Transcriptome analysis reveals possible antitumor mechanism of Chlorella exopolysaccharide.

Microalgae, one of the most important classes of biomass producers, can produce exopolysaccharides similar to bacteria. The exopolysaccharide from Chlorella (CEPS) displays remarkable anticancer activity the mechanism of which remains to be elucidated. In this study, we analyzed the inhibitory effect of CEPS on the growth of HeLa cells. The results showed that CEPS inhibited the proliferation, decreased the viability, and changed the morphology of HeLa cells. Transcriptome analysis showed that 1894 genes were differentially expressed in the CEPS-treated group compared with the control group, including 1076 genes that were upregulated and 818 genes that were downregulated. The results of gene function enrichment analysis showed that the differentially expressed genes (DEGs) were significantly enriched in apoptosis and tumor-related biological processes and participated in several cancer and apoptosisrelated signaling pathways, including the MAPK signaling pathway, TNF signaling pathway, and the PI3K-Akt signaling pathway. The protein-protein interaction network identified 13 DEGs including PTPN11, RSAD2, ISG15, IFIT1, MX2, IFIT2, OASL, OAS1, JUN, OAS2, XAF1, ISG20, and IRF9 as hub genes. Our results suggest that CEPS is a promising therapeutic drug for the follow-up interventional therapy of cancer.

[Enhanced recovery after preserving the left colonic artery during laparoscopic anterior resection for rectal cancer].

OBJECTIVE: To evaluate the postoperative outcomes of preserving the left colonic artery during laparoscopic anterior resection for rectal cancer. METHODS: The clinicopathologic data of 91 rectal cancer patients (pathologic Stage II) undergoing laparoscopic anterior resection was retrospectively analyzed. During the surgeries, the left colonic artery was preserved in 40 patients (preserved group) and ligated in 51 patients (unpreserved group). The operating time, intraoperative blood loss, time to first flatus and defecation, duration of postoperative abdominal distension and pain, number of retrieved lymph nodes, ileum fistulation and anatomical leakage rate were compared between the two groups. RESULTS: The surgeries were completed in all the 91 patients laparoscopically without conversion. There was no intraoperative complications including rectal perforation, injury to vessel or ureter in either group. The operating time, blood loss and number of retrieved lymph nodes were similar between the groups (P>0.05). Three patients in preserved group and 5 in ligation group received preventive ileum fistulation due to low rectal cancer. Anatomical leakage occurred in three patients of unpreserved group. The average duration of postoperative abdominal distension and pain was 2.14∓0.35 days in preserved group and 3.15∓0.42 days in ligation group. The time to first flatus and defecation was 37.15∓12.62 h and 3.16∓0.52 days in preserved group and 62.25∓11.75 h and 4.25∓0.75 days in ligation group. Postoperative hospital stay was 4.54∓0.42 days in preserved group and 6.23∓0.51 days in ligation group. Total hospitalization cost in the two groups was 34 525.32∓1206.36 Yuan and 41 215∓1051.32 Yuan, respectively. Significant differences were found the in duration of postoperative abdominal distension and pain, postoperative hospital stay, and total cost between the two groups (P<0.05). CONCLUSION: During laparoscopic anterior resection for rectal cancer, preserving the left colonic artery effectively ensures the blood supply to the anastomosis and the remaining descending colon to promote the recovery of the patients after surgery.