The Application of DVDMS as a Sensitizing Agent for Sono-/Photo-Therapy

Nanotechnology-enabled sonodynamic therapy against malignant tumors

Sonodynamic therapy (SDT) is an emerging approach for malignant tumor treatment, offering high precision, deep tissue penetration, and minimal side effects. The rapid advancements in nanotechnology, particularly in cancer treatment, have enhanced the efficacy and targeting specificity of SDT. Combining sonodynamic therapy with nanotechnology offers a promising direction for future cancer treatments. In this review, we first systematically discussed the anti-tumor mechanism of SDT and then summarized the common nanotechnology-related sonosensitizers and their recent applications. Subsequently, nanotechnology-related therapies derived using the SDT mechanism were elaborated. Finally, the role of nanomaterials in SDT combined therapy was also introduced.

Biofilm Producing Methicillin-Resistant Staphylococcus aureus (MRSA) Infections in Humans: Clinical Implications and Management

Since its initial description in the 1960s, methicillin-resistant Staphylococcus aureus (MRSA) has developed multiple mechanisms for antimicrobial resistance and evading the immune system, including biofilm production. MRSA is now a widespread pathogen, causing a spectrum of infections ranging from superficial skin issues to severe conditions like osteoarticular infections and endocarditis, leading to high morbidity and mortality. Biofilm production is a key aspect of MRSA's ability to invade, spread, and resist antimicrobial treatments. Environmental factors, such as suboptimal antibiotics, pH, temperature, and tissue oxygen levels, enhance biofilm formation. Biofilms are intricate bacterial structures with dense organisms embedded in polysaccharides, promoting their resilience. The process involves stages of attachment, expansion, maturation, and eventually disassembly or dispersion. MRSA's biofilm formation has a complex molecular foundation, involving genes like icaADBC, fnbA, fnbB, clfA, clfB, atl, agr, sarA, sarZ, sigB, sarX, psm, icaR, and srtA. Recognizing pivotal genes for biofilm formation has led to potential therapeutic strategies targeting elemental and enzymatic properties to combat MRSA biofilms. This review provides a practical approach for healthcare practitioners, addressing biofilm pathogenesis, disease spectrum, and management guidelines, including advances in treatment. Effective management involves appropriate antimicrobial therapy, surgical interventions, foreign body removal, and robust infection control practices to curtail spread within healthcare environments.

Photodynamic therapy augments oxaliplatin-induced immunogenic cell death in colorectal cancer

Colorectal cancer is one of the most frequently diagnosed cancers. Immunotherapy has been proven to be a potential treatment option for colorectal cancer. Colorectal cancer maintains immune escape by expressing low immunogenicity and following the tolerogenic cell death pathway. There is also emerging evidence that oxaliplatin and photodynamic therapy (PDT) can promote anti-tumor immunity. However, the effect of PDT combined with oxaliplatin on colorectal cancer remains elusive. Here, we analyzed the viability of HCT116 and DLD-1 cell lines after treatment with the combination of PDT and oxaliplatin. We found that the viability decreased significantly after the combination treatment. Meanwhile, we also detected that sinoporphyrin sodium (DVDMS)-derived PDT could amplify oxaliplatin-induced immunogenic cell death (ICD) in different colorectal cancer cell lines. More importantly, the combination of DVDMS-derived PDT and oxaliplatin presented strong immunogenic potential in immunocompetent BALB/c mice in the vaccination assay. Taken together, our data demonstrated that the combination of DVDMS-derived PDT and oxaliplatin is a potential novel therapy for colorectal cancer.

