Association Between BRCA Status and P53 Status in Breast Cancer: A Meta-Analysis

Advancements in targeting tumor suppressor genes (p53 and BRCA 1/2) in breast cancer therapy

Globally, among numerous cancer subtypes, breast cancer (BC) is one of the most prevalent forms of cancer affecting the female population. A female's family history significantly increases her risk of developing breast cancer. BC is caused by aberrant breast cells that proliferate and develop into tumors. It is estimated that 5-10% of breast carcinomas are inherited and involve genetic mutations that ensure the survival and prognosis of breast cancer cells. The most common genetic variations are responsible for hereditary breast cancer but are not limited to p53, BRCA1, and BRCA2. BRCA1 and BRCA2 are involved in genomic recombination, cell cycle monitoring, programmed cell death, and transcriptional regulation. When BRCA1 and 2 genetic variations are present in breast carcinoma, p53 irregularities become more prevalent. Both BRCA1/2 and p53 genes are involved in cell cycle monitoring. The present article discusses the current status of breast cancer research, spotlighting the tumor suppressor genes (BRCA1/2 and p53) along with structural activity relationship studies, FDA-approved drugs, and several therapy modalities for treating BC. Breast cancer drugs, accessible today in the market, have different side effects including anemia, pneumonitis, nausea, lethargy, and vomiting. Thus, the development of novel p53 and BRCA1/2 inhibitors with minimal possible side effects is crucial. We have covered compounds that have been examined subsequently (2020 onwards) in this overview which may be utilized as lead compounds. Further, we have covered mechanistic pathways to showcase the critical druggable targets and clinical and post-clinical drugs targeting them for their utility in BC.

Identification of modules and key genes associated with breast cancer subtypes through network analysis

Breast cancer is the most common malignancy in women around the world. Intratumor and intertumoral heterogeneity persist in mammary tumors. Therefore, the identification of biomarkers is essential for the treatment of this malignancy. This study analyzed 28,143 genes expressed in 49 breast cancer cell lines using a Weighted Gene Co-expression Network Analysis to determine specific target proteins for Basal A, Basal B, Luminal A, Luminal B, and HER2 ampl breast cancer subtypes. Sixty-five modules were identified, of which five were characterized as having a high correlation with breast cancer subtypes. Genes overexpressed in the tumor were found to participate in the following mechanisms: regulation of the apoptotic process, transcriptional regulation, angiogenesis, signaling, and cellular survival. In particular, we identified the following genes, considered as hubs: IFIT3, an inhibitor of viral and cellular processes; ETS1, a transcription factor involved in cell death and tumorigenesis; ENSG00000259723 lncRNA, expressed in cancers; AL033519.3, a hypothetical gene; and TMEM86A, important for regulating keratinocyte membrane properties, considered as a key in Basal A, Basal B, Luminal A, Luminal B, and HER2 ampl breast cancer subtypes, respectively. The modules and genes identified in this work can be used to identify possible biomarkers or therapeutic targets in different breast cancer subtypes.

Postpartum Breast Cancer and Survival in Women With Germline BRCA Pathogenic Variants

Importance

In young-onset breast cancer (YOBC), a diagnosis within 5 to 10 years of childbirth is associated with increased mortality. Women with germline BRCA1/2 pathogenic variants (PVs) are more likely to be diagnosed with BC at younger ages, but the impact of childbirth on mortality is unknown.

Objective

To determine whether time between most recent childbirth and BC diagnosis is associated with mortality among patients with YOBC and germline BRCA1/2 PVs.

Design, Setting, and Participants

This prospective cohort study included women with germline BRCA1/2 PVs diagnosed with stage I to III BC at age 45 years or younger between 1950 and 2021 in the United Kingdom, who were followed up until November 2021. Data were analyzed from December 3, 2021, to November 29, 2023.

Exposure

Time between most recent childbirth and subsequent BC diagnosis, with recent childbirth defined as 0 to less than 10 years, further delineated to 0 to less than 5 years and 5 to less than 10 years.

Main Outcomes and Measures

The primary outcome was all-cause mortality, censored at 20 years after YOBC diagnosis. Mortality of nulliparous women was compared with the recent post partum groups and the 10 or more years post partum group. Cox proportional hazards regression analyses were adjusted for age, tumor stage, and further stratified by tumor estrogen receptor (ER) and BRCA gene status.

