Role Of Survivin Antisense Oligonucleotides In The Treatment Of Drug Resistant Hepatic Cellular Cancer

BackgroundLiver cancer, a common malignant tumor, causes the increasing death rate, so for being ranked the third among the ones by cancers in our country. The surgical resection is the first choice to treat liver cancer, but with undesirable outcomes such as recurrence and metastasis, especially in advanced patients when they were definitely diagnosed. What's more, radical excision is more difficult to perform on the ones who can not endure the surgery due to the unfavorable location and depth of tumors so as to encroach on the importance vessels or organs and weak liver function. In spite of the progression of some comprehensive therapies such as focal injection of absolute alcohol, cryotherapy, radio frequency and microwave thermofixation, interventional radiotherapy, biotherapy, and so on, chemotherapy remains the main strategy and the prognosis is still unsatisfying in the main. Drug resistance is a great difficulty which leads to the poor therapeutic outcome. Along with the development of genetic techniques, gene therapy has become a spotlight of cancer treatment. With a great number of meaningful researches by a lot of researchers in this field, inspiring achievements have been made.Gene therapeutic methods for liver cancer include: 1) alteration of tumor biological behaviors with tumor-suppressing genes; 2) suicide gene therapy to improve the drug sensitivity; 3) application of tumor-related viruses; 4) immunogene therapy; 5) antisense gene therapy to induce tumor cell apoptosis, etc. The fifth method is a newcomer. The growth of tumor cells depends on the balance between the proliferation and the apoptosis, but in majority, the latter plays the dominant role. The disorder of apoptosis process, therefore, can prolong abnormally the cell survival time, facilitate the accumulation of genetic mutation and help to weaken the surveillance of immune system, thus participating in the progression of tumors. On the base of the above knowledge, the introduction of apoptosis activating genes into tumor cells or the inactivation of anti-apoptotic genes has been one of the gene therapies for tumors.