Prevention of Tamoxifen-related Nonalcoholic Fatty Liver Disease in Breast Cancer Patients

The Effect of Menopausal Status, Insulin Resistance and Body Mass Index on the Prevalence of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is common and presents in a large proportion-up to 30%-of the global adult female population. Several factors have been linked with NAFLD in women, such as age, obesity, and metabolic syndrome. To extract appropriate details about the topic, we conducted an extensive search using various medical subject headings and entry terms including 'Menopause', 'Non-alcoholic fatty liver disease', 'Insulin resistance', and 'BMI'. This exhaustive search resulted in a total of 180 studies, among which only 19 were able to meet the inclusion criteria. While most of these studies indicated a significant rise in NAFLD prevalence among postmenopausal women, two did not find strong evidence linking menopause with NAFLD. Moreover, it was observed that women with NAFLD had higher insulin resistance levels and BMIs compared to those without the condition. In summary, it is important to consider specific factors like risk profile, hormonal status, and age along with metabolic components when treating women presenting with NAFLD. There is need for data-driven research on how gender affects the sensitivity of biomarkers towards NAFLD as well as the development of sex-specific prediction models-this would help personalize management approaches for women, who stand to benefit greatly from such tailored interventions.

Endocrine aspects of metabolic dysfunction-associated steatotic liver disease (MASLD): Beyond insulin resistance

While the association of metabolic dysfunction-associated steatotic liver disease (MASLD) with obesity and insulin resistance is widely appreciated, there are a host of complex interactions between the liver and other endocrine axes. While it can be difficult to definitively distinguish direct causal relationships and those attributable to increased adipocyte mass, there is substantial evidence of the direct and indirect effects of endocrine dysregulation on the severity of MASLD, with strong evidence that low levels of growth hormone, sex hormones, and thyroid hormone promote the development and progression of disease. The impact of steroid hormones, e.g. cortisol and dehydroepiandrosterone, and adipokines is much more divergent. Thoughtful assessment, based on individual risk factors and findings, and management of non-insulin endocrine axes is essential in the evaluation and management of MASLD. Multiple therapeutic options have emerged that leverage various endocrine axes to reduce the fibroinflammatory cascade in MASH.

Estrogen deprivation effects of endocrine therapy in breast cancer patients: Incidence, management and outcome

Endocrine therapy is one of the standard adjuvant treatments to reduce the risk of recurrence and mortality in patients with hormone receptor positive early breast cancer. Despite its proven efficacy, ET side effects, which persist over time even if low grade, may deteriorate quality of life. During follow-up visits, emphasis is generally placed on the risk of disease recurrence, while the topic of ET side effects is commonly neglected and discussed only briefly. This could lead to poor adherence to therapy and early treatment discontinuation, resulting in worse survival outcomes. The aim of this review is to provide an overview of the available evidence on the incidence and reporting of ET-related side effects (including vasomotor symptoms, musculoskeletal disorders and genitourinary syndrome of menopause, as well as fatigue, psychological and ocular disorders, dysmetabolic effects and loss of bone density) and of the pharmacological and non-pharmacological strategies available to mitigate symptom burden.

The Evidence Surrounding Non-Alcoholic Fatty Liver Disease in Individuals with Cancer: A Systematic Literature Review

Emerging evidence indicates an association between non-alcoholic fatty liver disease (NAFLD), cancer development and mortality. Cancer treatment-induced metabolic and hepatic dysfunction may be associated with increased rates of NAFLD. The review aims to investigate current evidence surrounding NAFLD in adults (≥18 years) with cancer including prevalence, effect of cancer treatments, metabolic co-morbidities, and mortality. Embase, Scopus, PubMed, and CINAHL were searched from inception to December 2021 including randomized controlled trials and observational studies. Twenty-three articles were included, comprising 142,218 participants. The overall risk of bias for observational studies was determined as low for 10 studies and neutral for 12 studies, and the RCT was determined as some concerns. The prevalence of NAFLD, based on imaging or histology, in adults with cancer ranged from 0.5 to 81.3%, with higher prevalence in breast, colorectal and gynecological cancers. Higher rates of NAFLD were also seen in patients who (i) underwent treatments-including chemotherapy and hormone therapy and/or who (ii) had higher BMI or other metabolic co-morbidities. NAFLD was associated with an increase in all-cause and cancer-related mortality. Based on review results, it is recommended that further assessment is carried out to determine whether liver screening in high-risk patients is cost effective and if interventions can be implemented to improve hepatic and health outcomes in adults with cancer.

