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Photodynamic therapy (PDT) induces cancer cell death by generating reactive oxygen species (ROS). In this process, photosensitizers accumulate in cancer cells irradiated by laser light of a specific wavelength, leading to ROS generation. Verteporfin (VP), a second-generation photosensitizer, is used in PDT for age-related macular degeneration. However, the antitumor effects of VP-PDT remain poorly defined. This study investigated the antitumor effects of VP-PDT on esophageal cancer (EC) cell lines in vitro. Two types of EC cell lines, the KYSE30 cell line, derived from highly differentiated esophageal carcinoma, and the KYSE170 cell line, derived from moderately differentiated carcinoma, were used in this study. VP-PDT exerted effective anticancer effects in both cell lines. Our results revealed that the low-density lipoprotein receptor, albumin receptor, and heme carrier protein-1 in VP uptake were not involved in VP uptake. However, cells rich in intracellular glutathione were resistant to VP-PDT. Our study outcomes suggest that lowering intracellular glutathione via a glutathione synthesis inhibitor or sulfasalazine can increase the effectiveness of VP-PDT-mediated anticancer effects.

Protamine, one of the nucleoproteins, is contained in the sperm of fishes and is a linear polypeptide with many arginine (Arg) residues. The basic polypeptide chain can behave as the proton acceptor site in the acid-base composite material. Therefore, we prepared the composite material by the mixing of the basic protein, protamine, and the acidic molecule, methanediphosphonic acid (MP). The protamine-MP composite materials formed the acid-base complex by the electrostatic interaction between the protonated guanidino group in Arg residue and the deprotonated phosphonic acid group in the MP molecule. In addition, the protamine-MP composite material showed the anhydrous proton conductivity of 9.1 × 10−4 S cm−1 at 160 °C in the flowing dry nitrogen. The proton conducting mechanism in the protamine-MP composite material depended on the proton transfer to the proton defect site in the MP molecule without the need of diffusible molecules, such as the oxonium ion.

The aim of this study was to investigate the feasibility of ablative margin (AM) grading by magnetic resonance imaging (MRI) with Gd-EOB-DTPA administered prior to radiofrequency ablation (RFA), and to identify factors for achieving a sufficient AM and predictors for local tumor progression.A total of 124 hepatocellular carcinomas (HCCs) were treated by RFA after Gd-EOB-DTPA administration. MRI and enhanced CT were performed within seven hours and one month after RFA. The AM assessment was categorized using three grades: AM (+), low-intensity area with continuous high-intensity rim; AM zero, low-intensity area with discontinuous high-intensity rim; and AM (-), low-intensity area extends beyond the high-intensity rim. Patients were followed and local tumor progression was observed.AM (+), AM zero, AM (-), and indeterminate were found in 34, 33, 26, and 31 nodules, respectively. The overall agreement rate between MRI and enhanced CT for the diagnosis of AM was 56.8%. The κ coefficient was 0.326 (p0.001), indicating moderate agreement. Multivariate logistic regression analysis showed that a significant factor for the achievement of AM (+) on MRI was no contiguous vessels. The cumulative local tumor progression rates (0% at 1, 2, and 3 years) in 33 AM (+) nodules were significantly lower than those (3.6%, 11.5%, and 18.3% at 1, 2, and 3 years respectively) in 32 AM zero nodules. A multivariate Cox proportional hazards model identified tumor size as an independent predictor for local tumor progression.Gd-EOB-DTPA-MRI enabled an early assessment of RFA effectiveness in the majority ofHCC nodules. Local tumor progression was not detected in AM (+) nodules during the follow-up.

This study investigated whether contrast-enhanced sonography can accurately predict the ablated area by radiofrequency ablation using virtual sonography by computed tomography as a gold standard. Thirty-one hepatocellular carcinoma nodules were treated by radiofrequency ablation and then examined. The defect of contrast-enhanced sonography (puncture direction: r=.868, P