Study of the effect of LIG4 on the radiosensitivity enhancement of rectal cancer cells by curcumin / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the function of repair gene LIG4 in radiosensitivity enhancement of rectal cancer cells by curcumin.</p><p><b>METHODS</b>Human rectal cancer cells HT-29 were cultured in normal. LIG4-overexpression HT-29 cells and blank control plasmid HT-29 cells were established by gene transfection. Both kind of HF-29 cells were further randomly divided into curcumin group, radiotherapy group, curcumin plus radiotherapy group (combined group) and control group. The growth inhibition and apoptosis of cells were detected by MTT and Annexin V/PI respectively. Change of tumor volume was observed in nude mouse xenograft model, and the apoptosis of tumor cells was analyzed by TUNEL.</p><p><b>RESULTS</b>Regarding blank control plasmid HT-29 cells, the growth inhibition rate and apoptosis rate in combined group were significantly higher than those in radiotherapy group(all P<0.05); tumor volume of nude mouse in combined group was significantly smaller than that in radiotherapy group, and the apoptotic index in combined group was significantly higher than that in radiotherapy group (all P<0.05). However, regarding LIG4-overexpression HT-29 cells, the growth inhibition rate and apoptosis rate were not significantly different between combined group and radiotherapy group(all P>0.05); the tumor volume of nude mouse and the apoptotic index were also not significantly different between combined group and radiotherapy group (all P>0.05).</p><p><b>CONCLUSION</b>Down-regulation of LIG4 is an important mechanism of radiosensitivity enhancement of rectal cancer cells by curcumin.</p>

Mechanism of radiotherapy sensitization of curcumin on rectal cancer cells / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To elucidate the mechanism of curcumin in radiotherapy sensitization for colorectal cancer cells.</p><p><b>METHODS</b>Colorectal cancer HT-29 cells were cultured and treated with radiation and curcumin. MTT method was used to detect the cell growth inhibition. Then the high-throughput microarray was used to detect the differences in gene expression levels for each test group to identify differentially expressed genes, and each differential gene was validated by Western blotting.</p><p><b>RESULTS</b>Cell growth inhibition rates at 48-hour and 72-hour in curcumin combined with radiotherapy group were significantly higher than those in simple radiotherapy group (P<0.05). Expression of 95 genes associated with gene-injury repair was detected by microarray. Compared to simple radiotherapy group, LIG4 and PNKP expression was down-regulated, and XRCC5 and CCNH expression was up-regulated in the curcumin combined with radiotherapy group (all P<0.05). Western blotting revealed LIG4 and PNKP protein expression decreased, and XRCC5 and CCNH protein expression increased in the curcumin combined with radiotherapy group as compared to the simple radiotherapy group (all P<0.05).</p><p><b>CONCLUSION</b>Radiation sensitization effect of curcumin on colorectal cancer cells HT-29 may be associated with the regulation of genes of CCNH, LIG4, XRCC5, PNKP.</p>

Modified ligation of the intersphincteric fistula tract in the treatment of simple transsphincteric perianal fistula / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To assess the efficacy and safety of modified ligation of the intersphincteric fistula tract for simple transsphincteric perianal fistula.</p><p><b>METHODS</b>Seventy patients with simple transsphincteric perianal fistula between October 2012 and January 2014 in our department were prospectively enrolled. According to the random number table, patients were divided into two groups: modified-LIFT group (37 cases, from the external opening close to the fistula, dissect the external sphincter fistula to the intersphincteric groove by tunneling technique, resect the lateral free fistula) and LIFT group (33 cases). Clinical parametres before and after operation were compared, and results of pelvic electromyogram (EMG) and anorectal manometry three months after operation were analyzed to evaluated anal function.</p><p><b>RESULTS</b>The operative time, pain score, hospital stay, and healing time were not significantly different between the two groups (all P>0.05). During the median follow-up of 12 months (3-20 months), the healing rate in modified-LIFT group was 83.8% (31/37), which was significantly higher than 60% (20/33) in LIFT group (P=0.029). After operation, 4 patients had persistent unhealed wound, 2 recurred in modified-LIFT group, while 8 patients had persistent unhealed wound, and 5 recurred in LIFT group. No patients developed anal incontinence. By the pelvic EMG and anorectal manometry 3 months after operation, the duration of motor unit potential, occurrence of simple phase, mean resting pressure and maximun squeeze pressure were not significantly different.</p><p><b>CONCLUSION</b>Modified-LIFT procedure for the management of simple transsphincteric perianal fistulas is a simple and effective operation with higher healing rate and similar anal function as LIFT.</p>

Evaluation of anal function and quality of life after transanal endoscopic microsurgery / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the impact of transanal endoscopic microsurgery (TEM) on postoperative anal function and quality of life in patients with benign rectal tumor and early rectal cancer.</p><p><b>METHODS</b>Clinical data of 50 patients with rectal adenoma and early rectal cancer undergoing transanal endoscopic microsurgery in our hospital from October 2008 to June 2013 were retrospectively analyzed. Anorectal manometry, endorectal ultrasonography (ERUS), the fecal incontinence severity index (FISI), and the physical and mental health status scores (SF-36) were used to evaluate preoperative and postoperative anorectal function and quality of life.</p><p><b>RESULTS</b>Anorectal manometry indicated anal resting pressure (ARP), maximum squeeze pressure (MSP), rectal volume at sensory threshold(RVST), maximum tolerable volume(MTV) decreased significantly at the first month after surgery (P<0.05). MSP returned to preoperative level at the 3rd month (P>0.05). ARP and MTV returned to normal values at the 6th month (P>0.05). RVST returned to normal values at the 9th month (P>0.05). Recto-anal inhibitory reflex(RAIR) was absent in 1 (2%) patient preoperatively and in 30(60%), 18(36%), 7(14%), 2(4%) at the 1st, 3rd, 6th, 9th months after surgery respectively. ERUS showed similar width and thickness of internal sphincter at 1st and 6th month after surgery compared with preoperative measures (P>0.05). Six months after surgery, the mean FISI score decreased(preoperative vs postoperative:8.5 vs 5.8, P<0.05), suggesting an improvement in fecal continence. However, the overall quality of life did not danger significantly after surgery(P>0.05).</p><p><b>CONCLUSIONS</b>TEM has little impact on anorectal anatomic structure. Anal function may be compromised in the short-term, however the vast majority of patients recover completely after 6-9 months. TEM is a safe, effective and minimally invasive surgery.</p>