Evaluation of Antioxidant Intakes in Relation to Inflammatory Markers Expression Within the Normal Breast Tissue of Breast Cancer Patients

Multi-Omics Analysis Reveals Age-Related Microbial and Metabolite Alterations in Non-Human Primates

Aging is a systemic physiological degenerative process, with alterations in gut microbiota and host metabolism. However, due to the interference of multiple confounding factors, aging-associated molecular characteristics have not been elucidated completely. Therefore, based on 16S ribosomal RNA (rRNA) gene sequencing and non-targeted metabolomic detection, our study systematically analyzed the composition and function of the gut microbiome, serum, and fecal metabolome of 36 male rhesus monkeys spanning from 3 to 26 years old, which completely covers juvenile, adult, and old stages. We observed significant correlations between 41 gut genera and age. Moreover, 86 fecal and 49 serum metabolites exhibited significant age-related correlations, primarily categorized into lipids and lipid-like molecules, organic oxygen compounds, organic acids and derivatives, and organoheterocyclic compounds. Further results suggested that aging is associated with significant downregulation of various amino acids constituting proteins, elevation of lipids, particularly saturated fatty acids, and steroids. Additionally, age-dependent changes were observed in multiple immune-regulatory molecules, antioxidant stress metabolites, and neurotransmitters. Notably, multiple age-dependent genera showed strong correlations in these changes. Together, our results provided new evidence for changing characteristics of gut microbes and host metabolism during aging. However, more research is needed in the future to verify our findings.

Association of Dietary Intake of Zinc and Selenium with Breast Cancer Risk: A Case-Control Study in Chinese Women

As major nonenzymatic antioxidant components in the body, dietary Zinc (Zn) and Selenium (Se) may have an impact on breast cancer development. This study aimed to investigate the relationship between dietary Zn, Se intake and breast cancer risk in Chinese women. The case-control study included 1591 cases and 1622 age-frequency matched controls. Dietary intake was collected using a validated food frequency questionnaire. Dietary Zn and Se were divided into four categories: Zn/Se from plants, Zn/Se from meat, Zn/Se from red meat, and Zn/Se from white meat. Unconditional logistic regression models and restricted cubic spline analyses were performed to identify potential associations. Zn from white meat intake was linearly and inversely associated with breast cancer risk, and Se from red meat intake was linearly and positively associated with breast cancer risk, with adjusted odds ratio and 95% confidence interval of 0.76 (0.61-0.95) and 1.36 (1.04-1.77), respectively. Non-linear relationships were found between total dietary Zn, Zn from meat, Zn from red meat intake and breast cancer risk (p_{non-linearity} < 0.05). In conclusion, dietary Zn and Se intake were associated with breast cancer risk in Chinese women, and the optimal intake of Zn may be beneficial for breast cancer prevention.

Inflammaging as a target for healthy ageing

Life expectancy has been on the rise for the past few decades, but healthy life expectancy has not kept pace, leading to a global burden of age-associated disorders. Advancing age is accompanied by a chronic increase in basal systemic inflammation, termed inflammaging, contributing towards an increased risk of developing chronic diseases in old age. This article reviews the recent literature to formulate hypotheses regarding how age-associated inflammaging plays a crucial role in driving chronic diseases and ill health in older adults. Here, we discuss how non-pharmacological intervention strategies (diet, nutraceutical supplements, phytochemicals, physical activity, microbiome-based therapies) targeting inflammaging restore health in older adults. We also consider alternative existing pharmacological interventions (Caloric restriction mimetics, p38 mitogen-activated protein kinase inhibitors) and explore novel targets (senolytics) aimed at combating inflammaging and optimising the ageing process to increase healthy lifespan.

Dietary Antioxidant Insufficiency Is Associated With Increased Inflammatory Markers and Poorer Health-Related Quality of Life in Patients With Heart Failure

BACKGROUND

Antioxidant insufficiency, elevated inflammatory markers, and poor health-related quality of life (HRQOL) are prevalent in patients with heart failure (HF).

OBJECTIVE

The objective of this study was to examine the associations among dietary antioxidant intake, inflammatory markers, and HRQOL in patients with HF.

