In our own studies using a mouse model of carcinogen [3-methylcholanthrene (MCA)]-induced fibrosarcomas (18, 19, 29), we found that depleting Foxp3+ Tregs resulted in the development of PNAd+ vessels in some tumors where they are associated with a higher number of tumor-infiltrating lymphocytes (TIL) and control of tumor growth. Here, NTAN1 is linked to fibrosarcoma.