Promising molecular targeted therapies in breast cancer

Tumor Organoids: The Era of Personalized Medicine

The strategies of future medicine are aimed to modernize and integrate quality approaches including early molecular-genetic profiling, identification of new therapeutic targets and adapting design for clinical trials, personalized drug screening (PDS) to help predict and individualize patient treatment regimens. In the past decade, organoid models have emerged as an innovative in vitro platform with the potential to realize the concept of patient-centered medicine. Organoids are spatially restricted three-dimensional clusters of cells ex vivo that self-organize into complex functional structures through genetically programmed determination, which is crucial for reconstructing the architecture of the primary tissue and organs. Currently, there are several strategies to create three-dimensional (3D) tumor systems using (i) surgically resected patient tissue (PDTOs, patient-derived tumor organoids) or (ii) single tumor cells circulating in the patient's blood. Successful application of 3D tumor models obtained by co-culturing autologous tumor organoids (PDTOs) and peripheral blood lymphocytes have been demonstrated in a number of studies. Such models simulate a 3D tumor architecture in vivo and contain all cell types characteristic of this tissue, including immune system cells and stem cells. Components of the tumor microenvironment, such as fibroblasts and immune system cells, affect tumor growth and its drug resistance. In this review, we analyzed the evolution of tumor models from two-dimensional (2D) cell cultures and laboratory animals to 3D tissue-specific tumor organoids, their significance in identifying mechanisms of antitumor response and drug resistance, and use of these models in drug screening and development of precision methods in cancer treatment.

Extracellular Guanosine and Guanine Nucleotides Decrease Viability of Human Breast Cancer SKBR-3 Cells

Though the physiological effects of adenosine and adenine nucleotides on purinergic receptors in cancer cells have been well studied, the influence of extracellular guanosine and guanine nucleotides on breast cancer cells remains unclear. Here, we show that extracellular guanosine and guanine nucleotides decrease the viability and proliferation of human breast cancer SKBR-3 cells. Treatment with guanosine or guanine nucleotides increased mitochondrial production of reactive oxygen species (ROS), and modified the cell cycle. Guanosine-induced cell death was suppressed by treatment with adenosine or the equilibrium nucleoside transporter (ENT) 1/2 inhibitor dipyridamole, but was not affected by adenosine receptor agonists or antagonists. These results suggest that guanosine inhibits adenosine uptake through ENT1/2, but does not antagonize adenosine receptors. In contrast, guanosine triphosphate (GTP)-induced cell death was suppressed not only by adenosine and dipyridamole, but also by the A1 receptor agonist 2-chloro-N6-cyclopentyladenosine (CCPA), suggesting that GTP-induced cell death is mediated in part by an antagonistic effect on adenosine A1 receptor. Thus, both guanosine and GTP induce apoptosis of breast cancer cells, but via at least partially different mechanisms.

A review of nanomaterials from synthetic and natural molecules for prospective breast cancer nanotherapy

Breast cancer being one of the most frequent cancers in women accounts for almost a quarter of all cancer cases. Early and late-stage breast cancer outcomes have improved dramatically, with considerable gains in overall survival rate and disease-free state. However, the current therapy of breast cancer suffers from drug resistance leading to relapse and recurrence of the disease. Also, the currently used synthetic and natural agents have bioavailability issues which limit their use. Recently, nanocarriers-assisted delivery of synthetic and natural anticancer drugs has been introduced to the breast cancer therapy which alienates the limitations associated with the current therapy to a great extent. Significant progress has lately been made in the realm of nanotechnology, which proved to be vital in the fight against drug resistance. Nanotechnology has been successfully applied in the effective and improved therapy of different forms of breast cancer including invasive, non-invasive as well as triple negative breast cancer (TNBC), etc. This review presents a comprehensive overview of various nanoformulations prepared for the improved delivery of synthetic and natural anticancer drugs alone or in combination showing better efficacy and pharmacokinetics. In addition to this, various ongoing and completed clinical studies and patents granted on nanotechnology-based breast cancer drug delivery are also reviewed.

Identification and validation of a prognostic risk model based on caveolin family genes for breast cancer

Background: Breast cancer (BC) is the most vicious killer of women’s health and is accompanied by increased incidence and mortality rates worldwide. Many studies have demonstrated that caveolins (CAVs) were abnormally expressed in a variety of tumors and implicated in tumorigenesis and cancer progression. However, the role of CAVs in BC remains somewhat contentious.

Methods: We comprehensively explored the expression and prognostic value of CAVs (CAV1-3) in BC utilizing public databases (ONCOMINE, TIMER, UALCAN, and TCGA databases). Then we constructed a prognostic model based on the expression profiles. Also, a prognostic nomogram was built to predict the overall survival (OS). We further investigated the relationship between this signature and immune cell infiltration and the mutational landscape in BC. The R package “pRRophetic” was used to predict chemotherapeutic response in BC patients. Finally, we employed loss-of-function approaches to validate the role of CAVs in BC.

Results: We found that CAVs were significantly downregulated in various cancer types, especially in BC. Low CAV expression was closely related to the malignant clinicopathological characteristics and worse OS and relapse-free survival (RFS) in BC. Then we constructed a prognostic model based on the expression profiles of CAVs, which divided BC patients into two risk groups. The Kaplan–Meier analysis showed that patients in the high-risk group tend to have a poorer prognosis than those in the low-risk group. Multivariate analysis indicated that the risk score and stage were both independent prognostic factors for BC patients, suggesting a complementary value. The clinical profiles and risk module were used to construct a nomogram that could accurately predict the OS in BC. In addition, we found that patients in the low-risk group tend to have a relatively high immune status and a lower mutation event frequency compared to the high-risk group. Furthermore, this signature could predict the response to chemotherapy and immunotherapy. Finally, CAV depletion promoted the colony formation, migration, and invasion of BC cells.

Conclusion: CAVs may serve as novel biomarkers and independent prognostic factors for BC patients. Also, the constructed signature based on CAVs may predict immunotherapeutic responses and provide a novel nomogram for precise outcome prediction of BC.

YES1 as a Therapeutic Target for HER2-Positive Breast Cancer after Trastuzumab and Trastuzumab-Emtansine (T-DM1) Resistance Development

Trastuzumab-emtansine (T-DM1) is a therapeutic agent molecularly targeting human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC), and it is especially effective for MBC with resistance to trastuzumab. Although several reports have described T-DM1 resistance, few have examined the mechanism underlying T-DM1 resistance after the development of acquired resistance to trastuzumab. We previously reported that YES1, a member of the Src family, plays an important role in acquired resistance to trastuzumab in HER2-amplified breast cancer cells. We newly established a trastuzumab/T-DM1-dual-resistant cell line and analyzed the resistance mechanisms in this cell line. At first, the T-DM1 effectively inhibited the YES1-amplified trastuzumab-resistant cell line, but resistance to T-DM1 gradually developed. YES1 amplification was further enhanced after acquired resistance to T-DM1 became apparent, and the knockdown of the YES1 or the administration of the Src inhibitor dasatinib restored sensitivity to T-DM1. Our results indicate that YES1 is also strongly associated with T-DM1 resistance after the development of acquired resistance to trastuzumab, and the continuous inhibition of YES1 is important for overcoming resistance to T-DM1.