Results

Among 903 women with BRCA PVs (mean [SD] age at diagnosis, 34.7 [6.1] years; mean [SD] follow-up, 10.8 [9.8] years), 419 received a BC diagnosis 0 to less than 10 years after childbirth, including 228 women diagnosed less than 5 years after childbirth and 191 women diagnosed 5 to less than 10 years after childbirth. Increased all-cause mortality was observed in women diagnosed within 5 to less than 10 years post partum (hazard ratio [HR], 1.56 [95% CI, 1.05-2.30]) compared with nulliparous women and women diagnosed 10 or more years after childbirth, suggesting a transient duration of postpartum risk. Risk of mortality was greater for women with ER-positive BC in the less than 5 years post partum group (HR, 2.35 [95% CI, 1.02-5.42]) and ER-negative BC in the 5 to less than 10 years post partum group (HR, 3.12 [95% CI, 1.22-7.97]) compared with the nulliparous group. Delineated by BRCA1 or BRCA2, mortality in the 5 to less than 10 years post partum group was significantly increased, but only for BRCA1 carriers (HR, 2.03 [95% CI, 1.15-3.58]).

Conclusions and Relevance

These findings suggest that YOBC with germline BRCA PVs was associated with increased risk for all-cause mortality if diagnosed within 10 years after last childbirth, with risk highest for ER-positive BC diagnosed less than 5 years post partum, and for ER-negative BC diagnosed 5 to less than 10 years post partum. BRCA1 carriers were at highest risk for poor prognosis when diagnosed at 5 to less than 10 years post partum. No such associations were observed for BRCA2 carriers. These results should inform genetic counseling, prevention, and treatment strategies for BRCA PV carriers.

Peptide Vaccines as Therapeutic and Prophylactic Agents for Female-Specific Cancers: The Current Landscape

Breast and gynecologic cancers are significant global threats to women's health and those living with the disease require lifelong physical, financial, and social support from their families, healthcare providers, and society as a whole. Cancer vaccines offer a promising means of inducing long-lasting immune response against the disease. Among various types of cancer vaccines available, peptide vaccines offer an effective strategy to elicit specific anti-tumor immune responses. Peptide vaccines have been developed based on tumor associated antigens (TAAs) and tumor specific neoantigens which can also be of viral origin. Molecular alterations in HER2 and non-HER2 genes are established to be involved in the pathogenesis of female-specific cancers and hence were exploited for the development of peptide vaccines against these diseases, most of which are in the latter stages of clinical trials. However, prophylactic vaccines for viral induced cancers, especially those against Human Papillomavirus (HPV) infection are well established. This review discusses therapeutic and prophylactic approaches for various types of female-specific cancers such as breast cancer and gynecologic cancers with special emphasis on peptide vaccines. We also present a pipeline for the design and evaluation of a multiepitope peptide vaccine that can be active against female-specific cancers.

Prevalence of TP53 gene Pro72Arg (rs1042522) single nucleotide polymorphism among Egyptian breast cancer patients

Background

The P53 protein has an essential role in several cellular processes, including DNA repair, apoptosis, and cell cycle arrest. The pathophysiology of many cancer types has frequently been linked to polymorphisms in the TP53 locus. Over 200 single nucleotide polymorphisms (SNPs) have been identified in TP53. However, Pro72Arg (rs1042522) at codon 72, shows contradictory results in terms of cancer risk. In this study, we aimed to determine if the Pro72Arg (rs1042522) SNP in the TP53 gene would be linked to breast cancer (BC) risk among Egyptian patients.

Materials and Methods

Genomic DNA was extracted from blood samples of 100 healthy volunteers and 100 breast cancer patients (50 familial and 50 non-familial). TP53 Genotyping was performed using tetra-primer amplification refractory mutation (Tetra-ARMS) PCR. Data were analyzed using SNPstat software.

Results

The prevalence of TP53 (Pro72Arg) rs1042522 genotypes carrying the high-risk allele [Pro/Arg (CG) and Arg/Arg (GG)] were significantly higher in BC patients compared to healthy volunteers and were associated with BC susceptibility (OR 0.2; [95% CI 0.11–0.38]; P = 0.0001). However, there was no statistical significant difference in the prevalence of TP53 (Pro72Arg) rs1042522 genotypes carrying the high-risk allele between familial and non-familial BC patients. In addition, there was no association between the prevalence of TP53 (Pro72Arg) rs1042522 genotypes carrying the high-risk allele and BC patients’ clinical and pathological characteristics including tumor size, tumor grade, lymph node status, presence of lymphovascular invasion, expression of ER, PR and Her-2 in both of familial and non-familial BC patients.

Conclusions

TP53 (Pro72Arg) rs1042522 is more prevalent among BC patients but not associated with disease progression.

