Total serum cholesterol and cancer incidence in the Metabolic syndrome and Cancer Project (Me-Can)

The role of cholesterol metabolism in lung cancer

Elevated serum cholesterol metabolism is associated with a reduced risk of lung cancer. Disrupted cholesterol metabolism is evident in both lung cancer patients and tumor cells. Inhibiting tumor cell cholesterol uptake or biosynthesis pathways, through the modulation of receptors and enzymes such as liver X receptor and sterol-regulatory element binding protein 2, effectively restrains lung tumor growth. Similarly, promoting cholesterol excretion yields comparable effects. Cholesterol metabolites, including oxysterols and isoprenoids, play a crucial role in regulating cholesterol metabolism within tumor cells, consequently impacting cancer progression. In lung cancer patients, both the cholesterol levels in the tumor microenvironment and within tumor cells significantly influence cell growth, proliferation, and metastasis. The effects of cholesterol metabolism are further mediated by the reprogramming of immune cells such as T cells, B cells, macrophages, myeloid-derived suppressor cells, among others. Ongoing research is investigating drugs targeting cholesterol metabolism for clinical treatments. Statins, targeting the cholesterol biosynthesis pathway, are widely employed in lung cancer treatment, either as standalone agents or in combination with other drugs. Additionally, drugs focusing on cholesterol transportation have shown promise as effective therapies for lung cancer. In this review, we summarized current research regarding the rule of cholesterol metabolism and therapeutic advances in lung cancer.

The relationship between lipoproteins and the risk of esophageal cancer: a Mendelian randomization study

Backgrounds and aims

Esophageal cancer (EC) causes approximately 508,000 deaths annually, making it a significant cause of cancer-related mortality. While previous studies have suggested an association between lipoprotein levels and EC risk, the causal relationship remains unexplored. This study aims to investigate the causal link between lipoproteins and EC using Mendelian randomization (MR).

Methods and findings

This study employed MR to determine the causal effect between lipoproteins and EC risk, with body mass index (BMI) used as a confounder in multivariable MR (MVMR) analysis. Sensitivity analyses were conducted to assess the reliability of the results. Univariable MR (UVMR) analysis indicated that low-density lipoprotein (LDL) had a significant inverse association with EC risk (p = 0.03; OR = 0.89; 95%CI, 0.73-0.98), while high-density lipoprotein (HDL) and triglycerides showed no significant association. In the synthesis of findings across diverse datasets, LDL maintained a notable inverse association with the likelihood of EC (p < 0.001; OR = 0.89; 95%CI, 0.84-0.94). Triglyceride levels indicated a potential trend toward an adverse correlation with EC susceptibility (p = 0.03; OR = -0.94; 95%CI, 0.89-0.99), whereas HDL levels did not establish a definitive causal link with the occurrence of EC. MVMR analysis, adjusting for BMI, confirmed these findings.

Conclusion

LDL exhibits a clear inverse causal relationship with EC risk, regardless of BMI adjustment. No causal effects were observed for HDL in relation to EC risk. Meanwhile, there is a small but statistically significant causal relationship between triglycerides and EC risk.

Investigating the Relationship between Body Mass Index, Cholesterol, and Cancer in United States Adults: A Cross-Sectional Study

The purpose of this cross-sectional study was to investigate the relationship between Body Mass Index (BMI), cholesterol, and cancer in United States (US) adults. Data were collected from the 2020 Medical Expenditure Panel Survey (MEPS). Eligible participants were US adults (≥18 years) with data on BMI, cholesterol, and cancer status, who were alive at the end of the data collection period. An adjusted logistic regression model assessed associations between eight possible combinations of BMI and cholesterol status (independent variable) with cancer diagnosis (dependent variable). Among 27,805 individuals in the 2020 MEPS data, 20,818 met the eligibility criteria (weighted N = 252,340,615). Of these 2668 (weighted N = 29,770,359) had cancer and 18,150 (weighted N = 222,570,256) did not have cancer. In the adjusted logistic regression model, underweight and normal weight individuals with high cholesterol were associated with higher odds of cancer (odds ratio, OR = 2.002, and 95% confidence interval, CI = 1.032-3.885, and OR = 1.326 and 95% CI = 1.047-1.681, respectively), while obese individuals with normal cholesterol were associated with lower odds of cancer (OR = 0.681; 95% CI = 0.543-0.853) compared to normal weight individuals with normal cholesterol. This study offers insights into specific groups of individuals who may be prioritized for cancer prevention. Further research is required to investigate these findings in additional subpopulations.

Primary hypocholesterolemia is associated with an increased risk of hepatic complications in the general population

BACKGROUND & AIMS

Beyond cardiovascular disease protection, the health consequences of very low concentrations of low-density lipoprotein-cholesterol (LDL-C) remain a matter of debate. In primary hypobetalipoproteinemia (HBL), liver steatosis and cirrhosis have occasionally been reported. Here, we aimed to investigate the association between HBL and the risk of hepatic complications (cirrhosis complications and/or primary liver cancer) in the general population.

METHODS

A cohort study was conducted in the French population-based cohort CONSTANCES. Participants with primary HBL (LDL-C <5th percentile for age and sex, [HBL]) were compared with those with normal LDL-C concentrations (40th-60th percentile, [Control]). Participants on lipid-lowering therapies were excluded. For hepatic complications, follow-up events were compared by calculating the incidence density ratio (IDR). The same analyses were replicated in the UK Biobank (UKBB) cohort.

RESULTS

In the CONSTANCES and UKBB cohorts, 34,653 and 94,666 patients were analyzed, with median ages of 45 and 56 years, mean LDL-C concentrations (HBL vs. control) of 71 vs. 128 mg/dl and 86 vs. 142 mg/dl, and mean follow-up durations of 5.0 and 11.5 years, respectively. The HBL group presented a higher incidence of hepatic complications than the control group: 0.32/ vs. 0.07/1,000 person-years (IDR = 4.50, 95% CI 1.91-10.6) in CONSTANCES, and 0.69/ vs. 0.21/1,000 person-years (IDR = 3.27, 95% CI 2.63-4.06) in the UKBB. This risk proved to be independent of classic risk factors for liver disease (obesity, alcohol consumption, diabetes, viral hepatitis), including in a 5-year landmark analysis excluding early events. Sensitivity analyses based on apoliprotein-B levels (instead of LDL-C levels) or genetically defined HBL showed similar results.

CONCLUSIONS

HBL is associated with a markedly increased risk of hepatic complications. HBL must be considered as a substantial independent risk factor for liver diseases which justifies specific prevention and screening.

IMPACT AND IMPLICATIONS

Hypobetalipoproteinemia (HBL) is a lipid disorder characterized by permanent, inherited low levels (below the 5th percentile) of low-density lipoprotein-cholesterol. While HBL is associated with a lower risk of cardiovascular events, some studies suggest that it may be associated with a potential risk of hepatic steatosis and hepatic complications. Here, we studied the association between HBL and hepatic complications (defined as cirrhosis complications and/or primary liver cancer) in two populations of several hundred thousand people, both in France (CONSTANCES cohort) and the United Kingdom (UKBB). The results show that HBL is associated with a significant and independent excess risk of hepatic complications, including primary liver cancer. Thus, in people with HBL, the value of regular liver monitoring must be studied.

Diabetes and further risk of cancer: a nationwide population-based study

BACKGROUND

Individuals with diabetes have a significantly higher risk of developing various forms of cancer, and the potential biological links between these two diseases are not completely understood.

METHODS

This was a longitudinal retrospective nationwide cohort study, a study design that allows us to examine the natural course of cancer development over an extended period of time with a large sample size. Initially, 3,111,975 and 22,208,395 eligible patients aged ≥ 20 years with and without diabetes, respectively, were matched by age, sex, and the Charlson comorbidity index. Ultimately, 1,751,457 patients were selected from each group. Stratified populations for diabetic retinopathy (DR) (n = 380,822) and without DR (n = 380,822) as well as proliferative DR (PDR) (n = 141,150) and non-proliferative DR (NPDR) (n = 141,150) were analyzed in this study. The main outcome measure was the first-time diagnosis of cancer during the follow-up period.

RESULTS

We observed a 20% higher risk of total cancer incidence [hazard ratios (HR), 1.20; p < 0.001] in the diabetes cohort compared to the non-diabetes cohort. The highest HR was observed for liver and pancreas cancers. Moderately increased risks were observed for oral, colon, gallbladder, reproductive (female), kidney, and brain cancer. Furthermore, there was a borderline significantly increased risk of stomach, skin, soft tissue, female breast, and urinary tract (except kidney) cancers and lymphatic and hematopoietic malignancies. The stratified analysis revealed that the total cancer incidence was significantly higher in the DR cohort compared to the non-DR cohort (HR, 1.31; p < 0.001), and there was a borderline increased risk in the PDR cohort compared to the NPDR cohort (HR, 1.13; p = 0.001).

