Anti-angiogenic treatment (Bevacizumab) improves the responsiveness of photodynamic therapy in colorectal cancer

Molecular Determinants for Photodynamic Therapy Resistance and Improved Photosensitizer Delivery in Glioma

Gliomas account for 24% of all the primary brain and Central Nervous System (CNS) tumors. These tumors are diverse in cellular origin, genetic profile, and morphology but collectively have one of the most dismal prognoses of all cancers. Work is constantly underway to discover a new effective form of glioma therapy. Photodynamic therapy (PDT) may be one of them. It involves the local or systemic application of a photosensitive compound-a photosensitizer (PS)-which accumulates in the affected tissues. Photosensitizer molecules absorb light of the appropriate wavelength, initiating the activation processes leading to the formation of reactive oxygen species and the selective destruction of inappropriate cells. Research focusing on the effective use of PDT in glioma therapy is already underway with promising results. In our work, we provide detailed insights into the molecular changes in glioma after photodynamic therapy. We describe a number of molecules that may contribute to the resistance of glioma cells to PDT, such as the adenosine triphosphate (ATP)-binding cassette efflux transporter G2, glutathione, ferrochelatase, heme oxygenase, and hypoxia-inducible factor 1. We identify molecular targets that can be used to improve the photosensitizer delivery to glioma cells, such as the epithelial growth factor receptor, neuropilin-1, low-density lipoprotein receptor, and neuropeptide Y receptors. We note that PDT can increase the expression of some molecules that reduce the effectiveness of therapy, such as Vascular endothelial growth factor (VEGF), glutamate, and nitric oxide. However, the scientific literature lacks clear data on the effects of PDT on many of the molecules described, and the available reports are often contradictory. In our work, we highlight the gaps in this knowledge and point to directions for further research that may enhance the efficacy of PDT in the treatment of glioma.

Neuropilin-1-Targeted Nanomedicine for Spatiotemporal Tumor Suppression through Photodynamic Vascular Damage and Antiangiogenesis

Antiangiogenic therapy is an effective way to disrupt nutrient supply and starve tumors, but it is restricted by poor efficacy and negative feedback-induced tumor relapse. In this study, a neuropilin-1 (NRP-1)-targeted nanomedicine (designated as FPPT@Axi) is reported for spatiotemporal tumor suppression by combining photodynamic therapy (PDT) with antiangiogenesis. In brief, FPPT@Axi is prepared by utilizing an NRP-1-targeting chimeric peptide (Fmoc-K(PpIX)-PEG8-TKPRR) to encapsulate the antiangiogenic drug Axitinib (Axi). Importantly, the NRP-1-mediated targeting property enables FPPT@Axi to selectively concentrate at vascular endothelial and breast cancer cells, facilitating the production of reactive oxygen species (ROS) in situ for specific vascular disruption and enhanced cell apoptosis under light stimulation. Moreover, the codelivered Axi can further inhibit vascular endothelial growth factor receptor (VEGFR) to impair the negative feedback of PDT-induced tumor neovascularization. Consequently, FPPT@Axi spatiotemporally restrains the tumor growth through blocking angiogenesis, destroying tumor vessels, and inducing tumor apoptosis. Such an NRP-1-mediated targeting codelivery system sheds light on constructing an appealing candidate with translational potential by using clinically approved PDT and chemotherapy.

Photodynamic Therapy and Immunological View in Gastrointestinal Tumors

Gastrointestinal cancers are a specific group of oncological diseases in which the location and nature of growth are of key importance for clinical symptoms and prognosis. At the same time, as research shows, they pose a serious threat to a patient's life, especially at an advanced stage of development. The type of therapy used depends on the anatomical location of the cancer, its type, and the degree of progression. One of the modern forms of therapy used to treat gastrointestinal cancers is PDT, which has been approved for the treatment of esophageal cancer in the United States. Despite the increasingly rapid clinical use of this treatment method, the exact immunological mechanisms it induces in cancer cells has not yet been fully elucidated. This article presents a review of the current understanding of the mode of action of photodynamic therapy on cells of various gastrointestinal cancers with an emphasis on colorectal cancer. The types of cell death induced by PDT include apoptosis, necrosis, and pyroptosis. Anticancer effects are also a result of the destruction of tumor vasculature and activation of the immune system. Many reports exist that concern the mechanism of apoptosis induction, of which the mitochondrial pathway is most often emphasized. Photodynamic therapy may also have a beneficial effect on such aspects of cancer as the ability to develop metastases or contribute to reducing resistance to known pharmacological agents.

