FosPeg® PDT alters the EBV miRNAs and LMP1 protein expression in EBV positive nasopharyngeal carcinoma cells

Review of three-dimensional spheroid culture models of gynecological cancers for photodynamic therapy research

Photodynamic therapy (PDT) is a specific cancer treatment with minimal side effects. However, it remains challenging to apply PDT clinically, partially due to the difficulty of translating research findings to clinical settings as the conventional 2D cell models used for in vitro research are accepted as less physiologically relevant to a solid tumour. 3D spheroids offer a better model for testing PDT mechanisms and efficacy, particularly on photosensitizer uptake, cellular and subcellular distribution and interaction with cellular oxygen consumption. 3D spheroids are usually generated by scaffold-free and scaffold-based methods and are accepted as physiologically relevant models for PDT anticancer research. Scaffold-free methods offer researchers advantages including high efficiency, reproducible, and controlled microenvironment. While the scaffold-based methods offer an extracellular matrix-like 3D scaffold with the necessary architecture and chemical mediators to support the spheroid formation, the natural scaffold used may limit its usage because of low reproducibility due to patch-to-patch variation. Many studies show that the 3D spheroids do offer advantages to gynceologcial cancer PDT investigation. This article will provide a review of the applications of 3D spheroid culture models for the PDT research of gynaecological cancers.

Photodynamic Therapy Can Modulate the Nasopharyngeal Carcinoma Microenvironment Infected with the Epstein-Barr Virus: A Systematic Review and Meta-Analysis

Nasopharyngeal carcinoma is a malignancy from epithelial cells predominantly associated with the Epstein-Barr virus (EBV) infection, and it is responsible for 140,000 deaths annually. There is a current need to develop new strategies to increase the efficacy of antineoplastic treatment and reduce side effects. Thus, the present study aimed to perform a systematic review and meta-analysis of the ability of photodynamic therapy (PDT) to modulate the tumor microenvironment and PDT efficacy in nasopharyngeal carcinoma treatment. The reviewers conducted all steps in the systematic review. PubMed, Science Direct, Scopus, Scielo, Lilacs, EMBASE, and the Cochrane library databases were searched. The OHAT was used to assess the risk of bias. Meta-analysis was performed with a random-effects model (α = 0.05). Nasopharyngeal carcinoma cells treated with PDT showed that IL-8, IL-1α, IL-1β, LC3BI, LC3BII, MMP2, and MMP9 levels were significantly higher than in groups that did not receive PDT. NF-ĸB, miR BART 1-5p, BART 16, and BART 17-5p levels were significantly lower in the PDT group than in the control group. Apoptosis levels and the viability of nasopharyngeal carcinoma cells (>70%) infected with EBV were effective after PDT. This treatment also increased LMP1 levels (0.28-0.50/p < 0.05) compared to the control group. PDT showed promising results for efficacy in killing nasopharyngeal carcinoma cells infected with EBV and modulating the tumor microenvironment. Further preclinical studies should be performed to validate these results.

Insights into intricacies of the Latent Membrane Protein-1 (LMP-1) in EBV-associated cancers

Numerous lymphomas, carcinomas, and other disorders have been associated with Epstein-Barr Virus (EBV) infection. EBV's carcinogenic potential can be correlated to latent membrane protein 1 (LMP1), which is essential for fibroblast and primary lymphocyte transformation. LMP1, a transmembrane protein with constitutive activity, belongs to the tumour necrosis factor receptor (TNFR) superfamily. LMP1 performs number of role in the life cycle of EBV and the pathogenesis by interfering with, reprogramming, and influencing a vast range of host cellular activities and functions that are getting well-known but still poorly understood. LMP1, pleiotropically perturbs, reprograms and balances a wide range of various processes of cell such as extracellular vesicles, epigenetics, ubiquitin machinery, metabolism, cell proliferation and survival, and also promotes oncogenic transformation, angiogenesis, anchorage-independent cell growth, metastasis and invasion, tumour microenvironment. By the help of various experiments, it is proven that EBV-encoded LMP1 activates multiple cell signalling pathways which affect antigen presentation, cell-cell interactions, chemokine and cytokine production. Therefore, it is assumed that LMP1 may perform majorly in EBV associated malignancies. For the development of novel techniques toward targeted therapeutic applications, it is essential to have a complete understanding of the LMP1 signalling landscape in order to identify potential targets. The focus of this review is on LMP1-interacting proteins and related signalling processes. We further discuss tactics for using the LMP1 protein as a potential therapeutic for cancers caused by the EBV.

