The exact outcome of changed microbial diversity has not been elucidated, but studies have previously shown that an increase in α-diversity is often associated with improved survival and therapeutic consequences in several cancers (e.g., cervical cancer) by increasing the tumor infiltration of CD4+ lymphocytes as well as activated subsets of CD4 cells expressing ki67+ and CD69+.199 The growth of lung tumors is related to an increase in the number of bacteria and changes in bacterial composition in the airway. Here, CD4 is linked to cancer.