肠息肉发生的细胞和分子生物学研究进展

Colonoscopic electrosurgical resection of high-risk polyps: Pretreatment methods

AIM: To discuss the pretreatment techniques and methods for colonoscopic electrosurgical resection of high-risk polyps.

METHODS: This study comprised 131 patients, who had a total of 145 high-risk colorectal polyps, including wide-pedicle polyps, large polyps, and those with a hyperemic surface, obvious blood vessels through the base, or poor endoscopic exposure). For wide-pedicle polyps (pedicle diameter > 1 cm), nylon snare ligation was performed before electrosurgical resection. For large pedunculated polyps (>2 cm, pedicle diameter < 1 cm), titanium clipping was performed before electrosurgical resection. For 2.0-3.0 cm wide-base/Artie polyps, fully lifting of polyps was achieved by basal submucosal injection of liquid before the resection of polyps. For polyps with a hyperemic surface, obvious blood vessels through the base, or poor endoscopic exposure, trial colonoscopic resection was initially performed. If the resection was difficult, immediate laparoscopic treatment was given. Intestinal bleeding, intestinal perforation and other complications were recorded.

RESULTS: Nylon snare ligation was performed in 10 polyps, metal titanium clamping in 32 polyps, basal submucosal injection in 60 polyps, colonoscopic resection in 31 polyps, and laparoscopic resection in 12 polyps. No intestinal bleeding, intestinal perforation or other severe complications occurred.

CONCLUSION: Effective pretreatment can improve the management of high-risk intestinal polyps, and endoscopic treatment can improve the safety of treatment and avoid the occurrence of intestinal bleeding, intestinal perforation and other complications.

Significance of expression of E-cadherin and β-catenin in juvenile colorectal polyps in children

AIM: To detect the expression of E-cadherin and β-catenin mRNAs and proteins in human colorectal juvenile polyps (JP) in children.

METHODS: The expression of E-cadherin and β-catenin mRNAs and proteins in 22 juvenile colorectal polyp specimens and 8 normal colorectal specimens was assayed by real-time PCR and Western blot, respectively. Immunohistochemistry was used to determine the expression and localization of E-cadherin and β-catenin in 30 juvenile colorectal polyp specimens and 10 normal colorectal specimens.

RESULTS: Real-time PCR and Western blot analyses showed that the expression levels of E-cadherin mRNA and protein were significantly lower in juvenile colorectal polyps than in normal colorectal specimens (1.1526 ± 0.3801 vs 0.4094 ± 0.2305, P < 0.05; 0.6028 ± 0.1778 vs 0.3257 ± 0.1168, P < 0.05). Although there was no significant difference in the expression level of β-catenin mRNA between the two groups, the expression of β-catenin was significantly higher in juvenile colorectal polyps than in normal colorectal specimens (0.8010 ± 0.1380 vs 1.2064 ± 0.3587, P < 0.05). Immunohistochemistry indicates that E-cadherin expression was down-regulated in juvenile polyps compared with controls (102.5155 ± 25.2988 vs 53.5772 ± 15.3205, P < 0.05). Positive staining for E-cadherin was predominantly localized on the epithelial cell membrane. The expression of β-catenin was increased in juvenile polyp specimens (112.0805 ± 24 9572 vs 260.3554 ± 86.6987, P < 0.05), and the positive rates of membrane, cytoplasmic and nuclear staining in juvenile polyp tissue was significantly higher than those in normal control tissues.

CONCLUSION: Dysregulation of E-cadherin and β-catenin expression may be an important feature of juvenile colorectal polyps.