Immunotherapy for Breast Cancer Treatment

Breast cancer, as a heterogeneous disease, includes a wide range of pathological and clinical behaviors. Current treatment protocols, including radiotherapy, chemotherapy, and hormone replacement therapy, are mainly associated with poor response and high rate of recurrence. Therefore, more efforts are needed to develop alternative therapies for this type of cancer. Immunotherapy, as a novel strategy in cancer treatment, has a potential in treating breast cancer patients. Although breast cancer has long been considered problematic to treat with immunotherapy, as it is immunologically "cold," numerous newer preclinical and clinical reports now recommend that immunotherapy has the capability to treat breast cancer patients. In this review, we highlight the different immunotherapy strategies in breast cancer treatment.

Exosomal-mediated transfer of OIP5-AS1 enhanced cell chemoresistance to trastuzumab in breast cancer via up-regulating HMGB3 by sponging miR-381-3p

Background

Long noncoding RNA OPA-interacting protein 5 antisense transcript 1 (OIP5-AS1) was confirmed to involve in the malignancy of breast cancer. However, whether exosomal OIP5-AS1 is implicated in trastuzumab resistance remains unclear.

Methods

The IC₅₀ value of cells to trastuzumab, cell proliferation, migration, and apoptosis was analyzed by cell counting kit-8 assay, colony formation assay, transwell assay, or flow cytometry, respectively. The expression of OIP5-AS1 and microRNA (miR)-381-3p was detected using quantitative real-time polymerase chain reaction. Exosomes were isolated by ultracentrifugation and qualified by nanoparticle tracking analysis software. Western blot was used to detect the protein levels of tumor susceptibility gene 101 (TSG101), CD81, CD63, or high-mobility group protein B3 (HMGB3). The interaction between miR-381-3p and OIP5-AS1 or HMGB3 was confirmed by dual-luciferase reporter assay and pull-down assay. In vivo experiments were conducted using murine xenograft models.

Results

OIP5-AS1 was elevated in trastuzumab-resistant breast cancer cells, and OIP5-AS1 knockdown rescued trastuzumab sensitivity. Extracellular OIP5-AS1 was packaged into exosomes, which were secreted by trastuzumab-resistant cells, and could be absorbed by trastuzumab-sensitive cells in breast cancer. Importantly, intercellular transfer of OIP5-AS1 via exosomes enhanced trastuzumab resistance in vitro. OIP5-AS1 was a sponge of miR-381-3p; besides, miR-381-3p targeted HMGB3. Murine xenograft analysis showed exosomal OIP5-AS1 induced trastuzumab resistance in vivo. Exosomal OIP5-AS1 was dysregulated in the serum of breast cancer patients and might be a promising diagnostic biomarker in trastuzumab resistance.

Conclusion

Intercellular transfer of OIP5-AS1 by exosomes enhanced trastuzumab resistance in breast cancer via miR-381-3p/HMGB3 axis, indicating a potential therapeutic strategy to boost the effectiveness of trastuzumab in resistant breast cancer patients.

Clinical study of modulated electro-hyperthermia for advanced metastatic breast cancer

Modulated electro-hyperthermia (mEHT) is a new treatment modality developed to overcome the problems associated with traditional hyperthermia; mEHT uses a precise impedance-matched system and modulated radiofrequency current flow to malignant tumors. It selects the malignant cells based on their biophysical differences, due to their high metabolic rate, individual (autonomic) behavior and membrane status. The aim of the present study was to report the outcomes of mEHT in the treatment of advanced breast cancer. mEHT was examined in 10 patients with advanced metastatic breast cancer and recurrent disease, who were considered incurable by standard therapy protocols. Of the 10 patients, partial response was achieved in 3, disease stability in 3, and progressive disease in 4; however, their quality of life was improved based on their subjective reports. No adverse effects were observed in any of the 10 patients. The present study demonstrated the feasibility of mEHT as a possible therapy for advanced breast cancer cases when standard therapies fail. Moreover, mEHT had no side effects and may be combined with various treatments for long-term therapy.

Immunotherapy for Breast Cancer Treatment

Breast cancer, as a heterogeneous disease, includes a wide range of pathological and clinical behaviors. Current treatment protocols, including radiotherapy, chemotherapy, and hormone replacement therapy, are mainly associated with poor response and high rate of recurrence. Therefore, more efforts are needed to develop alternative therapies for this type of cancer. Immunotherapy, as a novel strategy in cancer treatment, has a potential in treating breast cancer patients. Although breast cancer has long been considered problematic to treat with immunotherapy, as it is immunologically "cold," numerous newer preclinical and clinical reports now recommend that immunotherapy has the capability to treat breast cancer patients. In this review, we highlight the different immunotherapy strategies in breast cancer treatment.

Breast cancer therapy affects the expression of antineonatal Nav1.5 antibodies in the serum of patients with breast cancer

Neonatal Nav1.5 (nNav1.5) is the alternative splice variant of Nav1.5 and it has been widely associated with the progression of breast cancer. The immunological context of nNav1.5 with respect to breast cancer metastases remains unexplored. The presence of antibodies against nNav1.5 may highlight the immunogenicity of nNav1.5. Hence, the aim of the present study was to detect the presence of antineonatal Nav1.5 antibodies (antinNav1.5-Ab) in the serum of patients with breast cancer and to elucidate the effects of breast cancer therapy on its expression. A total of 32 healthy female volunteers and 64 patients with breast cancer were randomly recruited into the present study as the control and breast cancer group, respectively. Patients with breast cancer were divided equally based on their pre- and ongoing-treatment status. Serum samples were tested with in-house indirect enzyme-linked immunosorbent assay (ELISA) to detect antinNav1.5-Ab, CD25 (T regulatory cell marker) using an ELISA kit and Luminex assay to detect the expression of metastasis-associated cytokines, such as vascular endothelial growth factor (VEGF), interleukin (IL)-6, IL-10, IL-8, chemokine (C-C motif) ligand 2 and tumor necrosis factor-alpha (TNF-α) The mean difference in the expression of antinNav1.5-Ab among the three groups (control, pretreatment and ongoing-treatment) was significant (P=0.0005) and the pretreatment breast cancer group exhibited the highest expression. The concentration of CD25 was highest in the pretreatment breast cancer group compared with the control and ongoing-treatment groups. There was a significant positive correlation between antinNav1.5-Ab and IL-6 in the pretreatment group (r=0.7260; P=0.0210) and a significant negative correlation between antinNav1.5-Ab and VEGF in the ongoing-treatment group (r=-0.842; P-value=0.0040). The high expression of antinNav1.5-Ab in the pretreatment group was in accordance with the uninterrupted presence of metastasis and highlighted the immunogenicity of nNav1.5 whereas the low expression of antinNav1.5-Ab in the ongoing-treatment group reflected the efficacy of breast cancer therapy in eliminating metastases. The augmented manifestation of T regulatory cells in the pretreatment group highlighted the functional role of nNav1.5 in promoting metastasis. The parallel expression of antinNav1.5-Ab with the imbalanced expression of cytokines promoting metastasis (IL-8, IL-6 and TNF-α) and cytokines that prevent metastasis (IL-10) indicated the role of nNav1.5 in breast cancer growth. The expression of antinNav1.5-Ab in accordance to the metastatic microenvironment indicates the immunogenicity of the protein and highlights the influence of breast cancer therapy on its expression level.