Photodynamic Therapy for Colorectal Cancer: An Update and a Look to the Future

This review provides an update on the current state of photodynamic therapy (PDT) for colorectal cancer (CRC) and explores potential future directions in this field. PDT has emerged as a promising minimally invasive treatment modality that utilizes photosensitizers and specific light wavelengths to induce cell death in targeted tumor tissues. In recent years, significant progress has been made in understanding the underlying mechanisms, optimizing treatment protocols, and improving the efficacy of PDT for CRC. This article highlights key advancements in PDT techniques, including novel photosensitizers, light sources, and delivery methods. Furthermore, it discusses ongoing research efforts and potential future directions, such as combination therapies and nanotechnology-based approaches. By elucidating the current landscape and providing insights into future directions, this review aims to guide researchers and clinicians in harnessing the full potential of PDT for the effective management of CRC.

Nanomaterial-Based Antivascular Therapy in the Multimodal Treatment of Cancer

Abnormal tumor vasculature and a hypoxic tumor microenvironment (TME) limit the effectiveness of conventional cancer treatment. Recent studies have shown that antivascular strategies that focus on antagonizing the hypoxic TME and promoting vessel normalization effectively synergize to increase the antitumor efficacy of conventional therapeutic regimens. By integrating multiple therapeutic agents, well-designed nanomaterials exhibit great advantages in achieving higher drug delivery efficiency and can be used as multimodal therapy with reduced systemic toxicity. In this review, strategies for the nanomaterial-based administration of antivascular therapy combined with other common tumor treatments, including immunotherapy, chemotherapy, phototherapy, radiotherapy, and interventional therapy, are summarized. In particular, the administration of intravascular therapy and other therapies with the use of versatile nanodrugs is also described. This review provides a reference for the development of multifunctional nanotheranostic platforms for effective antivascular therapy in combined anticancer treatments.

The ALK1‑Smad1/5‑ID1 pathway participates in tumour angiogenesis induced by low‑dose photodynamic therapy

Photodynamic therapy (PDT) is an effective and low‑invasive tumour therapy. However, it can induce tumour angiogenesis, which is a main factor leading to tumour recurrence and metastasis. Activin receptor‑like kinase‑1 (ALK1) is a key factor regulating angiogenesis. However, it remains unclear whether ALK1 plays an unusual role in low‑dose PDT‑induced tumour angiogenesis. In the present study, human umbilical vein endothelial cells (HUVECs) co‑cultured with breast cancer MDA‑MB‑231 cells (termed HU‑231 cells) were used to construct an experimental model of tumour angiogenesis induced by low‑dose PDT. The viability, and the proliferative, invasive, migratory, as well as the tube‑forming ability of the HU‑231 cells were evaluated following low‑dose PDT. In particular, ALK1 inhibitor and and an adenovirus against ALK1 were used to further verify the role of ALK1 in low‑dose PDT‑induced tumour angiogenesis. Moreover, the expression of ALK1, inhibitor of DNA binding 1 (ID1), Smad 1, p‑Smad1/5, AKT and PI3K were detected in order to verify the underlying mechanisms. The findings indicated that low‑dose PDT enhanced the proliferative ability of the HU‑231 cells and reinforced their migratory, invasive and tube formation capacity. However, these effects were reversed with the addition of an ALK1 inhibitor or by the knockdown of ALK1 using adenovirus. These results indicated that ALK1 was involved and played a critical role in tumour angiogenesis induced by low‑dose PDT. Furthermore, ALK1 was found to participate in PDT‑induced tumour angiogenesis by activating the Smad1/5‑ID1 pathway, as opposed to the PI3K/AKT pathway. On the whole, the present study, for the first time, to the best of our knowledge, demonstrates that ALK1 is involved in PDT‑induced tumour angiogenesis. The inhibition of ALK1 can suppress PDT‑induced tumour angiogenesis, which can enhance the effects of PDT and may thus provide a novel treatment strategy for PDT.

