S100A7 and chronic obstructive pulmonary disease: However, the analysis of the correlation of S100A7/psoriasin mRNA expression with cigarette smoking (i.e., pack years; irrespective of health/COPD status) revealed a significant correlation in biopsies (Spearman r = 0.3266, P value = 0.026) but not in BAL fluid cells (Spearman r = 0.2934, P value = 0.0649, s.