Role of miRNAs in regulating responses to radiotherapy in human breast cancer

Breast cancer is the most common type of cancer that affects females globally. Radiotherapy is a standard treatment option for breast cancer, where one of its most significant limitations is radioresistance development. MicroRNAs (miRNAs) are small, non-protein-coding RNAs that have been widely studied for their roles as disease biomarkers. To date, several in vitro, in vivo, and clinical studies have reported the roles of miRNAs in regulating radiosensitivity and radioresistance in breast cancer cells. This article reviews the roles of miRNAs in regulating treatment response toward radiotherapy and the associating cellular pathways. We identified 36 miRNAs that play a role in mediating radio-responses; 22 were radiosensitizing, 12 were radioresistance-promoting, and two miRNAs were reported to promote both effects. A brief overview of breast cancer therapy options, mechanism of action of radiation, and molecular mechanism of radioresistance was provided in this article. A summary of the latest clinical researches involving miRNAs in breast cancer radiotherapy was also included.

Experimental Models as Refined Translational Tools for Breast Cancer Research

Breast cancer is one of the most common cancers worldwide, which makes it a very impactful malignancy in the society. Breast cancers can be classified through different systems based on the main tumor features and gene, protein, and cell receptors expression, which will determine the most advisable therapeutic course and expected outcomes. Multiple therapeutic options have already been proposed and implemented for breast cancer treatment. Nonetheless, their use and efficacy still greatly depend on the tumor classification, and treatments are commonly associated with invasiveness, pain, discomfort, severe side effects, and poor specificity. This has demanded an investment in the research of the mechanisms behind the disease progression, evolution, and associated risk factors, and on novel diagnostic and therapeutic techniques. However, advances in the understanding and assessment of breast cancer are dependent on the ability to mimic the properties and microenvironment of tumors in vivo, which can be achieved through experimentation on animal models. This review covers an overview of the main animal models used in breast cancer research, namely in vitro models, in vivo models, in silico models, and other models. For each model, the main characteristics, advantages, and challenges associated to their use are highlighted.

Thiazole-containing compounds as therapeutic targets for cancer therapy

In the last few decades, considerable progress has been made in anticancer agents development, and several new anticancer agents of natural and synthetic origin have been produced. Among heterocyclic compounds, thiazole, a 5-membered unique heterocyclic motif containing sulphur and nitrogen atoms, serves as an essential core scaffold in several medicinally important compounds. Thiazole nucleus is a fundamental part of some clinically applied anticancer drugs, such as dasatinib, dabrafenib, ixabepilone, patellamide A, and epothilone. Recently, thiazole-containing compounds have been successfully developed as possible inhibitors of several biological targets, including enzyme-linked receptor(s) located on the cell membrane, (i.e., polymerase inhibitors) and the cell cycle (i.e., microtubular inhibitors). Moreover, these compounds have been proven to exhibit high effectiveness, potent anticancer activity, and less toxicity. This review presents current research on thiazoles and elucidates their biological importance in anticancer drug discovery. The findings may aid researchers in the rational design of more potent and bio-target specific anticancer drug molecules.

Breast Cancer Targeted Treatment Strategies: Promising Nanocarrier Approaches

Breast cancer is the second most common cancer that causes death among women worldwide. Incidence of breast cancer is increasing worldwide, and the age at which breast cancer develops has shifted from 50- 70 years to 30-40 years. Chemotherapy is the most commonly used effective treatment strategy to combat breast cancer. However, one of the major drawbacks is low selective site-specificity and the consequent toxic insult to normal healthy cells. The nanocarrier system is consistently utilised to minimise the various limitations involved in the conventional treatment of breast cancer. The nanocarrier based targeted drug delivery system provides better bioavailability, prolonged circulation with an effective accumulation of drugs at the tumour site either by active or passive drug targeting. Active targeting has been achieved by receptor/protein anchoring and externally guided magnetic nanocarriers, whereas passive targeting accomplished by employing the access to the tunnel via leaky tumour vasculature, utilising the tumour microenvironment, because the nanocarrier systems can reduce the toxicity to normal cells. As of now a few nanocarrier systems have been approved by FDA, and various nanoformulations are in the pipeline at the preclinical and clinical development for targeting breast cancer; among them, polymeric micelles, microemulsions, magnetic microemulsions, liposomes, dendrimers, carbon nanotubes, and magnetic Nanoparticles (NPs) are the most common. The current review highlights the active and passive targeting potential of nanocarriers in breast cancer and discusses their role in targeting breast cancer without affecting normal healthy cells.

A Brief Literature and Review of Patents on Thiazole Related Derivatives

Background:

Thiazole is widely investigated bioactive scaffold and dynamic tool in medicinal chemistry research. Significance of thiazole compounds are well documented as thiazole is an obligatory structure of number of currently available therapeutics. In spite of that, thiazole derivatives are endowed with myriad biological activities, such as antiviral, anticancer, antibacterial, antifungal, antimalarial, antiparkinsonian, anti-inflammatory activities and many more.

Methods:

In recent past, different approaches have been introduced for synthesis of thiazole and related compounds. Intrinsic molecular interaction between newly synthesized thiazole compounds and plethora of drug targets/enzymes has rendered discovery of new drug molecules with advances in modes of action. A renewed interest in therapeutic use of thiazole derivatives has been seen among the prospective researchers as exemplified by influx of huge scientific articles and patents. Some important patents of anti-infective and anticancer interest have been addressed appropriately and are presented in tables.

Results:

This review paper is a contemporary approach on therapeutic/applications of thiazole derivatives by summarizing important patents filed from 2000-2017. The main focus of these patents is on anti-infective and anticancer potential of thiazole based compounds.

Conclusion:

These approaches may provide valuable information for the further design of more active biological agents through various modifications and derivatizations.

Transcriptional activation of EGFR by HOXB5 and its role in breast cancer cell invasion

HOX genes are transcription factors that play important roles in body patterning and many cellular processes during embryonic, fetal, and adult development. Given their important function in normal tissues, it is reasonable to assume that abnormal expression of HOX genes in adults could lead to serious diseases such as cancer. Our previous study reported HOXB5 to be significantly up-regulated in breast cancer, and its expression was found to be associated with tumor cell proliferation and invasion. Furthermore, the epidermal growth factor receptor (EGFR), a cellular tyrosine kinase that plays an important role in breast cancer progression, was found significantly up-regulated by HOXB5 in ER-positive breast cancer cells. In the present study, we demonstrated that HOXB5 regulates EGFR expression at the transcriptional level by directly binding to its promoter region and promotes phosphorylation of EGFR as well as its downstream effectors. Patients with ER-positive breast cancer, having high co-expression of HOXB5 and EGFR, had poor prognosis than those with low expression. Knockdown studies validated a key role played by EGFR in the HOXB5-induced invasion of breast cancer cells. These results suggest that targeting EGFR could be an effective strategy to treat breast cancer in patients with high HOXB5 expression.

The interplay between AR, EGF receptor and MMP-9 signaling pathways in invasive prostate cancer

Background

Metastatic Prostate cancer (PCa) cells have gained survival and invasive advantages. Epidermal growth factor (EGF) receptor is a receptor tyrosine kinase, which may mediate signalling to promote progression and invasion of various cancers. In this study, we uncovered the molecular mechanisms underlying the interconnection among the androgen receptor (AR), matrix metalloproteinase-9 (MMP9) and EGFR in promoting PCa progression.

Methods

Immunohistochemical analysis of the tissue microarrays consisting of primary and metastatic PCa tissues was performed. The clinical importance of EGFR and its association with survivals were analyzed using three cohorts from MSKCC Prostate Oncogenome Project dataset (For primary tumors, n = 181; for metastatic tumors n = 37) and The Cancer Genome Atlas Prostate Adenocarcinoma Provisional dataset (n = 495). Targeted overexpression or inhibition of the proteins of interests was introduced into PCa cell lines. Treatment of PCa cell lines with the compounds was conducted. Immunoblot analysis was performed.