Nanotechnology for colorectal cancer detection and treatment

Colorectal cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer-related mortality in the United States. Across the globe, people in the age group older than 50 are at a higher risk of CRC. Genetic and environmental risk factors play a significant role in the development of CRC. If detected early, CRC is preventable and treatable. Currently, available screening methods and therapies for CRC treatment reduce the incidence rate among the population, but the micrometastasis of cancer may lead to recurrence. Therefore, the challenge is to develop an alternative therapy to overcome this complication. Nanotechnology plays a vital role in cancer treatment and offers targeted chemotherapies directly and selectively to cancer cells, with enhanced therapeutic efficacy. Additionally, nanotechnology elevates the chances of patient survival in comparison to traditional chemotherapies. The potential of nanoparticles includes that they may be used simultaneously for diagnosis and treatment. These exciting properties of nanoparticles have enticed researchers worldwide to unveil their use in early CRC detection and as effective treatment. This review discusses contemporary methods of CRC screening and therapies for CRC treatment, while the primary focus is on the theranostic approach of nanotechnology in CRC treatment and its prospects. In addition, this review aims to provide knowledge on the advancement of nanotechnology in CRC and as a starting point for researchers to think about new therapeutic approaches using nanotechnology.

Self-delivery nanomedicine for vascular disruption-supplemented chemo-photodynamic tumor therapy

Tumor vascular blockade is a promising strategy for adjuvant cancer treatment. In this work, a self-delivery nanomedicine is developed based on a vascular disruptor and photosensitizer for tumor synergistic therapy. Specifically, this nanomedicine (designated as CeCA) is comprised of combretastatin A4 (CA4) and chlorine e6 (Ce6) by self-assembly technique. Among which, CA4 could not only induce tubulin inhibition for chemotherapy but also disrupt the vasculature to cause tumor hemorrhage. Moreover, Ce6 is able to generate lots of singlet oxygen (¹O₂) for synergistic photodynamic therapy (PDT) under light irradiation. It is interesting that the carrier-free CeCA possessed a favorable stability and an improved cellular uptake behavior. After intravenous administration, CeCA prefers to accumulate at tumor site for vascular disruption-supplemented chemo-photodynamic therapy. Notably, CeCA is prepared without additional carriers, which avoids the system toxicity raised by excipients. Consequently, CeCA greatly inhibits the tumor growth and leads to a low side effect in vivo. It might open a window in the development of self-supplementary nanomedicine for synergistic tumor treatment.

Organic Nanocarriers for Bevacizumab Delivery: An Overview of Development, Characterization and Applications

Bevacizumab (BCZ) is a recombinant humanized monoclonal antibody against the vascular endothelial growth factor, which is involved in the angiogenesis process. Pathologic angiogenesis is observed in several diseases including ophthalmic disorders and cancer. The multiple administrations of BCZ can cause adverse effects. In this way, the development of controlled release systems for BCZ delivery can promote the modification of drug pharmacokinetics and, consequently, decrease the dose, toxicity, and cost due to improved efficacy. This review highlights BCZ formulated in organic nanoparticles providing an overview of the physicochemical characterization and in vitro and in vivo biological evaluations. Moreover, the main advantages and limitations of the different approaches are discussed. Despite difficulties in working with antibodies, those nanocarriers provided advantages in BCZ protection against degradation guaranteeing bioactivity maintenance.

