[The effect of hematoporphyrin photodynamic therapy on the growth of monoclonal cancer cells].

Three cloned esophageal cancer cell lines, Cu3, Cu4 and Cu6, were established from Eca109 cancer cells, and four cloned esophageal cancer cell lines, Ct1, Ct2, Ct5 and Ct7, were established from Eca109 cancer cells after hematoporphyrin photodynamic therapy. The propagation rate of Cu3, Cu4 and Cu6 was higher than Ct5 and Ct7 before 21 generations, demonstration an anti-propagation effect of hematoporphyrin dynamic therapy on cloned cancer cells. The propagation rate of Ct5 and Ct7 cells was partially recovered after 35 and 27 generations respectively. This was a long term effect of photodynamic therapy. A second course of hematoporphyrin photodynamic therapy was given to the 35th and 27th generations of Ct5 and Ct7 cells, and as a result the propagation rates obviously decreased as compared to the first treatment: thus, a cumulative therapeutic effect was shown. It is suggested that for better cancerocidal effect, continual photodynamic therapy is needed clinically. The shorter the interval between course, the better the therapeutic effect.