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Combined viral and photodynamic therapy for oncological diseases has great potential to treat aggressive tumors such as glioblastomas. A conjugate of vesicular stomatitis virus (VSV) with protoporphyrin IX was prepared, and its oncolytic effects were studied and compared to the effects of the individual components. The VSV showed an oncolytic effect on glioblastoma cell lines T98G and LN229 at a virus titer of 105 TCID50/mL. A VSV titer of 104 TCID50/mL was sufficient for neuroblastoma cell death. A study of the effect of VSV in tumor 3D cell modeling found that VSV had a clear viral cytopathic effect on spheroids of T98G and LN229 cells. Conjugation with the porphyrin significantly reduced the viral titer, but when irradiated, lysis of cells was observed. Photodynamic treatment of T98G and LN229 cells and spheroids with protoporphyrin IX as a photosensitizer also had a cytotoxic effect on cells and, to a lesser extent, on the tumoroids, as complete cell death was not achieved for the tumoroids. The combination therapy, which involved sequential photodynamic therapy using protoporphyrin IX as a photosensitizer and treatment with VSV, was shown to significantly enhance efficacy, resulting in complete cell death of both T98G and LN229 cells and tumoroids. The combination treatment allowed for the use of a lower viral titer (103–104 TCID50/mL) and a lower porphyrin concentration (0.5 μg/mL) to achieve a significant cytotoxic effect. As a result, the implementation of this combination therapy would likely lead to fewer side effects from the treatment. This study clearly demonstrated the excellent perspectives of combination therapy for the treatment of highly aggressive tumors such as glioblastomas. [ABSTRACT FROM AUTHOR]

Conjugated porphyrin dyads have valuable electron-optical properties that make them useful for a variety of applications. Two dyads of palladium(II) β-octaethylporphyrin linked with a butenyne bridge to nickel(II) meso-diphenylporphyrin and methyl pyropheophorbide-a were synthesized using the Sonogashira cross-coupling reaction. Both dyads exhibited optical properties considerably different from their corresponding components, which indicated strong electronic interaction between the units in the dyads in both the ground and excited states, providing fast energy flow between the chromophores. DFT calculations revealed the structural features of the dyads in interconnection with their electronic properties. Conjugation energy gain forced a decrease in the dihedral angle between the porphyrin plane and the linking carbon–carbon double bond, although at the expense of distortion of the diphenylporphyrin ring. Electron transitions upon excitation comprise molecular orbitals centered on both chromophores, and their interaction led to an emerging new bathochromically shifted Soret band component at 460 nm. The palladium porphyrinate–chlorin dyad exhibits luminescence properties in the red visible range at room temperature and phosphorescence in the near-infrared (NIR) range at 77 K. In contrast, the palladium–nickel porphyrinate dyad does not emit light but absorbs light more efficiently across the entire visible spectrum. Both dyads feature broad and strong absorption representing panchromatic-like dyes. These dyads could be useful as potential photosensitizers for solar light conversion devices. [ABSTRACT FROM AUTHOR]