Possible Enhancement of Photodynamic Therapy (PDT) Colorectal Cancer Treatment when Combined with Cannabidiol

Colorectal Cancer (CRC) has a high mortality rate and is one of the most difficult diseases to manage due to tumour resistance and metastasis. The treatment of choice for CRC is reliant on the phase and time of diagnosis. Despite several conventional treatments available to treat CRC (surgical excision, chemo-, radiationand immune-therapy), resistance is a major challenge, especially if it has metastasized. Additionally, these treatments often cause unwanted adverse side effects and so it remains imperative to investigate alternative combination therapies. Photodynamic Therapy (PDT) is a promising treatment modality for the primary treatment of CRC, since it is non-invasive, has few side effects and selectively damages only cancerous tissues, leaving adjacent healthy structures intact. PDT involves three fundamentals: a Photosensitizer (PS) drug localized in tumour tissues, oxygen, and light. Upon PS excitation using a specific wavelength of light, an energy transfer cascade occurs, that ultimately yields cytotoxic species, which in turn induces cell death. Cannabidiol (CBD) is a cannabinoid compound derived from the Cannabis sativa plant, which has shown to exert anticancer effects on CRC through different pathways, inducing apoptosis and so inhibiting tumour metastasis and secondary spread. This review paper highlights current conventional treatment modalities for CRC and their limitations, as well as discusses the necessitation for further investigation into unconventional active nanoparticle targeting PDT treatments for enhanced primary CRC treatment. This can be administered in combination with CBD, to prevent CRC secondary spread and enhance the synergistic efficacy of CRC treatment outcomes, with less side effects.

Monotherapy and Combination Therapy Using Anti-Angiogenic Nanoagents to Fight Cancer

Anti-angiogenic therapy, targeting vascular endothelial cells (ECs) to prevent tumor growth, has been attracting increasing attention in recent years, beginning with bevacizumab (Avastin) through its Phase II/III clinical trials on solid tumors. However, these trials showed only modest clinical efficiency; moreover, anti-angiogenic therapy may induce acquired resistance to the drugs employed. Combining advanced drug delivery techniques (e.g., nanotechnology) or other therapeutic strategies (e.g., chemotherapy, radiotherapy, phototherapy, and immunotherapy) with anti-angiogenic therapy results in significantly synergistic effects and has opened a new horizon in fighting cancer. Herein, clinical difficulties in using traditional anti-angiogenic therapy are discussed. Then, several promising applications of anti-angiogenic nanoagents in monotherapies and combination therapies are highlighted. Finally, the challenges and perspectives of anti-angiogenic cancer therapy are summarized. A useful introduction to anti-angiogenic strategies, which may significantly improve therapeutic outcomes, is thus provided.

Nanomaterials for Antiangiogenic Therapies for Cancer: A Promising Tool for Personalized Medicine

Angiogenesis is one of the hallmarks of cancer. Several studies have shown that vascular endothelium growth factor (VEGF) plays a leading role in angiogenesis progression. Antiangiogenic medication has gained substantial recognition and is commonly administered in many forms of human cancer, leading to a rising interest in cancer therapy. However, this treatment method can lead to a deteriorating outcome of resistance, invasion, distant metastasis, and overall survival relative to its cytotoxicity. Furthermore, there are significant obstacles in tracking the efficacy of antiangiogenic treatments by incorporating positive biomarkers into clinical settings. These shortcomings underline the essential need to identify additional angiogenic inhibitors that target numerous angiogenic factors or to develop a new method for drug delivery of current inhibitors. The great benefits of nanoparticles are their potential, based on their specific properties, to be effective mechanisms that concentrate on the biological system and control various important functions. Among various therapeutic approaches, nanotechnology has emerged as a new strategy for treating different cancer types. This article attempts to demonstrate the huge potential for targeted nanoparticles and their molecular imaging applications. Notably, several nanoparticles have been developed and engineered to demonstrate antiangiogenic features. This nanomedicine could effectively treat a number of cancers using antiangiogenic therapies as an alternative approach. We also discuss the latest antiangiogenic and nanotherapeutic strategies and highlight tumor vessels and their microenvironments.

Engineering a photosensitizer nanoplatform for amplified photodynamic immunotherapy via tumor microenvironment modulation

