Dihydroartemisinin-driven TOM70 inhibition leads to mitochondrial destabilization to induce pyroptosis against lung cancer.

Enhancement of malignant cell immunogenicity to relieve immunosuppression of lung cancer microenvironment is essential in lung cancer treatment. In previous study, we have demonstrated that dihydroartemisinin (DHA), a kind of phytopharmaceutical, is effective in inhibiting lung cancer cells and boosting their immunogenicity, while the initial target of DHA's intracellular action is poorly understood. The present in-depth analysis aims to reveal the influence of DHA on the highly expressed TOM70 in the mitochondrial membrane of lung cancer. The affinity of DHA and TOM70 was analyzed by microscale thermophoresis (MST), pronase stability, and thermal stability. The functions and underlying mechanism were investigated using western blots, qRT-PCR, flow cytometry, and rescue experiments. TOM70 inhibition resulted in mtDNA damage and translocation to the cytoplasm from mitochondria due to the disruption of mitochondrial homeostasis. Further ex and in vivo findings also showed that the cGAS/STING/NLRP3 signaling pathway was activated by mtDNA and thereby malignant cells underwent pyroptosis, leading to enhanced immunogenicity of lung cancer cells in the presence of DHA. Nevertheless, DHA-induced mtDNA translocation and cGAS/STING/NLRP3 mobilization were synchronously attenuated when TOM70 was replenished. Finally, DHA was demonstrated to possess potent anti-lung cancer efficacy in vitro and in vivo. Taken together, these data confirm that TOM70 is an important target for DHA to disturb mitochondria homeostasis, which further activates STING and arouses pyroptosis to strengthen immunogenicity against lung cancer thereupon. The present study provides vital clues for phytomedicine-mediated anti-tumor therapy.

Laser-triggered intelligent drug delivery and anti-cancer photodynamic therapy using platelets as the vehicle.

In our previous study, target drug delivery and treatment of malignant tumors have been achieved by using platelets as carriers loading nano-chemotherapeutic agents (ND-DOX). However, drug release from ND-DOX-loaded platelets is dependent on negative platelet activation by tumor cells, whose activation is not significant enough for the resulting drug release to take an effective anti-tumor effect. Exploring strategies to proactively manipulate the controlled release of drug-laden platelets is imperative. The present study innovatively revealed that photodynamic action can activate platelets in a spatiotemporally controlled manner. Consequently, based on the previous study, platelets were used to load iron oxide-polyglycerol-doxorubicin-chlorin e6 composites (IO-PG-DOX-Ce6), wherein the laser-triggered drug release ability and anti-tumor capability were demonstrated. The findings suggested that IO-PG-DOX-Ce6 could be stably loaded by platelets in high volume without any decrease in viability. Importantly and interestingly, drug-loaded platelets were significantly activated by laser irradiation, characterized by intracellular ROS accumulation and up-regulation of CD62p. Additionally, scanning electron microscopy (SEM) and hydrated particle size results also showed a significant aggregation response of laser irradiated-drug-loaded platelets. Further transmission electron microscopy (TEM) measurements indicated that the activated platelets released extracellularly their cargo drug after laser exposure, which could be taken up by co-cultured tumor cells. Finally, the co-culture model of drug-loaded platelets and tumor cells proved that laser-triggered delivery system of platelets could effectively damage the DNA and promote apoptosis of tumor cells. Overall, the present study discovers a drug-loaded platelets delivery using photodynamic effect, enabling laser-controlled intelligent drug delivery and anti-tumor therapy, which provides a novel and feasible approach for clinical application of cytopharmaceuticals.

What is the context?1. Platelets were applied to load IO-PG-DOX-Ce6, wherein the laser-triggered drug release and anti-tumor effect were investigated in vitro.2. The findings indicated that IO-PG-DOX-Ce6 could be stably loaded by platelets in high volume without any decrease in viability, which may attribute to the activation of autophagy in platelets.3. IO-PG-DOX-Ce6-loaded platelets could be significantly activated by laser irradiation (690 nm).4. Activated platelets released extracellularly their cargo drug after laser exposure, which could be taken up by co-cultured tumor cells5. The co-culture model of drug-loaded platelets and tumor cells proved that the laser-triggered delivery system of platelets could effectively damage the DNA and promote apoptosis of tumor cells.What is new?1. Platelets could be utilized as the vehicle to load photosensitizer-loaded-nano-drug.2. Photodynamic action can activate platelets in a spatiotemporally controlled manner, which could be a tool to regulate the activation of platelets.3. The laser-triggered activation of drug-loaded platelets allows for target release of cargo.4. The limitation of the current research is that only in vitro experiments were carried out to demonstrate our conclusions.What is impact?The present work provides a novel and feasible approach for the clinical application of cytopharmaceuticals.

Cepharanthine-mediated endoplasmic reticulum stress inhibits Notch1 via binding GRP78 for suppressing hepatocellular carcinoma metastasis.