Results

We showed that AR, MMP-9 and EGFR are interconnect factors, which may cooperatively promote PCa progression. Altered EGFR expression was associated with poor disease-free survival in PCa patients. Induced overexpression of AR led to an increase in the expression of EGFR, p-GSK-3β and decrease in p27 expression in PCa cell lines in the presence of androgen stimulation. Overexpression of MMP9 significantly induced EGFR expression in PCa cells. Inhibition of PIP5K1α, a lipid kinase that acts upstream of PI3K/AKT greatly reduced expressions of AR, MMP-9 and EGFR.

Conclusions

Our findings also suggest that PCa cells may utilize AR, EGFR and MMP-9 pathways in androgen-dependent as well as in castration-resistant conditions. Our data suggest a new therapeutic potential to block cancer metastasis by targeting AR, EGFR and MMP-9 pathways in subsets of PCa patients.

Copper complex derived from S-benzyldithiocarbazate and 3-acetylcoumarin induced apoptosis in breast cancer cell

Copper complexes have been widely studied for the anti-tumour application as cancer cells are reported to take up greater amounts of copper than normal cells. Preliminary study revealed that the newly synthesised copper complex [Cu(SBCM)₂] displayed marked anti-proliferative towards triple-negative MDA-MB-231 breast cancer cells. Therefore, Cu(SBCM)₂ has great potential to be developed as an agent for the management of breast cancer. The present study was carried out to investigate the mode of cell death induced by Cu(SBCM)₂ towards MDA-MB-231 breast cancer cells. The inhibitory and morphological changes of MDA-MB-231 cells treated with Cu(SBCM)₂ was determined by using MTT assay and inverted light microscope, respectively. The safety profile of Cu(SBCM)₂ was also evaluated towards human dermal fibroblast (HDF) normal cells. Confirmation of apoptosis and cell cycle arrest were determined by flow cytometry analysis. The expression of p53, Bax, Bcl-2 and MMP2 protein were detected with western blot analysis. Cu(SBCM)₂ significantly inhibited the growth of MDA-MB-231 cells in a dose-dependent manner with GI₅₀ 18.7 ± 3.06 µM. Indeed, Cu(SBCM)₂ was less toxic towards HDF normal cells with GI₅₀ 31.8 ± 4.0 µM. Morphological study revealed that Cu(SBCM)₂-treated MDA-MB-231 cells experienced cellular shrinkage, membrane blebbing, chromatin condensation and formation of apoptotic bodies, suggesting that Cu(SBCM)₂ induced apoptosis in the cells, which was confirmed by Annexin-V/PI flow cytometry analysis. It was also found that Cu(SBCM)₂ induced G₂/M phase cell cycle arrest towards MDA-MB-231 cells. The induction of apoptosis and cell cycle arrest in the present study is possibly due to the down-regulation of the mutant p53 and MMP2 protein. In conclusion, Cu(SBCM)₂ can be developed as a targeted therapy for the treatment of triple-negative breast cancer.

'Lnc'-ing Wnt in female reproductive cancers: therapeutic potential of long non-coding RNAs in Wnt signalling

Recent discoveries in the non-coding genome have challenged the original central dogma of molecular biology, as non-coding RNAs and related processes have been found to be important in regulating gene expression. MicroRNAs and long non-coding RNAs (lncRNAs) are among those that have gained attention recently in human diseases, including cancer, with the involvement of many more non-coding RNAs (ncRNAs) waiting to be discovered. ncRNAs are a group of ribonucleic acids transcribed from regions of the human genome, which do not become translated into proteins, despite having essential roles in cellular physiology. Deregulation of ncRNA expression and function has been observed in cancer pathogenesis. Recently, the roles of a group of ncRNA known as lncRNA have gained attention in cancer, with increasing reports of their oncogenic involvement. Female reproductive cancers remain a leading cause of death in the female population, accounting for almost a third of all female cancer deaths in 2016. The Wnt signalling pathway is one of the most important oncogenic signalling pathways which is hyperactivated in cancers, including female reproductive cancers. The extension of ncRNA research into their mechanistic roles in human cancers has also led to novel reported roles of ncRNAs in the Wnt pathway and Wnt-mediated oncogenesis. This review aims to provide a critical summary of the respective roles and cellular functions of Wnt-associated lncRNAs in female reproductive cancers and explores the potential of circulating cell-free lncRNAs as diagnostic markers and lncRNAs as therapeutic targets.

LINKED ARTICLES

This article is part of a themed section on WNT Signalling: Mechanisms and Therapeutic Opportunities. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.24/issuetoc.

Novel Strategies on Personalized Medicine for Breast Cancer Treatment: An Update

Breast cancer is the most common cancer type among women worldwide. With breast cancer patients and survivors being reported to experience a repertoire of symptoms that are detrimental to their quality of life, the development of breast cancer treatment strategies that are effective with minimal side effects is therefore required. Personalized medicine, the treatment process that is tailored to the individual needs of each patient, is recently gaining increasing attention for its prospect in the development of effective cancer treatment regimens. Indeed, recent studies have identified a number of genes and molecules that may be used as biomarkers for predicting drug response and severity of common cancer-associated symptoms. These would provide useful clues not only for the determination of the optimal drug choice/dosage to be used in personalized treatment, but also for the identification of gene or molecular targets for the development of novel symptom management strategies, which ultimately would lead to the development of more personalized therapies for effective cancer treatment. In this article, recent studies that would provide potential new options for personalized therapies for breast cancer patients and survivors are reviewed. We suggest novel strategies, including the optimization of drug choice/dosage and the identification of genetic changes that are associated with cancer symptom occurrence and severity, which may help in enhancing the effectiveness and acceptability of the currently available cancer therapies.

Imaging Considerations and Interprofessional Opportunities in the Care of Breast Cancer Patients in the Neoadjuvant Setting

OBJECTIVE

To discuss standard-of-care and emerging imaging techniques employed for screening and detection, diagnosis and staging, monitoring response to therapy, and guiding cancer treatments.

DATA SOURCES

Published journal articles indexed in the National Library of Medicine database and relevant websites.

CONCLUSION

Imaging plays a fundamental role in the care of cancer patients and specifically, breast cancer patients in the neoadjuvant setting, providing an excellent opportunity for interprofessional collaboration between oncologists, researchers, radiologists, and oncology nurses. Quantitative imaging strategies to assess cellular, molecular, and vascular characteristics within the tumor is needed to better evaluate initial diagnosis and treatment response.

IMPLICATIONS FOR NURSING PRACTICE

Nurses caring for patients in all settings must continue to seek education on emerging imaging techniques. Oncology nurses provide education about the test, ensure the patient has appropriate pre-testing instructions, and manage patient expectations about timing of results availability.