METHODS

This was a secondary analysis of 265 patients with HF who completed a 4-day food diary. We assessed intake of 10 antioxidants: alpha carotene, beta carotene, beta cryptoxanthin, lutein, zeaxanthin, lycopene, vitamins C and E, zinc, and selenium. Antioxidant insufficiency was reflected by a measured level for each antioxidant that was below the estimate average requirement or lower than median for antioxidants without an estimate average requirement. Inflammatory markers including serum C-reactive protein, cytokines (interleukins 6 and 10), tumor necrosis factor-alpha, and soluble receptors (sTNFR1 and sTNFR2) were assessed with enzyme immunoassay. Health-related quality of life was measured using the Minnesota Living with Heart Failure at 12 months.

RESULTS

Dietary antioxidant insufficiency predicted C-reactive protein (β = 0.135, P = .032) and interleukin 10 (β = -.155, P = .027). Patients with higher antioxidant insufficiency had higher C-reactive protein and lower interleukin 10. Both antioxidant insufficiency (β = 0.13, P = .049) and higher C-reactive protein (β = 0.16, P = .019) were independently associated with poorer HRQOL while adjusting for covariates.

CONCLUSIONS

Dietary antioxidant insufficiency was associated with increased markers of inflammation and poorer HRQOL. Improvement of diet quality among patients with HF may be a fruitful area of research for enhancing HRQOL.

Lycopene as a Potential Bioactive Compound: Chemistry, Extraction, and Anticancer Prospective

Lycopene, a potential bioactive agent, is a non-pro-vitamin A carotenoid recognized as a potent antioxidant. It is extracted from plants like tomatoes, watermelons, red carrots and papayas and has remarkable health benefits. A significant amount of research has been assisted to date to establish the anticancer activity of lycopene. Our review enhances information about the promising anticancer potential of this compound. The biological activity of lycopene has been described in several studies in regard to pancreatic, breast, prostate, liver, gastric, ovarian, kidney, skin, intestine, brain and spinal cord cancers. Lycopene resists cancer by inhibition of apoptosis, induction of cell proliferation, cell invasion, cell cycle development, metastasis and angiogenesis. The mechanisms of anticancer action of lycopene are attributed to the management of certain signal transduction pathways, such as modulation of insulin-like growth factors system, PI3K/Akt pathway, modification of important gene expression, inhibit the activity of sex steroid hormones, and the conversation of mitochondrial behavior. Hence, this review focuses on current knowledge of sources, extraction techniques, and chemistry of lycopene, as well as the prospective mechanisms of action related with its anticancer activity. Also, it summarizes the background information about lycopene and the most current research with consideration to its aspect in treating several types of cancer together with future directions.

Association between vitamin D and calcium intakes, breast microcalcifications, breast tissue age-related lobular involution and breast density

OBJECTIVE

To demystify the potential role of vitamin D and calcium intakes in breast carcinogenesis, we explored the association between these two nutrients and three biomarkers of breast cancer risk: the presence of microcalcifications, age-related lobular involution and breast density.

METHODS

A total of 82 premenopausal and 79 postmenopausal women diagnosed with breast cancer completed a food frequency questionnaire to assess their total vitamin D and calcium intakes. Presence of microcalcifications was determined by reviewing pathology reports. Age-related lobular involution was assessed in nontumoral breast tissue on hematoxylin-eosin-stained slides and percent breast density was assessed by a computer-assisted method. Multivariate generalized linear models were used to evaluate associations between quartiles of vitamin D and calcium intakes and the biomarkers of breast cancer risk.

RESULTS

Increasing quartiles of vitamin D intake were inversely associated with the presence of microcalcifications (fourth quartile [Q4] prevalence ratio [PR] = 0.55; Ptrend = 0.021) and breast density (Q4-Q1 = -7.7%; Ptrend = 0.023) in postmenopausal women, and positively associated with age-related lobular involution in women with microcalcifications (Q4 PR = 1.62; Ptrend = 0.036). Increasing quartiles of calcium intake were inversely associated with microcalcifications among all (Q4 PR = 0.44), premenopausal (Q4 PR = 0.37) and postmenopausal women (Q4 PR = 0.38; Ptrend < 0.014 for all). It was also inversely associated with breast density in women without microcalcification (Q4-Q1 = -8.3%; Ptrend = 0.047), but positively associated with breast density in women with microcalcifications (Q4-Q1 = 10.0%; Ptrend = 0.032).

CONCLUSIONS

Results suggest that the association between vitamin D and calcium intakes and breast cancer risk factors could be influenced by the presence of microcalcifications.

