Influence of CYP19A1 gene expression levels in women with breast cancer: a systematic review of the literature.

Breast cancer is the most frequently diagnosed malignant neoplasm in women and is considered a multifactorial disease of unknown etiology. One of the major risk factors is genetic alteration. Changes in CYP19A1 gene expression levels have been associated with increased risk and increased aggressiveness of breast cancer. Increased CYP19A1 gene expression and/or aromatase activity are among the major regulatory events for intratumoral production of estrogens in breast malignant tissues. This systematic review aimed to investigate the influence of CYP19A1 gene expression levels in women with breast cancer. The research was carried out using the PubMed, Scopus, and Web of Science databases. Searches were conducted between February 2 and May 15, 2019. Inclusion criteria were studies published between 2009 and 2019, English language publications, and human studies addressing the gene expression of CYP19A1 in breast cancer. A total of 6.068 studies were identified through PubMed (n=773), Scopus (n=2,927), and the Web of Science (n=2,368). After selecting and applying the inclusion and exclusion criteria, six articles were included in this systematic review. This systematic review provides evidence that increased or decreased levels of CYP19A1 gene expression may be related to pathological clinical factors of disease, MFS, OS, DFS, WATi, markers of metabolic function, concentrations of E1, FSH, and in the use of multiple exons 1 of the CYP19A1 gene in breast cancer.

Influence of CYP19A1 gene expression levels in women with breast cancer: a systematic review of the literature

Breast cancer is the most frequently diagnosed malignant neoplasm in women and is considered a multifactorial disease of unknown etiology. One of the major risk factors is genetic alteration. Changes in CYP19A1 gene expression levels have been associated with increased risk and increased aggressiveness of breast cancer. Increased CYP19A1 gene expression and/or aromatase activity are among the major regulatory events for intratumoral production of estrogens in breast malignant tissues. This systematic review aimed to investigate the influence of CYP19A1 gene expression levels in women with breast cancer. The research was carried out using the PubMed, Scopus, and Web of Science databases. Searches were conducted between February 2 and May 15, 2019. Inclusion criteria were studies published between 2009 and 2019, English language publications, and human studies addressing the gene expression of CYP19A1 in breast cancer. A total of 6.068 studies were identified through PubMed (n=773), Scopus (n=2,927), and the Web of Science (n=2,368). After selecting and applying the inclusion and exclusion criteria, six articles were included in this systematic review. This systematic review provides evidence that increased or decreased levels of CYP19A1 gene expression may be related to pathological clinical factors of disease, MFS, OS, DFS, WATi, markers of metabolic function, concentrations of E1, FSH, and in the use of multiple exons 1 of the CYP19A1 gene in breast cancer.

Assessment of IGF-1 expression in the peripheral blood of women with recurrent breast cancer.

Breast cancer is the most common malignancy affecting women worldwide. The insulin-like growth factor 1 (IGF-1) gene encodes a protein responsible for a wide variety of physiological processes, including differentiation and cell proliferation. Despite several studies on tumor tissues, no study has evaluated IGF-1 expression in the peripheral blood of women with recurrent breast cancer.In this cross-sectional study, IGF-1 expression in the peripheral blood of 146 women with breast cancer treated approximately 5 years ago was quantified by quantitative reverse transcription polymerase chain. The women were divided into 2 groups: non-recurrence (n = 85) and recurrence (n = 61). Statistical analysis of the data was performed using ANOVA, Mann-Whitney, and Chi-squared tests (P < .05).The results showed no significant difference in IGF-1 expression between the non-recurrence and recurrence groups (P = .988). In the subgroups of patients with lymph node involvement, no statistically significant difference was observed in IGF-1 expression between women with recurrence and those non-recurrence (P = .113). In patients without lymph node metastases, IGF-1 messenger ribonucleic acid (mRNA) expression levels were significantly higher in the non-recurrence group than in the recurrence group (P = .019). Furthermore, using the median IGF-1 mRNA expression as the cutoff point, it was obtained a statistically significant difference in tumor histological grade among women with recurrent breast cancer (P = .042).These data showed significantly higher IGF-1 expression in women without lymph node metastases in the non-recurrence group compared with the recurrence group. In addition, a significant difference was observed in median IGF-1 mRNA expression in relation to tumor histological grade in women with recurrent breast cancer.

