Tumor-targeted delivery of copper-manganese biomineralized oncolytic adenovirus for colorectal cancer immunotherapy.

Oncolytic viral therapy (OVT) is a novel anti-tumor immunotherapy approach, specifically replicating within tumor cells. Currently, oncolytic viruses are mainly administered by intratumoral injection. However, achieving good results for distant metastatic tumors is challenging. In this study, a multifunctional oncolytic adenovirus, OA@CuMnCs, was developed using bimetallic ions copper and manganese. These metal cations form a biomineralized coating on the virus's surface, reducing immune clearance. It is known that viruses upregulate the expression of PD-L1. Copper ions in OA@CuMnCs can decrease the PD-L1 expression of tumor cells, thereby promoting immune cell-related factor release. This process involves antigen presentation and the combination of immature dendritic cells, transforming them into mature dendritic cells. It changes "cold" tumors into "hot" tumors, further inducing immunogenic cell death. While oncolytic virus replication requires oxygen, manganese ions in OA@CuMnCs can react with endogenous hydrogen peroxide. This reaction produces oxygen, enhancing the virus's replication ability and the tumor lysis effect. Thus, this multifunctionally coated OA@CuMnCs demonstrates potent amplification in immunotherapy efficacy, and shows great potential for further clinical OVT. STATEMENT OF SIGNIFICANCE: Oncolytic virus therapy (OVs) is a new anti-tumor immunotherapy method that can specifically replicate in tumor cells. Although the oncolytic virus can achieve a therapeutic effect on some non-metastatic tumors through direct intratumoral injection, there are still three major defects in the treatment of metastatic tumors: immune response, hypoxia effect, and administration route. Various studies have shown that the immune response in vivo can be overcome by modifying or wrapping the surface protein of the oncolytic virus. In this paper, a multifunctional coating of copper and manganese was prepared by combining the advantages of copper and manganese ions. The coating has a simple preparation method and mild conditions, and can effectively enhance tumor immunotherapy.

Engineered Luminescent Oncolytic Vaccinia Virus Activation of Photodynamic-Immune Combination Therapy for Colorectal Cancer.

Oncolytic virus therapy is currently regarded as a promising approach in cancer immunotherapy. It has greater therapeutic advantages for colorectal cancer that is prone to distant metastasis. However, the therapeutic efficacy and clinical application of viral agents alone for colorectal cancer remain suboptimal. In this study, an engineered oncolytic vaccinia virus (OVV-Luc) that expresses the firefly luciferase gene is developed and loaded Chlorin e6 (Ce6) onto the virus surface through covalent coupling, resulting in OVV-Luc@Ce6 (OV@C). The OV@C infiltrates tumor tissue and induces endogenous luminescence through substrate catalysis, resulting in the production of reactive oxygen species. This unique system eliminates the need for an external light source, making it suitable for photodynamic therapy (PDT) in deep tissues. Moreover, this synergistic effect between PDT and viral immunotherapy enhances dendritic cell maturation, macrophage polarization, and reversal of the immunosuppressive microenvironment. This synergistic effect has the potential to convert a "cold" into a "hot" tumor, it offers valuable insights for clinical translation and application.

Crosstalk between oncolytic viruses and autophagy in cancer therapy.

Oncolytic viruses have attracted attention as a promising strategy in cancer therapy owing to their ability to selectively infect and kill tumor cells, without affecting healthy cells. They also exert their anti-tumor effects by releasing immunostimulatory molecules from dying cancer cells. Several regulatory mechanisms, such as autophagy, contribute to the anti-tumor properties of oncolytic viruses. Autophagy is a conserved catabolic process in responses to various stresses, such as nutrient deprivation, hypoxia, and infection that produces energy by lysosomal degradation of intracellular contents. Autophagy can support infectivity and replication of the oncolytic virus and enhance their anti-tumor effects via mediating oncolysis, autophagic cell death, and immunogenic cell death. On the other hand, autophagy can reduce the cytotoxicity of oncolytic viruses by providing survival nutrients for tumor cells. In his review, we summarize various types of oncolytic viruses in clinical trials, their mechanism of action, and autophagy machinery. Furthermore, we precisely discuss the interaction between oncolytic viruses and autophagy in cancer therapy and their combinational effects on tumor cells.