A Review of Herbal Medicine-Based Phytochemical of Garcinia as Molecular Therapy for Breast Cancer

Data from globocan statistic in 2020 indicate that breast cancer has become highest incidence rate of cancer. Estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) are known immunohistochemistry (IHC) markers that mediate cell growth and survival signaling. Furthermore, regulator proteins, receptors, and their downstream signaling pathways have emerged as critical components in breast cancer formation and proliferation, and have become well-established therapeutic targets and the core focus of breast cancer therapy research. Garcinia is a big genus in the Clusiaceae family that contains a wide spectrum of biologically active metabolites for the chemical composition of their isolated fruits, stem barks, seeds, leaves, and roots, have resulted including polyisoprenylated benzophenones, polyphenols, bioflavonoids, xanthones, lactones, and triterpenes. This review article aimed to analyze the potential of Garcinia phytochemicals as a molecular therapy of breast cancer. The results showed that phytochemicals of Garcinia (i.e., α-mangostin, Cambogin, Gambogic Acid [GA], Garcinol, Griffipavixanthone, Friedolanostane triterpenoid, Hexane, Neobractatin, 7-Epiclusianone, xanthochymol - guttiferone E, and isoxanthochymol - cycloxanthochymol) have anticancer properties, including apoptosis, inhibition of proliferation, and metastasis. This review is important to provide information regarding phytochemicals of Garcinia as an alternative treatment for breast cancer patients. This article selected 28 article researches based on inclusion criteria with the keyword “Garcinia” and “Breast cancer”, in English, and available in full text and abstract searching on PubMed.

Peptide-Based Vaccines in Clinical Phases and New Potential Therapeutic Targets as a New Approach for Breast Cancer: A Review

Breast cancer is the leading cause of death in women from 20 to 59 years old. The conventional treatment includes surgery, chemotherapy, hormonal therapy, and immunotherapy. This immunotherapy is based on administering monoclonal therapeutic antibodies (passive) or vaccines (active) with therapeutic purposes. Several types of vaccines could be used as potential treatments for cancer, including whole-cell, DNA, RNA, and peptide-based vaccines. Peptides used to develop vaccines are derived from tumor-associated antigens or tumor-specific antigens, such as HER-2, MUC1, ErbB2, CEA, FRα, MAGE A1, A3, and A10, NY-ESO-1, among others. Peptide-based vaccines provide some advantages, such as low cost, purity of the antigen, and the induction of humoral and cellular immune response. In this review, we explore the different types of vaccines against breast cancer with a specific focus on the description of peptide-based vaccines, their composition, immune response induction, and the description of new potential therapeutic targets.

Cell-type-specific epigenomic variations associated with BRCA1 mutation in pre-cancer human breast tissues

BRCA1 germline mutation carriers are predisposed to breast cancers. Epigenomic regulations have been known to strongly interact with genetic variations and potentially mediate biochemical cascades involved in tumorigenesis. Due to the cell-type specificity of epigenomic features, profiling of individual cell types is critical for understanding the molecular events in various cellular compartments within complex breast tissue. Here, we produced cell-type-specific profiles of genome-wide histone modifications including H3K27ac and H3K4me3 in basal, luminal progenitor, mature luminal and stromal cells extracted from a small pilot cohort of pre-cancer BRCA1 mutation carriers (BRCA1^mut/+) and non-carriers (BRCA1^+/+), using a low-input ChIP-seq technology that we developed. We discovered that basal and stromal cells present the most extensive epigenomic differences between mutation carriers (BRCA1^mut/+) and non-carriers (BRCA1^+/+), while luminal progenitor and mature luminal cells are relatively unchanged with the mutation. Furthermore, the epigenomic changes in basal cells due to BRCA1 mutation appear to facilitate their transformation into luminal progenitor cells. Taken together, epigenomic regulation plays an important role in the case of BRCA1 mutation for shaping the molecular landscape that facilitates tumorigenesis.

Eco-Friendly Synthesis of MnO2 Nanorods Using Gmelina arborea Fruit Extract and Its Anticancer Potency Against MCF-7 Breast Cancer Cell Line

Introduction

Cancer disease is known due to its unregulated proliferation of cells that have evolved from the body’s regular cells. The disease develops as a result of epigenetic and genetic modifications, tumor suppressor gene inactivation, and oncogene activation. The present work describes an environmentally benign approach for the synthesis of manganese oxide nanoparticles (MnO₂ NPs) using Gmelina arborea fruit extract (GAE) in an aqueous medium.

Methods

The study evaluated the formation of MnO₂ NPs and their anticancer efficacy against MCF-7 breast cancer cell line.