Human Antibody Fusion Proteins/Antibody Drug Conjugates in Breast and Ovarian Cancer

Considerable research efforts have been dedicated to understanding ovarian and breast cancer mechanisms, but there has been little progress translating the research into effective clinical applications. Hence, personalized/precision medicine has emerged because of its potential to improve the accuracy of tumor targeting and minimize toxicity to normal tissue. Targeted therapy in both breast and ovarian cancer has focused on antibodies, antibody drug conjugates (ADCs), and very recently the introduction of human antibody fusion proteins. Small molecule inhibitors and monoclonal antibodies (mAbs) are used in conjunction with chemotherapeutic drugs as a form of treatment but problems arise from a board expression of the target antigen in healthy tissues. Also, insufficient tumor penetration due to tight binding affinity and macromolecular size of mAbs compromise the efficacy of these ADCs. A more targeted approach is thus needed, and ADCs were designed to meet this need. However, in ADCs the method of conjugation of drug to antibody is >1, altering the structure of the drug which leads to off-target effects. Random conjugation also causes the drug to affect the pharmokinetics and biodistribution of the antibody and may cause nonspecific binding and internalization. Recombinant therapeutic proteins achieve controlled conjugation reactions and combine cytotoxicity and targeting in one molecule. They can also be engineered to extend half-life, stability and mechanism of action, and offer novel delivery routes. SNAP-tag fusion proteins are an example of a theranostic recombinant protein as they provide a unique antibody format to conjugate a variety of benzyl guanine modified labels, e.g. fluorophores and photosensitizers in a 1:1 stoichiometry. On the one hand, SNAP tag fusions can be used to optically image tumors when conjugated to a fluorophore, and on the other hand the recombinant proteins can induce necrosis/apoptosis in the tumor when conjugated to a photosensitizer upon exposure to a changeable wavelength of light. The dual nature of SNAP-tag fusions as both a diagnostic and therapeutic tool reinforces its significant role in cancer treatment in an era of precision medicine.

Selective Targeting of the L858R Mutation (EGFR) in Non-Small Cell Lung Cancer: A Mechanism for Advancing Targeted Chemotherapy

Lung cancer remains one of today’s most deadly and intractable cancers. Non-small cell lung cancer (NSCLC) accounts for roughly 85% of lung cancers, with an extremely poor survival rate. To ensure patient comfort and survival, the development of a selective therapy is imperative. However, lung cancer does not display surface proteins associated uniquely with tumor cells; thus, it is very difficult to develop a tumor-specific drug. Current techniques that target overexpression of proteins or inhibit growth pathways are either non-specific or prone to rapid drug resistance. The goal was to design a drug targeted to structural mutations expressed by tumor-associated general surface proteins, thereby combating the lack of tumor-unique markers in lung cancer. Mutant EGFR was identified as a potential target due to its prominence in tumor cells. Due to their size, it was determined that small molecules would be most effective at targeting isolated changes in protein structure, and thereby differentiating between the tumor-associated mutant EGFR and the healthy wild type. Conformational analysis of a virtual binding study conducted in VINA predicted a set of drug-like small molecules specific for the L858R mutation in EGFR. One molecule (ZN47) was then acquired and conjugated to a carrier protein to form a multifaceted hapten–protein conjugate. Multiple ELISAs were conducted to confirm the specificity of the conjugate to both tumor-associated mutant EGFRs. The results indicate that the identified molecule may be highly selective for tumor-associated L858R-EGFR, but further research, including a complete dosage-binding study, is necessary for full validation.

Targeted therapies in breast cancer: New challenges to fight against resistance

Breast cancer is the most common type of cancer found in women and today represents a significant challenge to public health. With the latest breakthroughs in molecular biology and immunotherapy, very specific targeted therapies have been tailored to the specific pathophysiology of different types of breast cancers. These recent developments have contributed to a more efficient and specific treatment protocol in breast cancer patients. However, the main challenge to be further investigated still remains the emergence of therapeutic resistance mechanisms, which develop soon after the onset of therapy and need urgent attention and further elucidation. What are the recent emerging molecular resistance mechanisms in breast cancer targeted therapy and what are the best strategies to apply in order to circumvent this important obstacle? The main scope of this review is to provide a thorough update of recent developments in the field and discuss future prospects for preventing resistance mechanisms in the quest to increase overall survival of patients suffering from the disease.

Regulation of angiogenic factors by the PI3K/Akt pathway in A549 lung cancer cells under hypoxic conditions

The aim of the present study was to investigate the influence of hypoxia and PI3K inhibition on angiogenic factors in A549 lung cancer cells. A549 cells were treated with the PI3K inhibitor LY294002 under normoxic and hypoxic conditions. Untreated cells were used as the control group and those treated by the inhibitor, as the suppression group. The cells were further divided based on normoxic or hypoxic conditions and named: Normoxic control group, normoxic suppression group, hypoxic control group and hypoxic suppression group. Expression levels of hypoxia-inducible factor (HIF)-1α and AKT1 mRNA in all groups were determined by reverse transcriptase-quantitative polymerase chain reaction and concentrations of vascular endothelial growth factor (VEGF), angiotensin II (ANG-II), transforming growth factor (TGF)-α/β1, and tumor necrosis factor (TNF)-α in the culture supernatant were measured by enzyme-linked immunosorbent assay. The expression levels of HIF-1α and AKT1 mRNA in the hypoxic control group were higher than those in the normoxic control group and the expression levels of HIF-1α and AKT1 mRNA in the hypoxic control group were higher than those in the hypoxic suppression group. Compared to the normoxic control and normoxic suppression groups, the concentrations of VEGF and TNF-α in supernatant were higher in the hypoxic control and hypoxic suppression groups, respectively. However, TGF-α and TGF-β1 demonstrated the opposite trend of the aforementioned factors. The concentration of ANG-II in the hypoxic suppression group was higher than that in the normoxic suppression group. In addition, compared to the normoxic control group and hypoxic control group, the concentrations of VEGF and TGF-β1 in supernatant were lower in the normoxic suppression group and in the hypoxic suppression group, respectively. In conclusion, the results of the present study suggest that hypoxia can stimulate A549 lung cancer cells to secrete VEGF and TNF-α and inhibit TGF-α and TGF-β1. The ability of A549 cells to secrete VEGF and TGF-β1 is regulated by PI3K/Akt, and ANG-II expression may be regulated by the PI3K/Akt pathway under hypoxic condition.

Retrospective review of genomic testing in breast cancer: Does it improve outcome?

PURPOSE

Tumor genomic testing has become widely available in many clinical settings. However, we do not yet understand how to best harness the information yielded from this testing. We retrospectively investigated the clinical courses of 24 patients who underwent tumor genomic testing to determine whether targeted therapy is associated with improved progression free survival (PFS) compared to standard therapy.

METHODS

The patient population comprised metastatic breast cancer patients who underwent tumor genomic testing (testing biopsy specimens of primary or metastatic lesions for 50 commonly mutated genes) at our institution between September 1, 2010 and June 1, 2015. Through retrospective chart review, we compared PFS for those patients who received targeted therapy based on their genomic testing results, and those who did not.

RESULTS

The median PFS was 5.7 months for those who received targeted therapy versus 5.4 months for those who did not (p = 0.6). There was no statistically significant difference in PFS between the two groups.

CONCLUSIONS

In this relatively small group, the PFS was markedly similar between the targeted therapy and standard therapy groups. Currently, there is no clear evidence to incorporate tumor genomic testing into routine clinical practice.

An update on the management of breast cancer in Africa

Background

There is limited information about the challenges of cancer management and attempts at improving outcomes in Africa. Even though South and North Africa are better resourceds to tackle the burden of breast cancer, similar poor prognostic factors are common to all countries. The five-year overall Survival rate for breast cancer patients does not exceed 60% for any low and middle-income country (LMIC) in Africa. In spite of the gains achieved over the past decade, certain characteristics remain the same such as limited availability of breast conservation therapies, inadequate access to drugs, few oncology specialists and adherence to harmful socio-cultural practices. This review on managing breast cancer in Africa is authored by African oncologists who practice or collaborate in Africa and with hands-on experience with the realities.

