New targets and drugs in cancer chemotherapy

CypA: A Potential Target of Tumor Radiotherapy and/or Chemotherapy

Cyclophilin A (CypA) is a ubiquitous and highly conserved protein. CypA, the intracellular target protein for the immunosuppressant cyclosporine A (CsA), plays important cellular roles through peptidyl-prolyl cis-trans isomerase (PPIase). Increasing evidence shows that CypA is up-regulated in a variety of human cancers. In addition to being involved in the occurrence and development of multiple tumors, overexpression of CypA has also been shown to be strongly associated with malignant transformation. Surgery, chemotherapy and radiotherapy are the three main treatments for cancer. Chemotherapy and radiotherapy are often used as direct or adjuvant treatments for cancer. However, various side effects and resistance to both chemotherapy and radiotherapy bring great challenges to these two forms of treatment. According to recent reports, CypA can improve the chemosensitivity and/or radiosensitivity of cancers, possibly by affecting the expression of drug-resistant related proteins, cell cycle arrest and activation of the mitogen-activated protein kinase (MAPK) signaling pathways. In this review, we focus on the role of CypA in cancer, its impact on cancer chemotherapeutic and radiotherapy sensitivity, and the mechanism of action. It is suggested that CypA may be a novel potential therapeutic target for cancer chemotherapy and/or radiotherapy.

Preclinical studies for the combination of paclitaxel and curcumin in cancer therapy (Review)

Cancer is one of the most common causes of death and remains the first in China and the second in the US. The common treatments for cancer include surgery, radiation, chemotherapy, targeted therapy and immunotherapy, while chemotherapy remains one of the most important treatments. However, the efficacy of chemotherapy is limited due to drug induced-toxicities and resistance, particularly multiple drug resistance (MDR). Therefore, discovery and development of novel therapeutic drugs and/or combination therapy are urgently needed to reduce toxicity and improve efficacy. Paclitaxel has been widely used to treat various cancers including cervical, breast, ovarian, brain, bladder, prostate, liver and lung cancers. However, its therapeutic efficacy is limited and MDR is a major obstacle. Recently, numerous preclinical studies have shown that the combination of paclitaxel and curcumin may be an ideal strategy to reverse MDR and synergistically improve their therapeutic efficacy in cancer therapy. This review mainly focuses on the current development and progress of the combination of paclitaxel and curcumin in cancer therapy preclinically.

Recent developments in cancer chemotherapy oriented towards new targets

Malignant diseases are one of the major causes of death in the western world. Patients are treated by surgery, radiation and chemotherapy. Chemotherapeutic treatment is used to decrease the tumour burden and to eliminate malignant cells. However, in most cases, resistance against chemotherapy develops. Therefore, there is a permanent need for new additional treatment strategies and chemotherapeutic combination regimens. In the present review article, the authors try to highlight the most promising approaches and summarise a selection of potential targets and compounds which might become alternative treatment options against malignant diseases. Due to the high number of scientific articles and the rapid developments in the area of cancer research, the authors can only mention a few selected targets and treatment options; however, the review focuses on new and notably important targets and compounds.

Cancer therapy: new targets for chemotherapy

The number two cause of mortality in developed countries is cancer. Despite the enormous effort put into cancer prevention, early diagnosis and treatment, it is likely that the incidence of the cancer morbidity and mortality will increase for the foreseeable future. This is due to various factors such as increased life expectancy, changes in environment and also the socio-economic situation around the world. Some cancer attracts more attention than others and increasingly epidemiological information is reaching the general public and is beginning to influence behavior. It is now well recognized that, for example, 1 of 8 women in the industrialized world will be diagnosed with breast cancer. Additionally, a strong correlation was established between lung cancer incidence and smoking and it is broadly accepted that the incidence of colon cancer is directly related to age and diet, and has been increasing over time. The current failure of preventive measures to significantly reduce the increasing incidence of these common tumors illustrates the importance of effective cancer treatment strategies, including chemotherapy. The combination of various anticancer drugs, given together with surgery and radiotherapy, gives hope to many patients. There has been recent evidence of improved therapeutic outcome with recent approaches and newer agents but for continuing effective chemotherapeutic treatment there is a need for a detailed understanding of their mechanisms of action and on the rationale of their application. This review attempts to provide up-to-date information regarding the development of new and innovative treatment strategies for cancer chemotherapy. Virtually, every year several of new targets for cancer therapy on both, cellular and molecular levels, are identified and new drugs enter not only clinical trials but also are included in well accepted and documented therapeutic protocols. As this review is in addition to our review published previously (Medical Principles and Practice 11, 2002, 117-125), we have tried to include new and innovative targets and drugs that attract attention at present. Although it is not possible to provide a complete list of all achievements and cover all work done in this field, we hope to be able to give some insight into this rapidly developing area.