Benzothiazolium-based NIR AIE photosensitizers with type I and II ROS generation for efficient mitochondria-targeted photodynamic therapy.

In this work, a near-infrared emissive photosensitizer of 3,3-dimethyl-N,N-diphenyl-2-(thiophen-2-yl)-3H-indol-6-amine functionlized benzothiazolium (DPITT) was developed. DPITT exhibited aggregation-induced emission effect and potent type I and II reactive oxygen species generation capacities after white light irradiation. Taking advantage of the cationic feature, DPITT penetrated the cell membrane and selectively accumulated in the mitochondria in living cells. Upon white light irradiation, the photosensitized DPITT was able to induce mitochondrial dysfunction, leading to cell death. Photosensitized DPITT was further applied to disrupt the multicellular tumour spheroids, demonstrating its potential application in inhibiting hypoxic solid tumours.

Analysis of the relationship between color and natural pigments of tobacco leaves during curing.

Color is one of the most important indicators for the flue-cured tobacco quality. The color change of tobacco has a great relationship with the natural pigments in the tobacco. The relationship between color characteristics and the content of natural pigments in tobacco leaves during curing was investigated. The middle part of variety K326 tobacco was taken at each key time point during the curing process to determine the changes of color characteristics, moisture, pigment and polyphenol content. The results showed that moisture content of wet basis of tobacco gradually decreased from 72 to 18% during the curing process, the b* value increased and then decreased, and the a* value increased significantly. The lutein and ß-carotene content decreased to 63.83 µg/g and 28.3 µg/g, respectively. The total polyphenols content increased to 50.19 mg/g. Meanwhile, the a* value was significantly and positively correlated with polyphenols content and negatively correlated with pigments content. Cluster analysis showed that the samples were divided into three categories: samples with the curing time of 0 h, 24-72 h, and 84-132 h. These results demonstrated that the color change of tobacco during curing process can be divided into three stages from the perspective of chemical composition, which are strongly related to the degradation of pigments and the transformation of polyphenols.

Coordination-Driven Self-Assembly of Biomedicine to Enhance Photodynamic Therapy by Inhibiting Proteasome and Bcl-2.

Tumor cells resist oxidative damage and apoptosis by activating defense mechanisms. Herein, a self-delivery biomedicine (designated as BSC) is developed by the self-assembly of Bortezomib (BTZ), Sabutoclax (Sab) and Chlorin e6 (Ce6). Interestingly, BTZ can be coordinated with Sab to promote the assembly of uniform ternary biomedicine through non-covalent intermolecular interactions. Moreover, BTZ as a proteasome inhibitor can prevent tumor cells from scavenging damaged proteins to reduce their oxidative resistance. Sab can downregulate B-cell lymphoma 2 (Bcl-2) to decrease the antiapoptotic protein. Both the proteasome and Bcl-2 inhibitions contribute to increasing cell apoptosis and amplifying photodynamic therapy (PDT) efficacy of Ce6. Encouragingly, carrier-free BSC receives all biological activities of these assembly elements, including photodynamic performance as well as inhibitory capabilities of proteasome and Bcl-2. Besides, BSC has a preferable cellular uptake ability and tumor retention property, which increase the drug delivery efficiency and bioavailability. In vitro and in vivo research demonstrate the superior PDT efficiency of BSC by proteasome and Bcl-2 inhibitions. Of special note, the coordination-driven self-assembly of BSC is pH-responsive, which can be disassembled for controlled drug release upon tumor acidic microenvironment. This study will expand the applicability of self-delivery nanomedicine with sophisticated mechanisms for tumor treatment.

Paraptosis Inducer to Effectively Trigger Immunogenic Cell Death for Metastatic Tumor Immunotherapy with IDO Inhibition.

Paraptosis is characterized by the extensive vacuolization of endoplasmic reticulum (ER) and mitochondria, which will cause the release of damage-associated molecular patterns to promote immunogenic cell death (ICD). However, the tumor can develop an immunosuppressive microenvironment to affect the ICD activation for the purpose of immune escape. Herein, a paraptosis inducer (CMN) is constructed to amplify the ICD effect for efficient immunotherapy by inhibiting the activity of indoleamine 2,3-dioxygenase (IDO). Initially, CMN is prepared by the assembly of copper ions (Cu2+), morusin (MR), and IDO inhibitor (NLG919) through noncovalent interactions. Without the need for extra drug carriers, CMN possesses very high drug contents and exhibits a favorable GSH responsiveness for disassembly. Subsequently, the released MR can trigger paraptosis to cause extensive vacuolization of ER and mitochondria, contributing to activating ICD for immunotherapy. Moreover, NLG919 would inhibit IDO to remodel the tumor microenvironment and promote the activation of cytotoxic T cells, leading to an intensive antitumor immunity. Abundant in vivo studies indicate that CMN is superior in suppressing the proliferations of not only primary tumor but also metastatic and rechallenged tumors. Such a GSH-responsive paraptosis inducer might provide a promising strategy to trigger ICD and enhance tumor immunotherapy.