Antitumor Effects of Pegylated Zinc Protoporphyrin-Mediated Sonodynamic Therapy in Ovarian Cancer

Sonodynamic therapy (SDT) induces reactive oxygen species (ROS) to kill tumor cells. Heme oxygenase-1 (HO-1), as an important antioxidant enzyme, resists killing by scavenging ROS. Zinc protoporphyrin (ZnPP) not only effectively inhibits HO-1 activity, but also becomes a potential sonosensitizer. However, its poor water solubility limits its applications. Herein, we developed an improved water-soluble method. It was proved that pegylated zinc protoporphyrin-mediated SDT (PEG-ZnPP-SDT) could significantly enhance ROS production by destroying the HO-1 antioxidant system in ovarian cancer. Increased ROS could cause mitochondrial membrane potential collapse, release cytochrome c from mitochondria to the cytoplasm, and trigger the mitochondrial-caspase apoptotic pathway. In conclusion, our results demonstrated that PEG-ZnPP-SDT, as a novel sonosensitizer, could improve the antitumor effects by destroying the HO-1 antioxidant system. It provided a new therapeutic strategy for SDT to treat cancers, especially those with higher HO-1 expression.

Research progress on reactive oxygen species production mechanisms in tumor sonodynamic therapy

In recent years, because of the growing desire to improve the noninvasiveness and safety of tumor treatments, sonodynamic therapy has gradually become a popular research topic. However, due to the complexity of the therapeutic process, the relevant mechanisms have not yet been fully elucidated. One of the widely accepted possibilities involves the effect of reactive oxygen species. In this review, the mechanism of reactive oxygen species production by sonodynamic therapy (SDT) and ways to enhance the sonodynamic production of reactive oxygen species are reviewed. Then, the clinical application and limitations of SDT are discussed. In conclusion, current research on sonodynamic therapy should focus on the development of sonosensitizers that efficiently produce active oxygen, exhibit biological safety, and promote the clinical transformation of sonodynamic therapy.

Research progress on reactive oxygen species production mechanisms in tumor sonodynamic therapy

In recent years, because of the growing desire to improve the noninvasiveness and safety of tumor treatments, sonodynamic therapy has gradually become a popular research topic. However, due to the complexity of the therapeutic process, the relevant mechanisms have not yet been fully elucidated. One of the widely accepted possibilities involves the effect of reactive oxygen species. In this review, the mechanism of reactive oxygen species production by sonodynamic therapy (SDT) and ways to enhance the sonodynamic production of reactive oxygen species are reviewed. Then, the clinical application and limitations of SDT are discussed. In conclusion, current research on sonodynamic therapy should focus on the development of sonosensitizers that efficiently produce active oxygen, exhibit biological safety, and promote the clinical transformation of sonodynamic therapy.

Spotlight on porphyrins: Classifications, mechanisms and medical applications

Photodynamic therapy (PDT) and sonodynamic therapy (SDT) are non-invasive treatment methods with obvious inhibitory effect on tumors and have few side effects, which have been widely concerned and explored by researchers. Sensitizer is the main factor in determining the therapeutic effect of PDT and SDT. Porphyrins, a group of organic compounds widespread in nature, can be activated by light or ultrasound and produce reactive oxygen species. Therefore, porphyrins as sensitizers in PDT have been widely explored and investigated for many years. Herein, we summarize the classical porphyrin compounds and their applications and mechanisms in PDT and SDT. The application of porphyrin in clinical diagnosis and imaging is also discussed. In conclusion, porphyrins have good application prospects in disease treatment as an important part of PDT or SDT, and in clinical diagnosis and imaging.

Nanosensitizer-mediated unique dynamic therapy tactics for effective inhibition of deep tumors

X-ray and ultrasound waves are widely employed for diagnostic and therapeutic purposes in clinic. Recently, they have been demonstrated to be ideal excitation sources that activate sensitizers for the dynamic therapy of deep-seated tumors due to their excellent tissue penetration. Here, we focused on the recent progress in five years in the unique dynamic therapy strategies for the effective inhibition of deep tumors that activated by X-ray and ultrasound waves. The concepts, mechanisms, and typical nanosensitizers used as energy transducers are described as well as their applications in oncology. The future developments and potential challenges are also discussed. These unique therapeutic methods are expected to be developed as depth-independent, minimally invasive, and multifunctional strategies for the clinic treatment of various deep malignancies.