Delivery systems for enhancing oncolytic adenoviruses efficacy.

Oncolytic adenovirus (OAds) has long been considered a promising biotherapeutic agent against various types of cancer owing to selectively replicate in and lyse cancer cells, while remaining dormant in healthy cells. In the last years, multiple (pre)clinical studies using genetic engineering technologies enhanced OAds anti-tumor effects in a broad range of cancers. However, poor targeting delivery, tropism toward healthy tissues, low-level expression of Ad receptors on tumor cells, and pre-existing neutralizing antibodies are major hurdles for systemic administration of OAds. Different vehicles have been developed for addressing these obstacles, such as stem cells, nanoparticles (NPs) and shielding polymers, extracellular vesicles (EVs), hydrogels, and microparticles (MPs). These carriers can enhance the therapeutic efficacy of OVs through enhancing transfection, circulatory longevity, cellular interactions, specific targeting, and immune responses against cancer. In this paper, we reviewed adenovirus structure and biology, different types of OAds, and the efficacy of different carriers in systemic administration of OAds.

Membrane Derived Vesicles as Biomimetic Carriers for Targeted Drug Delivery System.

Extracellular vesicles (EVs) are membrane vesicles (MVs) playing important roles in various cellular and molecular functions in cell-to-cell signaling and transmitting molecular signals to adjacent as well as distant cells. The preserved cell membrane characteristics in MVs derived from live cells, give them great potential in biological applications. EVs are nanoscale particulates secreted from living cells and play crucial roles in several important cellular functions both in physiological and pathological states. EVs are the main elements in intercellular communication in which they serve as carriers for various endogenous cargo molecules, such as RNAs, proteins, carbohydrates, and lipids. High tissue tropism capacity that can be conveniently mediated by surface molecules, such as integrins and glycans, is a unique feature of EVs that makes them interesting candidates for targeted drug delivery systems. The cell-derived giant MVs have been exploited as vehicles for delivery of various anticancer agents and imaging probes and for implementing combinational phototherapy for targeted cancer treatment. Giant MVs can efficiently encapsulate therapeutic drugs and deliver them to target cells through the membrane fusion process to synergize photodynamic/photothermal treatment under light exposure. EVs can load diagnostic or therapeutic agents using different encapsulation or conjugation methods. Moreover, to prolong the blood circulation and enhance the targeting of the loaded agents, a variety of modification strategies can be exploited. This paper reviews the EVs-based drug delivery strategies in cancer therapy. Biological, pharmacokinetics and physicochemical characteristics, isolation techniques, engineering, and drug loading strategies of EVs are discussed. The recent preclinical and clinical progresses in applications of EVs and oncolytic virus therapy based on EVs, the clinical challenges and perspectives are discussed.

The limiting factors of oncolytic virus immunotherapy and the approaches to overcome them.

Oncolytic virus (OV) immunotherapy is characterized by viruses which specifically target cancer cells and cause their cytolysis. They provide a unique and promising new tool for the eradication of cancer as they interact with and affect the tumor microenvironment (TME), vasculature, and immune system. Advancements of genetic engineering have allowed for these viruses to be armed in such a way to have enhanced targeting, strong immunomodulation properties, and an ability to modify the TME. However, there are still major limitations in their use, mostly due to difficulties in delivering the viral particles to the tumors and in ensuring that the immunomodulatory properties are able to stimulate the host immune response to mount a complete response. Using novel delivery systems and using OVs as a complementary therapy in a combinatorial treatment have shown some significant successes. In this review, we discuss the major issues and difficulties in using OVs as anti-tumor agents and some of the strategies put in place so far to overcome these limitations. KEY POINTS: • Oncolytic viruses (OVs) infect cancer cells and cause their cytolysis. • The major limitations in using OVs as anti-tumor therapy were discussed. • The potential strategies to overcome these limitations were summarized.

Association between the methylation status of PCDH17 and the efficacy of neoadjuvant chemotherapy in triple-negative breast cancer.

