Chemoresistance mechanisms of breast cancer and their countermeasures. Biomed Pharmacother. 2019;114:108800. [PMID: 30921705 DOI: 10.1016/j.biopha.2019.108800]

A mathematical model for predicting the spatiotemporal response of breast cancer cells treated with doxorubicin

Tumor heterogeneity contributes significantly to chemoresistance, a leading cause of treatment failure. To better personalize therapies, it is essential to develop tools capable of identifying and predicting intra- and inter-tumor heterogeneities. Biology-inspired mathematical models are capable of attacking this problem, but tumor heterogeneity is often overlooked in in-vivo modeling studies, while phenotypic considerations capturing spatial dynamics are not typically included in in-vitro modeling studies. We present a data assimilation-prediction pipeline with a two-phenotype model that includes a spatiotemporal component to characterize and predict the evolution of in-vitro breast cancer cells and their heterogeneous response to chemotherapy. Our model assumes that the cells can be divided into two subpopulations: surviving cells unaffected by the treatment, and irreversibly damaged cells undergoing treatment-induced death. MCF7 breast cancer cells were previously cultivated in wells for up to 1000 hours, treated with various concentrations of doxorubicin and imaged with time-resolved microscopy to record spatiotemporally-resolved cell count data. Images were used to generate cell density maps. Treatment response predictions were initialized by a training set and updated by weekly measurements. Our mathematical model successfully calibrated the spatiotemporal cell growth dynamics, achieving median [range] concordance correlation coefficients of > .99 [.88, >.99] and .73 [.58, .85] across the whole well and individual pixels, respectively. Our proposed data assimilation-prediction approach achieved values of .97 [.44, >.99] and .69 [.35, .79] for the whole well and individual pixels, respectively. Thus, our model can capture and predict the spatiotemporal dynamics of MCF7 cells treated with doxorubicin in an in-vitro setting.

Osteopontin: A Key Multifaceted Regulator in Tumor Progression and Immunomodulation

The tumor microenvironment (TME) is composed of various cellular components such as tumor cells, stromal cells including fibroblasts, adipocytes, mast cells, lymphatic vascular cells and infiltrating immune cells, macrophages, dendritic cells and lymphocytes. The intricate interplay between these cells influences tumor growth, metastasis and therapy failure. Significant advancements in breast cancer therapy have resulted in a substantial decrease in mortality. However, existing cancer treatments frequently result in toxicity and nonspecific side effects. Therefore, improving targeted drug delivery and increasing the efficacy of drugs is crucial for enhancing treatment outcome and reducing the burden of toxicity. In this review, we have provided an overview of how tumor and stroma-derived osteopontin (OPN) plays a key role in regulating the oncogenic potential of various cancers including breast. Next, we dissected the signaling network by which OPN regulates tumor progression through interaction with selective integrins and CD44 receptors. This review addresses the latest advancements in the roles of splice variants of OPN in cancer progression and OPN-mediated tumor-stromal interaction, EMT, CSC enhancement, immunomodulation, metastasis, chemoresistance and metabolic reprogramming, and further suggests that OPN might be a potential therapeutic target and prognostic biomarker for the evolving landscape of cancer management.

Recent advanced lipid-based nanomedicines for overcoming cancer resistance

The increasing prevalence of cancer drug resistance not only critically limits the efficiency of traditional therapies but also causes relapses or recurrences of cancer. Consequently, there remains an urgent need to address the intricate landscape of drug resistance beyond traditional cancer therapies. Recently, nanotechnology has played an important role in the field of various drug delivery systems for the treatment of cancer, especially therapy-resistant cancer. Among advanced nanomedicine technologies, lipid-based nanomaterials have emerged as effective drug carriers for cancer treatment, significantly improving therapeutic effects. Due to their biocompatibility, simplicity of preparation, and potential for functionalization, lipid-based nanomaterials are considered powerful competitors for resistant cancer. In this review, an overview of lipid-based nanomaterials for addressing cancer resistance is discussed. We summarize the recent progress in overcoming drug resistance in cancer by these lipid-based nanomaterials, and highlight their potential in future applications to reverse cancer resistance.

A prismatic view of the epigenetic-metabolic regulatory axis in breast cancer therapy resistance

Epigenetic regulation established during development to maintain patterns of transcriptional expression and silencing for metabolism and other fundamental cell processes can be reprogrammed in cancer, providing a molecular mechanism for persistent alterations in phenotype. Metabolic deregulation and reprogramming are thus an emerging hallmark of cancer with opportunities for molecular classification as a critical preliminary step for precision therapeutic intervention. Yet, acquisition of therapy resistance against most conventional treatment regimens coupled with tumor relapse, continue to pose unsolved problems for precision healthcare, as exemplified in breast cancer where existing data informs both cancer genotype and phenotype. Furthermore, epigenetic reprograming of the metabolic milieu of cancer cells is among the most crucial determinants of therapeutic resistance and cancer relapse. Importantly, subtype-specific epigenetic-metabolic interplay profoundly affects malignant transformation, resistance to chemotherapy, and response to targeted therapies. In this review, we therefore prismatically dissect interconnected epigenetic and metabolic regulatory pathways and then integrate them into an observable cancer metabolism-therapy-resistance axis that may inform clinical intervention. Optimally coupling genome-wide analysis with an understanding of metabolic elements, epigenetic reprogramming, and their integration by metabolic profiling may decode missing molecular mechanisms at the level of individual tumors. The proposed approach of linking metabolic biochemistry back to genotype, epigenetics, and phenotype for specific tumors and their microenvironment may thus enable successful mechanistic targeting of epigenetic modifiers and oncometabolites despite tumor metabolic heterogeneity.

Hyaluronic acid-oleylamine and chitosan-oleic acid conjugate-based hybrid nanoparticle delivery via. dissolving microneedles for enhanced treatment efficacy in localized breast cancer

Microneedle technology offers a minimally invasive treatment strategy to deliver chemotherapeutics to localized tumors. Amalgamating the surface functionalized nanoparticles with microneedle technology can potentially deliver drugs directly to tumors and subsequently target cancer cells via, overexpressed receptors on the cell surface, thereby enhancing the treatment efficacy while reducing side effects. Here, we report cetuximab anchored hyaluronic acid-oleylamine and chitosan-oleic acid-based hybrid nanoparticle (HA-OA/CS-OA NPT)-loaded dissolving microneedles (MN) for targeted delivery of cabazitaxel (CBT) in localized breast cancer tumor. The HA-OA/CS-OA NPT was characterized for their size, surface charge, morphology, physicochemical characteristics, drug release behavior, and in vitro anti-cancer efficacy. The HA-OA/CS-OA NPT were of ~125 nm size, showed enhanced cytotoxicity and cellular uptake, and elicited a superior apoptotic response against MDA-MB-231 cells. Subsequently, the morphology and physicochemical characteristics of HA-OA/CS-OA NPT-loaded MN were also evaluated. The fabricated microneedles were of ~550 μm height and showed loading of nanoparticles equivalent to ~250 μg of CBT. The ex vivo skin permeation study revealed fast dissolution of microneedles upon hydration, while the drug permeation across the skin exhibited ~4-fold improvement in comparison to free drug-loaded MN. In vivo studies performed on DMBA-induced breast cancer in female SD rats showed a marked reduction in tumor volume after administration of drug and nanoparticle-loaded microneedles in comparison to intravenous administration of free drug. However, the HA-OA/CS-OA NPT-MN showed the highest tumor reduction and survival rate, with the lowest body weight reduction in comparison to other treatment groups, indicating its superior efficacy and low systemic toxicity. Overall, the dissolving microneedle-mediated delivery of targeted nanoparticles loaded with chemotherapeutics offers a superior alternative to conventional intravenous chemotherapy.

AQP3 and AQP5 Modulation in Response to Prolonged Oxidative Stress in Breast Cancer Cell Lines

Aquaporins are membrane pores regulating the transport of water, glycerol, and other small molecules across membranes. Among 13 human aquaporins, six have been shown to transport H2O2 and are therefore called peroxiporins. Peroxiporins are implicated in cancer development and progression, partly due to their involvement in H2O2 transport. Oxidative stress is linked to breast cancer development but is also a mechanism of action for conventional chemotherapy. The aim of this study is to investigate the effects of prolonged oxidative stress on Aquaporin 3 (AQP3), Aquaporin 5 (AQP5), and signaling pathways in breast cancer cell lines of different malignancies alongside a non-tumorigenic breast cell line. The prolonged oxidative stress caused responses in viability only in the cancer cell lines, while it affected cell migration in the MCF7 cell line. Changes in the localization of NRF2, a transcription factor involved in oxidative stress response, were observed only in the cancer cell lines, and no effects were recorded on its downstream target proteins. Moreover, the prolonged oxidative stress caused changes in AQP3 and AQP5 expression only in the cancer cell lines, in contrast to their non-malignant counterparts. These results suggest peroxiporins are potential therapeutic targets in cancer treatment. However, further research is needed to elucidate their role in the modulation of therapy response, highlighting the importance of research on this topic.