Ophiopogonin B induces reactive oxygen species‑dependent apoptosis through the Hippo pathway in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a common malignant tumor in South China and is characterized by a high death rate. Ophiopogonin B (OP‑B) is a bioactive component of Radix Ophiopogon japonicus, which is frequently used in traditional Chinese medicine to treat cancer. The present study aimed to examine the anti‑cancer properties of OP‑B on NPC cells. Cell viability and cell proliferation were measured using MTT and EdU assays. Flow cytometry was used to measure cell apoptosis, reactive oxygen species and mitochondrial membrane potential. Western blotting was used to investigate the expression of apoptosis and Hippo signaling pathway proteins. OP‑B inhibited the proliferation of NPC cells by inducing apoptosis and disturbing the mitochondrial integrity. OP‑B enhanced ROS accumulation. In addition, OP‑B promoted the expression of mammalian STE20‑like kinase 1, large tumor suppressor 1 and phosphorylated yes‑associated protein (YAP) and suppressed the expression of YAP and transcriptional enhanced associate domain in NPC cells. OP‑B increased the expression of forkhead box transcription factor O1 in the nuclear fraction. In conclusion, OP‑B has therapeutic potential and feasibility in the development of novel YAP inhibitors for NPC.

Effect of Foslip® mediated photodynamic therapy on 5-fluorouracil resistant human colorectal cancer cells

Colorectal cancer (CRC) is the commonest cancer in Hong Kong and is often treated with 5-fluorouracil (5-FU). However the clinical application of 5-FU was limited by drug resistance in CRC. Photodynamic therapy (PDT) is a novel treatment combating CRC via the combination of photosensitizer, molecular oxygen and light activation. In this study, 5-FU resistant HT29 (HT29FU) was established and its susceptibility to Foslip® PDT tested. Effect of 5-FU to HT29 cells was measured via qPCR. Efficacy of Foslip® PDT on HT29 and HT29FU cells were measured via photosensitizer uptake, cellular localization, cytotoxicity, cell cycle distribution and signal proteins expression. 5-FU significantly induced ABCB1 mRNA expression in HT29 cells; whereas with a 24 fold increase in HT29FU cells. Both cells responded similarly to Foslip® PDT, with the inhibitory concentration IC₂₀, IC₅₀ and IC₇₀ achieved at 1 ng/mL, 2 ng/mL and 5 ng/mL with 2 J/cm² light activation respectively. Foslip® PDT triggered apoptosis and reduced JNK protein expression at IC₇₀ on both cells. Effect of Foslip® PDT on HT29 cells was independent to 5-FU resistance properties. Therefore, Foslip® PDT could be a potential treatment for 5-FU resistant cancer patients. Further investigations on the Foslip® PDT mediated molecular changes in HT29FU cells deserve to be explored.

Comparative study of FosPeg® photodynamic effect on nasopharyngeal carcinoma cells in 2D and 3D models

Photodynamic Therapy (PDT) offers an alternative option for the treatment of nasopharyngeal carcinoma (NPC). The utilization of 3-dimensional (3D) culture model might provide better understanding of PDT effects on NPC cells. The aim of this in vitro study was to compare PDT effect on NPC cells using 2D and 3D models. Two 3D culture models were established using liquid overlay method with agarose base (MCL) and hanging drop method (MCS). PDT was carried out using the combination of FosPeg® and 652 nm laser in 3D and conventional 2D models. The effects of 3D culture size and morphology on the uptake and distribution of sensitizer and gene expression were examined. Photocytotoxity, mode of cell death, and protein expression were compared for 2D and 3D models. Regular and irregular NPC spheroids were obtained from MCL and MCS methods, respectively. A significantly down-regulation of LMP1 mRNA were observed in MCL spheroid. The sensitizer uptake in 3D spheroids was half of 2D culture. More sensitizers were required to obtain IC₅₀ in 3D spheroids. Apoptosis, necrosis and autophagosomes were detected in PDT treated 2D and 3D cells. Different protein expression patterns were observed in 2D and 3D models. FosPeg® PDT is effective in killing NPC cells. MCL-derived 3D spheroid model is more suitable for the evaluation of PDT killing mechanisms.

miR-7112-3p targets PERK to regulate the endoplasmic reticulum stress pathway and apoptosis induced by photodynamic therapy in colorectal cancer CX-1 cells

BACKGROUND

Colorectal cancer (CRC) is the third most common malignant tumor worldwide. Photodynamic therapy (PDT) is an emerging modality for the treatment of solid tumors. Sinoporphyrin sodium (DVDMS) is a new photosensitizer with good therapeutic killing effects on cancer cells. Recent findings have shown that microRNAs play important roles in many biological processes. However, the functions of microRNAs in DVDMS-induced PDT remain largely unclear.

