Macrophages mediated delivery of chlorin e6 and treatment of lung cancer by photodynamic reprogramming

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.

Targeting tumor-associated macrophage: an adjuvant strategy for lung cancer therapy

The emergence of immunotherapy has revolutionized the treatment landscape for various types of cancer. Nevertheless, lung cancer remains one of the leading causes of cancer-related mortality worldwide due to the development of resistance in most patients. As one of the most abundant groups of immune cells in the tumor microenvironment (TME), tumor-associated macrophages (TAMs) play crucial and complex roles in the development of lung cancer, including the regulation of immunosuppressive TME remodeling, metabolic reprogramming, neoangiogenesis, metastasis, and promotion of tumoral neurogenesis. Hence, relevant strategies for lung cancer therapy, such as inhibition of macrophage recruitment, TAM reprograming, depletion of TAMs, and engineering of TAMs for drug delivery, have been developed. Based on the satisfactory treatment effect of TAM-targeted therapy, recent studies also investigated its synergistic effect with current therapies for lung cancer, including immunotherapy, radiotherapy, chemotherapy, anti-epidermal growth factor receptor (anti-EGFR) treatment, or photodynamic therapy. Thus, in this article, we summarized the key mechanisms of TAMs contributing to lung cancer progression and elaborated on the novel therapeutic strategies against TAMs. We also discussed the therapeutic potential of TAM targeting as adjuvant therapy in the current treatment of lung cancer, particularly highlighting the TAM-centered strategies for improving the efficacy of anti-programmed cell death-1/programmed cell death-ligand 1 (anti-PD-1/PD-L1) treatment.

A Dihydroartemisinin-Loaded Nanoreactor Motivates Anti-Cancer Immunotherapy by Synergy-Induced Ferroptosis to Activate Cgas/STING for Reprogramming of Macrophage

Infiltration of tumor-associated macrophages (TAM) characterized by an M2 phenotype is an overriding feature in malignant tumors. Reprogramming TAM is the most cutting-edge strategy for cancer therapy. In the present study, an iron-based metal-organic framework (MOF) nanoreactor loaded with dihydroartemisinin (DHA) is developed, which provides high uptake by TAM and retains their viability, thus effectively addressing the inefficiency of the DHA at low concentrations. Impressively, DHA@MIL-101 can selectively accumulate in tumor tissues and remodel TAM to the M1 phenotype. The results of RNA sequencing further suggest that this nanoreactor may regulate ferroptosis, a DNA damage signaling pathway in TAM. Indeed, the outcomes confirm that DHA@MIL-101 triggers ferroptosis in TAM. In addition, the findings reveal that DNA damage induced by DHA nanoreactors activates the intracellular cGAS sensor, resulting in the binding of STING to IRF3 and thereby up-regulating the immunogenicity. In contrast, blocking ferroptosis impairs DHA@MIL-101-induced activation of STING signaling and phenotypic remodeling. Finally, it is shown that DHA nanoreactors deploy anti-tumor immunotherapy through ferroptosis-mediated TAM reprogramming. Taken together, immune efficacy is achieved through TAM's remodeling by delivering DHA and iron ions into TAM using nanoreactors, providing a novel approach for combining phytopharmaceuticals with nanocarriers to regulate the immune microenvironment.

Cross-talk between necroptosis-related lncRNAs to construct a novel signature and predict the immune landscape of lung adenocarcinoma patients

Background: As a new style of cell death, necroptosis plays a crucial role in tumor immune microenvironment. LncRNAs have been identified to act as competitive RNAs to influence genes involved in necroptosis. Therefore, we aim to create a signature based on necroptosis-related lncRNAs to predict the prognosis and immune landscape of lung adenocarcinoma (LUAD) patients in this study.

Methods: TCGA database was used to acquire RNA sequencing (RNA-Seq) data and clinical information for 59 lung normal samples and 535 lung adenocarcinoma samples. The Pearson correlation analysis, univariate cox regression analysis and least absolute shrinkage and selection operator (LASSO) cox regression were performed to construct the prognostic NRlncRNAs signature. Then we used Kaplan-Meier (K-M) analysis, time-dependent ROC curves, univariate and multivariate cox regression analysis, and nomogram to validate this signature. In addition, GO, KEGG, and GSVA were analyzed to investigate the potential molecular mechanism. Moreover, we analyzed the relationship between our identified signature and immune microenvironment, TMB, and some clinical characteristics. Finally, we detected the expression of the six necroptosis-related lncRNAs in cells and tissues.

Results: We constructed a NRlncRNAs signature consisting of six lncRNAs (FRMD6-AS1, LINC01480, FAM83A-AS1, FRMD6-AS1, MED4-AS1, and LINC01415) in LUAD. LUAD patients with high risk scores had lower chance of survival with an AUC of 0.739, 0.709, and 0.733 for 1-year, 3-year, and 5-year respectively. The results based on GO, KEGG, and GSVA enrichment analysis demonstrated that NRlncRNAs signature-related genes were mainly correlated with immune pathways, metabolic-and cell growth-related pathways, cell cycle, and apoptosis. Moreover, the risk score was correlated with the immune status of LUAD patients. Patients with higher risk scores had lower ESTIMATE scores and higher TIDE scores. The risk score was positively correlated with TMB. LINC01415, FRMD6-AS1 and FAM83A-AS1 were significantly overexpressed in lung adenocarcinoma, while the expression levels of MED4-AS1 and LINC01480 were lower in lung adenocarcinoma.