Índice de Fitoquímicos da Dieta: Aplicação com Pacientes em Tratamento Oncológico

Introdução: O tratamento do câncer provoca efeitos adversos que podem alterar o consumo alimentar e, consequentemente, a ingestão de vitaminas, minerais, fibras e fitoquímicos. Objetivo: Aplicar o Índice de Fitoquímicos (IF) da dieta nos registros alimentares de pacientes em tratamento oncológico. Método: Estudo transversal com indivíduos em tratamento oncológico. Foram coletadas informações sociodemográficas e clínicas dos participantes para caracterização da população. Os dados alimentares foram obtidos por meio de recordatório alimentar de 24 horas e inseridos no software Nutrabem Pro® para obtenção dos valores de macro e micronutrientes, bem como dos fitoquímicos. Para avaliar o IF, aplicou-se a fórmula proposta por McCarty. Resultados: Participaram do estudo 50 pacientes predominantemente do sexo feminino e com média da idade de 58±12,1 anos. A média geral do IF foi de 20,44±11,55, e a ordem crescente de consumo foi: luteína-zeaxantina, alfacaroteno, licopeno, criptoxantina e betacaroteno. Os alimentos que mais contribuíram para a ingestão dos fitoquímicos foram: beterraba, cenoura e abóbora-japonesa para beta e alfacaroteno; laranja e mamão para betacriptoxantina; molho de tomate, melancia e mamão para licopeno; almeirão e beterraba para luteína/zeaxantina; e maçã, banana e azeite para fitoesterol. O IF não se associou com as variáveis sociodemográficas e clínicas da população. Conclusão: Os pacientes em tratamento oncológico apresentaram baixo consumo de fitoquímicos. Esse resultado condiz com a ingestão insuficiente de frutas e hortaliças, as quais representam as principais fontes de carotenoides nas refeições, além do baixo consumo de oleaginosas e sementes, que configuram uma importante fonte de fitoesteróis.

Effects of Vitamin E on Doxorubicin Cytotoxicity in Human Breast Cancer Cells in Vitro

OBJECTIVE

This study aimed to evaluate in vitro synergistic anticancer effect of doxorubicin combined with Vitamin E.

METHODS

The MTT assay was utilized to assess the cytotoxicity of Vitamin E and vitamin E combined with doxorubicin and vital activities of SKBR3, MDA-MB-231, and HFF cells over a 24-hour incubation period. In addition, the antioxidant properties of these interventions and the decrease of reactive oxygen species (ROS) content caused by the treatment were evaluated.

RESULTS

The antiproliferative effect of doxorubicin increased significantly in combination with vitamin E (Doxcorobicin 2µM vs. Vitamin E 120µM, P=0.000). Despite reducing cell ROS content due to vitamin E treatment, the combination of vitamin E and doxorubicin showed no significant synergistic effect (Doxcorobicin 2µM vs. Vitamin E 120µM, P=0.998).

CONCLUSION

This study indicated that the doxorubicin-vitamin E treatment reduced the viability of breast cancer cells with the minimum side effects on normal cells. In addition, the high dosage of vitamin E intensified the cytotoxicity of doxorubicin.

Histopathological prognosis of papillary thyroid carcinoma associated with nutritional status of vitamins A and E

BACKGROUND/OBJECTIVES

Experimental and clinical studies have shown that vitamins A and E can inhibit cancer formation and progression. The unfavourable status of these vitamins can represent risk factors for the disease. This study aimed to evaluate the associations between the nutritional status of vitamins A and E (serum levels and dietary intake) and histopathological outcomes in Papillary Thyroid Carcinoma (PTC) patients.

SUBJECTS/METHODS

We applied a cross-sectional study (2017-2018) and quantified retinol (ROH) and α-tocopherol (TOH) serum levels and vitamins dietary intake of 46 PTC patients. Serum vitamins were quantified by high efficiency liquid chromatography and vitamins dietary intake was analyzed by 24-hr dietary recalls.

RESULTS

Patients with lower ROH serum levels were more likely to present lymph node metastasis and/or angiolymphatic invasion (p = 0.025). In addition, higher vitamin A and vitamin E intake are related to the absence of extrathyroidal extension (p = 0.013) and lymph node metastasis (p = 0.007), respectively. Our findings suggest that a ROH serum level greater than 2.65 μmol/L in PTC patients may be a protective factor against the presence of lymph node metastasis and angiolymphatic invasion. In addition, vitamin A and E intake may protect against extrathyroidal extension and lymph node metastasis.

