The results of the present study revealed that ten cases out of thirteen of RCs (76.9%) showed immunopositive expression of laminin-1 at the basement membrane zone of the epithelial lining. This is in accordance with the results of Poomsawat et al. . Interestingly, the negative immunostaining for laminin-1 was observed in three RCs (23.1%) that showed severe inflammatory reaction in the connective tissue wall of the cysts. This result is in accordance to that reported by Furuyama et al.,  who stated that the ability of epithelial cells to form continuous basement membrane was lost in the presence of inflammatory cytokines which enhances the secretion of matrix metalloproteinase (MMP-9) and (MMP-2).
On the other hand, negative immunoexpression of laminin-1 was observed in eleven cases out of twelve cases of OKCs included in this study. This finding is in agreement with the results of Amorim et al., . In contrast Poomsawat et al.,  concluded that laminin-1 was expressed in RCs, dentigerous cysts and odontogenic keratocyst with different distribution patterns and intensity. Also, Gurgel et al.,  investigated the expression of laminin-1 in twenty cases of odontogenic keratocysts and found that laminin-1 was expressed in all cases.
Seven cases of the RCs included in the present study were immunopositive for Ki-67, which represent 53.8% of the total cases. The expression was confined mainly to the basal cells. Interestingly the surface area and the number of immunopositive cells increased with the severity of inflammation in the connective tissue. This could be explained on the assumption that chronic inflammatory reaction could act as stimulators causing epithelial proliferation. An explanation similar to that reported by Willoughby et al.  who concluded that mild inflammatory injury stimulates epithelial proliferation, whereas more severe inflammation depresses it, perhaps due to more extensive progenitor-cell damage.
Immunopositivity for Ki-67 was detected in all cases of KCOTs included in the study. The expression was mainly in the supra-basal cells, a finding similar to that reported by Kichi et al .
However, further studies utilizing a larger sample size and more advanced methodological tools are recommended due to limited number of cases included in this study.