CONCLUSIONS

This study provides large-scale, nationwide, population-based evidence that diabetes is independently associated with an increased risk of subsequent development of total cancer and cancer at specific sites. Notably, this risk may further increase when DR develops.

Associations between "Cancer Risk", "Inflammation" and "Metabolic Syndrome": A Scoping Review

BACKGROUND

Individuals with metabolic syndrome exhibit simultaneously pro-thrombotic and pro-inflammatory conditions which more probably can lead to cardiovascular diseases progression, type 2 diabetes mellitus, and some types of cancer. The present scoping review is aimed at highlighting the association between cancer risk, inflammation, and metabolic syndrome.

METHODS

A search strategy was performed, mixing keywords and MeSH terms, such as "Cancer Risk", "Inflammation", "Metabolic Syndrome", "Oncogenesis", and "Oxidative Stress", and matching them through Boolean operators. A total of 20 manuscripts were screened for the present study. Among the selected papers, we identified some associations with breast cancer, colorectal cancer, esophageal adenocarcinoma, hepatocellular carcinoma (HCC), and cancer in general.

CONCLUSIONS

Cancer and its related progression may also depend also on a latent chronic inflammatory condition associated with other concomitant conditions, including type 2 diabetes mellitus, metabolic syndrome, and obesity. Therefore, prevention may potentially help individuals to protect themselves from cancer.

Association between insulin resistance, metabolic syndrome and its components and lung cancer: a systematic review and meta-analysis

BACKGROUND

A growing body of evidence points to the association between insulin resistance (IR), metabolic syndrome (MetS) and its components and lung cancer incidence, but remains controversial and unknown.

METHODS

A systematic search was conducted through PubMed, Embase, Cochrane Library, the China National Knowledge Infrastructure (CNKI) and Wanfang databases for the corresponding studies. Each study reported the risk estimate and 95% confidence intervals (CI) for lung cancer, and a fixed effects model or random effects model was used for outcome.

RESULTS

We included 31 publications involving 6,589,383 people with 62,246 cases of lung cancer. Diabetes mellitus (DM) (RR = 1.11, 95% CI  1.06-1.16, P = 0.000) and IR (RR = 2.35, 95% CI  1.55-3.58, P = 0.000) showed a positive association with lung cancer risk. BMI (RR = 0.66, 95% CI  0.54-0.81, P = 0.000) and HDL-C (RR = 0.88, 95% CI  0.79-0.97, P = 0.010) were negatively correlated with lung cancer. MetS(RR = 0.99, 95% CI  0.90-1.09, P = 0.801), TC (RR = 0.93, 95% CI  0.81-1.06, P = 0.274), TG (RR = 0.99, 95% CI  0.88-1.12,P = 0.884), LDL-C (RR = 1.01, 95% CI  0.87-1.16, P = 0.928), hypertension (RR = 1.01, 95% CI  0.88-1.15, P = 0.928), FBG (RR = 1.02, 95% CI  0.92-1.13, P = 0.677) and obesity (RR = 1.11, 95% CI  0.92-1.35, P = 0.280) were not associated with lung cancer.

CONCLUSION

Our study showed that the risk of lung cancer is correlated with DM, IR, BMI, and HDL-C. Timely control of these metabolic disorders may have a positive effect on preventing lung cancer. Trial registration Our study has been registered in the Prospective Register of Systematic Reviews (PROSPERO), ID: CRD42023390710.

Association of serum lipids and abnormal lipid score with cancer risk: a population-based prospective study

BACKGROUND

Serum lipid levels are associated with cancer risk. However, there still have uncertainties about the single and combined effects of low lipid levels on cancer risk.

METHODS

A prospective cohort study of 33,773 adults in Shanghai between 2016 and 2017 was conducted. Total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels were measured. Cox proportional hazard models were used to assess the association of single and combined lipids with overall, lung, colon, rectal, thyroid gland, stomach, and female breast cancers. The effect of the combination of abnormal lipid score and lifestyle on cancer was also estimated.

RESULTS

A total of 926 incident cancer cases were identified. In the RCS analysis, hazard ratios (HRs) of overall cancer for individuals with TC < 5.18 mmol/L or with LDL-C < 3.40 mmol/L were higher. Low TC was associated with higher colorectal cancer risk (HR [95% CI] = 1.76 [1.09-2.84]) and low HDL-C increased thyroid cancer risk by 90%. Abnormal lipid score was linearly and positively associated with cancer risk, and smokers with high abnormal lipid scores had a higher cancer risk, compared to non-smokers with low abnormal lipid scores (P < 0.05).

CONCLUSIONS

Low TC levels were associated with an increased risk of overall and colorectal cancer. More attention should be paid to participants with high abnormal lipid scores and unhealthy lifestyles who may have a higher risk of developing cancer. Determining the specific and comprehensive lipid combinations that affect tumorigenesis remains a valuable challenge.

Dietary fats and serum lipids in relation to the risk of ovarian cancer: a meta-analysis of observational studies

Although numerous epidemiological studies investigated the association between dietary fat intakes or serum lipid levels and ovarian cancer risk, a consistent and explicit conclusion for specific dietary fats or serum lipids that increase the risk of ovarian cancer is not available. In this study, a systematic review and meta-analysis were conducted to assess the key dietary fats and serum lipids that increased the risk of ovarian cancer. Databases such as PubMed, Web of Science, and EMBASE were searched for observational studies. A total of 41 studies met the inclusion criteria, including 18 cohort and 23 case-control studies (109,507 patients with ovarian cancer and 2,558,182 control/non-ovarian cancer participants). Higher dietary intakes of total fat (RR = 1.19, 95% CI = 1.06-1.33, I2 = 60.3%), cholesterol (RR = 1.14, 95% CI = 1.03-1.26, I2 = 19.4%), saturated fat (RR = 1.13, 95% CI = 1.04-1.22, I2 = 13.4%), and animal fat (RR = 1.21, 95% CI = 1.01-1.43, I2 = 70.5%) were significantly associated with a higher risk of ovarian cancer. A higher level of serum triglycerides was accompanied by a higher risk of ovarian cancer (RR = 1.33, 95% CI = 1.02-1.72, I2 = 89.3%). This meta-analysis indicated that a higher daily intake of total fat, saturated fat, animal fat, and cholesterol and higher levels of serum triglycerides were significantly associated with an increased risk of ovarian cancer.

Is cholesterol a risk factor for breast cancer incidence and outcome?

Cholesterol plays important roles in many physiological processes, including cell membrane structure and function, hormone synthesis, and the regulation of cellular homeostasis. The role of cholesterol in breast cancer is complex, and some studies have suggested that elevated cholesterol levels may be associated with an increased risk of developing breast cancer, while others have found no significant association. On the other hand, other studies have shown that, for total cholesterol and plasma HDL-associated cholesterol levels, there was inverse association with breast cancer risk. One possible mechanism by which cholesterol may contribute to breast cancer risk is as a key precursor of estrogen. Other potential mechanisms by which cholesterol may contribute to breast cancer risk include its role in inflammation and oxidative stress, which have been linked to cancer progression. Cholesterol has also been shown to play a role in signaling pathways regulating the growth and proliferation of cancer cells. In addition, recent studies have shown that cholesterol metabolism can generate tumor promoters such as cholesteryl esters, oncosterone, 27-hydroxycholesterol but also tumor suppressor metabolites such as dendrogenin A. This review summarizes some of the most important clinical studies that have evaluated the role of cholesterol or its derivatives in breast cancer. It also addresses the role of cholesterol and its derivatives at the cellular level.

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.

Association between metabolic syndrome, insulin resistance, and IGF-1 in breast cancer survivors of DIANA-5 study

PURPOSE

Circulating insulin-like growth factor-1 (IGF-1) is positively associated with the risk of BC recurrence, and is more frequently dysregulated in older people, especially in those with metabolic syndrome (MetS) and obesity. This study aimed to analyze the association between IGF-1 levels and indices of MetS and insulin resistance in BC survivors.

METHODS

Baseline data of 563 BC survivors enrolled in the DIet and ANdrogen-5 (DIANA-5; NCT05019989) study were analyzed.

RESULTS

Lower circulating IGF-1 levels in subjects with MetS than in those without MetS were found. After stratification of the patients according to the diagnosis of MetS, we highlighted that the insulin was the main predictor of elevated IGF-1 levels only in subjects without MetS. Moreover, we found an interaction between high-density lipoprotein cholesterol (HDL-C), glycemia, and IGF-1 levels, showing a positive correlation between HDL-C and IGF-1, especially in subjects with higher values of glycemia and without a diagnosis of MetS.

CONCLUSIONS

While IGF-1 levels appear to be much more impaired in subjects diagnosed with MetS, in non-MetS subjects, IGF-1 levels may respond better to metabolic parameters and lifestyle changes. Further studies are needed to analyze the role of physical activity and/or dietary intervention in modulating IGF-1 concentrations in BC survivors.

