Co-delivery of VEGF siRNA and Etoposide for Enhanced Anti-angiogenesis and Anti-proliferation Effect via Multi-functional Nanoparticles for Orthotopic Non-Small Cell Lung Cancer Treatment

Exosomal circPVT1 promotes angiogenesis in laryngeal cancer by activating the Rap1b-VEGFR2 signaling pathway

Laryngeal cancer (LC) is the second most common head and neck cancer and has a decreasing 5-year survival rate worldwide. Circular RNAs (circRNAs) regulate cancer development in diverse ways based on their distinct biogenesis mechanisms and expansive regulatory roles. However, currently, there is little research on how exosomal circRNAs are involved in the development of LC. Here, we demonstrated that circPVT1, a circRNA derived from the well-studied long noncoding RNA PVT1, is correlated with disease progression in LC and promotes angiogenesis both in vivo and in vitro. Mechanistically, circPVT1 is loaded into LC cell-secreted exosomes and taken up by vascular epithelium cells. By sponging miR-30c-5p, exosomal circPVT1 promotes Rap1b expression, which dramatically enhances vascular endothelial growth factor receptor 2 and the phosphatidylinositol 3-kinase (PI3K)/AKT pathway activation, ultimately resulting in the induction of angiogenesis. Furthermore, our xenograft models demonstrated that the combination of short hairpin RNA-circPVT1 and cetuximab showed high efficacy in inhibiting tumor growth and angiogenesis. Collectively, these findings uncover a novel mechanism of exosomal circRNA-mediated angiogenesis modulation and provide a preclinical rationale for testing this analogous combination in patients with LC.

Advances in tumor vascular growth inhibition

Tumor growth and metastasis require neovascularization, which is dependent on a complex array of factors, such as the production of various pro-angiogenic factors by tumor cells, intercellular signaling, and stromal remodeling. The hypoxic, acidic tumor microenvironment is not only conducive to tumor cell proliferation, but also disrupts the equilibrium of angiogenic factors, leading to vascular heterogeneity, which further promotes tumor development and metastasis. Anti-angiogenic strategies to inhibit tumor angiogenesis has, therefore, become an important focus for anti-tumor therapy. The traditional approach involves the use of anti-angiogenic drugs to inhibit tumor neovascularization by targeting upstream and downstream angiogenesis-related pathways or pro-angiogenic factors, thereby inhibiting tumor growth and metastasis. This review explores the mechanisms involved in tumor angiogenesis and summarizes currently used anti-angiogenic drugs, including monoclonal antibody, and small-molecule inhibitors, as well as the progress and challenges associated with their use in anti-tumor therapy. It also outlines the opportunities and challenges of treating tumors using more advanced anti-angiogenic strategies, such as immunotherapy and nanomaterials.

Current advance of nanotechnology in diagnosis and treatment for malignant tumors

Cancer remains a significant risk to human health. Nanomedicine is a new multidisciplinary field that is garnering a lot of interest and investigation. Nanomedicine shows great potential for cancer diagnosis and treatment. Specifically engineered nanoparticles can be employed as contrast agents in cancer diagnostics to enable high sensitivity and high-resolution tumor detection by imaging examinations. Novel approaches for tumor labeling and detection are also made possible by the use of nanoprobes and nanobiosensors. The achievement of targeted medication delivery in cancer therapy can be accomplished through the rational design and manufacture of nanodrug carriers. Nanoparticles have the capability to effectively transport medications or gene fragments to tumor tissues via passive or active targeting processes, thus enhancing treatment outcomes while minimizing harm to healthy tissues. Simultaneously, nanoparticles can be employed in the context of radiation sensitization and photothermal therapy to enhance the therapeutic efficacy of malignant tumors. This review presents a literature overview and summary of how nanotechnology is used in the diagnosis and treatment of malignant tumors. According to oncological diseases originating from different systems of the body and combining the pathophysiological features of cancers at different sites, we review the most recent developments in nanotechnology applications. Finally, we briefly discuss the prospects and challenges of nanotechnology in cancer.

Nanoparticle-mediated metronomic chemotherapy in cancer: A paradigm of precision and persistence

Current methods of cancer therapy have demonstrated enormous potential in tumor inhibition. However, a high dosage regimen of chemotherapy results in various complications which affect the normal body cells. Tumor cells also develop resistance against the prescribed drugs in the whole treatment regimen increasing the risk of cancer relapse. Metronomic chemotherapy is a modern treatment method that involves administering drugs at low doses continuously, allowing the drug sufficient time to take its effect. This method ensures that the toxicity of the drugs is to a minimum in comparison to conventional chemotherapy. Nanoparticles have shown efficacy in delivering drugs to the tumor cells in various cancer therapies. Combining nanoparticles with metronomic chemotherapy can yield better treatment results. This combination stimulates the immune system, improving cancer cells recognition by immune cells. Evidence from clinical and pre-clinical trials supports the use of metronomic delivery for drug-loaded nanoparticles. This review focuses on the functionalization of nanoparticles for improved drug delivery and inhibition of tumor growth. It emphasizes the mechanisms of metronomic chemotherapy and its conjunction with nanotechnology. Additionally, it explores tumor progression and the current methods of chemotherapy. The challenges associated with nano-based metronomic chemotherapy are outlined, paving the way for prospects in this dynamic field.

Muscone abrogates breast cancer progression through tumor angiogenic suppression via VEGF/PI3K/Akt/MAPK signaling pathways

BACKGROUND

Angiogenesis strongly reflects poor breast cancer outcome and an important contributor to breast cancer (BC) metastasis; therefore, anti-angiogenic intervention is a potential tool for cancer treatment. However, currently used antibodies against vascular endothelial growth factor A (VEGFA) or inhibitors that target the VEGFA receptor are not effective due to weak penetration and low efficiency. Herein, we assessed the anti-BC angiogenic role of muscone, a natural bioactive musk constituent, and explored possible anti-cancer mechanisms of this compound.

METHODS

CCK-8, EdU, scratch and Transwell assessments were employed to detect the muscone-mediated regulation of breast cancer (BC) and human umbilical vein endothelial cells (HUVECs) proliferation and migration. Tube formation, matrigel plug assay and zebrafish assay were employed for assessment of regulation of tumor angiogenesis by muscone. In vivo xenograft mouse model was constructed to compare microvessel density (MVD), vascular leakage, vascular maturation and function in muscone-treated or untreated mice. RNA sequencing was performed for gene screening, and Western blot verified the effect of the VEGFA-VEGFR2 pathway on BC angiogenic inhibition by muscone.

RESULTS

Based on our findings, muscone suppressed BC progression via tumor angiogenic inhibition in cellular and animal models. Functionally, muscone inhibited BC cell proliferation and migration as well as tumor cell-conditioned medium-based endothelial cell proliferation and migration. Muscone exhibited a strong suppressive influence on tumor vasculature in cellular and animal models. It abrogated tumor cell growth in a xenograft BC mouse model and minimized tumor microvessel density and hypoxia, and increased vascular wall cell coverage and perfusion. Regarding the mechanism of action, we found that muscone suppressed phosphorylation of members of the VEGF/PI3K/Akt/MAPK axis, and it worked synergistically with a VEGFR2 inhibitor, an Akt inhibitor, and a MAPK inhibitor to further inhibit tube formation.

CONCLUSION

Overall, our results demonstrate that muscone may proficiently suppress tumor angiogenesis via modulation of the VEGF/PI3K/Akt/MAPK axis, facilitating its candidacy as a natural small molecule drug for BC treatment.

