Recent advances in HER2-targeted delivery for cancer therapy

Current status and future challenges of CAR-T cell therapy for osteosarcoma

Osteosarcoma, the most common bone malignancy in children and adolescents, poses considerable challenges in terms of prognosis, especially for patients with metastatic or recurrent disease. While surgical intervention and adjuvant chemotherapy have improved survival rates, limitations such as impractical tumor removal or chemotherapy resistance hinder the treatment outcomes. Chimeric antigen receptor (CAR)-T cell therapy, an innovative immunotherapy approach that involves targeting tumor antigens and releasing immune factors, has shown significant advancements in the treatment of hematological malignancies. However, its application in solid tumors, including osteosarcoma, is constrained by factors such as low antigen specificity, limited persistence, and the complex tumor microenvironment. Research on osteosarcoma is ongoing, and some targets have shown promising results in pre-clinical studies. This review summarizes the current status of research on CAR-T cell therapy for osteosarcoma by compiling recent literature. It also proposes future research directions to enhance the treatment of osteosarcoma.

Development of High-Loading Trastuzumab PLGA Nanoparticles: A Powerful Tool Against HER2 Positive Breast Cancer Cells

Background

Trastuzumab, a therapeutic monoclonal antibody directed against HER2, is routinely used to treat HER2-positive breast cancer with a good response rate. However, concerns have arisen in the clinical practice due to adverse side effects. One way to overcome these limitations is to encapsulate trastuzumab in nanoparticles to improve cytotoxic activity, increase intracellular drug concentrations, escape the immune system and avoid systemic degradation of the drug in vivo.

Methods

A double emulsion method was used to encapsulate trastuzumab into poly(lactic-co-glycolic) nanoparticles, effective for their biocompatibility and biodegradability. These nanocarriers, hereafter referred to as TZPs, were characterised in terms of size, homogeneity, zeta potential and tested for their stability and drug release kinetics. Finally, the TZPs cytotoxicity was assessed in vitro on the HER2 positive SKBR3 breast cancer cell line and compared to free trastuzumab.

Results

The TZPs were stable, homogeneous in size, with a reduced zeta potential. They showed higher encapsulation efficiency and drug loading, a prolonged trastuzumab release kinetics that retained its physicochemical properties and functionality. TZPs showed a stronger cytotoxicity and increased apoptosis than similar doses of free trastuzumab in the cell line analysed. Confocal microscopy and flow cytometry assessed TZPs and trastuzumab cellular uptake while Western blot evaluated downstream signalling, overall HER2 content and shedding.

Conclusion

TZPs exert more robust effects than free trastuzumab via a dual mode of action: TZPs are taken up by cells through an endocytosis mechanism and release the drug intracellularly for longer time. Additionally, the TZPs that remain in the extracellular space release trastuzumab which binds to the cognate receptor and impairs downstream signalling. This is the sole modality used by free trastuzumab. Remarkably, half dose of TZPs is as efficacious as the highest dose of free drug supporting their possible use for drug delivery in vivo.

The PTX3/TLR4 autocrine loop as a novel therapeutic target in triple negative breast cancer

BACKGROUND

The pattern recognition receptor long pentraxin-3 (PTX3) plays conflicting roles in cancer by acting as an oncosuppressor or as a pro-tumor mediator depending on tumor context. Triple negative breast cancer (TNBC) represents the most aggressive histotype of breast cancer, characterized by the lack of efficacious therapeutic targets/approaches and poor prognosis. Thus, the characterization of new molecular pathways and/or alternative druggable targets is of great interest in TNBC.

METHODS

The expression of PTX3 in BC tumor samples and in BC cell lines has been analyzed using the Gene Expression-Based Outcome for Breast Cancer Online (GOBO), qPCR, Western blot and ELISA assay. The contribution of tumor and stromal cells to PTX3 production in TNBC was assessed by analyzing single cell RNA sequencing data and RNAscope performed on TNBC tumor samples. In order to investigate the effects of PTX3 in TNBC, different cell lines were engineered to knock-down (MDA-MB-231 and BT549 cells) or overexpress (MDA-MB-468 and E0771 cells) PTX3. Finally, using these engineered cells, in vitro (including gene expression profiling and gene set enrichment analyses) and in vivo (orthotopic tumor models in immune-compromised and immune competent mice) analyses were performed to assess the role and the molecular mechanism(s) exerted by PTX3 in TNBC.

