MRTFB and sarcoma: The analysis of integration sites has shown that HIV-1 integration occurs predominantly in specific genes encoding proteins involved in cell proliferation (such as BACH2) [61,62], cancer (such as MKL2 and HN1L, two genes implicated in sarcomas and non-small cell lung cancer, respectively) [61,63,64,65], chromatin modification (such as KANSL1) [61,66], and pre-mRNA splicing (such as PRPF6) [61,67].