Design and Evaluation of NSAID Derivatives as AKR1C3 Inhibitors for Breast Cancer Treatment through Computer-Aided Drug Design and In Vitro Analysis

Breast cancer is a major global health issue, causing high incidence and mortality rates as well as psychological stress for patients. Chemotherapy resistance is a common challenge, and the Aldo-keto reductase family one-member C3 enzyme is associated with resistance to anthracyclines like doxorubicin. Recent studies have identified celecoxib as a potential treatment for breast cancer. Virtual screening was conducted using a quantitative structure-activity relationship model to develop similar drugs; this involved backpropagation of artificial neural networks and structure-based virtual screening. The screening revealed that the C-6 molecule had a higher affinity for the enzyme (-11.4 kcal/mol), a lower half-maximal inhibitory concentration value (1.7 µM), and a safer toxicological profile than celecoxib. The compound C-6 was synthesized with an 82% yield, and its biological activity was evaluated. The results showed that C-6 had a more substantial cytotoxic effect on MCF-7 cells (62%) compared to DOX (63%) and celecoxib (79.5%). Additionally, C-6 had a less harmful impact on healthy L929 cells than DOX and celecoxib. These findings suggest that C-6 has promising potential as a breast cancer treatment.

Lung-derived soluble factors support stemness/plasticity and metastatic behaviour of breast cancer cells via the FGF2-DACH1 axis

Patients with triple-negative breast cancer (TNBC) have an increased propensity to develop lung metastasis. Our previous studies demonstrated that stem-like ALDHhiCD44+ breast cancer cells interact with lung-derived soluble factors, resulting in enhanced migration and lung metastasis particularly in TNBC models. We have also observed that the presence of a primary TNBC tumor can 'prime' the lung microenvironment in preparation for metastasis. In this study, we hypothesized that soluble lung-derived factors secreted in the presence of a primary TNBC tumor can influence stemness/plasticity of breast cancer cells. Using an ex vivo pulmonary metastasis assay (PuMA), we observed that the lung microenvironment supports colonization and growth of ALDHhiCD44+ TNBC cells, potentially via interactions with lung-derived FGF2. Exposure of TNBC cells to lung-conditioned media (LCM) generated from mice bearing TNBC primary tumors (tbLCM) significantly enhanced the proportion of ALDHhiCD44+ cells compared to control or LCM from tumor-naïve mice (tnLCM). Further analysis using a human cancer stem cell qPCR array revealed that, relative to tnLCM or control, exposure of TNBC cells to tbLCM leads to downregulation of the transcription factor and putative tumor suppressor Dachshund homolog 1 (DACH1), a downstream regulator of FGF2. In addition, inhibition of DACH1 using siRNA or treatment with recombinant FGF2 enhanced the ALDHhiCD44+ phenotype. Taken together, our findings suggest that the FGF2-DACH1 signaling axis supports stemness/plasticity of TNBC cells in the lung microenvironment and lays the foundation for future evaluation of FGF2 as a potential novel therapeutic target for treatment or prevention of breast cancer metastasis to the lung.

Diagnostic, prognostic, and therapeutic potential of exosomal microRNAs in renal cancer

Renal cell carcinoma (RCC) arises from the tubular epithelial cells of the nephron. It has the highest mortality rate among urological cancers. There are no effective therapeutic approaches and no non-invasive biomarkers for diagnosis and follow-up. Thus, suitable novel biomarkers and therapeutic targets are essential for improving RCC diagnosis/prognosis and treatment. Circulating exosomes such as exosomal microRNAs (Exo-miRs) provide non-invasive prognostic/diagnostic biomarkers and valuable therapeutic targets, as they can be easily isolated and quantified and show high sensitivity and specificity. Exosomes secreted by an RCC can exhibit alterations in the miRs' profile that may reflect the cellular origin and (patho)physiological state, as a ''signature'' or ''fingerprint'' of the donor cell. It has been shown that the transportation of renal-specific miRs in exosomes can be rapidly detected and measured, holding great potential as biomarkers in RCC. The present review highlights the studies reporting tumor microenvironment-derived Exo-miRs with therapeutic potential as well as circulating Exo-miRs as potential diagnostic/prognostic biomarkers in patients with RCC.

FBXO8 is a novel prognostic biomarker in different molecular subtypes of breast cancer and suppresses breast cancer progression by targeting c-MYC

F-box only protein 8 (FBXO8) is a recently identified member of the F-box proteins, showcasing its novelty in this protein family. Extensive research has established FBXO8's role as a tumor suppressor in various cancers, including hepatocellular carcinoma, and colorectal cancer, Nevertheless, its functional, mechanistic, and prognostic roles in primary and metastatic breast cancer, particularly in different molecular subtypes of breast cancer, various stages, as well as its potential implications in immunotherapy, tumor microenvironment, and prognostic survival among breast cancer patients, remain unexplored. In this article, we employed a multi-dimensional investigation leveraging TCGA, TIMER, TISIDB, STRING, MEXPRESS, UALCAN, and cBioPortal databases to explore the underlying suppression mechanism of FBXO8 in breast cancer. FBXO8 negatively correlates with MYC, NOTCH, WNT and inflammatory signaling pathways in breast tumor microenvironment. Furthermore we conducted RT-PCR, western blot, cell proliferation, cell migration, and mRNA target gene RT-PCR analyses to elucidate the role of FBXO8 in breast cancer progression. Mechanistically, PTEN and FBXW7 expression were down-regulated and MYC, IL10, IL6, NOTCH1, WNT6 mRNA expressions were up-regulated in FBXO8 knockdown cell lines. c-MYC silenced cells showed an increase in FBXO8 protein level, which suggests a negative feedback loop between FBXO8 and c-MYC to control breast cancer metastasis. These findings illuminate the novel role of FBXO8 as a prognostic and therapeutic target across different molecular subtypes of breast cancer. Finally, through the utilization of virtual screening and Molecular Dynamics simulations, we successfully identified two FDA-approved medications, Ledipasvir and Paritaprevir, that demonstrated robust binding capabilities and interactions with FBXO8.

Novel naphthoquinone-1H-1,2,3-triazole hybrids: Design, synthesis and evaluation as inductors of ROS-mediated apoptosis in the MCF-7 cells

The search for novel anticancer drugs is essential to expand treatment options, overcome drug resistance, reduce toxicity, promote innovation, and tackle the economic impact. The importance of these studies lies in their contribution to advancing cancer research and enhancing patient outcomes in the battle against cancer. Here, we developed new asymmetric hybrids containing two different naphthoquinones linked by a 1,2,3-1H-triazole nucleus, which are potential new drugs for cancer treatment. The antitumor activity of the novel compounds was tested using the breast cancer cell lines MCF-7 and MDA-MB-231, using the non-cancer cell line MCF10A as control. Our results showed that two out of twenty-two substances tested presented potential antitumor activity against the breast cancer cell lines. These potential drugs, named here 12g and 12h were effective in reducing cell viability and promoting cell death of the tumor cell lines, exhibiting minimal effects on the control cell line. The mechanism of action of the novel drugs was assessed revealing that both drugs increased reactive oxygen species production with consequent activation of the AMPK pathway. Therefore, we concluded that 12g and 12h are novel AMPK activators presenting selective antitumor effects.