RESULTS

In silico and experimental data indicate that PTX3 is mainly produced by tumor cells in TNBC and that its expression levels correlate with tumor stage. Accordingly, gene expression and in vitro results demonstrate that PTX3 overexpression confers a high aggressive/proliferative phenotype and fosters stem-like features in TNBC cells. Also, PTX3 expression induces a more tumorigenic potential when TNBC cells are grafted orthotopically in vivo. Conversely, PTX3 downregulation results in a less aggressive behavior of TNBC cells. Mechanistically, our data reveal that PTX3 drives the activation of the pro-tumorigenic Toll-like receptor 4 (TLR4) signaling pathway in TNBC, demonstrating for the first time that the PTX3/TLR4 autocrine stimulation loop contributes to TNBC aggressiveness and that TLR4 inhibition significantly impacts the growth of PTX3-producing TNBC cells.

CONCLUSION

Altogether, these data shed light on the role of tumor-produced PTX3 in TNBC and uncover the importance of the PTX3/TLR4 axis for therapeutic and prognostic exploitation in TNBC.

Nanomedicine in cancer therapy

Cancer remains a highly lethal disease in the world. Currently, either conventional cancer therapies or modern immunotherapies are non-tumor-targeted therapeutic approaches that cannot accurately distinguish malignant cells from healthy ones, giving rise to multiple undesired side effects. Recent advances in nanotechnology, accompanied by our growing understanding of cancer biology and nano-bio interactions, have led to the development of a series of nanocarriers, which aim to improve the therapeutic efficacy while reducing off-target toxicity of the encapsulated anticancer agents through tumor tissue-, cell-, or organelle-specific targeting. However, the vast majority of nanocarriers do not possess hierarchical targeting capability, and their therapeutic indices are often compromised by either poor tumor accumulation, inefficient cellular internalization, or inaccurate subcellular localization. This Review outlines current and prospective strategies in the design of tumor tissue-, cell-, and organelle-targeted cancer nanomedicines, and highlights the latest progress in hierarchical targeting technologies that can dynamically integrate these three different stages of static tumor targeting to maximize therapeutic outcomes. Finally, we briefly discuss the current challenges and future opportunities for the clinical translation of cancer nanomedicines.

Efficient Convolution Network to Assist Breast Cancer Diagnosis and Target Therapy

Breast cancer is the leading cause of cancer-related deaths among women worldwide, and early detection and treatment has been shown to significantly reduce fatality rates from severe illness. Moreover, determination of the human epidermal growth factor receptor-2 (HER2) gene amplification by Fluorescence in situ hybridization (FISH) and Dual in situ hybridization (DISH) is critical for the selection of appropriate breast cancer patients for HER2-targeted therapy. However, visual examination of microscopy is time-consuming, subjective and poorly reproducible due to high inter-observer variability among pathologists and cytopathologists. The lack of consistency in identifying carcinoma-like nuclei has led to divergences in the calculation of sensitivity and specificity. This manuscript introduces a highly efficient deep learning method with low computing cost. The experimental results demonstrate that the proposed framework achieves high precision and recall on three essential clinical applications, including breast cancer diagnosis and human epidermal receptor factor 2 (HER2) amplification detection on FISH and DISH slides for HER2 target therapy. Furthermore, the proposed method outperforms the majority of the benchmark methods in terms of IoU by a significant margin (p<0.001) on three essential clinical applications. Importantly, run time analysis shows that the proposed method obtains excellent segmentation results with notably reduced time for Artificial intelligence (AI) training (16.93%), AI inference (17.25%) and memory usage (18.52%), making the proposed framework feasible for practical clinical usage.