Triplex-forming oligonucleotides as an anti-gene technique for cancer therapy

Triplex-forming oligonucleotides (TFOs) can bind to the major groove of double-stranded DNA with high specificity and affinity and inhibit gene expression. Triplex-forming oligonucleotides have gained prominence because of their potential applications in antigene therapy. In particular, the target specificity of triplex-forming oligonucleotides combined with their ability to suppress oncogene expression has driven their development as anti-cancer agents. So far, triplex-forming oligonucleotides have not been used for clinical treatment and seem to be gradually snubbed in recent years. But triplex-forming oligonucleotides still represent an approach to down-regulate the expression of the target gene and a carrier of active substances. Therefore, in the present review, we will introduce the characteristics of triplex-forming oligonucleotides and their anti-cancer research progress. Then, we will discuss the challenges in their application.

Sonodynamic Therapy With Concentric Ultrasound Imaging Array for Precision Theranostics for Atherosclerotic Plaque

Atherosclerotic cardiovascular disease is a major cause of human disability and mortality. Our previous study demonstrated the safety and efficacy of sonodynamic therapy (SDT) on atherosclerotic plaques. However, traditional single-element therapeutic transducer has single acoustic field, and positioning therapeutic and imaging transducers in the same position is difficult during ultrasound imaging-guided SDT. Continuously changing the position of transducers to intervene lesions in different positions is required, increasing the difficulty of treatment. Thus, an SDT device with precise theranostics is required. Therefore, we designed and fabricated a "concentric ultrasound transducer for theranostics" (CUST-T), comprising a central 8-MHz linear array transducer for ultrasound imaging, and a peripheral 1-MHz hollow two-dimensional (2-D) planar array transducer for generating phased-array focused ultrasound (PAFUS). The CUST-T exhibited high imaging resolution at a distance of up to 20 mm from the transducer and could generate a personalized complex PAFUS acoustic field to match various lesions. In vitro biomedical results showed that PAFUS-SDT induced RAW264.7-derived foam cell apoptosis leading to a targeting field apoptotic rate 4.36-6.24 times that of the nontargeting field and the significant apoptotic region was consistent with the PAFUS acoustic field. In vivo, PAFUS-SDT guided by ultrasound imaging significantly increased the lumen area ( ) and collagen level ( ), whereas the wall thickness ( ) and lipid content ( ) of rabbit femoral artery were reduced. In conclusion, CUST-T provided image guidance sufficient for accurate SDT for atherosclerotic plaques in peripheral arteries and could be applied in clinical practice.

Precision Killing of Sinoporphyrin Sodium-Mediated Photodynamic Therapy against Malignant Tumor Cells

Photodynamic therapy (PDT) has significant advantages in the treatment of malignant tumors, such as high efficiency, minimal invasion and less side effects, and it can preserve the integrity and quality of the organs. The power density, irradiation time and photosensitizer (PS) concentration are three main parameters that play important roles in killing tumor cells. However, until now, the underlying relationships among them for PDT outcomes have been unclear. In this study, human malignant glioblastoma U-118MG and melanoma A375 cells were selected, and the product of the power density, irradiation time and PS concentration was defined as the total photodynamic parameter (TPP), in order to investigate the mechanisms of PS sinoporphyrin sodium (DVDMS)-mediated PDT (DVDMS-PDT). The results showed that the survival rates of the U-118MG and A375 cells were negatively correlated with the TPP value in the curve, and the correlation exactly filed an e-exponential function. Moreover, according to the formula, we realized controllable killing effects of the tumor cells by randomly adjusting the three parameters, and we finally verified the accuracy and repeatability of the formula. In conclusion, the establishment and implementation of a newly functional relationship among the PDT parameters are essential for predicting PDT outcomes and providing personalized precise treatment, and they are contributive to the development of PDT dosimetry.

