Hormone Receptors and Human Epidermal Growth Factor (HER2) Expression in Fine-Needle Aspirates from Metastatic Breast Carcinoma - Role in Patient Management

Epidermal growth factor receptor mutations in breast Cancer: Therapeutic challenges and way forward

Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase (RTK) that is upregulated in aggressive triple-negative breast cancer (TNBC). Ligands such as EGF, TGF-α, epigen, and amphiregulin activate the auto-phosphorylation activity of tyrosine residues on EGFR, which regulates the growth, proliferation, adhesion, migration, and survival of cancer cells. Our prior studies depicted that inhibition of EGFR modulates the chemosensitivity in breast cancer stem cells and, thus, serves as a potent therapeutic target in breast cancer. Small-molecule tyrosine kinase inhibitors (TKIs) and monoclonal antibodies (mAbs) specifically targeting EGFR have been clinically approved for breast cancer treatment. However, intrinsic and acquired resistance generated due to EGFR mutations limits the applications of designed EGFR-TKIs in breast cancer patients. This review highlights the therapeutic approaches, and the challenges encountered in targeting EGFR-specific mutations. It suggests the need to develop more advanced higher-generation inhibitors for use in combinatorial therapy along with chemo-or-immune therapeutics in clinics as a breast cancer treatment strategy against relapse of the disease.

Small intestinal metastasis from primary breast cancer: a case report and review of literature

Small intestinal metastasis from primary breast cancer remains a rare clinical occurrence. Despite extensive research into its clinicopathological features and treatment options, the specific pathogenesis and optimal management strategies remain incompletely understood. This case report presents a patient with breast cancer that metastasized to the small intestine. The primary breast tumor was diagnosed as classic invasive lobular carcinoma. Subsequent surgical intervention successfully addressed the intestinal obstruction and confirmed the metastatic origin of the small intestinal tumor. Interestingly, the metastatic lesions exhibited features suggestive of pleomorphic lobular carcinoma. A PET-CT scan was performed to evaluate the distant metastasis status of this patient. Notably, hormonal receptor status shifted from positive to negative, while HER2 expression changed from negative to low between the primary tumor and metastatic lesions. The presence of an undiagnosed pleomorphic component in the primary tumor might explain the disease's progressive nature. In this case, systemic treatment with trastuzumab deruxtecan yielded favorable therapeutic outcomes. Overall, our findings suggest that re-evaluation of receptor status in breast cancer metastases is crucial for tailoring treatment strategies. Furthermore, a combination of palliative resection of small intestinal metastases and targeted therapy for HER2-low breast cancer may potentially improve survival.

Epidermal growth factor receptor inhibition potentiates chemotherapeutics-mediated sensitization of metastatic breast cancer stem cells

BACKGROUND

Metastasis has been a cause of the poor prognosis and cancer relapse of triple-negative breast cancer (TNBC) patients. The metastatic nature of TNBC is contributed by the breast cancer stem cells (CSCs) which have been implicated in tumorigenesis. Higher expression of epidermal growth factor receptor (EGFR) in breast CSCs has been used as a molecular target for breast cancer therapeutics. Thus, it necessitates the design and generation of efficacious EGFR inhibitors to target the downstream signaling associated with the cellular proliferation and tumorigenesis of breast cancer.

AIM

To generate efficacious EGFR inhibitors that can potentiate the chemotherapeutic-mediated mitigation of breast cancer tumorigenesis.

METHODS AND RESULTS

We identified small molecule EGFR inhibitors using molecular docking studies. In-vitro screening of the compounds was undertaken to identify the cytotoxicity profile of the small-molecule EGFR inhibitors followed by evaluation of the non-cytotoxic compounds in modulating the doxorubicin-induced migration, in-vitro tumorigenesis potential, and their effect on the pro-apoptotic genes' and protein markers' expression in TNBC cells. Compound 1e potentiated the doxorubicin-mediated inhibitory effect on proliferation, migration, in-vitro tumorigenesis capacity, and induction of apoptosis in MDA-MB-231 cells, and in the sorted CD24+-breast cancer cells and CD24-/CD44+-breast CSC populations. Orthotopic xenotransplantation of the breast CSCs-induced tumors in C57BL/6J mice was significantly inhibited by the low dose of Doxorubicin in the presence of compound 1e as depicted by molecular and immunohistochemical analysis.

CONCLUSION

Thus, the study suggests that EGFR inhibition-mediated sensitization of the aggressive and metastatic breast CSCs in TNBCs toward chemotherapeutics may reduce the relapse of the disease.