Molecularly imprinted polymers (MIPs): emerging biomaterials for cancer theragnostic applications

Cancer is a disease caused by abnormal cell growth that spreads through other parts of the body and threatens life by destroying healthy tissues. Therefore, numerous techniques have been employed not only to diagnose and monitor the progress of cancer in a precise manner but also to develop appropriate therapeutic agents with enhanced efficacy and safety profiles. In this regard, molecularly imprinted polymers (MIPs), synthetic receptors that recognize targeted molecules with high affinity and selectivity, have been intensively investigated as one of the most attractive biomaterials for theragnostic approaches. This review describes diverse synthesis strategies to provide the rationale behind these synthetic antibodies and provides a selective overview of the recent progress in the in vitro and in vivo targeting of cancer biomarkers for diagnosis and therapeutic applications. Taken together, the topics discussed in this review provide concise guidelines for the development of novel MIP-based systems to diagnose cancer more precisely and promote successful treatment. Molecularly imprinted polymers (MIPs), synthetic receptors that recognize targeted molecules with high affinity and selectivity, have been intensively investigated as one of the most attractive biomaterials for cancer theragnostic approaches. This review describes diverse synthesis strategies to provide the rationale behind these synthetic antibodies and provides a selective overview of the recent progress in the in vitro and in vivo targeting of cancer biomarkers for diagnosis and therapeutic applications. The topics discussed in this review aim to provide concise guidelines for the development of novel MIP-based systems to diagnose cancer more precisely and promote successful treatment.

Recent advances in cold atmospheric plasma (CAP) for breast cancer therapy

The serious problems of conventional breast cancer therapy strategies such as drug resistance, severe side effects, and lack of selectivity prompted the development of various cold atmospheric plasma (CAP) devices. Due to its advanced technology, CAP can produce a unique environment rich in reactive oxygen and nitrogen species (RONS), photons, charged ions, and an electric field, making it a promising revolutionary platform for cancer therapy. Despite substantial technological successes, CAP-based therapeutic systems are encounter with distinct limitations, including low control of the generated RONS, poor knowledge about its anticancer mechanisms, and challenges concerning designing, manufacturing, clinical translation, and commercialization, which must be resolved. The latest developments in CAP-based therapeutic systems for breast cancer treatment are discussed in this review. More significantly, the integration of CAP-based medicine approaches with other breast cancer therapies, including chemo- and nanotherapy is thoroughly addressed.

ICG-Dimeric Her2-Specific Affibody Conjugates for Tumor Imaging and Photothermal Therapy for Her2-Positive Tumors

Human epidermal growth factor receptor 2 (Her2) is abundantly expressed in various solid tumors. The Her2-specific Affibody (Z_Her2:2891) has been clinically tested in patients with Her2-positive breast cancer and is regarded as an ideal drug carrier for tumor diagnosis and targeted treatment. Indocyanine green (ICG) can be used as a photosensitizer for photothermal therapy (PTT), in addition to fluorescent dyes for tumor imaging. In this study, a dimeric Her2-specific Affibody (Z_Her2) based on Z_Her2:2891 was prepared using the E. coli expression system and then coupled to ICG through an N-hydroxysuccinimide (NHS) ester reactive group to construct a novel bifunctional protein drug (named ICG-Z_Her2) for tumor diagnosis and PTT. In vitro, ICG-Z_Her2-mediated PTT selectively and efficiently killed Her2-positive BT-474 and SKOV-3 tumor cells rather than Her2-negative HeLa tumor cells. In vivo, ICG-Z_Her2 specifically accumulated in Her2-positive SKOV-3 tumor grafts rather than Her2-negative HeLa tumor grafts; high-contrast tumor optical images were obtained. However, Her2-negative HeLa tumor grafts were not detected. More importantly, ICG-Z_Her2-mediated PTT exhibited a significantly enhanced antitumor effect in mice bearing SKOV-3 tumor grafts owing to the good photothermal properties of ICG-Z_Her2. Of note, ICG-Z_Her2 did not exhibit acute toxicity in mice during short-term treatment. Overall, our findings indicate that ICG-Z_Her2 is a promising bifunctional drug for Her2-positive tumor diagnosis and PTT.

