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    Modulation of heat shock protein expression and cytokine levels in MCF‐7 cells through photodynamic therapy
    (Springer-Verlag London Ltd.) Santos, Mariela Inês Batista dos; Godoi, Bruno Henrique; Silva, Newton Soares da; Oliveira, Luciane Dias de; Ramos, Lucas de Paula; Cintra, Ricardo Cesar; Pacheco‐Soares, Cristina
    In this study, we assess the impact of photodynamic therapy (PDT) using aluminum phthalocyanine tetrasulfonate (AlPcS4) on the viability and cellular stress responses of MCF-7 breast cancer cells. Specifically, we investigate changes in cell viability, cytokine production, and the expression of stress-related genes. Experimental groups included control cells, those treated with AlPcS4 only, light-emitting diode (LED) only, and combined PDT. To evaluate these effects on cell viability, cytokine production, and the expression of stress-related genes, techniques such as 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, enzyme-linked immunosorbent assays (ELISA), and real-time quantitative PCR (RT‒qPCR) were employed. Our findings reveal how PDT with AlPcS4 modulates mitochondrial activity and cytokine responses, shedding light on the cellular pathways essential for cell survival and stress adaptation. This work enhances our understanding of PDT's therapeutic potential and mechanisms in treating breast cancer.
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    Influence of Hydrocortisone in Chemotherapy and Photodynamic Therapy in HEp-2 Cells
    (Clinics in Oncology) Moraes, Carlos Dailton Guedes de Oliveira; Godoi, Bruno Henrique; Silva, Newton Soares da; Soares, Cristina Pacheco
    Aim: Cancer cells exhibit resistance to the immune response by regulating and altering the expression of mediators responsible for immune cell recruitment and disease progression. Cortisol is a natural hormone that may be associated with diseases such as cancer by stimulating stress and altering the cellular environment, favoring uncontrolled division and contributing to the inhibition of the immune response. In contrast, current therapeutic strategies do not present significant concerns about stress as a variable in cancer diagnosis and prognosis. The response of HEp-2 cells to stress induced by hydrocortisone and to treatment with Cyclophosphamide (CP) and Photodynamic Therapy (PDT) was analyzed. Methods: One mM of hydrocortisone induced stress in the cells. Cells were treated with 200 μg/ mL of cyclophosphamide or Aluminum Phthalocyanine Tetrasulfonate (AlPcS4) photosensitizer, LED irradiation (660 nm wavelength), intensity of 25 mW/cm2, power of 70 mW, fluence of 5 J/ cm2, characterizing the PDT. All groups were evaluated after 24 h and 48 h. Results: Assessment of stress-inducing mitochondrial activity and cell viability were performed, and the results demonstrated that hydrocortisone significantly altered the rate of cell death, compromising the effects of CP. Conclusion: However, hydrocortisone did not change the cell death rates caused by PDT, indicating the possibility of this hormone as an alternative therapy.