Nanotechnological Approaches to Enhance the Potential of α-Lipoic Acid for Application in the Clinic

α-lipoic acid is a naturally occurring compound with potent antioxidant properties that helps protect cells and tissues from oxidative stress. Its incorporation into nanoplatforms can affect factors like bioavailability, stability, reactivity, and targeted delivery. Nanoformulations of α-lipoic acid can significantly enhance its solubility and absorption, making it more bioavailable. While α-lipoic acid can be prone to degradation in its free form, encapsulation within nanoparticles ensures its stability over time, and its release in a controlled and sustained manner to the targeted tissues and cells. In addition, α-lipoic acid can be combined with other compounds, such as other antioxidants, drugs, or nanomaterials, to create synergistic effects that enhance their overall therapeutic benefits or hinder their potential cytotoxicity. This review outlines the advantages and drawbacks associated with the use of α-lipoic acid, as well as various nanotechnological approaches employed to enhance its therapeutic effectiveness, whether alone or in combination with other bioactive agents. Furthermore, it describes the engineering of α-lipoic acid to produce poly(α-lipoic acid) nanoparticles, which hold promise as an effective drug delivery system.

Extracellular vesicles derived from dendritic cells loaded with VEGF-A siRNA and doxorubicin reduce glioma angiogenesis in vitro

BACKGROUND

Numerous attempts have been devoted to designing anti-angiogenic agents as a strategy to slow tumor growth and progression. Clinical applications of conventional anti-angiogenic agents face some challenges, e.g., off-target effects for TKIs and also low solid tumor penetration for mAbs. Furthermore, although anti-angiogenic therapy provides a normalization window for better chemo-RT response, in long-term treatments, tumor hypoxia as a result of total removal of VEGF-A by mAbs from the TME or complete blockade of TK receptors induces over-activation of compensatory angiogenic pathways, causing escape. Herein, we investigate the efficacy of si-DOX-DC-EVs to reduce glioma angiogenesis and invasiveness.

METHODS

Mature DCs were generated from PBMC and EVs were isolated from the DCs culture media. siRNA and Doxorubicin were loaded into EVs by EP and incubation. Afterward, the uptake of DC-EVs was assessed by flow cytometry, and the subcellular localization of EVs was tested by confocal imaging. Tube formation assay was performed to assess the efficacy of si-DOX-DC-EVs to reduce tumor angiogenesis which was analyzed by DHM. Morphometric analysis of apoptotic cells was performed by DHM and confocal imaging and further, ELISA was performed for hypoxia-related and angiogenic cytokines. The impact of our theranostic system "si-DOX-DC-MVs" on the formation of vascular mimics, colonies, and invasion of C6 cells was checked in vitro. Afterward, orthotropic rat models of glioma were generated and the optimal administration route was selected by in vivo fluorescent analysis. Then, the microvessel density, vimentin expression, and accumulation of immune cells in tumoral tissues were assessed by IHC. Finally, necropsy and autopsy analyses were performed to check the safety of our theranostic agent.

RESULTS

DC-EVs loaded with si-DOX-DC-EVs were successfully uptaken by cells with different subcellular trafficking for MVs and exosomes, reduced tumor angiogenesis in DHM analysis, and induced apoptosis in tumoral cells. Moreover, using DHM, we performed a detailed label-free analysis of tip cells which suggested that the tip cells in si-DC-MV treatments lost their geometrical migration capacity to form tube-like structures. Furthermore, the ELISAs performed highlighted that there is a mild overactivation of compensatory Tie2/Ang2 pathway after VEGF-A blockade which confers with severe hypoxia and sustains normal angiogenesis which is the optimal goal of anti-angiogenesis therapy for cancer to avoid resistance.The results of our VM analyses indicated that si-DOX-DC-MVs completely inhibited VM process. Moreover, the invasion, migration, and colony formation of the C6 cells treated with si-DOX-MVs were the least among all treatments. IN was the optimal route of administration. The MVD analyses indicated that si-DOX-DC-MVs reduced the number of tumoral microvessels and normalized vessel morphology. Intense CD8+ T cells were observed near the tumoral vessels in the si-DOX-DC-MVs group and with minimal activation of MT (low Vimentin expression). Necropsy and toxicology results proved that the theranostic system proposed is safe.

CONCLUSIONS

DC-EVs loaded with VEGF-A siRNA and Doxorubicin were more potent than BV alone as a multi-disciplinary strategy that combats glioma growth by cytotoxic impacts of DOX and inhibits angiogenesis by VEGF-A siRNAs with excess immunologic benefits from DC-EVs. This next-generation anti-angiogenic agent normalizes tumor vessel density rather than extensively eliminating tumor vessels causing hypoxia and mesenchymal transition.

Engineering aspects of lipid-based delivery systems: In vivo gene delivery, safety criteria, and translation strategies

Defects in the genome cause genetic diseases and can be treated with gene therapy. Due to the limitations encountered in gene delivery, lipid-based supramolecular colloidal materials have emerged as promising gene carrier systems. In their non-functionalized form, lipid nanoparticles often demonstrate lower transgene expression efficiency, leading to suboptimal therapeutic outcomes, specifically through reduced percentages of cells expressing the transgene. Due to chemically active substituents, the engineering of delivery systems for genetic drugs with specific chemical ligands steps forward as an innovative strategy to tackle the drawbacks and enhance their therapeutic efficacy. Despite intense investigations into functionalization strategies, the clinical outcome of such therapies still needs to be improved. Here, we highlight and comprehensively review engineering aspects for functionalizing lipid-based delivery systems and their therapeutic efficacy for developing novel genetic cargoes to provide a full snapshot of the translation from the bench to the clinics. We outline existing challenges in the delivery and internalization processes and narrate recent advances in the functionalization of lipid-based delivery systems for nucleic acids to enhance their therapeutic efficacy and safety. Moreover, we address clinical trials using these vectors to expand their clinical use and principal safety concerns.

Dual pH/redox-responsive hyperbranched polymeric nanocarriers with TME-trigger size shrinkage and charge reversible ability for amplified chemotherapy of breast cancer

A novel pH/redox-responsive hyperbranched MeO-PEG-b-(NIPAAm-co-PBAE) nanoparticles (NPs) were designed with size shrinkage and charge-reversible potential for targeted delivery of docetaxel (DTX) to MDA-MB-231 cell lines. In the tumor microenvironment (TME), amine protonation induces charge reversal and disulfide bond cleavage under high TME GSH concentration causing size shrinkage, improved deep tumor penetration, and active targeting of the therapeutic agents. These nano drug delivery systems (NDDSs) significantly promoted cancer cell uptake (~ 100% at 0.5 h), facilitating site-specific delivery and deep tumor penetration. The MTT assay revealed significantly higher cytotoxicity (P value < 0.0001) for DTX-loaded NPs compared to free DTX. Cell cycle analysis revealed G2/M (58.3 ± 2.1%) and S (21.5 ± 1.3%) arrest for DTX-loaded NPs, while free DTX caused G2/M (67.9 ± 1.1%) and sub-G1 (10.3 ± 0.8%) arrest. DTX-loaded NPs induced higher apoptosis (P value < 0.001) in MDA-MB-231 cells (71.5 ± 2.8%) compared to free DTX (42.3 ± 3.1%). Western blotting and RT-PCR assays confirmed significant up-regulation of protein levels and apoptotic genes by DTX-loaded NPs compared to free DTX. In conclusion, TME-responsive charge reversal and size-shrinkable smart NDDSs designed based on low pH, and high glutathione (GSH), offer more effective site-specific delivery of therapeutic agents to tumors.