Tamoxifen induced hepatic steatosis in high-fat feeding rats through SIRT1-Foxo1 suppression and LXR-SREBP1c activation

Background

Clinically, long-term use of tamoxifen (TAM) would lead to fatty liver disease in breast cancer patients, especially obese women. However, the exact mechanism of TAM-induced hepatic steatosis is still unclear. Meanwhile, there is no drug to prevent and treat it.

Aims and Methods

In view of silent information regulator 1 (SIRT1) playing a key role in hepatic lipid metabolism regulation, this study was conducted to investigate whether SIRT1 is a potential therapeutic target for TAM-induced hepatic steatosis. In this study, obese female Wistar rats fed with high-fat diet (HFD) for 15 weeks were given TAM (4, 8 mg/kg, intragastric) for 14 days. In vitro, human hepatocarcinoma cell line HepG2 was used to establish a high-fat model with 50 μM oleic acid and TAM (10 μM) was treated simultaneously for 72 h.

Results

The results showed that TAM was more likely to upregulate the expression of lipid synthetase that caused the increase of lipid content in HepG2 cells and rat liver. The expression of SIRT1 was downregulated both in vitro and in vivo. SIRT1 agonist SRT1720 (15 mg/kg, 30 mg/kg, i.p.) could resist TAM-induced hepatic lipid synthetase overexpression to relieve TAM-induced hepatic steatosis. Meanwhile, the upregulation of p-forkhead box O1 and LXRα induced by TAM was reversed by SRT1720.

Conclusions

These results indicated that TAM-induced hepatic steatosis was based on SIRT1-p-FoxO/LXRα-sterol regulatory element binding protein 1c pathway under HFD condition. SIRT1 agonist might be a potential therapeutic drug to relieve this side effect.

Highlights

Tamoxifen increased lipid synthesis and regulated lipid transport in HFD rat liver.p-FoxO1/LXRα-SREBP1c signaling was upregulated through the inhibition of SIRT1 in tamoxifen-induced hepatic steatosis under HFD condition.SIRT1 agonist SRT1720 could relieve tamoxifen-induced hepatic steatosis.

Development of a risk-stratification scoring system for predicting risk of breast cancer based on non-alcoholic fatty liver disease, non-alcoholic fatty pancreas disease, and uric acid

Many breast cancer patients have both non-alcoholic fatty liver disease (NAFLD) and non-alcoholic fatty pancreas disease (NAFPD). Consequently, we hypothesized that NAFPD and NAFLD were associated with breast cancer, and aimed to build a novel risk-stratification scoring system based on it. In this study, a total of 961 patients with breast cancer and 1,006 non-cancer patients were recruited. The clinical characteristics were collected and analyzed using logistic analysis. Risk factors were assessed by a risk rating system. Univariate analysis showed that body mass index, triglyceride, total cholesterol, NAFLD, NAFPD, low-density lipoprotein, and uric acid (UA) were significantly related to breast cancer. Among them, NAFLD, NAFPD, and UA were independent risk factors related to breast cancer identified by multivariate analysis. The risk assessment model was established based on these factors and demonstrated that the odds ratio sharply increased with the rising scores. Compared with the low-risk group, the odds ratio in the intermediate- and high-risk groups were 1.662 (1.380–2.001) and 3.185 (2.145–4.728), respectively. In conclusion, the risk-stratification scoring system combining NAFLD, NAFPD, and UA can accurately predict the occurrence of breast cancer.

