Comparison of laparoscopy-assisted distal gastrectomy with open gastrectomy for advanced gastric cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility, safety and short-term outcomes of laparoscopy-assisted distal gastrectomy for advanced gastric cancer.</p><p><b>METHODS</b>From January 2007 to June 2008, 135 patients with advanced gastric cancer in the lower or middle stomach were operated, of whom 66 underwent laparoscopy-assisted distal gastrectomy(LADG) with D2 dissection of lymph nodes and 69 received conventional open D2 distal gastrectomy(ODG). Clinical data were recorded and compared between the two groups.</p><p><b>RESULTS</b>There were no significant differences in age, gender, and TNM staging between LADG and ODG(all P>0.05). All the patients in the LADG group underwent gastrectomy and lymph nodes dissection successfully without conversion to open surgery and no operative deaths occurred. The operative time was significantly longer for the LADG group than for the ODG group[(266.1±55.1) min vs. (223.8±26.8) min)]. The patients in the laparoscopic surgery group had less blood loss[(131.9±88.7) ml vs.(342.3±178.7) ml], earlier recovery of bowel activity[(3.18±1.22) d vs.(4.50±1.59) d], and shorter hospitalization time[(9.20±3.39) d vs. (11.35±4.61) d]. No significant differences were found in the total number of retrieved lymph nodes(25.81±12.53 vs. 27.47±10.28). The morbidity of complications was comparable between two groups(6.1% vs. 15.94%). No mortality and recurrence were observed during a follow-up period of 1-19 months.</p><p><b>CONCLUSIONS</b>LADG with D2 lymph node dissection is a safe and feasible procedure with adequate lymphadenectomy for advanced gastric cancer.</p>

Expression and its significance of retinoic acid receptor-beta in colorectal cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the expression and its significance of retinoic acid receptor-beta (RAR-beta) in colorectal cancer.</p><p><b>METHODS</b>RAR-beta was detected by immunohistochemistry methods and carcino-embryonic antigen (CEA) was tested by chemiluminescence immunoassay methods in normal tissues, paracancerous tissues and colorectal cancer tissues of 60 patients with colorectal cancer treated from January 2006 to January 2007. Above-mentioned data, together with the clinicopathological data of these 60 patients, were analyzed to figure out the expression and its significance of RAR-beta in colorectal cancer.</p><p><b>RESULTS</b>The expression rate of RAR-beta in tumor tissues (48%) was significantly lower than those in both normal tissues (87%) and paracancerous tissues (87%) (P < 0.05). And its expression was also significant lower in patients with lymph node metastasis (32%) and patients with advanced cancer (TNM stage III and IV) (29%) than in those without lymph nodes metastasis (60%) and those with early stage cancer (stage I and II) (69%). There was no significant differences among well, mildly and poorly differentiated cancer tissues. The CEA level rose in 20 patients, and its rising rate was remarkably higher in patients with lymph node metastasis (48%) and in patients with advanced cancer (52%) than those without lymph node metastasis (23%) and in early stage(14%).</p><p><b>CONCLUSIONS</b>The expression of RAR-beta decreases significantly in cancer tissues in patients with colorectal cancer, which may be related to the carcinogenesis of colorectal cancer; and its decreasing degree is correlated negatively with the lymph node metastasis and advanced clinicopathological stage. The expression level of RAR-beta may be a new prognostic indication of patients with colorectal cancer.</p>

Gene expression profile difference between colorectal cancer tissue and pericancerous mucosa by DNA microarray / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To study the difference of gene expression profile among colorectal cancer tissue, pericancerous mucosa and normal mucosa, and to screen associated novel genes in colorectal carcinogenesis by DNA microarray.</p><p><b>METHODS</b>cDNA chip containing approximate 8000 genes was used to detect differentially expressed genes in colorectal cancer tissues, pericancerous mucosa and normal mucosa, and to screen associated novel genes in colorectal carcinogenesis by DNA microarray.</p><p><b>RESULTS</b>As compared with normal mucosa, 769 genes differentially expressed in cancerous tissue were identified, which included 363 up-regulated and 406 down-regulated genes. In pericancerous mucosa 3 cm away from cancerous tissues, 155 genes differentially expressed were identified, of whom 52 genes were up-regulated and 103 were down-regulated. In pericancerous mucosa 5 cm away from cancerous tissues, 230 genes differentially expressed were identified, of whom 46 genes were up-regulated and 184 genes were down-regulated. The genes expressed differentially were associated with several functional types. According to the primary results, the differentially expressed genes with prominent functions included tumor-related genes, genes regulating cell proliferation and apoptosis, transcriptional control genes, and construction and degradation of extracellular matrix-associated genes. The cancerous mucosa was obviously different from the normal mucosa(about 20%, 769/3944). The differences between the normal mucosa and pericancerous mucosa were relatively small (3.9%,5.8%).</p><p><b>CONCLUSIONS</b>Different tissues have their own biological property. Several genes play roles in the development of colorectal carcinogenesis. Genes in adjacent non-cancerous tissues are also expressed differentially, leading to a malignant change.</p>

Effect of all-trans retinoic acid on drug sensitivity and expression of survivin in LoVo cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>All-trans retinoic acid (ATRA) can influence the tumor cell proliferation cycle, and some chemotherapeutic drugs are cycle specific. In this study, we hypothesize that ATRA can enhance chemotherapeutic drug sensitivity by affecting the cell cycle of tumor cells.</p><p><b>METHODS</b>The cell cycle of LoVo cells was evaluated using flow cytometry (FCM). Cell viability was analyzed using the MTT assay. The morphologic changes in the treated LoVo cells were measured with acridine orange (AO)/ethidium bromide (EB) staining. Expression of survivin in LoVo cells was analyzed by immunofluorescence assay.</p><p><b>RESULTS</b>After LoVo cells were treated with ATRA, the G0/G1 ratio of the tumor cells increased and the cell ratio of S- and G2/M-phase decreased. Viability of the cells decreased significantly after combined treatment with ATRA and 5-fluorouracil (5-FU) or mitomycin c (MMC) and was evaluated by fluorescence microscopy. Expression level of survivin in the tumor cells decreased after ATRA combination treatment.</p><p><b>CONCLUSIONS</b>ATRA enhances drug sensitivity of the LoVo cell line to cell cycle-specific agents and inhibits the expression of survivin in LoVo cells. The combination of ATRA and 5-FU or MMC promoted cell apoptosis, and the mechanism involved in apoptosis may be related to inhibition of survivin gene expression.</p>