MATERIALS AND METHODS

Proteins involved in endoplasmic reticulum (ER) stress and apoptosis of CX-1 cells treated with DVDMS-PDT were examined by Western blotting and cell viability assays. 15 candidate miRNAs targeting RNA-dependent protein kinase-like ER kinase (PERK) were screened and verified using the TargetScan, miRWalk and miRDB databases. The downstream pathways of candidate miRNAs with high scores were studied by cell transfection, qRT-PCR, Western blotting and dual-luciferase reporter assays. The subcellular location of DVDMS was confirmed by laser confocal microscopy.

RESULTS

DVDMS-PDT induced apoptosis via elevated ER stress and activation of the PERK/ATF4/CHOP/caspase cascade pathway in CX-1 cells. The endoplasmic reticulum was involved in the subcellular accumulation of DVDMS in CX-1 cells. Dual-luciferase reporting experiment confirmed that a direct crosslinking between miR-7112-3p and PERK. In addition, miR-7112-3p was highly expressed in CRC tissues compared with peripheral tissues.

CONCLUSION

Our work showed that miR-7112-3p directly targeted PERK and further regulated PERK/ATF4/CHOP/caspase cascade pathway, resulting in enhanced apoptosis in CX-1 cells treated with DVDMS-PDT.

Trends and targets in antiviral phototherapy

Photodynamic therapy (PDT) is a well-established treatment option in the treatment of certain cancerous and pre-cancerous lesions. Though best-known for its application in tumor therapy, historically the photodynamic effect was first demonstrated against bacteria at the beginning of the 20^th century. Today, in light of spreading antibiotic resistance and the rise of new infections, this photodynamic inactivation (PDI) of microbes, such as bacteria, fungi, and viruses, is gaining considerable attention. This review focuses on the PDI of viruses as an alternative treatment in antiviral therapy, but also as a means of viral decontamination, covering mainly the literature of the last decade. The PDI of viruses shares the general action mechanism of photodynamic applications: the irradiation of a dye with light and the subsequent generation of reactive oxygen species (ROS) which are the effective phototoxic agents damaging virus targets by reacting with viral nucleic acids, lipids and proteins. Interestingly, a light-independent antiviral activity has also been found for some of these dyes. This review covers the compound classes employed in the PDI of viruses and their various areas of use. In the medical area, currently two fields stand out in which the PDI of viruses has found broader application: the purification of blood products and the treatment of human papilloma virus manifestations. However, the PDI of viruses has also found interest in such diverse areas as water and surface decontamination, and biosafety.

The Epstein-Barr virus LMP1 interactome: biological implications and therapeutic targets

The oncogenic potential of Epstein-Barr virus (EBV) is mostly attributed to latent membrane protein 1 (LMP1), which is essential and sufficient for transformation of fibroblast and primary lymphocytes. LMP1 expression results in the activation of multiple signaling cascades like NF-ΚB and MAP kinases that trigger cell survival and proliferative pathways. LMP1 specific signaling events are mediated through the recruitment of a number of interacting proteins to various signaling domains. Based on these properties, LMP1 is an attractive target to develop effective therapeutics to treat EBV-related malignancies. In this review, we focus on LMP1 interacting proteins, associated signaling events, and potential targets that could be exploited for therapeutic strategies.

Effect of FosPeg® mediated photoactivation on P-gp/ABCB1 protein expression in human nasopharyngeal carcinoma cells

Multidrug resistance (MDR) refers to the ability of cancer cells to develop cross resistance to a range of anticancer drugs which are structurally and functionally unrelated. P-glycoprotein (P-gp) is the best studied MDR phenotype in photodynamic therapy (PDT) treated cells. Our pervious study demonstrated that FosPeg® mediated PDT is effective to NPC cell line models. In this in vitro study, the expression of MDR1 gene and its product P-gp in undifferentiated, poorly differentiated and well differentiated human nasopharyngeal carcinoma (NPC) cells were investigated. The influence of P-gp efflux activities on photosensitizer FosPeg® was also examined. Regardless of the differentiation status, PDT tested NPC cell lines all expressed P-gp protein. Results indicated that FosPeg® photoactivation could heighten the expression of MDR1 gene and P-gp transporter protein in a dose dependent manner. Up to 2-fold increase of P-gp protein expression were seen in NPC cells after FosPeg® mediated PDT. Interestingly, our finding demonstrated that FosPeg® mediated PDT efficiency is independent to the MDR1 gene and P-gp protein expression in NPC cells. FosPeg® itself is not the substrate of P-gp transporter protein and no efflux of FosPeg® were observed in NPC cells. Therefore, the PDT efficiency would not be affected even though FosPeg® mediated PDT could induce MDR1 gene and P-gp protein expression in NPC cells. FosPeg® mediated PDT could be a potential therapeutic approach for MDR cancer patients.