Photodynamic Therapy for Metastatic Melanoma Treatment: A Review

Localised light delivery on melanoma cells using optical microneedles

Light-based therapy is an emerging treatment for skin cancer, which has received increased attention due to its drug-free and non-invasive approach. However, the limitation of current light therapy methods is the inability for light to penetrate the skin and reach deep lesions. As such, we have developed a polylactic acid (PLA) microneedles array as a novel light transmission platform to perform in vitro evaluation regarding the effect of light therapy on skin cancer. For the first time, we designed and fabricated a microneedle array system with a height fixation device that can be installed in a cell culture dish and an LED array for blue light irradiation. The effect of the blue light combined with the microneedles on cell apoptosis was evaluated using B16F10 melanoma cells and analyzed by Hoechst staining. Our results demonstrate that blue light can be transmitted by microneedles to skin cells and effectively affect cell viability.

B16 Membrane-Coated Vesicles for Combined Photodynamic Therapy and Immunotherapy Shift Immune Microenvironment of Melanoma

Introduction

Coating of nanomedicine with cell membranes has attracted increasing attention as it can boost biocompatibility and improve the efficiency of treatment. Herein, we prepared innovative tumor cell-membrane-coated vesicles based on photodynamic therapy (PDT) drug indocyanine green (ICG) and explore the effect on melanoma in vitro and in vivo.

Methods

ICG was coated with B16 cell membranes (I@BM NVs) by sonication and extrusion, and the morphological characteristics of I@BM NVs were evaluated by transmission electron microscopy (TEM) and NP-tracking analysis. Homologous cellular uptake was evaluated by flow cytometry (FCM) after staining by DiD dye. Cellular cytotoxicity was evaluated by cell counting kit-8 assay and the anti-tumor effect in vitro was assessed by FCM and western blotting. The anti-tumor effect in vivo was evaluated in a B16 xenograft model in mice. The tumor micro-environment was investigated by FCM and real-time PCR.

Results

The vesicles are stable and uniform in nature, and show strong homologous targeting in vivo and in vitro. The vesicles can generate reactive oxygen species to induce apoptosis of B16 cells under near-infrared irradiation. Furthermore, the I@BM NVs induce a significant anti-tumor response in vivo, and perform better with respect to both tumor growth inhibition and lifespan extension. Analysis of immunocytes in the tumor microenvironment showed significant reductions in numbers of myeloid-derived suppressor cells and tumor-associated M2 macrophages in mice in the I@BM NVs group. This was accompanied by significant increases in numbers of M1 macrophages and proliferative CD4⁺/CD8⁺ T cells. Expression levels of IFN-γ and IL-2 increased in the I@BM NVs group, while expression of TGF-β and IL-10 decreased.

Conclusion

The results show that the I@BM NVs are feasible drugs for the treatment of melanoma by inducing cell apoptosis under NIR and shifting the immunosuppressive tumor microenvironment in vivo.

Oxidative Stress-Related Mechanisms in Melanoma and in the Acquired Resistance to Targeted Therapies

Melanoma is a highly aggressive cancer with the poorest prognosis, representing the deadliest form of skin cancer. Activating mutations in BRAF are the most frequent genetic alterations, present in approximately 50% of all melanoma cases. The use of specific inhibitors towards mutant BRAF variants and MEK, a downstream signaling target of BRAF in the MAPK pathway, has significantly improved progression-free and overall survival in advanced melanoma patients carrying BRAF mutations. Nevertheless, despite these improvements, resistance still develops within the first year of therapy in around 50% of patients, which is a significant problem in managing BRAF-mutated advanced melanoma. Understanding these mechanisms is one of the mainstreams of the research on BRAFi/MEKi acquired resistance. Both genetic and epigenetic mechanisms have been described. Moreover, in recent years, oxidative stress has emerged as another major force involved in all the phases of melanoma development, from initiation to progression until the onsets of the metastatic phenotype and chemoresistance, and has thus become a target for therapy. In the present review, we discuss the current knowledge on oxidative stress and its signaling in melanoma, as well as the oxidative stress-related mechanisms in the acquired resistance to targeted therapies.

Photodynamic Therapy-Mediated Immune Responses in Three-Dimensional Tumor Models

Photodynamic therapy (PDT) is a promising non-invasive phototherapeutic approach for cancer therapy that can eliminate local tumor cells and produce systemic antitumor immune responses. In recent years, significant efforts have been made in developing strategies to further investigate the immune mechanisms triggered by PDT. The majority of in vitro experimental models still rely on the two-dimensional (2D) cell cultures that do not mimic a three-dimensional (3D) cellular environment in the human body, such as cellular heterogeneity, nutrient gradient, growth mechanisms, and the interaction between cells as well as the extracellular matrix (ECM) and therapeutic resistance to anticancer treatments. In addition, in vivo animal studies are highly expensive and time consuming, which may also show physiological discrepancies between animals and humans. In this sense, there is growing interest in the utilization of 3D tumor models, since they precisely mimic different features of solid tumors. This review summarizes the characteristics and techniques for 3D tumor model generation. Furthermore, we provide an overview of innate and adaptive immune responses induced by PDT in several in vitro and in vivo tumor models. Future perspectives are highlighted for further enhancing PDT immune responses as well as ideal experimental models for antitumor immune response studies.

Nanoparticle-Based Drug Delivery Systems for Photodynamic Therapy of Metastatic Melanoma: A Review

Metastatic melanoma (MM) is a skin malignancy arising from melanocytes, the incidence of which has been rising in recent years. It poses therapeutic challenges due to its resistance to chemotherapeutic drugs and radiation therapy. Photodynamic therapy (PDT) is an alternative non-invasive modality that requires a photosensitizer (PS), specific wavelength of light, and molecular oxygen. Several studies using conventional PSs have highlighted the need for improved PSs for PDT applications to achieve desired therapeutic outcomes. The incorporation of nanoparticles (NPs) and targeting moieties in PDT have appeared as a promising strategy to circumvent various drawbacks associated with non-specific toxicity, poor water solubility, and low bioavailability of the PSs at targeted tissues. Currently, most studies investigating new developments rely on two-dimensional (2-D) monocultures, which fail to accurately mimic tissue complexity. Therefore, three-dimensional (3-D) cell cultures are ideal models to resemble tumor tissue in terms of architectural and functional properties. This review examines various PS drugs, as well as passive and active targeted PS nanoparticle-mediated platforms for PDT treatment of MM on 2-D and 3-D models. The overall findings of this review concluded that very few PDT studies have been conducted within 3-D models using active PS nanoparticle-mediated platforms, and so require further investigation.