CYP19A1 gene expression in the peripheral blood of Brazilian women with breast cancer relapse.

BACKGROUND: The CYP19A1 gene, which encodes the enzyme responsible for androgen aromatization into estrogens, may play an important role in breast cancer aggressiveness. However, no study has evaluated CYP19A1 gene expression in the peripheral blood of women with relapsed breast cancer. METHODS: In this cross-sectional study, CYP19A1 gene expression was quantified by RT-PCR in the peripheral blood of 146 women with breast cancer who were first divided into two groups according to the expression of CYP19A1 (low and high); each group had 73 patients. Subsequently, women were divided into two groups: those without recurrence (control, n = 85) and those with recurrence (study, n = 61). Statistical analysis of the data was performed using ANOVA, the Mann-Whitney, Chi-square or Fisher's exact test (p <  0.05). RESULTS: There were no significant differences between the relative expression of CYP19A1 mRNA in the low expression group and the high expression group according to the variables studied. There were no significant differences in CYP19A1 gene expression in the study and control groups (p = 0.8461). In the relapse group, CYP19A1 gene expression was significantly higher in the hybrid luminal subtype than in the triple-negative subtype (p = 0.0321), whereas it was significantly lower in HER2-negative cases than in HER2-positive cases (p <  0.0376). Women with locoregional recurrence showed higher expression than women with distant recurrence (p <  0.0001). CONCLUSIONS: The present study found no significant differences between women with high and low expression of the CYP19A1 gene mRNA or between those in the study group and the control group. However, in women with recurrence, there was increased expression of CYP19A1 mRNA in those who had the luminal hybrid subtype and locoregional relapse and decreased expression in those negative for HER2.

Effects of anastrozole on Ki-67 antigen expression in the vaginal epithelium of female rats in persistent estrus.

OBJECTIVES: Aromatase inhibitors are the first-choice drugs for the treatment of hormone sensitive breast cancer. However, in addition to the scarcity of studies, there are controversies about their effects on vaginal epithelial cell proliferation in rats, especially those in persistent estrus. METHODS: To investigate vaginal epithelial cell proliferation by Ki-67 antigen expression, persistent estrus was induced in 42 randomly selected rats. These rats were randomly divided into 2 groups: group I (control, n=21), which received 0.1 mL of propylene glycol (vehicle) daily, and group II (experimental, n=21), which received 0.5 mg/kg or 0.125 mg/day of anastrozole diluted with 0.1 mL of propylene glycol. RESULTS: Light microscopy showed a higher concentration of cells with brown Ki-67 stained nuclei in the control compared to the experimental group. The mean percentage of Ki-67 stained nuclei per 500 cells in the vaginal epithelium was 68.64±2.64 and 30.46±2.00 [mean±standard error of the mean (SEM)] in the control and experimental groups, respectively (p<0.003). CONCLUSION: This study showed that anastrozole, at the dose and treatment duration selected, significantly decreased cell proliferation in the vaginal mucosa of the rats in persistent estrus.

Effects of anastrozole on Ki-67 antigen expression in the vaginal epithelium of female rats in persistent estrus

OBJECTIVES: Aromatase inhibitors are the first-choice drugs for the treatment of hormone sensitive breast cancer. However, in addition to the scarcity of studies, there are controversies about their effects on vaginal epithelial cell proliferation in rats, especially those in persistent estrus. METHODS: To investigate vaginal epithelial cell proliferation by Ki-67 antigen expression, persistent estrus was induced in 42 randomly selected rats. These rats were randomly divided into 2 groups: group I (control, n=21), which received 0.1 mL of propylene glycol (vehicle) daily, and group II (experimental, n=21), which received 0.5 mg/kg or 0.125 mg/day of anastrozole diluted with 0.1 mL of propylene glycol. RESULTS: Light microscopy showed a higher concentration of cells with brown Ki-67 stained nuclei in the control compared to the experimental group. The mean percentage of Ki-67 stained nuclei per 500 cells in the vaginal epithelium was 68.64±2.64 and 30.46±2.00 [mean±standard error of the mean (SEM)] in the control and experimental groups, respectively (p<0.003). CONCLUSION: This study showed that anastrozole, at the dose and treatment duration selected, significantly decreased cell proliferation in the vaginal mucosa of the rats in persistent estrus.