BACKGROUND: The metastasis of hepatocellular carcinoma (HCC) leads to a poor prognosis, wherein the activation of Notch1 is an essential contributor. Cepharanthine (Cep) has been identified for its effective antiviral function and versatile intracellular targets. Our previous study has only reported the anti-cancer efficacy of Cep in lung cancer, without an in-depth exploration. Herein, the present study aims to investigate the anti-metastasis effect in HCC, the target involved, and the molecular mechanism of Cep. METHODS: Stable over-expression of Notch1-N1ICD yielded C5WN1 cells compared with C5WBF344 cells. The C5WN1 cells and C5WN1 cell-bearing mice were applied as the HCC model. The bioinformatics analysis, RNA sequencing, molecular docking, cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS), microscale thermophoresis (MST), and transient knockdown techniques were carried out to identify the underlying target. The apoptosis assay, immunofluorescent staining, qRT-PCR, Western blots, Elisa, flow cytometry, migration and scratching experiments, Transmission electron microscopy (TEM), laser scanning confocal microscopy (LSCM), micro-computed tomography (micro-CT), and histopathological experiments were conducted to assay the anti-HCC efficacy, functions, and mechanism. RESULTS: Notch1 had an increased expression in HCC and contributed to metastasis thereupon. Surprisingly, Cep (2 µg/ml in vitro, 5 mg kg-1in vivo) presented potent Notch1 signaling pathway inhibitory effect and anti-metastasis efficacy in C5WN1 cells and in situ mice models as evidenced by reduced Notch1/MMP-2/MMP-9 expression, TGF-ß release, decreased cell migration, diminished pulmonary metastases, and prolonged survival. RNA sequencing showed that the differential gene of Cep-treated HCC cells was positioned in the endoplasmic reticulum (ER). Molecular docking, CETSA, DARTS, and MST further identified that the possible target of Cep was GRP78, which was distributed in the ER. As expected, Cep (2 µg/ml) up-regulated the critical molecules of ER stress such as GRP78, induced ß-amyloid accumulation, and promoted calcium burst in HCC. In contrast, suppression of GRP78 attenuated Cep-induced ER stress. Furthermore, inhibition of ER stress abated Cep-induced Notch1 inactivation and HCC cells' migration. CONCLUSIONS: Taken together, the present study finds that Cep possesses excellent anti-metastasis of HCC, wherein the GRP78 could be directly bound and activated by Cep, leading to ER stress and Notch1 blockage. This study reveals for the first time the effect, critical target, and mechanism of the Cep-mediated anti-cancer effect, providing novel insights into the molecular target therapy by phytomedicine.

Indocyanine green-loaded platelet activated by photodynamic and photothermal effects for selective control of wound repair.

OBJECTIVE: Prompt and effective wound repair is an essential strategy to promote recovery and prevent infection in patients with various types of trauma. Platelets can release a variety of growth factors upon activation to facilitate revascularization and tissue repair, provided that their activation is uncontrollable. The present study is designed to explore the selective activation of platelets by photodynamic and photothermal effects (PDE/PTE) as well as the trauma repair mediated by PDE/PTE. MATERIALS AND METHODS: In the current research, platelets were extracted from the blood of mice. Indocyanine green (ICG) was applied to induce PDE/PTE. The uptake of ICG by platelets was detected by laser confocal microscopy and flow cytometry. The cellular integrity was measured by microscopy. The reactive oxygen species (ROS) generation and temperature of platelets were assayed by 2,7-Dichlorodihydrofluorescein diacetate (DCFH-DA) and temperature detector. The activation of platelets was measured by western blots (WB), dynamic light scattering (DLS), and scanning electron microscopy (SEM). The release of growth factor was detected by enzyme-linked immuno sorbent assay (Elisa), wherein the in vitro cell proliferation was investigated by 5-Ethynyl-2'-deoxyuridine (EDU) assay. The wound infection rates model and histological examination were constructed to assay the ICG-loaded platelet-mediated wound repair. RESULTS: Platelets could load with ICG, a kind of photodynamic and photothermal agent, as carriers and remain intact. Near-infrared (NIR) laser irradiation of ICG-loaded platelets (ICG@PLT) facilitated higher temperature and ROS generation, which immediately activated ICG@PLT, as characterized by increased membrane p-selectin (CD62p), cyclooxygenase-2 (COX-2), thromboxane A2 receptor (TXA2R) expression, elevated hydrated particle size, and prominent aggregation in platelets. Further investigation revealed that massive insulin-like growth factor (IGF) and platelet-derived growth factor (PDGF) were released from the activated ICG@PLT, which also promoted the proliferation of endothelial cells and keratinocytes in co-culture. In consequence, activated platelets and increased neovascularization could be observed in rats with wound infection treated by ICG@PLT in the presence of NIR. More impressively, the hydrogel containing ICG@PLT accelerated wound healing and suppressed inflammation under NIR, exhibiting excellent wound repair properties. CONCLUSION: Taken together, the current work identified that platelets could be activated by PDE/PTE and thereby release growth factor, potentiating wound repair in a controlled manner.