Nanoparticle-Mediated Delivery Systems in Photodynamic Therapy of Colorectal Cancer

Colorectal cancer (CRC) involving a malignant tumour remains one of the greatest contributing causes of fatal mortality and has become the third globally ranked malignancy in terms of cancer-associated deaths. Conventional CRC treatment approaches such as surgery, radiation, and chemotherapy are the most utilized approaches to treat this disease. However, they are limited by low selectivity and systemic toxicity, so they cannot completely eradicate this disease. Photodynamic therapy (PDT) is an emerging therapeutic modality that exerts selective cytotoxicity to cancerous cells through the activation of photosensitizers (PSs) under light irradiation to produce cytotoxic reactive oxygen species (ROS), which then cause cancer cell death. Cumulative research findings have highlighted the significant role of traditional PDT in CRC treatment; however, the therapeutic efficacy of the classical PDT strategy is restricted due to skin photosensitivity, poor cancerous tissue specificity, and limited penetration of light. The application of nanoparticles in PDT can mitigate some of these shortcomings and enhance the targeting ability of PS in order to effectively use PDT against CRC as well as to reduce systemic side effects. Although 2D culture models are widely used in cancer research, they have some limitations. Therefore, 3D models in CRC PDT, particularly multicellular tumour spheroids (MCTS), have attracted researchers. This review summarizes several photosensitizers that are currently used in CRC PDT and gives an overview of recent advances in nanoparticle application for enhanced CRC PDT. In addition, the progress of 3D-model applications in CRC PDT is discussed.

BODIPY-Ruthenium(II) Bis-Terpyridine Complexes for Cellular Imaging and Type-I/-II Photodynamic Therapy

A series of multichromophoric ruthenium(II) complexes with the formulation [Ru(tpy-BODIPY)(tpy-R)]Cl2 (1-4), having a heteroleptic Ru(II)-bis-tpy (tpy = 4'-phenyl-2,2':6',2″-terpyridine) moiety covalently linked to a boron-dipyrromethene (BODIPY) pendant, have been prepared and characterized and their application as a phototherapeutic and photodetection agent in cancer therapy has been explored. Ligand L1 with a terpyridine-BODIPY moiety and complex 1 as its PF6 salt (1a) have been structurally characterized by a single-crystal X-ray diffraction study. Complex 1a has a distorted-octahedral RuN6 core with a Ru(II)-bis-terpyridine unit that is covalently linked to one photoactive BODIPY unit. The complexes exhibit strong absorbance near 502 nm (ε ≈ (3.7-7.8) × 104 M-1 cm-1) and high singlet oxygen sensitization ability, giving singlet oxygen quantum yield (ΦΔ) values ranging from 0.57 to 0.75 in DMSO. An emission-based study using complex 4 and Singlet Oxygen Sensor Green (SOSG) displays the formation of singlet oxygen inside the cells and also in the buffer medium upon light irradiation. DNA (pUC19) photocleavage experiments using ROS scavengers/stabilizers reveal photoinduced generation of singlet oxygen by a type-II process and of the superoxide anion radical by a type-I process. Complex 4 having a pendant biotin moiety as a cancer cell targeting group shows high photocytotoxicity with a remarkable phototherapeutic index (PI) value of >1400 in HeLa cancer cells with a low light dose activation (400-700 nm, 2.2 J cm-2). The complexes display reduced activity in noncancerous HPL1D cells. The emission property of the complexes is used for cellular imaging, thus making them suitable as next-generation theranostic PDT agents.

The Role of Melanoma Cell-Derived Exosomes (MTEX) and Photodynamic Therapy (PDT) within a Tumor Microenvironment

Photodynamic Therapy (PDT), an unconventional cancer therapy with optimistic desirable effects, utilizes the delivery of a photosensitizer (PS) that is activated by light at a particular wavelength and inducing oxidative cytotoxic damage of a tumor and its surrounding vasculature. Deeper seated tumors such as internally metastasized melanomas are more difficult to treat with PDT as the penetration of laser light to those sites is less. Limitations in targeting melanomas can also be attributed to melanin pigments that hinder laser light from reaching targeted sites. Exosomes serve as naturally occurring nanoparticles that can be re-assembled with PSs, improving targeted cellular absorption of photosensitizing agents during PDT. Additionally, studies indicate that exosomes released from PDT-treated tumor cells play a critical role in mediating anti-tumor immune responses. This review collates the role of Melanoma Cell-Derived Exosomes (MTEX) in immune response mediation and metastasis. Tumor Cell-Derived Exosomes (TEX) post PDT treatment are also reviewed, as well as the effects of exosomes as carriers of photosensitizers and delivery systems for PDT. The understanding and research on the role of melanoma exosomes induced by Photodynamic Therapy and their tumor microenvironment will assist in future research in treatment prospects and implications.

Antibody-Based Targeted Interventions for the Diagnosis and Treatment of Skin Cancers

BACKGROUND

Cutaneous malignancies most commonly arise from skin epidermal cells. These cancers may rapidly progress from benign to a metastatic phase. Surgical resection represents the gold standard therapeutic treatment of non-metastatic skin cancer while chemo- and/or radiotherapy are often used against metastatic tumors. However, these therapeutic treatments are limited by the development of resistance and toxic side effects, resulting from the passive accumulation of cytotoxic drugs within healthy cells.

OBJECTIVE

This review aims to elucidate how the use of monoclonal Antibodies (mAbs) targeting specific Tumor Associated Antigens (TAAs) is paving the way to improved treatment. These mAbs are used as therapeutic or diagnostic carriers that can specifically deliver cytotoxic molecules, fluorophores or radiolabels to cancer cells that overexpress specific target antigens.

RESULTS

mAbs raised against TAAs are widely in use for e.g. differential diagnosis, prognosis and therapy of skin cancers. Antibody-Drug Conjugates (ADCs) particularly show remarkable potential. The safest ADCs reported to date use non-toxic photo-activatable Photosensitizers (PSs), allowing targeted Photodynamic Therapy (PDT) resulting in targeted delivery of PS into cancer cells and selective killing after light activation without harming the normal cell population. The use of near-infrared-emitting PSs enables both diagnostic and therapeutic applications upon light activation at the specific wavelengths.