Photosensitizer-based photodynamic therapy (PDT) can not only kill tumor cells by the generated cytotoxic reactive oxygen species (ROS), but also trigger immunogenic cell death (ICD) and activate an immune response for immunotherapy. However, such photodynamic immunotherapy suffers from major obstacles in the tumor microenvironment. The hypoxic microenvironment greatly weakens PDT, while the immunosuppressive tumor microenvironment caused by aberrant tumor blood vessels and indoleamine 2,3-dioxygenase (IDO) leads to a significant reduction in immunotherapy. To overcome these obstacles, herein, an engineered photosensitizer nanoplatform is designed for amplified photodynamic immunotherapy by integrating chlorin e6 (Ce6, a photosensitizer), axitinib (AXT, a tyrosine kinase inhibitor) and dextro-1-methyl tryptophan (1MT, an IDO inhibitor). In our nanoplatform, AXT improves the tumor microenvironment by normalizing tumor blood vessels, which not only promotes PDT by reducing the level of hypoxia of the tumor microenvironment, but also promotes immunotherapy through facilitating infiltration of immune effector cells into the tumor and reversing the immunosuppressive effect of vascular endothelial growth factor (VEGF). Moreover, 1MT effectively inhibits the activity of IDO, further reducing the immunosuppressive nature of the tumor microenvironment. Therefore, this nanoplatform demonstrates an amplified photodynamic immunotherapy via tumor microenvironment modulation, exhibiting outstanding therapeutic efficacy against tumor growth and metastasis with negligible side toxicity. The current concept of engineering photosensitizer nanoplatforms for overcoming photodynamic immunotherapy obstacles provides a promising strategy against tumors.

Combination Therapy by Tissue-Specific Suicide Gene and Bevacizumab in Intramedullary Spinal Cord Tumor

PURPOSE

Malignant gliomas are aggressive spinal cord tumors. In this study, we hypothesized that combination therapy using an anti-angiogenic agent, bevacizumab, and hypoxia-inducible glioblastoma-specific suicide gene could reduce tumor growth.

MATERIALS AND METHODS

In the present study, we evaluated the effect of combination therapy using bevacizumab and pEpo-NI2-SV-TK in reducing the proliferation of C6 cells and tumor growth in the spinal cord. Spinal cord tumor was generated by the injection of C6 cells into the T5 level of the spinal cord. Complexes of branched polyethylenimine (bPEI)/pEpo-NI2-SV-TK were injected into the spinal cord tumor. Bevacizumab was then administered by an intraperitoneal injection at a dose of 7 mg/kg. The anti-cancer effects of combination therapy were analyzed by histological analyses and magnetic resonance imaging (MRI). The Basso, Beattie and Bresnahan scale scores for all of the treatment groups were recorded every other day for 15 days to assess the rat hind-limb strength.

RESULTS

The complexes of bPEI/pEpo-NI2-SV-TK inhibited the viability of C6 cells in the hypoxia condition at 5 days after treatment with ganciclovir. Bevacizumab was decreased in the cell viability of human umbilical vein endothelial cells. Combination therapy reduced the tumor size by histological analyses and MRI. The combination therapy group showed improved hind-limb function compared to the other groups that were administered pEpo-NI2-SV-TK alone or bevacizumab alone.

CONCLUSION

This study suggests that combination therapy using bevacizumab with the pEpo-NI2-SV-TK therapeutic gene could be useful for increasing its therapeutic benefits for intramedullary spinal cord tumors.

The influence of photodynamic therapy on the Warburg effect in esophageal cancer cells

To investigate whether the Warburg effect is a key modulator on the resistance mechanism of photodynamic therapy (PDT). Glycolysis was examined by the test of lactate product and glucose uptake at different post-PDT time points. Cell viability was detected by the CCK-8 assay and cell proliferation was detected by colony formation assay. The expression of glycolysis and related proteins were examined by western blotting. Target gene was silenced by RNAi. In the present study, we assessed the effect of PDT on cancer cell glycolysis. Our team has demonstrated that pyruvate kinase M2 (PKM2), a key speed-limiting enzyme of glycolysis, was significantly overexpressed in patients with esophageal cancer. Our results in the present study showed that PKM2 was downregulated, and lactate product and glucose uptake were inhibited in cells exposed to 5-aminolevulinic acid (5-ALA)-mediated PDT at 4 h after treatment. However, at 24 h after PDT, we observed a substantial increase in PKM2 expression, lactate product, and glucose uptake. Moreover, silencing of PKM2 gene abrogated the upregulatory effect of PDT on glycolysis at late post-PDT period. 2-Deoxy-D-glucose (2-DG) is a recognized chemical inhibitor of glycolysis. The combined treatment of 2-DG and PDT significantly inhibited tumor growth in vitro at 24 h. These results demonstrate that PDT drives the Warburg effect in a time-dependent manner, and PKM2 plays an important role in this progress, which indicated that PKM2 may be a potential molecular target to increase the sensitivity of esophageal cancer cells to PDT.