Review of Polymorphism of the Calcium-Sensing Receptor Gene and Breast Cancer Risk.

Polymorphism of the calcium-sensing receptor gene (CaSR or CaR) has been associated with an increased risk for breast cancer. This receptor plays an important role in calcium homeostasis, and has also been detected in several tissues that are unrelated to calcium metabolism, such as the skin, brain, and breast. The calcium-sensing receptor on cellular level, it regulates cell differentiation, proliferation, cell death, and gene expression. In breast cancer cells, CaSR seems to stimulate secretion of the parathyroid hormone-related protein (PTHrP), which stimulates cellular proliferation. Likewise, some studies have supported not only an association between calcium receptor gene polymorphism and breast cancer risk, but also a higher aggressiveness and unfavorable outcomes in breast cancer, which led us to make a survey in Pubmed on the subject in the last 10 years. Thus, in the literature there is a paucity of studies on the subject and the aim of this review was to show the role of calcium-sensing receptor and its association with breast cancer risk.

Use of anastrozole in the chemoprevention and treatment of breast cancer: A literature review.

Aromatase inhibitors have emerged as an alternative endocrine therapy for the treatment of hormone sensitive breast cancer in postmenopausal women. The use of third-generation inhibitors represented by exemestane, letrozol and anastrozole is currently indicated. Anastrozole is a nonsteroidal compound and a potent selective inhibitor of the aromatase enzyme. Although a few studies have shown that its pharmacodynamic and pharmacokinetic properties may be affected by interindividual variability, this drug has been recently used in all configurations of breast cancer treatment. In metastatic disease, it is currently considered the first-line treatment for postmenopausal women with estrogen receptor-positive breast tumors. Anastrozole has shown promising results in the adjuvant treatment of early-stage breast cancer in postmenopausal women. It has also achieved interesting results in the chemoprevention of the disease. Therefore, due to the importance of anastrozole both for endocrine treatment and chemoprevention of hormone-sensitive breast cancer in postmenopausal women, we proposed the current literature review in the SciELO and PubMed database of articles published in the last 10 years.

Use of anastrozole in the chemoprevention and treatment of breast cancer: A literature review / Uso do anastrozol na quimioprevenção e no tratamento do câncer de mama: uma revisão da literatura

Summary Aromatase inhibitors have emerged as an alternative endocrine therapy for the treatment of hormone sensitive breast cancer in postmenopausal women. The use of third-generation inhibitors represented by exemestane, letrozol and anastrozole is currently indicated. Anastrozole is a nonsteroidal compound and a potent selective inhibitor of the aromatase enzyme. Although a few studies have shown that its pharmacodynamic and pharmacokinetic properties may be affected by interindividual variability, this drug has been recently used in all configurations of breast cancer treatment. In metastatic disease, it is currently considered the first-line treatment for postmenopausal women with estrogen receptor-positive breast tumors. Anastrozole has shown promising results in the adjuvant treatment of early-stage breast cancer in postmenopausal women. It has also achieved interesting results in the chemoprevention of the disease. Therefore, due to the importance of anastrozole both for endocrine treatment and chemoprevention of hormone-sensitive breast cancer in postmenopausal women, we proposed the current literature review in the SciELO and PubMed database of articles published in the last 10 years.

Resumo Os inibidores de aromatase têm emergido como uma endocrinoterapia alternativa para o tratamento de câncer de mama sensível a hormônios em mulheres pós-menopáusicas. A utilização de inibidores de terceira geração, representados por exemestano, letrozol e anastrozol, é atualmente indicada. Anastrozol é um composto não esteroide e um inibidor potente e seletivo da enzima aromatase. Embora alguns estudos tenham demonstrado que as suas propriedades farmacodinâmicas e farmacocinéticas podem ser afetadas pela variabilidade interindividual, esse fármaco tem sido recentemente utilizado em todas as configurações de tratamento do câncer de mama. Na doença metastática, é atualmente considerado o tratamento de primeira linha em mulheres pós-menopáusicas com tumores de mama e receptor de estrogênio positivo. O anastrozol tem mostrado resultados promissores no tratamento adjuvante do câncer de mama em estágio inicial em mulheres na pós-menopausa. Ele também conseguiu resultados interessantes na quimioprevenção da doença. Portanto, em virtude da importância do anastrozol tanto no tratamento endócrino quanto na quimioprevenção do câncer de mama hormoniossensível em mulheres na pós-menopausa, propusemos a atual revisão da literatura na base de dados SciELO e PubMed de artigos publicados nos últimos 10 anos.

