MPPa-PDT suppresses breast tumor migration/invasion by inhibiting Akt-NF-κB-dependent MMP-9 expression via ROS

Development of Liposomes Loaded with Chloroaluminum Phthalocyanine for Application of Photodynamic Therapy in Breast Cancer

Chloraluminium phthalocyanine (ClAlPc) has potential therapeutic effect for the treatment of cancer; however, the molecule is lipophilic and may present self-aggregation which limits its clinical success. Thus, nanocarriers like liposomes can improve ClAlPc solubility, reduce off-site toxicity and increase circulation time. For this purpose, developing suitable liposomes requires the evaluation of different lipid compositions. Herein, we aimed to develop liposomes containing soy phosphatidylcholine (SPC), 1,2-distearoyl-sn-glycero- 3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPEPEG2000), cholesterol and oleic acid loaded with ClAlPc using the surface response methodology and the Box-Behnken design. Liposomes with particle size from 110.93 to 374.97 nm and PdI from 0.265 to 0.468 were obtained. The optimized formulation resulted in 69.09 % of ClAlPc encapsulated, with particle size and polydispersity index, respectively, at 153.20 nm and 0.309, providing stability and aggregation control. Atomic force microscopy revealed vesicles in a spherical or almost spherical shape, while the analyzes by Differential Scanning Calorimetry (DSC), Powder X-ray Diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) suggested that the drug was adequately incorporated into the lipid bilayer of liposomes, in its amorphous state or molecularly dispersed. In vitro studies conducted in breast cancer cells (4T1) showed that liposome improved phototoxicity compared to the ClAlPc solution. ClAlPc-loaded liposomes also enhanced the production of ROS 3-fold compared to the ClAlPc solution. Finally, confocal microscopy and flow cytometry demonstrated the ability of the liposomes to enter cells and deliver the fluorescent ClAlPc photosensitizer with dose and time-dependent effects. Thus, this work showed that Box-Behnken factorial design was an effective strategy for optimizing formulation development. The obtained ClAlPc liposomes can be applied for photodynamic therapy in breast cancer cells.

Targeting PERK-ATF4-P21 axis enhances the sensitivity of osteosarcoma HOS cells to Mppα-PDT

Osteosarcoma (OS) is the most prevalent type of malignant bone tumor in adolescents. The overall survival of OS patients has reached a plateau recently. Thus, there is an urgent need to develop approaches to improve the sensitivity of OS to therapies. Pyropheophorbide-α methyl ester-mediated photodynamic therapy (MPPα-PDT) is a new type of tumor therapy, and elucidating its mechanism is helpful to improve its anti-tumor efficacy. Here, we investigated how PERK signaling promotes the human OS (HOS) cell survival induced by MPPα-PDT, as overcoming this may enhance sensitivity to MPPα-PDT. We found that MPPα-PDT combined with PERK inhibitor GSK2656157 enhanced HOS cell apoptosis by suppressing autophagy and p21. Autophagy inhibition and p21 depletion enhanced cell death, indicating pro-survival effects in MPPα-PDT. Notably, p21 was found to be an effector of the PERK-Atf4 pathway, which could positively regulate autophagy mediated by MPPα-PDT. In conclusion, we found that the combination of MPPα-PDT and GSK2656157 enhanced apoptosis in HOS cells by inhibiting autophagy. Mechanistically, this autophagy is p21-dependent and can be suppressed by GSK2656157, thereby enhancing sensitivity to MPPα-PDT.

Novel PEGylated cholephytosomes for targeting fisetin to breast cancer: in vitro appraisal and in vivo antitumoral studies

Fisetin (FIS) is a multifunctional bioactive flavanol that has been recently exploited as anticancer drug against various cancers including breast cancer. However, its poor aqueous solubility has constrained its clinical application. In the current work, fisetin is complexed for the first time with soy phosphatidylcholine in the presence of cholesterol to form a novel biocompatible phytosomal system entitled "cholephytosomes." To improve fisetin antitumor activity against breast cancer, stearylamine bearing cationic cholephytosomes (mPHY) were prepared and furtherly modified with hyaluronic acid (HPHY) to allow their orientation to cancer cells through their surface exposed phosphatidylserine and CD-44 receptors, respectively. In vitro characterization studies revealed promising physicochemical properties of both modified vesicles (mPHY and HPHY) including excellent FIS complexation efficiency (˷100%), improved octanol/water solubility along with a sustained drug release over 24 h. In vitro cell line studies against MDA-MB-231 cell line showed about 10- and 3.5-fold inhibition in IC50 of modified vesicles compared with free drug and conventional drug-phospholipid complex, respectively. Preclinical studies revealed that both modified cholephytosomes (mPHY and HPHY) had comparable cytotoxicity that is significantly surpassing free drug cytotoxicity. TGF-β1and its non-canonical related signaling pathway; ERK1/2, NF-κB, and MMP-9 were involved in halting tumorigenesis. Thus, tailoring novel phytosomal nanosystems for FIS could open opportunity for its clinical utility against cancer.