Deciphering the oncogenic landscape: Unveiling the molecular machinery and clinical significance of LncRNA TMPO-AS1 in human cancers

The in-depth exploration of long non-coding RNAs (lncRNAs) reveals their pivotal and diverse roles in various disorders, particularly cancer. Within this intricate landscape, thymopoietin-antisense RNA-1 (TMPO-AS1) emerges as a noteworthy instigator of oncogenesis in humans. This exhaustive review seeks to intricately unravel the present understanding of TMPO-AS1, emphasizing its molecular foundations and highlighting its clinical applications in the realm of cancer research. TMPO-AS1 consistently exhibits heightened expression across a spectrum of cancer types, encompassing lung, colorectal, breast, cervical, bladder, pancreatic, hepatocellular, gastric, ovarian, and osteosarcoma. Elevated levels of TMPO-AS1 are intricately linked to unfavorable prognoses, accompanied by distinctive clinical and pathological characteristics. Functionally, TMPO-AS1 showcases its prowess in enhancing cancer cell migration, invasion, proliferation, and orchestrating epithelial-mesenchymal transition (EMT) through a myriad of molecular mechanisms. These mechanisms entail intricate interactions with proteins, microRNAs, and intricate signaling pathways. Furthermore, TMPO-AS1 is intricately involved in regulating critical cellular processes, including apoptosis and the cell cycle. The mounting evidence converges towards the potential of TMPO-AS1 serving as a diagnostic and prognostic biomarker, further entwined with its potential role in influencing chemoresistance in cancer. This potential is underscored by its consistent associations with clinical outcomes and treatment responses. This comprehensive investigation not only consolidates our existing knowledge of TMPO-AS1's multifaceted roles but also sheds illuminating insights on its profound significance in the intricate landscape of cancer biology, paving the way for potential applications in clinical practice.

miR-125 in Breast Cancer Etiopathogenesis: An Emerging Role as a Biomarker in Differential Diagnosis, Regenerative Medicine, and the Challenges of Personalized Medicine

Breast Cancer (BC) is one of the most common cancer types worldwide, and it is characterized by a complex etiopathogenesis, resulting in an equally complex classification of subtypes. MicroRNA (miRNA or miR) are small non-coding RNA molecules that have an essential role in gene expression and are significantly linked to tumor development and angiogenesis in different types of cancer. Recently, complex interactions among coding and non-coding RNA have been elucidated, further shedding light on the complexity of the roles these molecules fulfill in cancer formation. In this context, knowledge about the role of miR in BC has significantly improved, highlighting the deregulation of these molecules as additional factors influencing BC occurrence, development and classification. A considerable number of papers has been published over the past few years regarding the role of miR-125 in human pathology in general and in several types of cancer formation in particular. Interestingly, miR-125 family members have been recently linked to BC formation as well, and complex interactions (competing endogenous RNA networks, or ceRNET) between this molecule and target mRNA have been described. In this review, we summarize the state-of-the-art about research on this topic.

Unveiling the mechanisms and challenges of cancer drug resistance

Cancer treatment faces many hurdles and resistance is one among them. Anti-cancer treatment strategies are evolving due to innate and acquired resistance capacity, governed by genetic, epigenetic, proteomic, metabolic, or microenvironmental cues that ultimately enable selected cancer cells to survive and progress under unfavorable conditions. Although the mechanism of drug resistance is being widely studied to generate new target-based drugs with better potency than existing ones. However, due to the broader flexibility in acquired drug resistance, advanced therapeutic options with better efficacy need to be explored. Combination therapy is an alternative with a better success rate though the risk of amplified side effects is commonplace. Moreover, recent groundbreaking precision immune therapy is one of the ways to overcome drug resistance and has revolutionized anticancer therapy to a greater extent with the only limitation of being individual-specific and needs further attention. This review will focus on the challenges and strategies opted by cancer cells to withstand the current therapies at the molecular level and also highlights the emerging therapeutic options -like immunological, and stem cell-based options that may prove to have better potential to challenge the existing problem of therapy resistance. Video Abstract.

The role of Aquaporins in tumorigenesis: implications for therapeutic development

Aquaporins (AQPs) are ubiquitous channel proteins that play a critical role in the homeostasis of the cellular environment by allowing the transit of water, chemicals, and ions. They can be found in many different types of cells and organs, including the lungs, eyes, brain, glands, and blood vessels. By controlling the osmotic water flux in processes like cell growth, energy metabolism, migration, adhesion, and proliferation, AQPs are capable of exerting their regulatory influence over a wide range of cellular processes. Tumour cells of varying sources express AQPs significantly, especially in malignant tumours with a high propensity for metastasis. New insights into the roles of AQPs in cell migration and proliferation reinforce the notion that AQPs are crucial players in tumour biology. AQPs have recently been shown to be a powerful tool in the fight against pathogenic antibodies and metastatic cell migration, despite the fact that the molecular processes of aquaporins in pathology are not entirely established. In this review, we shall discuss the several ways in which AQPs are expressed in the body, the unique roles they play in tumorigenesis, and the novel therapeutic approaches that could be adopted to treat carcinoma.

Combination of Resveratrol and PARP inhibitor Olaparib efficiently deregulates homologous recombination repair pathway in breast cancer cells through inhibition of TIP60-mediated chromatin relaxation

Recently, we reported that a combination of a natural, bioactive compound Resveratrol (RES) and a PARP inhibitor Olaparib (OLA) deregulated the homologous recombination (HR) pathway, and enhanced apoptosis in BRCA1-wild-type, HR-proficient breast cancer cells. Upon DNA damage, chromatin relaxation takes place, which allows the DNA repair proteins to access the DNA lesion. But whether chromatin remodeling has any role in RES + OLA-mediated HR inhibition is not known. By using in vitro and ex vivo model systems of breast cancer, we have investigated whether RES + OLA inhibits chromatin relaxation and thereby blocks the HR pathway. It was found that RES + OLA inhibited PARP1 activity, terminated PARP1-BRCA1 interaction, and deregulated the HR pathway only in the chromatin fraction of MCF-7 cells. DR-GFP reporter plasmid-based HR assay demonstrated marked reduction in HR efficiency in I-SceI endonuclease-transfected cells treated with OLA. RES + OLA efficiently trapped PARP1 at the DNA damage site in the chromatin of MCF-7 cells. Unaltered expressions of HR proteins were found in the chromatin of PARP1-silenced MCF-7 cells, which confirmed that RES + OLA-mediated DNA damage response was PARP1-dependent. Histone Acetyltransferase (HAT) activity and histone H4 acetylation assays showed reduction in HAT activity and H4 acetylation in RES + OLA-treated chromatin fraction of cells. Western blot analysis showed that the HAT enzyme TIP60, P400 and acetylated H4 were downregulated after RES + OLA exposure. In the co-immunoprecipitation assay, it was observed that RES + OLA caused abolition of PARP1-TIP60-BRCA1 interaction, which suggested the PARP1-dependent TIP60-BRCA1 association. Unaltered expressions of PAR, BRCA1, P400, and acetylated H4 in the chromatin of TIP60-silenced MCF-7 cells further confirmed the role of TIP60 in PARP1-mediated HR activation in the chromatin. Similar results were obtained in ex vivo patient-derived primary breast cancer cells. Thus, the present study revealed that RES + OLA treatment inhibited PARP1 activity in the chromatin, and blocked TIP60-mediated chromatin relaxation, which, in turn, affected PARP1-dependent TIP60-BRCA1 association, resulting in deregulation of HR pathway in breast cancer cells.

Predictive, preventive, and personalized medicine in breast cancer: targeting the PI3K pathway

Breast cancer (BC) is a multifaceted disease characterized by distinct molecular subtypes and varying responses to treatment. In BC, the phosphatidylinositol 3-kinase (PI3K) pathway has emerged as a crucial contributor to the development, advancement, and resistance to treatment. This review article explores the implications of the PI3K pathway in predictive, preventive, and personalized medicine for BC. It emphasizes the identification of predictive biomarkers, such as PIK3CA mutations, and the utility of molecular profiling in guiding treatment decisions. The review also discusses the potential of targeting the PI3K pathway for preventive strategies and the customization of therapy based on tumor stage, molecular subtypes, and genetic alterations. Overcoming resistance to PI3K inhibitors and exploring combination therapies are addressed as important considerations. While this field holds promise in improving patient outcomes, further research and clinical trials are needed to validate these approaches and translate them into clinical practice.