IMPLICATIONS FOR CANCER SURVIVORS

These results could have important clinical implications for planning customized strategies aimed at modulating IGF-1 levels in BC survivors. In fact, while the IGF-1 system seems to be much more compromised in subjects with a diagnosis of MetS, in noMetS subjects, IGF-1 levels could better respond to lifestyle changes.

Blood metabolic biomarkers and the risk of head and neck cancer: An epidemiological study in the Swedish AMORIS Cohort

Multiple studies have investigated the role of carbohydrate and lipid metabolism on the risk of head and neck cancer (HNC), with however conflicting results. We performed a study of 561,388 individuals of the Swedish AMORIS Cohort with blood test results on nine biomarkers for carbohydrate, lipid, and apolipoprotein metabolism during 1985-1996. We examined the associations of these biomarkers with the future risk of HNC through 2020 and demonstrated the temporal changes of these biomarkers during the decades before cancer diagnosis. We found that there was a positive association between blood level of glucose, total cholesterol (TC), triglycerides (TG), and Apoprotein A-I (ApoA-I) and the risk of HNC. Per standard deviation increase, the hazard ratio (HR) was 1.05 (95% confidence interval [CI] 1.02-1.09) for glucose, 1.09 (95% CI 1.05-1.13) for TC, 1.13 (95% CI 1.08-1.17) for TG, and 1.11 (95% CI 1.04-1.19) for ApoA-I. The associations were primarily noted for squamous cell carcinoma but not adenocarcinoma. Compared to controls, patients with HNC, primarily squamous cell carcinoma, showed constantly higher levels of glucose, TC, TG, and ApoA-I during the 30 years before diagnosis. In conclusion, findings of the study add new and high-quality evidence to the early involvement of carbohydrate and lipid metabolism in the oncogenesis of human cancer.

Exploration of Risk Factors for Pancreatic Cancer and Development of a Clinical High-Risk Group Rating Scale

(1) Background: There are few studies on people at high risk for clinical pancreatic cancer (PC). We aimed to explore the risk factors of PC and establish a scale for identifying high-risk populations of clinical PC. (2) Methods: We conducted a matched case-control study, retrospectively collecting demographic data and common clinical indicators from all subjects. Logistic regression was used to explore the risk factors of PC. Based on these factors, we created a high-risk population rating scale, which showed a higher diagnostic value. (3) Results: 385 cases and 428 controls were finally enrolled in our study. Multivariate analysis showed that body mass index (BMI) below 18.5 kg/m2 (OR 5.944, 95%CI: 1.759~20.084), smoking (OR 2.745, 95%CI: 1.555~4.844), new-onset diabetes (OR 5.239, 95%CI: 2.091~13.125), low high-density lipoprotein cholesterol (HDL-C) levels (OR 1.790, 95%CI: 1.044~3.069), and carbohydrate antigen 19-9 (CA19-9) levels no less than 35 U/mL (OR 160.328, 95%CI: 83.392~308.243) were associated with an increased risk of PC, whereas high total cholesterol (TC) levels were related to a lower risk of PC (OR 0.392, 95%CI: 0.211~0.730). The high-risk population scale, whose area under the receiver operating curve reached 0.948 (p < 0.001), showed a greater clinical diagnostic value. (4) Conclusions: Smoking history, new-onset diabetes, BMI, TC, HDL-C, and CA19-9 levels were associated with the risk of PC. The high-risk population rating scale might be used for early clinical PC screening.

Serum cholesterol and the risk of developing hormonally driven cancers: A narrative review

Although cholesterol has been hypothesized to promote cancer development through several potential pathways, its role in the risk of developing hormonally driven cancer is controversial. This literature review summarizes evidence from the highest quality studies to examine the consistency and strength of the relationship between serum cholesterol parameters and incidence of hormonally driven cancer. Articles were identified using EMBASE. Longitudinal observational studies published between January 2000 and December 2020 were considered for inclusion. The endpoint of interest was incident prostate, ovary, breast, endometrium, and uterine cancers. In total, 2732 reports were identified and screened; 41 studies were included in the review. No associations were found for ovarian cancer. Most endometrial cancer studies were null. The majority (76.9%) of studies reported no association between cholesterol and prostate cancer. Data on breast cancer were conflicting, associations limited, and effect sizes modest. Our results do not provide evidence for a clear association between cholesterol and different types of incident, hormonally driven reproductive cancers. Future studies should investigate the impact of lipid-lowering therapy.

An Updated Systematic Review and Meta-Analysis on Association of Serum Lipid Profile With Risk of Breast Cancer Incidence

Background

This meta-analysis was performed to investigate the effect of serum lipids on the risk of breast cancer incidence.

Methods

PubMed, Web of Science, Scopus, and EMBASE were searched systematically from January 1998 to April 2019. Inclusion criteria were English observational studies (cohort or case-control) and the concentration of at least one of the lipid profile components (total cholesterol/triglycerides/low-density lipoprotein cholesterol/high-density lipoprotein cholesterol) measured before a diagnosis of breast cancer (BC). The studies were included in which the relative risk (RR) had been reported with 95% confidence intervals (CIs). A random-effects model was used.

Results

A total of 25 studies were found, including 2,882,789 participants in cohort studies with 45,481 cases with BC, and 1983 BC cases and 2963 case-control studies. Combined RR of cohort studies for the highest versus lowest for the BC was LDL-C: 0.95 (95% CI: 0.89-1.01), triglycerides (TG): 0.95 (95% CI: 0.91-0.99; P = 0.02), total cholesterol (TC): 0.98 (95% CI: 0.91-1.05), and HDL-C: 0.86 (95% CI: 0.63-1.18). Combined RR of case-control studies for the highest versus lowest was LDL-C: 1.08 (95% CI: 0.78-1.48), TG: 1.73 (95% CI: 0.94-3.18), TC: 1.02 (95% CI: 0.80-1.29), and HDL-C: 0.79 (95% CI: 0.65-0.97).

Conclusions

Based on the results, it can be concluded that only TG but not TC and/or LDL-C had a significant inverse association with the risk of BC incidence. HDL-C showed a significant protective effect against breast cancer in postmenopausal women and case-control studies.

Temporal Association of Total Serum Cholesterol and Pancreatic Cancer Incidence

Previous studies have suggested a “cholesterol-lowering effect” of preclinical pancreatic cancer, suggesting lower total cholesterol as a potential diagnostic marker. Leveraging repeated measurements of total cholesterol, this study aims to examine the temporal association of total cholesterol and pancreatic cancer incidence. We conducted a nested case-control study based on a Korean National Health Insurance Service−Health Screening Cohort, including 215 pancreatic cancer cases and 645 controls matched on age and sex. Conditional logistic regression was applied to estimate the odds ratio (OR) and 95% confidence interval (CI) for the associations of pancreatic cancer incidence with total cholesterol levels across different time windows over 11 years before pancreatic cancer diagnosis (recent, mid, distant). We found that, compared to participants with total cholesterol < 200 mg/dL in the recent 3 years prior to diagnosis, those having total cholesterol ≥ 240 mg/dL showed a significantly lower pancreatic cancer incidence (OR = 0.50 (0.27−0.93)). No significant association was found in relation to total cholesterol measured in the mid and distant past. When changes in total cholesterol over the three time periods were analyzed, compared with those with total cholesterol levels consistently below 240 mg/dL over the entire period, the OR of pancreatic cancer was 0.45 (0.20−1.03) for participants with recent-onset hypercholesterolemia, 1.89 (0.95−3.75) for recent-resolved hypercholesterolemia, and 0.71 (0.30−1.66) for consistent hypercholesterolemia. In conclusion, while high total cholesterol in the recent past may indicate a lower pancreatic cancer incidence, a recent decrease in total cholesterol may suggest an elevated incidence of pancreatic cancer.

Effect of Serum Lipid Profile on the Risk of Breast Cancer: Systematic Review and Meta-Analysis of 1,628,871 Women

Dyslipidemia has been linked to breast cancer incidence. The aim of the present meta-analysis was to further investigate the relationship between the serum lipid profile and breast cancer risk. Databases such as PubMed, EMBASE, and Web of Sciences were searched up to the end of January 2021 using certain MeSH and non-MeSH keywords and combinations to extract related published articles. Twenty-six prospective studies involving 1,628,871 women, of whom 36,590 were diagnosed with breast cancer during the follow-up period met the inclusion criteria. A negative and significant association was found between the HDL-C level and the risk of breast cancer (relative risk (RR): 0.85, 95% CI: 0.72–0.99, I²: 67.6%, p = 0.04). In contrast, TG (RR: 1.02, 95% CI: 0.91–1.13, I²: 54.2%, p = 0.79), total cholesterol (TC) (RR: 0.98, 95% CI: 0.90–1.06, I²: 67.2%, p = 0.57), apolipoprotein A (ApoA) (RR: 0.96, 95% CI: 0.70–1.30, I²: 83.5%, p = 0.78) and LDL-C (RR: 0.93, 95% CI: 0.79–1.09, I²: 0%, p = 0.386) were not associated with breast cancer development. In studies adjusting for hormone use and physical activity, breast cancer risk was positively correlated with TC (RR: 1.05, 95% CI: 1.01–1.10). Similarly, TG was significantly related to breast cancer development after adjustment for baseline lipids (RR: 0.92, 95% CI: 0.85–0.99) and race (any races mentioned in each study) (RR: 1.80, 95% CI: 1.22–2.65). In the present meta-analysis, HDL-C was inversely related to breast cancer risk. Overall, data on the links between lipids and breast cancer are conflicting. However, there is increasing evidence that low HDL-C is related to an increased risk for this type of malignancy.

