Single Local Interleukin@2 Treatment against Transplanted and Spontaneous Mammary Cancer

Immunotherapy is currently emerging mode of breast cancer therapy as efficacy of traditional therapies seems to reach plateau nowadays. First transplanted generation from non-SPF spontaneous BLRB mammary adenocarcinoma (MAC) were used as appropriate mouse model to examine whether single local interleukin-2 (IL-2) is efficient against mammary cancer. We showed that survival dynamics of syngeneic BLRB males with early emerging transplanted mammary cancer (short subclinical period) taken from naturally arisen female mammary carcinoma could be significantly improved by a single IL-2 treatment (2,5 × 10 IU per mouse) applied locally two weeks after MAC cell inoculation. However, the same IL-2 therapy mode applied to later emerging tumors (long subclinical period) of the same average size of 5 mm as late as eighth week after tumor cell inoculation notably shortened the survival of tumor-bearing mice. So, both the fundamental significance and applied implications of biphasic IL-2 effect on mammary cancer growth was shown.