Association of HOTAIR gene rs920778 (C > T) and rs4759314 (A > G) polymorphism with breast cancer in Egyptian women

BACKGROUND

Hox transcript antisense RNA (HOTAIR) is considered an oncogene associated with the initiation and progression of many malignancies. Previous studies have examined the connection between HOTAIR SNPs rs4759314 and rs920778 for breast cancer (BC), getting variable results in multiple ethnicities. Therefore, this study was designed to evaluate the connection between these two SNPs and disease vulnerability, clinic-laboratory, and hormonal parameters, featuring status associations with the BC risk in an Egyptian woman sample.

METHODS AND RESULTS

In this case-control study, DNA was taken from the blood of 100 BC patients and 100 unrelated healthy Egyptian females. The characterization of rs4759314 was genotyped using the T-ARMS-PCR method and rs920778 using the SNP-RFLP technique for all participants. The frequency of the rs4759314 A > G variation revealed a statistically significant increase in BC risk with dominant (p = 0.013, OR = 1.592, 95% Cl = 1.105-2.293), co-dominant (p = 0.006, OR = 2.314, 95%Cl = 1.278-4.191) and overdominant (p = 0.002, OR = 2.571, 95% Cl = 1.430-4.624) genetic models. On the other hand, the rs920778 C > T polymorphism was not significantly associated with BC. ER/PR positivity with HER2 negativity was significantly associated with the AA genotype compared to the AG genotype. Otherwise, no significant associations between the two SNPs and clinical stage or hormonal features could be found. In conclusion, the rs4759314 A > G SNP in the HOTAIR gene is strongly associated with BC, which might warrant its determination among affected families for prevention and early treatment.

Novel Insights into Circular RNAs in Metastasis in Breast Cancer: An Update

Circular RNAs (circRNAs) are single-stranded closed non-coding RNA molecules that are aberrantly expressed and produce tumor-specific gene signatures in human cancers. They exert biological functions by acting as transcriptional regulators, microRNA sponges, and protein scaffolds, regulating the formation of protein-RNA complexes and, ultimately, regulating gene expression. Triple-negative breast cancer (TNBC) is one of the most aggressive cancers of the mammary gland and has a poor prognosis. Studies of circRNAs in TNBC are limited but have demonstrated these molecules' pivotal roles in cell proliferation, invasion, metastasis, and resistance to chemo/radiotherapy, suggesting that they could be potential prognostic biomarkers and novel therapeutic targets. Here, we reviewed the status of actual knowledge about circRNA biogenesis and functions and summarized novel findings regarding their roles in TNBC development and progression. In addition, we discussed recent data about the importance of exosomes in the transport and export of circRNAs in TNBC. Deep knowledge of circRNA functions in metastasis and therapy responses could be an invaluable guide in the identification of novel therapeutic targets for advancing the treatment of TNBC.

Semicarbazides Carrying Indole Core: Synthesis, Cytotoxicity Evaluation against Human Breast Cancer Cell Lines, and Molecular Modeling Studies

In this article, we report the synthesis and cytotoxicity evaluation of novel indole-carrying semicarbazide derivatives (IS1-IS15). The target molecules were obtained by the reaction of aryl/alkyl isocyanates with 1H-indole-2-carbohydrazide that was in-house synthesized from 1H-indole-2-carboxylic acid. Following structural characterization by 1 H-NMR, 13 C-NMR, and HR-MS, IS1-IS15 were investigated for their cytotoxic activity against human breast cancer cell lines, MCF-7 and MDA-MB-231. According to the data obtained from the MTT assay, phenyl ring with a lipophilic group at its para-position and alkyl moiety were preferential substituents on the indole-semicarbazide scaffold for antiproliferative activity. The effect of IS12 (N-(4-chloro-3-(trifluoromethyl)phenyl)-2-(1H-indole-2-carbonyl)hydrazine-1-carboxamide), the compound that demonstrated remarkable antiproliferative activity on both cell lines, was also evaluated on the apoptotic pathway. Moreover, the calculation of critical descriptors constituting drug-likeness confirmed the position of the selected compounds in the anticancer drug development process. Finally, molecular docking studies suggested the inhibition of tubulin polymerization as the potential activity mechanism of this class of molecules.