Application of metalloporphyrin sensitizers for the treatment or diagnosis of tumors

At present, metalloporphyrin compounds demonstrate three main uses as anticancer sensitizers: (1) photosensitizers, (2) photothermal conversion agents, and (3) ultrasound sensitizers. Developing efficient sensitizers for cancer with excellent controllability and biocompatibility is an important goal of oncology medicine. Because of the different structural diversity of anticancer sensitizers, such sensitizers are used for treating cancers by employing a variety of tumor treatment methods such as mature photodynamic therapy, commonly used clinically photothermal therapy and promising sonodynamic therapy. Among the many sensitizers, metalloporphyrin-complex sensitizers attract wide attention due to their excellent performance in tumor treatment and diagnosis. This review briefly describes some metalloporphyrin anticancer drugs and diagnostic agents related to photodynamic, photothermal and sonodynamic therapy, and discusses the roles of metal atoms in these drugs.

Application of Self-Assembly Nanoparticles Based on DVDMS for Fenton-Like Ion Delivery and Enhanced Sonodynamic Therapy

Upon harnessing low-intensity ultrasound to activate sonosensitizers, sonodynamic therapy (SDT) induces cancer cell death through the reactive oxygen species (ROS) mediated pathway. Compared with photodynamic therapy (PDT), SDT possesses numerous advantages, including deeper tissue penetration, higher accuracy, fewer side effects, and better patient compliance. Sinoporphyrin sodium (DVDMS), a sonosensitizer approved by the FDA, has drawn abundant attention in clinical research, but there are some deficiencies. In order to further improve the efficiency of DVDMS, many studies have applied self-assembly nanotechnology to modify it. Furthermore, the combined applications of SDT/chemodynamic therapy (CDT) have become a research hotspot in tumor therapy. Therefore, we explored the self-assembly of nanoparticles based on DVDMS and copper to combine SDT and CDT. A cost-effective sonosensitizer was synthesized by dropping CuCl₂ into the DVDMS solution with the assistance of PVP. The results revealed that the nanostructures could exert excellent treatment effects on tumor therapy and perform well for PET imaging, indicating the potential for cancer theranostics. In vitro and in vivo experiments showed that the nanoparticles have outstanding biocompatibility, higher ROS production efficiency, and antitumor efficacy. We believe this design can represent a simple approach to combining SDT and CDT with potential applications in clinical treatment and PET imaging.

Hematoporphyrin Is a Promising Sensitizer for Dual-Frequency Sono-photodynamic Therapy in Mice Breast Cancer

Background: The combination of sonodynamic and photodynamic therapy (SPDT) may be a new hopeful non-invasive method for cancer treatment, which incorporates a combination of low-intensity ultrasound, laser radiation, and a sensitizer agent. Objectives: This study aimed at evaluating the effects of hematoporphyrin (HP)-mediated SPDT (dual-frequency ultrasound and laser radiation) in the management of mice breast adenocarcinoma. Methods: One hundred and thirty-two female mice with implanted tumors were divided into 22 groups, including sham, laser, 4 groups of dual-frequency ultrasound/laser radiation, 8 groups of HP-mediated SPDT (2.5 and 5 mg/kg), and 8 groups of HP encapsulated in mesoporous silica nanoparticles (HP-MSNs)-mediated SPDT. The sensitizer was administered by intraperitoneal injection and after a 24-hour delay, tumor grafted mice were treated with a combination of dual-frequency ultrasound and laser light. The tumor growth factors were used to assess the treatment outcome. Results: The results indicated that HP or HP-MSNs-mediated SPDT had a delaying tumor growth effect. In the groups treated with dual-frequency ultrasound and laser radiation, the maximum tumor growth inhibition (TGI) ratio was 47.5%, while the maximum TGI ratio in the SPDT groups was 61.6%. The time of T2 and T5 in the case of HP-MSNs-mediated SPDT groups was increased compared with sham and that of HP-mediated SPDT groups (P < 0.05). The inhibition ratio on tumor growth increased in all SPDT groups at 12 days after the treatment. Analysis of experimental data demonstrates that this increase was not declined and persisted over 30 days of treatment. The results indicated that SPDT is effective in relative tumor volume when compared with the sham group (339.1 ± 161 and 1510.8 ± 160, respectively). HP or HP-MSNs-mediated SPDT groups had Grade I (low), while others had Grade III (high) malignancy in the histological study of mice breast adenocarcinoma. Conclusions: The results revealed that when sensitized by dual-frequency SPDT, hematoporphyrin (with and without MSNs), has a promising effect at delaying tumor growth on mice breast cancer. Therefore, it can be appreciated that careful selection of the sensitizer with SPDT will play an eminent role in the success of cancer therapies.

