MUC1 and soft tissue sarcoma: Seven genes (LPP‐AS2, MUC1, GAB2, hsa‐let‐7i‐5p, hsa‐let‐7f‐5p, hsa‐miR‐101‐3p, andhsa‐miR‐1226‐3p) in a recurrent soft tissue sarcoma‐specific ceRNA network associated with recurrence and survival were identified based on the TCGA database.35