Potentiality, Limitations, and Consequences of Different Experimental Models to Improve Photodynamic Therapy for Cancer Treatment in Relation to Antiangiogenic Mechanism

The relevance of experimentally gained information represents a long-term debating issue in the field of molecular biology research. The loss of original conditions in the in vitro environment affects various biological mechanisms and cellular interactions. Consequently, some biochemical mechanisms are lost or critically altered. Analyses in these modified conditions could, therefore, distort the relevancy of experimentally gained information. In some cases, the similarities with original conditions are so small that utilization of simpler in vitro models seems impossible, or could occur in a very limited way. To conclude, the study of more complex phenomena places higher demands on the complexity of the experimental model. The latest information highlights the fact that the tumor angiogenesis mechanism has very complex features. This complexity can be associated with a wide range of angiogenic factors expressed by a variety of malignant and non-malignant cells. Our article summarizes the results from various experimental models that were utilized to analyze a photodynamic therapy effect on tumor angiogenic mechanisms. Additionally, based on the latest information, we present the most important attributes and limitations of utilized experimental models. We also evaluate the essential problems associated with angiogenic mechanism induction after photodynamic therapy application.

A Highly-Efficient Type I Photosensitizer with Robust Vascular-Disruption Activity for Hypoxic-and-Metastatic Tumor Specific Photodynamic Therapy

Hypoxia severely impedes photodynamic therapy (PDT) efficiency. Worse still, considerable tumor metastasis will occur after PDT. Herein, an organic superoxide radical (O2∙- ) nano-photogenerator as a highly effcient type I photosensitizer with robust vascular-disrupting efficiency to combat these thorny issues is designed. Boron difluoride dipyrromethene (BODIPY)-vadimezan conjugate (BDPVDA) is synthesized and enwrapped in electron-rich polymer-brushes methoxy-poly(ethylene glycol)-b-poly(2-(diisopropylamino) ethyl methacrylate) (mPEG- PPDA) to afford nanosized hydrophilic type I photosensitizer (PBV NPs). Owing to outstanding core-shell intermolecular electron transfer between BDPVDA and mPEG-PPDA, remarkable O2∙- can be produced by PBV NPs under near-infrared irradiation even in severe hypoxic environment (2% O2 ), thus to accomplish effective hypoxic-tumor elimination. Simultaneously, the efficient ester-bond hydrolysis of BDPVDA in the acidic tumor microenvironment allows vadimezan release from PBV NPs to disrupt vasculature, facilitating the shut-down of metastatic pathways. As a result, PBV NPs will not only be powerful in resolving the paradox between traditional type II PDT and hypoxia, but also successfully prevent tumor metastasis after type I PDT treatment (no secondary-tumors found in 70 days and 100% survival rate), enabling enhancement of existing hypoxic-and-metastatic tumor treatment.

Enhancing Drug Delivery for Overcoming Angiogenesis and Improving the Phototherapy Efficacy of Glioblastoma by ICG-Loaded Glycolipid-Like Micelles

Background

Phototherapy is a potential new candidate for glioblastoma (GBM) treatment. However inadequate phototherapy due to stability of the photosensitizer and low target specificity induces the proliferation of neovascular endothelial cells for angiogenesis and causes poor prognosis.

Methods

In this study, we constructed c(RGDfk)-modified glycolipid-like micelles (cRGD-CSOSA) encapsulating indocyanine green (ICG) for dual-targeting neovascular endothelial cells and tumor cells, and cRGD-CSOSA/ICG mediated dual effect of PDT/PTT with NIR irradiation.