Conclusion: Overall, an innovative prognostic signature based on NRlncRNAs was developed for LUAD through comprehensive bioinformatics analysis, which can act as a predictor of immunotherapy and may provide guidance for clinicians.

Dihydroartemisinin remodels macrophage into an M1 phenotype via ferroptosis-mediated DNA damage

Lung cancer recruits tumor-associated macrophages (TAMs) massively, whose predominantly pro-tumor M2 phenotype leads to immunosuppression. Dihydroartemisinin (DHA) has been proven to remodel TAM into an anti-tumor M1 phenotype at certain concentrations in the present study, which was hypothesized to facilitate anti-lung cancer immunotherapy. However, how DHA remodels the TAM phenotype has not yet been uncovered. Our previous work revealed that DHA could trigger ferroptosis in lung cancer cells, which may also be observed in TAM thereupon. Sequentially, in the current study, DHA was found to remodel TAM into the M1 phenotype in vitro and in vivo. Simultaneously, DHA was observed to trigger ferroptosis in TAM and cause the DNA damage response and NF-κB activation. Conversely, the DHA-induced DNA damage response and NF-κB activation in TAM were attenuated after the inhibition of ferroptosis in TAM using an inhibitor of ferroptosis. Importantly, a ferroptosis inhibitor could also abolish the DHA-induced phenotypic remodeling of TAM toward the M1 phenotype. In a nutshell, this work demonstrates that DHA-triggered ferroptosis of TAM results in DNA damage, which could activate downstream NF-κB to remodel TAM into an M1 phenotype, providing a novel strategy for anti-lung cancer immunotherapy. This study offers a novel strategy and theoretical basis for the use of traditional Chinese medicine monomers to regulate the anti-tumor immune response, as well as a new therapeutic target for TAM phenotype remodeling.

A novel DNA methylation-driver gene signature for long-term survival prediction of hepatitis-positive hepatocellular carcinoma patients

BACKGROUND

Abnormal DNA methylation is one of the most general epigenetic modifications in hepatocellular carcinoma (HCC). Recent research showed that DNA methylation was a prognostic indicator of all-cause HCC and nonviral HCC. However, whether DNA methylation-driver genes could be used for predicting survival, the probability of hepatitis-positive HCC remains unclear.

METHODS

In this study, DNA methylation-driver genes (MDGs) were screened by a joint analysis of methylome and transcriptome data of 142 hepatitis-positive HCC patients. Subsequently, a prognostic risk score and nomogram were constructed. Finally, correlation analyses between the risk score and signaling pathways and immunity were conducted by GSVA and CIBERSORT.

RESULTS

Through random forest screening and Cox progression analysis, 10 prognostic methylation-driver genes (AC008271.1, C11orf53, CASP8, F2RL2, GBP5, LUCAT1, RP11-114B7.6, RP11-149I23.3, RP11-383 J24.1, and SLC35G2) were screened out. As a result, a prognostic risk score signature was constructed. The independent value of the risk score for prognosis prediction were addressed in the TCGA-HCC and the China-HCC cohorts. Next, clinicopathological features were analyzed and HBV status and histological grade were screened to construct a nomogram together with the risk score. The prognostic efficiency of the nomogram was validated by the calibration curves and the concordance index (C index: 0.829, 95% confidence interval: 0.794-0.864), while its clinical application ability was confirmed by decision curve analysis (DCA). At last, the relationship between the risk score and signaling pathways, as well as the correlations between immune cells were elucidated preliminary.

CONCLUSIONS

Taken together, our study explored a novel DNA methylation-driver gene risk score signature and an efficient nomogram for long-term survival prediction of hepatitis-positive HCC patients.

Chlorin e6-Induced Photodynamic Effect Polarizes the Macrophage Into an M1 Phenotype Through Oxidative DNA Damage and Activation of STING