Circ_0020256 induces fibroblast activation to drive cholangiocarcinoma development via recruitment of EIF4A3 protein to stabilize KLF4 mRNA.

Cancer-associated fibroblasts (CAFs) are a kind of stromal cells in the cholangiocarcinoma (CCA) microenvironment, playing crucial roles in cancer development. However, the potential mechanisms of the interaction between CCA cells and CAFs remain obscure. This work investigated the role of circ_0020256 in CAFs activation. We proved circ_0020256 was up-regulated in CCA. High circ_0020256 expression facilitated TGF-ß1 secretion from CCA cells, which activated CAFs via the phosphorylation of Smad2/3. Mechanistically, circ_0020256 recruited EIF4A3 protein to stabilize KLF4 mRNA and upregulate its expression, then KLF4 bound to TGF-ß1 promoter and induced its transcription in CCA cells. KLF4 overexpression abrogated the inhibition of circ_0020256 silencing in TGF-ß1/Smad2/3-induced CAFs activation. Furthermore, CCA cell growth, migration, and epithelial-mesenchymal transition were favored by CAFs-secreted IL-6 via autophagy inhibition. We also found circ_0020256 accelerated CCA tumor growth in vivo. In conclusion, circ_0020256 promoted fibroblast activation to facilitate CCA progression via EIF4A3/KLF4 pathway, providing a potential intervention for CCA progression.

Application of Laparoscopic Hepatectomy Combined with Intraoperative Microwave Ablation in Colorectal Cancer Liver Metastasis.

Laparoscopic hepatectomy is a common treatment for colorectal cancer liver metastasis. Previously, a sufficient number of functional liver masses had to be maintained during laparoscopic hepatectomy, with a residual liver volume of >40% in cirrhotic patients and >30% in non-cirrhotic patients. The high incidence of complications such as bleeding, bile leakage, or liver failure due to the exposure and difficulty of the resection of specific liver segments such as S2 and S7 reduces the success rate of liver resection. At present, microwave ablation is mainly applied in the treatment of liver metastasis using a percutaneous approach, which makes it difficult to identify hidden parts or small lesions. For some liver segments, the percutaneous puncture of liver segment 7 (S7) is likely to pass through the thoracic cavity, and the percutaneous puncture of liver segment 2 (S2) adjacent to the diaphragm is likely to injure the diaphragm and heart; these issues restrict the application of percutaneous ablation in colorectal cancer liver metastasis. Considering multiple lesions, laparoscopic microwave ablation combined with hepatectomy was performed in this study. The location of the lesions was determined by contrast-enhanced ultrasound under laparoscopy, and small lesions that were difficult to detect before the operation were identified. For the scattered lesions, which had diameters less than 3 cm and were difficult to resect, ablation was adopted to substitute hepatectomy. This technique helped to more explicitly locate the tumors, simplified the operation procedures, reduced the risk of complications such as bleeding and bile leakage, shortened the operation time, accelerated the postoperative recovery, significantly improved the success rate of operation, and enhanced the clinical prognosis of colorectal cancer liver metastasis by surgical resection.

Self-delivery biomedicine for enhanced photodynamic therapy by feedback promotion of tumor autophagy.

Reactive oxygen species (ROS) generated during photodynamic therapy (PDT) can induce autophagy to protect tumor cell from PDT-induced apoptosis. In this work, a self-delivery autophagy regulator (designated as CeCe) is developed for autophagy promotion sensitized PDT against tumor. Briefly, CeCe is prepared by the assembly of a photosensitizer of chlorin e6 (Ce6) and autophagy promoter of celastrol. By virtue of intermolecular interactions, Ce6 and celastrol are able to self-assemble into nanomedicine with great photodynamic performance and autophagy regulation capacity. Under light irradiation, CeCe would produce ROS in tumor cells to amplify the oxidative stress and promote cell autophagy. As a result, CeCe exhibits an enhanced photo toxicity by inducing autophagic cell death. In vivo experiments indicate that CeCe can predominantly accumulate in tumor tissue for a robust PDT. Moreover, CeCe has a superior therapeutic efficiency compared to monotherapy and combined treatment of Ce6 and celastrol, suggesting a synergistic antitumor effect of PDT and autophagy promotion. This self-delivery nanomedicine may advance the development of the co-delivery nanoplatform to improve the antitumor efficacy of PDT by promoting autophagy. STATEMENT OF SIGNIFICANCE: Autophagy is a "double-edged sword" in cellular homeostasis and metabolism, which can promote tumor progression but also induce an unknown impact on tumor inhibition. In this work, a self-delivery autophagy regulator (designated as CeCe) was developed for autophagy promotion sensitized photodynamic therapy (PDT). By virtue of intermolecular interactions, Ce6 and celastrol were found to self-assemble into stable CeCe without drug excipients, which exhibited great photodynamic performance and autophagy regulation capacity. In vitro and in vivo findings demonstrated a superior tumor suppression ability of CeCe over the monotherapy as well as the combined treatment of Ce6 and celastrol, suggesting a synergistic antitumor efficacy by PDT and autophagy promotion.