The present study aimed to assess whether the methylation status of the protocadherin 17 gene (PCDH17) in triple-negative breast cancer (TNBC) tissues was associated with the efficacy of neoadjuvant chemotherapy (NAC). The present study included 280 patients diagnosed with TNBC using core needle biopsy. Tumor pathological diagnosis was determined via hematoxylin and eosin staining. Immunohistochemical staining was used to determine estrogen receptor, progesterone receptor, human epidermal growth factor receptor-2 and Ki-67 status. PCDH17 methylation status was analyzed using methylation-specific PCR. χ2 tests were performed to analyze differences between PCDH17 methylation status and TNBC clinicopathological features. Univariate and multivariate logistic regressions were used to analyze whether PCDH17 methylation status predicted a curative effect of NAC. The multivariate analysis included factors with P<0.2 from the univariate analysis and those that were clinically associated with NAC. A total of 228 patients were positive for PCDH17 methylation, while the remainder 52 were negative. Additionally, 107 patients achieved pathological complete response (pCR) after NAC. The pCR rate was 67.3% among the 52 patients negative for PCDH17 methylation and 31.6% among the 228 patients positive for PCDH17 methylation. Patients who were negative for PCDH17 methylation and had high Ki67 expression exhibited significantly higher pCR rates than their counterparts. The present results demonstrate that PCDH17 methylation status may predict the response to NAC in patients with TNBC. Therefore, this epigenetic characteristic may serve as an indicator of treatment efficacy.

Nanotechnology Assisted Chemotherapy for Targeted Cancer Treatment: Recent Advances and Clinical Perspectives.

Nanotechnology has recently provided exciting platforms in the field of anticancer research with promising potentials for improving drug delivery efficacy and treatment outcomes. Nanoparticles (NPs) possess different advantages over the micro and bulk therapeutic agents, including their capability to carry high payloads of drugs, with prolonged half-life, reduced toxicity of the drugs, and increased targeting efficiency. The wide variety of nanovectors, coupled with different conjugation and encapsulation methods available for different theranostic agents provide promising opportunities to fine-tune the pharmacological properties of these agents for more effective cancer treatment methods. This review discusses applications of NPs-assisted chemotherapy in preclinical and clinical settings and recent advances in design and synthesis of different nanocarriers for chemotherapeutic agents. Moreover, physicochemical properties of different nanocarriers, their impacts on different tumor targeting strategies and effective parameters for efficient targeted drug delivery are discussed. Finally, the current approved NPs-assisted chemotherapeutic agents for clinical applications and under different phases of clinical trials are discussed.

Recent advances in targeting cancer stem cells using oncolytic viruses.

Oncolytic virotherapy is a promising antitumor strategy which utilizes the lytic nature of viral replication to kill cancer cells. Oncolytic viruses (OVs) can induce cancer cell death and trigger immune responses to metastatic cancer in vivo. Reverse genetic systems have aided the insertion of anticancer genes into various OVs to augment their oncolytic capacity. Furthermore, OVs target and destroy the population of tumor-initiating cancer stem cells. These cancer stem cells are associated with metastasis and development of resistance to conventional anticancer approaches. Targeting cancer stem cells is essential since killing only differentiated tumor cells may lead to enrichment of cancer stem cells and thus indicate a poor prognosis. In this review, we summarize the oncolytic activity of various classes of OVs towards different types of cancer stem cells and also discuss the synergistic activity achieved by the combination of OVs with traditional therapies on chemo- and radiotherapy-resistant cancer stem cells.

Immune-mediated adverse effects of immune-checkpoint inhibitors and their management in cancer.

Within the past decade, immune-checkpoint inhibitors (ICPIs), including anti-programmed cell death 1 (PD-1), anti-programmed cell death 1 ligand 1 (PD-L1), and anti-cytotoxic T lymphocyte antigen 4 (CTLA-4) antibodies, are undoubtfully the most remarkable advances in cancer therapy. The immune responses are modulated by these ICPIs via blocking the inhibitory PD-1/PD-L1 path and result in immune activation in the suppressive microenvironment of the tumor. While ICPIs result in benefits for numerous patients with malignancy and lead to disease control and survival, toxicity and safety problems have emerged as well. Although immune mediated adverse effects due to ICPIs could involve any organ system, skin, endocrine glands, and gastrointestinal tract, are one of the most commonly affected. Fortunately, in most of the cases, these immune­mediated adverse effects (imAEs) are manageable, while in some cases these toxicities are fulminant and fatal and lead to the withdrawal of treatment. Numerous attempts have been started and are continuing to reduce the incidence rate of imAEs. Further studies are required for a better understanding of these imAEs, decrease the occurrence, and lighten the severity. In this work, we overview the imAEs and also, highlight the most important aspects of the imAEs management.