Hematoporphyrin derivative photodynamic therapy induces apoptosis and suppresses the migration of human esophageal squamous cell carcinoma cells by regulating the PI3K/AKT/mTOR signaling pathway

Esophageal cancer is one of the most common cancer types in humans worldwide. Photodynamic therapy (PDT) is a promising therapeutic strategy for the treatment of cancer. However, its underlying mechanism needs to be studied thoroughly. The present study focused on the antitumor effect and underlying mechanism of the use of hematoporphyrin derivative (HpD)-PDT against human esophageal squamous cell carcinoma cells via regulation of the PI3K/AKT/mTOR signaling pathway. A Cell Counting Kit-8 assay was used to measure cell viability. Migration was evaluated using a wound healing assay. An annexin V-FITC/PI kit was used to determine cell apoptosis rates. Protein expression levels were analyzed via western blotting. Reverse transcription-quantitative PCR was used to detect gene expression levels. A 2',7'-dichlorodihydrofluorescein diacetate kit was chosen to evaluate intracellular reactive oxygen species levels via flow cytometry. Cell viability and migration were decreased in KYSE-150 cells after HpD-PDT treatment. Cellular apoptosis was induced after HpD-PDT treatment, and the same trend was observed for autophagy. Furthermore, the PI3K/AKT/mTOR signaling pathway was inhibited. The viability and migration of KYSE-150 cells were significantly inhibited, and apoptosis was induced more effectively following treatment with a combination of HpD-PDT and the PI3K inhibitor, a final concentration of 20 µM LY294002. In conclusion, HpD-PDT could suppress esophageal cancer cell viability, induce apoptosis and inhibit migration by downregulating the PI3K/AKT/mTOR signaling pathway. Combination of HpD-PDT with PI3K inhibitor (LY294002) could enhance the therapeutic efficacy compared with that demonstrated by HpD-PDT alone. Further studies on combination therapy are required to achieve improved clinical outcomes.

Cellular Localization of Selected Porphyrins and Their Effect on the In Vitro Motility of Human Colon Tumors and Normal Cells

Standard therapies for colorectal cancer cannot eliminate or sufficiently reduce the metastasis process. Photodynamic therapy (PDT) may be an alternative to minimizing this problem. Here, we examined the cellular localization of selected porphyrins and determined whether free-base and manganese (III) metallated porphyrins may limit colon cancer cells' (HT29) or normal colon epithelial cells' (CCD 841 CoTr) motility in vitro. White light irradiation was used to initiate the photodynamic effect. Porphyrin uptake by the cells was determined by porphyrin fluorescence measurements through the use of confocal microscopy. Free-base porphyrin was found in cells, where it initially localized at the edge of the cytoplasm and later in the perinuclear area. The concentrations of porphyrins had no effect on cancer cell migration but had a significant effect on normal cell motility. Due to the low concentrations of porphyrins used, no changes in F-actin filaments of the cellular cytoskeleton were detected. Signal transmission via connexons between neighbouring cells was limited to a maximum of 40 µm for HT29 and 30 µm for CCD 841 CoTr cells. The tested porphyrins differed in their activity against the tumor and normal cells' migration capacity. Depending on the porphyrin used and the type of cells, their migration changed in relation to the control sample. The use of white light may change the activity of the porphyrins relative to the migratory capacity of the cells. The aim of the present study was to analyse the intracellular localization of tested porphyrins and their influence on the mobility of cells after irradiation with harmless white light.

Synthesis and characterization of novel Schiff base-silicon (IV) phthalocyanine complex for photodynamic therapy of breast cancer cell lines

BACKGROUND

Photodynamic therapy is an alternative anticancer treatment approach that promises high therapeutic efficacy. In this study, it is aimed to investigate the PDT-mediated anticancer effects of newly synthesized silicon phthalocyanine (SiPc) molecules on MDA-MB-231, MCF-7 breast cancer cell lines, and non-tumorigenic MCF-10A breast cell line.

METHODS

Novel bromo substituted Schiff base (3a), its nitro homolog (3b), and their silicon complexes (SiPc-5a and SiPc-5b) were synthesized. Their proposed structures were confirmed by FT-IR, NMR, UV-vis and MS instrumental techniques. MDA-MB-231, MCF-7 and MCF-10A cells were illuminated at a light wavelength of 680 nm for 10 min, giving a total irradiation dose of 10 j/cm². MTT assay was used to determine the cytotoxic effects of SiPc-5a and SiPc-5b. Apoptotic cell death was analyzed using flow cytometry. Changes in the mitochondrial membrane potential were determined by TMRE staining. Intracellular ROS generation was observed microscopically using H₂DCFDA dye. Colony formation assay and in vitro scratch assay were performed to analyze the clonogenic activity and cell motility. Transwell migration and matrigel invasion analyzes were conducted to observe changes in the migration and invasion status of the cells.

RESULTS

The combination of SiPc-5a and SiPc-5b with PDT exhibited cytotoxic effects on cancer cells and triggered cell death. SiPc-5a/PDT and SiPc-5b/PDT decreased mitochondrial membrane potential and increased intracellular ROS production. Statistically significant changes were detected in cancer cells' colony-forming ability and motility. SiPc-5a/PDT and SiPc-5b/PDT reduced cancer cells' migration and invasion capacities.

CONCLUSION

The present study identifies PDT-mediated antiproliferative, apoptotic, and anti-migratory characteristics of novel SiPc molecules. The outcomes of this study emphasize the anticancer properties of these molecules and suggest that they may be evaluated as drug-candidate molecules for therapeutic purposes.

Self-intensified synergy of a versatile biomimetic nanozyme and doxorubicin on electrospun fibers to inhibit postsurgical tumor recurrence and metastasis

Tumor-positive resection margins after surgery can result in tumor recurrence and metastasis. Although adjuvant postoperative radiotherapy and chemotherapy have been adopted in clinical practice, they lack efficacy and result in unavoidable side effects. Herein, a self-intensified in-situ therapy approach using electrospun fibers loaded with a biomimetic nanozyme and doxorubicin (DOX) is developed. The fabricated PEG-coated zeolite imidazole framework-67 (PZIF67) is demonstrated as a versatile nanozyme triggering reactions in cancer cells based on endogenous H₂O₂ and •O₂^-. The PZIF67-generated •OH induces reactive oxygen species (ROS) overload, implementing chemodynamic therapy (CDT). The O₂ produced by PZIF67 inhibits the expression of hypoxia-up-regulated proteins, thereby suppressing tumor progression. PZIF67 also catalyzes the degradation of glutathione, further disturbing the intracellular redox homeostasis and enhancing CDT. Furthermore, the introduced DOX not only kills cancer cells individually, but also replenishes the continuously consumed substrates for PZIF67-catalyzed reactions. The PZIF67-weakened drug resistance strengthens the cytotoxicity of DOX. The combined application of PZIF67 and DOX also suppresses metastasis-associated genes. Both in vitro and in vivo results demonstrate that the self-intensified synergy of PZIF67 and DOX on electrospun fibers efficiently prevents postsurgical tumor recurrence and metastasis, offering a feasible therapeutic regimen for operable malignant tumors.

