Novel silicon phthalocyanines with improved singlet oxygen generation by Sono-photochemical applications

Photodynamic therapy (PDT) is a clinically approved, minimally invasive therapeutic procedure that can exert a selective cytotoxic activity toward malignant cells. The procedure involves administration of a photosensitizing agent followed by irradiation at a wavelength corresponding to an absorbance band of the sensitizer. In the presence of oxygen, a series of events lead to direct tumor cell death, damage to the microvasculature, and induction of a local inflammatory reaction. Clinical studies revealed that PDT can be curative, particularly in early stage tumors. It can prolong survival in patients with inoperable cancers and significantly improve quality of life. Minimal normal tissue toxicity, negligible systemic effects, greatly reduced long-term morbidity, lack of intrinsic or acquired resistance mechanisms, and excellent cosmetic as well as organ function-sparing effects of this treatment make it a valuable therapeutic option for combination treatments. With a number of recent technological improvements, PDT has the potential to become integrated into the mainstream of cancer treatment. Show more

Developing an effective treatment for cancer is still a challenge. Despite great success with traditional cancer therapies, there are numerous disadvantages for conventional treatments such as systemic toxicity, low selectivity, drug resistance and potential long-term side effects. Recently, photodynamic therapy (PDT) has been widely applied in clinical settings. However, this approach suffers from the major shortcoming derived from the limited penetrability of visible light. Sonodynamic therapy (SDT) utilizing ultrasound combined with a sonosensitizer represents a novel noninvasive approach for cancer therapy, which is deemed to overcome the disadvantage of PDT. In this review, we extensively summarize the recent progress in the discovery of new sonosensitizers for SDT and discuss the future directions for the development of novel sonosensitizers. Show more

Circular RNAs (circRNAs), one type of non-coding RNA, were initially misinterpreted as nonfunctional products of pre-mRNA mis-splicing. Currently, circRNAs have been proven to manipulate the functions of diverse molecules, including non-coding RNAs, mRNAs, DNAs and proteins, to regulate cell activities in physiology and pathology. Accumulating evidence indicates that circRNAs play critical roles in tumor genesis, development, and sensitivity to radiation and chemotherapy. Radiotherapy and chemotherapy are two primary types of intervention for most cancers, but their therapeutic efficacies are usually retarded by intrinsic and acquired resistance. Thus, it is urgent to develop new strategies to improve therapeutic responses. To achieve this, clarification of the underlying mechanisms affecting therapeutic responses in cancer is needed. This review summarizes recent progress and mechanisms of circRNAs in cancer resistance to radiation and chemotherapy, and it discusses the limitations of available knowledge and potential future directions. Show more