OBJECTIVETo explore the expression of KIF18A gene protein in gastric cancer tissues and its association with the prognosis of patients.

METHODSTwenty fresh paired gastric cancer specimens and adjacent normal mucosa(at least 5 cm from the edge of tumor) from 20 gastric cancer patients undergoing operation in Department of General Surgery at the First Affiliated Hosptial of Anhui Medical University between March 2015 and July 2015 were collected. Real-time PCR was used to examine KIF18A mRNA expression in above specimens. Meanwhile, paraffin embedded cancer tissue samples from 129 gastric cancer patients undergoing operation and 23 samples of randomly selected normal gastric tissue(adjacent non-cancer tissue) were collected to establish the microarray. Immunohistochemistry method was applied to detect the KIF18A protein expression in the microarray after confirmation by pathologists. Association of KIF18A expression with clinicopathological features in gastric cancer patients was evaluated. Cox proportional hazard model was used to identify prognostic risk factors.

RESULTSAmong 20 fresh paired gastric cancer specimens, mRNA expression of KIF18A in 16 specimens was obviously lower than that in adjacent normal tissues. The positive rate of KIF18A protein expression in gastric cancer tissues was significantly lower than that in normal gastric tissues in microarray[45.0%(58/129) vs. 69.6%(16/23), P=0.041]. KIF18A protein expression was significantly associated with invasion depth (P=0.008) and TNM staging (P=0.032). The median overall survival of all the 129 patients was 44.0(95% CI: 39.78-49.24) months. The three-year survival rates of patients with high and low KIF18A expression were 67.2% and 36.6% respectively(P=0.020). Cox regression analysis showed that KIF18A expression was an independent protective factor of the prognosis of gastric cancer patients (HR=0.570, 95% CI:0.335 to 0.970).

CONCLUSIONSKIF18A expression is down-regulated in gastric cancer tissue, which may play a critical role in gastric cancer carcinogenesis. Lower expression of KIF18A is associated with poor prognosis of gastric cancer patients. KIF18A may be a potential prognostic marker of gastric cancer.

Biomarkers, Tumor ; metabolism ; Humans ; Immunohistochemistry ; Kinesin ; metabolism ; Neoplasm Staging ; Prognosis ; Proportional Hazards Models ; Real-Time Polymerase Chain Reaction ; Regression Analysis ; Stomach Neoplasms ; diagnosis ; metabolism ; Survival Rate

Objective:To investigate the expression of Piezo1 in small intestinal mucosal epithelial cells of patients with Crohn′s disease (CD) and its clinical correlation with CD.Methods:From January 1st 2010 to November 30th 2020, the clinical data including age, gender, disease location and biological behavior, etc of 57 patients with CD (CD group) who underwent surgery at The First Affiliated Hospital of Anhui Medical University were retrospectively. And at same time the normal samll intestinal epithelial tissues of 10 healthy individuals who underwent colonoscopy were collected as the healthy control group. The expression of Piezo1 in small intestinal epithelial cells of CD patients with different disease sites, biological behavior and disease activity were detected by immunofluorescence staining and hematoxylin-eosin staining. The histological score system and intestinal fibrosis score were used to analyze the inflammation and fibrosis of the intestinal tissues of patients with CD. Semi-quantitative analysis of Piezo1 in small intestinal epithelial cells was analyzed by ImageJ software. And the correlation between Piezo1 expression and clinical characteristics and pathological features of small intestine was also analyzed. Independent sample t test and analysis of variance were used for statistical analysis. Results:In CD group, there were 37 males (64.9%) and 20 females (35.1%). The age was (39.1±14.2) years old, ranged from 18 to 71 years old, and the average duration of the disease was (26.5±24.1) months. There were 29 cases (50.9%)of ileal type, 26 cases (45.6%) of ileocolonin type and 2 cases (3.5%) of colonic type. There were 12 cases (21.1%) of non-penetrating non-stenotic type, 31 cases (54.4%) of stenotic type and 14 cases (24.6%) of penetrating type. There were 47 cases (82.5%) with moderate activity and 10 cases (17.5%) with severe activity. There were 17 cases (29.8%) of moderate intestinal inflammation, 40 cases (70.2%) of severe intestinal inflammation. The score of intestinal fibrosis in six cases (10.5%) was 1, 28 cases (49.1%) was 2, 18 cases (31.6%) was 3, five cases was 4. The relative expression level of Piezo1 in intestinal mucosal epithelial cells of CD group was higher than that of healthy control group (12.9±4.6 vs. 8.5±1.1), the relative expression of Piezo1 in intestinal mucosal epithelia cells of stenotic type and penetrating type CD patients were both higher than that of non-penetrating and non-stenotic CD patients (12.6±3.8 and 9.8±2.4 vs. 6.0±1.3), and the differences were all statistically significant ( t=3.00, -3.66 and -3.32, all P<0.01). The relative expression of Piezo1 in small intestinal epithelial cells of CD patients with severe intestinal inflammation was higher than that of CD patients with moderate intestinal inflammation (13.1±4.0 vs. 9.7±3.1), and the difference was statistically significant ( t=-2.65, P<0.05). The relative expression levels of Piezo1 in small intestinal epithelial cells of patients with intestinal fibrosis score of 4, 3, 2 and 1 were 17.6±5.2, 12.6±1.7, 9.1±2.1 and 5.8±1.1, respectively; the relative expression levels of Piezo1 in intestinal epithelial cells of patients scored 4 were higher than that of patients scored 3, 2 and 1, and that of patients scored 3 was higher than patients scored 2 and 1, and that of patients scored 2 was higher than that of patients scored 1, and the differences were all statistically significant ( t=-2.98, -5.10, -3.84, 4.60, 6.55 and 2.56, all P<0.05). The relative expression of Piezo1 in intestinal mucosal epithelial cells was related to the severity of intestinal inflammation and fibrosis. The more severe the intestinal inflammation and fibrosis, the higher the relative expression of Piezo1 in intestinal mucosal epithelial cells. Conclusions:The relative expression of Piezo1 in small intestinal epithelial cells is related to the biological behavior and the severity of intestinal inflammation and fibrosis of CD. It is speculated that the expression of Piezo1 in small intestinal epithelial cells may be clinically related to the process of intestinal wall fibrosis in CD to some extent, however whether it plays an important role in the process of intestinal wall fibrosis in CD and its specific mechanism need to be further studied.