5-ALA mediated photodynamic therapy with combined treatment improves anti-tumor efficacy of immunotherapy through boosting immunogenic cell death

Photodynamic therapy (PDT) is clinically promising in destructing primary tumors and immunotherapy awakes host immunity to control distant metastases. 5-aminolevulinic acid (5-ALA), a smart photosensitizer, converts into a physiological PDT agent with no dark toxicity in vivo. In this study, we found for the first time 5-ALA-PDT induced colorectal cancer (CRC) cells death by immunogenic cell death (ICD) upon AKT inhibition. Dying cancer cells induced by 5-ALA-PDT efficiently activated bone-marrow derived dendritic cells (BMDCs). Simultaneously, autophagy was observed after AKT inhibition by 5-ALA-PDT. Besides, we found cells died more remarkable by ICD under a circumstance of low occurrence of autophagy. To evaluate the effects of 5-ALA-PDT in vivo, we applied subcutaneous tumor mouse model and delightedly found 5-ALA-PDT induced a systemic antitumor immune response to control both primary tumors and distant metastases. Meanwhile, 5-ALA-PDT enhanced Th1 immunity, leading cytotoxic T lymphocyte response, and raised tumor-specific T cells. Combining with Chloroquine (CQ), 5-ALA-PDT further augmented tumor-specific immunity effects indicating protective role of autophagy. Together, the combination therapy of 5-ALA-PDT and autophagy inhibitor synergistically led to a novel clinical approach and potential ICD-based tumor vaccine for CRC patients.

Tumor-promoting properties of enolase-phosphatase 1 in breast cancer via activating the NF-κB signaling pathway

BACKGROUND

Evidence suggests that enolase-phosphatase 1 (ENOPH1) is involved in the progression of some certain types of cancers and acts as an oncogenic factor in tumor progression. The present study aimed to identify the central role of ENOPH1 in the progression of breast cancer (BC), a highly proliferative and aggressive disease.

METHODS AND RESULTS

ENOPH1 expression in BC tissues was explored based on the online resource and 40 paired fresh BC and para-carcinoma samples. Functional assays were performed to evaluate the biological effect of ENOPH1 on cell proliferation and migration in ENOPH1-silenced or overexpressing BC cell lines. Blockade of NF-κB by BAY11-7082 was performed to evaluate whether ENOPH1 exerted tumor-promoting properties via regulating the NF-κB signaling pathway. Results of the present study demonstrated that ENOPH1 expression was profoundly upregulated in BC tissues compared with adjacent breast tissues, and ENOPH1 expression was associated with cancer stage, node metastasis status, and overall survival. Functional assays demonstrated that ENOPH1 overexpression significantly accelerated BC cell proliferation, migration, and invasion, while genetic knockdown of ENOPH1 yielded the opposite effects. Mechanistically, ENOPH1 activated the NF-κB pathway, as evidenced by increased expression of NF-κB downstream genes and enhanced NF-κB p65 nuclear translocation. Furthermore, the oncogenic properties of ENOPH1 in proliferation, migration, and invasion were restrained following inhibition of the NF-κB signaling pathway.

CONCLUSIONS

These findings indicated the significance of ENOPH1 in promoting cell proliferation and invasion, mainly through activating the NF-κB pathway, suggesting that ENOPH1 might be an attractive prognostic factor and a potential target for BC therapy.

The initiation of oxidative stress and therapeutic strategies in wound healing

When the production of reactive oxygen species (ROS) is overloaded surpassing the capacity of the reductive rheostat, mammalian cells undergo a series of oxidative damage termed oxidative stress (OS). This phenomenon is ubiquitously detected in many human pathological conditions. Wound healing program implicates continuous neovascularization, cell proliferation, and wound remodeling. Increasing evidence indicates that reactive oxygen species (ROS) have profound impacts on the wound healing process through regulating a series of the physiological and pathological program including inflammatory response, cell proliferation, angiogenesis, granulation as well as extracellular matrix formation. In most pathological wound healing processes, excessive ROS exerts a negative role on the wound healing process. Interestingly, the moderate increase of ROS levels is beneficial in killing bacteria at the wound site, which creates a sterile niche for revascularization. In this review, we discussed the physiological rhythms of wound healing and the role of ROS in this progress, aim to explore the potential manipulation of OS as a promising therapeutic avenue.

Free and Poly-Methyl-Methacrylate-Bounded BODIPYs: Photodynamic and Antimigratory Effects in 2D and 3D Cancer Models

Several limitations, including dark toxicity, reduced tumor tissue selectivity, low photostability and poor biocompatibility hamper the clinical use of Photodynamic therapy (PDT) in cancer treatment. To overcome these limitations, new PSs have been synthetized, and often combined with drug delivery systems, to improve selectivity and reduce toxicity. In this context, BODIPYs (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) have recently emerged as promising and easy-to-handle scaffolds for the preparation of effective PDT antitumor agents. In this study, the anticancer photodynamic effect of newly prepared negatively charged polymethyl methacrylate (nPMMA)-bounded BODIPYs (3@nPMMA and 6@nPMMA) was evaluated on a panel of 2D- and 3D-cultured cancer cell lines and compared with free BODIPYs. In particular, the effect on cell viability was evaluated, along with their ability to accumulate into the cells, induce apoptotic and/or necrotic cell death, and inhibit cellular migration. Our results indicated that 3@nPMMA and 6@nPMMA reduce cancer cell viability in 3D models of HC116 and MCF7 cells more effectively than the corresponding free compounds. Importantly, we demonstrated that MDA-MB231 and SKOV3 cell migration ability was significantly impaired by the PDT treatment mediated by 3@nPMMA and 6@nPMMA nanoparticles, likely indicating the capability of this approach to reduce metastatic tumor potential.

