HLA-C and soft tissue sarcoma: For HLA-B, frequencies ranged from 0% in ependymoma to 31% (5 out of 16) in aHGG models, while the homozygosity frequencies of HLA-C ranged from 11% (2 out of 19) in neuroendocrine to 36% (12 out of 36) in bone and soft tissue sarcoma models (Figure 3B).