The pro-inflammatory cytokine interleukin (IL)-6 (encoded by IL-6) participates in the modulation of proliferation, migration, invasion, growth, oncogenesis, malignant progression, therapeutic resistance, tumor microenvironment, and remodeling of PC cells and tumors; the cytokine is further correlated with the survival, prognosis, tumor aggressiveness and metastasis, and occurrence of cancer-related complications of patients with PC [81–86]. The gene discussed is IL6; the disease is pachyonychia congenita.