Tumor microenvironment reprogramming by nanomedicine to enhance the effect of tumor immunotherapy

With the rapid development of the fields of tumor biology and immunology, tumor immunotherapy has been used in clinical practice and has demonstrated significant therapeutic potential, particularly for treating tumors that do not respond to standard treatment options. Despite its advances, immunotherapy still has limitations, such as poor clinical response rates and differences in individual patient responses, largely because tumor tissues have strong immunosuppressive microenvironments. Many tumors have a tumor microenvironment (TME) that is characterized by hypoxia, low pH, and substantial numbers of immunosuppressive cells, and these are the main factors limiting the efficacy of antitumor immunotherapy. The TME is crucial to the occurrence, growth, and metastasis of tumors. Therefore, numerous studies have been devoted to improving the effects of immunotherapy by remodeling the TME. Effective regulation of the TME and reversal of immunosuppressive conditions are effective strategies for improving tumor immunotherapy. The use of multidrug combinations to improve the TME is an efficient way to enhance antitumor immune efficacy. However, the inability to effectively target drugs decreases therapeutic effects and causes toxic side effects. Nanodrug delivery carriers have the advantageous ability to enhance drug bioavailability and improve drug targeting. Importantly, they can also regulate the TME and deliver large or small therapeutic molecules to decrease the inhibitory effect of the TME on immune cells. Therefore, nanomedicine has great potential for reprogramming immunosuppressive microenvironments and represents a new immunotherapeutic strategy. Therefore, this article reviews strategies for improving the TME and summarizes research on synergistic nanomedicine approaches that enhance the efficacy of tumor immunotherapy.

Personalized Cancer Nanomedicine: Overcoming Biological Barriers for Intracellular Delivery of Biopharmaceuticals

The success of personalized medicine in oncology relies on using highly effective and precise therapeutic modalities such as small interfering RNA (siRNA) and monoclonal antibodies (mAbs). Unfortunately, the clinical exploitation of these biological drugs has encountered obstacles in overcoming intricate biological barriers. Drug delivery technologies represent a plausible strategy to overcome such barriers, ultimately facilitating the access to intracellular domains. Here, an overview of the current landscape on how nanotechnology has dealt with protein corona phenomena as a first and determinant biological barrier is presented. This continues with the analysis of strategies facilitating access to the tumor, along with conceivable methods for enhanced tumor penetration. As a final step, the cellular barriers that nanocarriers must confront in order for their biological cargo to reach their target are deeply analyzed. This review concludes with a critical analysis and future perspectives of the translational advances in personalized oncological nanomedicine.

Targeted anti-cancer therapy: Co-delivery of VEGF siRNA and Phenethyl isothiocyanate (PEITC) via cRGD-modified lipid nanoparticles for enhanced anti-angiogenic efficacy

Anti-tumor angiogenesis therapy, targeting the suppression of blood vessel growth in tumors, presents a potent approach in the battle against cancer. Traditional therapies have primarily concentrated on single-target techniques, with a specific emphasis on targeting the vascular endothelial growth factor, but have not reached ideal therapeutic efficacy. In response to this issue, our study introduced a novel nanoparticle system known as CS-siRNA/PEITC&L-cRGD NPs. These chitosan-based nanoparticles have been recognized for their excellent biocompatibility and ability to deliver genes. To enhance their targeted delivery capability, they were combined with a cyclic RGD peptide (cRGD). Targeted co-delivery of gene and chemotherapeutic agents was achieved through the use of a negatively charged lipid shell and cRGD, which possesses high affinity for integrin αvβ3 overexpressed in tumor cells and neovasculature. In this multifaceted approach, co-delivery of VEGF siRNA and phenethyl isothiocyanate (PEITC) was employed to target both tumor vascular endothelial cells and tumor cells simultaneously. The co-delivery of VEGF siRNA and PEITC could achieve precise silencing of VEGF, inhibit the accumulation of HIF-1α under hypoxic conditions, and induce apoptosis in tumor cells. In summary, we have successfully developed a nanoparticle delivery platform that utilizes a dual mechanism of action of anti-tumor angiogenesis and pro-tumor apoptosis, which provides a robust and potent strategy for the delivery of anti-cancer therapeutics.

A critical review on metal-organic frameworks (MOFs) based nanomaterials for biomedical applications: Designing, recent trends, challenges, and prospects

Nanomaterials (NMs) have garnered significant attention in recent decades due to their versatile applications in a wide range of fields. Thanks to their tiny size, enhanced surface modifications, impressive volume-to-surface area ratio, magnetic properties, and customized optical dispersion. NMs experienced an incredible upsurge in biomedical applications including diagnostics, therapeutics, and drug delivery. This minireview will focus on notable examples of NMs that tackle important issues, demonstrating various aspects such as their design, synthesis, morphology, classification, and use in cutting-edge applications. Furthermore, we have classified and outlined the distinctive characteristics of the advanced NMs as nanoscale particles and hybrid NMs. Meanwhile, we emphasize the incredible potential of metal-organic frameworks (MOFs), a highly versatile group of NMs. These MOFs have gained recognition as promising candidates for a wide range of bio-applications, including bioimaging, biosensing, antiviral therapy, anticancer therapy, nanomedicines, theranostics, immunotherapy, photodynamic therapy, photothermal therapy, gene therapy, and drug delivery. Although advanced NMs have shown great potential in the biomedical field, their use in clinical applications is still limited by issues such as stability, cytotoxicity, biocompatibility, and health concerns. This review article provides a thorough analysis offering valuable insights for researchers investigating to explore new design, development, and expansion opportunities. Remarkably, we ponder the prospects of NMs and nanocomposites in conjunction with current technology.

A review of chitosan in gene therapy: Developments and challenges

Gene therapy, as a revolutionary treatment, has been gaining more and more attention. The key to gene therapy is the selection of suitable vectors for protection of exogenous nucleic acid molecules and enabling their specific release in target cells. While viral vectors have been widely used in researches, non-viral vectors are receiving more attention due to its advantages. Chitosan (CS) has been widely used as non-viral organic gene carrier because of its good biocompatibility and its ability to load large amounts of nucleic acids. This paper summarizes and evaluates the potential of chitosan and its derivatives as gene delivery vector materials, along with factors influencing transfection efficiency, performance evaluation, ways to optimize infectious efficiency, and the current main research development directions. Additionally, it provides an outlook on its future prospects.

Role of Angiogenesis and Its Biomarkers in Development of Targeted Tumor Therapies

Angiogenesis plays a significant role in the human body, from wound healing to tumor progression. "Angiogenic switch" indicates a time-restricted event where the imbalance between pro- and antiangiogenic factors results in the transition from prevascular hyperplasia to outgrowing vascularized tumor, which eventually leads to the malignant cancer progression. In the last decade, molecular players, i.e., angiogenic biomarkers and underlying molecular pathways involved in tumorigenesis, have been intensely investigated. Disrupting the initiation and halting the progression of angiogenesis by targeting these biomarkers and molecular pathways has been considered as a potential treatment approach for tumor angiogenesis. This review discusses the currently known biomarkers and available antiangiogenic therapies in cancer, i.e., monoclonal antibodies, aptamers, small molecular inhibitors, miRNAs, siRNAs, angiostatin, endostatin, and melatonin analogues, either approved by the U.S. Food and Drug Administration or currently under clinical and preclinical investigations.

