RESUMO
BACKGROUND: In our previous study, Cu(sal)phen was found to have anti-tumor effects, yet its precise mechanism remains unknown. Research has shown that dying tumor cells release damage-associated molecular patterns (DAMPs) to promote anti-tumor immune response. Therefore, we have further explored the effects and potential molecular mechanisms of Cu(sal)phen-induced immunogenic cell death (ICD) in colorectal cancer (CRC). METHODS: ELISA and flow cytometry were used to detect the effects of Cu(sal)phen treatment on ICD markers. The molecular mechanisms of Cu(sal)phen-induced ICD were investigated through the detection of endoplasmic reticulum stress (ERS) and reactive oxygen species (ROS) in vitro using Western blot and flow cytometry. Additionally, a mouse model was constructed to study the effects of Cu(sal)phen on immune cells and anti-tumor-related cytokines in vivo. RESULTS: Cu(sal)phen induced the release of calreticulin (CRT), adenosine triphosphate (ATP) and high mobility group box 1 (HMGB1), the main molecular markers of ICD, by promoting the accumulation of ROS and inducing ERS. Furthermore, Cu(sal)phen promoted the maturation of dendritic cells (DCs) and activation of CD8+T cells, as well as the secretion of interleukin-12 (IL-12) and interferon-γ (IFN-γ), while downregulating transforming growth factor-ß (TGF-ß) levels, thereby activating the anti-tumor immune response. CONCLUSION: Cu(sal)phen has the potential to induce ICD in tumors and activate the adaptive immune response to achieve anti-tumor effects. This makes Cu(sal)phen a promising candidate for the treatment of CRC.
Assuntos
Neoplasias Colorretais , Cobre , Estresse do Retículo Endoplasmático , Morte Celular Imunogênica , Fenantrolinas , Espécies Reativas de Oxigênio , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/imunologia , Animais , Morte Celular Imunogênica/efeitos dos fármacos , Humanos , Camundongos , Fenantrolinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Salicilatos/farmacologia , Linhagem Celular Tumoral , Proteína HMGB1/metabolismo , Citocinas/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Calreticulina/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Complexos de Coordenação/farmacologiaRESUMO
Oxaliplatin (Oxa) is one of the most effective chemotherapeutic drugs used in the treatment of colorectal cancer (CRC). However, the use of this drug is associated with severe sideeffects and patients eventually develop resistance to Oxa. In recent years, copper complexes have been extensively investigated as substitutes for platinumbased drugs. Therefore, a number of copper complexes have also been developed for cancer therapy, such as copper (II) complex of salicylate phenanthroline [Cu(sal)(phen)]. In the present study, the antitumor activity and the related molecular mechanisms of Cu(sal)(phen) were examined in CRC cells. As compared with the chemotherapeutic drug, Oxa, Cu(sal)(phen) was more effective in inducing apoptosis and reactive oxygen species (ROS) production, and in decreasing mitochondrial membrane potential in the CRC cell lines, HCT116 and SW480. In addition, the expression of the apoptosisrelated proteins, Bcl2 and survivin, and those of the upstream regulators, pJAK2 and pSTAT5, were significantly decreased in the two cell lines following treatment with Cu(sal)(phen). Furthermore, the efficacy of the complex against CRC was found to be excellent in an animal model. The results of immunohistochemical analysis revealed that the expression levels of Bcl2, survivin and Ki67 in tumor tissues were decreased following Cu(sal)(phen) treatment. The antitumor mechanisms underlying Cu(Sal)(phen) treatment were the induction of ROS generation, the inhibition of the JAK2/STAT5 signaling pathway and the downregulation of the expression of antiapoptotic proteins, such as Bcl2 and survivin. On the whole, the findings of the present study indicated that Cu(sal)(phen) effectively inhibited the viability and proliferation of HCT116 and SW480 CRC cells; in the future, the authors aim to conduct further experiments in future studies to provide more evidence that supports the development of Cu(sal)(phen) as a therapeutic agent for CRC.
Assuntos
Antineoplásicos , Neoplasias Colorretais , Animais , Oxaliplatina/farmacologia , Cobre/farmacologia , Cobre/química , Cobre/metabolismo , Survivina/metabolismo , Fenantrolinas/farmacologia , Fenantrolinas/química , Fator de Transcrição STAT5/metabolismo , Fator de Transcrição STAT5/farmacologia , Salicilatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Antineoplásicos/farmacologia , Antineoplásicos/química , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Linhagem Celular TumoralRESUMO
In the present study, we investigated the antitumor effect and associated molecular mechanisms of the copper (II) complex of salicylate phenanthroline [Cu(sal)(phen)] against hepatocellular carcinoma (HCC). Cu(sal)(phen) inhibited the proliferation of HCC cells (HepG2 and HCC-LM9) and induced apoptosis of HCC cells in a dose-dependent manner by upregulating mitochondrial reactive oxygen species (ROS) production. The expression of the antiapoptotic proteins survivin and Bcl-2 was decreased, while the expression of the DNA damage marker γ-H2 AX and the apoptotic marker cleaved PARP was upregulated with Cu(sal)(phen) treatment. In vivo, the growth of HepG2 subcutaneous xenograft tumors was greatly attenuated by Cu(sal)(phen) treatment. Immunohistochemistry staining showed that the expression of survivin, Bcl-2, and Ki67 in the tumor was downregulated by Cu(sal)(phen). Toxicity experiments with BALB/c mice revealed that Cu(sal)(phen) is a relatively safe drug. Our results indicate that Cu(sal)(phen) possesses great potential as a therapeutic drug for HCC.