised on hepatocytes, recognise chylomicrons and lactosylated high density lipopoteins (HDL), respectively. In addition, tumour cells of various origins overexpress the low density lipoprotein (LDL) receptor that recognises apolipoprotein E (apoE) on small triglyceride-rich particles and apoB-100 on LDL. Being endogenous, lipoproteins are biodegradable, do not trigger immune reactions, and are not recognised by the reticuloendothelial system (RES). However, their endogenous nature also hampers large-scale pharmaceutical application. In the past two decades, various research groups have successfully synthesised recombinant lipoproteins from commercially available natural and synthetic lipids and serum-derived or recombinant apolipoproteins, which closely mimic the metabolic behaviour of their native counterparts in animal models as well as humans. In this paper, we will summarise the studies that led to the development of these recombinant lipoproteins, and we will address the possibility of using these lipidic particles to selectively deliver a wide range of lipophilic, amphiphilic, and polyanionic compounds to hepatocytes and tumour cells. In addition, the intrinsic therapeutic activities of recombinant chylomicrons and HDL in sepsis and atherosclerosis will be discussed.

The abnormal lipid spectrum in malignant obstructive jaundice in relation to endotoxin sensitivity and the result of preoperative biliary drainage

BACKGROUND

Biliary obstruction changes the spectrum of lipoproteins, which are now known to bind and neutralize endotoxin. Postoperative septic complications related to an increased susceptibility to endotoxin occur frequently in patients with obstructive jaundice. The effect of preoperative biliary drainage on changes in the lipoprotein spectrum and its relation to endotoxin sensitivity was studied.

METHODS

Abnormalities in the lipoprotein spectrum were assessed in 15 patients with malignant obstructive jaundice before and 3 weeks after endoscopic biliary drainage. Changes in endotoxin responsiveness were assessed by using endotoxin-neutralizing reagents (anti-CD14 monoclonal antibody, polymyxin B, and recombinant bactericidal permeability increasing protein) to block cytokine production in whole blood cell cultures that were stimulated by cholestatic plasma taken before and after drainage.

RESULTS

Drainage normalized very-low-density, low-density, and high-density lipoprotein cholesterol fractions from, respectively, 43% to 19%, 50% to 65%, and 6% to 16% (P <.01). Ex vivo stimulation of whole blood with predrainage cholestatic plasma was 20-fold higher (P <.001) than with postdrainage plasma. Blocking the endotoxin response during the stimulation with predrainage cholestatic plasma with anti-CD14 monoclonal antibody, polymyxin B or recombinant bactericidal permeability increasing protein resulted in attenuation of the inflammatory response, reducing tumor necrosis factor-alpha levels at least 5-fold.

CONCLUSIONS

Preoperative biliary drainage normalizes the changed lipid profile and the endotoxin-stimulating capacity of cholestatic plasma, and this signifies a change in sensitivity to endotoxin.

Serum cholesterol in cerebral malignancies

Reduced blood cholesterol levels were reported in patients with a variety of malignant peripheral tumors. This fact is likely related to increased cholesterol demand by proliferating tumor cells. The question arises whether this 'tumor-associated hypocholesterolemia' occurs also in patients with brain tumors, and--if it does not--whether its absence can be related to the location of the tumors. We have compared fasting serum total cholesterol levels among three groups of patients: 52 patients with gliomas, 56 patients with symptomatic metastatic brain tumors, and 50 patients harboring malignant tumors of peripheral location but showing no clinical signs of brain metastases. Patients in the last group, despite being--on an average--more age-advanced, had lower total serum cholesterol levels than either the patients with gliomas, or the patients with brain metastases. No difference in the cholesterol levels was found between the two latter groups, and a majority of these patients had borderline or elevated cholesterol levels. This apparent absence of 'tumor-associated hypocholesterolemia' in brain tumor patients may be related to either brain tumors' ability to synthesize cholesterol de novo and their reduced dependence on peripheral cholesterol supply, the existence of brain tumor-blood barrier, effect of medications used to counteract brain edema and seizures, or a combination of these factors.

Human recombinant apolipoprotein E-enriched liposomes can mimic low-density lipoproteins as carriers for the site-specific delivery of antitumor agents

Progressive hypocholesterolemia is a feature associated with a number of cancers of different origin, and it is caused by the high expression of low-density lipoprotein (LDL) receptors (LDLrs) on many tumor cell types. Selective delivery of chemotherapeutics using LDL as a carrier has therefore been proposed, but the endogenous nature of LDL hampers its pharmaceutical application. In the current study, we explored the possibility of synthesizing liposomes that mimic LDL from commercially available lipids and proteins. Small unilamellar liposomes were created (28.9 +/- 0.9 nm) and complexed with 5.8 +/- 0.7 molecules of human recombinant apolipoprotein E (apoE). On intravenous injection into rats, the liposomes retained their aqueous core, structural integrity, and the majority of the preassociated apoE. [3H]Cholesteryl oleate-labeled apoE-enriched liposomes showed a relatively long serum half-life (>5 hr), and a low uptake by cells of the reticuloendothelial system was observed (<0.8% of the injected dose at 30 min after injection). Pretreatment of rats with 17alpha-ethinyl estradiol, which induces the expression of the LDLr on the liver and adrenals, led to a 2.5-fold accelerated serum clearance (t1/2 = 123 +/- 10 min) and a selectively increased uptake of liposomes by the liver (2.0-fold) and adrenals (3.8-fold). The liver association of the liposomes was coupled to the lysosomal uptake route, similarly as for LDL. In vitro studies using B16 melanoma cells showed that the liposomes bound exclusively to the LDLr via their apoE moiety (90,000 liposomes/cell), with a 14-fold higher affinity (Kd = 0.77 +/- 0.09 nM) than LDL itself. Because of their favorable properties, we anticipate that these apoE-enriched liposomes are advantageous compared with native LDL in the development of a selective LDLr-targeted antitumor therapy.

Involvement of tyrosine kinase activity in the low-density lipoprotein receptor expression in human lung adenocarcinoma cell line A549

In common with other tumour cell lines but in contrast to normal cells, the human adenocarcinoma cell line A549 showed a biphasic regulation of the LDL receptor activity during growth both LDL binding and metabolism (sum of internalised and degraded LDL) increased during the log exponential growth phase and decreased when the cells approached confluence. This period of increasing LDL receptor activity coincided with a high resistance to cholesterol down-regulation which suggested a sterol-independent pathway of stimulation. Since A549 cells have an autocrine loop of growth factors, two of which have tyrosine kinase activity, the LDL receptor activity was tested in the presence of the tyrosine kinase inhibitor, genistein. When cells were incubated in the absence of cholesterol (LPDS medium), the inhibition that occurred was two-fold higher during the exponential growth phase than during the confluent phase. Moreover, the residual LDL binding and metabolism after genistein inhibition were completely resistant to down-regulation by cholesterol only during the growth phase. When cholesterol was present (FCS medium). inhibition was observed only during the growth phase. The inhibition of LDL receptor activity by genistein was found to be the result of a loss in the number of LDL binding sites, while the dissociation constant was not affected. This loss was accompanied by a disappearance of mRNA as shown by RNase mapping. By comparison, LDL receptor activity of normal cells (fibroblasts) was also affected by genistein during the exponential growth phase but was much more cholesterol-dependent. Taken together, these results suggest that the tyrosine kinase pathway is essential to up-regulate LDL receptor expression in highly dividing cells and particularly in tumour cells in which the sterol regulation is deficient.