CONCLUSIONS

A favourable nutritional status (higher serum levels and/or intake) of vitamin A and E may be associated with less aggressive tumours in PTC patients.

Association of dietary total antioxidant capacity with anthropometric indicators, C-reactive protein, and clinical outcomes in hospitalized oncologic patients

OBJECTIVE

Many studies have shown an inverse association between higher dietary total antioxidant capacity (DTAC) and chronic non-communicable diseases, including cancer. The aim of this study was to evaluate the association of the DTAC with anthropometric and biochemical indicators and clinical outcomes in hospitalized patients with cancer.

METHODS

A cross-sectional study was carried out with 196 hospitalized patients diagnosed with cancer. The DTAC, determined by the ferric-reducing antioxidant power method, was calculated using a validated standard spreadsheet. Multivariate linear regression was used to assess the association, identifying anthropometric indicators that were associated with DTAC and the variables of interest. P < 0.05 was statistically significant.

RESULTS

The individuals included in the last tertile of DTAC presented lower occurrences of death (P = 0.032), constipation (P = 0.010), dysphagia (P = 0.010), painful swallowing and chewing (P = 0.019), and dehydration (P = 0.032) than individuals in the first tertile. The C-reactive protein values were significantly lower (P = 0.010) and handgrip strength values were higher (P = 0.037) in individuals in the third tertile than in the other participants.

CONCLUSIONS

DTAC was associated with a better prognosis of hospitalized cancer patients, considering signs and symptoms of nutritional impact, as well as the inflammatory state of the patients. These factors may influence the length of hospital stay and mortality. The findings of this research provide important information for a preventive and nutritional management perspective in this population.

Psychotherapy with Music Intervention Improves Anxiety, Depression and the Redox Status in Breast Cancer Patients Undergoing Radiotherapy: A Randomized Controlled Clinical Trial

The aim of this study was to assess the effects of psychotherapy with music intervention (PMI) on anxiety, depression, redox status, and inflammation in breast cancer patients undergoing radiotherapy (RT). This monocentric randomized clinical trial recruited 60 patients who had a breast cancer operation and were undergoing postoperative RT. Eligible patients were randomized (1:1) in two groups: the control group (CG) received treatment as usual (n = 30), i.e., RT alone; the intervention group (PMI) received RT and psychotherapy with music intervention (n = 30), which was delivered in a group setting. Five patients were excluded after randomization. Assessments were performed at baseline (T0), at the end of RT (T1), and three months after the end of RT (T2). The main objectives of the study were the assessment of anxiety/depression, plasma glutathione (GSH), and thiobarbituric acid reactive substances (TBARS) in the two arms of the study. Our findings revealed a positive effect of PMI on anxiety, depression, resilience, and quality of life. Furthermore, a positive effect of PMI on redox status was found for the first time. Thus, in the PMI group, we found a significant increase of GSH (mean change 2.2 95%, CI 0.7 to 3.7) and a significant reduction of TBARS (mean change -1.1 95%, CI -1.8 to -0.3) at T2 vs. T0.

The Role of Vitamin E in Breast Cancer Treatment and Prevention: Current Perspectives

Background:

Regarding the multifactorial etiology of breast cancer, food choices, as well as dietary intake, are the main modified factors in cancer prevention. In this sense, understanding molecular pathways involved in breast cancer proliferation can help determine the mechanisms of action of organic compounds such as antioxidant vitamins that are known to protect against cancer.

Objective:

Assess the mechanism of action of vitamin E in breast cancer modulation, with emphasis on important markers of tumor development.

Methods:

It is a systematic review carried out in PubMed and Web of Science databases, from the last 5 years, in Portuguese, English and Spanish. The following terms were selected according to The Medical Subject Headings (MeSH): “breast cancer” OR “breast neoplasms”, “tocopherol” OR “tocotrienols” OR “vitamin E”, as equated terms.

Results:

A total of 595 articles were found and 25 were selected according to inclusion criteria. Vitamin E has been related to suppression/overexpression of important tumorigenic pathways, mainly associated with proliferation, energy metabolism, chemosensitivity and invasion/metastasis. Clinical studies of vitamin E supplementation are needed to assess the dose/response effect on breast cancer patients.

Conclusion:

The safety of vitamin E supplementation is still controversial due to current studies design available. However, when vitamin E is supplemented, the dose and therapeutic regimen must be carefully decided, including the route of administration and breast cancer subtypes to enhance desired effects and minimize unwanted side effects.

