Pitchayuth Srisai

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype associated with radioresistance and limited treatment options. Titanium dioxide nanoparticles (TiO₂-NPs) have attracted attention as potential radiosensitizers because they can enhance radiation-induced oxidative stress. This study evaluated the radiosensitizing effects of BSA-adsorbed TiO₂-NPs in MDA-MB-231 TNBC cells exposed to clinically relevant 6 MV X-ray irradiation. FITC-based cellular association, as an indicator of potential nanoparticle uptake, metabolic activity, clonogenic survival, sensitizer enhancement ratio (SER), reactive oxygen species (ROS), γ-H2AX positivity, and apoptosis were assessed. Flow cytometric analysis showed that approximately 55% of cells were FITC-positive after 24 h of exposure, while approximately 90% metabolic activity was maintained at the selected concentration (25 µg/mL). Combined treatment significantly reduced the surviving fraction from 0.81 to 0.37 after 2 Gy irradiation and yielded SER values of 1.21 and 1.59 at SER₁₀ and SER₃₇, respectively. In addition, combined treatment produced the greatest increases in intracellular ROS generation, γ-H2AX positivity, and apoptosis compared with either treatment alone. These findings indicate that BSA-adsorbed TiO₂-NPs increase the radiosensitivity of TNBC cells under clinically relevant megavoltage irradiation and support their further evaluation as potential radiosensitizers for breast cancer radiotherapy.

Glioblastoma (GBM) is the most aggressive and treatment-resistant primary brain tumor in adults. Despite current multimodal therapies, including surgery, radiation, and temozolomide chemotherapy, patient outcomes remain poor. Enhancing tumor radiosensitivity through biocompatible nanomaterials could provide a promising integrative strategy for improving therapeutic effectiveness. This study aims to evaluate the potential of bovine serum albumin-coated copper oxide nanoparticles (BSA@CuO-NPs) to enhance radiosensitivity in U87-MG cells under clinically relevant X-ray irradiation. In brief, BSA@CuO-NPs were synthesized via carbodiimide crosslinking and characterized by DLS, SEM, and zeta potential analysis. U87-MG cells were treated with BSA@CuO-NPs alone or in combination with X-ray irradiation (2 Gy). Cytotoxicity was assessed using the MTT assay, while radiosensitization was evaluated through clonogenic survival analysis. Apoptosis induction and DNA damage were analyzed via Annexin V staining and γ-H2AX immunofluorescence, respectively. The results revealed that BSA@CuO-NPs showed good colloidal stability and biocompatibility compared with uncoated CuO-NPs. When combined with irradiation, BSA@CuO-NPs significantly decreased clonogenic survival (p < 0.05) and increased apoptotic cell death compared to irradiation alone. Immunofluorescence demonstrated increased γ-H2AX focus formation, indicating higher DNA double-strand breaks in the combination group. In conclusion, BSA@CuO-NPs enhance the effects of ionizing radiation by increasing DNA damage and apoptosis in U87-MG cells, indicating their potential as combined radiosensitizers. These results support further research into albumin-coated metal oxide nanoparticles as adjuncts to standard radiotherapy for the management of GBM. One challenge in this context is the effective delivery of nanoparticles to GBM. However, the stability of BSA@CuO-NPs in physiological solutions could help overcome this obstacle.

The white mulberry (Morus alba L.) is widely used as a medicinal plant in Asia. In this study, the bioactive compounds of ethanolic extracts of white mulberry leaves from the Sakon Nakhon and Buriram cultivars were evaluated. The ethanolic extracts of mulberry leaves from the Sakon Nakhon cultivar showed the highest total phenolic content of 49.68 mg GAE/g extract and antioxidant activities of 4.38 mg GAE/g extract, 4.53 mg TEAC/g extract, and 92.78 mg FeSO₄/g extract using 2,2 diphenyl-1-picrylhydrazyl (DPPH), 2,20-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays, respectively. The resveratrol and oxyresveratrol compounds in mulberry leaves were also investigated by high-performance liquid chromatography (HPLC). The mulberry leaf extracts from the Sakon Nakhon and Buriram cultivars showed oxyresveratrol contents of 1.20 ± 0.04 mg/g extract and 0.39 ± 0.02 mg/g extract, respectively, whereas resveratrol was not detected. It was also found that the potent anti-inflammatory properties of mulberry leaf extracts and its compounds, resveratrol and oxyresveratrol, suppressed the LPS-stimulated inflammatory responses in RAW 264.7 macrophage cells by significantly reducing nitric oxide production in a concentration-dependent manner. These compounds further inhibited interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) production and suppressed the mRNA and protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 macrophage cells. Therefore, it is established that mulberry leaf extract and its bioactive compounds contribute to its anti-inflammatory activity.

Epidemiologic studies have suggested an association between agrochemical exposure and risk of renal injury. Farmers face great risks to developing adverse effects. The most appropriate biomarker related to renal injury needs to be developed to encounter earlier detection. We aim to study the association between early renal biomarker and occupational herbicide exposure in maize farmers, Thailand. Sixty-four farmers were recruited and interviewed concerning demographic data, herbicide usage, and protective behavior. Two spot urines before (pre-work task) and after (post-work task) herbicide spraying were collected. To estimate the intensity of exposure, the cumulative herbicide exposure intensity index (cumulative EII) was also calculated from activities on the farm, type of personal protective equipment (PPE) use, as well as duration and frequency of exposure. Four candidate renal biomarkers including π-GST, sirtuin-1, mitochondrial DNA (mtDNA) were measured. Most subjects were male and mostly sprayed three herbicides including glyphosate-based herbicides (GBH), paraquat, and 2,4-dichlorophenoxyacetic acid (2,4-D). A type of activity in farm was mixing and spraying herbicide. Our finding demonstrated no statistical significance of all biomarker levels between pre- and post-work task urine. To compare between single and cocktail use of herbicide, there was no statistical difference in all biomarker levels between pre- and post-work task urine. However, the urinary mtDNA seems to be increased in post-work task urine. Moreover, the cumulative EII was strongly associated with change in mtDNA content in both ND-1 and COX-3 gene. The possibility of urinary mtDNA as a valuable biomarker was promising as a noninvasive benchmark for early detection of the risk of developing renal injury from herbicide exposure.