Her2-Positive Cancers and Antibody-Based Treatment: State of the Art and Future Developments

HER2 positive breast cancer represent about 20% of all breast cancer subtypes and it was considered the subtype with the worst prognosis until the discovery of therapies directed against the HER2 protein. The determination of the status of the HER2 must be very precise and well managed to identify this subtype, and there are very specific and updated guides that allow its characterization to be adjusted. Treatment in local disease has been considerably improved with less aggressive and highly effective approaches and very high cure rates. In metastatic disease, average median survival rates of 5 years have been achieved. New highly active molecules have also been discovered that allow disease control in very complicated situations. This article reviews all these options that can be used for the management of this disease.

ELISA and Fourier-transform infrared spectroscopy

ELISA and FTIR assay techniques were used to identify HER2 gene expression in the blood serum of female dogs and to characterise the biochemical composition. ELISA tests assess the stage of primary tumour development and evolution, while FTIR allows for a complete characterisation of biomolecules associated with the tumoral process. Blood serum samples from 30 female dogs were analysed. Concentrations of the HER2/neu protein were detected using ELISA kits specific for canine and human detection. Infrared spectroscopy (IR) was conducted in absorbance mode at a frequency range of 400–4000 cm-1 and a resolution of 4 cm-1 over 50 scans. The ELISA cut-off for HER2 protein concentration in blood serum was determined using the receiver operating characteristic (ROC) curve and by estimating the area under the curve (AUC) at a 95% confidence interval (CI=95%). The ROC curves in the canine and human ELISA tests were 0.75 and 0.45, respectively. The representative IR spectra for HER2 gene expression corresponded to lipids (1161 cm-1, 1452 cm-1, 2851 cm-1). This study contributes to the knowledge of HER2 through the identification of biochemical features associated with the changes in the HER2/neu+ and HER2/neu- states.

Detection of Genetic Polymorphism of HER2 Gene in HER2 Positive Breast Cancer Women in Iraq

The human epidermal growth factor receptor-2 (HER2) gene plays a critical role in breast cancer development and progression. HER2 overexpression characterizes a biologically and clinically aggressive breast cancer subtype. In this study, 60 samples from Iraqi women with breast cancer were collected and investigated for HER2 protein in the tissue by immunohistochemistry. Also, 20 samples from healthy Iraqi women were used as a control. The results showed that 18 (30 %) patients expressed the HER2 protein. A molecular study for single nucleotide polymorphism (SNP) was conducted on samples metastasizing to lymph nodes. DNA was extracted and polymerase chain reaction (PCR) was performed to amplify exon 17 and intron 17 of HER2 gene. Sequencing of PCR product was achieved and two SNPs of HER2 gene, one in exon 17 (Ile655Val) and another close to it in intron 17 (rs903506) were studied. In exon 17, SNP Ile655Val was found in 41% of patients, while in intron 17, the non-coding SNP rs903506 was found in 27% of patients. However, no polymorphism was found in the control group. The results may suggest that HER2 gene can be used as a molecular marker for breast cancer.

Melatonin potentiates the cytotoxic effect of Neratinib in HER2+ breast cancer through promoting endocytosis and lysosomal degradation of HER2

Complete blockade of the HER2 protein itself and HER signaling network is critical to achieving effective HER2-targeted therapies. Despite the success of HER2-targeted therapies, the diseases will relapse in a significant fraction of patients with HER2+ breast cancers. How to improve the therapeutic efficacy of existing HER2-targeted agents remains an unmet clinical need. Here, we uncover a role of Melatonin in diminishing HER2-mediated signaling by destruction of HER2 protein. Mechanistically, Melatonin treatment attenuated the protective effect of the HSP90 chaperone complex on its client protein HER2, triggering ubiquitylation and subsequent endocytic lysosomal degradation of HER2. The inhibitory effect of Melatonin on HER2 signaling substantially enhanced the cytotoxic effects of the pan-HER inhibitor Neratinib in HER2+ breast cancer cells. Lastly, we demonstrate that dual inhibition of HER2 by combined use of Melatonin and Neratinib effectively blocked the growth of HER2+ breast tumor xenografts in vivo. Our findings shed light on the potential use of Melatonin in a novel dual HER2 blockade strategy for HER2+ breast cancer treatment.

CBP/p300 Bromodomain Inhibitor–I–CBP112 Declines Transcription of the Key ABC Transporters and Sensitizes Cancer Cells to Chemotherapy Drugs

The high expression of some ATP-binding cassette (ABC) transporters is linked to multidrug resistance in cancer cells. We aimed to determine if I-CBP112, which is a CBP/p300 bromodomain inhibitor, altered the vulnerability of the MDA-MB-231 cell line to chemotherapy drugs, which are used in neoadjuvant therapy in patients with triple negative breast cancer (TNBC). MDA-MB-231 cells represent TNBC, which is negative for the expression of estrogen and progesterone receptors and HER2 protein. An I-CBP112-induced decrease in the expression of all the studied ABCs in the breast, but also in the lung (A549), and hepatic (HepG2) cancer cell lines was associated with increased accumulation of doxorubicin, daunorubicin, and methotrexate inside the cells as well as with considerable cell sensitization to a wide range of chemotherapeutics. Gene promoters repressed by I-CBP112 in MDA-MB-231 cells, such as ABCC1 and ABCC10, were characterized by enhanced nucleosome acetylation and, simultaneously, by considerably lower trimethylation in the transcription-promoting form of H3K4me3. The CBP/p300 bromodomain inhibitor induced the recruitment of LSD1 to the gene promoters. The inhibition of this demethylase in the presence of I-CBP112 prevented the repression of ABCC1 and ABCC10 and, to a considerable extent, cancer cells’ sensitization to drugs. In conclusion, the CBP/p300 bromodomain inhibitor I-CBP112 can be considered as a potent anti-multidrug-resistance agent, capable of repressing key ABC transporters responsible for drug efflux in various cancer types.

Utilization of Intravenous (IV) Curcumin, Genistein, and Trastuzumab to Reduce HER2 receptors in Breast Cancer Patients

In recent decades, due to the increased growth, spread, and onset of cancer, interest has arisen in studying the methods that could be used to combat it. Breast cancer is the most prevalent form of cancer in the world. Due to the growing pervasiveness of this issue, a larger body of research is forming in the area of breast cancer with the intent to contain the spread of the potentially ravaging disease or diagnose it earlier. This research is intended to propose an alternative, possibly more efficient method to inhibit the chances of metastasis and continued prevalence of breast cancer in a patient. The related work discusses similar research being done and builds on it to incorporate the novel method being proposed while explaining the components of the proposed treatment in question. The proposed method aims to deplete HER2 protein receptors in breast cancer patients through the intravenous (IV) administration of the tyrosine kinase inhibitors (TKIs) curcumin and genistein, as well as trastuzumab, which is more commonly known under the brand name Herceptin. Depleting HER2 protein receptors can potentially cause the severity of HER2-positive breast cancer to decrease substantially, as well as reduce the probability of metastasis and recurrence, the rate of which is considerably higher in HER2-positive cases when compared to that of HER2-negative cases. The future work deals with alternate methods that could be explored with a similar intent as this research study and describes the potential implications of the study.