Combined Photodynamic and Photothermal Therapy and Immunotherapy for Cancer Treatment: A Review

Photoactivation therapy based on photodynamic therapy (PDT) and photothermal therapy (PTT) has been identified as a tumour ablation modality for numerous cancer indications, with photosensitisers and photothermal conversion agents playing important roles in the phototherapy process, especially in recent decades. In addition, the iteration of nanotechnology has strongly promoted the development of phototherapy in tumour treatment. PDT can increase the sensitivity of tumour cells to PTT by interfering with the tumour microenvironment, whereas the heat generated by PTT can increase blood flow, improve oxygen supply and enhance the PDT therapeutic effect. In addition, tumour cell debris generated by phototherapy can serve as tumour-associated antigens, evoking antitumor immune responses. In this review, the research progress of phototherapy, and its research effects in combination with immunotherapy on the treatment of tumours are mainly outlined, and issues that may need continued attention in the future are raised.

A novel 450-nm laser-mediated sinoporphyrin sodium-based photodynamic therapy induces autophagic cell death in gastric cancer through regulation of the ROS/PI3K/Akt/mTOR signaling pathway

BACKGROUND

Photodynamic therapy (PDT) has become an ideal and promising therapeutic method for fighting cancer, but its common application in clinical practice is prevented by the limitations of expensive devices in light sources and phototoxicity in photosensitizers. The aim of this study was to explore the antitumor efficiency of the novel 450-nm blue laser (BL) combined with sinoporphyrin sodium (DVDMS)-mediated PDT against human gastric cancer (GC) in vitro and in vivo, focusing on autophagy pathway.

METHODS

Cell viability was detected by Cell Counting Kit-8 and colony formation assays in HGC27, MGC803, AGS, and GES-1 cells. Cell apoptosis was measured by flow cytometry and western blotting. The production of reactive oxygen species (ROS) was measured by fluorescence microscopy and flow cytometry. Autophagy was determined by transmission electron microscopy and western blotting. The antitumor effect of BL-PDT in vivo was detected by a subcutaneous tumor model in nude mice.

RESULTS

The novel 450-nm laser-mediated DVDMS-based PDT caused remarkable growth inhibition and apoptosis induction in GC cells in vitro by the production of excessive ROS. Autophagy flux was induced by BL-PDT in GC cells, as determined by LC3 conversion assay, LC3 turnover assay, and mRFP-GFP-LC3 puncta assay. Furthermore, autophagy induction was demonstrated to positively contribute to BL-PDT-induced apoptotic effects on GC cells. Mechanically, ROS/PI3K/Akt/mTOR pathway was identified to involve in the regulation of BL-PDT-induced autophagy as determined by transcriptomic analysis and functional studies. Consistently, xenograft studies confirmed the significant antitumor effect of BL-PDT and its favorable safety in vivo.

CONCLUSIONS

The novel 450-nm laser-mediated DVDMS-based PDT may be a safe and effective approach against GC. Our results thus provide compelling evidence for the therapeutic application of BL-PDT in human GC.

Increasing cancer permeability by photodynamic priming: from microenvironment to mechanotransduction signaling

The dense cancer microenvironment is a significant barrier that limits the penetration of anticancer agents, thereby restraining the efficacy of molecular and nanoscale cancer therapeutics. Developing new strategies to enhance the permeability of cancer tissues is of major interest to overcome treatment resistance. Nonetheless, early strategies based on small molecule inhibitors or matrix-degrading enzymes have led to disappointing clinical outcomes by causing increased chemotherapy toxicity and promoting disease progression. In recent years, photodynamic therapy (PDT) has emerged as a novel approach to increase the permeability of cancer tissues. By producing excessive amounts of reactive oxygen species selectively in the cancer microenvironment, PDT increases the accumulation, penetration depth, and efficacy of chemotherapeutics. Importantly, the increased cancer permeability has not been associated to increased metastasis formation. In this review, we provide novel insights into the mechanisms by which this effect, called photodynamic priming, can increase cancer permeability without promoting cell migration and dissemination. This review demonstrates that PDT oxidizes and degrades extracellular matrix proteins, reduces the capacity of cancer cells to adhere to the altered matrix, and interferes with mechanotransduction pathways that promote cancer cell migration and differentiation. Significant knowledge gaps are identified regarding the involvement of critical signaling pathways, and to which extent these events are influenced by the complicated PDT dosimetry. Addressing these knowledge gaps will be vital to further develop PDT as an adjuvant approach to improve cancer permeability, demonstrate the safety and efficacy of this priming approach, and render more cancer patients eligible to receive life-extending treatments.

Photodynamic therapy in breast cancer treatment

Breast cancer is a serious public problem in modern society. Photodynamic therapy (PDT) is increasingly used in modern medicine. Currently, PDT is an innovative method of treating breast cancer. Irreversible damage to neoplastic tissues is associated with the use of physicochemical processes. Generating cytotoxic reactive oxygen species [singlet oxygen (1O2)] is leading to tumor cell death. At the same time, valuable information can be extracted from breast cancer cells. Photogenerated 1O2 is the major factor responsible for cell necrosis during PDT. 1O2 can react rapidly intracellularly with all organic substances. The use of photodynamic therapy on tissues in vitro creates conditions for testing various types of solutions and implementing them in in vivo treatment. This article is a review of recent advances in PDT for treatment of breast cancer. PDT is a novel cancer diagnostic and cancer treatment therapy. Therefore, an understanding of the possibility to generate a toxic form of 1O2 is necessary. The knowledge gained from the basics of PDT in vitro can be useful in biomedical applications in vivo. The current literature mentions PDT in the treatment of cancers located very deep within the human body. Therefore, the development of agents used to deliver 1O2 to the deep cancerous tissue is a new challenge which can have an efficient impact on this discipline. This review covers the literature between 2000-2022.

