HOTTIP and pachyonychia congenita: Compared with healthy controls, salivary HOTAIR and PVT1 showed significant over-expression in PC patients (both p values were < 0.001), but there were no significant differences of salivary H19, HOTTIP, and MALAT1 levels between the two groups (p values were 0.149, 0.630 and 0.639, respectively).