Liposomal Nano-Based Drug Delivery Systems for Breast Cancer Therapy: Recent Advances and Progresses

Breast cancer is a highly prevalent disease on a global scale, with a 30% incidence rate among women and a 14% mortality rate. Developing countries bear a disproportionate share of the disease burden, while countries with greater technological advancements exhibit a higher incidence. A mere 7% of women under the age of 40 are diagnosed with breast cancer, and the prevalence of this ailment is significantly diminished among those aged 35 and younger. Chemotherapy, radiation therapy, and surgical intervention comprise the treatment protocol. However, the ongoing quest for a definitive cure for breast cancer continues. The propensity for cancer stem cells to metastasize and resistance to treatment constitute their Achilles' heel. The advancement of drug delivery techniques that target cancer cells specifically holds significant promise in terms of facilitating timely detection and effective intervention. Novel approaches to pharmaceutical delivery, including nanostructures and liposomes, may bring about substantial changes in the way breast cancer is managed. These systems offer a multitude of advantages, such as heightened bioavailability, enhanced solubility, targeted tumor destruction, and diminished adverse effects. The application of nano-drug delivery systems to administer anti-breast cancer medications is a significant subject of research. This article delves into the domain of breast cancer, conventional treatment methods, the incorporation of nanotechnology into managerial tactics, and strategic approaches aimed at tackling the disease at its core.

pH-Responsive Polypropylene Sulfide Magnetic Nanocarrier-Mediated Chemo-Hyperthermia Kills Breast Cancer Stem Cells by Long-Term Reversal of Multidrug Resistance and Chemotherapy Resensitization

Cancer stem cells (CSCs) present a formidable challenge in cancer treatment due to their inherent resistance to chemotherapy, primarily driven by the overexpression of ABC transporters and multidrug resistance (MDR). Despite extensive research on pharmacological small-molecule inhibitors, effectively managing MDR and improving chemotherapeutic outcomes remain elusive. On the other hand, magnetic hyperthermia (MHT) holds great promise as a cancer therapeutic, but there is limited research on its potential to reverse MDR in breast CSCs and effectively eliminate CSCs through combined chemo-hyperthermia. To address these gaps, we developed tumor microenvironment-sensitive, drug-loaded poly(propylene sulfide) (PPS)-coated magnetic nanoparticles (PPS-MnFe). These nanoparticles were employed to investigate hyperthermia sensitivity and MDR reversion in breast CSCs, comparing their performance to that of small-molecule inhibitors. Additionally, we explored the efficacy of combined chemo-hyperthermia in killing CSCs. CSC-enriched breast cancer cells were subjected to low-dose MHT at 42 °C for 30 min and then treated with the chemical MDR inhibitor salinomycin (SAL). The effectiveness of each treatment in inhibiting MDR was assessed by measuring the efflux of the MDR substrate, rhodamine 123 (R123) dye. Notably, MHT induced a prolonged reversal of MDR activity compared with SAL treatment alone. After successfully inhibiting MDR, the breast CSCs were exposed to chemotherapy using paclitaxel to trigger synergistic cell death. The combination of MHT and chemotherapy demonstrated remarkable reductions in stemness properties, MDR reversal, and the effective eradication of breast CSCs in this innovative dual-modality approach.

Inducible caspase 9-mediated suicide gene therapy using AAV6 vectors in a murine model of breast cancer

Breast carcinoma has one of the highest incidence rates (11.7%), with significant clinical heterogeneity. Although conventional chemotherapy and surgical resection are the current standard of care, the resistance and recurrence, after these interventions, necessitate alternate therapeutic approaches. Cancer gene therapy for breast cancer with the suicide gene is an attractive option due to their directed delivery into the tumor. In this study, we have developed a novel treatment strategy against breast cancer with recombinant adeno-associated virus (AAV) serotype 6 vectors carrying a suicide gene, inducible Caspase 9 (iCasp9). Upon treatment with AAV6-iCasp9 vectors and the chemical inducer of dimerizer, AP20187, the viability of murine breast cancer cells (4T1) was significantly reduced to ∼40%-60% (mock control 100%). Following intratumoral delivery of AAV6-iCasp9 vectors in an orthotopic breast cancer mouse model, we observed a significant increase in iCasp9 transgene expression and a significant reduction in tumor growth rate. At the molecular level, immunohistochemical analysis demonstrated subsequent activation of the effector caspase 3 and cellular death. These data highlight the potential of AAV6-iCasp9-based suicide gene therapy for aggressive breast cancer in patients.

Single-Cell Proliferation Microfluidic Device for High Throughput Investigation of Replicative Potential and Drug Resistance of Cancer Cells

Introduction

Cell proliferation represents a major hallmark of cancer biology, and manifests itself in the assessment of tumor growth, drug resistance and metastasis. Tracking cell proliferation or cell fate at the single-cell level can reveal phenotypic heterogeneity. However, characterization of cell proliferation is typically done in bulk assays which does not inform on cells that can proliferate under given environmental perturbations. Thus, there is a need for single-cell approaches that allow longitudinal tracking of the fate of a large number of individual cells to reveal diverse phenotypes.

Methods

We fabricated a new microfluidic architecture for high efficiency capture of single tumor cells, with the capacity to monitor cell divisions across multiple daughter cells. This single-cell proliferation (SCP) device enabled the quantification of the fate of more than 1000 individual cancer cells longitudinally, allowing comprehensive profiling of the phenotypic heterogeneity that would be otherwise masked in standard cell proliferation assays. We characterized the efficiency of single cell capture and demonstrated the utility of the SCP device by exposing MCF-7 breast tumor cells to different doses of the chemotherapeutic agent doxorubicin.

Results

The single cell trapping efficiency of the SCP device was found to be ~ 85%. At the low doses of doxorubicin (0.01 µM, 0.001 µM, 0.0001 µM), we observed that 50-80% of the drug-treated cells had undergone proliferation, and less than 10% of the cells do not proliferate. Additionally, we demonstrated the potential of the SCP device in circulating tumor cell applications where minimizing target cell loss is critical. We showed selective capture of breast tumor cells from a binary mixture of cells (tumor cells and white blood cells) that was isolated from blood processing. We successfully characterized the proliferation statistics of these captured cells despite their extremely low counts in the original binary suspension.

Conclusions

The SCP device has significant potential for cancer research with the ability to quantify proliferation statistics of individual tumor cells, opening new avenues of investigation ranging from evaluating drug resistance of anti-cancer compounds to monitoring the replicative potential of patient-derived cells.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12195-023-00773-z.

A review of biological targets and therapeutic approaches in the management of triple-negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is a heterogeneous, aggressive phenotype of breast cancer with associated chemoresistance. The development of chemo- or radioresistance could be attributed to diverse tumor microenvironments, overexpression of membrane proteins (transporters), epigenetic changes, and alteration of the cell signaling pathways/genes associated with the development of cancer stem cells (CSCs).

AIM OF REVIEW

Due to the diverse and heterogeneous nature of TNBC, therapeutic response to the existing modalities offers limited scope and thus results in reccurance after therapy. To establish landmark therapeutic efficacy, a number of novel therapeutic modalities have been proposed. In addition, reversal of the resistance that developed during treatment may be altered by employing appropriate therapeutic modalities. This review aims to discuss the plethora of investigations carried out, which will help readers understand and make an appropriate choice of therapy directed toward complete elimination of TNBC.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This manuscript addresses the major contributory factors from the tumor microenvironment that are responsible for the development of chemoresistance and poor prognosis. The associated cellular events and molecular mechanism-based therapeutic interventions have been explained in detail. Inhibition of ABC transporters, cell signaling pathways associated with CSCs, and epigenetic modification offers promising results in this regard. TNBC progression, invasion, metastasis and recurrence can also be inhibited by blocking multiple cell signaling pathways, targeting specific receptors/epigenetic targets, disrupting bioenergetics and generating reactive oxygen species (ROS).

Breast cancer immunotherapy: a comprehensive review

Cancer remains a major health problem despite numerous new medical interventions that have been introduced in recent years. One of the major choices for cancer therapy is so-called adoptive cell therapy (ACT). ACT can be performed using both innate immune cells, including dendritic cells (DCs), natural killer (NK) cells, and γδ T cells and acquired immune T cells. It has become possible to utilize these cells in both their native and modified states in clinical studies. Because of considerable success in cancer treatment, ACT now plays a role in advanced therapy protocols. Genetic engineering of autologous and allogeneic immune cells (T lymphocytes, NK cells, macrophages, etc.) with chimeric antigen receptors (CAR) is a powerful new tool to target specific antigens on cancer cells. The Food and Drug Administration (FDA) in the US has approved certain CAR-T cells for hematologic malignancies and it is hoped that their use can be extended to incorporate a variety of cells, in particular NK cells. However, the ACT method has some limitations, such as the risk of rejection in allogeneic engrafts. Accordingly, numerous efforts are being made to eliminate or minimize this and other complications. In the present review, we have developed a guide to breast cancer (BC) therapy from conventional therapy, through to cell-based approaches, in particular novel technologies including CAR with emphasis on NK cells as a new and safer candidate in this field as well as the more recent aptamer technology, which can play a major role in BC immunotherapy.