Multifunctional nanoparticle-mediated combining therapy for human diseases

Combining existing drug therapy is essential in developing new therapeutic agents in disease prevention and treatment. In preclinical investigations, combined effect of certain known drugs has been well established in treating extensive human diseases. Attributed to synergistic effects by targeting various disease pathways and advantages, such as reduced administration dose, decreased toxicity, and alleviated drug resistance, combinatorial treatment is now being pursued by delivering therapeutic agents to combat major clinical illnesses, such as cancer, atherosclerosis, pulmonary hypertension, myocarditis, rheumatoid arthritis, inflammatory bowel disease, metabolic disorders and neurodegenerative diseases. Combinatorial therapy involves combining or co-delivering two or more drugs for treating a specific disease. Nanoparticle (NP)-mediated drug delivery systems, i.e., liposomal NPs, polymeric NPs and nanocrystals, are of great interest in combinatorial therapy for a wide range of disorders due to targeted drug delivery, extended drug release, and higher drug stability to avoid rapid clearance at infected areas. This review summarizes various targets of diseases, preclinical or clinically approved drug combinations and the development of multifunctional NPs for combining therapy and emphasizes combinatorial therapeutic strategies based on drug delivery for treating severe clinical diseases. Ultimately, we discuss the challenging of developing NP-codelivery and translation and provide potential approaches to address the limitations. This review offers a comprehensive overview for recent cutting-edge and challenging in developing NP-mediated combination therapy for human diseases.

Recent advancements in the targeted delivery of etoposide nanomedicine for cancer therapy: A comprehensive review

Etoposide (ETO), a popular anticancer drug that inhibits topoisomerase II enzymes, may be administered more effectively and efficiently due to nanomedicine. The therapeutic application of ETO is constrained by its limited solubility, weak absorption, and severe side effects. This article summarizes substantial progress made in the development of ETO nanomedicine for the treatment of cancer. It discusses various organic and inorganic nanostructures used to load or affix ETOs, such as lipids, liposomes, polymeric nanoparticles (NPs), dendrimers, micelles, gold NPs, iron oxide NPs, and silica NPs. In addition, it evaluates the structural properties of these nanostructures, such as their size, zeta potential, encapsulation efficiency, and drug release mechanism, as well as their in vitro or in vivo performance. The article also emphasizes the co-delivery of ETO with other medications or agents to produce synergistic effects or combat drug resistance in the treatment of cancer. It concludes with a discussion of the challenges and potential avenues for clinical translation of ETO nanomedicine.

Recent Advances in Mesoporous Silica Nanoparticles Delivering siRNA for Cancer Treatment

Silencing genes using small interfering (si) RNA is a promising strategy for treating cancer. However, the curative effect of siRNA is severely constrained by low serum stability and cell membrane permeability. Therefore, improving the delivery efficiency of siRNA for cancer treatment is a research hotspot. Recently, mesoporous silica nanoparticles (MSNs) have emerged as bright delivery vehicles for nucleic acid drugs. A comprehensive understanding of the design of MSN-based vectors is crucial for the application of siRNA in cancer therapy. We discuss several surface-functionalized MSNs' advancements as effective siRNA delivery vehicles in this paper. The advantages of using MSNs for siRNA loading regarding considerations of different shapes, various options for surface functionalization, and customizable pore sizes are highlighted. We discuss the recent investigations into strategies that efficiently improve cellular uptake, facilitate endosomal escape, and promote cargo dissociation from the MSNs for enhanced intracellular siRNA delivery. Also, particular attention was paid to the exciting progress made by combining RNAi with other therapies to improve cancer therapeutic outcomes.

Non-coding RNA-directed therapeutics in lung cancer: Delivery technologies and clinical applications

Lung cancer is one of the most aggressive and deadliest health threats. There has been an increasing interest in non-coding RNA (ncRNA) recently, especially in the areas of carcinogenesis and tumour progression. However, ncRNA-directed therapies are still encountering obstacles on their way to the clinic. In the present article, we provide an overview on the potential of targeting ncRNA in the treatment of lung cancer. Then, we discuss the delivery challenges and recent approaches enabling the delivery of ncRNA-directed therapies to the lung cancer cells, where we illuminate some advanced technologies including chemically-modified oligonucleotides, nuclear targeting, and three-dimensional in vitro models. Furthermore, advanced non-viral delivery systems recruiting nanoparticles, biomimetic delivery systems, and extracellular vesicles are also highlighted. Lastly, the challenges limiting the clinical trials on the therapeutic targeting of ncRNAs in lung cancer and future directions to tackle them are explored.

Research progress of siVEGF complex and their application in antiangiogenic therapy

Vascular endothelial growth factor (VEGF) is an important factor in the development of some diseases such as tumors, ocular neovascular disease and endometriosis. Inhibition of abnormal VEGF expression is one of the most effective means of treating these diseases. The resistance and side effects of currently used VEGF drugs limit their application. Herein, small interfering RNA for VEGF (siVEGF) are developed to inhibit VEGF expression at the genetic level by means of RNA interference. However, as a foreign substance entering the organism, siVEGF is prone to induce an immune response or mismatch, which adversely affects the organism. It is also subjected to enzymatic degradation and cell membrane blockage, which greatly reduces its therapeutic effect. Targeted siVEGF complexes are constructed by nanocarriers to avoid their clearance by the body and precisely target cells, exerting anti-vascular effects for the treatment of relevant diseases. In addition, some multifunctional complexes allow for the combination of siVEGF with other therapeutic tools to improve the treat efficiency of the disease. Therefore, this review describes the construction of the siVEGF complex, its mechanism of action, application in anti-blood therapy, and provides an outlook on its current problems and prospects.

Therapeutic m6A Eraser ALKBH5 mRNA-Loaded Exosome-Liposome Hybrid Nanoparticles Inhibit Progression of Colorectal Cancer in Preclinical Tumor Models

Although therapeutic targets have been developed for colorectal cancer (CRC) therapy, the therapeutic effects are not ideal and the survival rate for CRC patients remains poor. Therefore, it is crucial to recognize a specific target and develop an efficacious delivery system for CRC therapy. Herein, we demonstrate that reduced ALKBH5 mediates aberrant m⁶A modification and tumor progression in CRC. Mechanically, histone deacetylase 2-mediated H3K27 deacetylation inhibits ALKBH5 transcription in CRC, whereas ectopic ALKBH5 expression decreases tumorigenesis of CRC cells and protects mice from colitis-associated tumor development. Further, METTL14/ALKBH5/IGF2BPs combine to modulate JMJD8 stability in an m⁶A-dependent manner, which increases glycolysis and accelerates the development of CRC by enhancing the enzymatic activity of PKM2. Moreover, ALKBH5 mRNA-loaded folic acid-modified exosome-liposome hybrid nanoparticles were synthesized and significantly inhibit the progression of CRC in preclinical tumor models by modulating the ALKBH5/JMJD8/PKM2 axis and inhibiting glycolysis. Overall, our research confirms the crucial function of ALKBH5 in regulating the m⁶A status in CRC and provides a direct preclinical approach for using ALKBH5 mRNA nanotherapeutics for CRC.

Nanotechnology-empowered lung cancer therapy: From EMT role in cancer metastasis to application of nanoengineered structures for modulating growth and metastasis

Lung cancer is one of the leading causes of death in both males and females, and it is the first causes of cancer-related deaths. Chemotherapy, surgery and radiotherapy are conventional treatment of lung cancer and recently, immunotherapy has been also appeared as another therapeutic strategy for lung tumor. However, since previous treatments have not been successful in cancer therapy and improving prognosis and survival rate of lung tumor patients, new studies have focused on gene therapy and targeting underlying molecular pathways involved in lung cancer progression. Nanoparticles have been emerged in treatment of lung cancer that can mediate targeted delivery of drugs and genes. Nanoparticles protect drugs and genes against unexpected interactions in blood circulation and improve their circulation time. Nanoparticles can induce phototherapy in lung cancer ablation and mediating cell death. Nanoparticles can induce photothermal and photodynamic therapy in lung cancer. The nanostructures can impair metastasis of lung cancer and suppress EMT in improving drug sensitivity. Metastasis is one of the drawbacks observed in lung cancer that promotes migration of tumor cells and allows them to establish new colony in secondary site. EMT can occur in lung cancer and promotes tumor invasion. EMT is not certain to lung cancer and it can be observed in other human cancers, but since lung cancer has highest incidence rate, understanding EMT function in lung cancer is beneficial in improving prognosis of patients. EMT induction in lung cancer promotes tumor invasion and it can also lead to drug resistance and radio-resistance. Moreover, non-coding RNAs and pharmacological compounds can regulate EMT in lung cancer and EMT-TFs such as Twist and Slug are important modulators of lung cancer invasion that are discussed in current review.