Antimicrobial Photodynamic Therapy: Latest Developments with a Focus on Combinatory Strategies

Antimicrobial photodynamic therapy (aPDT) has become a fundamental tool in modern therapeutics, notably due to the expanding versatility of photosensitizers (PSs) and the numerous possibilities to combine aPDT with other antimicrobial treatments to combat localized infections. After revisiting the basic principles of aPDT, this review first highlights the current state of the art of curative or preventive aPDT applications with relevant clinical trials. In addition, the most recent developments in photochemistry and photophysics as well as advanced carrier systems in the context of aPDT are provided, with a focus on the latest generations of efficient and versatile PSs and the progress towards hybrid-multicomponent systems. In particular, deeper insight into combinatory aPDT approaches is afforded, involving non-radiative or other light-based modalities. Selected aPDT perspectives are outlined, pointing out new strategies to target and treat microorganisms. Finally, the review works out the evolution of the conceptually simple PDT methodology towards a much more sophisticated, integrated, and innovative technology as an important element of potent antimicrobial strategies.

Antibacterial Sonodynamic Therapy: Current Status and Future Perspectives

Multidrug-resistant bacteria have emerged in both community and hospital settings, partly due to the misuse of antibiotics. The inventory of viable antibiotics is rapidly declining, and efforts toward discovering newer antibiotics are not yielding the desired outcomes. Therefore, alternate antibacterial therapies based on physical mechanisms such as light and ultrasound are being explored. Sonodynamic therapy (SDT) is an emerging therapeutic approach that involves exposing target tissues to a nontoxic sensitizing chemical and low-intensity ultrasound. SDT can enable site-specific cytotoxicity by producing reactive oxygen species (ROS) in response to ultrasound, which can be harnessed for treating bacterial infections. This approach can potentially be used for both superficial and deep-seated microbial infections. The majority of the sonosensitizers reported are nonpolar, exhibiting limited bioavailability and a high clearance rate in the body. Therefore, targeted delivery agents such as nanoparticle composites, liposomes, and microbubbles are being investigated. This article reviews recent developments in antibacterial sonodynamic therapy, emphasizing biophysical and chemical mechanisms, novel delivery agents, ultrasound exposure and image guidance strategies, and the challenges in the pathway to clinical translation.

Dual-sonosensitizer loaded phase-transition nanoparticles with tumor-targeting for synergistically enhanced sonodynamic therapy

Sonodynamic therapy (SDT) is a fast-growing therapy activated by using ultrasound to initiate a catalytic reaction of sensitizing agents and kill tumor cells through producing reactive oxygen species (ROS). Both sinoporphyrin sodium (DVDMS) and IR780 are preeminent sonosensitizers and have been used in SDT alone. In this study, tumor targeting multifunctional composite nanoparticles (DVDMS@IR780@PFP@PLGA, DIPP-NPs) were synthesized by encapsulating DVDMS, IR780 and perfluoropentane (PFP) to synergistically enhance SDT and achieve imaging of tumors. The loaded IR780 is regarded as a "navigator" to accurately identify and target tumor cells/tissues. DVDMS and IR780 not only can realize the directed SDT, but also can perform photoacoustic (PA) imaging. PFP plays its role in enhancing the ultrasound (US) imaging. Generally, DIPP-NPs not only have an obvious synergistic anti-tumor effect, but also are able to carry out dual-mode imaging, which paves a promising way for tumor therapy.

