Jointly Depleting Glutathione Based on Self-Assembled Nanomicelles for Enhancing Photodynamic Therapy.

Photodynamic therapy (PDT) is one common ROS-generating therapeutic method with high tumor selectivity and low side effects. But the GSH-upregulation often alleviates its therapeutic efficiency. Here, we proposed a new strategy of jointly depleting GSH to enhance the therapeutic effect of PDT by preparing a nanomicelle by self-assembly method from GSH-activated photosensitizer DMT, curcumin, and amphiphilic polymer TPGS.

An unexpected strategy to alleviate hypoxia limitation of photodynamic therapy by biotinylation of photosensitizers.

The most common working mechanism of photodynamic therapy is based on high-toxicity singlet oxygen, which is called Type II photodynamic therapy. But it is highly dependent on oxygen consumption. Recently, Type I photodynamic therapy has been found to have better hypoxia tolerance to ease this restriction. However, few strategies are available on the design of Type I photosensitizers. We herein report an unexpected strategy to alleviate the limitation of traditional photodynamic therapy by biotinylation of three photosensitizers (two fluorescein-based photosensitizers and the commercially available Protoporphyrin). The three biotiylated photosensitizers named as compound 1, 2 and 3, exhibit impressive ability in generating both superoxide anion radicals and singlet oxygen. Moreover, compound 1 can be activated upon low-power white light irradiation with stronger ability of anion radicals generation than the other two. The excellent combinational Type I / Type II photodynamic therapy performance has been demonstrated with the photosensitizers 1. This work presents a universal protocol to provide tumor-targeting ability and enhance or trigger the generation of anion radicals by biotinylation of Type II photosensitizers against tumor hypoxia.

Liposome-Based Nanoencapsulation of a Mitochondria-Stapling Photosensitizer for Efficient Photodynamic Therapy.

Mitochondria-targeting photodynamic therapy (PDT) can block mitochondrial function and trigger the inherent proapoptotic cascade signal of mitochondria, which has been considered to have the potential to amplify the efficiency of PDT. However, the dynamic change of mitochondrial membrane potential (MMP) makes most cationic photosensitizers easily fall off from the mitochondria, which greatly limits the efficiency of PDT. Here, we have developed a smart liposome encapsulation method based on a mitochondria-stapling photosensitizer for efficient theranostic photodynamic therapy. The stapling photosensitizer can be covalently bound inside mitochondria via two reaction sites without a falloff effect, regardless of the change of MMP. As a result, the liposome-based nanophotosensitizer showed a high efficiency of PDT (IC50 = 0.98 µM) under 630 nm light. At the same time, the nanophotosensitizer had fluorescence imaging-guided ability to monitor abnormal mitochondrial morphology during PDT. Importantly, the results of mice experiments also showed that the liposome-based nanophotosensitizer possessed excellent antitumor PDT activity because the released photosensitizer can stay inside mitochondria during the whole process of PDT.

Prognostic factors and therapeutic effects of different treatment modalities for colorectal cancer liver metastases.

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignant tumors in China, and the liver is the most common metastatic site in patients with advanced CRC. Hepatectomy is the gold standard treatment for colorectal liver metastases. For patients who cannot undergo radical resection of liver metastases for various reasons, ablation therapy, interventional therapy, and systemic chemotherapy can be used to improve their quality of life and prolong their survival time. AIM: To explore the prognostic factors and treatments of liver metastases of CRC. METHODS: A retrospective analysis was conducted on 87 patients with liver metastases from CRC treated at the Liaoning Cancer Hospital and Institute between January 2005 and March 2011. According to different treatments, the patients were divided into the following four groups: Surgical resection group (36 patients); ablation group (23 patients); intervention group (15 patients); and drug group (13 patients). The clinicopathological data and postoperative survival of the four groups were analyzed. The Kaplan-Meier method was used for survival analysis, and the Cox proportional hazards regression model was used for multivariate analysis. RESULTS: The median survival time of the 87 patients was 38.747 ± 3.062 mo, and the 1- and 3-year survival rates were 87.5% and 53.1%, respectively. The Cox proportional hazards model showed that the following factors were independent factors affecting prognosis: The degree of tumor differentiation, the number of metastases, the size of metastases, and whether the metastases are close to great vessels. The results of treatment factor analysis showed that the effect of surgical treatment was better than that of drugs, intervention, or ablation alone, and the median survival time was 48.83 ± 4.36 mo. The drug group had the worst prognosis, with a median survival time of only 13.5 ± 0.7 mo (P < 0.05). For patients with liver metastases of CRC near the great vessels, the median survival time (27.3 mo) of patients undergoing surgical resection was better than that of patients using other treatments (20.6 mo) (P < 0.05). CONCLUSION: Patients with a low degree of primary tumor differentiation, multiple liver metastases (number of tumors > 4), and maximum diameter of liver metastases > 5 cm have a poor prognosis. Among drug therapy, intervention, ablation, and surgical treatment options, surgical treatment is the first choice for liver metastases. When liver metastases are close to great vessels, surgical treatment is significantly better than drug therapy, intervention, and ablation alone.