Results

The formation of MnO₂ NPs was confirmed through powder X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HR-TEM). The crystalline nature of as-prepared MnO₂ NPs was evident from XRD pattern. The morphology of the material was studied using SEM analysis, which suggested a rod-like nature with an average diameter of 50 nm. Further, the TEM and HR-TEM images confirmed the rod shape of the as-prepared MnO2 NPs with an interplanar distance of 0.271 nm. In addition, the concentric rings from selected area electron diffraction (SAED) analysis show the crystalline nature of the as-prepared material, which further supports the obtained XRD pattern. The anticancer efficacy of MnO₂ NPs was evaluated against MCF-7 breast cancer cell line, which showed up to 96% inhibition of the cells at 400 µg/mL concentration.

Conclusion

Bio-conjugation of MnO₂ NPs can provide enough scope for the therapeutic use of Gmelina arborea, assuming appropriate mechanistic evaluations are conducted.

The suppressive role of nanoencapsulated chia oil against DMBA-induced breast cancer through oxidative stress repression and tumor genes expression modulation in rats

BACKGROUND

Chia oil is high in omega-3 fatty acids, which have been linked to a lower risk of many diseases, including cancer. Oil encapsulation is a method that holds promise for maintaining oil content while enhancing solubility and stability. The purpose of this study is to prepare nanoencapsulated Chia oil and investigate its suppressive effects on rat chemically induced breast cancer.

METHODS

The oil was extracted from commercial Chia seeds and their fatty acids were analyzed using Gas Chromatography-mass spectrometry (GC/MS). Sodium alginate was used as a loading agent to create the Chia oil nanocapsules. The DPPH assay was used to assess the oil nanocapsules' capacity to scavenge free radicals. Breast cancer induction was done by single dose subcutaneously administration of 80 mg/kg dimethylbenz (a) anthracene (DMBA). Models of breast cancer were given Chia oil nanocapsules orally for one month at doses of 100 and 200 mg/kg. Through measuring intracellular reactive oxygen species (ROS) and protein carbonyl, assessing the gene expression of tumor suppressor genes (BRCA 1 & 2, TP53), and conducting histopathological analysis, the suppressive effect of Chia oil nanocapsules was examined.

RESULTS

The increase in ROS and PC levels brought on by DMBA was significantly decreased by the administration of Chia oil nanocapsules. In tumor tissue from rats given Chia oil nanocapsules, the mRNA expression levels of BRCA1, BRCA2, and TP53 were controlled Histopathological analysis clarified that the tissue architecture of breast tumors was improved by nanocapsules management.

CONCLUSIONS

These findings demonstrate the ability of Chia oil nanocapsules to inhibit cancer cells in the rat breast.

TP53 Co-Mutational Features and NGS-Calibrated Immunohistochemistry Threshold in Gastric Cancer

Purpose

TP53 is the most frequently mutated gene in gastric cancer and it can be potentially used for gastric cancer diagnosis and screening. However, standardized clinical approaches that could accurately and cost-effectively detect TP53 mutations in gastric cancer are largely lagged behind.

Patients and Methods

We conducted next-generation sequencing (NGS) analysis of 425 cancer-related genes in 42 gastric cancer patients in our cohort. A 1313-patient cohort derived from the cBioPortal database was used for validation. We performed immunohistochemistry (IHC) staining with four commonly used p53 antibodies, and the NGS results were used as the gold standard to optimize the IHC threshold for each antibody.

Results

By NGS analysis, we found that around 80% of gastric cancer patients in our cohort harbored TP53 alterations. Genetic alterations of BRCA1/2 or KMT2B were mostly exclusive with TP53 mutations, so were the MSI status or low grade of tumors. These results were further validated using the data from cBioPortal. We then used the NGS-derived TP53 status to optimize four commonly used IHC antibodies for detecting TP53 mutations. We showed that all antibodies could achieve more than 93% accuracy when proper IHC positivity thresholds were used, especially for the SP5 antibody that could reach 100% sensitivity and specificity with the 20% threshold.

Conclusion

Our results indicated that exclusivity between TP53 and BRCA mutations could be potentially used as a cost-effective way to predict BRCA status. Also, setting proper IHC thresholds for each specific antibody is critical to accurately detect TP53 mutations and facilitate disease diagnosis.