Effects of 5-ALA mediated photodynamic therapy in oral cancer stem cells

The aim of the present study was to investigate the effects of PDT using the photosensitizer 5-aminoulevulinic acid (5-ALA) in oral squamous cell carcinoma (OSCC) behavior, mainly regarding its role on the cancer stem cell (CSC) phenotypes and in maintenance of the stem cell properties. Two OSCC cell lines were used and divided in the groups: Control, 5-ALA, LED 6 J/cm² and PDT. MTT and Neutral red assays were used to access cellular viability, cell migration was evaluated by the wound healing assay. The stem cell phenotype was analyzed by flow cytometry to evaluate the CD44^high/ESA^high, CD44^high/ESA^low and CD44^low populations, by the clonogenic and tumor sphere formation assays as well as by RT-qPCR. The presence of Protoporphyrin IX in each CSC fraction was evaluated by flow cytometry. The OSCC cell lines showed a significant decrease in cell viability and migration after PDT. The percentage of CD44^high/ESA^high cells decreased after PDT, which was associated with an increase in the CD44^low cells and with a functional decrease in the colony and sphere formation capacity. CD44^high/ESA^high cells showed increased PpIX, which contributed for their greater sensitivity to PDT. INV gene increased significantly after PDT, indicating cellular differentiation. Altogether, our results demonstrate that 5-ALA mediated PDT decreases not only the fraction of oral CSC but also their functional capabilities, inducing their differentiation.

Tribbles homolog 3 contributes to high glucose-induced injury in retinal pigment epithelial cells via binding to growth factor receptor-bound 2

Diabetic retinopathy (DR) is the most typical complication of diabetes, which severely threatens sight. Tribbles homolog 3 (TRB3), a kind of pseudokinase, is discovered to be highly expressed in diabetes and retinas after retinal detachment. TRB3 expression in human retinal pigment epithelial (hRPE) cells exposed to different concentrations of glucose was tested by RT-qPCR and western blot. Then, cells were induced with 30 mM high glucose (HG) to establish a DR cell model. Following TRB3 knockdown, cell viability estimation employed CCK-8 assay. The mRNA levels of inflammatory factors were detected by RT-qPCR. Reactive oxygen species (ROS) level was measured by DCFH-DA assay, and levels of oxidative stress markers were evaluated applying corresponding kits. Cell apoptosis was assayed by TUNEL assay and western blot. Following, the growth factor receptor-bound 2 (GRB2) expression was also examined by RT-qPCR and western blot. The interaction between TRB3 and GRB2 was verified by Co-IP assay. After GRB2 was overexpressed in HG-induced hRPE cells transfected with shRNA-TRB3, functional experiments were conducted again. The results manifested that TRB3 expression was elevated under HG conditions. Deficiency of TRB3 enhanced the viability while alleviated inflammation, oxidative stress, and apoptosis in HG-induced hRPE cells. GRB2 was also increased in HG-exposed hRPE cells. Moreover, GRB2 had a strong affinity with TRB3 and positively regulated by TRB3. After GRB2 overexpression, the effects of TRB3 knockdown on HG-stimulated hRPE cells were all reversed. Briefly, this study confirmed the promoting role of TRB3/GRB2 axis in the progression of DR.

Effects of Curcumin-mediated photodynamic therapy on autophagy and Epithelial-mesenchymal transition of lung cancer cells

BACKGROUND

This study aimed to investigated whether Curcumin-mediated PDT suppress EMT in lung cancer cells, and explore the roles of autophagy in the process of regulating EMT.

METHODS

Lung cancer cell viability was assessed by CCK-8 assay. The expression of epithelial marker and mesenchymal markers, the conversion of LC3-I to LC3-II and the levels of p62 and beclin1 in A549 and SPCA1 cells were measured by Western blotting assay. The Wound healing and Transwell assays were used to detect the migration and invasion abilities of the A549 and SPCA1 cells. Autophagosome formation was detected via observing the colocalization of Lamp-2 with LC3 in A549 cells, and the autophagy ultrastructure was observed by TEM.

RESULTS

Curcumin-PDT inhibited EMT, migration and invasion and induced autophagy in lung cancer cells. Curcumin-PDT induced autophagy was involved in the process of PDT inhibiting EMT, but it presented a promoting effect of EMT in lung cancer cells. Curcumin-PDT combined with CQ further inhibited EMT, invasion and migration of lung cancer cells.

CONCLUSIONS

The role of PDT-induced autophagy in the regulation of EMT was determined to be a promoting effect in lung cancer. Therefore, Curcumin-mediated PDT combined with autophagy inhibitor further suppressed EMT of lung cancer cells, and may represent a potential strategy against invasion and migration of lung cancer.

UBAP2L promotes gastric cancer metastasis by activating NF-κB through PI3K/AKT pathway

Ubiquitin-associated protein 2-like (UBAP2L) is highly expressed in various types of tumors and has been shown to participate in tumor growth and metastasis; however, its role in gastric cancer (GC) remains unknown. In this study, we observed that UBAP2L expression was markedly elevated in GC tissues and five GC cell lines. Higher expression of UBAP2L was associated with poor prognosis as revealed by bioinformatics analysis on online websites and laboratory experiments. Knockdown of UBAP2L impeded the migration and invasion abilities of GC cell lines. In contrast, its overexpression enhanced the migration and invasion abilities of GC cell lines. Overexpression of UBAP2L also increased the number and size of lung metastatic nodules in vivo. According to the results of mass spectrometry and pathway annotation of the identified proteins, the PI3K/AKT pathway was found to be related to UBAP2L regulation. Further exploration and rescue experiments revealed that UBAP2L stimulates the expression and nuclear aggregation of p65 and promotes the expression of SP1 by activating the PI3K/AKT pathway. In summary, our findings indicate that UBAP2L regulates GC metastasis through the PI3K/AKT/SP1/NF-κB axis. Thus, targeting UBAP2L may be a potential therapeutic strategy for GC.