Detailed Molecular Mechanisms Involved in Drug-Induced Non-Alcoholic Fatty Liver Disease and Non-Alcoholic Steatohepatitis: An Update

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are some of the biggest public health challenges due to their spread and increasing incidence around the world. NAFLD is characterized by intrahepatic lipid deposition, accompanied by dyslipidemia, hypertension, and insulin resistance, leading to more serious complications. Among the various causes, drug administration for the treatment of numerous kinds of diseases, such as antiarrhythmic and antihypertensive drugs, promotes the onset and progression of steatosis, causing drug-induced hepatic steatosis (DIHS). Here, we reviewed in detail the major classes of drugs that cause DIHS and the specific molecular mechanisms involved in these processes. Eight classes of drugs, among the most used for the treatment of common pathologies, were considered. The most diffused mechanism whereby drugs can induce NAFLD/NASH is interfering with mitochondrial activity, inhibiting fatty acid oxidation, but other pathways involved in lipid homeostasis are also affected. PubMed research was performed to obtain significant papers published up to November 2021. The key words included the class of drugs, or the specific compound, combined with steatosis, nonalcoholic steatohepatitis, fibrosis, fatty liver and hepatic lipid deposition. Additional information was found in the citations listed in other papers, when they were not displayed in the original search.

Fatty Liver in Hormone Receptor-Positive Breast Cancer and Its Impact on Patient's Survival

Purpose

Long-term estrogen inhibition may cause fatty liver disease (non-alcoholic fatty liver disease; NAFLD) among other adverse conditions such as osteoporosis, climacteric symptoms, thromboembolism, dyslipidemia, and metabolic syndrome. The prevalence of NAFLD among breast cancer patients ranges from 2.3%–45.2%. This study aimed to determine the risk factors for newly developed NAFLD among breast cancer patients after hormonal treatment and whether it influences survival outcomes.

Methods

This retrospective study investigated hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative (HR+/HER2−), nonmetastatic breast cancer patients diagnosed between January 2010 and December 2018. All patients received adjuvant hormonal treatment for at least 6 months. Clinical data on metabolic profile indicators such as body mass index (BMI), waist circumference, serum cholesterol, triglycerides, low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), diabetes, and presence of metabolic syndrome (MetS) were collected. In total, 160 eligible patients with complete covariate data and survival follow-up were included.

Results

NAFLD was diagnosed in 35% of patients. There were significant associations of being overweight (BMI ≥ 25 kg/m²), waist circumference > 80 cm, triglycerides ≥ 150 mg/dL, HDL-C ≤ 50 mg/dL, LDL-C < 150 mg/dL, and presence of MetS with the development of NAFLD. However, unlike other factors, MetS and HDL-C were not independently associated with NAFLD. Patients with breast cancer who developed NAFLD had longer disease-free survival (DFS). The median DFS was not reached in the NAFLD group, whereas it was 59.3 (45.6–73.0) months in the non-NAFLD group. No worsening of overall survival was observed in patients with breast cancer and NAFLD.

Conclusion

The development of NAFLD during treatment in patients with HR+/HER2− breast cancer was associated with several independent risk factors: being overweight, waist circumference, triglycerides, and LDL-C. Interestingly, breast cancer patients with NAFLD during treatment had longer DFS than those without NAFLD.

Luteolin mitigates tamoxifen-associated fatty liver and cognitive impairment in rats by modulating beta-catenin

BACKGROUND AND AIM

Tamoxifen (TAM) therapy has been associated with fatty liver diseases. Recently, multiple reports have also shown that TAM is related to cognitive impairment in patients with breast cancer. Luteolin, a natural flavonoid, has been traditionally used to treat various inflammatory disorders, such as chronic liver diseases, cognitive impairments, and cancers. This study aimed to evaluate the potential protective effects of luteolin against the cognitive defects and liver steatosis induced by TAM in rats.

EXPERIMENTAL APPROACH

The diseased group was subcutaneously (s.c) injected with TAM at a dose of 1 mg/kg daily for 7 days. The cotreated groups were given luteolin via oral gavage at a dose of 20 or 40 mg/kg concomitantly with s.c injection of TAM at a dose of 1 mg/kg for 7 days. All the groups were subjected to behavioral tests 24 h after the last TAM injection. Then, the rats were sacrificed 3 days after the last TAM injection.