CONCLUSION

Antibody-based approaches are presenting an array of opportunities to complement and improve current methods employed for skin cancer diagnosis and treatment.

Comparison of the Photodynamic Action of Porphyrin, Chlorin, and Isobacteriochlorin Derivatives toward a Melanotic Cell Line

Melanoma is the most dangerous form of skin cancer, with an abrupt growth of its incidence over the last years. It is extremely resistant to traditional treatments such as chemotherapy and radiotherapy, but therapies for this cancer are gaining attention. Photodynamic therapy (PDT) is considered an effective modality to treat several types of skin cancers and can offer the possibility to treat one of the most aggressive ones: melanoma. In this work, the effect of PDT on a melanotic cell line (B16F10 cells) was assessed by exposing cultured cells to 5,10,15-tris(pentafluorophenyl)-20-(4-pyridyl)porphyrin (PS1) and to its chlorin (PS2) and isobacteriochlorin (PS3) corresponding derivatives and red LED light (λ = 660 ± 20 nm). The PDT effect in the cells' viability was measured using the MTT assay. The cell apoptosis was quantified by flow cytometry, and the subcellular localization of the photosensitizer was determined by fluorescence microscopy. In addition, the ability of PS2 to generate superoxide radicals was qualitatively assessed by tyrosine nitration. The results show that the efficiency of the PDT process is dependent on the structure of the PS and on their ability to produce singlet oxygen. Besides that, the photoactivation efficiency is highly dependent on the cellular sublocalization of the PS and on its cellular uptake and singlet oxygen production. We also found that the resistant cell line B16F10 has distinctive chlorin, isobacteriochlorin, or porphyrin-specific resistance profiles. Furthermore, it is shown that the highly fluorescent chlorin derivative PS2 can also be considered in imaging diagnostics.

Chimeric Antigen Receptor (CAR) T Cell Therapy for Metastatic Melanoma: Challenges and Road Ahead

Metastatic melanoma is the most aggressive and difficult to treat type of skin cancer, with a survival rate of less than 10%. Metastatic melanoma has conventionally been considered very difficult to treat; however, recent progress in understanding the cellular and molecular mechanisms involved in the tumorigenesis, metastasis and immune escape have led to the introduction of new therapies. These include targeted molecular therapy and novel immune-based approaches such as immune checkpoint blockade (ICB), tumor-infiltrating lymphocytes (TILs), and genetically engineered T-lymphocytes such as chimeric antigen receptor (CAR) T cells. Among these, CAR T cell therapy has recently made promising strides towards the treatment of advanced hematological and solid cancers. Although CAR T cell therapy might offer new hope for melanoma patients, it is not without its shortcomings, which include off-target toxicity, and the emergence of resistance to therapy (e.g., due to antigen loss), leading to eventual relapse. The present review will not only describe the basic steps of melanoma metastasis, but also discuss how CAR T cells could treat metastatic melanoma. We will outline specific strategies including combination approaches that could be used to overcome some limitations of CAR T cell therapy for metastatic melanoma.

Exploring the Role of Phytochemicals as Potent Natural Photosensitizers in Photodynamic Therapy

BACKGROUND

Cancer is still considered a deadly disease worldwide due to difficulties in diagnosis, painful treatment procedures, costly therapies, side effects, and cancer relapse. Cancer treatments using conventional methods like chemotherapy and radiotherapy were not convincing due to its post-treatment toxicity in the host. In Photodynamic Therapy (PDT), three individual non-toxic components including a photosensitizer, light source and oxygen cause damage to the cells and tissues when they are combined.

OBJECTIVE

In recent years, phytochemicals are being increasingly recognized as potent complementary drugs for cancer because of its natural availability, less toxicity and therapeutic efficiency in par with commercial drugs. Hence, the idea of using phytochemicals as natural photosensitizers in PDT resulted in a multiple pool of research studies with promising results in preclinical and clinical investigations.

METHODS

In this review, the potential of phytochemicals to act as natural photosensitizers for PDT, their mode of action, drawbacks, challenges and possible solutions are discussed in detail.

RESULTS

In PDT, natural photosensitizers, when used alone or in combination with other photosensitizers, induced cell death by apoptosis and necrosis, increased oxidative stress, altered cancer cell death signaling pathways, increased cytotoxicity and DNA damage in cancer cells. The pro-oxidant nature of certain antioxidant polyphenols, hormesis phenomenon, Warburg effect and DNA damaging potential plays a significant role in the photosensitizing mechanism of phytochemicals in PDT.

CONCLUSION

This review explores the role of phytochemicals that can act as photosensitizers alone or in combination with PDT and its mechanism of action on different cancers.

Extraction of chlorophyll and carotenoids loaded into chitosan as potential targeted therapy and bio imaging agents for breast carcinoma

In the current study, the treatment efficacy of ECHCAH was evaluated in vitro studies using cell viability and flow cytometry in human TNBCs. The results here showed significant gradual reduction in growth of TNBCs (MDA-231cell lines) after their exposure to serial concentrations for hydrogel assembly (5 μg/mL to 25 μg/mL) for 24 and 48 h, representing (86 ± 1% to 45 ± 1.5% p < 0.001) and (79 ± 1.5% to 35 ± 2.5% p < 0.001) respectively. The flow cytometry showed significant increase in the present of late apoptotic and necrotic cells (64% ± 1.2 and 27% ± 0.3 p < 0.001) after 48 h incubation compared to untreated cells (1.13% ± 0.3 and 4% ± 0.2 p < 0.001) respectively. It can be summarized that ECHCA inside targeted hydrogel assemblies can inhibit proliferation of cancer cells.

Nanoparticle-mediated tumor vaccines for personalized therapy: preparing tumor antigens in vivo or ex vivo?

Tumor vaccines, focusing on tailoring individual tumor antigens, have gained much attention in personalized tumor therapy. Recently, breakthroughs have been made in the development of tumor vaccines thanks to the progress in nanotechnology. We will summarize nanoparticle-mediated tumor vaccines for personalized therapy in this review. ROS/heat generating nanoparticles and molecules could induce immunogenic cell death and tumor antigen release in vivo. This strategy often includes chemotherapy, radiotherapy, photodynamic therapy, photothermal therapy, magneto-thermal therapy, etc. On the other hand, ex vivo technologies have been applied for processing of tumor cells/tissues to form effective tumor antigens, in which nanotechnology has shown very good prospects in delivering tumor antigens. In in vivo and ex vivo strategies, nanotechnology also could improve the immune effect through enhancing the uptake by targeting cells, reducing therapeutic drugs/agents, further encapsulating immuno-modulatory molecules or combining with other therapy treatments. Thus, therapeutic vaccines based on nanoparticles have the potential to enhance the immune response and reduce the side effects.