The Role of Graphene Oxide Nanocarriers in Treating Gliomas

Gliomas are the most common primary malignant tumors of the central nervous system, and their conventional treatment involves maximal safe surgical resection combined with radiotherapy and temozolomide chemotherapy; however, this treatment does not meet the requirements of patients in terms of survival and quality of life. Graphene oxide (GO) has excellent physical and chemical properties and plays an important role in the treatment of gliomas mainly through four applications, viz. direct killing, drug delivery, immunotherapy, and phototherapy. This article reviews research on GO nanocarriers in the treatment of gliomas in recent years and also highlights new ideas for the treatment of these tumors.

Targeting X box-binding protein-1 (XBP1) enhances the sensitivity of HOS osteosarcoma cells to pyropheophorbide- α methyl ester-mediated photodynamic therapy

Photodynamic therapy (PDT), utilizes a photochemical reaction between photosensitizer and light to cause cancer death by generating reactive oxygen species (ROS). X-box binding protein 1 (XBP1), a downstream product of the IRE1α-XBP1 pathway, regulates diverse target genes, including various proto-oncogenes and its overexpression was closely related to the occurrence and progression of malignant tumors. The present study was performed to explore the role of XBP1 in human osteosarcoma HOS cells treated with pyropheophorbide-α methyl ester (MPPα)-mediated photodynamic therapy (PDT) (MPPα-PDT) and its potential mechanisms. The protein IRE1α and XBP1 increased with a time-dependent manner after MPPα-PDT treated, which indicated that MPPα-PDT induced the activation of the IRE1α-XBP1 pathway in HOS cells. Besides, MPPα-PDT treated alone or combined with XBP1 knockdown could both restrain the cell viability, but the latter one has more notable effect, which indicated that XBP1 knockdown may enhance the cell inhibitory effect by MPPα-PDT. Simultaneously, the apoptotic rate measured by flow cytometry (FCM) was increased surprisedly and the expression of apoptosis proteins was increased when knockdown XBP1 under the MPPα-PDT. In addition, antioxidant-related proteins such as the Catalase and SOD1 protein levels decreased, while the intracellular ROS content increased in HOS cells when knockdown XBP1 under the MPPα-PDT. These results suggested that the mechanism of XBP1 mediating resistance in HOS cells might be related to the expression of antioxidant molecules. In summary, this study found that the IRE1α-XBP1 pathway was activated in HOS cells after MPPα-PDT treated, and furthermore, XBP1 knockdown could decrease HOS cell viability through apoptosis and enhance the anti-tumor effect of MPPα-PDT remarkably in the meantime, which related to the regulation of oxidation-antioxidant system.

RhoA enhances osteosarcoma resistance to MPPa-PDT via the Hippo/YAP signaling pathway

Background

Osteosarcoma (OS) is the most prevalent primary bone malignancy affecting adolescents, yet the emergence of chemoradiotherapeutic resistance has limited efforts to cure affected patients to date. Pyropheophorbide-α methyl ester-mediated photodynamic therapy (MPPa-PDT) is a recently developed, minimally invasive treatment for OS that is similarly constrained by such therapeutic resistance. This study sought to explore the mechanistic basis for RhoA-activated YAP1 (YAP)-mediated resistance in OS.

Methods

The relationship between YAP expression levels and patient prognosis was analyzed, and YAP levels in OS cell lines were quantified. Immunofluorescent staining was used to assess YAP nuclear translocation. OS cell lines (HOS and MG63) in which RhoA and YAP were knocked down or overexpressed were generated using lentiviral vectors. CCK-8 assays were used to examine OS cell viability, while the apoptotic death of these cells was monitored via Hoechst staining, Western blotting, and flow cytometry. Tumor-bearing nude mice were additionally used to assess the relationship between lentivirus-mediated alterations in RhoA expression and MPPa-PDT treatment outcomes. TUNEL and immunohistochemical staining approaches were leveraged to assess apoptotic cell death in tissue samples.

Results

OS patients exhibited higher levels of YAP expression, and these were correlated with a poor prognosis. MPPa-PDT induced apoptosis in OS cells, and such MPPa-PDT-induced apoptosis was enhanced following YAP knockdown whereas it was suppressed by YAP overexpression. RhoA and YAP expression levels were positively correlated in OS patients, and both active and total RhoA protein levels rose in OS cells following MPPa-PDT treatment. When RhoA was knocked down, levels of unphosphorylated YAP and downstream target genes were significantly reduced, while RhoA/ROCK2/LIMK2 pathway phosphorylation was suppressed, whereas RhoA overexpression resulted in the opposite phenotype. MPPa-PDT treatment was linked to an increase in HMGCR protein levels, and the inhibition of RhoA or HMGCR was sufficient to suppress RhoA activity and to decrease the protein levels of YAP and its downstream targets. Mevalonate administration partially reversed these reductions in the expression of YAP and YAP target genes. RhoA knockdown significantly enhanced the apoptotic death of OS cells in vitro and in vivo following MPPa-PDT treatment, whereas RhoA overexpression had the opposite effect.

Conclusions

These results suggest that the mevalonate pathway activates RhoA, which in turn activates YAP and promotes OS cell resistance to MPPa-PDT therapy. Targeting the RhoA/ROCK2/LIMK2/YAP pathway can significantly improve the efficacy of MPPa-PDT treatment for OS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-021-00690-6.