GSK-J1-loaded, hyaluronic acid-decorated metal-organic frameworks for the treatment of ovarian cancer

Despite intensive research, ovarian cancer has the highest mortality rates among gynecological malignancies, partly because of its rapid acquisition of chemoresistance to platinum therapy. Hence, strategies are needed to effectively treat carboplatin-resistant ovarian cancer. In this study, we designed and prepared hyaluronic acid-decorated metal-organic frameworks for the targeted delivery of GSK-J1, a JMJD3 demethylase inhibitor (HA@MOF@GSK-J1) for the synergistic treatment of carboplatin-resistant ovarian cancer. HA@MOF@GSK-J1 showed outstanding effectiveness in the inhibition of ovarian cancer in vitro. Furthermore, HA@MOF@GSK-J1 demonstrated higher induction of apoptosis, reduced cell motility, and diminished cell spheroids by attenuating HER2 activity through the effectual activation of H3K27 methylation in its promoter area. Finally, our in vivo results confirmed that HA@MOF@GSK-J1 had better treatment efficacy for carboplatin-resistant ovarian tumor xenografts. Our results highlight the potential of HA@MOF@GSK-J1 as an effective strategy to improve the treatment of carboplatin-resistant ovarian cancer.

Nanodelivery of cGAS-STING activators for tumor immunotherapy

Activation of the cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS)-stimulator of interferon genes (STING) pathway has great potential to promote antitumor immunity. Development of activators for the cGAS-STING pathway (cGAS-STING activators) has profoundly revolutionized tumor immunotherapy. However, successful clinical application of cGAS-STING activators is contingent on having appropriate systems to achieve safe, effective, and specific delivery. There is an increasing emphasis on the design and application of nano drug delivery systems (NDDS) that can facilitate the delivery potential of cGAS-STING activators. In this review, we discuss barriers for translational development of cGAS-STING activators (DNA damaging drugs and STING agonists) and recent advances of NDDS for these agents in tumor immunotherapy.

Chimeric Antigen Receptor (CAR)-T Cell Immunotherapy Against Thoracic Malignancies: Challenges and Opportunities

Different from surgery, chemical therapy, radio-therapy and target therapy, Chimeric antigen receptor-modified T (CAR-T) cells, a novel adoptive immunotherapy strategy, have been used successfully against both hematological tumors and solid tumors. Although several problems have reduced engineered CAR-T cell therapeutic outcomes in clinical trials for the treatment of thoracic malignancies, including the lack of specific antigens, an immunosuppressive tumor microenvironment, a low level of CAR-T cell infiltration into tumor tissues, off-target toxicity, and other safety issues, CAR-T cell treatment is still full of bright future. In this review, we outline the basic structure and characteristics of CAR-T cells among different period, summarize the common tumor-associated antigens in clinical trials of CAR-T cell therapy for thoracic malignancies, and point out the current challenges and new strategies, aiming to provide new ideas and approaches for preclinical experiments and clinical trials of CAR-T cell therapy for thoracic malignancies.

Inhibition of PFKFB3 in HER2-positive gastric cancer improves sensitivity to trastuzumab by inducing tumour vessel normalisation

BACKGROUND

Multiple mechanisms have been proposed that lead to reduced effectiveness of trastuzumab in HER2-positive gastric cancer (GC), yet resistance to trastuzumab remains a challenge in clinics.

METHODS

We established trastuzumab-resistant cells and patient-derived xenografts models to measure metabolic levels and vascular density and shape. The HER2-positive GC patient samples were used to determine clinical significance. We also measured protein expression and phosphorylation modifications to determine those alterations related to resistance. In vivo studies combining inhibitor of PFKFB3 with trastuzumab corroborated the in vitro findings.

RESULTS

The 6-phosphofructo-2-kinase (PFKFB3)-mediated trastuzumab resistance pathways in HER2-positive GC by activating the glycolytic pathway. We also found vessels are chaotic and destabilised in the tumour during the trastuzumab resistance process. Inhibition of PFKFB3 significantly diminished tumour proliferation and promoted vessel normalisation in the patient-derived xenograft model. Mechanistically, PFKFB3 promoted the secretion of CXCL8 into the tumour microenvironment, and phosphorylated Ser1151 of ERBB2, enhancing the transcription of CXCL8 by activating the PI3K/AKT/NFκB p65 pathway.

CONCLUSIONS

Our current findings discover that PFKFB3 inhibitors might be effective tools to overcome adjuvant therapy resistance in HER2-positive GC and reshaping the microenvironment by normalising tumour vessels is a novel strategy to overcome trastuzumab resistance.