Current progress in the clinical use of circulating tumor cells as prognostic biomarkers.

The process of metastasis is characterized by the shedding of tumor cells into the bloodstream, where they are transported to other parts of the body to seed new tumors. These cells, known as circulating tumor cells (CTCs), have the potential to reveal much about an individual cancer case, and theoretically can aid in the prediction of outcomes and design of precision treatments. Recent advances in technology now allow for the robust and reproducible characterization of CTCs from a simple blood draw. Both the number of circulating cells and important molecular characteristics correlated with clinical phenotypes such as drug resistance can be obtained and used for real-time prognostic analysis. Molecular characterization can provide a snapshot of the activity of the main tumor (serving as a "liquid biopsy") and early warnings concerning changes such as the development of resistance, and aid in predicting the efficacy of different therapeutic approaches for treatment optimization. Herein, the authors review the current clinical use of CTCs as prognostic biomarkers for several different cancers. The quantification of CTCs can lead to more accurate staging and decision making regarding options such as adjuvant chemotherapy.

Hydroxychloroquine potentiates the anti-cancer effect of bevacizumab on glioblastoma via the inhibition of autophagy.

Bevacizumab (BEV) is widely used for the treatment of patients with recurrent glioblastoma (GBM), but recent evidence demonstrated that BEV induced cytoprotective autophagy, which allows tumor cells to survive. Hydroxychloroquine (HCQ) inhibits lysosomal acidification and blocks autophagy via influencing autophagosome fusion and degradation. HCQ is often used to enhance the efficacy of chemoradiotherapy. However, whether HCQ sensitizes GBM cells to BEV and the molecular mechanism of this effect are not clear. We showed that high concentrations of BEV increased the LC3-II/LC3-I ratio and caused the degradation of Beclin1 in the LN18 and LN229 cell lines, indicating that high concentrations of BEV induced the autophagy of the LN18 and LN229 cells. However, BEV (100 µg/ml) did not influence the autophagy of the LN18 and LN229 cells, and HCQ at less than 5 µg/ml significantly accumulated LC3B-II and p62 proteins and blocked the autophagy process. Importantly, we found that HCQ (5 µg/ml) potentiated the anti-cancer effect of BEV (100 µg/ml). Therefore, HCQ is a novel strategy that may augment the efficacy of BEV for GBM via the inhibition of autophagy.

Recent advances in oncolytic virus-based cancer therapy.

Administration of oncolytic viruses (OVs) is an emerging anticancer strategy that exploits the lytic nature of viral replication to enhance the killing of malignant cells. OVs can be used as tools to directly induce cancer cell death and to trigger local and/or systemic immune responses to metastatic cancer in vivo. The effectiveness of OV therapy was initially highlighted by the clinical use of the genetically modified herpes virus, talimogene laherparepvec, for melanoma therapy. A number of OVs are now being evaluated as potential treatments for cancer in clinical trials. In spite of being engineered to specifically target tumor cells, the safety and off-target effects of OV therapy are a concern. The potential safety concerns of OVs are highlighted by current clinical trial criteria, which exclude individuals harbouring other viral infections and people who are immunocompromised. Despite the potential for adverse effects, clinical trials to date revealed relatively minimal adverse immune-related effects, such as fever. With advances in our understanding of virus replication cycles, several novel OVs have emerged. Reverse genetic systems have facilitated the insertion of anticancer genes into a range of OVs to further enhance their tumor-killing capacity. In this review, we highlight the recent advances in OV therapy for a range of human cancers in in vitro and in in vivo animal studies. We further discuss the future of OVs as a therapeutic strategy for a range of life-threatening cancers.

[Research advances in endogenous neural stem cells promoting neural repair after ischemic stroke].

Neural stem cell therapy, as a new therapeutic method for neural diseases, has aroused a wide concern for over 20 years since neural stem cells were first found in 1992. Ischemic stroke is highly concerned because of its high incidence, mortality and disability rates. Because the brain has a limited ability to repair itself, to improve neural function and promote neural regeneration may help to prevent occurrence and development of neurological diseases. It is noteworthy that some stroke patients showed an ability to repair brain several months after the stroke happened, suggesting an existence of endogenous nerve repair in these patients. The research advances in functions of endogenous neural stem cells in neural regeneration and the related regulators after ischemic stroke are summarized in this review to provide new views of the mechanism of neural functional recovery after ischemic stroke.