A novel estrogen-targeted PEGylated liposome co-delivery oxaliplatin and paclitaxel for the treatment of ovarian cancer

Ovarian cancer is the second cause of death among gynecological malignancies. In this study, we designed a novel estrogen-targeted PEGylated liposome loaded with oxaliplatin and paclitaxel (ES-SSL-OXA/PTX) which could target estrogen receptor (ER) highly expressed on the surface of SKOV-3 cells to enhance therapeutic efficacy and reduce the side effects for SKOV-3 tumor therapy. ES-SSL-OXA/PTX was prepared by thin film hydration method and exhibited a uniform spherical morphology. Encapsulation efficiency (EE) were determined by HPLC method with the results of 44.10% for OXA and 65.85% for PTX. The mean particle size and polydispersity index (PDI) were 168.46 nm and 0.145, respectively. In vivo and in vitro targeting study confirmed that ES-SSL-OXA/PTX has optimum specific targeting ability. Meanwhile, In vitro and in vivo antitumor results of ES-SSL-OXA/PTX exhibited a superior antiproliferative effect on SKOV-3 cells and a stronger anti-tumor efficacy with the tumor inhibition rate of 85.24%. The pharmacokinetics results of ES-SSL-OXA/PTX showed a prolonged half-life time and a slowed clearance rate. The preliminary safety study of acute toxicity and long-term toxicity demonstrated ES-SSL-OXA/PTX exhibited a reduced toxicity profile. Based on the above results, ES-SSL-OXA/PTX could be a promising novel formulation for the treatment of ovarian cancer in future clinic.

The Small RNA Landscape in NSCLC: Current Therapeutic Applications and Progresses

Non-small-cell lung cancer (NSCLC) is the second most diagnosed type of malignancy and the first cause of cancer death worldwide. Despite recent advances, the treatment of choice for NSCLC patients remains to be chemotherapy, often showing very limited effectiveness with the frequent occurrence of drug-resistant phenotype and the lack of selectivity for tumor cells. Therefore, new effective and targeted therapeutics are needed. In this context, short RNA-based therapeutics, including Antisense Oligonucleotides (ASOs), microRNAs (miRNAs), short interfering (siRNA) and aptamers, represent a promising class of molecules. ASOs, miRNAs and siRNAs act by targeting and inhibiting specific mRNAs, thus showing an improved specificity compared to traditional anti-cancer drugs. Nucleic acid aptamers target and inhibit specific cancer-associated proteins, such as "nucleic acid antibodies". Aptamers are also able of receptor-mediated cell internalization, and therefore, they can be used as carriers of secondary agents giving the possibility of producing very highly specific and effective therapeutics. This review provides an overview of the proposed applications of small RNAs for NSCLC treatment, highlighting their advantageous features and recent advancements in the field.

siRNA-E6 sensitizes HPV-16-related cervical cancer through Oxaliplatin: an in vitro study on anti-cancer combination therapy

BACKGROUND

Persistent infection with high-risk Human papillomaviruses (HPV), such as hr-HPV-16 and hr-HPV-18, lead to cervical cancer, the fourth most common cancer in the world. In the present study, we investigated the alteration of E6 oncogene expression by E6-specific short interfering RNA (siRNA) combined with Oxaliplatin.

METHODS

The cervical cancer cell line, CaSki, was transfected with E6-siRNA, then treated with Oxaliplatin. The cellular genes, such as p53, MMP9, Nanog, and caspases expression, were assessed by quantitative real-time PCR. The cell death rate, cell cycle, and cell viability were assessed by Annexin V/PI staining, DAPI staining, and MTT test, respectively. Furthermore, colony formation assay and scratch test determined the stemness ability and cell metastasis, respectively.

RESULTS

Combination therapy increased the re-expression of genes involved in the p53-dependent apoptosis pathway (increase in apoptosis to 44.2%), and reduced stemness and metastasis ability compared to either siRNA or Oxaliplatin monotherapy. Together, our results demonstrate that E6-siRNA and Oxaliplatin combination increased the cervical cancer cells' sensitivity to Oxaliplatin and decreased the survival rate, proliferation, and metastasis, and consequently escalated apoptosis rate, induced cell cycle arrest in the sub-G1 stage, and reduced the chemotherapy drug dosage.

CONCLUSION

Inhibition of E6 oncogene expression and subsequent E6-siRNA with Oxaliplatin combination therapy could be a novel strategy for cervical cancer treatment.

Angiogenesis and immune checkpoint dual blockade: Opportunities and challenges for hepatocellular carcinoma therapy

The disease burden related to hepatocellular carcinoma (HCC) is increasing. Most HCC patients are diagnosed at the advanced stage and multikinase inhibitors have been the only treatment choice for them. Recently, the approval of immune checkpoint inhibitors (ICIs) has provided a new therapeutic strategy for HCC. It is noteworthy that the positive outcomes of the phase III clinical trial IMBrave150 [atezolizumab (anti-programmed cell death ligand 1 antibody) combined with bevacizumab (anti-vascular endothelial growth factor monoclonal antibody)], showed that overall survival and progression-free survival were significantly better with sorafenib. This combination therapy has become the new standard therapy for advanced HCC and has also attracted more attention in the treatment of HCC with anti-angiogenesis-immune combination therapy. Currently, the synergistic antitumor efficacy of this combination has been shown in many preclinical and clinical studies. In this review, we discuss the mechanism and clinical application of anti-angiogenics and immunotherapy in HCC, outline the relevant mechanism and rationality of the combined application of anti-angiogenics and ICIs, and point out the existing challenges of the combination therapy.

Current Advancements in Self-assembling Nanocarriers-Based siRNA Delivery for Cancer Therapy

Different therapeutic practices for treating cancers have significantly evolved to compensate and/or overcome the failures in conventional methodologies. The demonstrated potentiality in completely inhibiting the tumors and in preventing cancer relapse has made nucleic acids therapy (NAT)/gene therapy as an attractive practice. This has been made possible because NAT-based cancer treatments are highly focused on the fundamental mechanisms - i.e., silencing the expression of oncogenic genes responsible for producing abnormal proteins (via messenger RNAs (mRNAs)). However, the future clinical translation of NAT is majorly dependent upon the effective delivery of the exogenous nucleic acids (especially RNAs - e.g., short interfering RNAs (siRNAs) - herein called biological drugs). Moreover, nano-based vehicles (i.e., nanocarriers) are involved in delivering them to prevent degradation and undesired bioaccumulation while enhancing the stability of siRNAs. Herein, we have initially discussed about three major types of self-assembling nanocarriers (liposomes, polymeric nanoparticles and exosomes). Later, we have majorly reviewed recent developments in non-targeted/targeted nanocarriers for delivery of biological drugs (individual/dual) to silence the most important genes/mRNAs accountable for inducing protein abnormality. These proteins include polo-like kinase 1 (PLK1), survivin, vascular endothelial growth factor (VEGF), B-cell lymphoma/leukaemia-2 (Bcl-2) and multi-drug resistance (MDR). Besides, the consequent therapeutic effects on cancer growth, invasion and/or metastasis have also been discussed. Finally, we have comprehensively reviewed the improvements achieved in the cutting-edge cancer therapeutics while delivering siRNAs in combination with clinically approved chemotherapeutic drugs.