Clinical efficacy of gemcitabine and cisplatin-based transcatheter arterial chemoembolization combined with radiotherapy in hilar cholangiocarcinoma.

BACKGROUND: Radical surgical resection is regarded as the best treatment for hepatic hilar cholangiocarcinoma. However, 60%-70% of patients have lost the chance of surgery at the time of diagnosis. Simple biliary stent or drainage tube placement may fail in a short time due to tumor invasion or overgrowth, bile accumulation, or biofilm formation. Effective palliative treatments to extend the effective drainage time are of great significance for improving the quality of life of patients and changing the prognosis of patients. AIM: To investigate the clinical efficacy of gemcitabine and cisplatin-based transcatheter arterial chemoembolization (TACE) combined with radiotherapy in hilar cholangiocarcinoma. METHODS: A retrospective analysis was conducted on patients clinically diagnosed with hilar cholangiocarcinoma from June 2014 to January 2017 at the Liaoning Provincial Cancer Hospital. Patients were evaluated by specialists, and those who were not suitable for surgery or unwilling to undergo surgery and met the inclusion criteria were included in the study. There were a total of 72 patients (34 males and 38 females) with an average age of 59.9 years (range, 40-72 years). According to percutaneous transhepatic biliary angiography and the patients' wishes, stent implantation or biliary drainage tube implantation was used to relieve biliary obstruction. The patients were divided into either a control group or a combined treatment group according to their follow-up treatment. The control group consisted of a total of 35 patients who received simple biliary drainage tube placement and biliary stent implantation (7 patients with bilateral stents and 6 with a unilateral stent) and 22 patients receiving biliary drainage tube placement alone. The combined treatment group received TACE and extracorporeal radiotherapy after biliary drainage or biliary stent implantation and consisted of a total of 37 patients, including 21 patients receiving combined treatment after biliary stent placement (14 patients with bilateral stents and 7 with a unilateral stent) and 16 undergoing combined therapy after implanting the biliary drainage tube. In the combination treatment group, the TACE chemotherapy regimen employed gemcitabine and cisplatin, and the embolic agent was iodized oil. A particular dose was determined according to the patient's body surface area and the tumor staining indicated by DSA. In vitro radiotherapy was performed with intensity-modulated radiotherapy or three-dimensional conformal radiotherapy at an average dose of 48.3 Gy. Both groups were followed from stent implantation or drainage tube implantation until the patient quitted or died. The median length of follow-up observation was 13 mo. The differences in overall survival time and the effect of different jaundice reducing methods (single stent, double stent, or biliary drainage) on the patency time and survival time of biliary stents were compared between the two groups; the related factors affecting overall survival time were analyzed. RESULTS: The median survival time of the control group was 10.5 mo; the median survival time of patients with biliary stent implantation and those with percutaneous biliary drainage was 9.6 mo and 11.4 mo, respectively, and there was no statistically significant difference between them. The median survival time of the combined treatment group was 20.0 mo, which was significantly higher than that of the control group (P < 0.05). Among patients in the combined treatment group, the median survival time of patients who underwent biliary stent implantation and those who accepted percutaneous biliary drainage before the combination therapy was 19.5 mo and 20.1 mo, respectively, and there was no significant difference between them. In the combination treatment group, the mean time of median stent patency was 15.6 mo, which was significantly higher than that of the control group (7.0 mo; P < 0.05). The independent factors affecting survival time included age, whether to receive combination therapy, percutaneous biliary drainage tube implantation, and Bismuth-Corlette classification as type IV. CONCLUSION: Gemcitabine and cisplatin-based TACE combined with radiotherapy can prolong the survival of patients with hilar cholangiocarcinoma. Independent predictors of survival include selection of combination therapy, Bismuth-Corlette classification as type IV, selection of percutaneous biliary drainage tube implantation, and age.