Results

In vitro, cRGD-CSOSA/ICG inhibited cell proliferation and blocked angiogenesis with NIR irradiation. In vivo, cRGD-CSOSA/ICG exhibited increased accumulation in neovascular endothelial cells and tumor cells. Compared with that of CSOSA, the accumulation of cRGD-CSOSA in tumor tissue was further improved after dual-targeted phototherapy pretreatment. With NIR irradiation, the tumor-inhibition rate of cRGD-CSOSA/ICG was 80.00%, significantly higher than that of ICG (9.08%) and CSOSA/ICG (42.42%). Histological evaluation showed that the tumor vessels were reduced and that the apoptosis of tumor cells increased in the cRGD-CSOSA/ICG group with NIR irradiation.

Conclusion

The cRGD-CSOSA/ICG nanoparticle-mediated dual-targeting phototherapy could enhance drug delivery to neovascular endothelial cells and tumor cells for anti-angiogenesis and improve the phototherapy effect of glioblastoma, providing a new strategy for glioblastoma treatment.

Anti-vascular nano agents: a promising approach for cancer treatment

Anti-vascular agents (AVAs) are a class of promising therapeutic agents with tumor vasculature targeting properties, which can be divided into two types: anti-angiogenic agents (AAAs, inhibit angiogenesis factors) and vascular disrupting agents (VDAs, disrupt established tumor vasculature). AVAs exhibit an enhanced anti-cancer effect by cutting off the oxygen and nutrition supplement channels of tumors. However, the intrinsic drawbacks, such as poor hydrophilicity, undesirable membrane permeability and inferior tumor targeting ability, discount their anti-vascular efficacy. Fortunately, the development of nanotechnology has brought an opportunity for efficient delivery of AVAs to tumour sites with great therapeutic efficacy. The works summarized in this review will provide an understanding of recent advances of anti-vascular nano agents (AVNAs) with a goal to define the mechanism of anti-vascular-based cancer therapy and discuss the challenges and opportunities of AVNAs for clinical translation.

Biomimetic Metal-Organic Framework Nanoparticles for Cooperative Combination of Antiangiogenesis and Photodynamic Therapy for Enhanced Efficacy

Photodynamic therapy (PDT) is a promising anticancer treatment and is clinically approved for different types of tumors. However, current PDT suffers several obstacles, including its neutralization by excess glutathione (GSH) in the tumor tissue and its strongly proangiogenic tumor response. In this work, a biomimic, multifunctional nanoparticle-based PDT agent, combining a tumor-targeted photosensitizer with GSH scavenging and antiangiogenesis therapy, is developed. A porphyrinic Zr-metal-organic framework nanoparticle is used simultaneously as the photosensitizer and the delivery vehicle of vascular endothelial growth factor receptor 2 (VEGFR2) inhibitor apatinib. The core nanoparticles are wrapped in MnO₂ to consume the intratumoral GSH and then decorated with a tumor cell membrane camouflage. After intravenous administration, the nanoparticles selectively accumulate in tumor through homotypic targeting mediated by the biomimic decoration, and the combination of enhanced PDT and antiangiogenic drug significantly improves their tumor inhibition efficiency. This study provides an integrated solution for mechanism-based enhancement of PDT and demonstrates the encouraging potential for multifunctional nanosystem applicable for tumor therapy.

The capability and potential of new forms of personalized colon cancer treatment: Immunotherapy and Photodynamic Therapy

INTRODUCTION

PDT can interfere with cytokine-mediated responses that play an important role in the processes of cancer progression, tumor angiogenesis and metastasis. Therefore, based on the identification of these cancer biomarkers, the therapy of combining various forms of treatment, including immunotherapy and PDT, may be a justified strategy for colorectal cancer treatment that focuses on individualized comprehensive therapy.

METHOD

We reviewed the major approaches on the use of immunotherapy in colorectal cancer, with the special regard to photodynamic therapy, its immunological effect and new oncological treatment directions, connected with adjuvant immunotherapy including use of nanoparticles. Databases such as PubMed, ScienceDirect and Springer were utilized to search the literature for relevant articles.

PURPOSE

To review studies of the immunotherapy in colon cancer and immune response to PDT.

CONCLUSION

Based on the identification of immunological cancer biomarkers, the therapy of combining various forms of treatment, including immunotherapy and PDT, may be a justified strategy for colorectal cancer treatment that focuses on individualized comprehensive therapy.