HAND2 and breast cancer: Notably, we report for the first time specific co-expressed lncRNA pairs—MEG3–HOTAIRM1, MEG3–ADAMTS9-AS2, and MEG3–HAND2-AS1—as well as co-methylated pairs—HAND2-AS1–ADAMTS9-AS2, MEG3–HAND2-AS1, and HOTAIRM1–ADAMTS9-AS2—in BC, with consistent support from the GEPIA 2.0 database.