BRCA Mutational Status is a Promising Predictive Biomarker for Platinum- based Chemotherapy in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) can be distinguished from other breast malignancies by the lack of expression of estrogen receptors (ER), progesterone receptors (PR) as well as human epidermal growth factor receptor 2 (HER2). TNBC is associated with adverse clinical outcomes and high risk of metastasis. Currently, several clinical and translational reports are focusing on developing targeted therapies for this aggressive cancer. In addition to approved targeted drugs such as poly(ADP-ribose) polymerase inhibitors (PARPi) and immune-checkpoint inhibitors, platinum-based chemotherapy is still a cornerstone therapeutic option in TNBC. However, despite the observed improved outcomes with platinum- based chemotherapy in TNBC, there is still a large proportion of patients who do not respond to this treatment, hence, the need for predictive biomarkers to stratify TNBC patients and therefore, avoiding unwanted toxicities of these agents. With the emergence of genetic testing, several recent studies suggested mutations in breast cancer susceptibility gene (BRCA) in TNBC patients as important predictors of outcomes. These mutations alter the homologous recombination repair (HRR) mechanisms leading to genomic instability. Consequently, sensitivity to platinum-based treatments in this subpopulation of TNBC patients may be explained by cell death enhanced by deoxyribonucleic acid (DNA) damage induced by these potent anticancer drugs. Through this paper, we review several recent studies on this topic to better understand the mechanisms and discuss the potential of BRCA mutational status as a predictive biomarker of platinum-based chemotherapy in TNBC.

Myricetin Exerts its Apoptotic Effects on MCF-7 Breast Cancer Cells through Evoking the BRCA1-GADD45 Pathway

OBJECTIVE

Myricetin is a polyphenol flavonoid with nutraceutical values which is abundantly found as the main ingredient of various foods and beverages. It has been reported that the function of myricetin is to trigger apoptosis in several types of cancers. The present study intended to investigate the apoptotic effects of myricetin on MCF-7 breast cancer cells and to assess its possible mechanisms of action.

MATERIALS AND METHODS

MCF-7 breast cancer cells were assigned to four groups: Control (cells in normal condition); myricetin (cells treated with the IC50 dosage of myricetin) in three different incubation times (24, 48, and 72 h). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, annexin V assay, flow cytometry, real-time polymerase chain reaction (PCR), and caspase-3 assay were used to estimate the apoptosis function of myricetin in breast cancer.

RESULTS

The expression levels of apoptosis-related genes caspase-3, caspase-8, caspase-9, and the BAX /Bcl-2 ratio as well as the expression of p53, BRCA1, GADD45 genes were significantly increased following the treatment of MCF-7 breast cancer cells with myricetin. The annexin V assay demonstrated the significant expression of annexin which was also detected by flow cytometry.

CONCLUSION

Myricetin efficiently induces apoptosis in MCF-7 breast cancer cells by evoking both extrinsic and intrinsic apoptotic pathways. Myricetin may exert its apoptotic effects on MCF-7 cells by inducing the BRCA1- GADD45 pathway.
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Association Between BRCA Status and Triple-Negative Breast Cancer: A Meta-Analysis

Triple-negative breast cancer (TNBC) is a subtype of aggressive breast cancer and characterized by a lack of the expression of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. BRCA genes are tumor-suppressor genes that are involved in DNA damage repair and mutations of BRCA genes may increase the risk of developing breast cancer and/or ovarian cancer due to defective DNA repair mechanisms. However, the relationship between BRCA status and TNBC needs to be further investigated and validated. The aim of this meta-analysis was to evaluate the association between BRCA status and TNBC. We systematically searched the electronic databases of MEDLINE (PubMed), Embase, and Cochrane Library to identify relevant publications from April, 1959 to November, 2017. The data from the studies were examined by a meta-analysis using STATA software to calculate the odds ratio (OR) with 95% confidence interval (CI) by fixed-effect and random-effect models. We identified 16 qualified studies from 527 publications with 46,870 breast cancer patients including 868 BRCA1 mutations (BRCA1^Mut) carriers, 739 BRCA2 mutations (BRCA2^Mut) carriers, and 45,263 non-carriers. The results showed that breast cancer patients with BRCA1^Mut carriers were more likely to have TNBC than those of BRCA2^Mut carriers (OR: 3.292; 95% CI: 2.773–3.909) or non-carriers (OR: 8.889; 95% CI: 6.925–11.410). Furthermore, high expression of nuclear grade and large tumor burden (>2 cm) were significantly more common in breast cancer patients with BRCA1^Mut carriers than those of BRCA2^Mut carriers (OR: 2.663; 95% CI: 1.731–4.097; P = 0.211) or non-carriers (OR: 1.577; 95% CI: 1.067–2.331; P = 0.157). The data suggest that breast cancer patients with BRCA1^Mut are more likely to have TNBC, high nuclear grade, and larger tumor burden.