DNA Hypermethylation Involves in the Down-Regulation of Chloride Intracellular Channel 4 (CLIC4) Induced by Photodynamic Therapy

The altered expression of chloride intracellular channel 4 (CLIC4) was reported to correlate with tumor progression. Previously, we have shown that the reduced cellular invasion induced by photodynamic therapy (PDT) is associated with suppression of CLIC4 expression in PDT-treated cells. Herein, we attempted to decipher the regulatory mechanisms involved in PDT-mediated CLIC4 suppression in A375 and MDA-MB-231 cells in vitro. We found that PDT can increase the expression and enzymatic activity of DNA methyltransferase 1 (DNMT1). Bisulfite sequencing PCR further revealed that PDT can induce hypermethylation in the CLIC4 promoter region. Silencing DNMT1 rescues the PDT-induced CLIC4 suppression and inhibits hypermethylation in its promoter. Furthermore, we found tumor suppressor p53 involves in the increased DNMT1 expression of PDT-treated cells. Finally, by comparing CLIC4 expression in lung malignant cells and normal lung fibroblasts, the extent of methylation in CLIC4 promoter was found to be inversely proportional to its expression. Taken together, our results indicate that CLIC4 suppression induced by PDT is modulated by DNMT1-mediated hypermethylation and depends on the status of p53, which provides a possible mechanistic basis for regulating CLIC4 expression in tumorigenesis.

The potential of photodynamic therapy in current breast cancer treatment methodologies

Photodynamic Therapy (PDT) has been known for over a hundred years, and currently gaining in acceptance as an alternative cancer treatment. Light delivery is still a difficult problem in deep cancer treatment with PDT. Only near-infrared light in the 700-1100 nm range can penetrate deeply into the tissue because most tissue chromophores, including oxyhemoglobin, deoxyhemoglobin, melanin and fat, poorly absorb in the near infrared window. The light sources used in PDT are lasers, arc lamps, light-emitting diodes and fluorescent lamps. PDT has been used for many different clinical applications. PDT may be excellent alternative in the treatment and diagnosis of breast cancer compared to the conventional surgery, chemotherapy and radiotherapy. The basic elements of PDT are an appropriate photosensitizer (PS), oxygen, and light. The effectiveness of photodynamic therapy depends on the induction of photocytotoxic reactions, which are the result of light activation of PS), pre-administered to the body. The condition for initiating PDT processes is light absorption by PS and subsequent localized generation of cytotoxic reactive oxygen species. This study is a review of empirical research aimed at improving the therapy and diagnosis of breast cancer using PDT based on the physicochemical differences in healthy and diseased tissues and the tissues undergoing treatment.

Autophagy Regulation and Photodynamic Therapy: Insights to Improve Outcomes of Cancer Treatment

Cancer is considered an age-related disease that, over the next 10 years, will become the most prevalent health problem worldwide. Although cancer therapy has remarkably improved in the last few decades, novel treatment concepts are needed to defeat this disease. Photodynamic Therapy (PDT) signalize a pathway to treat and manage several types of cancer. Over the past three decades, new light sources and photosensitizers (PS) have been developed to be applied in PDT. Nevertheless, there is a lack of knowledge to explain the main biochemical routes needed to trigger regulated cell death mechanisms, affecting, considerably, the scope of the PDT. Although autophagy modulation is being raised as an interesting strategy to be used in cancer therapy, the main aspects referring to the autophagy role over cell succumbing PDT-photoinduced damage remain elusive. Several reports emphasize cytoprotective autophagy, as an ultimate attempt of cells to cope with the photo-induced stress and to survive. Moreover, other underlying molecular mechanisms that evoke PDT-resistance of tumor cells were considered. We reviewed the paradigm about the PDT-regulated cell death mechanisms that involve autophagic impairment or boosted activation. To comprise the autophagy-targeted PDT-protocols to treat cancer, it was underlined those that alleviate or intensify PDT-resistance of tumor cells. Thereby, this review provides insights into the mechanisms by which PDT can be used to modulate autophagy and emphasizes how this field represents a promising therapeutic strategy for cancer treatment.

Downregulation of Rac1/PAK1/LIMK1/cofilin signaling pathway in colon cancer SW620 cells treated with Chlorin e6 photodynamic therapy

BACKGROUND

Colorectal cancer is one of the most common gastrointestinal malignancies. Photodynamic therapy (PDT) is a novel and non-invasive treatment for tumors as PDT features small trauma, good applicability, andaccurate targeting. PDT may also be a potential treatment for colon cancer as itmay may induce suppressive effects on metastatic potential.. However, the molecular mechanism of the Chlorin e6 Photodynamic therapy (Ce6-PDT) inhibiting the migration of human colon cancer SW620 cells remains unclear.

METHODS

Scratch wound healing assay, scanning electron microscope, MTT, immunofluorescence and laser confocal technique were used to investigate the suppressive effects of Ce6-PDT on the SW620 cells migration, pseudopodia, viability and the actin cytoskeleton. The effect of Ce6-PDT on actin-Filaments and signaling molecules of the Rac1/PAK1/LIMK1/cofilin signaling pathway in SW620 cells were examined by western blot analysis. RNA interference (RNAi) technology was used to establish siRNA-Rac1/SW620 cells. The combined effects of Ce6-PDT and RNAi on colon cancer SW620 cells was investigated by the same technology and methods mentioned above to clarify the signal transduction effect of Rac1/PAK1/LIMK1/cofilin signaling pathway in Ce6-PDT caused inhibition of SW620 cell migration.

RESULTS

The healing and migration rate of the SW620 cells was significantly reduced and the cell pseudopodia were reduced or disappeared by Ce6-PDT. The Immunofluorescence and western blot analysis results showed that Ce6-PDT destroy microfilament's original structure and significantly downregulated F-actin protein expression. The Rac1/PAK1/LIMK1/cofilin signaling pathway was downregulated by Ce6-PDT. Furthermore, the RNAi significantly strengthened the effect of Ce6-PDT on colon cancer SW620 cells migration.

