Abstract: Objective:To investigate the expressions between musashi-1 (Msi-1) and caudalrelated homeodomain transcription 2 (CDX2) in gastric mucosa intestinal metaplasia.
 Methods:The retrospective cohort study was adopted. The clinicopathological data of 256 patients with gastritis ［46 of chronic nonatrophic gastritis (CNAG) and 210 of atrophic gastritis and intestinal metaplasia］ who were admitted to the Second Affiliated Hospital of Zhengzhou University from March 2009 to June 2013 were collected. The specimens were extracted by 2 endoscopy doctors and then were submitted for inspections. Pathological diagnosis was performed by independent filmreading of 3 pathologists. Endoscopy classification was conducted on the specimens of atrophic gastritis and intestinal metaplasia (focal uplift type, verrucous uplift type, flocculence incrassation or depression type). Mucus staining examination was also conducted on these for classification (Type Ⅰ, Ⅱ and Ⅲ).The specimens were tested by immunohistochemistry and immunofluorescence double staining tests. The comparison of count data was analyzed using chisquare test. Measurement data with normal distribution were presented as ±s. Comparison among groups was done using the oneway variance analysis and pairwise comparison was done by the LSD test.
Results:(1) Results of gastroscopy classification: among the 210 patients with atrophic gastritis and intestinal metaplasia, there were 65 of focal uplift type, 85 of verrucous uplift type and 60 flocculence incrassation or depression type. Classification of mucus staining examination: among the 210 specimens in patients with atrophic gastritis, type I was detected in 70 specimens, type Ⅱ in 75 specimens and type Ⅲ in 65 specimens. (2) The 204 specimens were examined by immunohistochemistry test, including 36 of CNAG and 168 of atrophic gastritis and intestinal metaplasia (52 of focal uplift type, 68 of verrucous uplift type and 48 of flocculence incrassation or depression type; 56 of type Ⅰ, 60 of type Ⅱ and 52 of type Ⅲ). A few expressions of Msi-1 were detected in the tissues of glandular neck or isthmus in patients with CNAG, and positive expression of Msi-1 was also detected in the tissues of patients with atrophic gastritis and intestinal metaplasia. The positive expression rates of Msi-1 in the tissues of patients with CNAG and with atrophic gastritis and intestinal metaplasia of focal uplift type, verrucous uplift type, flocculence incrassation or depression type were 25.0%(9/36), 69.2%(36/52), 76.5%(52/68) and 75.0%(36/48), respectively, with a significant difference among them (χ²= 31.850, P<0.05), and with significant differences between CNAG and with atrophic gastritis and intestinal metaplasia of  focal uplift type, verrucous uplift type, flocculence incrassation or depression type (χ²= 16.655, 25.714, 20.677, P<0.05). The positive expression rates of Msi-1 in the tissues of patients with type Ⅰ, type Ⅱ and type Ⅲ of intestinal metaplasia were 71.4%(40/56), 73.3%(44/60) and 76.9%(40/52), respectively, with no significant difference among them (χ²=0.432, P>0.05). There were no increased expressions of CDX2 in the tissues of patients with CNAG and obvious expressions of CDX2 in tissues of the gland of patients with atrophic gastritis and intestinal metaplasia. The positive expression rates of CDX2 in the tissues of patients with CNAG and with atrophic gastritis and intestinal metaplasia of focal uplift type, verrucous uplift type, flocculence incrassation or depression type were 13.9%(5/36), 80.8%(42/52), 82.4%(56/68)and 83.3%(40/48), respectively, with significant difference among them (χ²=65.973, P<0.05), and showing significant differences between focal uplift type, verrucous uplift type, flocculence incrassation or depression type of intestinal metaplasia and CNAG (χ²=38.289, 45.496, 39.886, P<0.05). The positive expression rates of CDX2 in the tissues with type Ⅰ, type Ⅱ and type Ⅲ of intestinal metaplasia were 89.3%(50/56), 80.0%(48/60) and 76.9%(40/52), respectively, with no significant difference among them (χ²=3.102, P>0.05). (3) Results of immunofluorescence double staining test: the specimens of 52 patients ［10 of CNAG and 42 of atrophic gastritis and intestinal metaplasia (13 of focal uplift type, 17 of verrucous uplift type and 12 of flocculence incrassation or depression type)］ were detected by immunofluorescence double staining. No double positive coexpression cell was detected in the tissues of patients with CNAG. There was a significant increase of double positive coexpression cells around goblet cells in the tissues of patients with atrophic gastritis and intestinal metaplasia. The coexpression rates of Msi-1 and CDX2 in the double positive cells of patients with focal uplift type, verrucous uplift type, flocculence incrassation or depression type were 41.4%±11.9%, 43.7%±12.7% and 42.8%±12.7%, respectively, with no significant difference among them (F=0.131, P>0.05). The positive coexpression rates of Msi-1 and CDX2 in the double positive cells of patients with type Ⅰ, type Ⅱ and type Ⅲ of intestinal metaplasia were respectively 33.8%± 10.6%, 43.8%±10.1% and 51.0%±2.7%, with significant differences among them (F=9.817, P< 0.05) and between type Ⅰ and type Ⅱ or type Ⅲ  (P<0.05), and with no significant difference between type Ⅱ and type Ⅲ  (P>0.05).
Conclusion:Expressions of Msi-1 and CDX2 are not related to the different 3 types of intestinal metaplasia, and coexpression of Msi-1 and CDX2 might be one of the important mechanisms during the transformation from intestinal metaplasia to gastric mucous neoplasms.