RESULTS

Luteolin cotreatment significantly alleviated the behavioral defects in rats with TAM-induced cognitive impairment. This finding was supported by the reversal of neurodegeneration in the cortex and in the hippocampal regions of the brain. Furthermore, luteolin attenuated hepatic steatosis and decreased the levels of serum aminotransferases and hypertriglyceridemia. As an anti-inflammatory agent, luteolin cotreatment similarly decreased the levels of hepatic inflammatory markers and increased the levels of hepatic β-catenin in TAM-induced fatty liver.

CONCLUSIONS

Luteolin improved the TAM-induced cognitive impairment and hepatic steatosis in rats by alleviating inflammation and modulating hepatic β-catenin levels.

Chemotherapy-associated steatohepatitis

Some drugs may induce hepatotoxic lesions, such as steatosis or steatohepatitis found in Non-Alcoholic Fatty Liver Disease (NAFLD). Among these drugs there are some anti-tumoral molecules, such as methotrexate, 5-fluorouracil, irinotecan, tamoxifen and l-asparaginase. The hepatotoxic phenotype developed from treatment with such drugs is known as "CASH" for "Chemotherapy-induced Acute Steatohepatitis". The mechanism of toxicity is essentially based on mitochondrial toxicity. These lesions are chronic and often reversible when the treatment is stopped. Contributing factors related to the patient, the disease or the treatment play a major role in the emergence of CASH. It is important to identify chemotherapies with steatosis or steatohepatitis as risk factors in order to improve control of the metabolic risk factors associated with the patient and to reinforce monitoring during treatment. In the particular context of neo-adjuvant chemotherapy for metastatic colorectal cancer, a short duration of chemotherapy and a few-weeks delay between chemotherapy and surgery could reduce postoperative morbidity and mortality.

Sex Differences in Nonalcoholic Fatty Liver Disease: Estrogen Influence on the Liver-Adipose Tissue Crosstalk

Significance: Nonalcoholic fatty liver disease (NAFLD) is a hepatic and systemic disorder with a complex multifactorial pathogenesis. Owing to the rising incidence of obesity and diabetes mellitus, the prevalence of NAFLD and its impact on global health care are expected to increase in the future. Differences in NAFLD exist between males and females, and among females depending on their reproductive status. Clinical and preclinical data show that females in the fertile age are more protected against NAFLD, and studies in postmenopausal women and ovariectomized animal models support a protective role for estrogens. Recent Advances: An efficient crosstalk between the liver and adipose tissue is necessary to regulate lipid and glucose metabolism, protecting the liver from steatosis and insulin resistance contributing to NALFD. New advances in the knowledge of sexual dimorphism in liver and adipose tissue are providing interesting clues about the sex differences in NAFLD pathogenesis that could inspire new therapeutic strategies. Critical Issues: Sex hormones influence key master regulators of lipid metabolism and oxidative stress in liver and adipose tissue. All these sex-biased metabolic adjustments shape the crosstalk between liver and adipose tissue, contributing to the higher protection of females to NAFLD. Future Directions: The development of novel drugs based on the protective action of estrogens, but without its feminizing or undesired side effects, might provide new therapeutic strategies for the management of NAFLD. Antioxid. Redox Signal. 35, 753-774.

Can belly dance and mat Pilates be effective for range of motion, self-esteem, and depressive symptoms of breast cancer women?

OBJECTIVE

This study aims to analyse the effect of an intervention with belly dance or mat Pilates on range of motion, self-esteem and depressive symptoms in women with breast cancer receiving hormone therapy.

METHOD

A randomized clinical trial of 52 participants, diagnosed with breast cancer and undergoing adjuvant hormone therapy that were randomized and divided into three groups (1): Belly dance group, which received 16 weeks of Belly Dance classes 2) Mat Pilates group, that performed 16 weeks of Pilates intervention and (3) Control group, that received educational activities in the form of lectures and was invited to maintain its routine activities. The participants answered a questionnaire in which they contained the clinical and personal characteristics; quantification of the range of motion of the upper limbs using the Absolute Axis 360° digital goniometer; self-esteem by the Self-Esteem Scale (EAR) and depressive symptoms by the Beck Depression Inventory (BDI). All data was collected at two moments in the study, in the pre-intervention period (baseline) and at the end of the 16 weeks of intervention.