The Association between Hypertriglyceridemia and Colorectal Cancer: A Long-Term Community Cohort Study in Taiwan

(1) Background: Colorectal cancer (CRC) is the third most common malignancy and the second leading cause of cancer deaths worldwide. It often diagnosed at advanced stages, and with increasing incidence at younger generation. CRC poses a heavy financial burden and a huge public health challenge nowadays. Lipoproteins and serum lipids may have an influence on carcinogenesis by making oxidative stress, inflammation, and insulin resistance. Dyslipidemia plays a potential role in the risk of CRC. The purpose of this study is to use nationally representative samples to determine epidemiologic characteristics of CRC in the Taiwanese population, and to evaluate the associations between baseline levels of lipid profile and their effect on risk of colorectal cancer (CRC) comprehensively and quantitatively. The control of dyslipidemia in primary and secondary prevention may reduce the disease burden of CRC. (2) Methods: This is a nationwide long-term community-based prospective cohort study. Data were retrieved from the nationwide population-based Taiwanese Survey on Hypertension, Hyperglycemia and Hyperlipidemia (TwSHHH). Variables were estimated by the Cox proportional hazards model which was then further adjusted for age. We also calculated the relative ratios (RRs) of CRC for joint categories of serum cholesterol, triglyceride (TG), low-density lipoproteins cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) level, and to examine their combined effect and statistical interactions. (3) Results: Male, age, waist circumference, diabetes mellitus (DM), high TG, high cholesterol level, smoking history, and metabolic syndrome were proved to increase the risk of CRC. In addition, DM patients with a TG level ≥150 mg/dL and cholesterol ≥180 mg/dL had a 4.118-fold higher risk of CRC as compared with a TG level <150 mg/dL and cholesterol level <180 mg/dL, which was a significant difference (95% CI, 1.061−15.975; p = 0.0407). (4) Conclusions: Patients with DM should control TG and cholesterol level through diet, exercise, or taking medications more aggressively, not only for preventing cardiovascular disease, but also for first prevention of CRC. The study can be valuable for the clinicians and policy makers to implement more precisely goals about dyslipidemia management.

Relationship between serum lipid level and colorectal cancer: a systemic review and meta-analysis

OBJECTIVE

Investigative studies report contradictory results of the relationship between serum lipid levels and the risk of colorectal cancer (CRC). We conducted a meta-analysis of prospective published studies to clarify the relationship between serum lipid and CRC risk.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed and Embase from inception until December 2020.

ELIGIBILITY CRITERIA

We considered prospective cohort and case-control studies that evaluated differences in serum lipid levels with the risk of developing CRC.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers screened and included the studies using standardised electronic data extraction forms. The relative risks of the studies were combined with random-effect and fixed-effect models and were analysed for heterogeneity, publication bias and sensitivity.

RESULTS

Twenty-four prospective studies, including 4 224 317 individuals with 29 499 CRC cases, were included in the meta-analysis. The total pooled risk ratio (RR) for high vs low concentrations of triglyceride (TG) concentrations was reported at 1.21 (95% CI 1.09 to 1.34; I²=46.8%), total cholesterol (TC) was at 1.15 (95% CI 1.08 to 1.22; I²=36.8%), high-density lipoprotein cholesterol (HDL-C) was 0.86 (95% CI 0.77 to 0.97; I²=28.8%) and low-density lipoprotein cholesterol (LDL-C) was observed at 1.03 (95% CI 0.75 to 1.41; I²=69.4%).

CONCLUSIONS

This meta-analysis shows that high levels of serum TG and TC are positively correlated with the incidence rate of CRC, while high levels of serum HDL-C are negatively correlated with CRC incidence rate. Furthermore, no association was found between LDL-C and the risk of developing CRC. Nevertheless, the heterogeneity brought about by comparative methods, demographic differences and pathological differences between the research subjects limits the effectiveness of the overall pooled results.

Obesity and Pancreatic Cancer: Recent Progress in Epidemiology, Mechanisms and Bariatric Surgery

More than 30% of people in the United States (US) are classified as obese, and over 50% are considered significantly overweight. Importantly, obesity is a risk factor not only for the development of metabolic syndrome but also for many cancers, including pancreatic ductal adenocarcinoma (PDAC). PDAC is the third leading cause of cancer-related death, and 5-year survival of PDAC remains around 9% in the U.S. Obesity is a known risk factor for PDAC. Metabolic control and bariatric surgery, which is an effective treatment for severe obesity and allows massive weight loss, have been shown to reduce the risk of PDAC. It is therefore clear that elucidating the connection between obesity and PDAC is important for the identification of a novel marker and/or intervention point for obesity-related PDAC risk. In this review, we discussed recent progress in obesity-related PDAC in epidemiology, mechanisms, and potential cancer prevention effects of interventions, including bariatric surgery with preclinical and clinical studies.

The Role of Circulating Protein and Metabolite Biomarkers in the Development of Pancreatic Ductal Adenocarcinoma (PDAC): A Systematic Review and Meta-analysis

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis, and this is attributed to it being diagnosed at an advanced stage. Understanding the pathways involved in initial development may improve early detection strategies. This systematic review assessed the association between circulating protein and metabolite biomarkers and PDAC development.

METHODS

A literature search until August 2020 in MEDLINE, EMBASE, and Web of Science was performed. Studies were included if they assessed circulating blood, urine, or salivary biomarkers and their association with PDAC risk. Quality was assessed using the Newcastle-Ottawa scale for cohort studies. Random-effects meta-analyses were used to calculate pooled relative risk.

RESULTS

A total of 65 studies were included. Higher levels of glucose were found to be positively associated with risk of developing PDAC [n = 4 studies; pooled relative risk (RR): 1.61; 95% CI: 1.16-2.22]. Additionally, an inverse association was seen with pyridoxal 5'-phosphate (PLP) levels (n = 4 studies; RR: 0.62; 95% CI: 0.44-0.87). Meta-analyses showed no association between levels of C-peptide, members of the insulin growth factor signaling pathway, C-reactive protein, adiponectin, 25-hydroxyvitamin D, and folate/homocysteine and PDAC risk. Four individual studies also reported a suggestive positive association of branched-chain amino acids with PDAC risk, but due to differences in measures reported, a meta-analysis could not be performed.

CONCLUSIONS

Our pooled analysis demonstrates that higher serum glucose levels and lower levels of PLP are associated with risk of PDAC.

IMPACT

Glucose and PLP levels are associated with PDAC risk. More prospective studies are required to identify biomarkers for early detection.

Serum lipid trajectories in the years before a lymphoma diagnosis

We conducted a case-control study of patients from the Clinical Practice Research Datalink in the United Kingdom to describe the trajectories of serum lipid in the years before a diagnosis of lymphoma. Study participants had at least one cholesterol measurement. Multilevel, multivariable linear longitudinal models were fit to examine the adjusted trajectories of serum lipid levels in the years before lymphoma diagnosis. Overall, 11,969 cases of non-Hodgkin lymphoma, 473 of Hodgkin lymphoma, and 61,894 controls were selected. Mean cholesterol levels in the years before the index date showed a more pronounced decrease in the 4 years before lymphoma diagnosis than in controls. Triglycerides levels were unrelated to case status. This research is the first to replicate the results of a similar study conducted in the United States while adjusting for more potential confounders. The newly described different behavior of cholesterol and triglycerides suggests a potential role of cholesterol in lymphomagenesis.

Increased risk of bladder cancer in young adult men with hyperlipidemia: A population-based cohort study

A high-cholesterol diet increases the risk of bladder cancer. The purpose of this nationwide longitudinal population-based retrospective cohort study is to investigate whether hyperlipidemia is a risk factor for bladder cancer.Data from Taiwan National Health Insurance Database were analyzed. The primary study end point was the occurrence of newly diagnosed bladder cancer. The relative risk of bladder cancer in a hyperlipidemia cohort was compared with that in an age- and gender-matched non-hyperlipidemia cohort by using the Cox proportional hazards regression model. Cox regression analyses were further adjusted by the propensity score.Our data revealed that the hyperlipidemia cohort (n = 33,555) had a significantly higher subsequent risk of bladder cancer than did the non-hyperlipidemia cohort (n = 33,555) (adjusted hazard ratio [HR] = 1.37, P = .005) after propensity score adjustment. Subgroup analyses revealed that men in the hyperlipidemia cohort had a significantly higher subsequent risk of bladder cancer than did those in the non-hyperlipidemia cohort (adjusted HR = 1.36, P = .040). However, the risk of bladder cancer was not significantly different between women in the hyperlipidemia cohort and those in the non-hyperlipidemia cohort. Subgroup analyses further revealed that the risk of bladder cancer was significantly higher in men aged 20 to 39 years in the hyperlipidemia cohort than in those in the non-hyperlipidemia cohort (adjusted HR = 5.45, P = .029).In conclusion, hyperlipidemia is a risk factor for bladder cancer in young adult men.