Sonodynamic Therapy for the Treatment of Intracranial Gliomas

High-grade gliomas are the most common and aggressive malignant primary brain tumors. Current therapeutic schemes include a combination of surgical resection, radiotherapy and chemotherapy; even if major advances have been achieved in Progression Free Survival and Overall Survival for patients harboring high-grade gliomas, prognosis still remains poor; hence, new therapeutic options for malignant gliomas are currently researched. Sonodynamic Therapy (SDT) has proven to be a promising treatment combining the effects of low-intensity ultrasound waves with various sound-sensitive compounds, whose activation leads to increased immunogenicity of tumor cells, increased apoptotic rates and decreased angiogenetic potential. In addition, this therapeutic technique only exerts its cytotoxic effects on tumor cells, while both ultrasound waves and sensitizing compound are non-toxic per se. This review summarizes the present knowledge regarding mechanisms of action of SDT and currently available sonosensitizers and focuses on the preclinical and clinical studies that have investigated its efficacy on malignant gliomas. To date, preclinical studies implying various sonosensitizers and different treatment protocols all seem to confirm the anti-tumoral properties of SDT, while first clinical trials will soon start recruiting patients. Accordingly, it is crucial to conduct further investigations regarding the clinical applications of SDT as a therapeutic option in the management of intracranial gliomas.

Sonodynamic therapy reduces iron retention of hemorrhagic plaque

Intraplaque hemorrhage (IPH) plays a major role in the aggressive progression of vulnerable plaque, leading to acute cardiovascular events. We previously demonstrated that sonodynamic therapy (SDT) inhibits atherosclerotic plaque progression. In this study, we investigated whether SDT could also be applied to treat more advanced hemorrhagic plaque and addressed the underlying mechanism. SDT decreased atherosclerotic burden, positively altered atherosclerotic lesion composition, and alleviated iron retention in rabbit hemorrhagic plaques. Furthermore, SDT reduced iron retention by stimulating ferroportin 1 (Fpn1) expression in apolipoprotein E (ApoE)-/- mouse plaques with high susceptibility to IPH. Subsequently, SDT inhibited iron-overload-induced foam-cell formation and pro-inflammatory cytokines secretion in vitro. Moreover, SDT reduced levels of the labile iron pool and ferritin expression via the reactive oxygen species (ROS)-nuclear factor erythroid 2-related factor 2 (Nrf2)-FPN1 pathway. SDT exerted therapeutic effects on hemorrhagic plaques and reduced iron retention via the ROS-Nrf2-FPN1 pathway in macrophages, thereby suggesting that it is a potential translational strategy for patients with advanced atherosclerosis in clinical practice.

In Vitro Application of Sonodynamic Antimicrobial Chemotherapy as a Sonobactericidal Therapeutic Approach for Bacterial Infections: A Systematic Review and Meta-analysis

Introduction: This study aimed to perform a systematic review of the literature followed by a meta-analysis about the efficacy of sonodynamic antimicrobial chemotherapy (SACT) in bacterial infections. Methods: According to the PICOS (population, intervention, comparison and outcome) recommendations and PRISMA guidelines, an electronic search was conducted in PubMed, SCOPUS, Embase, and Cochrane Library based on the MeSH terms. All analyses were conducted using Biostat's Comprehensive Meta-Analysis version 2.0. The inter-study heterogeneity and publication bias assessments were carried out on the studies using I2 and the Egger's regression test. Results: Initially, 126 articles were identified in the electronic search, and 14 studies remained after analysis and exclusion of the duplicated studies and eligibility criteria. All results from the included studies displayed a significant reduction of microorganisms. The meta-analysis demonstrated a significant reduction in the bacterial load in all analyses (0.944% [95% CI, 0.901-0.969%; P=0.000]). Also, there was a low risk of bias for microbial load reduction without the evidence of publication bias. Conclusion: The results highlight that there is scientific evidence emphasizing the effectiveness of SACT in reducing the count of microorganisms in bacterial infections.

