AbstractThe expression of 72KD type Ⅳ collagenase and distribution of type Ⅳ coolagen in 22 cases of gastricmucinous carcinoma were studied by immunochistochemical technique and the three types of mucinous cell ingastric mucinous carcinoma were also studied by electronmicroscopy

The results show that intense cytoplas-mic immunostaining of the enzyme could be found in type Ⅱ cancer cell

while in type Ⅰ and Ⅲ cancer cells

aweak expression of the enzyme. The immunostaining of type Ⅳ collagen is negative around the diffuse cancercells. The results indicate that production of 72KD type Ⅳ collagenase is related to differentiation of muci-nous cell carcinoma. Mucinous cancer cells are able to elevate and secrete type Ⅳ collagenase to degrade hase-ment membrane collagen

thus facilitating cancer to infiltrate into the stroma.