Methods

A search was performed via electronic databases from 1999 to 2016. (PubMed/Medline, African Journals Online) for all literature in English or translated into English, covering the terms “breast cancer in Africa and developing countries”. One hundred ninety were deemed appropriate.

Results

Breast tumors are diagnosed at earlier ages and later stages than in highincome countries. There is a higher prevalence of triple-negative cancers. The limitations of poor nursing care and surgery, inadequate access to radiotherapy, poor availability of basic and modern systemic therapies translate into lower survival rate. Positive strides in breast cancer management in Africa include increased adaptation of treatment guidelines, improved pathology services including immuno-histochemistry, expansion and upgrading of radiotherapy equipment across the continent in addition to more research opportunities.

Conclusion

This review is an update of the management of breast cancer in Africa, taking a look at the epidemiology, pathology, management resources, outcomes, research and limitations in Africa from the perspective of oncologists with local experience.

Yes1 signaling mediates the resistance to Trastuzumab/Lap atinib in breast cancer

Background

Overexpression of human epidermal growth factor receptor 2 (HER2) is observed in approximately 15–23% of breast cancers and these cancers are classified as HER2-positive breast cancer. Trastuzumab is the first-line targeted therapeutic drug for HER2-positive breast cancer and has improved patient overall survival. However, acquired resistance to trastuzumab is still a critical issue in breast cancer treatment. We previously established a trastuzumab-resistant breast cancer cell line (named as BT-474-R) from a trastuzumab-sensitive HER2-amplified cell line BT-474. Lapatinib is also a molecular-targeted drug for HER2-positive breast cancer, which acquired the resistance to trastuzumab. Acquired resistance to lapatinib is also an issue to be conquered.

Methods

We established trastuzumab/lapatinib-dual resistant cell line (named as BT-474-RL2) by additionally treating BT-474-R with lapatinib. We analyzed the mechanisms of resistance to trastuzumab and lapatinib. Besides, we analyzed the effect of the detected resistance mechanism in HER2-positive breast cancer patients.

Results

Proto-oncogene tyrosine-protein kinase Yes1, which is one of the Src family members, was amplified, overexpressed and activated in BT-474-R and BT-474-RL2. Silencing of Yes1 by siRNA induced both BT-474-R and BT-474-RL2 to restore the sensitivity to trastuzumab and lapatinib. Pharmaceutical inhibition of Yes1 by the Src inhibitor dasatinib was also effective to restore the sensitivity to trastuzumab and lapatinib in the two resistant cell lines. Combination treatment with dasatinib and trastuzumab induced down-regulation of signaling molecules such as HER2 and Akt. Moreover, the combination treatments induced G1-phase cell-cycle arrest and apoptosis. Consistent with cell line data, high expression of Yes1 mRNA was correlated with worse prognosis in patients with HER2-positive breast cancer.

Conclusion

Yes1 plays an important role in acquired resistance to trastuzumab and lapatinib in HER2-positive breast cancer. Our data suggest that pharmacological inhibition of Yes1 may be an effective strategy to overcome resistance to trastuzumab and lapatinib.

Novel Adamantanyl-Based Thiadiazolyl Pyrazoles Targeting EGFR in Triple-Negative Breast Cancer

The epidermal growth factor receptor (EGFR) is a validated therapeutic target for triple-negative breast cancer (TNBC). In the present study, we synthesize novel adamantanyl-based thiadiazolyl pyrazoles by introducing the adamantane ring to thiazolopyrazoline. On the basis of loss of cell viability in TNBC cells, 4-(adamantan-1-yl)-2-(3-(2,4-dichlorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl)thiazole (APP) was identified as a lead compound. Using a Parzen-Rosenblatt Window classifier, APP was predicted to target the EGFR protein, and the same was confirmed by surface plasmon resonance. Further analysis revealed that APP suppressed the phosphorylation of EGFR at Y992, Y1045, Y1068, Y1086, Y1148, and Y1173 in TNBC cells. APP also inhibited the phosphorylation of ERK at Y204 and of STAT3 at Y705, implying that APP downregulates the activity of EGFR downstream effectors. Small interfering RNA mediated depletion of EGFR expression prevented the effect of APP in BT549 and MDA-MB-231 cells, indicating that APP specifically targets the EGFR. Furthermore, APP modulated the expression of the proteins involved in cell proliferation and survival. In addition, APP altered the expression of epithelial-mesenchymal transition related proteins and suppressed the invasion of TNBC cells. Hence, we report a novel and specific inhibitor of the EGFR signaling cascade.

Molecular Mechanisms and Translational Therapies for Human Epidermal Receptor 2 Positive Breast Cancer

Breast cancer is the second leading cause of cancer death among women. Human epidermal receptor 2 (HER2) positive breast cancer (HER2+ BC) is the most aggressive subtype of breast cancer, with poor prognosis and a high rate of recurrence. About one third of breast cancer is HER2+ BC with significantly high expression level of HER2 protein compared to other subtypes. Therefore, HER2 is an important biomarker and an ideal target for developing therapeutic strategies for the treatment HER2+ BC. In this review, HER2 structure and physiological and pathological roles in HER2+ BC are discussed. Two diagnostic tests, immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH), for evaluating HER2 expression levels are briefly introduced. The current mainstay targeted therapies for HER2+ BC include monoclonal antibodies, small molecule tyrosine kinase inhibitors, antibody-drug conjugates (ADC) and other emerging anti-HER2 agents. In clinical practice, combination therapies are commonly adopted in order to achieve synergistic drug response. This review will help to better understand the molecular mechanism of HER2+ BC and further facilitate the development of more effective therapeutic strategies against HER2+ BC.

Safety of Combined Treatment With Monoclonal Antibodies and Viscum album L Preparations

Combination strategies involving chemotherapy and monoclonal antibodies (mAb) are commonly used in attempts to produce better clinical outcomes. This practice has led to new and ongoing toxicities that may lead to reductions in dose or noncompliance, limiting the effectiveness of treatment. Viscum album L (VA) preparations are widely used in Europe as additive therapy and have been associated with reduced chemotherapy-related adverse reactions and increased health-related quality of life. Concomitant VA therapy might also reduce toxicity related to mAb. This retrospective study investigated the safety of combined treatment with VA and mAb in cancer patients. A total of 43 patients had combined therapy (474 exposures); 12 had VA without mAb (129 exposures), and 8 had mAb without VA (68 exposures). Most patients (89.3%) received concomitant chemotherapy or supportive therapies. A total of 34 patients (60.7%) experienced 142 adverse events (AEs). Leucopenia (14.1% of all events), acneiform rash (8.5%), and stomatitis (6.3%) occurred most frequently. Longitudinal logistic regression analysis suggested a nearly 5 times higher odds of experiencing an AE following treatment with mAb compared with mAb plus VA (95% CI = 1.53-16.14). Our results, together with theoretical consideration of potential botanical-drug interactions, suggest that combined treatment with VA and mAb is safe.