Epigenetic reprogramming of carrier free photodynamic modulator to activate tumor immunotherapy by EZH2 inhibition.

Tumor cells are characterized by unlimited proliferation and escape of immune clearance, which are closely associated with the down regulation of surface antigens. In this work, a carrier free photodynamic modulator (CeTaz) is developed to improve immunosuppressive tumor microenvironment and promote the recognition of tumors by T cells by epigenetic reprogramming. Specifically, CeTaz is assembled by chlorine e6 (Ce6) and tazemetostat (Taz) through intermolecular interactions. Upon light irradiation, CeTaz is able to promote the generation of reactive oxygen species (ROS) for a robust photodynamic therapy (PDT) to inhibit localized tumor growth. Meanwhile, the PDT also induces immunogenic cell death (ICD) to initiate immune response, leading to the activation of effector T cells. More importantly, CeTaz could inhibit the epigenetic regulator of EZH2 to suppress the methylation of H3K27, which would promote tumor cells to express MHC-I and release CXCL10. Consequently, the epigenetically reprogrammed tumor cells are readily recognized by effector T cells to enhance the antitumor immunity. Results indicate that the PDT activated immunotherapy of CeTaz could simultaneously inhibit the growth of primary and distant tumors with a low system toxicity. This study would advance the development of carrier free nanomedicine for precise treatment of metastatic tumor.

SHH/GLI2-TGF-ß1 feedback loop between cancer cells and tumor-associated macrophages maintains epithelial-mesenchymal transition and endoplasmic reticulum homeostasis in cholangiocarcinoma.

BACKGROUND: Tumor-associated macrophages (TAMs) play a dual role in tumors. However, the factors which drive the function of TAMs in cholangiocarcinoma remain largely undefined. METHODS: SHH signaling pathway and endoplasmic reticulum stress (ERS) indicators were detected in clinical tissues and cholangiocarcinoma cell lines. TAMs were co-cultured with cholangiocarcinoma cells under conditions of hypoxia/normoxia. Polarized TAMs were counted by flow cytometry, and TGF-ß1 levels in cell supernatants were detected by ELISA. The effects of glioma-associated oncogene GLI2 on TAMs themselves and cholangiocarcinoma cells were examined by conducting interference and overexpression assays. RESULTS: The SHH signaling pathway and ERS were both activated in tumor tissues or tumor cell lines under conditions of hypoxia. In co-culture experiments, the presence of cholangiocarcinoma cells increased the proportion of M2-polarized TAMs and the secretion of TGF-ß1 by TAMs, while knockdown of SHH expression reversed those increases. Overexpression of GLI2 in TAMS or stimulation of TAMS with Hh-Ag1.5 increased their levels of TGF-ß1 expression. Furthermore, under co-culture conditions, interference with GLI2 expression in TAMs reduced the tumor cell migration, invasion, and ER homeostasis induced by Hh-Ag1.5-pretreated TAMs. Under conditions of hypoxia, the presence of cholangiocarcinoma cells promoted the expression of GLI2 and TGF-ß1 in Tams, and in turn, TAMs inhibited the apoptosis and promoted the migration and invasion of cholangiocarcinoma cells. In vivo, an injection of cholangiocarcinoma cells plus TAMs contributed to the growth, EMT, and ER homeostasis of tumor tissue, while an injection of TAMs with GLI2 knockdown had the opposite effects. CONCLUSION: Cholangiocarcinoma cells regulated TAM polarization and TGF-ß1 secretion via a paracrine SHH signaling pathway, and in turn, TAMs promoted the growth, EMT, and ER homeostasis of cholangiocarcinoma cells via TGF-ß1.

Cascade Immune Activation of Self-Delivery Biomedicine for Photodynamic Immunotherapy Against Metastatic Tumor.