Recent advances in carbohydrate-based cancer vaccines.

Cancer is a complex multifactorial disease for which many promising therapeutic strategies such as immunotherapy are emerging. Malignant cells frequently express aberrant cell surface carbohydrates, which differentiate them from normal "healthy" cells. This characteristic presents a window for the development of synthetic carbohydrate antigen-based cancer vaccines which can be recognized by the immune system and can bring about T cell-dependent immune responses. Antibodies generated against the carbohydrate antigens partake in the inactivation of carbohydrate-decorated cancer cells, by slowing down tumor cell growth and inducing cancer cell apoptosis. Novel synthetic strategies for carbohydrate antigens have led to several synthetic cancer vaccine candidates. In the present review, we describe the latest progress in carbohydrate-based cancer vaccines and their clinical evaluation in various cancers.

Ceramide-Graphene Oxide Nanoparticles Enhance Cytotoxicity and Decrease HCC Xenograft Development: A Novel Approach for Targeted Cancer Therapy.

Despite substantial efforts to develop novel therapeutic strategies for treating hepatocellular carcinoma (HCC), the effectiveness and specificity of available drugs still require further improvement. Previous work has shown that exogenous ceramide can play a key role in inducing the apoptotic death of cancer cells, however, the poor water-solubility of this compound has hampered its use for cancer treatment. In the present study, we used polyethylene glycol (PEG) and polyethylenimine (PEI) co-conjugated ultra-small nano-GO (NGO-PEG-PEI) loaded with C6-ceramide (NGO-PEG-PEI/Cer) as a strategy for HCC treatment. We assessed the biological role of NGO-PEG-PEI/Cer, and we assessed its antitumor efficacy against HCC both in vitro and in vivo in combination with the chemotherapeutic drug sorafenib. We found that NGO-PEG-PEI significantly enhanced the cellular uptake of C6-ceramide. By investigating the mechanism of cellular delivery, we determined that the internalization of NGO-PEG-PEI/Cer progressed primarily via a clathrin-mediated mechanism. The combination of NGO-PEG-PEI/Cer and sorafenib exhibited synergy between these two drugs. Further work revealed that NGO-PEG-PEI/Cer may play a role in subverting multidrug resistance (MDR) in HCC cells by inactivating MDR and Akt signaling. NGO-PEG-PEI/Cer also significantly inhibited tumor growth and improved survival times in vivo, and the synergetic effect of NGO-PEG-PEI/Cer combined with sorafenib was also observed in drug-resistant HCC xenografts. In conclusion, our NGO-PEG-PEI nanocomposite is an effective nano-platform for loading C6-ceramide for therapeutic use in treating HCC, exhibiting high cancer cell killing potency in this tumor model. The NGO-PEG-PEI/Cer/sorafenib combination additionally represents a promising potential therapeutic strategy for the treatment of drug-resistant HCC.

Decreased CRHBP expression is predictive of poor prognosis in patients with hepatocellular carcinoma.

Corticotropin releasing hormone binding protein (CRHBP) mediates the reaction between corticotropin releasing hormone (CRH) and corticotropin releasing hormone receptors (CRHRs). It is expressed in a number of organs, and the expression of CRHBP is associated with tumorigenesis and cancer progression. The aim of the present study was to investigate CRHBP expression levels in hepatocellular carcinoma (HCC) and its association with patient clinicopathological characteristics as well as prognosis. The expression of CRHBP was examined by immunohistochemistry in 169 HCC tissues and 151 adjacent non-tumorous tissues. The results were validated by western blotting using patient tissues and liver cancer cell lines. The association of CRHBP expression with clinicopathological patient characteristics and survival rate was analyzed statistically. Expression of CRHBP was detected in 142/151 (94.0%) non-tumorous liver tissues, and 84/169 (49.7%) HCC tissues (P<0.001). The expression of CRHBP was negatively associated with tumor size (P=0.013), Edmondson Grade (P=0.002), hepatitis B virus antigen (P=0.020), and α-fetoprotein levels (P=0.014). Patients exhibiting low CRHBP expression were associated with shorter survival time compared with those exhibiting high CRHBP expression (P=0.012). The results of western blotting analysis suggest that reduced CRHBP expression is frequently observable in patients with HCC. Low CRHBP expression in HCC tissues may be a predictor of clinical prognosis and a potential therapeutic target for HCC.