Association between serum lipids and breast cancer risk in premenopausal women: systematic review and meta-analysis

Objective

Associations between serum lipids and their individual components with premenopausal breast cancer risk are unclear. This meta-analysis summarized the literature on serum lipids and premenopausal breast cancer risk to elucidate their relationship.

Methods

Eligible studies were identified by searching the PubMed, Embase, China National Knowledge Infrastructure, and Wanfang databases until 31 December 2020. Standardized mean difference (SMD) scores with 95% confidence intervals (95%CIs) were used to assess the impact of serum lipids on premenopausal breast cancer risk. The I² statistic was calculated to measure the percentage of heterogeneity, and Egger’s test was performed to measure publication bias.

Results

Thirteen studies were included. The SMD scores of triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) were 12.90 (95%CI: 7.19–18.61) and 31.43 (95%CI: 8.72–54.15), respectively. The SMD scores of total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) were not significantly different between the groups. The included studies were highly heterogeneous. There were no publication biases found in TC, LDL-C, or HDL-C analyses, whereas publication bias was present in the TG analysis.

Conclusions

TG and LDL-C were higher in premenopausal breast cancer patients than in women without breast cancer. However, no significant differences were found in TC or HDL-C levels.

Association of metabolic traits with occurrence of nonalcoholic fatty liver disease-related hepatocellular carcinoma: A systematic review and meta-analysis of longitudinal cohort studies

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) has become one of the leading etiologies of hepatocellular carcinoma (HCC), but risk factors for NAFLD-related HCC occurrence have not been defined. NAFLD is often complicated by metabolic abnormalities, and there is a bidirectional association of metabolic abnormalities with NAFLD progression. This study aimed to systematically evaluate the relationship between metabolic traits and HCC occurrence in patients with NAFLD.

METHOD

This study reviewed eight eligible studies that included 297,956 participants, to determine the relationship between metabolic traits and the occurrence of HCC in patients with NAFLD.

RESULTS

Presence of diabetes mellitus (DM) was associated with increased risk of HCC (HR: 2.65, 95%CI: 2.02 ~ 3.49, P_{heterogeneity} = 0.589, I² = 0.0%). Stratified analysis revealed that this risk was higher in NAFLD patients with advanced fibrosis/cirrhosis (HR: 4.55, 95%CI: 2.34 ~ 8.87, P_{heterogeneity} = 0.870, I² = 0.0%). Nonetheless even in patients without cirrhosis, DM remained a high risk factor for HCC incidence (HR: 1.80, 95%CI: 1.05 ~ 3.06, P_{heterogeneity} = 0.291, I² = 10.4%). Overweight/obesity had a slight correlation with increased risk of HCC occurrence in NAFLD patients (HR: 1.31, 95%CI: 1.00 ~ 1.71, P_{heterogeneity} = 0.888, I² = 0.0%), while presence of hypertension and dyslipidemia had no correlation.

CONCLUSION

DM and overweight/obesity are high risk factors for NAFLD-related HCC. In particular, DM increases 4-fold the risk of HCC incidence in NAFLD patients with advanced fibrosis/cirrhosis. There is a need to strengthen surveillance for HCC in NAFLD patients with DM, especially in those with advanced fibrosis/cirrhosis.

Antihypertensive drugs and the risks of cancer: More fakes than facts

In the last century, the diffusion of medical news to the public has been profoundly changed by the progressive spread of more pervasive, but at the same time often unreliable, means of communication. The misinterpretation of scientific evidence or fallacious presentation through social media could play as a great drawback to the success in the management of many diseases. This may become particularly alarming when concerning chronic diseases widely affecting the population. Arterial hypertension is still today one of the major causes of mortality and morbidity in most countries, and its management generally requires chronic therapy lasting for decades. Therefore, a recent debate about the potential oncogenic effect of antihypertensive drugs has been made widely available to patients mostly through social media. Since this is a topic of great impact for millions of patients and of main relevance for the scientific community, it must not be contaminated by the spread of fake or twisted news. The objective of this article is to briefly discuss the almost complete lack of hard evidence about the potential oncogenic effect of the major classes of antihypertensive drugs as opposed to the exaggerated mediatic communication and impact of scattered and unconfirmed observations. We believe that it is of key importance to provide authoritative support for patients and clinicians from scientific societies and guidelines to balance an unopposed widespread penetration of twisted or even fake news.

Lipid biomarkers and Cancer risk - a population-based prospective cohort study in Taiwan

Background

Blood lipids are essential components for cellular growth. An inverse association between serum lipid levels and risk of cancer has led to a controversy among previous studies. The aim of this prospective cohort study was to investigate the association between blood lipids change and risk of cancer incidence.

Methods

A cohort of 4130 Taiwanese adults from the Taiwanese Survey on the Prevalence of Hypertension, Hyperglycemia, and Hyperlipidemia database underwent repeated examinations in 2002 and 2007. Six groups were established based on the combined baseline (lower/higher) and interval change (decreasing/stable/increasing) in plasma lipid levels. Multivariable Cox proportional hazard model was used to investigate the relationship between lipids change and all-cause cancer incidence.

Results

Two hundred and forty cancer events developed over a median follow-up of 13.4 years. Comparing these with individuals with decreasing lower-baseline lipid levels, cancer risk reduction was demonstrated in those with increasing lower-baseline total cholesterol (adjusted hazard ratio [aHR], 0.48; 95% confidence interval [CI], 0.27 to 0.85), low-density lipoprotein cholesterol (LDL-C; aHR, 0.56; 95% CI, 0.35 to 0.92), and non–high-density lipoprotein cholesterol (non-HDL-C) (aHR, 0.54; 95% CI, 0.31 to 0.92) levels. A decreased risk for cancer incidence also presented in participants with stable lower-baseline, decreasing and increasing higher-baseline LDL-C levels, and with decreasing and stable higher-baseline non-HDL-C levels.

Conclusions

The interval decline in lower-baseline total cholesterol, LDL-C, and non-HDL-C levels was linked to a higher risk for all-cause cancer incidence. More attention to a potential cancer risk may be warranted for an unexplained fall in serum lipids.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01570-1.

Cancer mortality in a population-based cohort of American Indians - The strong heart study

BACKGROUND

Cancer mortality among American Indian (AI) people varies widely, but factors associated with cancer mortality are infrequently assessed.

METHODS

Cancer deaths were identified from death certificate data for 3516 participants of the Strong Heart Study, a population-based cohort study of AI adults ages 45-74 years in Arizona, Oklahoma, and North and South Dakota. Cancer mortality was calculated by age, sex and region. Cox proportional hazards model was used to assess independent associations between baseline factors in 1989 and cancer death by 2010.

RESULTS

After a median follow-up of 15.3 years, the cancer death rate per 1000 person-years was 6.33 (95 % CI 5.67-7.04). Cancer mortality was highest among men in North/South Dakota (8.18; 95 % CI 6.46-10.23) and lowest among women in Arizona (4.57; 95 % CI 2.87-6.92). Factors independently associated with increased cancer mortality included age, current or former smoking, waist circumference, albuminuria, urinary cadmium, and prior cancer history. Factors associated with decreased cancer mortality included Oklahoma compared to Dakota residence, higher body mass index and total cholesterol. Sex was not associated with cancer mortality. Lung cancer was the leading cause of cancer mortality overall (1.56/1000 person-years), but no lung cancer deaths occurred among Arizona participants. Mortality from unspecified cancer was relatively high (0.48/100 person-years; 95 % CI 0.32-0.71).

CONCLUSIONS

Regional variation in AI cancer mortality persisted despite adjustment for individual risk factors. Mortality from unspecified cancer was high. Better understanding of regional differences in cancer mortality, and better classification of cancer deaths, will help healthcare programs address cancer in AI communities.

Association of Serum Anti-PCSK9 Antibody Levels with Favorable Postoperative Prognosis in Esophageal Cancer

Background

Esophageal cancer often appears as postoperative metastasis or recurrence after radical surgery. Although we had previously reported that serum programmed cell death ligand 1 (PD-L1) level correlated with the prognosis of esophageal cancer, further novel biomarkers are required for more precise prediction of the prognosis. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is associated with the cholesterol metabolism. But there was no report of relationship between serum PCSK9 antibody and cancer. Therefore, we investigated whether anti-PCSK9 antibodies could be a novel biomarker for solid cancer.