Metabolic Imaging to Assess Treatment Response to Cytotoxic and Cytostatic Agents

For several decades, cytotoxic chemotherapeutic agents were considered the basis of anticancer treatment for patients with metastatic tumors. A decrease in tumor burden, assessed by volumetric computed tomography and magnetic resonance imaging, according to the response evaluation criteria in solid tumors (RECIST), was considered as a radiological response to cytotoxic chemotherapies. In addition to RECIST-based dimensional measurements, a metabolic response to cytotoxic drugs can be assessed by positron emission tomography (PET) using (18)F-fluoro-thymidine (FLT) as a radioactive tracer for drug-disrupted DNA synthesis. The decreased (18)FLT-PET uptake is often seen concurrently with increased apparent diffusion coefficients by diffusion-weighted imaging due to chemotherapy-induced changes in tumor cellularity. Recently, the discovery of molecular origins of tumorogenesis led to the introduction of novel signal transduction inhibitors (STIs). STIs are targeted cytostatic agents; their effect is based on a specific biological inhibition with no immediate cell death. As such, tumor size is not anymore a sensitive end point for a treatment response to STIs; novel physiological imaging end points are desirable. For receptor tyrosine kinase inhibitors as well as modulators of the downstream signaling pathways, an almost immediate inhibition in glycolytic activity (the Warburg effect) and phospholipid turnover (the Kennedy pathway) has been seen by metabolic imaging in the first 24 h of treatment. The quantitative imaging end points by magnetic resonance spectroscopy and metabolic PET (including 18F-fluoro-deoxy-glucose, FDG, and total choline) provide an early treatment response to targeted STIs, before a reduction in tumor burden can be seen.

Anticancer activity of an ultrasonic nanoemulsion formulation of Nigella sativa L. essential oil on human breast cancer cells

Nigella sativa L. (NS) is a plant renowned in traditional holistic medicine systems for almost 1400 years because of its remarkable antioxidant, antimicrobial, anti-inflammatory and anti-cancer properties. The essential oil of N. sativa, in particular, possesses these significant biological properties. However, N. sativa essential oil has many insoluble constituents with properties that have not been fully explored. Nanoemulsion-based insoluble formulations are a widely used carrier system for lipophilic materials. In the present study, we used ultrasonic emulsification, polysorbate 80 and water to formulate a highly stable N. sativa essential oil nanoemulsion (NSEO-NE). To optimize the NSEO-NE preparation, we changed the surfactant concentration, the oil-surfactant mixing ratio and the emulsification time. The droplet size distribution and morphology of the prepared NE was analyzed using dynamic light scattering and scanning electron microscopy, respectively. The droplet size of the NSEO-NE was approximately 20-50 nm in diameter. The anticancer properties of the NE preparation were studied using a modified methyl-thiazolyl-diphenyl tetrazolium bromide (MTT) assay as well as cellular uptake and nuclear morphological analyses. The NSEO-NE significantly reduced the viability of Michigan Cancer Foundation-7 (MCF-7) breast cancer cells. The nucleo-cytoplasmic morphological features of NSEO-NE-treated cells included cell membrane blebbing, cytoplasmic vacuolation, marginalization of chromatin, and fragmentation of the nucleus. The results clearly indicate that NSEO-NE induced apoptosis in MCF-7 cells. These findings support the potential application of NSEO-NE in breast cancer therapy, and also merit future translational research.

Erlotinib-induced purpuric papulopustular eruption treated with pulsed azithromycin

Erlotinib belongs to the targeted cancer treatments acting through epidermal growth factor receptor inhibition. Papulopustular eruption is the most common cutaneous toxicity. The pathogenesis of the rash is not clear. There is no consensus on treatment. In this report, we describe a 73-year-old female patient who was referred to our outpatient clinic for evaluation and treatment of a widespread acneiform eruption. She was put on erlotinib therapy for 3 months for the treatment of lung adenocarcinoma. The patient has developed nonpruritic papules and pustules widespread over the body except the face for the past 2 weeks. Bacterial culture obtained from a pustule on the back grew methicillin-sensitive Staphylococcus aureus (SA). Histopathological examination of a papule demonstrated vacuolar degeneration of basal layer, prominent walls of vessels, a mixed infiltration of eosinophils, and lymphocytes and erythrocyte extravasation. The eruption was successfully treated with two weekly pulses of azithromycin 500 mg for 3 consecutive days. This case demonstrated that erlotinib may cause purpuric papular eruption secondarily infected with SA. Routine bacterial culture should be performed from pustules before any treatment.

Inhibitor Response to HER2 G776(YVMA) In-frame Insertion in HER2-positive Breast Cancer

Human epidermal growth factor receptor 2 (HER2/neu or HER2) has long been recognized as an attractive therapeutic target for breast cancer. The YVMA in-frame insertion at the residue G776 (G776(YVMA)) of HER2 kinase domain is a frequently observed mutation that can largely shift drug sensitivity in targeted therapy of HER2-positive breast cancer. Here, the molecular mechanism and biological significance of tyrosine kinase inhibitor (TKI) response to HER2 G776(YVMA) insertion were investigated in detail. An established protocol that integrated bioinformatics modeling and kinase inhibition assay was employed to examine the structural basis, energetic property, and biological implication underlying the intermolecular interaction between HER2 kinase domain and three representative TKIs, i.e. two FDA-approved drugs lapatinib and gefitinib as well as a pan-kinase inhibitor staurosporine. It was found that the insertion mutation can moderately sensitize lapatinib, but cannot influence the inhibitory capability of staurosporine essentially, suggesting that the two inhibitors exhibit differentiated selectivity between the wild-type HER2 (HER2(WT)) and HER2 G776(YVMA) (HER2(YVMA)) variant. In addition, the gefitinib, which was originally developed as EGFR inhibitor, only possesses modest potency against its noncogate target HER2(WT), and the insertion can further impair the potency, causing a strong resistance for the agent to HER2(YVMA) variant.

NRBP1 is downregulated in breast cancer and NRBP1 overexpression inhibits cancer cell proliferation through Wnt/β-catenin signaling pathway

Nuclear receptor binding protein 1 (NRBP1) is a highly conserved protein that is ubiquitously expressed across cell types in humans. NRBP1 has been recently identified as an adaptor protein. It has been suggested that it plays important roles in cellular homeostasis and the pathophysiology of cancer. To determine whether NRBP1 is involved in the pathophysiology of breast cancer, we performed a correlation study between the expression level of NRBP1 and the clinicopathological features in 92 breast cancer patients. A strong correlation was detected between NRBP1 expression and advanced histopathology grades, tumor, node, and metastasis stage, tumor diameter, lymph node involvement, as well as the recurrence of breast cancer in 92 tested patients. The tumor tissues from patients also expressed lower NRBP1 than did adjacent healthy tissues. Furthermore, we overexpressed NRBP1 in MCF-7 and MDA-MB-231 breast cancer cell lines and found NRBP1 upregulation-inhibited cell proliferation by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Blocking the autocrine Wnt signaling pathway by LGK974 could remove the NRBP1-overexpression-induced inhibition in breast cancer cells. The results of this study suggest that NRBP1 plays a tumor-suppressive role in breast cancer pathophysiology, which likely acts through the Wnt/β-catenin signaling pathway.

