Photodynamic therapy (PDT) is a method of cancer treatment that leads to the disintegration of cancer cells and has developed significantly in recent years. The clinically used photosensitizers are primarily porphyrin, which absorbs light in the red spectrum and their absorbance maxima are relatively short. This review presents group of compounds and their derivatives that are considered to be potential photosensitizers in PDT. Cyanine dyes are compounds that typically absorb light in the visible to near-infrared-I (NIR-I) spectrum range (750–900 nm). This meta-analysis comprises the current studies on cyanine dye derivatives, such as indocyanine green (so far used solely as a diagnostic agent), heptamethine and pentamethine dyes, squaraine dyes, merocyanines and phthalocyanines. The wide array of the cyanine derivatives arises from their structural modifications (e.g., halogenation, incorporation of metal atoms or organic structures, or synthesis of lactosomes, emulsions or conjugation). All the following modifications aim to increase solubility in aqueous media, enhance phototoxicity, and decrease photobleaching. In addition, the changes introduce new features like pH-sensitivity. The cyanine dyes involved in photodynamic reactions could be incorporated into sets of PDT agents.

Modifications of the composition or organization of the cancer cell membrane seem to be a promising targeted therapy. This approach can significantly enhance drug uptake or intensify the response of cancer cells to chemotherapeutics. There are several methods enabling lipid bilayer modifications, e.g., pharmacological, physical, and mechanical. It is crucial to keep in mind the significance of drug resistance phenomenon, ion channel and specific receptor impact, and lipid bilayer organization in planning the cell membrane-targeted treatment. In this review, strategies based on cell membrane modulation or reorganization are presented as an alternative tool for future therapeutic protocols.

Background/Aim: There is no satisfactory treatment of glioblastoma multiforme, a highly invasive brain tumor. The aim of this study was to analyze the cytotoxic effects of curcumin (CUR) alone and as a photosensitizer on glioblastoma cells. Materials and Methods: The SNB-19 cells where incubated for 2 and 24 h with 5-200 mM of CUR. The cells were radiated with blue light (6 J/cm²) and compared to non-irradiated ones. The effects of treatment were assessed by measuring mitochondrial activity with the MTT method and apoptosis progression by flow cytometry. To investigate CUR uptake, fluorescence imaging of cells was performed. Results: Photosensitization of CUR decreased the EC₅₀ 6.3 times when the incubation time was 2 h and over 90% of cells underwent apoptosis. The study of the uptake of CUR showed that during the 2 h, CUR was placed in the entire cytoplasm, and over time, its amount decreased and localized in the subcellular compartments. Conclusion: CUR is a promising medicament that can be used as a photosensitizer in photodynamic therapy for glioma treatment.

The mismatch repair system is critical for correcting base–base mismatches and insertion-deletion loops during DNA replication. Deficiencies in MMR (due to mutations in MLH1, MSH2, MSH6, or PMS2) lead to microsatellite instability and contribute to the development of various cancers, such as Lynch syndrome-related colorectal cancer and sporadic tumors. This review will delve into the molecular basis of MMR deficiency. Additionally, the review will cover diagnostic approaches for detecting MSI and MMR deficiency, including next-generation sequencing and PCR-based methods. The implications for treatment will be discussed, emphasizing immune checkpoint inhibitors (e.g., pembrolizumab) that target tumors with high mutational burdens due to MMR deficiency, as well as novel therapeutic approaches like synthetic lethality exploiting DNA repair vulnerabilities.