Sulfobetaine methacrylate-coated reduced graphene oxide-IR780 hybrid nanosystems for effective cancer photothermal-photodynamic therapy

Nanomaterials with near infrared light absorption can mediate an antitumoral photothermal-photodynamic response that is weakly affected by cancer cells' resistance mechanisms. Such nanosystems are commonly prepared by loading photosensitizers into nanomaterials displaying photothermal capacity, followed by functionalization to achieve biological compatibility. However, the translation of these multifunctional nanomaterials has been limited by the fact that many of the photosensitizers are not responsive to near infrared light. Furthermore, the reliance on poly(ethylene glycol) for functionalizing the nanomaterials is also not ideal due to some immunogenicity reports. Herein, a novel photoeffective near infrared light-responsive nanosystem for cancer photothermal-photodynamic therapy was assembled. For such, dopamine-reduced graphene oxide was, for the first time, functionalized with sulfobetaine methacrylate-brushes, and then loaded with IR780 (IR780/SB/DOPA-rGO). This hybrid system revealed a nanometric size distribution, optimal surface charge and colloidal stability. The interaction of IR780/SB/DOPA-rGO with near infrared light prompted a temperature increase (photothermal effect) and production of singlet oxygen (photodynamic effect). In in vitro studies, the IR780/SB/DOPA-rGO per se did not elicit cytotoxicity (viability > 78 %). In contrast, the combination of IR780/SB/DOPA-rGO with near infrared light decreased breast cancer cells' viability to just 21 %, at a very low nanomaterial dose, highlighting its potential for cancer photothermal-photodynamic therapy.

ABCB1 Regulates Immune Genes in Breast Cancer

Background

Resistance to standard chemotherapy is a critical problem for breast cancer patients. The ATP-binding cassette (ABC) superfamily transporters actively pump out drugs and play an important role in chemoresistance. ABCB1 (ABC subfamily B, member 1, also named as multidrug resistance protein 1, MDR1) and suppressive myeloid-derived suppressor cells (MDSCs) potentially involve in chemoresistance of breast cancer. The relationship between ABCB1 and immune genes in breast cancer has not been widely studied.

Methods

Microarray and RNA sequencing data were obtained from The Cancer Genome Atlas Breast Invasive Carcinoma in Genomic Data Commons Data Portal and Gene Expression Omnibus database. A patient-derived xenograft (PDX) model of HER2+ breast cancer was established to investigate the association between ABCB1 and immune genes in breast cancer.

Results

Expression of ABCB1 increased in doxorubicin-selected MCF-7/ADR cells. High expression of ABCB1 mRNA is correlated with lymph-node metastasis and worse overall survival in patients with breast cancer. ABCB1 is positively correlated with IL6, CSF1, CSF3, and PTGS2. In the HER2+ stage IIA breast cancer PDX model, both doxorubicin and paclitaxel suppressed growth of P2 tumors. IL6, CSF1, CSF3, and PTGS2 expression were suppressed by paclitaxel but not doxorubicin. Intrasplenic MDSCs, including CD11b+Ly6G+ and CD11b+Ly6C+ cells, were more abundant than intratumor MDSCs in PDX-carrying nude mice. Clinically, the patient developed cancer recurrence after adjuvant chemotherapy with doxorubicin-based regimen and was well controlled after paclitaxel-trastuzumab combined therapy.

Conclusion

ABCB1 was a poor predictor of HER2+ LN- breast cancer. Regulation of immune genes by ABCB1 contributed to cancer recurrence and treatment effect. The PDX model was suitable for investigation the expression of target genes and expansion of immune cells.

Hyaluronic acid metabolism and chemotherapy resistance: recent advances and therapeutic potential

Hyaluronic acid (HA) is a major component of the extracellular matrix, providing essential mechanical scaffolding for cells and, at the same time, mediating essential biochemical signals required for tissue homeostasis. Many solid tumors are characterized by dysregulated HA metabolism, resulting in increased HA levels in cancer tissues. HA interacts with several cell surface receptors, such as cluster of differentiation 44 and receptor for hyaluronan-mediated motility, thus co-regulating important signaling pathways in cancer development and progression. In this review, we describe the enzymes controlling HA metabolism and its intracellular effectors emphasizing their impact on cancer chemotherapy resistance. We will also explore the current and future prospects of HA-based therapy, highlighting the opportunities and challenges in the field.

Breast Cancer Chemoresistance: Insights into the Regulatory Role of lncRNA

Long noncoding RNAs (lncRNAs) are a subclass of noncoding RNAs composed of more than 200 nucleotides without the ability to encode functional proteins. Given their involvement in critical cellular processes such as gene expression regulation, transcription, and translation, lncRNAs play a significant role in organism homeostasis. Breast cancer (BC) is the second most common cancer worldwide and evidence has shown a relationship between aberrant lncRNA expression and BC development. One of the main obstacles in BC control is multidrug chemoresistance, which is associated with the deregulation of multiple mechanisms such as efflux transporter activity, mitochondrial metabolism reprogramming, and epigenetic regulation as well as apoptosis and autophagy. Studies have shown the involvement of a large number of lncRNAs in the regulation of such pathways. However, the underlying mechanism is not clearly elucidated. In this review, we present the principal mechanisms associated with BC chemoresistance that can be directly or indirectly regulated by lncRNA, highlighting the importance of lncRNA in controlling BC chemoresistance. Understanding these mechanisms in deep detail may interest the clinical outcome of BC patients and could be used as therapeutic targets to overcome BC therapy resistance.

4-(3-Alkyl-2-oxoimidazolidin-1-yl)-N-phenylbenzenesulfonamide salts: Novel hydrosoluble prodrugs of antimitotics selectively bioactivated by the cytochrome P450 1A1 in breast cancer cells

4-(3-Alkyl-2-oxoimidazolidin-1-yl)-N-phenylbenzenesulfonamides (PAIB-SAs) are members of a new family of prodrugs bioactivated by cytochrome P450 1A1 (CYP1A1) in breast cancer cells into their potent 4-(2-oxoimidazolidin-1-yl)-N-phenylbenzenesulfonamide metabolites (PIB-SAs). One of the predominant problems for the galenic formulation and administration of PAIB-SAs in animal studies is their poor hydrosolubility. To circumvent that difficulty, we report the design, the synthesis, the chemical characterization, the evaluation of the aqueous solubility, the antiproliferative activity and the mechanism of action of 18 new Na+, K+ and Li+ salts of PAIB-SAs. Our results evidenced that the latter exhibited highly selective antiproliferative activity toward MCF7 and MDA-MB-468 breast cancer cells expressing endogenously CYP1A1 compared to insensitive MDA-MB-231 and HaCaT cells. Moreover, PAIB-SA salts 1-18 are significantly more hydrosoluble (3.9-9.4 mg/mL) than their neutral counterparts (< 0.0001 mg/mL). In addition, the most potent PAIB-SA salts 1-3 and 10-12 arrested the cell cycle progression in the G2/M phase and disrupted the cytoskeleton's dynamic assembly. Finally, PAIB-SA salts are N-dealkylated by CYP1A1 into their corresponding PIB-SA metabolites, which are potent antimitotics. In summary, our results show that our water-soluble PAIB-SA salts, notably the sodium salts, still exhibit potent antiproliferative efficacy and remain prone to CYP1A1 bioactivation. In addition, these PAIB-SA salts will allow the development of galenic formulations suitable for further biopharmaceutical and pharmacodynamic studies.

Design-of-Experiment-Assisted Fabrication of Biodegradable Polymeric Nanoparticles: In Vitro Characterization, Biological Activity, and In Vivo Assessment

Berberine (BER) is an alkaloid obtained from berberis plant having broad biological activities including anticancer. BER-encapsulated alginate (ALG)/chitosan (CHS) nanoparticles (BER-ALG/CHS-NPs) were developed for long-acting improved treatment in breast cancer. The surface of the NPs was activated by a conjugation reaction, and thereafter, the BER-ALG/CHS-NP surface was grafted with folic acid (BER-ALG/CHS-NPs-F) for specific targeting in breast cancer. BER-ALG/CHS-NPs-F was optimized by applying the Box-Behnken design using Expert design software. Moreover, formulations are extensively evaluated in vitro for biopharmaceutical performances and tested for cell viability, cellular uptake, and antioxidant activity. The comparative pharmacokinetic study of formulation and free BER was carried out in animals for estimation of bioavailability. The particle size recorded for the diluted sample using a Malvern Zetasizer was 240 ± 5.6 nm. The ζ-potential and the predicted % entrapment efficiency versus (vs) observed were +18 mV and 83.25 ± 2.3% vs 85 ± 3.5%. The high % drug release from the NPs was recorded. The analytical studies executed using infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction expressed safe combinations of the components in the formulation and physical state of the drug revealed to be amorphous in the formulation. Cytotoxicity testing demonstrated that the formulation effectively lowered the cell viability and IC50 of the tested cell line in comparison to a raw drug. The cellular uptake of BER-ALG/CHS-NPs-F was 5.5-fold higher than that of BER-suspension. The antioxidant capacities of BER-ALG/CHS-NPs-F vs BER-suspension by the DPPH assay were measured to be 62.3 ± 2.5% vs 30 ± 6%, indicating good radical scavenging power of folate-conjugated NPs. The developed formulation showed a 4.4-fold improved oral bioavailability compared to BER-suspension. The hemolytic assay intimated <2% destruction of erythrocytes by the developed formulation. The observed experimental characterization results such as cytotoxicity, cellular uptake, antioxidant activity, and improved absorption suggested the effectiveness of BER-ALG/CHS-NPs-F toward breast cancer.

