Ru(II)-modified TiO2 nanoparticles for hypoxia-adaptive photo-immunotherapy of oral squamous cell carcinoma.

The alternations in the hypoxic and immune microenvironment are closely related to the therapeutic effect and prognosis of oral squamous cell carcinoma (OSCC). Herein, a new nanocomposite, TiO2@Ru@siRNA is constructed from a ruthenium-based photosensitizer (Ru) modified-TiO2 nanoparticles (NPs) loaded with siRNA of hypoxia-inducible factor-1α (HIF-1α). Under visible light irradiation, TiO2@Ru@siRNA can elicit both Type I and Type II photodynamic effects, which causes lysosomal damage, HIF-1α gene silencing, and OSCC cell elimination efficiently. As a consequence of hypoxia relief and pyroptosis induction, TiO2@Ru@siRNA reshapes the immune microenvironment by downregulation of key immunosuppressive factors, upregulation of immune cytokines, and activation of CD4+ and CD8+ T lymphocytes. Furthermore, patient-derived xenograft (PDX) and rat oral experimental carcinogenesis models prove that TiO2@Ru@siRNA-mediated photodynamic therapy significantly inhibits the tumor growth and progression, and markedly enhances cancer immunity. In all, this study presents an effective hypoxia-adaptive photo-immunotherapeutic nanosystem with great potential for OSCC prevention and treatment.

Ailanthus Altissima-derived Ailanthone enhances Gastric Cancer Cell Apoptosis by Inducing the Repression of Base Excision Repair by Downregulating p23 Expression.

Chemotherapy plays an irreplaceable role in the treatment of GC, but currently available chemotherapeutic drugs are not ideal. The application of medicinal plants is an important direction for new drug discovery. Through drug screening of GC organoids, we determined that ailanthone has an anticancer effect on GC cells in vitro and in vivo. We also found that AIL can induce DNA damage and apoptosis in GC cells. Further transcriptome sequencing of PDX tissue indicated that AIL inhibited the expression of XRCC1, which plays an important role in DNA damage repair, and the results were also confirmed by western blotting. In addition, we found that AIL inhibited the expression of P23 and that inhibition of P23 decreased the expression of XRCC1, indicating that AIL can regulate XRCC1 via P23. The results of coimmunoprecipitation showed that AIL can inhibit the binding of P23 and XRCC1 to HSP90. These findings indicate that AIL can induce DNA damage and apoptosis in GC cells. Meanwhile, AIL can decrease XRCC1 activity by downregulating P23 expression to inhibit DNA damage repair. The present study sheds light on the potential application of new drugs isolated from natural medicinal plants for GC therapy.

[GC-MS analysis and cytotoxic activity of the supercritical extracts from roots and stems of Zanthoxylum nitidum].

The volatile components of roots and stems of Zanthoxylum nitidum were investigated by supercritical fluid carbon dioxide extraction (SFE-CO2) and gas chromatography-mass spectrometry(GC-MS). Thirty-one and fifty-one compounds were identified in the supercritical extracts from roots and stems of Z. nitidum, respectively, and total twenty-seven compounds were the common constituents. Among them, the major constituents in root and stem supercritical extracts were spathulenol (18.49 and 26.18%), n-hexadecanoic acid (14.24% and 12.79%), ar-tumerone (6.95% and 8.88%), oleic acid (8.39% and 5.71%) and hexanoic acid (4.39% and 7.78%). The in-vitro MTT assay showed that the volatile components of roots and stems of Z. nitidum did not exhibited any cytotoxic activity against human cancer Huh-7 and normal IEC-6 cells. These results indicated the same nature of the volatile constituents in the root and stem of Z. nitidum. This investigation may provide further evidence for expansion of medicinal parts of Z. nitidum.