Methods

Serum levels of anti-PCSK9 antibodies and antigens in patients with solid cancer were analyzed using amplified luminescence proximity homogeneous assay-linked immunosorbent assay (AlphaLISA). The reactivity of serum antibodies against recombinant PCSK9 protein was investigated by Western blotting, and the expression of PCSK9 antigens in esophageal cancer tissues was examined by immunohistochemical staining.

Results

AlphaLISA showed that serum anti-PCSK9 antibody (s-PCSK9-Ab) levels were significantly higher in patients with esophageal cancer, gastric cancer, colorectal cancer, lung cancer, and breast cancer than in healthy donors, and patients with esophageal cancer had the highest levels. The presence of serum antibody in patients was confirmed by Western blotting. There was no apparent correlation between s-PCSK9-Ab and PCSK9 antigen levels. Immunohistochemical staining demonstrated the expression of PCSK9 antigen in both the cytoplasm and nuclear compartments of esophageal squamous cell carcinoma tissue but not in normal tissue. Compared with patients with low s-PCSK9-Ab levels, those with high s-PCSK9-Ab levels had a favorable postoperative prognosis after radical surgery for esophageal cancer. In the multivariate analysis, tumor depth and s-PCSK9-Ab level were identified as independent prognostic factors. In the univariate analysis of clinicopathological features, high PCSK9 antibody levels were not associated with sex, age, location, tumor depth, lymph node status, squamous cell carcinoma antigen, or p53-Ab, whereas they correlated significantly with PD-L1 levels, which were associated with unfavorable prognosis. Correlation between s-PCSK9-Ab and PD-L1 levels was also confirmed in the logistic regression analysis; therefore, low s-PCSK9-Ab levels could discriminate another poor prognosis group other than high-PD-L1 group.

Conclusions

Patients with solid cancer had higher s-PCSK9-Ab levels than healthy donors. High s-PCSK9-Ab levels indicated better prognosis for overall survival after surgery in patients with esophageal cancer.

In-silico HMG-CoA reductase-inhibitory and in-vivo anti-lipidaemic/anticancer effects of carotenoids from Spondias mombin

OBJECTIVES

Inhibition of HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase, the rate rate-determining enzyme for the biogenesis of cholesterol is known to show antineoplastic effects. Therefore, this study investigates the in-silico HMG-CoA reductase (HMGCR)-inhibitory and in-vivo anti-lipidaemic/anticancer effects of carotenoids from Spondias mombin.

METHODS

Carotenoids from S. mombin leaves were characterized with the aid of liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). The characterized phytochemicals were obtained from PubChem. They were docked into the orthosteric site of human HMGCR (Protein Data Bank code 1HW8) using AutoDock 4.0 suites. DMBA (7,12-dimethylbenz[a]anthracene) model of breast cancer was treated with the carotenoids extract from S. mombin (100 mg/kg and 200 mg/kg doses) to assess its anti-lipidaemic cum anticancer effects.

KEY FINDINGS

Carotenoids from S. mombin; beta-carotene-15,15'-epoxide, astaxanthin and 7,7',8,8'-tetrahydro-β-β-carotene demonstrate HMGCR inhibition. They form hydrophobic interactions with key residues within the catalytic domain of HMGCR. The carotenoids extract exhibits anti-lipidaemic/anticancer effects, lowering serum triglyceride, LDL and cholesterol concentration. It increases HDL concentration and downregulates the expression of HMGR, AFP, CEACAM-3, BRCA-1 and HIF-1 mRNAs.

CONCLUSION

Carotenoids from S. mombin demonstrate HMG-CoA reductase (HMGCR) inhibition, anti-lipidaemic, and anticancer effects. The inhibition of HMGCR by the carotenoids extract further poses it as a potential anti-hypercholesterolaemia compounds.

Assessing Presenting Symptoms, Co-Morbidities, and Risk Factors for Mortality in Underserved Patients With Non-Hereditary Early-Onset Colorectal Cancer

Background The presenting symptoms and co-morbidities contributing to mortality in young patients (age < 50 years old) with colorectal cancer (CRC) are poorly understood. We reviewed these features in our patient population with non-hereditary early-onset CRC (EO-CRC). Study aim This study aimed to assess characteristics of patients with a diagnosis of non-hereditary EO-CRC, including presenting symptoms and metabolic disorders contributing to mortality in underserved areas of southwest Virginia. Methods In this retrospective observational study, we selected patients aged 18-50 years with a diagnosis of non-hereditary EO-CRC from 2008 to 2016 at Carilion Roanoke Memorial Hospital. The electronic medical record was queried to identify demographic data, medical history, histopathology results, lab values, and mortality. The cumulative risks of symptoms and co-morbid metabolic disorders was estimated using Kaplan-Meier curves. Results We identified 139 patients with non-hereditary EO-CRC (mean age 41.6 ± 6.9 years). Almost half of these patients were obese (BMI > 30), 30.9% had a diagnosis of hypertension, 29% had hyperlipidemia (HLD), and 17.35% had diabetes mellitus type 2 (DM2). Diagnosis was delayed by 4.5 months from initial presentation, and 17% had advanced disease (stage III/IV). Also, 68.5% of patients were symptomatic with one to three symptoms, most commonly with rectal bleeding (45.3%). The chronicity of HLD (≥5 years) was associated with reduced survival in our patients with EO-CRC. The survival of females with multiple metabolic disorders was reduced compared to females with a single metabolic disorder. Conclusions Multiple symptoms, chronic HLD, and female gender with multiple metabolic disorders were factors associated with poor outcomes in non-hereditary EO-CRC patients.

NMR-Based Lipid Metabolite Profiles to Predict Outcomes in Patients Undergoing Interventional Therapy for a Hepatocellular Carcinoma (HCC): A Substudy of the SORAMIC Trial

Simple Summary

A hepatocellular carcinoma (HCC) is the most common cause of death in patients suffering from chronic liver diseases. In order to improve the prediction of outcomes in HCC patients, there is a need for new biomarkers. This pilot study aimed at identifying serum metabolites for the prediction of outcomes of HCC patients using nuclear magnetic resonance (NMR) spectroscopy. This analysis revealed that high serum concentrations of myo-inositol or dimethylamine were associated with an improved overall survival. In contrast, high concentrations of total cholesterol, LDL-cholesterol and LDL particles (LDL-P) were associated with a decreased overall survival. The identification of novel biomarkers using this NMR-based technology holds promise for opening new directions in the conduction of interventional trials in HCCs.

Abstract

Background: This exploratory study aimed to evaluate lipidomic and metabolomic profiles in patients with early and advanced HCCs and to investigate whether certain metabolic parameters may predict the overall survival in these patients. Methods: A total of 60 patients from the prospective, randomized-controlled, multicenter phase II SORAMIC trial were included in this substudy; among them were 30 patients with an early HCC who underwent radiofrequency ablation combined with sorafenib or a placebo and 30 patients with an advanced HCC who were treated with a selective internal radiation therapy (SIRT) plus sorafenib vs. sorafenib alone. The blood serum of these patients was analyzed using a standardized nuclear magnetic resonance (NMR) platform. All tested metabolites were correlated with the overall survival. Results: The overall survival (OS) was significantly higher in patients with an early HCC (median OS: 34.0 months) compared with patients with an advanced HCC (median OS: 12.0 months) (p < 0.0001). Patients with high serum concentrations of myo-inositol (MI) had a higher overall survival compared with patients with low concentrations (21.6 vs. 13.8 months) with a Pearson correlation coefficient of 0.331 (p = 0.011). Patients with high serum concentrations of dimethylamine had a higher overall survival compared with patients with low concentrations (25.1 vs. 19.7 months) with a Pearson correlation coefficient of 0.279 (p = 0.034). High concentrations of total cholesterol, LDL-cholesterol and LDL particles (LDL-P) were associated with a decreased overall survival. Conclusions: NMR-based lipidomic and metabolomic profiling has the potential to identify individual metabolite biomarkers that predict the outcome of patients with an HCC exposed to non-invasive therapeutic management.

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.

Early age onset colorectal cancer

The incidence and mortality associated with colorectal cancer (CRC) diagnosed in patients under the age of 50 have been steadily increasing. The exact etiology of these epidemiologic trends is unclear. This chapter will provide a comprehensive review on the topic of early age onset colorectal cancer (EAO-CRC), defined as colorectal cancer (CRC) diagnosed in patients under the age of 50. Topics reviewed will include the epidemiology of EAO-CRC around the world, clinical and pathological features of EAO-CRC in contrast to later age onset CRC (CRC diagnosed on those over the age of 50) and the observed molecular and somatic characteristics. This chapter will review the etiologies to EAO-CRC and the established, as well as proposed risk factors for disease. Evidence-based approaches to prevention, early detection, treatment and survivorship will be presented.

