Human Epidermal Growth Factor Receptor-2 gene polymorphism and breast cancer risk in women from the Northeastern region of Brazil

OBJECTIVES: In the Human Epidermal Growth Factor Receptor-2 (HER2) rs1136201 variant, the presence of the G allele may promote cellular alterations and increase breast cancer risk, in addition to enhanced cellular proliferation, tumor aggressiveness, and metastases. The aim of this study was to investigate the presence of the single-nucleotide polymorphism (SNP) variant, rs1136201, within the HER2 gene in women from the Northeastern region of Brazil and breast cancer risk. METHODS: The study included 140 women who were divided into two groups, case (breast cancer) and control (without breast cancer), with 70 women in each group. Peripheral blood of each woman was drawn for the study of genomic Deoxyribonucleic acid (DNA) extracted from leukocytes using the genotyping technique by real-time polymerase chain reaction. RESULTS: The GG genotype occurred in 1 woman in both groups (1.4%) (p=0.32), while the AG genotype occurred in 19 (27.2%) and 13 (18.6%) women in the case and control (p=1.00) groups, respectively. No statistically significant difference in GG and AG genotypes was observed between the case and control groups in premenopausal women (p=1.00). Furthermore, no significant difference in genotypes was observed between the groups, among postmenopausal women (p=0.14). CONCLUSION: In this study, the HER2 rs1136201 polymorphism did not show any statistically significant association with breast cancer, both in premenopausal and postmenopausal women. Nevertheless, further studies with a larger sample size should be performed to assess the association of HER2 polymorphism with breast cancer risk in women from the Northeastern region of Brazil.

Inhibition of Mmp-9 Expression through Nf-Kβ by Natural Compounds as a Possible Therapeutic Adjuvant Strategy in Breast Cancer: A Systematic Review

MMP-9 expression may be induced at the transcriptional level in response to different agents. Due to its fundamental role in cancer progression, the control of MMP expression, especially MMP-9, is the possible target of future adjuvant therapies that seek to reduce metastases and angiogenesis in women with breast cancer. Therefore, the aim of this study was to search in the literature available evidences of extracts/or natural compounds that have potential therapeutic capacity to inhibit MMP-9 expression. Extracts and/or natural compounds identified in this review play a significant role in the inhibition of MMP-9 expression via NF-kβ, and may act on the prevention of metastases from primary breast tumors. The majority of the studies found have shown that natural products are capable of suppressing migration and invasion of breast cancer cells, thus inhibiting the formation of in vitro metastases. Further studies are warranted to understand the potential mechanisms of breast cancer metastasis from signaling cascades intrinsic to the tumor. Moreover, the NF-kβ, followed by Mitogen Activated Protein Kinases / Activator protein 1 (MAPK / AP-1) were the major pathways affected by the extracts and / or compounds studied. These pathways are directly linked to MMP-9 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.