<title>Study on the effects of low-energy laser irradiation on the development of mouse S180 ascites sarcoma in vivo</title>

Abstract

The antitumor effects of low-energy laser irradiation (LELI) are always the focus of scientific investigation. The purpose of this study was to test the effects of low-energy He-Ne laser irradiation on mouse S180 ascites sarcoma. After innoculating S180 sarcoma cells at the dosage of 1 x 10⁶ cells per mouse, five group of BALB/c mice were irradiated at the spot of one Harder's glands of the mouse eye for six days with five different dosages of 7.33, 11.00, 14.67, 22.00 and 29.33 J/cm² respectively. The antitumor effects were evaluated in two aspects: life prolongation ratio and ascites growth of tumor-bearing mice. The results showed that low energy He-Ne laser irradiation of 7.33, 11.00, 14.67, 22.00 and 29.33 J/cm² could inhibit the proliferation speed of S180 ascites sarcoma in <i>vivo</i>, and therefore could prolong the survival time of the tumor bearing mice in some degree. Moreover, the dosage of 14.67 J/cm² showed the most remarkable inhibiting effects among the four dosages, and the life prolongation ratio was up to 45.51%. On the contrary, the proliferation speed of S180 ascites sarcoma cells in <i>vivo</i> was accelerated by the large dosage of 29.33 J/cm² LELI and the survival time of the tumor bearing mice were remarkably shortened. Low energy He-Ne laser irradiation with proper dosages can inhibit the development of the mouse S180 ascites sarcoma, while too large dosage shows promotive effects.