The Photosensitizing Efficacy of Micelles Containing a Porphyrinic Photosensitizer and KI against Resistant Melanoma Cells

Photodynamic therapy (PDT) is a promising alternative to overcome the resistance of melanoma to conventional therapies. Currently applied photosensitizers (PS) are often based on tetrapyrrolic macrocycles like porphyrins. Unfortunately, in some cases the use of this type of derivative is limited due to their poor solubility in the biological environment. Feasible approaches to surpass this drawback are based on lipid formulations. Besides that, and inspired in the efficacy of potassium iodide (KI) for antimicrobial photodynamic therapy (aPDT), the combined effect of singlet oxygen (1 O2 ) with KI was assessed in this work, as an alternative strategy to potentiate the effect of PDT against resistant melanoma cells.

The role of FOS-mediated autophagy activation in the indocyanine green-based photodynamic therapy for treating melanoma

The morbidity and mortality of melanoma which accounts for 90% of cutaneous neoplasm-related deaths is growing over the last few decades. Common treatments for melanoma are limited to poor tissue selectivity, high toxicity and drug resistance. Photodynamic therapy (PDT) is an effective adjuvant therapy and could be a promising therapy for melanoma. Multiple mechanisms are involved in PDT2 and programmed cell death (PCD) which comprises of autophagy and apoptosis is likely to be a critical one. Whereas, the molecular mechanism and subsequent effect of PDT-induced autophagy in melanoma are still unclear. In this study, we first analyzed gene expression data in the TCGA3 and GEO4 databases to clarify that PDT-induced-autophagy improved the prognosis of melanoma. The expression of FOS which generally defined as an immediate-early gene (IEG) and related to cell autophagy was found significantly elevated after PDT. To further investigate whether FOS played a key role in PDT-induced-autophagy of melanoma, we first determined the optimum concentration of ICG solution for autophagy observation. Then, relative FOS expression was detected at mRNA and protein level and cell autophagy was observed by western blot and flow cytometry. We found that ICG-PDT treatment could significantly elevate FOS expression in SKCM5 B16 cells, and FOS promoted ICG-PDT-induced cell autophagy. To sum up, our data indicated that FOS was involved in ICG-PDT-induced-autophagy in melanoma and furthermore improved the prognosis of melanoma.

Nanoparticles loading porphyrin sensitizers in improvement of photodynamic therapy for ovarian cancer

BACKGROUND

Ovarian cancer, the malignant tumor with the highest mortality rate in gynecological tumors, leads to a poor prognosis due to tumor metastasis. At present, the main treatment for ovarian cancer is the combination of cytoreduction surgery and chemotherapy. But the surgery is insufficient to solve the extensive transfer of tumor in the abdominal cavity and a large proportion of ovarian cancer cases have shown resistance to chemotherapy. Photodynamic therapy (PDT) is a viable treatment option for a wide range of applications, especially in malignant tumors. Porphyrin sensitizers, as the most widely used photosensitive agents, have the following advantages: short photosensitive period and high singlet oxygen production. However, most studies have found that it is difficult to achieve high loading rates of photosensitive agents, thus effective concentration in target tissue is suboptimal and the lethal ability is greatly reduced. In this article, we review several studies that nanoparticles loading porphyrin sensitizers for photodynamic therapy of ovarian cancer.

METHODS

We collected relevant literature from PUBMED and reviewed their research content.

RESULTS

The application of nanotechnology to PDT in ovarian cancer can reduce the non-specific toxicity of photosensitive agents and increase stability and delivery efficiency.

CONCLUSIONS

The combination with nanotechnology can cover the shortcomings of photodynamic therapy, but the specific efficacy still needs a large number of experiments to prove.

Nanotechnology in ovarian cancer: Diagnosis and treatment

To overcome the drawbacks of conventional delivery, this review spotlights a number of nanoscale drug delivery systems, including nanoparticles, liposomes, nano micelles, branched dendrimers, nanocapsules, and nanostructured lipid formulations for the targeted therapy of ovarian cancer. These nanoformulations offer numerous advantages to promote therapeutic drug delivery such as nontoxicity, biocompatibility, good biodegradability, increased therapeutic impact than free drugs, and non-inflammatory effects. Importantly, the development of specific ligands functionalized nanoformulations enable preferential targeting of ovarian tumors and eventually amplify the therapeutic potential compared to nonfunctionalized counterparts. Ovarian cancer is typically identified by biomarker assessment such as CA125, HE4, Mucin 1, and prostatic. There is, nevertheless, a tremendous demand for less costly, faster, and compact medical tools, both for timely detection and ovarian cancer control. This paper explored multiple types of tumor marker-based on nanomaterial biosensors. Initially, we mention different forms of ovarian cancer biomarkers involving CA125, human epididymis protein 4 (HE4), mucin 1 (MUC1), and prostate. It is accompanied by a brief description of new nanotechnology methods for diagnosis. Nanobiosensors for evaluating ovarian cancer biomarkers can be categorized based on electrochemical, optical, paper-based, giant magnetoresistive, and lab-on-a-chip devices.

pH-Responsive Nanostructures Based on Surface Active Fatty Acid-Protic Ionic Liquids for Imiquimod Delivery in Skin Cancer Topical Therapy

For topical treatment of skin cancer, the design of pH-responsive nanocarriers able to selectively release the drug in the tumor acidic microenvironment represents a reliable option for targeted delivery. In this context, a series of newly synthesized surface-active fatty acid-protic ionic liquids (FA-PILs), based on tetramethylguanidinium cation and different natural hydrophobic fatty acid carboxylates, have been investigated with the aim of developing a pH-sensitive nanostructured drug delivery system for cutaneous administration in the skin cancer therapy. The capability of FA-PILs to arrange in micelles when combined with each other and with the non-ionic surfactant d-α-Tocopherol polyethylene glycol succinate (vitamin E TPGS) as well as their ability to solubilize imiquimod, an immuno-stimulant drug used for the treatment of skin cancerous lesions, have been demonstrated. The FA-PILs-TPGS mixed micelles showed pH-sensitivity, suggesting that the acidic environment of cancer cells can trigger nanostructures’ swelling and collapse with consequent rapid release of imiquimod and drug cytotoxic potential enhancement. The in vitro permeation/penetration study showed that the micellar formulation produced effective imiquimod concentrations into the skin exposed to acid environment, representing a potential efficacious and selective drug delivery system able to trigger the drug release in the tumor tissues, at lower and less irritating drug concentrations.

