CD9 and lung cancer: In addition, in an in-situ lung tumor model established by lewis lung cancer (LLC) cells, both pre implantation of LLC cells transduced with CD9 adenovirus into the lungs and intratracheal administration of adenovirus encoding CD9 to tumor bearing mice reduced metastasis to mediastinal lymph nodes, suggesting that CD9 can prevent lymph node metastasis in primary lung cancer (24).