Potential role for mammalian target of rapamycin inhibitors as first-line therapy in hormone receptor-positive advanced breast cancer

Despite advances in cytotoxic chemotherapy and targeted therapies, 5-year survival rates remain low for patients with advanced breast cancer at diagnosis. This highlights the limited effectiveness of current treatment options. An improved understanding of cellular functions associated with the development and progression of breast cancer has resulted in the creation of a number of novel targeted molecular therapies. However, more work is needed to improve outcomes, particularly in the first-line recurrent or metastatic hormone receptor-positive breast cancer setting. The phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (mTOR) pathway is a major intracellular signaling pathway that is often upregulated in breast cancer, and overactivation of this pathway has been associated with primary or developed resistance to endocrine treatment. Clinical data from the Phase III Breast Cancer Trials of Oral Everolimus-2 (BOLERO-2) study of the mTOR inhibitor everolimus combined with exemestane in hormone receptor-positive advanced breast cancer were very promising, highlighting the potential role of mTOR inhibitors in combination with endocrine therapies as a first-line treatment option for these patients. It is hoped that the use of mTOR inhibitors combined with current standard-of-care endocrine therapies, such as aromatase inhibitors, in the first-line advanced breast cancer setting may result in greater antitumor effects and also delay or reverse treatment resistance.

Treating Elderly Patients With Hormone Receptor-Positive Advanced Breast Cancer

As the overall population ages, the proportion of elderly patients (aged ≥65 years) with breast cancer also increases. Studies have shown that elderly patients with hormone receptor–positive breast cancer can derive as much benefit from treatment as do younger patients, yet they remain underrepresented in clinical trials and are often undertreated in clinical practice. Treatment decisions for older patients should not be based solely on chronologic age; a patient’s physiologic functioning and comorbidities must also be taken into consideration. For recurrent or metastatic disease, systemic treatment with endocrine therapies or chemotherapy may prolong a patient’s life and alleviate troublesome symptoms. Resistance to therapy remains a problem in the advanced breast cancer setting, with most patients eventually becoming resistant to additional treatment. New combination regimens that target multiple pathways, such as everolimus plus exemestane, have shown efficacy in elderly patients previously resistant to endocrine therapies, and future research may need to focus on such combinations in order to improve outcomes in this patient group. A number of investigational agents are in clinical development, although few studies identify their effects in the elderly patient population. Optimizing effective yet tolerable therapeutic regimens for elderly patients could improve their outcomes while ensuring that the goals of improved survival and quality of life are considered.

Thioaptamer-conjugated CD44-targeted delivery system for the treatment of breast cancer in vitro and in vivo

The high transfection efficiency and enhanced therapeutic effect of drug delivery systems developed in recent years imply that ligand-decorated nanocarriers are potentially targeted vectors for breast cancer treatment. Thioaptamer (TA)-modified nanoparticles (NPs) designed in this study mainly consisted of ligand TA and dendritic polyamidoamine (PAMAM). Knowing that TA can bind to CD44-receptors in breast cancer, this study was intended to validate the safety and feasibility of systemic miRNA delivery to breast cancer cells by TA-PEG-PAMAM/miRNA (polyethylene glycol - PEG), testify its tumor targeting efficiency in vitro, and observe its biodistribution when it was administered systemically to a xenograft mouse model of breast cancer. The in vivo and ex vivo imaging results in human breast cancer tumor-bearing mice showed that TA-modification was able to enhance the accumulation of NPs in the breast cancer tumor. Our data showed that TA-NPs did not induce functional impairment to normal tissues and vital organs. TA-NPs may prove to be a safe and effective miRNA deliver system for breast cancer treatment, and could be widely used in pre-clinical and eventually clinical arenas of breast cancer treatment.

Transforming growth factor-β, insulin-like growth factor I/insulin-like growth factor I receptor and vascular endothelial growth factor-A: prognostic and predictive markers in triple-negative and non-triple-negative breast cancer

In the current study, the prognostic and predictive values of serum transforming growth factor-β1 (TGF-β1), insulin-like growth factor I (IGF-I)/IGF-I receptor (IGF-IR) and vascular endothelial growth factor-A (VEGF-A) were evaluated in triple-negative and non-triple-negative breast cancer (TNBC and non-TNBC). The aim was to identify a group of serological biomarkers and to identify possible candidates for targeted therapy in patients with TNBC and non-TNBC. Protein levels of TGF-β1, IGF-I/IGF-IR and VEGF-A in the serum were measured in 43 TNBC, 53 non-TNBC and 20 normal control participants using quantitative ELISA assays. Results were correlated against standard prognostic factors, response to treatment and survival. TNBC was identified to be associated with poor prognosis and serum levels of VEGF-A and IGF/IGF-IR were significantly higher in the TNBC group compared with the non-TNBC group. IGF-IR and VEGF-A overexpression was observed to be correlated with TGF-β1 expression and all of the markers investigated were associated with metastasis and disease progression. In the multivariate analysis, VEGF-A, IGF-I and IGF-IR were observed to be independent predictors for overall survival, whereas TGF-β1 and lymph node status were identified as independent predictors for disease-free survival. The overall response rate was significantly lower in patients with TNBC and those with high levels of TGF-β1, IGF-I/IGF-IR and VEGF-A. In view of the present results, it was concluded that TGF-β1, IGF-I/IGF-IR and VEGF-A overexpression is associated with the presence of aggressive tumors, which exhibit an increased probability of metastasis, a poor response to treatment and reduced survival rate. This indicates that VEGF-A, IGF-IR and IGF-I have the potential to be used as surrogate biomarkers and are promising candidates for targeted therapy, particularly in patients with TNBC.

Using Boolean Logic Modeling of Gene Regulatory Networks to Exploit the Links Between Cancer and Metabolism for Therapeutic Purposes

The uncontrolled cell proliferation that is characteristically associated with cancer is usually accompanied by alterations in the genome and cell metabolism. Indeed, the phenomenon of cancer cells metabolizing glucose using a less efficient anaerobic process even in the presence of normal oxygen levels, termed the Warburg effect, is currently considered to be one of the hallmarks of cancer. Diabetes, much like cancer, is defined by significant metabolic changes. Recent epidemiological studies have shown that diabetes patients treated with the antidiabetic drug Metformin have significantly lowered risk of cancer as compared to patients treated with other antidiabetic drugs. We utilize a Boolean logic model of the pathways commonly mutated in cancer to not only investigate the efficacy of Metformin for cancer therapeutic purposes but also demonstrate how Metformin in concert with other cancer drugs could provide better and less toxic clinical outcomes as compared to using cancer drugs alone.

microRNA-194 suppresses osteosarcoma cell proliferation and metastasis in vitro and in vivo by targeting CDH2 and IGF1R

Studies have shown that miR-194 functions as a tumor suppressor and is associated with tumor growth and metastasis. We studied the effects of miR-194 in osteosarcoma and the possible mechanism by which miR-194 affected the survival, apoptosis and metastasis of osteosarcoma. Both human osteosarcoma cell lines SOSP-9607 and U2-OS were transfected with recombinant lentiviruses to regulate miR-194 expression. Overexpression of miR-194 partially inhibited the proliferation, migration, and invasion of osteosarcoma cells in vitro, as well as tumor growth and pulmonary metastasis of osteosarcoma cells in vivo. Potential miR-194 target genes were predicted using bioinformatics. Luciferase reporter assay, real-time quantitative PCR and western blotting confirmed that CDH2 (N-cadherin) and IGF1R were targets of miR-194. Using real-time quantitative PCR, we evaluated the expression of miR-194 and two miR-194 target genes, CDH2 and IGF1R in osteosarcoma samples from 107 patients and 99 formalin- or paraformalin-fixed paraffin-embedded tissues. The expressions of the target genes were also examined in osteosarcoma samples using immunohistochemistry. Overexpression of miR-194 inhibited tumor growth and metastasis of osteosarcoma probably by downregulating CDH2 and IGF1R. miR-194 may prove to be a promising therapeutic agent for osteosarcoma.