RESULTS

Only the variable range of motion variable showed significant results in all study groups (p = 0.025), with the Mat Pilates group having the best scores. Although not significant, the other study variables also improved after the intervention period.

CONCLUSION

Belly dance and the Mat Pilates can bring positive results in the range of movement of women undergoing adjuvant treatment of breast cancer, with the Pilates method being the one that most contributed to improvements in this variable.

Tamoxifen for the treatment of polycystic liver disease: A case report

RATIONALE

Polycystic liver disease is a rare disease characterized by the growth of numerous cysts in the liver. The liver function remains well preserved, but liver volumes can grow very large, and some patients ultimately need a liver transplantation. Other treatment options are limited and there is an unmet need for new therapeutic options.

PATIENT CONCERNS

We describe a 59-year-old patient with pain in the abdomen, especially when bending forward. Five years ago, she was diagnosed with breast cancer and as an incidental finding a couple of large liver cysts were diagnosed, explaining her abdominal pain.

DIAGNOSIS

Polycystic liver disease with several large liver cysts.

INTERVENTIONS

The patient was treated with tamoxifen, an estrogen receptor modulator, as treatment for her hormone receptor positive breast cancer. One of the liver cysts was aspirated.

OUTCOMES

In the 4.6 years after the start of tamoxifen treatment, 20 mg once daily, the volume of her liver cysts decreased remarkably. There was a reduction of combined cyst volume from 311 mL to 22 mL without percutaneous drainage.

LESSONS

Epidemiological as well as experimental evidence supports a pivotal role for estrogens as a driver for growth of polycystic livers. Estrogen antagonism has often been proposed as a therapeutic target, but supporting evidence is lacking in the literature. We hypothesize that the decrease in cyst size in this patient was caused by tamoxifen therapy, suggesting an in vivo antagonistic effect on cystic cholangiocytes. This is an important finding because tamoxifen could be a promising new treatment option for polycystic liver disease.

Hepatocrinology

Hepatocrinology is defined as a bidirectional, complex relationship between hepatic physiology and endocrine function, hepatic disease and endocrine dysfunction, hepatotropic drugs and endocrine function, and endocrine drugs and hepatic health. The scope of hepatocrinology includes conditions of varied etiology (metabolic, infectious, autoimmune, and invasive) that we term as hepato-endocrine syndromes. This perspective shares the definition, concept, and scope of hepatocrinology and shares insight related to this aspect of medicine. It is hoped that this communication will encourage further attention and research in this critical field.

Role of Steroid Hormones in the Pathogenesis of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease and may progress to cirrhosis or even hepatocellular carcinoma. A number of steroid hormones are important regulators of lipid homeostasis through fine tuning the expression of genes related to lipid synthesis, export, and metabolism. Dysregulation of such pathways has been implicated in the pathogenesis of NAFLD. The aim of this review is to clarify the potential impact of steroid hormones on NAFLD. We also highlight potential interventions through modulating steroid hormone levels or the activities of their cognate receptors as therapeutic strategies for preventing NAFLD.

Risk of fatty liver after long-term use of tamoxifen in patients with breast cancer

Background

Few studies report the effects of tamoxifen intake and the occurrence of de novo fatty liver and the deterioration of existing fatty liver. The aim of this study was to investigate the effects of tamoxifen on fatty change of liver over time and also the impact of fatty liver on the prognosis of patients with breast cancer.

Methods

This was a single-center, retrospective study of patients who were diagnosed with primary breast cancer from January 2007 to July 2017. 911 consecutive patients were classified into three groups according to treatment method: tamoxifen group, aromatase inhibitor (AI) group, and control group.

Results

Median treatment duration was 49 months (interquartile range, IQR; 32–58) and median observational period was 85 months (IQR; 50–118). Long-term use of tamoxifen significantly aggravated fatty liver status compared to AI or control groups [hazard ratio (HR): 1.598, 95% confidence interval (CI): 1.173–2.177, P = 0.003] after adjusting other factors. When analyzed separately depending on pre-existing fatty liver at baseline, tamoxifen was involved in the development of de novo fatty liver [HR: 1.519, 95% CI: 1.100–2.098, P = 0.011) and had greater effect on fatty liver worsening (HR: 2.103, 95% CI: 1.156–3.826, P = 0.015). However, the progression of fatty liver did not significantly affect the mortality of breast cancer patients.