Ki-67 antigen expression in the mammary epithelium of female rats in persistent estrus treated with anastrozole.

OBJECTIVES: To evaluate Ki-67 antigen expression in mammary epithelium of female rats in persistent estrus treated with anastrozole. MATERIALS AND METHODS: Twenty-eight Wistar-Hanover female rats in persistent estrus induced by subcutaneous injection of 1.25 mg of testosterone propionate in the second day of life were randomly divided into two groups, control and experimental, with 14 animals each. The animals of control group received only the vehicle (propyleneglycol) and the animals of group experimental received 0.125 mg daily of anastrozole by gavage during 28 days. After 28 days of treatment, all animals were sacrificed and the first pair of abdominal-inguinal mammary glands was removed and fixed in 10% buffered formalin to investigate Ki-67 antigen expression by immunohistochemistry. RESULTS: The mean percentage of Ki-67-stained nuclei per 500 cells in the mammary epithelium was 76.97 ± 0.76 and 14.44 ± 2.02 [mean ± standard error of the mean (SEM)] in the control and experimental groups, respectively (p < 0.0001). CONCLUSIONS: Anastrozole treatment significantly reduced Ki-67 expression in the mammary epithelium of rats in persistent estrus.

Insulin-like Growth Factor 1 gene polymorphism and breast cancer risk.

Insulin-like Growth Factor-1 (IGF-1) gene polymorphism has been associated with an increased risk for breast cancer. IGF-1 is a key regulator of proliferation, cell differentiation and apoptosis. It has important mitogenic and anti-apoptotic activities in normal cells and in breast cancer cells, acting synergistically with estrogen to increase neoplastic cell proliferation. This review aims to present the recent finds of IGF-1 gene polymorphism and its relationship with the risk of breast cancer through following the polymorphic dinucleotide repeat cytosine-adenine (CA) and single nucleotide polymorphisms (SNPs) by searching in the PubMed database publications focused studies published from 2010 to 2015 related to IGF-1 gene polymorphism and breast cancer risk. A growing number of studies support an association between IGF-1 gene polymorphism and breast cancer risk with conflicting results, nevertheless elucidation of the patterns of IGF-1 gene expression may permit characterization of women at high-risk for breast cancer, as well as the development of strategies for early diagnosis and efficient treatment against the disease.

Expression of estrogen and progesterone receptors in astrocytomas: a literature review.

Gliomas are the most common type of primary central nervous system neoplasm. Astrocytomas are the most prevalent type of glioma and these tumors may be influenced by sex steroid hormones. A literature review for the presence of estrogen and progesterone receptors in astrocytomas was conducted in the PubMed database using the following MeSH terms: "estrogen receptor beta" OR "estrogen receptor alpha" OR "estrogen receptor antagonists" OR "progesterone receptors" OR "astrocytoma" OR "glioma" OR "glioblastoma". Among the 111 articles identified, 13 studies met our inclusion criteria. The majority of reports showed the presence of estrogen and progesterone receptors in astrocytomas. Overall, higher tumor grades were associated with decreased estrogen receptor expression and increased progesterone receptor expression.

Expression of estrogen and progesterone receptors in astrocytomas: a literature review

Gliomas are the most common type of primary central nervous system neoplasm. Astrocytomas are the most prevalent type of glioma and these tumors may be influenced by sex steroid hormones. A literature review for the presence of estrogen and progesterone receptors in astrocytomas was conducted in the PubMed database using the following MeSH terms: “estrogen receptor beta” OR “estrogen receptor alpha” OR “estrogen receptor antagonists” OR “progesterone receptors” OR “astrocytoma” OR “glioma” OR “glioblastoma”. Among the 111 articles identified, 13 studies met our inclusion criteria. The majority of reports showed the presence of estrogen and progesterone receptors in astrocytomas. Overall, higher tumor grades were associated with decreased estrogen receptor expression and increased progesterone receptor expression.