A hybrid breast cancer/mesenchymal stem cell population enhances chemoresistance and metastasis

Patients with triple-negative breast cancer remain at risk for metastatic disease despite treatment. The acquisition of chemoresistance is a major cause of tumor relapse and death, but the mechanisms are far from understood. We have demonstrated that breast cancer cells (BCCs) can engulf mesenchymal stem/stromal cells (MSCs), leading to enhanced dissemination. Here, we show that clinical samples of primary invasive carcinoma and chemoresistant breast cancer metastasis contain a unique hybrid cancer cell population coexpressing pancytokeratin and the MSC marker fibroblast activation protein-α. We show that hybrid cells form in primary tumors and that they promote breast cancer metastasis and chemoresistance. Using single-cell microfluidics and in vivo models, we found that there are polyploid senescent cells within the hybrid cell population that contribute to metastatic dissemination. Our data reveal that Wnt Family Member 5A (WNT5A) plays a crucial role in supporting the chemoresistance properties of hybrid cells. Furthermore, we identified that WNT5A mediates hybrid cell formation through a phagocytosis-like mechanism that requires BCC-derived IL-6 and MSC-derived C-C Motif Chemokine Ligand 2. These findings reveal hybrid cell formation as a mechanism of chemoresistance and suggest that interrupting this mechanism may be a strategy in overcoming breast cancer drug resistance.

Selective HDAC3 Inhibitors with Potent In Vivo Antitumor Efficacy against Triple-Negative Breast Cancer

HDAC3 modulation shows promise for breast cancer, including triple-negative cases. Novel pyrazino-hydrazide-based HDAC3 inhibitors were designed and synthesized. Lead compound 4i exhibited potent HDAC3 inhibition (IC50 = 14 nM) with at least 121-fold selectivity. It demonstrated strong cytotoxicity against triple-negative breast cancer cells (IC50: 0.55 μM for 4T1, 0.74 μM for MDA-MB-231) with least normal cell toxicity. Metabolically stable 4i displayed a superior pharmacokinetic profile. A dose-dependent therapeutic efficacy of 4i was observed in a tumor-bearing mouse model. The biomarker analysis with tumor tissues displayed enhanced acetylation on Ac-H3K9, Ac-H3K27, and Ac-H4K12 compared to Ac-tubulin and Ac-SMC3 indicating HDAC3 selectivity of 4i in vivo. The immunoblotting study with tumor tissue showed upregulation of apoptotic proteins caspase-3, caspase-7, and cytochrome c and the downregulation of proliferation markers Bcl-2, CD44, EGFR, and Ki-67. Compound 4i represents a promising candidate for targeted breast cancer therapy, particularly for cases with triple-negative breast cancer.

Moringa oleifera: A Review on the Antiproliferative Potential in Breast Cancer Cells

The global burden of female breast cancer and associated deaths has become a major concern. Many chemotherapeutic agents, such as doxorubicin, have been shown to have adverse side effects. The development of multi-drug resistance is a common occurrence, contributing to chemotherapeutic failure. The resistance of breast cancer cells to drug treatment leads to a decline in the treatment efficacy and an increase in cancer recurrence. Therefore, action is required to produce alternative drug therapies, such as herbal drugs. Herbal drugs have been proven to be beneficial in treating illnesses, including cancer. This review aims to highlight the antiproliferative potential of Moringa oleifera (MO), a medicinal tree native to India and indigenous to Africa, in breast cancer cells. Although MO is not yet considered a commercial chemopreventive drug, previous studies have indicated that it could become a chemotherapeutic agent. The possible antiproliferative potential of MO aqueous leaf extract has been previously proven through its antioxidant potential as well as its ability to induce apoptosis. This review will provide an increased understanding of the effect that MO aqueous leaf extract could potentially have against breast cancer.

Predictive miRNAs Patterns in Blood of Breast Cancer Patients Demonstrating Resistance Towards Neoadjuvant Chemotherapy

Objective

The effect of chemotherapy in patients with breast cancer (BC) is uncertain. This study attempted to analyze serum microRNAs (miRNAs) in NAC resistant and sensitive BC patients and develop a miRNA-based nomogram model. To further help clinicians make treatment decisions for hormone receptor-positive patients.

Methods

A total of 110 BC patients with NAC were recruited and assigned in sensitive and resistant group, and 4 sensitive patients and 3 resistant patients were subjected to high-throughput sequencing. The functions of their target genes were analyzed by GO and KEGG. Five BC-related reported miRNAs were selected for expression pattern measurement by RT-qPCR and multivariate logistic analysis. The nomogram model was developed using R 4.0.1, and its predictive efficacy, consistency and clinical application value in development and validation groups were evaluated using ROC, calibration and decision curves.

Results

There were 44 differentially-expressed miRNAs in resistant BC patients. miR-3646, miR-4741, miR-6730-3p, miR-6831-5p and miR-8485 were candidate for resistance diagnosis in BC. Logistic multiple regression analysis showed that miR-4741 (or = 0.30, 95% CI = 0.08-0.63, P = 0.02) and miR-6831-5p (or = 0.48, 95% CI = 0.24-0.78, P = 0.01) were protective factors of BC resistance. The ROC curves showed a sensitivity of 0.884 and 0.750 for miR-4741 and miR-6831-5P as markers of resistance, suggesting that they can be used as independent risk factors for BC resistance. The other 3 miRNAs can be used as calibration factors to establish the risk prediction model of resistance in BC. In risk model, the prediction accuracy of resistance of BC is about 78%. 5-miRNA signature diagnostic models can help clinicians provide personalized treatment for NAC resistance BC patients to improve patient survival.

Conclusion

MiR-4741 and miR-6831-5p are independent risk factors for breast cancer resistance. This study constructed a nomogram model of NAC resistance in BC based on 5 differentially-expressed serum miRNAs.

Cancer chemoresistance and its mechanisms: Associated molecular factors and its regulatory role

Cancer therapy has advanced from tradition chemotherapy methods to targeted therapy, novel drug delivery mechanisms, combination therapies etc. Although several novel chemotherapy strategies have been introduced, chemoresistance still remains as one of the major barriers in cancer treatments. Chemoresistance can lead to relapse and hinder the development of improved clinical results for cancer patients, and this continues to be the major hurdle in cancer therapy. Anticancer drugs acquire chemoresistance through different mechanisms. Understanding these mechanisms is crucial to overcome and increase the efficiency of the cancer therapies that are employed. The potential molecular pathways behind chemoresistance include tumor heterogeneity, elevated drug efflux, multidrug resistance, interconnected signaling pathways, and other factors. To surpass this limitation, new clinical tactics are to be introduced. This review aims to compile the most recent information on the molecular pathways that regulate chemoresistance in cancers, which will aid in development of new therapeutic targets and strategies.

Shielding and nurturing: Fibronectin as a modulator of cancer drug resistance

Resistance to chemotherapy and targeted therapies constitute a common hallmark of most cancers and represent a dominant factor fostering tumor relapse and metastasis. Fibronectin, an abundant extracellular matrix glycoprotein, has long been proposed to play an important role in the pathobiology of cancer. Recent research has unraveled the role of Fibronectin in the onset of chemoresistance against a variety of antineoplastic drugs including DNA-damaging agents, hormone receptor antagonists, tyrosine kinase inhibitors, microtubule destabilizing agents, etc. The current review summarizes the role played by Fibronectin in mediating drug resistance against diverse anticancer drugs. We have also discussed how the aberrant expression of Fibronectin drives the oncogenic signaling pathways ultimately leading to drug resistance through the inhibition of apoptosis, promotion of cancer cell growth and proliferation.