Conclusions

Tamoxifen had a significant effect on the fatty liver status compared to other treatment modalities in breast cancer patients. Although fatty liver did not affect the prognosis of breast cancer, meticulous attention to cardiovascular disease or other metabolic disease should be paid when used for a long time.

A prospective, randomized study of Toremifene vs. tamoxifen for the treatment of premenopausal breast cancer: safety and genital symptom analysis

Background

Toremifene (TOR) is a selective oestrogen receptor modulator (SERM) and has comparable efficacy to that of tamoxifen (TAM) in breast cancer patients. Herein, we compared the safety of TOR to that of TAM in the adjuvant treatment of premenopausal breast cancer.

Methods

This was a prospective randomized and open-label clinical study. Premenopausal patients with hormonal receptor (HR)-positive early breast cancer were randomly assigned (1:1) to receive TOR) or TAM treatment. The follow-up period was 1 year. The primary end point was the incidence of ovarian cysts, and secondary end points were the incidence of endometrial thickening, changes in female hormones, the incidence of fatty liver, changes in the modified Kupperman index (mKMI) and changes in quality of life.

Results

There were 92 patients in the final analysis. The incidences of ovarian cysts were 42.6% in the TOR group and 51.1% in the TAM group (p = 0.441). Forty-one patients (87.2%) in the TOR group and 36 patients (80.0%) in the TAM group experienced endometrial thickening (p = 0.348). The proportions of patients with fatty liver were 31.9% in the TOR group and 26.7% in the TAM group (p = 0.581). No significant differences in the mKMI or quality of life were observed between the two groups.

Conclusions

TOR and TAM have similar side effects on the female genital system and quality of life in premenopausal early breast cancer patients.

Trial registration

ClinicalTrials.gov NCT02344940. Registered 26 January 2015 (retrospectively registered).

Effects of exercise on physical outcomes of breast cancer survivors receiving hormone therapy - A systematic review and meta-analysis

BACKGROUND

Side-effects of hormone therapy can impair the physical health of breast cancer survivors. Exercise has been clearly shown to improve the quality of life of breast cancer survivors. Less is known about the effects of exercise on physical outcomes for breast cancer survivors receiving hormone therapy.

OBJECTIVE

To investigate the effects of exercise on physical outcomes of breast cancer survivors receiving hormone therapy.

METHODS

Five electronic databases were searched by two authors using the terms "Breast Neoplasms" [MeSH] and "Tamoxifen" [MeSH] and "Aromatase Inhibitors" [MeSH] and "Exercise" [MeSH]. Randomized and non-randomized clinical trials were included. Risk of bias was assessed by the Cochrane Collaboration tool and ROBINS-I, and the quality of evidence was evaluated using GRADE. Pooled effects were reported as standardized mean differences (SMDs) and 95 % confidence intervals (CIs) using a random effects model.

RESULTS

Eleven studies were included in the meta-analysis. Two hundred and fourteen breast cancer survivors receiving hormone therapy, tamoxifen, or aromatase inhibitors participated in interventions based on aerobic plus resistance exercise or walking activity. The physical outcomes reported in the articles were: cardiorespiratory fitness, pain, bone mineral density, grip strength, and body fat percentage. Exercise effects were found only for cardiorespiratory fitness (SMD = 0.37; 95 % CI: 0.11; 0.63; I² = 93 %) and pain (SMD = -0.55; IC95 % -1.11; -0.00; I² = 80 %), with low quality of evidence. No effects were observed for the other variables.

CONCLUSIONS

Aerobic plus resistance exercise had positive effects on cardiorespiratory fitness and pain in breast cancer survivors receiving hormone therapy. However, high-quality randomized clinical trials are required to confirm this finding.

Prevalence, incidence and risk factors of tamoxifen-related non-alcoholic fatty liver disease: A systematic review and meta-analysis

BACKGROUND & AIMS

Tamoxifen is associated with an increased risk of developing fatty liver. The aim of this systematic review and meta-analysis was to evaluate the prevalence and incidence of fatty liver developed after tamoxifen treatment in breast cancer patients.

