Bo Feng

Normal and modified urinary nucleosides represent novel biomarkers for colorectal cancer diagnosis and surgery monitoring

Background: Up to now, there is still no ideal tumor marker in early diagnosis and effective monitoring, especially for surgical resection of colorectal cancer (CRC). The aim of the present study was to evaluate the application of urinary normal and modified nucleosides in diagnosis and surgery monitoring of CRC.

Clinical advantages of laparoscopic colorectal cancer surgery in the elderly.

Background and aims: Elderly patients have a high incidence of colorectal cancer, which may be associated with increased morbidity and mortality due to complex comorbidity and diminished cardiopulmonary reserves. The aims of this study were to compare the outcomes of laparoscopic colorectal cancer surgery with those observed in traditional open surgery in patients aged over 70 years. Methods: Between January 2003 and October 2004, 51 patients aged over 70 years with colorectal cancer, who underwent laparoscopic surgery (LAP group), were evaluated and compared with 102 controls (also over 70 years old) treated by traditional open surgery (OPEN group) in the same period. All patients were evaluated with respect to the American Society of Anesthesiologists (ASA) classification, surgery-related complications, and postoperative recovery. Results: No surgery-related death was observed in the LAP group, whereas two deaths occurred in the OPEN group for severe post-operative pulmonary infection and anastomotic leak, respectively. No pneumoperitoneum-related complications were observed in the LAP group; 2 (3.9%) patients required conversion to open surgery, because of the unexpectedly bulky tumor and severe adhesions in the abdominal cavity. With the increase in patients’ age, increased ASA classification was observed. No significant differences were observed in gender, Dukes’ staging or types of procedures between LAP and OPEN groups. The overall morbidity in the LAP group was significantly less than that of the OPEN group [17.6% (9/51) vs 37.3% (38/102), p=0.013]. Mean blood loss, time to flatus passage, and time to semi-liquid diet in the LAP group were significantly shorter than those of the OPEN group (90.7±49.9 vs 150.3±108.7ml, 2.4±1.2 vs 3.5±2.9 d, 5.0±1.8 vs 5.9±1.2 d, respectively, p<0.05). No significant differences were observed in terms of mean operation time or hospital stay between LAP and OPEN groups. Conclusion: Laparoscopic colorectal cancer surgery in elderly patients with colon cancer has clinically significant advantages over traditional open surgery, and appears to be the ideal surgical choice for the elderly.

Clinical significance of human kallikrein 10 gene expression in colorectal cancer and gastric cancer

Background and Aim:u2002 Recent evidence suggests that the human kallikrein 10 (KLK10) gene is differentially regulated in endocrine‐related tumors and has potential as diagnostic and/or prognostic marker; however, KLK10 expression has never been investigated in gastrointestinal cancers. The aims of this study were to demonstrate expression and single nucleotide polymorphisms of KLK10 in colorectal cancer (CRC) and gastric cancer (GC), and to correlate the relative KLK10 expression level with clinicopathological factors of CRC and GC.

Polo-like kinase 1 is overexpressed in colorectal cancer and participates in the migration and invasion of colorectal cancer cells.

Summary Background Polo-like kinase 1 (PLK1) is an important molecule in proliferation of many human cancers. The aim of study is to clarify the expression patterns and potential function of PLK1 in colorectal cancers. Material/Methods Fifty-six colorectal cancers samples were collected and arranged onto a tissue array and the expression of PLK1 were detected by immunohistochemistry and correlated with clinico-pathological characteristics and expression of PCNA. Expression of PLK1 in 9 colorectal cancer cells lines was investigated by RT-PCR and Western blot, then SW1116 cells lines were treated with PLK1 siRNA and the efficiency was examined by Western blot. Transwell test was applied to detect the migration and invasion capability of cancer cells by counting the number of cells passing through the membranes. Cell proliferation and apoptosis were examined by Cell Counting Kit-8 (CCK-8) and Annexin-V Kit. Results PLK1 was positively expressed in 73.2% (41/56) of colorectal cancers tissues, but in only 3.6% (2/56) of normal tissues, and was associated with Duke’s stage (P<0.01), tumor size (P<0.01), invasion extent (P<0.05) and lymphatic metastasis (P<0.01). The expression of PLK1 was correlated with expression of PCNA (R=0.553, P<0.01). PLK1 was inhibited in SW1116 cells by treating with PLK1 siRNA oligos, which resulted in a decreased number of cells passing through the membrane as compared with control groups (P<0.01) at 24 hours after transfection. Cell proliferation was inhibited from 48 hours after transfection, while cells apoptosis was induced from 72 hours after transfection. Conclusions PLK1 could be a progression marker for colorectal cancer patients and PLK1 depletion can inhibit migration and invasion capability of colorectal cancer cells SW1116, suggesting that PLK1 might be involved in metastasis and invasion of colorectal cancer. Therapeutic strategies targeting PLK1 may be a new approach to colorectal cancer.

A study evaluating the safety of laparoscopic radical operation for colorectal cancer

Aim: This study aimed to assess the safety and feasibility of laparoscopic curative resection for colorectal cancer through the clinical practice and basic research. Material and Methods: From September 2001 to September 2002, 47 patients with colorectal cancer were treated using laparoscopic approach, compared with 113 patients underwent traditional operation. The length of intestinal segment excised, size of tumour, clearance of lymph nodes, local recurrence and distant metastasis rate during the period of follow-up in both groups were compared. The other part of the study involved the detection of exfoliated tumour cells in the peritoneal washing before and after surgery; flushing of the instruments was performed in both groups and the results compared. For the laparoscopic cases, the filtrated liquid of CO2 pneumoperitoneum was also checked for tumour cells. Results: No significant differences existed in tumour size, operative site and manner between the two groups. The exfoliated tumour cell was not detected in the CO2 filtrated liquid. Between both groups there was no difference in the incidence of exfoliated tumour cells in peritoneal washing before and after surgery as well as in the fluid used for flushing the instruments. The total number of lymph nodes harvested was 13.71±9.57 for the laparoscopic group and 12.10±9.74 for the traditional procedure. Similar length of colon was excised in both groups; this was (19.38±7.47) cm in the laparoscopic and (18.60±8.40) cm in the traditional groups. The distal margins of resection for rectal cancer were (4.19±2.52) cm and (4.16±2.00) cm respectively. The local recurrence rate was 2.13% (1/47) and 1.77% (2/113) with the distant metastasis rate 6.38% (3/47) and 6.19% (7/113) respectively. Both the statistics were comparable between the laparoscopic and traditional surgery for the colorectal cancer. Conclusion: Laparoscopic curative resection for colorectal cancer can be performed safely and effectively. In the treatment of colorectal malignancy, laparoscopic resection can achieve similar radicalilty as compared to the traditional laparotomy.