Effects of Paclitaxel on Plasma Membrane Microviscosity and Lipid Composition in Cancer Cells

The cell membrane is an important regulator for the cytotoxicity of chemotherapeutic agents. However, the biochemical and biophysical effects that occur in the membrane under the action of chemotherapy drugs are not fully described. In the present study, changes in the microviscosity of membranes of living HeLa-Kyoto tumor cells were studied during chemotherapy with paclitaxel, a widely used antimicrotubule agent. To visualize the microviscosity of the membranes, fluorescence lifetime imaging microscopy (FLIM) with a BODIPY 2 fluorescent molecular rotor was used. The lipid profile of the membranes was assessed using time-of-flight secondary ion mass spectrometry ToF-SIMS. A significant, steady-state decrease in the microviscosity of membranes, both in cell monolayers and in tumor spheroids, was revealed after the treatment. Mass spectrometry showed an increase in the unsaturated fatty acid content in treated cell membranes, which may explain, at least partially, their low microviscosity. These results indicate the involvement of membrane microviscosity in the response of tumor cells to paclitaxel treatment.

Peptide-Based Vaccine against Breast Cancer: Recent Advances and Prospects

Breast cancer is considered the second-leading cancer after lung cancer and is the most prevalent cancer among women globally. Currently, cancer immunotherapy via vaccine has gained great attention due to specific and targeted immune cell activity that creates a potent immune response, thus providing long-lasting protection against the disease. Despite peptides being very susceptible to enzymatic degradation and poor immunogenicity, they can be easily customized with selected epitopes to induce a specific immune response and particulate with carriers to improve their delivery and thus overcome their weaknesses. With advances in nanotechnology, the peptide-based vaccine could incorporate other components, thereby modulating the immune system response against breast cancer. Considering that peptide-based vaccines seem to show remarkably promising outcomes against cancer, this review focuses on and provides a specific view of peptide-based vaccines used against breast cancer. Here, we discuss the benefits associated with a peptide-based vaccine, which can be a mainstay in the prevention and recurrence of breast cancer. Additionally, we also report the results of recent trials as well as plausible prospects for nanotechnology against breast cancer.

Antimicrobial peptide moricin induces ROS mediated caspase-dependent apoptosis in human triple-negative breast cancer via suppression of notch pathway

BACKGROUND

Breast cancer is the world's most prevalent cancer among women. Microorganisms have been the richest source of antibiotics as well as anticancer drugs. Moricin peptides have shown antibacterial properties; however, the anticancer potential and mechanistic insights into moricin peptide-induced cancer cell death have not yet been explored.

METHODS

An investigation through in silico analysis, analytical methods (Reverse Phase-High Performance Liquid Chromatography (RP-HPLC), mass spectroscopy (MS), circular dichroism (CD), and in vitro studies, has been carried out to delineate the mechanism(s) of moricin-induced cancer cell death. An in-silico analysis was performed to predict the anticancer potential of moricin in cancer cells using Anti CP and ACP servers based on a support vector machine (SVM). Molecular docking was performed to predict the binding interaction between moricin and peptide-related cancer signaling pathway(s) through the HawkDOCK web server. Further, in vitro anticancer activity of moricin was performed against MDA-MB-231 cells.

RESULTS

In silico observation revealed that moricin is a potential anticancer peptide, and protein-protein docking showed a strong binding interaction between moricin and signaling proteins. CD showed a predominant helical structure of moricin, and the MS result determined the observed molecular weight of moricin is 4544 Da. An in vitro study showed that moricin exposure to MDA-MB-231 cells caused dose dependent inhibition of cell viability with a high generation of reactive oxygen species (ROS). Molecular study revealed that moricin exposure caused downregulation in the expression of Notch-1, NF-ƙB and Bcl2 proteins while upregulating p53, Bax, caspase 3, and caspase 9, which results in caspase-dependent cell death in MDA-MB-231 cells.

CONCLUSIONS

In conclusion, this study reveals the anticancer potential and underlying mechanism of moricin peptide-induced cell death in triple negative cancer cells, which could be used in the development of an anticancer drug.

Pterostilbene-isothiocyanate reduces miR-21 level by impeding Dicer-mediated processing of pre-miR-21 in 5-fluorouracil and tamoxifen-resistant human breast cancer cell lines

Converging evidences identifies that microRNA-21 (miR-21) is responsible for drug resistance in breast cancer. This study aims to evaluate the miR-21-modulatory potential of a hybrid compound, pterostilbene-isothiocyanate (PTER-ITC), in tamoxifen-resistant MCF-7 (TR/MCF-7) and 5-fluorouracil-resistant MDA-MB 231 (5-FUR/MDA-MB 231) breast cancer cell lines, established by repeated exposure to gradually increasing the concentrations of tamoxifen and 5-fluorouracil, respectively. The outcome of this study shows that PTER-ITC effectively reduced the TR/MCF-7 (IC50: 37.21 µM) and 5-FUR/MDA-MB 231 (IC50: 47.00 µM) cell survival by inducing apoptosis, inhibiting cell migration, colony and spheroid formations in TR/MCF-7 cells, and invasiveness of 5-FUR/MDA-MB 231 cells. Most importantly, PTER-ITC significantly reduced the miR-21 expressions in these resistant cell lines. Moreover, the downstream tumor suppressor target gene of miR-21 such as PTEN, PDCD4, TIMP3, TPM1, and Fas L were upregulated after PTER-ITC treatment, as observed from transcriptional (RT-qPCR) and translational (immunoblotting) data. In silico and miR-immunoprecipitation (miR-IP) results showed reduced Dicer binding to pre-miR-21, after PTER-ITC treatment, indicating inhibition of miR-21 biogenesis. Collectively, the significance of this study is indicated by preliminary evidence for miR-21-modulatory effects of PTER-ITC that highlights the potential of this hybrid compound as an miR-21-targeting therapeutic agent.

The Interplay between Microbiota and Chemotherapy-Derived Metabolites in Breast Cancer

The most common cancer in women is breast cancer, which is also the second leading cause of death in this group. It is, however, important to note that some women will develop or will not develop breast cancer regardless of whether certain known risk factors are present. On the other hand, certain compounds are produced by bacteria in the gut, such as short-chain fatty acids, secondary bile acids, and other metabolites that may be linked to breast cancer development and mediate the chemotherapy response. Modeling the microbiota through dietary intervention and identifying metabolites directly associated with breast cancer and its complications may be useful to identify actionable targets and improve the effect of antiangiogenic therapies. Metabolomics is therefore a complementary approach to metagenomics for this purpose. As a result of the combination of both techniques, a better understanding of molecular biology and oncogenesis can be obtained. This article reviews recent literature about the influence of bacterial metabolites and chemotherapy metabolites in breast cancer patients, as well as the influence of diet.

OTUD1 chemosensitizes triple-negative breast cancer to doxorubicin by modulating P16 expression

Chemotherapy remains a critical component of triple-negative breast cancer (TNBC) treatment; however, patients often develop resistance to chemotherapeutic agents. Accumulating evidence indicates that deubiquitylases (DUBs) play pivotal roles in regulating cell proliferation, differentiation, apoptosis, and tumorigenesis. Deubiquitylase OTUD1 is considered a tumor suppressor in various cancers, yet its role in doxorubicin sensitivity in breast cancer patients remains inadequately understood. In this study, we investigated the expression levels and prognostic role of OTUD1 in breast cancer. Our findings demonstrated that OTUD1 was downregulated in TNBC, and lower OTUD1 expression levels were correlated with poor prognosis. We utilized the CCK-8 cell viability assay, flow cytometric analysis, and a TNBC mouse xenograft model to examine the influence of OTUD1 on doxorubicin (DOX) chemotherapy sensitivity in vitro and in vivo. Western blot and immunohistochemistry were employed to explore the correlation between OTUD1 and P16. Our results indicated that upregulation of OTUD1 expression inhibits TNBC cell proliferation and enhances its sensitivity to doxorubicin. Additionally, rescue experiments confirmed that the chemosensitizing effect of OTUD1 overexpression could be reversed by the inhibition of P16. Therefore, our findings reveal that OTUD1 sensitizes TNBC cells to DOX by upregulating P16 expression, suggesting a potential new diagnostic biomarker and therapeutic target for the future treatment of TNBC.

Aptamers against cancer drug resistance: Small fighters switching tactics in the face of defeat

Discovering novel cancer therapies has attracted extreme interest in the last decade. In this regard, multidrug resistance (MDR) to chemotherapies is the primary challenge in cancer treatment. Cancerous cells are growingly become resistant to existing chemotherapeutics by employing diverse mechanisms, highlighting the significance of discovering approaches to overcome MDR. One promising strategy is utilizing aptamers as unique tools to target elements or signalings incorporated in resistance mechanisms or develop active targeted drug delivery systems or chimeras enabling the precise delivery of novel agents to inhibit the conventionally undruggable resistance elements. Further, due to their advantages over their proteinaceous counterparts, particularly antibodies, including improved targeting action, enhanced thermal stability, easier production, and superior tumor penetration, aptamers are emerging and have frequently been considered for developing cancer therapeutics. Here, we highlighted significant chemoresistance pathways and thoroughly discussed using aptamers as prospective tools to surmount cancer MDR.