Chemical Conjugation in Drug Delivery Systems

Cancer is one of the diseases with the highest mortality rate. Treatments to mitigate cancer are usually so intense and invasive that they weaken the patient to cure as dangerous as the own disease. From some time ago until today, to reduce resistance generated by the constant administration of the drug and improve its pharmacokinetics, scientists have been developing drug delivery system (DDS) technology. DDS platforms aim to maximize the drugs’ effectiveness by directing them to reach the affected area by the disease and, therefore, reduce the potential side effects. Erythrocytes, antibodies, and nanoparticles have been used as carriers. Eleven antibody–drug conjugates (ADCs) involving covalent linkage has been commercialized as a promising cancer treatment in the last years. This review describes the general features and applications of DDS focused on the covalent conjugation system that binds the antibody carrier to the cytotoxic drug.

Improvement of cytotoxicity and necrosis activity of ganoderic acid a through the development of PMBN-A.Her2-GA as a targeted nano system

The targeting nano carriers have been promptly proposed to overcome the current obstacles in conventional chemotherapy approaches for cancer. Currently, PMBN (poly[MPC-co-(BMA)-co-(MEONP)]), is considered as a promising amphiphilic polymer that could be easily targeted and conjugated to hydrophobic substances with low bioavailability. To target breast cancer cells overexpressing human epidermal receptor 2 (HER2) receptors, anti-HER2 monoclonal antibody (A.Her2) was conjugated to PMBN and afterward loaded with ganoderic acid A (GA-A) as an anti-cancer metabolite. The efficacy of conjugation and loading was reasonably favourable. The rod shape of the polymer with a size of approximately 160 ± 30 nm was confirmed. Our results indicated that PMBN-A.Her2-GA is an anionic nanostructure with an appropriate form and capable of being applied in cancer therapy. Subsequently, cytotoxicity analysis revealed an improved anti-proliferative effect of GA-A.

In this article, GA-A is used for the first time as a natural agent for targeting breast cancer cells based on the newly developed nano carrier as a targeted DDS.

A designed cyclic peptide based on Trastuzumab used to construct peptide-drug conjugates for its HER2-targeting ability

Human epidermal growth factor receptor 2 (HER2) has been recognized as an important therapeutic target for its overexpression in many cancers. Trastuzumab is a monoclonal antibody targeting HER2, which has been approved by FDA to treat HER2-positive cancer. In this research, cyclic peptide Cyclo-GCGPep1 was designed based on the binding mode between antibody and HER2 protein in silico, which has been confirmed possessing good affinity with HER2. Cyclo-GCGPep1 was also used to construct peptide-drug conjugates with Camptothecin. Biological evaluations demonstrated that Conjugate 1 has a good antiproliferative activity on SK-BR-3 and NCI-N87 cells. Conjugate 1 retained the pro-apoptotic and Topo I inhibitory ability of Camptothecin. Meanwhile, it has good targeting ability towards HER2-positive cells with the help of Cyclo-GCGPep1. It also has better permeability in the tumor spheroid model than Camptothecin. In summary, the design of cyclic peptide derived from antibody is of significance for the discovery of targeting peptides and Conjugate 1 is expected as a good therapeutic agent for HER2-positive cancers.

Optimization of Nanoparticles for Smart Drug Delivery: A Review

Nanoparticle delivery systems have good application prospects in the treatment of various diseases, especially in cancer treatment. The effect of drug delivery is regulated by the properties of nanoparticles. There have been many studies focusing on optimizing the structure of nanoparticles in recent years, and a series of achievements have been made. This review summarizes the optimization strategies of nanoparticles from three aspects-improving biocompatibility, increasing the targeting efficiency of nanoparticles, and improving the drug loading rate of nanoparticles-aiming to provide some theoretical reference for the subsequent drug delivery of nanoparticles.