Estrogen receptor status heterogeneity in breast cancer tumor: role in response to endocrine treatment

Tumor heterogeneity affects diagnosis, prognosis and response to therapy. Heterogeneity is found in both normal and neoplastic human mammary gland. Indeed, luminal ER-negative cells can give rise to various phenotypes, including ER-negative and ER-positive mammary tumors. As a result, the tumor phenotype does not necessarily reflects the cell of origin of cancer. With regard to the ER status, heterogeneity can challenge endocrine therapies, where the elimination of responsive clones could lead to reduced treatment efficacy and tumor relapse through the expansion of the resistant clones. The aim of this study was to investigate breast tumor heterogeneity and its role in endocrine resistance onset. For this purpose, we used ER⁺ (T47D, CAMA1) and triple-negative breast cancer cell lines (TNBC; MDA-MB-231, HCC70), co-cultures using 2D and 3D models. Our results showed that ER status is modulated when ER⁺ cells are cultured in the presence of TNBC cells, leading to a different response to endocrine therapy, demonstrating that the response to treatment can be affected by the influence that different breast cancer cell types exert on each other. In addition, ER⁺ positive cells doubling time was modified after exposure to TNBC cell co-culturing. Further experiments are required to fully elucidate the molecular mechanism of these observations.

Association of CCND1 (c.723G > A, rs9344) variant with elevated risk of breast carcinoma: a retrospective case-control study

BACKGROUND

The prevalence rate of breast carcinoma (BC) among multiple ethnic populations required more explanations to understand the pathogenesis mechanisms for the development of this type of cancer. The principal purpose of this work is to validate the correlation of the CCND1 (c.723G > A; rs9344) variant with an increased risk of breast carcinoma.

METHODS

This retrospective case-controlled study was designed appertaining to 200 women including 100 BC patients and 100 unrelated cancer-free controls. The amplification of genomic DNA was genotyped utilizing the PCR-RFLP technique.

RESULTS

The frequencies of the CCND1 (c.723G > A; rs9344) variant revealed a significant association with increased risk of breast carcinoma under different genetic models including allelic (OR = 2.84, P-value < 0.001), recessive (OR = 4.83, P-value < 0.001), and dominant (OR = 3.19, P-value < 0.001) models.

CONCLUSIONS

Our findings concluded that the genetic biomarker of the CCND1 (c.723G > A; rs9344) variant is correlated with an elevated risk of breast carcinoma among Egyptian women.

Effect of Exogenous pH on Cell Growth of Breast Cancer Cells

Breast cancer is the most common type of cancer in women and the most life-threatening cancer in females worldwide. One key feature of cancer cells, including breast cancer cells, is a reversed pH gradient which causes the extracellular pH of cancer cells to be more acidic than that of normal cells. Growing literature suggests that alkaline therapy could reverse the pH gradient back to normal and treat the cancer; however, evidence remains inconclusive. In this study, we investigated how different exogenous pH levels affected the growth, survival, intracellular reactive oxygen species (ROS) levels and cell cycle of triple-negative breast cancer cells from MDA-MB-231 cancer cell lines. Our results demonstrated that extreme acidic conditions (pH 6.0) and moderate to extreme basic conditions (pH 8.4 and pH 9.2) retarded cellular growth, induced cell death via necrosis and apoptosis, increased ROS levels, and shifted the cell cycle away from the G0/G1 phase. However, slightly acidic conditions (pH 6.7) increased cellular growth, decreased ROS levels, did not cause significant cell death and shifted the cell cycle from the G0/G1 phase to the G2/M phase, thereby explaining why cancer cells favored acidic conditions over neutral ones. Interestingly, our results also showed that cellular pH history did not significantly affect the subsequent growth of cells when the pH of the medium was changed. Based on these results, we suggest that controlling or maintaining an unfavorable pH (such as a slightly alkaline pH) for cancer cells in vivo could retard the growth of cancer cells or potentially treat the cancer.

Association of GSTP1 p.Ile105Val (rs1695, c.313A > G) Variant with the Risk of Breast Carcinoma among Egyptian Women

Several reports examined the association of the GSTP1 p.Ile105Val (rs1695, c.313A > G) variant with the elevated risk of multiple cancerous diseases involving breast carcinoma, but with inconclusive findings. The primary purpose of this study is to test the association of this essential variant with the risk of breast carcinoma among Egyptian females. This case-control study was conducted based on 200 participants involving 100 women diagnosed with breast carcinoma and 100 unrelated cancer-free controls from the same district. The genomic DNA for all participants was genotyped utilizing T-ARMS-PCR procedure. The frequencies of the GSTP1 p.Ile105Val (rs1695, c.313A > G) variant indicated a statistically significant with the elevated risk of breast carcinoma under various genetic models, including allelic (OR = 2.48, P-value < 0.001) and dominant (OR = 2.36, P-value = 0.003) models. In conclusion, the GSTP1 p.Ile105Val (rs1695, c.313A > G) variant was considered as an independent risk factor for breast carcinoma among Egyptian women.