CONCLUSIONS

Actin cytoskeleton and protrusions of SW620 cells correlate with its migration ability. Ce6-PDT suppresses SW620 cells migration by downregulating the Rac1/PAK1/LIMK1/cofilin signaling pathway, and its suppressive effect was enhanced by knocking down Rac1 gene expression.

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.

Honokiol Suppression of Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Gastric Cancer Cell Biological Activity and Its Mechanism

BACKGROUND The purpose of our study was to determine the effects and mechanisms of honokiol on human epidermal growth factor receptor 2 (HER2)-positive gastric cancer cells by in vitro study. MATERIAL AND METHODS We measured HER2 expression in different gastric cancer cell lines by real-time quantitative polymerase chain reaction (RT-qPCR) and western blot (WB) assay. Cell proliferation, apoptosis, and cell cycle were evaluated by cell-counting kit 8 and flow cytometry assays. The invading cell numbers and wound-healing rates were measured by transwell and wound-healing assays. Phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), P21, and matrix metalloproteinase (MMP)-9 proteins and messenger ribonucleic acid (mRNA) expression were measured by WB and RT-qPCR assay. HER2 protein expression was evaluated by cellular immunofluorescence. RESULTS Honokiol suppressed cell proliferation via increasing cell apoptosis, invasion, and migration with dose dependence. By WB and RT-qPCR assays, compared with the control group, PI3K, AKT, P21, and MMP-9 proteins and mRNA expression were significantly different (P<0.05). By cellular immunofluorescence, HER2 protein expression was significantly depressed in honokiol-treated groups compared with control groups (P<0.05). CONCLUSIONS Honokiol has suppressive effects on HER2-positive gastric cancer cell biological activities via regulation of HER2/PI3K/AKT pathways in vitro.

Counteracting Cisplatin-Induced Testicular Damages by Natural Polyphenol Constituent Honokiol

Cisplatin, despite its anti-cancer ability, exhibits severe testicular toxicities when applied systemically. Due to its wide application in cancer treatment, reduction of its damages to normal tissue is an imminent clinical need. Here we evaluated the effects of honokiol, a natural lipophilic polyphenol compound, on cisplatin-induced testicular injury. We showed in-vitro and in-vivo that nanosome-encapsulated honokiol attenuated cisplatin-induced DNA oxidative stress by suppressing intracellular reactive oxygen species production and elevating gene expressions of mitochondrial antioxidation enzymes. Nanosome honokiol also mitigated endoplasmic reticulum stress through down regulation of Bip-ATF4-CHOP signaling pathway. Additionally, this natural polyphenol compound diminished cisplatin-induced DNA breaks and cellular apoptosis. The reduced type I collagen accumulation in the testis likely attributed from inhibition of TGFβ1, αSMA and ER protein TXNDC5 protein expression. The combinatorial beneficial effects better preserve spermatogenic layers and facilitate repopulation of sperm cells. Our study renders opportunity for re-introducing cisplatin to systemic anti-cancer therapy with reduced testicular toxicity and restored fertility.

A Novel Synthetic Compound (E)-5-((4-oxo-4H-chromen-3-yl)methyleneamino)-1-phenyl-1H-pyrazole-4-carbonitrile Inhibits TNFα-Induced MMP9 Expression via EGR-1 Downregulation in MDA-MB-231 Human Breast Cancer Cells

Breast cancer is a common malignancy among women worldwide. Gelatinases such as matrix metallopeptidase 2 (MMP2) and MMP9 play crucial roles in cancer cell migration, invasion, and metastasis. To develop a novel platform compound, we synthesized a flavonoid derivative, (E)-5-((4-oxo-4H-chromen-3-yl)methyleneamino)-1-phenyl-1H-pyrazole-4-carbonitrile (named DK4023) and characterized its inhibitory effects on the motility and MMP2 and MMP9 expression of highly metastatic MDA-MB-231 breast cancer cells. We found that DK4023 inhibited tumor necrosis factor alpha (TNFα)-induced motility and F-actin formation of MDA-MB-231 cells. DK4023 also suppressed the TNFα-induced mRNA expression of MMP9 through the downregulation of the TNFα-extracellular signal-regulated kinase (ERK)/early growth response 1 (EGR-1) signaling axis. These results suggest that DK4023 could serve as a potential platform compound for the development of novel chemopreventive/chemotherapeutic agents against invasive breast cancer.

Antitumor effects and mechanisms of pyropheophorbide‑α methyl ester‑mediated photodynamic therapy on the human osteosarcoma cell line MG‑63

Photodynamic therapy (PDT) is a promising treatment for osteosarcoma, and pyropheophorbide-α methyl ester (MPPa) is a second-generation photosensitizer for tumor treatment. The present study aimed to determine the efficacy and possible mechanisms of MPPa-PDT in the treatment of osteosarcoma MG-63 cells. Flow cytometry and western blotting were used to detect cell cycle-related indicators Cyclin D1, Cyclin E, Cyclin A and Cyclin B1. Cell migration and invasion abilities were detected using wound-healing and Transwell chamber assays. Cellular endoplasmic reticulum stress (ERS), autophagy and apoptosis-related indicators were detected by flow cytometry and western blotting. The results demonstrated that MPPa-PDT blocked the MG-63 cell cycle and inhibited cell migration and invasion. Additionally, MPPa-PDT inhibited the activation of the Akt/mammalian target of rapamycin (mTOR) pathway. MG-63 cells underwent ERS-induced apoptosis following MPPa-PDT treatment. Pretreatment with the mTOR phosphorylation inhibitor rapamycin affected the autophagy of MPPa-PDT-induced osteosarcoma MG-63 cells and enhanced apoptosis through targeting mTOR.