Sonodynamic therapy in combination with photodynamic therapy shows enhanced long-term cure of brain tumor

This article presents the construction of a multimodality platform that can be used for efficient destruction of brain tumor by a combination of photodynamic and sonodynamic therapy. For in vivo studies, U87 patient-derived xenograft tumors were implanted subcutaneously in SCID mice. For the first time, it has been shown that the cell-death mechanism by both treatment modalities follows two different pathways. For example, exposing the U87 cells after 24 h incubation with HPPH [3-(1'-hexyloxy)ethyl-3-devinyl-pyropheophorbide-a) by ultrasound participate in an electron-transfer process with the surrounding biological substrates to form radicals and radical ions (Type I reaction); whereas in photodynamic therapy, the tumor destruction is mainly caused by highly reactive singlet oxygen (Type II reaction). The combination of photodynamic therapy and sonodynamic therapy both in vitro and in vivo have shown an improved cell kill/tumor response, that could be attributed to an additive and/or synergetic effect(s). Our results also indicate that the delivery of the HPPH to tumors can further be enhanced by using cationic polyacrylamide nanoparticles as a delivery vehicle. Exposing the nano-formulation with ultrasound also triggered the release of photosensitizer. The combination of photodynamic therapy and sonodynamic therapy strongly affects tumor vasculature as determined by dynamic contrast enhanced imaging using HSA-Gd(III)DTPA.

Sinoporphyrin sodium, a novel sensitizer for photodynamic and sonodynamic therapy

Sinoporphyrin sodium (DVDMS) is a novel sensitizer discovered by Professor Fang Qi-Cheng and widely used in photodynamic (PDT) and sonodynamic therapy (SDT). We searched databases including PubMed, Web of Science, CNKI, etc. for system review of its progress. We found that, both DVDMS-PDT and -SDT had been proven effective for inhibiting tumor growth and mechanisms involved reactive oxygen species, autophagy, and mitochondrial apoptosis pathways. Material advances enhanced antitumor effects and expanded its application. The safety of DVDMS in animals was evaluated, and metabolic parameters were uncovered. Additionally, DVDMS-PDT also exhibited therapeutic effects on non-neoplastic diseases like psoriasis and bacterial infections. Two phase I clinical trials of DVDMS have been documented, but recruitments had still not been completed. In conclusion, DVDMS is a promising sensitizer for both PDT and SDT; however, there are some shortcomings in previous studies like inconsistent treatment parameters, which need systematic assessments in future. Moreover, more mechanisms such as the role of autophagy need to be discovered. Further evidence of the safety and effectiveness of new materials are needed, and the application in non-neoplastic diseases like actinic keratosis and fungal infection deserves further development. Above all, promoting its clinical applications is the most important goal.

An in vitro study on sonodynamic treatment of human colon cancer cells using sinoporphyrin sodium as sonosensitizer

BACKGROUND

Colorectal cancer is the third leading cause of cancer-related deaths worldwide. Sonodynamic therapy (SDT) is an emerging cancer therapy, and in contrast to photodynamic therapy, could non-invasively reach deep-seated tissues and locally activates a sonosensitizer preferentially accumulated in the tumor area to produce cytotoxicity effects. In comparison with traditional treatments, SDT may serve as an alternative strategy for human colon cancer treatment. Here, we investigated the sonodynamic effect using sinoporphyrin sodium (DVDMS) as a novel sonosensitizer on human colon cancer cells in vitro.

RESULTS

The absorption spectra of DVDMS revealed maximum absorption at 363 nm wavelength and emission peak at 635 nm. Confocal microscopy images revealed the DVDMS was primarily localized in the cytoplasm, while no evident signal was detected within the nuclei. Flow cytometry analysis showed rapid intracellular uptake of DVDMS by two types of human colon cancer cells (HCT116 and RKO). Cell viability of HCT116 was tolerant with the concentration of DVDMS up to 20 µg/mL, while the case of RKO was 5 µg/mL. In comparison with the control group, the SDT-treated groups of these two types of human colon cancer cells showed significant increase in cellular apoptosis and necrosis ratio. Increased intracellular reactive oxygen species (ROS) production was detected, indicating the involvement of ROS in mediating SDT effects.

CONCLUSION

DVDMS results an effective sonosensitizer for the ultrasound-mediated cancer cell killing, and its anticancer effect seems to rely on its ability to produce ROS under ultrasound exposure.