Hybrid Dietary-Blood Inflammatory Profiles and Postmenopausal Breast Cancer: A Case-Control Study

The carcinogenesis process is associated with inflammation, which can be modified by diet. There is limited evidence regarding the inflammatory status and diet in association with breast cancer (BC). The aim of this study was to investigate the association of hybrid dietary-blood inflammatory profiles (HD-BIPs) with postmenopausal breast cancer occurrence. The case-control study was conducted among 420 women (230 controls, 190 primary BC cases) aged 40–79 years from north-eastern Poland. Blood levels of C-reactive protein (CRP), interleukin-6 (IL-6) and leukocyte count were marked in 129 postmenopausal women (82 controls, 47 cases). The 62-item food frequency questionnaire (FFQ-6) was used to the dietary data collection. Two HD-BIPs were found using the Principal Component Analysis (PCA). The “Pro-healthy/Neutral-inflammatory” profile was characterized by the frequent consumption of wholemeal cereals/coarse groats, legumes, vegetables, fruits, nuts/seeds and fish. The “Unhealthy/Pro-inflammatory” profile was characterized by the frequent consumption of red/processed meats, animal fats, sugar/honey/sweets, refined cereals/fine groats, and an increased concentration of CRP, IL-6 and granulocyte-to-lymphocyte ratio. The lower odds ratio (OR) of breast cancer was associated with the higher adherence to the “Pro-healthy/Neutral-inflammatory” profile (OR = 0.38; 95% Cl: 0.18–0.80; p < 0.01 for the higher level vs. lower level, crude model; OR for one-point score increment: 0.61; 95% Cl: 0.42–0.87; p < 0.01, adjusted model). The higher OR of breast cancer was associated with the higher adherence to the “Unhealthy/Pro-inflammatory” profile (OR = 3.07; 95%Cl: 1.27–7.44; p < 0.05 for the higher level v.s. lower level, adjusted model; OR for one-point score increment: 1.18; 95%Cl: 1.02–1.36; p < 0.05, adjusted model). This study revealed that the consumption of highly processed, high in sugar and animal fat foods should be avoided because this unhealthy diet was positively associated with postmenopausal breast cancer occurrence through its pro-inflammatory potential. Instead, the frequent consumption of low-processed plant foods and fish should be recommended since this pro-healthy diet was inversely associated with the cancer occurrence even though its anti-inflammatory potential has not been confirmed in this study sample.

Evaluation of the Diagnostic and Predicative Values of 8-Iso-Prostaglandin F2α as a Biomarker of Breast Cancer

BACKGROUND

Breast cancer (BC) is a commonly reported cancer that is widely prevalent among women. Its early detection improves patient survival and results in better outcomes. For diagnosis and follow-up care, tumor markers are one of the feasible investigations to be ordered. 8-Iso-prostaglandin F2α (8-iso-PGF2α) serves as a serum marker reflecting oxidative stress and subsequent damaging of DNA. In the present study, we aimed to evaluate both diagnostic and predictive values of 8-iso-PGF2α in BC patients.

MATERIALS AND METHODS

Serum levels of 8-iso-PGF2α were assessed for 66 women with benign breast tumors and 65 women who had malignant BC. To compare the patients who had breast tumors with healthy individuals, 63 women free of breast diseases were selected as controls.

RESULTS

The serum level of 8-iso-PGF2α in the BC patients (57.92 pg/mL) was significantly higher compared to those with benign tumors (18.89 pg/mL) (p < 0.001). In addition, individuals with no breast diseases had less 8-iso-PGF2α (4.02 pg/mL) compared to those who had developed a tumor (p < 0.001). Serum 8-iso-PGF2α was found to be positively correlated with both carcinoembryonic antigen (r = 0.74, p < 0.001) and cancer antigen 15-3 (r = 0.80, p < 0.001). Furthermore, serum 8-iso-PGF2α showed high diagnostic performance in BC (AUC = 0.999, sensitivity = 100%, specificity = 99.2% at a cutoff value of 36.18 pg/mL).

CONCLUSIONS

Our study found that the high level of serum 8-iso-PGF2α helps to provide a non-invasive indicator to detect BC. Future work with a larger sample size and various phases of BC can confirm the current results which provide insights into the early detection of cancer.