Photodynamic therapy induces autophagy-mediated cell death in human colorectal cancer cells via activation of the ROS/JNK signaling pathway

Evidence has shown that m-THPC and verteporfin (VP) are promising sensitizers in photodynamic therapy (PDT). In addition, autophagy can act as a tumor suppressor or a tumor promoter depending on the photosensitizer (PS) and the cancer cell type. However, the role of autophagy in m-THPC- and VP-mediated PDT in in vitro and in vivo models of human colorectal cancer (CRC) has not been reported. In this study, m-THPC-PDT or VP-PDT exhibited significant phototoxicity, inhibited proliferation, and induced the generation of large amounts of reactive oxygen species (ROS) in CRC cells. From immunoblotting, fluorescence image analysis, and transmission electron microscopy, we found extensive autophagic activation induced by ROS in cells. In addition, m-THPC-PDT or VP-PDT treatment significantly induced apoptosis in CRC cells. Interestingly, the inhibition of m-THPC-PDT-induced autophagy by knockdown of ATG5 or ATG7 substantially inhibited the apoptosis of CRC cells. Moreover, m-THPC-PDT treatment inhibited tumorigenesis of subcutaneous HCT116 xenografts. Meanwhile, antioxidant treatment markedly inhibited autophagy and apoptosis induced by PDT in CRC cells by inactivating JNK signaling. In conclusion, inhibition of autophagy can remarkably alleviate PDT-mediated anticancer efficiency in CRC cells via inactivation of the ROS/JNK signaling pathway. Our study provides evidence for the therapeutic application of m-THPC and VP in CRC.

Recent Advances in Self-Exciting Photodynamic Therapy

Photodynamic therapy (PDT) is already (Food and Drug Administration) FDA approved and used in the clinic for oncological treatment of pancreatic, lung, esophagus, bile duct, and of course several cancers of skin. It is an important tool in the oncological array of treatments, but for it exist several shortcomings, the most prominent of which is the shallow depth penetration of light within tissues. One-way researchers have attempted to circumvent this is through the creation of self-exciting "auto-PDT" nanoplatforms, which do not require the presence of an external light source to drive the PDT process. Instead, these platforms are driven either through oxidative chemical excitation in the form of chemiluminescence or radiological excitation from beta-emitting isotopes in the form of Cherenkov luminescence. In both, electronic excitations are generated and then transferred to the photosensitizer (PS) via Resonance Energy Transfer (RET) or Cherenkov Radiation Energy Transfer (CRET). Self-driven PDT has many components, so in this review, using contemporary examples from literature, we will breakdown the important concepts, strategies, and rationale behind the design of these self-propagating PDT nanoplatforms and critically review the aspects which make them successful and different from conventional PDT. Particular focus is given to the mechanisms of excitation and the different methods of transfer of excited electronic energy to the photosensitizer as well as the resulting therapeutic effect. The papers reviewed herein will be critiqued for their apparent therapeutic efficiency, and a basic rationale will be developed for what qualities are necessary to constitute an "effective" auto-PDT platform. This review will take a biomaterial engineering approach to the review of the auto-PDT platforms and the intended audience includes researchers in the field looking for a new perspective on PDT nanoplatforms as well as other material scientists and engineers looking to understand the mechanisms and relations between different parts of the complex "auto-PDT" system.

Antibody-Based Immunotherapy: Alternative Approaches for the Treatment of Metastatic Melanoma

Melanoma is the least common form of skin cancer and is associated with the highest mortality. Where melanoma is mostly unresponsive to conventional therapies (e.g., chemotherapy), BRAF inhibitor treatment has shown improved therapeutic outcomes. Photodynamic therapy (PDT) relies on a light-activated compound to produce death-inducing amounts of reactive oxygen species (ROS). Their capacity to selectively accumulate in tumor cells has been confirmed in melanoma treatment with some encouraging results. However, this treatment approach has not reached clinical fruition for melanoma due to major limitations associated with the development of resistance and subsequent side effects. These adverse effects might be bypassed by immunotherapy in the form of antibody–drug conjugates (ADCs) relying on the ability of monoclonal antibodies (mAbs) to target specific tumor-associated antigens (TAAs) and to be used as carriers to specifically deliver cytotoxic warheads into corresponding tumor cells. Of late, the continued refinement of ADC therapeutic efficacy has given rise to photoimmunotherapy (PIT) (a light-sensitive compound conjugated to mAbs), which by virtue of requiring light activation only exerts its toxic effect on light-irradiated cells. As such, this review aims to highlight the potential clinical benefits of various armed antibody-based immunotherapies, including PDT, as alternative approaches for the treatment of metastatic melanoma.

Application of Nanomaterials in Biomedical Imaging and Cancer Therapy

Nanomaterials, such as nanoparticles, nanorods, nanosphere, nanoshells, and nanostars, are very commonly used in biomedical imaging and cancer therapy. They make excellent drug carriers, imaging contrast agents, photothermal agents, photoacoustic agents, and radiation dose enhancers, among other applications. Recent advances in nanotechnology have led to the use of nanomaterials in many areas of functional imaging, cancer therapy, and synergistic combinational platforms. This review will systematically explore various applications of nanomaterials in biomedical imaging and cancer therapy. The medical imaging modalities include magnetic resonance imaging, computed tomography, positron emission tomography, single photon emission computerized tomography, optical imaging, ultrasound, and photoacoustic imaging. Various cancer therapeutic methods will also be included, including photothermal therapy, photodynamic therapy, chemotherapy, and immunotherapy. This review also covers theranostics, which use the same agent in diagnosis and therapy. This includes recent advances in multimodality imaging, image-guided therapy, and combination therapy. We found that the continuous advances of synthesis and design of novel nanomaterials will enhance the future development of medical imaging and cancer therapy. However, more resources should be available to examine side effects and cell toxicity when using nanomaterials in humans.

