KISS1 and osteosarcoma: MNX1-AS1 could promote osteosarcoma proliferation and invasion via inhibiting KISS1, migration and invasion of esophageal squamous cell carcinoma by upregulating IGF2, progression of cervical cancer through activating the MAPK pathway, and MNX1-AS1 overexpression promotes the invasion and metastasis of gastric cancer through repressing CDKN1A.