Cellular Mechanisms of Circulating Tumor Cells During Breast Cancer Metastasis

Circulating tumor cells (CTCs) are cancer cells that detach from the primary site and travel in the blood stream. A higher number of CTCs increases the risk of breast cancer metastasis, and it is inversely associated with the survival rates of patients with breast cancer. Although the numbers of CTCs are generally low and the majority of CTCs die in circulation, the survival of a few CTCs can seed the development of a tumor at a secondary location. An increasing number of studies demonstrate that CTCs undergo modification in response to the dynamic biophysical environment in the blood due in part to fluid shear stress. Fluid shear stress generates reactive oxygen species (ROS), triggers redox-sensitive cell signaling, and alters the function of intracellular organelles. In particular, the mitochondrion is an important target organelle in determining the metastatic phenotype of CTCs. In healthy cells, mitochondria produce adenosine triphosphate (ATP) via oxidative phosphorylation in the electron transport chain, and during oxidative phosphorylation, they produce physiological levels of ROS. Mitochondria also govern death mechanisms such as apoptosis and mitochondrial permeability transition pore opening to, in order eliminate unwanted or damaged cells. However, in cancer cells, mitochondria are dysregulated, causing aberrant energy metabolism, redox homeostasis, and cell death pathways that may favor cancer invasiveness. In this review, we discuss the influence of fluid shear stress on CTCs with an emphasis on breast cancer pathology, then discuss alterations of cellular mechanisms that may increase the metastatic potentials of CTCs.

Effects of Dietary or Supplementary Micronutrients on Sex Hormones and IGF-1 in Middle and Older Age: A Systematic Review and Meta-Analysis

Observational research suggests that micronutrients may be protective for sarcopenia, a key health issue during ageing, potentially via effects on hormone synthesis and metabolism. We aimed to carry out a systematic review of RCTs investigating effects of increasing dietary or supplemental micronutrient intake on sex hormones and IGF-1 in individuals aged 45 years or older. We searched MEDLINE, EMBASE and Cochrane databases for RCTs reporting the effects of different micronutrients (vitamins A, C, D, or E; carotenoids; iron; copper; zinc; magnesium; selenium; and potassium) on sex hormones or IGF-1. Of the 26 RCTs identified, nine examined effects of vitamin D, nine of multi-nutrients, four of carotenoids, two of selenium, one of zinc, and one of vitamin E. For IGF-1 increasing vitamin D (MD: −0.53 nmol/L, 95% CI: −1.58, 0.52), multi-nutrients (MD: 0.60 nmol/L, 95% CI −1.12 to 2.33) and carotenoids (MD −1.32 nmol/L; 95% CI −2.76 to 0.11) had no significant effect on circulating concentrations. No significant effects on sex hormones of other micronutrients were found, but data were very limited. All trials had significant methodological limitations making effects of micronutrient supplementation on sex hormones unclear. Further high quality RCTs with physiological doses of micronutrients in people with low baseline intakes or circulating concentrations, using robust methodology, are required to assess effects of supplementation adequately.

Retinol palmitate and ascorbic acid: Role in oncological prevention and therapy

Cancer development has been directly related to oxidative stress. During chemotherapy, some cancer patients use dietary antioxidants to avoid nutritional deficiencies due to cancer treatment. Among the antioxidants consumed, there are vitamins, including retinyl palmitate (PR) and ascorbic acid (AA), which have the capacity to reduce free radicals formation, protect cellular structures and maintain the cellular homeostasis. This systematic review evaluated the antioxidant and antitumor mechanisms of retinol palmitate (a derivative of vitamin A) and/or ascorbic acid (vitamin C) in cancer-related studies. Ninety-seven (97) indexed articles in the databases PubMed and Science Direct, published between 2013 and 2017, including 23 clinical studies (5 for every single compound while 13 in interaction) and 74 non-clinical studies (37 for retinol palmitate, 36 for ascorbic acid and 1 in interaction) were considered. Antioxidant and antitumor effects, with controversies over dosage and route of administration, were observed for the test compounds in their isolated form or associated in clinical studies. Prevention of cancer risks against oxidative damage was seen in lower doses of retinol palmitate and/or vitamin C. However, at high doses, they can generate reactive oxygen species, cytotoxicity and apoptosis in test systems. Non-clinical studies using cell lines have allowed understanding the mechanisms related to antioxidants and antitumor effects of the isolated compounds, however, studies on vitamin interactions, acting as antioxidants and/or antitumor are still rare and controversial. More studies, mainly related to modulation of antineoplastic drugs are needed for understanding the risks and benefits of their use during treatment in order to achieve effectiveness in cancer therapy and patient's quality of life.