The tumor-associated macrophage (TAM) serves as an immunosuppressive agent in the malignant tumor microenvironment, facilitating the development and metastasis of lung cancer. The photodynamic effect destabilizes cellular homeostasis owing to the generation of reactive oxygen species (ROS), resulting in the enhanced pro-inflammatory function of immunocytes. In our previous study, the Ce6-mediated photodynamic effect was found to have kept the viability of macrophages and to remodel them into the M1 phenotype. However, the mechanism remains unrevealed. The present study now explores the mechanism of photodynamic therapy (PDT)-mediated reprogramming of macrophages. As expected, Ce6-mediated PDT was capable of generating reactive oxygen species, which was continuously degraded, causing "low intensity" damage to DNA and thereby triggering subsequent DNA damage response in macrophages. The autophagy was thus observed in Ce6-treated macrophages and was shown to protect cells from being photodynamically apoptotic. More importantly, Ce6 PDT could activate the stimulator of interferon genes (STING) molecule, a sensor of DNA damage, which could activate the downstream nuclear factor kappa-B (NF-κB) upon activation, mediating the polarization of macrophages towards the M1 phenotype thereupon. In addition, inhibition of ROS induced by PDT attenuated the DNA damage, STING activation, and M1-phenotype reprogramming. Furthermore, the silence of the STING weakened Ce6 treatment-mediated M1 remodeling of macrophages as well. Altogether, these findings indicate the Ce6-induced photodynamic effect polarizes macrophages into an M1 phenotype through oxidative DNA damage and subsequent activation of the STING. This work reveals the crucial mechanism by which photodynamic therapy regulates the macrophage phenotype and also provides a novel intervenable signaling target for remodeling macrophages into the M1 phenotype.

Nanomedicine Strategies for Management of Drug Resistance in Lung Cancer

Lung cancer (LC) is one of the leading causes of cancer occurrence and mortality worldwide. Treatment of patients with advanced and metastatic LC presents a significant challenge, as malignant cells use different mechanisms to resist chemotherapy. Drug resistance (DR) is a complex process that occurs due to a variety of genetic and acquired factors. Identifying the mechanisms underlying DR in LC patients and possible therapeutic alternatives for more efficient therapy is a central goal of LC research. Advances in nanotechnology resulted in the development of targeted and multifunctional nanoscale drug constructs. The possible modulation of the components of nanomedicine, their surface functionalization, and the encapsulation of various active therapeutics provide promising tools to bypass crucial biological barriers. These attributes enhance the delivery of multiple therapeutic agents directly to the tumor microenvironment (TME), resulting in reversal of LC resistance to anticancer treatment. This review provides a broad framework for understanding the different molecular mechanisms of DR in lung cancer, presents novel nanomedicine therapeutics aimed at improving the efficacy of treatment of various forms of resistant LC; outlines current challenges in using nanotechnology for reversing DR; and discusses the future directions for the clinical application of nanomedicine in the management of LC resistance.

Ferroptosis triggered by dihydroartemisinin facilitates chlorin e6 induced photodynamic therapy by inhibiting GPX4 and enhancing ROS

Photodynamic therapy (PDT) is noninvasive, low toxicity, and photo-selective, but may be resisted by malignant cells. A previous study found chlorin e6 (Ce6) mediated PDT showed drug resistance in lung cancer cells (LLC), which may be associated with PDT-induced DNA damage response (DDR). DDR may up-regulate glutathione peroxidase 4 (GPX4), which in turn degrade ROS induced by PDT. However, dihydroartemisinin (DHA) was found to down-regulate GPX4. Accordingly, the DHA was hypothesized to improve the resistance to PDT. The present work explores the mechanism of Ce6 mediated drug resistance and reveals whether DHA can enhance the efficacy of PDT by suppressing GPX4. The in vitro experiments found Ce6 treatment did not inhibit the viability of LLC within 6 hr without inducing significant apoptosis, suggesting LLC were resistant to PDT. Further investigation demonstrated PDT could damage DNA and up-regulate GPX4, thus degrading the generated ROS. DHA effectively inhibited the viability of LLC and induced apoptosis. Importantly, DHA displayed a prominent inhibitory effect on the GPX4 expression and thereby triggered ferroptosis. Combining DHA with Ce6 for treatment of LLC resulted in the suppressed GPX4 and elevated ROS. Finally, the findings showed DHA combined with Ce6 exhibited superb anti-lung cancer efficacy. In summary, Ce6 PDT damages DNA, up-regulates GPX4 to degrade ROS, thereby inducing drug resistance. Down-regulation of GPX4 by DHA-triggered ferroptosis significantly enhances the efficacy of PDT. This study provides an outstanding theoretical basis for the regulation of the intratumoral redox system and improving PDT efficacy against lung cancer by herbal monomer DHA.

A Pilot Study of Fluorescence-Guided Resection of Pituitary Adenomas with Chlorin e6 Photosensitizer

Fluorescence diagnostics is one of the promising methods for intraoperative detection of brain tumor boundaries and helps in maximizing the extent of resection. This paper presents the results of a pilot study on the first use of the chlorin e6 photosensitizer and a two-channel video system for fluorescence-guided resection of pituitary adenomas. The study’s clinical part involved two patients diagnosed with hormonally inactive pituitary macroadenomas and one patient with a hormonally active one. All neoplasms had different sizes and growth patterns. The data showed accumulation of chlorin e6 in tumor tissues in high concentrations: Patient 1: 2 mg/kg, Patient 2: 5 mg/kg, and Patient 3: 4 mg/kg. For Patient 1, the residual part of the tumor was not resected since it was intimately attached to the anterior genu of the internal carotid artery. For Patients 2 and 3, no regions of increased Ce6 accumulation were detected in the tumor foci after resection. Therefore, the use of the Ce6 and a two-channel video system helped to achieve a high degree of tumor resection in each case.