The correlation of NLRC3 expression with the progression and prognosis of hepatocellular carcinoma.

NLRC3 is a member of the nucleotide-binding domain and leucine-rich repeat (NLR) family protein that plays a role in inflammation and immunity. Although chronic inflammation has been identified as a hallmark of cancer, NLRC3 expression correlation with the development and prognosis of hepatocellular carcinoma (HCC) is unclear. In the present study, we first used Oncomine and OncoLnc database to determine the clinical significance of NLRC3 in HCC. Then we performed quantitative real-time polymerase chain reaction, Western blot, and immunohistochemical staining (IHC) and analyzed the correlation between NLRC3 expression and clinicopathological features of HCC in a Chinese population. We found that high levels of NLRC3 messenger RNA (mRNA) correlated with a favorable clinical outcome; furthermore, expression of NLRC3 was significantly reduced in the cancer tissue in patients compared with noncancerous hepatic tissues. NLRC3 reduction was correlated with Edmondson grade and metastasis. Kaplan-Meier survival analysis revealed that HCC patients with high expression of NLRC3 have a more favorable prognosis compared with those with low expression of NLRC3. We then used short hairpin RNA to knock down NLRC3 expression in HCC cell lines and evaluated its effect on cell proliferation and apoptosis. Suppression of NLRC3 expression promoted cell proliferation and inhibited apoptosis in vitro. Genomic analysis of the OncoLnc database also showed that NLRC3 mRNA level was directly correlated with mRNA levels of inflammasome components caspase-1, IL-1ß, and IL-18. Based on our present study, down-regulated expression of NLRC3 may play an important role in cancer progression and prognosis of HCC by acting as a tumor suppressor.

Ovatodiolide targets chronic myeloid leukemia stem cells by epigenetically upregulating hsa-miR-155, suppressing the BCR-ABL fusion gene and dysregulating the PI3K/AKT/mTOR pathway.

Chronic myeloid leukemia (CML) is a myeloproliferative pathology, originating from the hematopoietic cancer stem cells (hCSCs) due to the Bcl-Abl Philadelphia chromosome transformation. However, targeting these hCSCs as an effective anti-CML strategy is relatively less explored. Ovatodiolide (Ova) is a natural diterpenoid isolate of Anisomeles indica with broad anticancer activity. In this study, we investigated the anti-hCSCs potential of Ova against CD34+/CD38-, CD34+/CD38+, and unsorted K562 cell lines using flow cytometry, western blot, RT-PCR, genomic mapping, and tumorsphere formation assays. We demonstrated that compared to unsorted K562 and CD34+/CD38+, CD34+/CD38- cells were significantly enriched with Oct4, Sox2, CD133, Bcr-Abl, p-CrkL and p-Stat5 protein and/or mRNA. Furthermore, we showed that Ova alone or by enhancing the therapeutic potential of Imatinib, reduced the viability of CML cell lines, dose-dependently, irrespective of the cancer stemness, as well as markedly inhibit the Bcr-Abl, p-CrkL, Stat5, and MDR protein expression levels in CD34+ cells. Mechanistic investigations revealed a significant up-regulation of hsa-miR-155, which resulted in the reduction of dysregulating the PIK3CA expression in Ova-treated K562 CD34+/CD38- cells. Additionally, Ova alone or in combination with Imatinib suppressed the hCSC traits of the CD34+/CD38- cells, resulting in loss of their ability to form tumorspheres, enhanced apoptosis, increase in the Bax/Bcl-2 ratio, and dysregulation of the PI3K/AKT/mTOR signaling pathway. Together, these results demonstrate the PI3K/AKT/mTOR signaling-mediated anti-hCSC effect of Ova in CML, as well as suggest a likely role for Ova as a small molecule PI3K/mTOR dual inhibitor, thus, extending its potential benefit to other mTOR-mediated pathologies.