Antihypertensive drugs and the risk of cancer: a critical review of available evidence and perspective

: The issue of a potential danger of antihypertensive drugs related to cancer susceptibility is currently generating a major debate in the scientific community, concerns in the public and emphasized interest from the media. The present article is a thorough review of what is known on the various classes of antihypertensive drugs concerning the risk of developing different neoplasms and about the suggested pathophysiological mechanisms, whenever available. The main limitations of evidence derived from studies currently available in this setting are also discussed, high-lightening the need for newly developed approaches to generate more accurate recommendations and informed advice for physicians.

Family history of esophageal cancer modifies the association of serum lipids and malignant esophageal lesions: a nested case-control study from the "Endoscopic Screening for Esophageal Cancer in China" trial

Background:

The association of lipids and cancer has varied greatly among different cancer types, lipid components and study populations. This study is aimed to investigate the association of serum lipids and the risk of malignant lesions in esophageal squamous epithelium.

Methods:

In the “Endoscopic Screening for Esophageal Cancer in China” (ESECC) trial, serum samples were collected and tested for total cholesterol (TC), triglycerides, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol at the time of subject enrollment. Cases were defined as malignant esophageal lesions identified by baseline endoscopic examination or by follow-up to May 31, 2018. Controls were randomly selected using incidence density sampling in the same cohort. Conditional logistic models were applied to identify the association of serum lipids and the risk of malignant esophageal lesions. Effect modification was evaluated by testing interaction terms of the factor under assessment and these serum lipid indicators.

Results:

No consistent association between serum lipid levels and esophageal malignant lesions were found in a pooled analysis of 211 cases and 2101 controls. For individuals with a family history of esophageal cancer (EC), high TC, and LDL-C were associated with a significantly increased risk of having malignant lesions (odds ratio [OR]_{High vs. Low TC} = 2.22, 95% confidence interval [CI]: 1.14–4.35; OR_{High vs. Low LDL-C} = 1.93, 95% CI: 1.01–3.65). However, a negative association was observed in participants without an EC family history (OR_{High vs. Low TC} = 0.69, 95% CI: 0.48–0.98, P_interaction = 0.002; OR_{High vs. Low LDL-C} = 0.50, 95% CI: 0.34–0.76, P_interaction < 0.001).

Conclusions:

In this study, we found that the association of serum lipids and malignant esophageal lesions might be modified by EC family history. The stratified analysis would be crucial for population-based studies investigating the association of serum lipids and cancer. The mechanism by which a family history of EC modifies this association warrants further investigation.

Fasting Blood Glucose, Cholesterol, and Risk of Primary Liver Cancer: The Kailuan Study

Purpose

The influence of fasting blood glucose (FBG) and cholesterolemia primary liver cancer (PLC) in China was analyzed via a large prospective cohort study based on a community population, and the combined effects between them were investigated.

Materials and Methods

Overall, 98,936 staff from the Kailuan Group who participated in and finished physical examinations between 2006 and 2007 were included in the cohort study. Their medical information was collected and they were followed up after examination. The correlations of serum FBG or total cholesterol (TC) with PLC were analyzed. Then, we categorized all staff into four groups: normal FBG/non-hypocholesterolemia, normal FBG/hypocholesterolemia, elevated FBG/non-hypocholesterolemia, elevated FBG/hypocholesterolemia, and normal FBG/non-hypocholesterolemia was used as a control group. The combined effects of elevated FBG and hypocholesterolemia with PLC were analyzed using the Age-scale Cox proportional hazard regression model.

Results

During 1,134,843.68 person-years follow-up, a total of 388 PLC cases occurred. We found the elevated FBG and hypocholesterolemia increase the risk for PLC, respectively. Compared with the non-hypocholesterolemia/normal FBG group, the risk of PLC was significantly increased in the non-hypocholesterolemia/elevated FBG group (hazard artio [HR], 1.19; 95% confidence interval [CI], 0.88 to 1.62) and hypocholesterolemia/normal FBG group (HR, 1.53; 95% CI, 1.19 to 1.97), and in the hypocholesterolemia/elevated FBG group (HR, 3.16; 95% CI, 2.13 to 4.69). And, a significant interaction effect was found of FBG and TC on PLC. All results were independent from the influence of liver disease.

Conclusion

Elevated serum FBG and hypocholesterolemia are risk factors for PLC, especially when combined. Thus, for the prevention and treatment of PLC, serum FBG and TC levels should be investigated.

LDL, HDL and endocrine-related cancer: From pathogenic mechanisms to therapies

Cholesterol is essential for a variety of functions in endocrine-related cells, including hormone and steroid production. We have reviewed the progress to date in research on the role of the main cholesterol-containing lipoproteins; low-density lipoprotein (LDL) and high-density lipoprotein (HDL), and their impact on intracellular cholesterol homeostasis and carcinogenic pathways in endocrine-related cancers. Neither LDL-cholesterol (LDL-C) nor HDL-cholesterol (HDL-C) was consistently associated with endocrine-related cancer risk. However, preclinical studies showed that LDL receptor plays a critical role in endocrine-related tumor cells, mainly by enhancing circulating LDL-C uptake and modulating tumorigenic signaling pathways. Although scavenger receptor type BI-mediated uptake of HDL could enhance cell proliferation in breast, prostate, and ovarian cancer, these effects may be counteracted by the antioxidant and anti-inflammatory properties of HDL. Moreover, 27-hydroxycholesterol a metabolite of cholesterol promotes tumorigenic processes in breast and epithelial thyroid cancer. Furthermore, statins have been reported to reduce the incidence of breast, prostate, pancreatic, and ovarian cancer in large clinical trials, in part because of their ability to lower cholesterol synthesis. Overall, cholesterol homeostasis deregulation in endocrine-related cancers offers new therapeutic opportunities, but more mechanistic studies are needed to translate the preclinical findings into clinical therapies.

Predicting the effect of statins on cancer risk using genetic variants from a Mendelian randomization study in the UK Biobank

Laboratory studies have suggested oncogenic roles of lipids, as well as anticarcinogenic effects of statins. Here we assess the potential effect of statin therapy on cancer risk using evidence from human genetics. We obtained associations of lipid-related genetic variants with the risk of overall and 22 site-specific cancers for 367,703 individuals in the UK Biobank. In total, 75,037 individuals had a cancer event. Variants in the HMGCR gene region, which represent proxies for statin treatment, were associated with overall cancer risk (odds ratio [OR] per one standard deviation decrease in low-density lipoprotein [LDL] cholesterol 0.76, 95% confidence interval [CI] 0.65-0.88, p=0.0003) but variants in gene regions representing alternative lipid-lowering treatment targets (PCSK9, LDLR, NPC1L1, APOC3, LPL) were not. Genetically predicted LDL-cholesterol was not associated with overall cancer risk (OR per standard deviation increase 1.01, 95% CI 0.98-1.05, p=0.50). Our results predict that statins reduce cancer risk but other lipid-lowering treatments do not. This suggests that statins reduce cancer risk through a cholesterol independent pathway.

Comorbidity Risk Score in Association with Cancer Incidence: Results from a Cancer Screenee Cohort

The combined effects of comorbidities can cause cancer incidence, while the effects of individual conditions, alone, might not. This study was conducted to investigate the joint impact of comorbidities on cancer incidence. The dietary score for energy-adjusted intake was calculated by applying a Gaussian graphical model and was then categorized into tertiles representing light, normal, and heavy eating behaviors. The risk point for cancer, according to the statuses of blood pressure, total cholesterol, fasting glucose, and glomerular filtration rate was computed from a Cox proportional hazard model adjusted for demographics and eating behavior. The comorbidity risk score was defined as the sum of the risk points for four comorbidity markers. We finally quantified the hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between the strata of the comorbidity risk score and cancer incidence. A total of 13,644 subjects were recruited from the Cancer Screenee Cohort from 2007–2014. The comorbidity risk score was associated with cancer incidence in a dose-dependent manner (HR = 2.15, 95% CI = 1.39, 3.31 for those scoring 16–30 vs. those scoring 0–8, P-trend < 0.001). Subgroup analysis still showed significant dose-dependent relationships (HR = 2.39, 95% CI = 1.18, 4.84 for males and HR = 1.99, 95% CI = 1.11, 3.59 for females, P-trend < 0.05). In summary, there was a dose-dependent impact of comorbidities on cancer incidence; Highlights: Previous studies have generally reported that hypertension, hypercholesterolemia, diabetes, and chronic kidney disease might predispose patients to cancer. Combining these chronic diseases into a single score, this study found a dose-dependent association between the data-driven comorbidity risk score and cancer incidence.