Stratification of Estrogen Receptor-Negative Breast Cancer Patients by Integrating the Somatic Mutations and Transcriptomic Data

Patients with estrogen receptor-negative breast cancer generally have a worse prognosis than estrogen receptor-positive patients. Nevertheless, a significant proportion of the estrogen receptor-negative cases have favorable outcomes. Identifying patients with a good prognosis, however, remains difficult, as recent studies are quite limited. The identification of molecular biomarkers is needed to better stratify patients. The significantly mutated genes may be potentially used as biomarkers to identify the subtype and to predict outcomes. To identify the biomarkers of receptor-negative breast cancer among the significantly mutated genes, we developed a workflow to screen significantly mutated genes associated with the estrogen receptor in breast cancer by a gene coexpression module. The similarity matrix was calculated with distance correlation to obtain gene modules through a weighted gene coexpression network analysis. The modules highly associated with the estrogen receptor, called important modules, were enriched for breast cancer-related pathways or disease. To screen significantly mutated genes, a new gene list was obtained through the overlap of the important module genes and the significantly mutated genes. The genes on this list can be used as biomarkers to predict survival of estrogen receptor-negative breast cancer patients. Furthermore, we selected six hub significantly mutated genes in the gene list which were also able to separate these patients. Our method provides a new and alternative method for integrating somatic gene mutations and expression data for patient stratification of estrogen receptor-negative breast cancers.

Triple Negative Breast Cancer: A Review of Present and Future Diagnostic Modalities

Triple-negative breast cancer (TNBC) is an aggressive breast type of cancer with no expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2). It is a highly metastasized, heterogeneous disease that accounts for 10-15% of total breast cancer cases with a poor prognosis and high relapse rate within five years after treatment compared to non-TNBC cases. The diagnostic and subtyping of TNBC tumors are essential to determine the treatment alternatives and establish personalized, targeted medications for every TNBC individual. Currently, TNBC is diagnosed via a two-step procedure of imaging and immunohistochemistry (IHC), which are operator-dependent and potentially time-consuming. Therefore, there is a crucial need for the development of rapid and advanced technologies to enhance the diagnostic efficiency of TNBC. This review discusses the overview of breast cancer with emphasis on TNBC subtypes and the current diagnostic approaches of TNBC along with its challenges. Most importantly, we have presented several promising strategies that can be utilized as future TNBC diagnostic modalities and simultaneously enhance the efficacy of TNBC diagnostic.

The diagnostic power of circulating micro ribonucleic acid 34a in combination with cancer antigen 15-3 as a potential biomarker of breast cancer

Objectives:

To investigate the circulating levels of microRNA-34a (miRNA-34a) as a novel non-invasive biomarker of breast cancer (BC).

Methods:

The case-control study was conducted at the Department of Chemistry and Biochemistry, College of Medicine, Al-Nahrain University, Baghdad, Iraq, from December 2018 to April 2019. Real-time quantitative polymerase chain reaction has been employed to analyze miRNA-34a expression in the samples of serum from 90 participants (30 patients with BC, 30 patients with benign breast tumors, and 30 control subjects) after RNA extraction and reverse transcription. Cancer antigen 15-3 (CA15-3) and carcinoembryonic antigen (CEA) were measured by ELISA. Additionally, we analyzed the receiver operating characteristic curves of various markers, including miRNA -34a, CA15-3, and CEA, to assess the diagnostic power of each marker.

Results:

The expression of miRNA-34a has been significantly lower in the group of breast cancer compared with that in the group of control, and miRNA-34a expression has been significantly reduced in the group of benign breast tumor compared as that in the group of control. Receiver operating characteristics analysis showed a very good discriminative power of combined miRNA-34a and CA15-3 (specificity=77.7%; sensitivity=83.3% and areas under the curve =0.842) for BC patients.

Conclusion:

MicroRNA-34a expression is significantly decreased in the patients’ serum with the cancer of breast, and miRNA-34a can be employed as a potential non-invasive molecular marker for the early diagnosis of BC.