A Multifunctional Non-viral Vector for the Delivery of MTH1-targeted CRISPR/Cas9 System for Non-Small Cell Lung Cancer Therapy

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system adapted from bacteria is a programmable nuclease-based genome editing tool. The long-lasting effect of gene silencing or correction is beneficial in cancer treatment. Considering the need to broaden the practical application of this technology, highly efficient non-viral vectors are urgently required. We prepared a multifunctional non-viral vector that could actively target tumor cells and deliver CRISPR/Cas9 plasmids into nuclei of cancer cells. Protamine sulfate (PS) which contains nuclear localization sequence was utilized to condense plasmid DNA and facilitate nuclei-targeted delivery. Liposome-coated protein/DNA complex avoided the degradation of nuclease in blood circulation. The obtained PS@Lip/pCas9 was further modified with distearoyl phosphoethanolamine-polyethylene glycol-hyaluronic acid (HA) to endow the vector ability to actively target tumor cell. Results suggested that PS@HA-Lip could deliver CRISPR/Cas9 plasmids into nuclei of tumor cells and induce genome editing effect. With the disruption of MTH1 (mutT homolog1) gene, the growth of non-small cell lung cancer was inhibited. Moreover, cell apoptosis in tumor tissue was promoted, and liver metastasis of non-small cell lung cancer (NSCLC) was reduced. Our study has provided a therapeutic strategy targeting MTH1 gene for NSCLC therapy. STATEMENT OF SIGNIFICANCE: CRISPR/Cas9 as a powerful tool for genome editing has drawn much attention. The long-lasting effect possesses unique advantage in cancer treatment. Non-viral vectors have high loading capacity, high safety and low immunogenicity, playing an important role in CRISPR/Cas9 delivery. In our study, a multifunctional non-viral vector for the efficient delivery of CRISPR/Cas9 plasmid was constructed. With the active targeting ligand and nuclei-targeting component, the cargo was efficiently delivered into cell nuclei and exerted genome editing effect. By using this vector, we successfully inhibited the growth and induced the apoptosis of non-small cell lung cancer by disrupting MTH1 expression with good safety. Our work provided an efficient non-vial vector for CRISPR/Cas9 delivery and explored the possibility for cancer treatment.

Non-coding RNAs in lung cancer: emerging regulators of angiogenesis

Lung cancer is the second cancer and the leading cause of tumor-related mortality worldwide. Angiogenesis is a crucial hallmark of cancer development and a promising target in lung cancer. However, the anti-angiogenic drugs currently used in the clinic do not achieve long-term efficacy and are accompanied by severe adverse reactions. Therefore, the development of novel anti-angiogenic therapeutic approaches for lung cancer is urgently needed. Non-coding RNAs (ncRNAs) participate in multiple biological processes in cancers, including tumor angiogenesis. Many studies have demonstrated that ncRNAs play crucial roles in tumor angiogenesis. This review discusses the regulatory functions of different ncRNAs in lung cancer angiogenesis, focusing on the downstream targets and signaling pathways regulated by these ncRNAs. Additionally, given the recent trend towards utilizing ncRNAs as cancer therapeutics, we also discuss the tremendous potential applications of ncRNAs as biomarkers or novel anti-angiogenic tools in lung cancer.

Analyzing siRNA Concentration, Complexation and Stability in Cationic Dendriplexes by Stem-Loop Reverse Transcription-qPCR

RNA interference (RNAi) is a powerful therapeutic approach for messenger RNA (mRNA) level regulation in human cells. RNAi can be triggered by small interfering RNAs (siRNAs) which are delivered by non-viral carriers, e.g., dendriplexes. siRNA quantification inside carriers is essential in drug delivery system development. However, current siRNA measuring methods either are not very sensitive, only semi-quantitative or not specific towards intact target siRNA sequences. We present a novel reverse transcription real-time PCR (RT-qPCR)-based application for siRNA quantification in drug formulations. It enables specific and highly sensitive quantification of released, uncomplexed target siRNA and thus also indirect assessment of siRNA stability and concentration inside dendriplexes. We show that comparison with a dilution series allows for siRNA quantification, exclusively measuring intact target sequences. The limit of detection (LOD) was 4.2 pM (±0.2 pM) and the limit of quantification (LOQ) 77.8 pM (±13.4 pM) for uncomplexed siRNA. LOD and LOQ of dendriplex samples were 31.6 pM (±0 pM) and 44.4 pM (±9.0 pM), respectively. Unspecific non-target siRNA sequences did not decrease quantification accuracy when present in samples. As an example of use, we assessed siRNA complexation inside dendriplexes with varying nitrogen-to-phosphate ratios. Further, protection of siRNA inside dendriplexes from RNase A degradation was quantitatively compared to degradation of uncomplexed siRNA. This novel application for quantification of siRNA in drug delivery systems is an important tool for the development of new siRNA-based drugs and quality checks including drug stability measurements.

Novel Angiogenic Regulators and Anti-Angiogenesis Drugs Targeting Angiogenesis Signaling Pathways: Perspectives for Targeting Angiogenesis in Lung Cancer

Lung cancer growth is dependent on angiogenesis. In recent years, angiogenesis inhibitors have attracted more and more attention as potential lung cancer treatments. Current anti-angiogenic drugs targeting VEGF or receptor tyrosine kinases mainly inhibit tumor growth by reducing angiogenesis and blocking the energy supply of lung cancer cells. However, these drugs have limited efficiency, raising concerns about limited scope of action and mechanisms of patient resistance to existing drugs. Therefore, current basic research on angiogenic regulators has focused more on screening carcinogenic/anticancer genes, miRNAs, lncRNAs, proteins and other biomolecules capable of regulating the expression of specific targets in angiogenesis signaling pathways. In addition, new uses for existing drugs and new drug delivery systems have received increasing attention. In our article, we analyze the application status and research hotspots of angiogenesis inhibitors in lung cancer treatment as a reference for subsequent mechanistic research and drug development.

Recent Development of MOF-Based Photothermal Agent for Tumor Ablation

Metal-organic frameworks (MOFs) are 3D-architecture compounds of metal ions and organic molecules with sufficient and permanent porosity, showing great potential as a versatile platform to load various functional moieties to endow the hybrid materials with specific applications. Currently, a variety of photothermal nanometals have been embedded into organic ligands for integrating the unique photothermal effects with the merits of MOFs to improve their performances for cancer therapy. In this review, we have summarized a series of novel MOF-based photothermal materials for this unique therapeutic modality against tumors from three main aspects according to their chemical compositions and structures, i) metal-doped MOF, ii) organic-doped MOF, and iii) polymer-coated MOF. In addition, we have summarized the latest developments and characteristics of MOF-based photothermal agents, such as good biocompatibility, low toxicity, and responsive photothermal conversion without destroying the structure of hybrid photothermal agent. At last, we addressed the future perspectives of MOF-based photothermal agent in the field of phototherapy.

Charge reversal nano-systems for tumor therapy

Surface charge of biological and medical nanocarriers has been demonstrated to play an important role in cellular uptake. Owing to the unique physicochemical properties, charge-reversal delivery strategy has rapidly developed as a promising approach for drug delivery application, especially for cancer treatment. Charge-reversal nanocarriers are neutral/negatively charged at physiological conditions while could be triggered to positively charged by specific stimuli (i.e., pH, redox, ROS, enzyme, light or temperature) to achieve the prolonged blood circulation and enhanced tumor cellular uptake, thus to potentiate the antitumor effects of delivered therapeutic agents. In this review, we comprehensively summarized the recent advances of charge-reversal nanocarriers, including: (i) the effect of surface charge on cellular uptake; (ii) charge-conversion mechanisms responding to several specific stimuli; (iii) relation between the chemical structure and charge reversal activity; and (iv) polymeric materials that are commonly applied in the charge-reversal delivery systems.

