br showed no significant change at to weeks P
showed no significant change at to 5 weeks (P > 0.05); at 2 to 5 weeks, the average tumor inhibition rate of the Ad-VT treatment group was always higher than that of the other groups; the average tumor inhibition rate of the Ad-VT treatment group was significantly higher than that of the Ad-Mock treatment group and the control group at 3 to 5 weeks (P < 0.05); and at 5 weeks, the average tumor inhibition rate of the Ad-VT treatment group was as high as 66%, indicating that Ad-VT has a significant tumor inhi-bition effect.
After inducing subcutaneous tumors, the survival of each group of nude mice was continuously recorded. As shown in Fig. 9E, compared with the other 3 treatment groups (Ad-VT, Ad-T, and Ad-vp3), the mice of the control group and the Ad-mock treatment group began to die from about 23 days after the formation of the subcutaneous tumors, and their average survival times were about 30.8 days and 31.2 days, respectively, with no significant differ-ence (P > 0.05). Compared with the Ad-vp3 treatment group, the Ad-Mock treatment group, and the control r> Fig. 9. Effect of recombinant adenovirus on prostate cancer in a BALB/c nude mice model.
(A and B) The xenograft models were established via subcutaneous injection of PC-3-luc cells (1 £ 106/100 ml) into the right legs of the mice (n = 10 per group). Beginning after tumor formation, in vivo HC 030031 imaging was used to continuously monitor changes in tumor bioluminescence intensity. (C and
D) The length and width of the xenograft tumors were measured weekly using Vernier calipers from week, and continuously measured to 5 weeks. The % tumor
inhibition was calculated using the formula: (1 - treatment group tumor weight/control tumor weight) £ 100%. (E) After successfully establishing xenograft mod-els in nude mice, the survival of the mice was recorded every day, and 6 weeks was recorded continuously. The average % tumor inhibition of the Ad-VT group
group, the average survival time of the Ad-VT and Ad-T treatment groups was about 38 days and 36.1 days, respec-tively, that is, the survival time was significantly prolonged (P < 0.05). The survival time of the Ad-VT treated group
was longer than that of the Ad-T treated group, and at 42 days, the survival rate of the Ad-VT treated mice was 66.67%. This indicates that Ad-VT can increase the sur-vival rate of mice and significantly prolong their survival.
Cancer is one of the leading causes of death in developed and developing countries . Prostate cancer is the most common cancer among men. The genetic and epigenetic instability of tumor cell is potential driver for malignant pro-gression, which includes evasion of growth inhibition sig-nals, sustainment of replication, inhibition of cell death, stimulation of angiogenesis, cell migration and invasion, reprogramming of energy metabolism and avoidance of immune cells, which are known as "Hallmarks of Cancer" [37,38]. Currently, many researches are focusing on onco-lytic virus as a gene therapy for treatment of cancer, how-ever, the main challenge is to monitor and track the effects of gene therapy . With the introduction of molecular imaging technology, these challenges can be overcom. Molecular imaging technology has many advantages which enable to monitor various physiological and pathological changes in a noninvasive and real-time approach.
BLI is based on luciferase-labeled cells or DNA. In the presence of O2, Mg2+, and adenosine triphosphate, the expression product can catalyze the oxidation of fluorescein and release photons, which is a self-luminescence phenom-enon. It does not require excitation light, has high sensitiv-ity, and a low signal-to-noise ratio. It is used to detect subtle changes of deep tissue in a holistic and noninvasive manner, and can quantify the bioluminescence intensity and its correlation with cell number or tumor volume can be analyzed [40−42]. The most widely used is firefly lucif-erase, whose main advantages are: A very low level of luciferase can be detected with a simple instrument with high sensitivity; light emission can be detected in cuvettes, microplates, and petri dishes, and can be tested in vivo; and adenosine triphosphate is the energy currency of all living cells [43,44]. In the present study, the plasmid pGL4.51 was used to transfect cells to construct tumor cells that sta-bly expressed luciferase (PC-3-luc).
In this study, the relationship between the luminescence intensity of PC-3-luc cells and the number of cells was ana-lyzed using in vitro imaging experiments, which indicated that there is a linear relationship between the luminescence intensity and the number of cells, for which the correlation coefficient was R2 = 0.9982. Cell luminescence increased with the increase in cell number, indicating that the biolumi-nescence intensity in region of interest could reflect the number of cells in this region, and there was a positive cor-relation between the cell number and bioluminescence intensity, providing a cytological basis for establishing a tumor model that could be observed by the living imaging system. Subsequently, the biological characteristics of PC-3-luc cells and PC-3 cells were compared. The results showed that PC-3-luc cells and PC-3 cells have similar growth trends and cell cycles. In mice, PC-3-luc cells could be used to replace PC-3 cells to establish a tumor model, and the tumor growth and metastasis, and the antitumor drug effect, were studied through the living imaging system.