Curcumin-silica nanocomplex preparation, hemoglobin and DNA interaction and photocytotoxicity against melanoma cancer cells

Melanoma is a malignant cancer of the skin associated with a high mortality. Early medical diagnosis and surgical intervention are essential for the treatment of melanoma. The use of plant-based compounds is an important strategy for the prevention and treatment of different types of cancers. Curcumin is a promising natural anticancer compound used towards treatment for various kinds of cancers. Studies have shown that curcumin could be applied as a photosensitizer in cancer photodynamic therapy (PDT). PDT uses light and a photosensitizing agent which produce reactive oxygen species leading to cancer cell death. The main obstacle for using curcumin as photosensitizer is its low solubilization ability in an aqueous environment. To improve its application in cancer treatment, we synthetized curcumin-silica nanoparticles as photosensitizer for photodynamic treatment of human melanoma cancer cells. Scanning electron microscopy, Transmission electron microscopy, Powder X-ray diffraction and Thermo geometric analysis indicated that curcumin was loaded on silica. The solubility of curcumin in water increased by using silica nanoparticles which wasconfirmed by spectroscopy results. The spectroscopy study confirmed the interaction of curcumin-silica nanocomplex with double strand DNA and no interaction with hemoglobin. The curcumin-silica nanocomplex and curcumin photodynamic effect was investigated on human melanoma cancer cells (A375) and also human fibroblast cells. The cell toxicity experiments showed that the curcumin-silica nanocomplex had greater photodynamic effects on cancer cell death as compared to free curcumin. The apoptotic assay by acridine orange/ethidium bromide (AO/EB) dual staining and colony forming ability confirmed the MTT results. Therefore, these results suggest that the curcumin-silica nanocomplex has great potential to be employed in photodynamic treatment of melanoma cancer.

Biological studies of an ICG-tagged aptamer as drug delivery system for malignant melanoma

Malignant melanoma accounts for about 1% of all skin malignant tumors and represents the most aggressive and lethal form of skin cancer. Clinically, there exist different therapeutic options for melanoma treatment, such as surgery, chemotherapy, radiotherapy, photodynamic therapy and immunotherapy. However, serious adverse effects usually arise, and survival rates are still low because a high number of patients present relapses within 6-9 months after therapy. AS1411 is a G-quadruplex (G4) aptamer capable of tumor-specific recognition, since it binds to nucleolin, a multi-functional protein expressed in many different types of cancer cells. In this work, we present a novel drug delivery system composed of AS1411 and indocyanine green (ICG) to track its accumulation in tumoral cells in a melanoma mouse model. Using a simple supramolecular strategy, we conjugated the complex AS1411-ICG with C₈ ligand, an acridine orange derivative with potential anticancer ligand. Then, we performed in vitro cytotoxicity experiments using the B16 mouse melanoma cell line, and in vivo experiments using a B16 mouse melanoma model to study biodistribution and histological changes. The circular dichroism (CD) data suggest that C₈ does not affect the parallel G4 topology of AS1411-ICG, whereas it increases its thermal stability. Incubation of B16 melanoma cells with the AS1411-ICG complex associated with C₈ increases the cytotoxicity compared with AS1411-ICG alone. From the in vivo studies, we conclude that both AS1411-ICG and AS1411-ICG-C₈ presented the potential to accumulate preferentially in tumor tissues. Moreover, these compounds seem to be efficiently removed from the mice's bodies through kidney clearance. In summary, these results suggest that these complexes derived from AS1411 aptamer could act as a delivery system of ligands with antitumoral activity for in vivo melanoma therapy.

Effective Photodynamic Therapy for Colon Cancer Cells Using Chlorin e6 Coated Hyaluronic Acid-Based Carbon Nanotubes

Colon cancer is the third major cancer contributor to mortality worldwide. Nanosized particles have attracted attention due to their possible contribution towards cancer treatment and diagnosis. Photodynamic therapy (PDT) is a cancer therapeutic modality that involves a light source, a photosensitizer and reactive oxygen species. Carbon nanotubes are fascinating nanocarriers for drug delivery, cancer diagnosis and numerous potential applications due to their unique physicochemical properties. In this study, single walled carbon nanotubes (SWCNTs) were coupled with hyaluronic acid (HA) and chlorin e6 (Ce6) coated on the walls of SWCNTs. The newly synthesized nanobiocomposite was characterized using ultraviolet-visible spectroscopy, Fourier transform electron microscopy (FTIR), X-ray diffraction analysis (XRD), particle size analysis and zeta potential. The loading efficiency of the SWCNTs-HA for Ce6 was calculated. The toxicity of the nanobiocomposite was tested on colon cancer cells using PDT at a fluence of 5 J/cm² and 10 J/cm². After 24 h, cellular changes were observed via microscopy, LDH cytotoxicity assay and cell death induction using annexin propidium iodide. The results showed that the newly synthesized nanobiocomposite enhanced the ability of PDT to be a photosensitizer carrier and induced cell death in colon cancer cells.

Engineering and biological assessment of double core nanoplatform for co-delivery of hybrid fluorophores to human melanoma

We investigated new development in photodynamic therapy (PDT), aiming at enhanced tumor selectivity and biocompatibility, which included application of a third-generation photosensitizing agent, i.e. xanthene-origin Rose Bengal (RB) co-encapsulated with up-converting NaYF₄ nanoparticles (NPs) co-doped with lanthanide ions: Er³⁺ (2%) and Yb³⁺ (20%). The hybrid fluorophores were applied as components of double core nanocarriers (NCs) obtained by double (multiple) emulsion solvent evaporation process. Next, to improve the biocompatibility and photodynamic activity, biodegradable polymer: poly(lactide-co-glycolide) - PLGA and non-ionic surfactants with different hydrophobicity: Span 80 and Cremophor A25, were used. After the engineering process, controlled by dynamic light scattering (DLS) measurements, ζ-potential evaluation, transmission electron and atomic force microscopy (TEM and AFM) imaging, as well as optical analysis provided by measurements of the up-conversion emission spectra and luminescence kinetics for encapsulated only NaYF₄:Er³⁺,Yb³⁺ NPs and co-encapsulated RB + NaYF₄:Er³⁺,Yb³⁺ molecules, spherical polyester NCs with average size <200 nm, were tested on human melanoma (Me-45 and MeWo) cells and a control human keratinocyte (HaCaT) cell line. The photodynamic action of the investigated NCs was assessed by oxidoreductive potential measurements with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, that corresponds to percentage of the viable cells. Immunofluorescence and the NCs internalization studies were visualized by confocal laser scanning microscopy (CLSM studies). Our results indicated effective photosensitizer delivery into the cancer cells and significant photodynamic efficiency enhanced by the near infrared (NIR)-activation of the encapsulated hybrid cargo in the skin melanoma cells.