Tumor vasculature-targeting nanomedicines

Uncontrolled tumor growth and subsequent distant metastasis are highly dependent on an adequate nutrient supply from tumor blood vessels, which have relatively different pathophysiological characteristics from those of normal vasculature. Obviously, strategies targeting tumor vasculature, such as anti-angiogenic drugs and vascular disrupting agents, are attractive methods for cancer therapy. However, the off-target effects and high dose administration of these drug regimens critically restrict their clinical applications. In recent years, nanomedicines focused on tumor vasculature have been shown to be superior to traditional therapeutic methods and do not induce side effects. This review will first highlight the recent development of tumor vasculature-targeting nanomedicines from the following four aspects: 1) angiogenesis-inhibiting nanomedicines (AINs); 2) vasculature-disrupting nanomedicines (VDNs); 3) vasculature infarction nanomedicines (VINs); and 4) vasculature-regulating nanomedicines (VRNs). Furthermore, the design principles, limitations, and future directions are also discussed. STATEMENT OF SIGNIFICANCE: Based on the essential roles of tumor blood vessels, the therapeutic strategies targeting tumor vasculature have exhibited good clinical therapeutic outcomes. However, poor patient adherence to free drug administration limits their clinical usage. Nanomedicines have great potential to overcome the abovementioned obstacle. This review summarizes the tumor-vasculature targeting nanomedicines from four aspects: 1) angiogenesis-inhibiting nanomedicines (AINs); 2) vasculature-disrupting nanomedicines (VDNs); 3) vasculature infarction nanomedicines (VINs); and 4) vasculature regulating nanomedicines (VRNs). In addition, this review provides perspectives on this research field.

Lactate Consumption via Cascaded Enzymes Combined VEGF siRNA for Synergistic Anti-Proliferation and Anti-Angiogenesis Therapy of Tumors

Lactate, as the most abundant component with concentrations of 4-40 mm in tumors, contributes to the regulation of metabolic pathways, angiogenesis, and immunosuppression, exhibiting remarkable potential in cancer treatment. Therefore, a codelivery strategy that combined the cascaded enzymes Lactate oxidase/Catalase (LOx/CAT) and vascular endothelial growth factor (VEGF) siRNA (siVEGF) to suppress tumor proliferation and angiogenesis synergistically is creatively proposed. In brief, the cationic liposomes (LIP) encapsulated with LOx/CAT and siVEGF via hydrophilic interaction and electrostatic adsorption followed by coating with PEGylated phenylboronic acid (PP) is established (PPL@[LOX+CAT]). Moreover, a simple 3-aminophenylboronic acid (PBA)-shielded strategy via fructose (Fru) is applied to further enhance the targeting efficiency in the tumor site. The obtained co-encapsulated nanoparticles (NPs) can simultaneous intracellular release of LOx/CAT and siVEGF, and the collaborative use of LOx and CAT can promote lactate consumption even under a hypoxic tumor microenvironment (TME) without producing systemic toxicity. The combined application of lactate depletion and VEGF silencing demonstrated the efficient migration suppression of 4T1 cells in vitro and superior antitumor and antimetastatic properties in vivo. This work offers a promising tumor treatment strategy via integrating cascaded enzymes and gene therapy, and explores a promising therapy regimen for 4T1 triple-negative breast cancer.

Nanotechnology lights up the antitumor potency by combining chemotherapy with siRNA

Nanotechnology-based combination anticancer therapy offers novel approaches to overcome the limitations of single-agent administration. The emerging siRNA technology combined with chemotherapy has shown considerable promise in anticancer therapy. There are three main challenges in the fabrication of siRNA/chemotherapeutic drug co-loaded nanovectors: adequate cargo protection, precise targeted delivery, and site-specific cargo release. This review presents a summary of the nanosystems that have recently been developed for co-delivering siRNA and chemotherapeutic drugs. Their combined therapeutic effects are also discussed.

Emerging nanomedicine-based therapeutics for hematogenous metastatic cascade inhibition: Interfering with the crosstalk between "seed and soil"

Despite considerable progresses in cancer treatment, tumor metastasis is still a thorny issue, which leads to majority of cancer-related deaths. In hematogenous metastasis, the concept of “seed and soil” suggests that the crosstalk between cancer cells (seeds) and premetastatic niche (soil) facilitates tumor metastasis. Considerable efforts have been dedicated to inhibit the tumor metastatic cascade, which is a highly complicated process involving various pathways and biological events. Nonetheless, satisfactory therapeutic outcomes are rarely observed, since it is a great challenge to thwart this multi-phase process. Recent advances in nanotechnology-based drug delivery systems have shown great potential in the field of anti-metastasis, especially compared with conventional treatment methods, which are limited by serious side effects and poor efficacy. In this review, we summarized various factors involved in each phase of the metastatic cascade ranging from the metastasis initiation to colonization. Then we reviewed current approaches of targeting these factors to stifle the metastatic cascade, including modulating primary tumor microenvironment, targeting circulating tumor cells, regulating premetastatic niche and eliminating established metastasis. Additionally, we highlighted the multi-phase targeted drug delivery systems, which hold a better chance to inhibit metastasis. Besides, we demonstrated the limitation and future perspectives of nanomedicine-based anti-metastasis strategies.

Recent Advances in Tumor Targeting via EPR Effect for Cancer Treatment

Cancer causes the second-highest rate of death world-wide. A major shortcoming inherent in most of anticancer drugs is their lack of tumor selectivity. Nanodrugs for cancer therapy administered intravenously escape renal clearance, are unable to penetrate through tight endothelial junctions of normal blood vessels and remain at a high level in plasma. Over time, the concentration of nanodrugs builds up in tumors due to the EPR effect, reaching several times higher than that of plasma due to the lack of lymphatic drainage. This review will address in detail the progress and prospects of tumor-targeting via EPR effect for cancer therapy.

Tumor angiogenesis: Current challenges and therapeutic opportunities

Angiogenesis plays an important role in the development of cancer since it allows for the delivery of oxygen, nutrients, and growth factors as well as tumor dissemination to distant organs. Inhibition of angiogenesis is an important strategy for the prevention of multiple solid tumors that depend on cutting or at least reducing the blood supply to tumor micro-regions, resulting in pan-hypoxia and pan-necrosis within solid tumor tissues. These drugs are an important part of treatment for some types of cancer. As a stand-alone therapy, inhibition of tumor angiogenesis can arrest or halt tumor growth, but will not eliminate the tumor. Therefore, anti-angiogenic drugs in combinations with another anti-cancer treatment method, like chemotherapy, lead to being critical for optimum cancer patient outcomes. Over the last two decades, investigations have been made to improve the efficacy of anti-angiogenic drugs, recognize their potential in drug interactions, and come up with plausible explanations for possible treatment resistance. This review will offer an overview of the varying concepts of tumor angiogenesis, several important angiogenic factors; focus on the role of anti-angiogenesis strategies in cancer treatment.

Bio-Nanocarriers for Lung Cancer Management: Befriending the Barriers

Lung cancer is a complex thoracic malignancy developing consequential to aberrations in a myriad of molecular and biomolecular signaling pathways. It is one of the most lethal forms of cancers accounting to almost 1.8 million new annual incidences, bearing overall mortality to incidence ratio of 0.87. The dismal prognostic scenario at advanced stages of the disease and metastatic/resistant tumor cell populations stresses the requisite of advanced translational interdisciplinary interventions such as bionanotechnology. This review article deliberates insights and apprehensions on the recent prologue of nanobioengineering and bionanotechnology as an approach for the clinical management of lung cancer. The role of nanobioengineered (bio-nano) tools like bio-nanocarriers and nanobiodevices in secondary prophylaxis, diagnosis, therapeutics, and theranostics for lung cancer management has been discussed. Bioengineered, bioinspired, and biomimetic bio-nanotools of considerate translational value have been reviewed. Perspectives on existent oncostrategies, their critical comparison with bio-nanocarriers, and issues hampering their clinical bench side to bed transformation have also been summarized.

