CCND1 and obesity due to melanocortin 4 receptor deficiency: Specifically, the relative protein expressions of lung cyclin D1 (0.818 ± 0.084 in HFD-fed C57BL/6J mice vs 0.528 ± 0.055 in SRC-fed C57BL/6J mice (P < 0.01) and 0.961 ± 0.093 in HFD-fed KKAy mice vs 0.538 ± 0.066 in SRC-fed KKAy mice (P < 0.01)) was significantly increased in HFD-fed mice, indicating overweight- or obesity-associated changes in cellular signaling.