Photochemical Internalization for Intracellular Drug Delivery. From Basic Mechanisms to Clinical Research

Photochemical internalisation (PCI) is a unique intervention which involves the release of endocytosed macromolecules into the cytoplasmic matrix. PCI is based on the use of photosensitizers placed in endocytic vesicles that, following light activation, lead to rupture of the endocytic vesicles and the release of the macromolecules into the cytoplasmic matrix. This technology has been shown to improve the biological activity of a number of macromolecules that do not readily penetrate the plasma membrane, including type I ribosome-inactivating proteins (RIPs), gene-encoding plasmids, adenovirus and oligonucleotides and certain chemotherapeutics, such as bleomycin. This new intervention has also been found appealing for intracellular delivery of drugs incorporated into nanocarriers and for cancer vaccination. PCI is currently being evaluated in clinical trials. Data from the first-in-human phase I clinical trial as well as an update on the development of the PCI technology towards clinical practice is presented here.

Near-Infrared Laser-Triggered, Self-Immolative Smart Polymersomes for in vivo Cancer Therapy

Purpose

Traditional chemotherapy is accompanied by significant side effects, which, in many aspects, limits its treatment efficacy and clinical applications. Herein, we report an oxidative responsive polymersome nanosystem mediated by near infrared (NIR) light which exhibited the combination effect of photodynamic therapy (PDT) and chemotherapy.

Methods

In our study, poly (propylene sulfide)₂₀-bl-poly (ethylene glycol)₁₂ (PPS₂₀-b-PEG₁₂) block copolymer was synthesized and employed to prepare the polymersome. The hydrophobic photosensitizer zinc phthalocyanine (ZnPc) was loaded in the shell and the hydrophilic doxorubicin hydrochloride (DOX·HCl) in the inner aqueous space of the polymersome.

Results

Under the irradiation of 660 nm NIR light, singlet oxygen ¹O₂ molecules were generated from ZnPc to oxidize the neighbouring sulfur atoms on the PPS block which eventually ruptured the intact structure of polymersomes, leading to the release of encapsulated DOX·HCl. The released DOX and the ¹O₂ could achieve a combination effect for cancer therapy if the laser activation and drug release occur at the tumoral sites. In vitro studies confirmed the generation of singlet oxygen and DOX release by NIR irradiation. In vivo studies showed that such a combined PDT-chemotherapy nanosystem could accumulate in A375 tumors efficiently, thus leading to significant inhibition on tumor growth as compared to PDT (PZ group) or chemotherapy alone (DOX group).

Conclusion

In summary, this oxidation-sensitive nanosystem showed excellent anti-tumor effects by synergistic chemophotodynamic therapy, indicating that this novel drug delivery strategy could potentially provide a new means for cancer treatments in clinic.

Nanosystems for Improved Targeted Therapies in Melanoma

Melanoma is one of the most aggressive forms of skin cancer, with limited therapeutic options. Since its incidence has been rapidly rising in recent years, the study of new targeted therapeutic strategies has increased. The implication of nanoscience in the development of alternative targeted therapies for melanoma has multiple benefits and could significantly improve the outcome of melanoma patients. In this paper, we review the most recent progress in the field of targeted therapies, emphasizing the impact of nanoscale materials on the targeting and controlled release of anti-tumor drugs. The applications of nanomedicine in the management of melanoma are extensive and refer to sentinel lymph node mapping, chemotherapy, and RNA interference; each of these applications harboring the potential to develop efficient and personalized diagnostic techniques and therapies. Further research, especially in clinical trials, is needed to establish whether fighting melanoma on the nanoscale level represents the key to reaching a critical inflection point in mankind’s battle with metastatic melanoma.

Verteporfin-Loaded Lipid Nanoparticles Improve Ovarian Cancer Photodynamic Therapy In Vitro and In Vivo

Advanced ovarian cancer is the most lethal gynecological cancer, with a high rate of chemoresistance and relapse. Photodynamic therapy offers new prospects for ovarian cancer treatment, but current photosensitizers lack tumor specificity, resulting in low efficacy and significant side-effects. In the present work, the clinically approved photosensitizer verteporfin was encapsulated within nanostructured lipid carriers (NLC) for targeted photodynamic therapy of ovarian cancer. Cellular uptake and phototoxicity of free verteporfin and NLC-verteporfin were studied in vitro in human ovarian cancer cell lines cultured in 2D and 3D-spheroids, and biodistribution and photodynamic therapy were evaluated in vivo in mice. Both molecules were internalized in ovarian cancer cells and strongly inhibited tumor cells viability when exposed to laser light only. In vivo biodistribution and pharmacokinetic studies evidenced a long circulation time of NLC associated with efficient tumor uptake. Administration of 2 mg.kg^-1 free verteporfin induced severe phototoxic adverse effects leading to the death of 5 out of 8 mice. In contrast, laser light exposure of tumors after intravenous administration of NLC-verteporfin (8 mg.kg^-1) significantly inhibited tumor growth without visible toxicity. NLC-verteporfin thus led to efficient verteporfin vectorization to the tumor site and protection from side-effects, providing promising therapeutic prospects for photodynamic therapy of cancer.

Targeted photodynamic therapy treatment of in vitro A375 metastatic melanoma cells

Metastatic Melanoma (MM) is a deadly form of skin cancer and many photodynamic therapy (PDT) studies have noted limitations in relation to effective photosensitizer (PS) drug uptake in tumors. The focus of this study was to develop a PS multicomponent nanoparticle drug conjugate carrier system which specifically targets MM cells via biomarkers to actively enhance PS delivery and so improve MM PDT. An antibody-metallated phthalocyanine-polyethylene glycol-gold nanoparticle drug conjugate, was successfully synthesized and characterized. PS active drug targeting PDT experiments at 673 nm were conducted within in vitro cultured MM. Results noted that this drug conjugate enhanced the PDT treatment of MM, through improved subcellular localization of the PS, as well as noted significantly improved cytotoxic and late apoptotic cellular death in cells. The results from this study demonstrate that through the bio-active antibody PS drug targeting of MM, the efficacy of PDT treatment for this cancer can be enhanced.

