Sono-photodynamic combination therapy: a review on sensitizers.

Cancer is characterized by the dysregulation of cell signaling pathways at several steps. The majority of current anticancer therapies involve the modulation of a single target. A tumor-targeting drug-delivery system consists of a tumor detection moiety and a cytotoxic material joined directly or through a suitable linker to form a conjugate. Photodynamic therapy has been used for more than 100 years to treat tumors. One of the present goals of photodynamic therapy research is to enhance the selective targeting of tumor cells in order to reduce the risk and extension of unwanted side-effects, caused by normal cell damage. Sonodynamic therapy is a promising new treatment for patients with cancer. It treats cancer with ultrasound and sonosensitive agents. Porphyrin compounds often serve as photosensitive and sonosensitive agents. The combination of these two methods makes cancer treatment more effective. The present review provides an overview of photodynamic therapy, sonodynamic therapy, sono-photodynamic therapy and the four sensitizers which are suitable candidates for combined sono-photodynamic therapy.

DNA damage induces the IL-6/STAT3 signaling pathway, which has anti-senescence and growth-promoting functions in human tumors.

IL-6 is a multifunctional cytokine that is important for immune responses, cell survival, apoptosis, and proliferation. However, little is known about the correlation between the IL-6 signaling pathway and DNA damage in human tumors. The present study demonstrates the role of the IL-6/STAT3 signaling pathway in human tumor cells exposed to DNA damage. Tumor cells exposed to DNA damage increase the expression and secretion of IL-6 and the phosphorylation of JAK1 and STAT3. The activation of the JAK1-STAT3 signaling pathway is inhibited by knockdown of gp130 or neutralization of soluble IL-6, implying that DNA damage induces the phosphorylation of JAK1 and STAT3 by autocrine IL-6. Interestingly, inhibition of the IL-6/STAT3 signaling pathway impairs the growth of tumor cells exposed to DNA damage and results in the induction of senescence. Therefore, the present study suggests that IL-6 inhibits senescence but promotes the survival and proliferation of tumor cells exposed to DNA damage through the activation of the JAK1-STAT3 signaling pathway.