METHODS

A systematic search of PubMed (Medline), EMBASE, OVID Medline, the Cochrane Library and other databases was performed for this review. The abstracts obtained from the search were reviewed by two investigators who chose manuscripts for full-text review. The event rates were calculated with a random-effects model and quality-effects model.

RESULTS

The search yielded 165 references. Of these, 24 were included in the quantitative summary. We analysed the data of a total of 6,962 patients treated with tamoxifen and 975 patients not treated with tamoxifen. The prevalence of fatty liver among patients with breast cancer taking tamoxifen was 40.25 per 100 patients and the incidence rate was 12.37 per 100 person-years. The incidence of fatty liver was much higher in the tamoxifen group than in the control group [incidence rate ratio: 3.12, 95% CI (confidence interval): 2.05-4.75, I²  = 61%], regardless of region. The main risk factors were body mass index (BMI) [hazard ratio (HR): 1.15, 95% CI: 1.09-1.22] and hypercholesterolaemia (HR: 1.01, 95% CI: 1.00-1.02).

CONCLUSION

The use of tamoxifen was associated with increased risks in the incidence and prevalence of fatty liver, especially in patients with high BMI and hypercholesterolaemia.

Tamoxifen-induced hepatotoxicity via lipid accumulation and inflammation in zebrafish

Tamoxifen is a clinical drug for estrogen receptor (ER)-positive breast cancer. Recently, it has been detected in aquatic environment. The residual drugs will produce certain biological activity and create a risk to aquatic organism when they enter the water environment. Therefore, it has great significance to study the ecotoxicity of tamoxifen. In the study, we used zebrafish as a model of aquatic to investigate the ecotoxic mechanism of tamoxifen to aquatic. We found that tamoxifen induced liver lipid accumulation in zebrafish, which showed a significant hepatotoxicity with smaller liver area and bigger yolk area. Though biochemical and pathologic measurement, tamoxifen treated group showed higher transaminase and lipid content. The elevated liver lipid synthesis might due to the increase of lipid metabolism related gene Srebf1, Srebf2 and Fasn. Moreover, inflammatory cytokine Tnf-α, Il-1β And Il-6 were increased. This result confirmed the toxicity of tamoxifen to aquatic, suggested liver injury was the main characteristic of its ecotoxicity. This study indicated it is important to avoid tamoxifen discharging into the aquatic ecology and provided a theoretical basis of prevention tamoxifen-induced ecotoxicity to aquatic.

Drug-induced liver injury in obesity and nonalcoholic fatty liver disease

Obesity is commonly associated with nonalcoholic fatty liver (NAFL), a benign condition characterized by hepatic lipid accumulation. However, NAFL can progress in some patients to nonalcoholic steatohepatitis (NASH) and then to severe liver lesions including extensive fibrosis, cirrhosis and hepatocellular carcinoma. The entire spectrum of these hepatic lesions is referred to as nonalcoholic fatty liver disease (NAFLD). The transition of simple fatty liver to NASH seems to be favored by several genetic and environmental factors. Different experimental and clinical investigations showed or suggested that obesity and NAFLD are able to increase the risk of hepatotoxicity of different drugs. Some of these drugs may cause more severe and/or more frequent acute liver injury in obese individuals whereas others may trigger the transition of simple fatty liver to NASH or may worsen hepatic lipid accumulation, necroinflammation and fibrosis. This review presents the available information regarding drugs that may cause a specific risk in the context of obesity and NAFLD. These drugs, which belong to different pharmacological classes, include acetaminophen, halothane, methotrexate, rosiglitazone and tamoxifen. For some of these drugs, experimental investigations confirmed the clinical observations and unveiled different pathophysiological mechanisms which may explain why these pharmaceuticals are particularly hepatotoxic in obesity and NAFLD. Because obese people often take several drugs for the treatment of different obesity-related diseases, there is an urgent need to identify the main pharmaceuticals that may cause acute liver injury on a fatty liver background or that may enhance the risk of severe chronic liver disease.