Dual-Ligand-Modified Liposomes Co-Loaded with Anti-Angiogenic and Chemotherapeutic Drugs for Inhibiting Tumor Angiogenesis and Metastasis

BACKGROUND

Tumor angiogenesis has been proven to potentiate tumor growth and metastasis; therefore, the strategies targeting tumor-related angiogenesis have great potentials in antitumor therapy.

METHODS

Here, the GA&Gal dual-ligand-modified liposomes co-loaded with curcumin and combretastatin A-4 phosphate (CUCA/GA&Gal-Lip) were prepared and characterized. A novel "BEL-7402+HUVEC" co-cultured cell model was established to mimic tumor microenvironment. The cytotoxicity and migration assays were performed against the novel co-cultured model. Angiogenesis ability was evaluated by tube formation test, and in vivo metastatic ability was evaluated by lung metastasis test.

RESULTS

The result demonstrated that dual-ligand-modified liposomes showed greater inhibition of tumor angiogenesis and metastasis in comparison with other combined groups. Significantly, the mechanism analysis revealed that curcumin and combretastatin A-4 phosphate could inhibit tumor angiogenesis and metastasis via down-regulation of VEGF and VEGFR2 expression, respectively, and that GA&Gal-Lip could improve antitumor effect by GA/Gal-mediated active-targeting delivery.

CONCLUSION

CUCA/GA&Gal-Lip hold great potentials in hepatoma-targeting delivery of antitumor drugs and can achieve anti-angiogenic and anti-metastatic effects by simultaneously blocking VEGF/VEGFR2 signal pathway, therefore exhibiting superior anti-hepatoma efficacy.

Nanomedicine-based strategies to target and modulate the tumor microenvironment

The interest in nanomedicine for cancer theranostics has grown significantly over the past few decades. However, these nanomedicines need to overcome several physiological barriers intrinsic to the tumor microenvironment (TME) before reaching their target. Intrinsic tumor genetic/phenotypic variations, along with intratumor heterogeneity, provide different cues to each cancer type, making each patient with cancer unique. This brings additional challenges in translating nanotechnology-based systems into clinically reliable therapies. To develop efficient therapeutic strategies, it is important to understand the dynamic interactions between TME players and the complex mechanisms involved, because they constitute invaluable targets to dismantle tumor progression. In this review, we discuss the latest nanotechnology-based strategies for cancer diagnosis and therapy as well as the potential targets for the design of future anticancer nanomedicines.

Recent progress on charge-reversal polymeric nanocarriers for cancer treatments

Nanocarriers (NCs) for delivery anticancer therapeutics have been under development for decades. Although great progress has been achieved, the clinic translation is still in the infancy. The key challenge lies in the biological barriers which lie between the NCs and the target spots, including blood circulation, tumor penetration, cellular uptake, endo-/lysosomal escape, intracellular therapeutics release and organelle targeting. Each barrier has its own distinctive microenvironment and requires different surface charge. To address this challenge, charge-reversal polymeric NCs have been a hot topic, which are capable of overcoming each delivery barrier, by reversing their charges in response to certain biological stimuli in the tumor microenvironment. In this review, the triggering mechanisms of charge reversal, including pH, enzyme and redox approaches are summarized. Then the corresponding design principles of charge-reversal NCs for each delivery barrier are discussed. More importantly, the limitations and future prospects of charge-reversal NCs in clinical applications are proposed.

Biodistribution of etoposide via intratumoral chemotherapy with etoposide-loaded implants

Etoposide (VP16) is the traditional antitumor agent which has been widely used in a variety of cancers. However, intravenous administration of VP16 was limited in clinical application because of its low aqueous solubility, poor bioavailability and dose-limiting adverse effects. Local chemotherapy with VP16-loaded drug delivery systems could provide a continuous release of drug at the target site, while minimizing the systemic toxicity. In this study, we prepared the poly-l-lactic acid (PLLA) based VP16-loaded implants (VP16 implants) by the direct compression method. The VP16 implants were characterized with regards to drug content, micromorphology, drug release profiles, differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) analyses. Furthermore, the biodistribution of VP16 via intratumoral chemotherapy with VP16 implants was investigated using the murine Lewis lung carcinoma model. Our results showed that VP16 dispersed homogenously in the polymeric matrix. Both in vitro and in vivo drug release profiles of the implants were characterized by high initial burst release followed by sustained release of VP16. The VP16 implants showed good compatibility between VP16 and the excipients. Intratumoral chemotherapy with VP16 implants resulted in significantly higher concentration and longer duration of VP16 in tumor tissues compared with single intraperitoneal injection of VP16 solution. Moreover, we found the low level of VP16 in plasma and normal organ tissues. These results suggested that intratumoral chemotherapy with VP16 implants enabled high drug concentration at the target site and has the potential to be used as a novel method to treat cancer.

Salvianolic acid A blocks vasculogenic mimicry formation in human non-small cell lung cancer via PI3K/Akt/mTOR signalling

Vasculogenic mimicry (VM) is associated with aggressive cancer cells. Salvianolic acid A (Sal-A), an antioxidant and anti-inflammatory agent, has bioactive properties from Salvia miltiorrhiza Bunge. Current investigation aspired to explore the activity of Sal-A in the VM formation of non-small cell lung cancer (NSCLC) and the mechanism underling this function. The CCK8, the scratch and boyden chemotaxis assay were presented to describe NSCLC cells viability, migration and invasion capabilities, respectively. The protein expression was verified by western blotting. In this report, Sal-A caused a reduction in viability, metastasis and capillaries structure formation of NSCLC cells. Additionally, Sal-A markedly prevented the key VM related proteins, containing EphA2, VE-cadherin and MMP2. Besides, Sal-A significantly diminished p-PI3K, p-Akt and p-mTOR level in NSCLC cells. More importantly, SC79 pretreatment reversed Sal-A inhibits NSCLC cells viability, metastasis and VM formation. These data exhibit that Sal-A could block VM network formation in NSCLC cells through modulating the PI3K/Akt/mTOR signalling pathway.

Delivery of cancer therapies by synthetic and bio-inspired nanovectors

BACKGROUND

As a complement to the clinical development of new anticancer molecules, innovations in therapeutic vectorization aim at solving issues related to tumor specificity and associated toxicities. Nanomedicine is a rapidly evolving field that offers various solutions to increase clinical efficacy and safety. MAIN: Here are presented the recent advances for different types of nanovectors of chemical and biological nature, to identify the best suited for translational research projects. These nanovectors include different types of chemically engineered nanoparticles that now come in many different flavors of 'smart' drug delivery systems. Alternatives with enhanced biocompatibility and a better adaptability to new types of therapeutic molecules are the cell-derived extracellular vesicles and micro-organism-derived oncolytic viruses, virus-like particles and bacterial minicells. In the first part of the review, we describe their main physical, chemical and biological properties and their potential for personalized modifications. The second part focuses on presenting the recent literature on the use of the different families of nanovectors to deliver anticancer molecules for chemotherapy, radiotherapy, nucleic acid-based therapy, modulation of the tumor microenvironment and immunotherapy.

CONCLUSION

This review will help the readers to better appreciate the complexity of available nanovectors and to identify the most fitting "type" for efficient and specific delivery of diverse anticancer therapies.