Simultaneous Photodiagnosis and Photodynamic Treatment of Metastatic Melanoma

Metastatic melanoma (MM) has a poor prognosis and is attributed to late diagnoses only when metastases has already occurred. Thus, early diagnosis is crucial to improve its overall treatment efficacy. The standard diagnostic tools for MM are incisional biopsies and/or fine needle aspiration biopsies, while standard treatments involve surgery, chemotherapy, or irradiation therapy. The combination of photodynamic diagnosis (PDD) and therapy (PDT) utilizes a photosensitizer (PS) that, when excited by light of a low wavelength, can be used for fluorescent non-destructive diagnosis. However, when the same PS is activated at a higher wavelength of light, it can be cytotoxic and induce tumor destruction. This paper focuses on PS drugs that have been used for PDD as well as PDT treatment of MM. Furthermore, it emphasizes the need for continued investigation into enhanced PS delivery via active biomarkers and passive nanoparticle systems. This should improve PS drug absorption in MM cells and increase effectiveness of combinative photodynamic methods for the enhanced diagnosis and treatment of MM can become a reality.

Enhancement of the stability of chlorophyll using chlorophyll-encapsulated polycaprolactone microparticles based on droplet microfluidics

Chlorophyll is a valuable bioactive compound, which is used as a natural food coloring agent and a photosensitizer for photodynamic therapy because of its antioxidant properties, antimutagenic ability, and near-infrared fluorescence. However, chlorophyll is unstable when it comes to retaining its antioxidant activity, when exposed to oxygen, high temperature, or light environments. To enhance the stability of chlorophyll, a polymer encapsulation method was proposed. Polycaprolactone (PCL) was employed to encapsulate the chlorophyll, and the particles size of the composites was controlled through droplet microfluidics. The composites (chlorophyll-encapsulated PCL particles) were characterized through UV-VIS spectrometry, SEM, optical microscopy, and light exposure. The particles were spherical, with diameters adjustable from 68 to 247 μm. Additionally, the chlorophyll-encapsulated PCL particles exhibited considerably prolonged chlorophyll stability. The solid microparticle is more convenient for storage and transportation, and have great potential for application in the food industry.

Functionalized photosensitive gelatin nanoparticles for drug delivery application

In this study, zinc phthalocyanine (ZnPc) was loaded onto gelatin nanoparticles functionalized with polyelectrolytes (polystyrene sulfonate/polyallylamine hydrochloride) by layer-by-layer (LbL) assembly. The process yield and the encapsulation efficiency were 76.0% ± 2.5 and 86.0% ± 1.8, respectively. The functionalized photosensitive gelatin nanoparticles (FPGN) had a mean diameter of 396.5 ± 45.8 nm, narrow distribution size with a polydispersity index of 0.106. The obvious switching of zeta potential indicates successful alternating deposition of the polyanion PSS and polycation PAH directly on the gelatin nanoparticles. The in vitro drug release investigation found that the LbL deposited polyelectrolyte bilayer is very efficient to reduce the release rate and assuage the initial burst for drugs loaded in gelatin nanoparticles. The photobiological activity of FPGN was evaluated on mouse macrophage carcinoma line J774 A-1. The cells viability decreased with the increase of the light dose in the range of 1-10.0 J.cm^-2. ZnPc-loaded in functionalized gelatin nanoparticles are the release systems that promise photodynamic therapy use.

Mitotic Catastrophe Induced in HeLa Tumor Cells by Photodynamic Therapy with Methyl-aminolevulinate

Photodynamic therapy (PDT) constitutes a cancer treatment modality based on the administration of a photosensitizer, which accumulates in tumor cells. The subsequent irradiation of the tumoral area triggers the formation of reactive oxygen species responsible for cancer cell death. One of the compounds approved in clinical practice is methyl-aminolevulinate (MAL), a protoporphyrin IX (PpIX) precursor intermediate of heme synthesis. We have identified the mitotic catastrophe (MC) process after MAL-PDT in HeLa human carcinoma cells. The fluorescence microscopy revealed that PpIX was located mainly at plasma membrane and lysosomes of HeLa cells, although some fluorescence was also detected at endoplasmic reticulum and Golgi apparatus. Cell blockage at metaphase-anaphase transition was observed 24 h after PDT by phase contrast microscopy and flow cytometry. Mitotic apparatus components evaluation by immunofluorescence and Western blot indicated: multipolar spindles and disorganized chromosomes in the equatorial plate accompanied with dispersion of centromeres and alterations in aurora kinase proteins. The mitotic blockage induced by MAL-PDT resembled that induced by two compounds used in chemotherapy, taxol and nocodazole, both targeting microtubules. The alterations in tumoral cells provided evidence of MC induced by MAL-PDT, resolving mainly by apoptosis, directly or through the formation of multinucleate cells.

Utilisation of Targeted Nanoparticle Photosensitiser Drug Delivery Systems for the Enhancement of Photodynamic Therapy

The cancer incidence world-wide has caused an increase in the demand for effective forms of treatment. One unconventional form of treatment for cancer is photodynamic therapy (PDT). PDT has 3 fundamental factors, namely a photosensitiser (PS) drug, light and oxygen. When a PS drug is administered to a patient, it can either passively or actively accumulate within a tumour site and once exposed to a specific wavelength of light, it is excited to produce reactive oxygen species (ROS), resulting in tumour destruction. However, the efficacy of ROS generation for tumour damage is highly dependent on the uptake of the PS in tumour cells. Thus, PS selective/targeted uptake and delivery in tumour cells is a crucial factor in PDT cancer drug absorption studies. Generally, within non-targeted drug delivery mechanisms, only minor amounts of PS are able to passively accumulate in tumour sites (due to the enhanced permeability and retention (EPR) effect) and the remainder distributes into healthy tissues, causing unwanted side effects and poor treatment prognosis. Thus, to improve the efficacy of PDT cancer treatment, research is currently focused on the development of specific receptor-based PS-nanocarrier platform drugs, which promote the active uptake and absorption of PS drugs in tumour sites only, avoiding unwanted side effects, as well as treatment enhancement. Therefore, the aim of this review paper is to focus on current actively targeted or passively delivered PS nanoparticle drug delivery systems, that have been previously investigated for the PDT treatment of cancer and so to deduce their overall efficacy and recent advancements.