The Pivotal Role of the Dysregulation of Cholesterol Homeostasis in Cancer: Implications for Therapeutic Targets

Cholesterol plays an important role in cellular homeostasis by maintaining the rigidity of cell membranes, providing a medium for signaling transduction, and being converted into other vital macromolecules, such as sterol hormones and bile acids. Epidemiological studies have shown the correlation between cholesterol content and cancer incidence worldwide. Accumulating evidence has shown the emerging roles of the dysregulation of cholesterol metabolism in cancer development. More specifically, recent reports have shown the distinct role of cholesterol in the suppression of immune cells, regulation of cell survival, and modulation of cancer stem cells in cancer. Here, we provide a comprehensive review of the epidemiological analysis, functional roles, and mechanistic action of cholesterol homeostasis in regard to its contribution to cancer development. Based on the existing data, cholesterol homeostasis is identified to be a new key player in cancer pathogenesis. Lastly, we also discuss the therapeutic implications of natural compounds and cholesterol-lowering drugs in cancer prevention and treatment. In conclusion, intervention in cholesterol metabolism may offer a new therapeutic avenue for cancer treatment.

High Serum Levels of Cholesterol Increase Antitumor Functions of Nature Killer Cells and Reduce Growth of Liver Tumors in Mice

BACKGROUND AND AIMS

The relationship between serum cholesterol level and development of hepatocellular carcinoma (HCC) remains unclear. We investigated the effects of serum cholesterol level on development of liver tumors in mice.

METHODS

We performed studies with C57BL/6J mice, mice with disruption of the low-density lipoprotein receptor gene (Ldlr^-/-mice), and mice with conditional deletion of nature killer (NK) cells (NK^dele mice). Some C57BL/6J and NK^dele mice were given injections of diethylinitrosamine to induce liver tumor formation. Mice were placed on a normal diet (ND) or high-cholesterol diet (HCD) to induce high serum levels of cholesterol. We also studied mice with homozygous disruption of ApoE (ApoE^-/- mice), which spontaneously develop high serum cholesterol. C57BL/6J and NK^dele mice on the ND or HCD were implanted with Hep1-6 (mouse hepatoma) cells and growth of xenograft tumors and lung metastases were monitored. Blood samples were collected from mice and analyzed by biochemistry and flow cytometry; liver and tumor tissues were collected and analyzed by histology, immunohistochemistry, and RNA-sequencing analysis. NK cells were isolated from mice and analyzed for cholesterol content, lipid raft formation, immune signaling, and changes in functions. We obtained matched tumor tissues and blood samples from 30 patients with HCC and blood samples from 40 healthy volunteers; levels of cholesterol and cytotoxicity of NK cells were measured.

RESULTS

C57BL/6J mice on HCD and ApoE^-/- mice with high serum levels of cholesterol developed fewer and smaller liver tumors and lung metastases after diethylinitrosamine injection or implantation of Hep1-6 cells than mice on ND. Liver tumors from HCD-fed mice and ApoE^-/- mice had increased numbers of NK cells compared to tumors from ND-fed mice. NK^dele mice or mice with antibody-based depletion for NK cells showed similar tumor number and size in ND and HCD groups after diethylinitrosamine injection or implantation of Hep1-6 cells. NK cells isolated from C57BL/6J mice fed with HCD had increased expression of NK cell-activating receptors (natural cytotoxicity triggering receptor 1 and natural killer group 2, member D), markers of effector function (granzyme B and perforin), and cytokines and chemokines compared with NK cells from mice on ND; these NK cells also had enhanced cytotoxic activity against mouse hepatoma cells, accumulated cholesterol, increased lipid raft formation, and immune signaling activation. NK cells isolated from HCD-fed Ldlr^-/- mice did not have increased cholesterol content or cytotoxic activity against mouse hepatoma cells compared with ND-fed Ldlr^-/- mice. Serum levels of cholesterol correlated with number and activity of NK cells isolated from human HCCs.

CONCLUSIONS

Mice with increased serum levels of cholesterol due to an HCD or genetic disruption of ApoE develop fewer and smaller tumors after injection of hepatoma cells or a chemical carcinogen. We found cholesterol to accumulate in NK cells and activate their effector functions against hepatoma cells. Strategies to increase cholesterol uptake by NK cells can be developed for treatment of HCC.

Sex-specific clustering of metabolic risk factors and cancer risk: a longitudinal study in Iran

Background

Cancer is a major cause of death in low- and middle-income countries. A large number of studies have shown that some of the metabolic risk factors (MRFs) tend to cluster in individuals. We examined the synergistic effects of multiple MRFs and cancer risk among Iranian adults.

Methods

Among 8593 (3929 men) participants aged ≥ 30 years, the self-organizing map (SOM) was applied to clustering of four MRFs including high fasting plasma glucose (HFPG), high total cholesterol (HTC), high systolic blood pressure (HSBP), and high body mass index (HBMI). The Cox proportional hazards model was used to investigate the association between clusters with cancer incidence during a median of 14.0 years of follow-up.

Results

During the study period, 265 new cases of cancer were identified among participants at risk. The incidence density rate was 2.5 per 1000 person years in total population. About 32 and 40% of men and women, respectively, had three or four MRFs. We identified seven clusters of MRFs in both men and women. In both genders, MRFs were clustered in those with older age. Further, inverse associations were found between current smoking in men, and education level and passive smoking in women and clustering of MRFs. In men, a cluster with 100% HSBP and HBMI had the highest risk for overall cancer. While, among women, a cluster with 100% HFPG and 93% HBMI yielded the highest risk for cancer. The risk was decreased when HBMI accompanied by HTC.

Conclusions

Clustering patterns may reflect underlying link between MRFs and cancer and could potentially facilitate tailored health promotion interventions.

Body mass index and other risk factors for kidney cancer in men: a cohort study in Lithuania

OBJECTIVES

Previous studies have observed notable unexplained geographic differences in incidence of kidney cancer in Europe. Lithuania is among the countries with the highest incidence and mortality. Our objective was to investigate the effect of different lifestyle, anthropometric and biological factors on the risk of kidney cancer in Lithuanian men.

METHODS

This population-based cohort study included 6,849 men initially free from cancer. During the follow-up (1978-2008), 79 incident cases of kidney cancer were identified. Cox proportional hazards regression models were used to estimate hazard ratios (HR) and corresponding 95% confidence intervals (95% CI).

RESULTS

Risk of kidney cancer was significantly associated with increasing body mass index (BMI), the adjusted HR for ≥ 35 vs. < 25 kg/m² was 3.00, 95% CI 1.10-8.19 and the HR per 1 unit increment of BMI was 1.07, 95% CI 1.01-1.14. In overweight men (BMI ≥ 25 kg/m²), the HRs for kidney cancer per 10 mmHg increment of systolic or diastolic blood pressure were 1.10, 95% CI 0.96-1.25 and 1.26, 95% CI 1.01-1.56, respectively. We found no significant association between smoking, alcohol consumption or total serum cholesterol level and kidney cancer risk.

CONCLUSIONS

This study supports a link between increased BMI and the development of kidney cancer among men in Lithuania. Hypertension appears to be associated with risk of kidney cancer in overweight men, although the assessment was limited by the lack of statistical power.

The Metabolic Syndrome Is a Risk Factor for Breast Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

The metabolic syndrome (MetS) has been associated with the pathogenesis and prognosis of various malignant tumors. In this systematic review and meta-analysis, we explored the relationship between MetS and breast cancer (BC).

METHODS

Relevant studies were systematically searched on Ovid MEDLINE, Embase, Cochrane database, and PubMed up to September 16, 2019, using "breast cancer" and "metabolic syndrome" as keywords. Eligible studies with clear definition of MetS, available data, and relationships between MetS and BC were evaluated using a risk ratio (RR) and its 95% confidence interval (CI).

RESULTS

Twenty-five studies, including 13 cohort studies and 12 case-control studies, met the inclusion criteria, which assessed a total of 392,583 female participants and 19,628 BC patients. The results revealed a statistically significant increase by 52% of the risk of BC in adult females with MetS (RR = 1.49, 95% CI = 1.31-1.70, p < 0.0001). Postmenopausal MetS patients may have a twofold risk to suffer BC (RR = 2.01, 95% CI = 1.55-2.60, p < 0.001). The risk of BC increased markedly with the number of MetS components: RR = 1.00 for 1 component (p = 0.976), RR = 1.40 for 2 components (p = 0.121), and RR = 1.98 for >3 components (p < 0.001). The risk factors associated with BC were obesity, hypertension, and diabetes (RR = 1.33, 1.19, and 1.30 respectively, all p < 0.001).

CONCLUSIONS

Our study demonstrated that MetS is highly related with BC. In postmenopausal patients with ≥2 MetS components or a combination of obesity, hypertension, and diabetes, routine BC screening could help to detect BC at an early stage.

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.

Nutrition, lipidic parameters, and cancer risk and progress

The aim of this literature review is to analyze the association between lipidic parameters and cancer risk and progression, as there is no clear evidence that the risk or advancement of cancer increases with cholesterol levels. Some works suggest a positive, others a negative, and still others a neutral correlation between cancer advancement or risk and cholesterol-related parameters. This lack of a simple relationship indicates the need for a more complex, multi-variable, non-linear framework correlating lipid and cancer parameters, as well as the likely existence of optimum values of lipid parameters that may pave the way to cancer therapeutic strategies that include clinical nutrition.