Dihydroartemisinin administration improves the effectiveness of 5-aminolevulinic acid-mediated photodynamic therapy for the treatment of high-risk human papillomavirus infection

Photodynamic Therapy Combined with Ferroptosis Is a Synergistic Antitumor Therapy Strategy

Ferroptosis is a programmed death mode that regulates redox homeostasis in cells, and recent studies suggest that it is a promising mode of tumor cell death. Ferroptosis is regulated by iron metabolism, lipid metabolism, and intracellular reducing substances, which is the mechanism basis of its combination with photodynamic therapy (PDT). PDT generates reactive oxygen species (ROS) and 1O2 through type I and type II photochemical reactions, and subsequently induces ferroptosis through the Fenton reaction and the peroxidation of cell membrane lipids. PDT kills tumor cells by generating excessive cytotoxic ROS. Due to the limited laser depth and photosensitizer enrichment, the systemic treatment effect of PDT is not good. Combining PDT with ferroptosis can compensate for these shortcomings. Nanoparticles constructed by photosensitizers and ferroptosis agonists are widely used in the field of combination therapy, and their targeting and biological safety can be improved through modification. These nanoparticles not only directly kill tumor cells but also further exert the synergistic effect of PDT and ferroptosis by activating antitumor immunity, improving the hypoxia microenvironment, and inhibiting the tumor angiogenesis. Ferroptosis-agonist-induced chemotherapy and PDT-induced ablation also have good clinical application prospects. In this review, we summarize the current research progress on PDT and ferroptosis and how PDT and ferroptosis promote each other.

Photodynamic therapy for precancer diseases and cervical cancer (review of literature)

The paper presents the results of literature data analysis on the main directions of precancerous diseases of the cervix uteri and cervical cancer treatment. Side effects following surgery or radiation treatment can lead to structural deformities, scarring, hyperpigmentation, systemic side effects, and destruction of normal tissue. In addition, the use of traditional methods of treatment can cause multidrug resistance, which will lead to ineffective treatment and the development of a relapse of the disease. To avoid toxicity and reduce side effects, alternative treatment strategies have been proposed. Photodynamic therapy (PDT) is a promising organ-preserving highly selective method for treating cervical neoplasia, which includes two stages: the introduction of a photosensitizer and local exposure to directed light radiation. A number of studies have demonstrated the high clinical efficacy of this method in the treatment of patients with cervical neoplasia and carriage of human papillomavirus infection without adverse consequences for fertility. The use of PDT contributes to the successful outcome of the treatment of pathological foci on the mucous membrane of the cervix, the effectiveness and safety of the method is ensured by the selective effect on tissues. In the course of treatment, normal surrounding tissues are not damaged, there is no gross scarring and stenosis of the cervical canal, thereby PDT allows maintaining the normal anatomical and functional characteristics of the cervix.

Dihydroartemisinin: A Potential Drug for the Treatment of Malignancies and Inflammatory Diseases

Dihydroartemisinin (DHA) has been globally recognized for its efficacy and safety in the clinical treatment of malaria for decades. Recently, it has been found that DHA inhibits malignant tumor growth and regulates immune system function in addition to anti-malaria. In parasites and tumors, DHA causes severe oxidative stress by inducing excessive reactive oxygen species production. DHA also kills tumor cells by inducing programmed cell death, blocking cell cycle and enhancing anti-tumor immunity. In addition, DHA inhibits inflammation by reducing the inflammatory cells infiltration and suppressing the production of pro-inflammatory cytokines. Further, genomics, proteomics, metabolomics and network pharmacology of DHA therapy provide the basis for elucidating the pharmacological effects of DHA. This review provides a summary of the recent research progress of DHA in anti-tumor, inhibition of inflammatory diseases and the relevant pharmacological mechanisms. With further research of DHA, it is likely that DHA will become an alternative therapy in the clinical treatment of malignant tumors and inflammatory diseases.

Mechanism of a new photosensitizer (TBZPy) in the treatment of high-risk human papillomavirus-related diseases

BACKGROUND

High-risk human papillomavirus infection is closely related to the development of several diseases, including cervical cancer and condyloma acuminatum. We recently designed a new photosensitizer, 1-triphenylaminebenzo[c][1,2,5]thiadiazole-4-yl)styryl)-1-methylpyridin-1-ium iodide salt (TBZPy), which shows good photodynamic properties. In this study, we explored the mechanism of action of the TBZPy photosensitizer and its potential application in the treatment of high-risk human papillomavirus-related diseases.

METHODS

HeLa cells (infected by the high-risk human papillomavirus strain HPV18) were treated with TBZPy-photodynamic therapy (PDT). Cell viability, production of reactive oxygen species, apoptosis, and mitochondrial membrane depolarization were evaluated using cell counting kit-8, immunofluorescence, and flow cytometry assays, respectively. Expression levels of the anti-apoptotic proteins Bcl-2 and Bcl-X_L; pro-apoptotic proteins Bax, cytochrome C, cleaved caspase 3, and cleaved caspase 9; and the mitochondrial stress protein heat shock protein 60 were examined by western blotting.

RESULTS

TBZPy-PDT inhibited the viability and promoted reactive oxygen species production, lactate dehydrogenase release, and apoptosis of HeLa cells in vitro. TBZPy-PDT also promoted the loss of mitochondrial membrane potential, downregulated the expression of anti-apoptotic proteins, and upregulated the expression of pro-apoptotic proteins. Moreover, TBZPy-PDT downregulated the expression of the human papillomavirus E6 and E7 proteins.

CONCLUSION

Our study demonstrates the effectiveness of TBZPy-PDT against human papillomavirus-related diseases. These findings provide a foundation for using this novel photosensitizer to treat diseases associated with high-risk human papillomavirus infection.