Aldose reductase and cancer metabolism: The master regulator in the limelight

It is strongly established that metabolic reprogramming mediates the initiation, progression, and metastasis of a variety of cancers. However, there is no common biomarker identified to link the dysregulated metabolism and cancer progression. Recent studies strongly advise the involvement of aldose reductase (AR) in cancer metabolism. AR-mediated glucose metabolism creates a Warburg-like effect and an acidic tumour microenvironment in cancer cells. Moreover, AR overexpression is associated with the impairment of mitochondria and the accumulation of free fatty acids in cancer cells. Further, AR-mediated reduction of lipid aldehydes and chemotherapeutics are involved in the activation of factors promoting proliferation and chemo-resistance. In this review, we have delineated the possible mechanisms by which AR modulates cellular metabolism for cancer proliferation and survival. An in-depth understanding of cancer metabolism and the role of AR might lead to the use of AR inhibitors as metabolic modulating agents for the therapy of cancer.

SCAMP3 promotes breast cancer progression through the c-MYC-β-Catenin-SQSTM1 growth and stemness axis

The cellular trafficking protein secretory-carrier-membrane-protein 3 (SCAMP3) has been previously shown to promote hepatocellular carcinoma, melanoma, glioma and pancreatic adenocarcinoma. Moreover, previous work has shown that SCAMP3 regulates the epidermal growth factor receptor (EGFR) in triple negative breast cancer (TNBC). However, the oncogenic role of SCAMP3 in different molecular subtypes of breast cancer (BRCA) remains largely unknown. In this study, the role of SCAMP3 in different molecular subtypes of BRCA was investigated using in silico, in vitro and in vivo approaches. In silico analysis of BRCA patient samples showed that SCAMP3 is highly overexpressed in different BRCA molecular subtypes, advanced disease grades and lymph node metastatic stages. Depletion of SCAMP3 inhibited BRCA cell growth, stemness, clonogenic potential and migration and promoted autophagy and cellular senescence. The expression of stemness markers CD44 and OCT4A was reduced in SCAMP3-silenced MDA-MB-231 cells. SCAMP3 overexpression promoted cell proliferation, clonogenicity, tumor spheroid formation and migration in vitro and tumor growth in vivo. SCAMP3 promoted epithelial-mesenchymal-transition (EMT) by regulating E-cadherin expression. SCAMP3 enhanced in vivo tumor growth in MDA-MB-231 tumor xenograft mouse model. Mechanistically, SCAMP3 depletion inhibited β-Catenin, c-MYC and SQSTM1 expression, while its overexpression increased the expression of the same oncogenic proteins. Increased SCAMP3 expression associated with increased chemoresistance in BRCA cells while its depletion associated with increased sensitivity to chemotherapy. BRCA patients with high SCAMP3 expression showed poor prognosis, decreased overall survival and relapse free survival relative to counterparts with reduced SCAMP3 expression. These findings suggest that SCAMP3 exerts a wide range of oncogenic effects in different molecular subtypes of BRCA by modulating the c-MYC-β-Catenin-SQSTM1 axis that targets tumor growth, metastasis, stemness and chemoresistance.

Exosomes derived from cancer-associated fibroblasts mediate response to cancer therapy

Cancer-associated fibroblasts (CAFs) are the prominent stromal cell population in the tumor microenvironment (TME), which play an indispensable role in cancer progression and response to therapy. CAFs provide communication between tumor cells and surrounding cells by secreting soluble biomolecules and extracellular vesicles (EVs). Exosomes are small membrane-bound EVs that contain various cargos, including growth factors, non-coding RNAs (ncRNAs), cytokines, and chemokines. These biomolecules can be transferred between cells within the TME and alter the behavior of recipient cells. Some studies have shown that exosomes secreted by CAFs contribute to resistance to chemotherapy and radiotherapy. This review focuses on CAF-derived exosomes in different types of tumors, with emphasis on resistance to chemotherapy and radiotherapy.

Synthesis and the In Vitro Evaluation of Antitumor Activity of Novel Thiobenzanilides

Cancer is a generic term for a large group of diseases that are the second-leading cause of death worldwide, accounting for nearly 10 million deaths in 2020. Melanoma is a highly aggressive skin tumor with an increasing incidence and poor prognosis in the metastatic stage. Breast cancer still stands as one of the major cancer-associated deaths among women, and diagnosed cases are increasing year after year worldwide. Despite the recent therapeutic advances for this type of cancer, novel drugs and treatment strategies are still urgently needed. In this paper, the synthesis of 18 thiobenzanilide derivatives (17 of them new) is described, and their cytotoxic potential against melanoma cells (A375) and hormone-dependent breast cancer (MCF-7) cells is evaluated using the MTT assay. In the A375 cell line, most of the tested thiobenzanilides derivatives showed EC₅₀ values in the order of μM. Compound 17 was the most promising, with an EC₅₀ (24 h) of 11.8 μM. Compounds 8 and 9 are also interesting compounds that deserve to be further improved. The MCF-7 cell line, on the other hand, was seen to be less susceptible to these thiobenzanilides indicating that these compounds show different selectivity towards skin and breast cancer cells. Compound 15 showed the highest cytotoxic potential for MCF-7 cells, with an EC₅₀ (24 h) of 43 μM, a value within the range of the EC₅₀ value determined for tamoxifen (30.0 μM). ADME predictions confirm the potential of the best compounds. Overall, this work discloses a new set of thiobenzanilides that are worth being considered as new scaffolds for the further development of anticancer agents.

Box-Behnken assisted development and validation of high-performance liquid chromatography method for the simultaneous determination of doxorubicin and vorinostat in polymeric nanoparticles

While histone deacetylase inhibitors, such as vorinostat, demonstrate a significant effect against hematological cancers, their application for solid tumor treatment is limited. However, there is strong evidence that combinatorial administration of vorinostat and genotoxic agents (e.g., doxorubicin) enhances the antitumoral action of both drugs against tumors. We developed a high-performance liquid chromatography method for the simultaneous determination of doxorubicin and vorinostat in polymeric nanoparticles designed to provide the parenteral administration of both drugs and increase their safety profile. We performed separation on Nucleodur C-18 Gravity column with a mixture of 10 mM potassium dihydrogen phosphate buffer pH 3.9:ACN (90:10 v/v) as mobile phase at 240 nm. The method was linear within the concentration range of 4.2-52.0 μg/ml for both drugs with limits of detection and quantification of 3.5 and 10.7 μg/ml for doxorubicin and 2.5 and 7.7 μg/ml for vorinostat, respectively. The method was precise and accurate over the concentration range of analysis. Drug loading was 5.4% for doxorubicin and 0.8% for vorinostat. Degradation of doxorubicin after irradiation was less than 5%, while the amount of vorinostat decreased at 88% under the same conditions. Thus, the validated method could be adopted for routine simultaneous analysis of doxorubicin and vorinostat in polymeric nanoparticles.

Recent Advances in Mesoporous Silica Nanoparticle-Mediated Drug Delivery for Breast Cancer Treatment

Breast cancer (BC) currently occupies the second rank in cancer-related global female deaths. Although consistent awareness and improved diagnosis have reduced mortality in recent years, late diagnosis and resistant response still limit the therapeutic efficacy of chemotherapeutic drugs (CDs), leading to relapse with consequent invasion and metastasis. Treatment with CDs is indeed well-versed but it is badly curtailed with accompanying side effects and inadequacies of site-specific drug delivery. As a result, drug carriers ensuring stealth delivery and sustained drug release with improved pharmacokinetics and biodistribution are urgently needed. Core-shell mesoporous silica nanoparticles (MSNPs) have recently been a cornerstone in this context, attributed to their high surface area, low density, robust functionalization, high drug loading capacity, size-shape-controlled functioning, and homogeneous shell architecture, enabling stealth drug delivery. Recent interest in using MSNPs as drug delivery vehicles has been due to their functionalization and size-shape-driven versatilities. With such insights, this article focuses on the preparation methods and drug delivery mechanisms of MSNPs, before discussing their emerging utility in BC treatment. The information compiled herein could consolidate the database for using inorganic nanoparticles (NPs) as BC drug delivery vehicles in terms of design, application and resolving post-therapy complications.