Photodynamic therapy (PDT) can generate reactive oxygen species (ROS) to cause cell apoptosis and induce immunogenic cell death (ICD) to activate immune response, becoming a promising antitumor modality. However, the overexpressions of indoleamine 2,3-dioxygenase (IDO) and programmed cell death ligand 1 (PD-L1) on tumor cells would reduce cytotoxic T cells infiltration and inhibit the immune activation. In this paper, a simple but effective nanosystem is developed to solve these issues for enhanced photodynamic immunotherapy. Specifically, it has been constructed a self-delivery biomedicine (CeNB) based on photosensitizer chlorine e6 (Ce6), IDO inhibitor (NLG919), and PD1/PDL1 blocker (BMS-1) without the need for extra excipients. Of note, CeNB possesses fairly high drug content (nearly 100%), favorable stability, and uniform morphology. More importantly, CeNB-mediated IDO inhibition and PD1/PDL1 blockade greatly improve the immunosuppressive tumor microenvironments to promote immune activation. The PDT of CeNB not only inhibits tumor proliferation but also induces ICD response to activate immunological cascade. Ultimately, self-delivery CeNB tremendously suppresses the tumor growth and metastasis while leads to a minimized side effect. Such simple and effective antitumor strategy overcomes the therapeutic resistance against PDT-initiated immunotherapy, suggesting a potential for metastatic tumor treatment in clinic.

Long-term efficacy of percutaneous transhepatic cholangioscopy-guided photodynamic therapy for postoperative recurrent extrahepatic cholangiocarcinoma.

BACKGROUND: Cholangiocarcinoma recurs frequently following excision surgery and is usually inoperable, while radiotherapy, chemotherapy, and immunotherapy are of limited benefit. As palliative care, percutaneous transhepatic cholangial drainage (PTCD) can relieve biliary obstruction, prevent jaundice, and maintain quality of life (QOL), but does not improve overall survival. In contrast, photodynamic therapy (PDT) has been demonstrated to prolong the survival of inoperable cancer patients. OBJECTIVE: This study evaluated the clinical efficacy of percutaneous transhepatic cholangioscopy (PTCS)-guided PDT following PTCD versus PTCD alone for recurrent inoperable cholangiocarcinoma. METHODS: The case files of 39 patients with postoperative recurrence were retrospectively analyzed, including 18 receiving PTCS-guided PDT (PTCS-PDT group) and 21 receiving PTCD only as a control (PTCD group). Survival time was compared by Kaplan-Meier analysis and log-rank test, and QOL by the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-HEP) questionnaire. Clinicodemographic factors, including serum bilirubin and adverse reaction rates, were compared by Student's t-test or Fisher's exact test. The maximum follow-up period was 71 months. RESULTS: Median survival time was significantly longer in the PTCS-PDT group than the PTCD group (23 months vs. 10 months, P = 0.00001). At 6 and 12 months post-treatment, total FACT-HEP score was lower in the PTCS-PDT group (P < 0.05), indicating improved QOL. There was no significant difference in total adverse events incidence between groups (19 [51.4%] vs. 15 [71.4%]; P = 0.131). CONCLUSION: PTCS-guided PDT can prolong survival and improve the QOL of patients with postoperative cholangiocarcinoma recurrence without increasing complications. SIGNIFICANT AND/OR NEW FINDINGS: Compared to PTCD alone, PTCS-guided PDT significantly prolonged the survival time of patients with postoperative recurrent extrahepatic cholangiocarcinoma. Photodynamic therapy also improved patient quality of life by facilitating timely removal of the PTCD drainage tube. PTCS-guided PDT did not increase surgery-related complications except for skin phototoxicity, which can be easy avoided and treated.

Tumor-associated macrophages promote cholangiocarcinoma progression via exosomal Circ_0020256.

This study investigated the exosomal circular RNAs (CircRNAs) produced by tumor-associated macrophages and delivered into the microenvironment of cholangiocarcinoma cells in order to use them as molecular targets for clinical therapy. Tumor-associated M2 macrophages (TAMs) were induced from THP-1 cells and identified by flow cytometry. The TAM-secreted exosomes were isolated from conditioned medium and a CircRNA microarray assay was performed to identify CircRNAs that were uniquely expressed in the isolated exosomes. Circ_0020256 was especially identified based on having the highest differential expression level among all of the CircRNA candidates. In vitro and in vivo experiments were performed to assess the effects of TAMs, exosomes, and Circ_0020256 on the growth and migration of cholangiocarcinoma (CCA) cells. The induced TAMs promoted the proliferation, migration, and invasion of CCA cells and those effects were mediated by exosomes secreted by the TAMs. In CCA cells (RBE and HCCC-9810), Circ_0020256 significantly promoted cellular activity by interacting with its intra-cellular microRNA target, miR-432-5p. In contrast, overexpression of transcription factor E2F3 in CCA cells restored the CCA cellular activities that were inhibited by miR-432-5p. On the other hand, treatment with small interference RNA (siRNA) for Circ_0020256 inhibited CCA cell proliferation, migration, and invasion both in vitro and in vivo. In conclusion, Circ_0020256 in TAM-secreted exosomes promoted the proliferation, migration, and invasion of CCA cells, and that promotional activity was regulated via a Circ_0020256/miR-432-5p/E2F3 axis.