Valproic Acid and Breast Cancer: State of the Art in 2021

Valproic acid (2-propylpentanoic acid, VPA) is a short-chain fatty acid, a member of the group of histone deacetylase inhibitors (HDIs). VPA has been successfully used in the treatment of epilepsy, bipolar disorders, and schizophrenia for over 50 years. Numerous in vitro and in vivo pre-clinical studies suggest that this well-known anticonvulsant drug significantly inhibits cancer cell proliferation by modulating multiple signaling pathways. Breast cancer (BC) is the most common malignancy affecting women worldwide. Despite significant progress in the treatment of BC, serious adverse effects, high toxicity to normal cells, and the occurrence of multi-drug resistance (MDR) still limit the effective therapy of BC patients. Thus, new agents which improve the effectiveness of currently used methods, decrease the emergence of MDR, and increase disease-free survival are highly needed. This review focuses on in vitro and in vivo experimental data on VPA, applied individually or in combination with other anti-cancer agents, in the treatment of different histological subtypes of BC.

Nature-Inspired Nanoparticles as Paclitaxel Targeted Carrier for the Treatment of HER2-Positive Breast Cancer

Despite the advances made in the fight against HER2-positive breast cancer, the need for less toxic therapies and strategies that avoid the apparition of resistances is indisputable. For this reason, a targeted nanovehicle for paclitaxel and trastuzumab, used in the first-line treatment of this subtype of breast cancer, had already been developed in a previous study. It yielded good results in vitro but, with the aim of further reducing paclitaxel effective dose and its side effects, a novel drug delivery system was prepared in this work. Thus, polydopamine nanoparticles, which are gaining popularity in cancer nanomedicine, were novelty loaded with paclitaxel and trastuzumab. The effectiveness and selectivity of the nanoparticles obtained were validated in vitro with different HER2-overexpressing tumor and stromal cell lines. These nanoparticles showed more remarkable antitumor activity than the nanosystem previously designed and, in addition, to affect stromal cell viability rate less than the parent drug. Moreover, loaded polydopamine nanoparticles, which notably increased the number of apoptotic HER2-positive breast cancer cells after treatment, also maintained an efficient antineoplastic effect when validated in tumor spheroids. Thereby, these bioinspired nanoparticles charged with both trastuzumab and paclitaxel may represent an excellent approach to improve current HER2-positive breast cancer therapies.

Current updates on precision therapy for breast cancer associated brain metastasis: Emphasis on combination therapy

Cancer therapies have undergone a tremendous progress over the past decade. Precision medicine provides a more tailored approach, making the combination of existing therapies more precise. Different types of cancers are characterized by unique biomarkers that are targeted using various genomic approaches by clinicians and companies worldwide to achieve efficient treatment with minimal side effects. Precision medicine has two broad approaches namely stratified and personalized medicine. The driver mutations could vary within a subtype while the same driver mutations could be found across different subtypes. Precision medicine has recently gained a lot of importance for breast cancer therapy. Various kinds of mutations like hotspot mutations, gene alterations, gene amplification mutations are targeted to design a more specific therapy. Apart from these known gene mutations there are various unknown mutations. Thus, tumor heterogeneity can pose a challenge to precision medicine. For breast cancer, one of the most successful models developed in case of precision medicine is the anti-HER2 therapies as HER2 was considered to have the worst prognosis being highly malignant. But now due to the advent of HER2 receptor targeted therapies, it has a good prognosis. Moreover, precision medicine helps in identifying if the drug molecules being used for the treatment of one kind of cancer can be beneficial in the treatment of another kind of cancer as well, considering the signaling pathways and machinery is similar in most of the cancers. This reduces the time for new drug development and is economically more feasible. Precision medicine will prove to be very advantageous in case of brain metastasis.

Applications of natural product-derived carbon dots in cancer biology

Natural products have contributed conspicuously to the development of innovative nanomedicines. Hence, the interface between nanomaterial science and plant natural products may bestow comprehensive diagnostic and therapeutic strategies for tackling diseases such as cancer and neurological disorders. Natural product-derived carbon dots (NPdCDs) have revealed noteworthy attributes in the fields of cancer theranostics, microbial imaging, drug sensing and drug delivery. As plants consist of a cocktail of bioactive phytomolecules, the NPdCDs can be anticipated to have medicinal properties, biocompatibility, photo-stability and easy functionalization. NPdCDs have wide-ranging applications. The primary objective of this review is to comment on recent developments in the use of NPdCDs, with special reference to their application in cancer biology. The future of the use of NPdCDs has also been considered.