CSRP1 Promotes Colon Adenocarcinoma Growth and Serves as an Independent Risk Biomarker for Worse Prognosis.

Background: Cysteine and Glycine Rich Protein 1 (CSRP1) belongs to the cysteine-rich protein family, which contains a unique double-zinc finger motif and is important for development and cellular differentiation. Abnormal expression of CSRP1 was reported within several malignancies such as prostate cancer and acute myeloid leukemia. Here, we explored function of CSRP1 within colon adenocarcinoma (COAD) for the first time. Methods: The mRNA levels of CSRP1 in COADs were obtained from TCGA datasets. CSRP1 protein expressions in COADs were tested via immunohistochemistry staining. Patients' prognosis was evaluated using both univariate analysis and multivariate analysis. Two human COAD originated cancer cell lines, Caco-2, and HT-29, were used for cellular experiments including shRNA knockdown, proliferation assay, and migration assay. In vivo model was established using nude mice xenografts to further validate the role of CSRP1 in COAD progression. Results: The mRNA levels of CSRP1 are elevated in COAD specimens from patients with more advanced tumor stages and higher Carcinoembryonic Antigen (CEA) levels. In addition, higher CSRP1 mRNA level indicates worse COAD prognosis. Consistently, higher CSRP1 protein expression is correlated with worse overall survival according to both univariate and multivariate analysis, indicating that CSRP1 is a new COAD prognostic factor. Furthermore, COAD cells transfected with CSRP1-shRNAs exhibit attenuated proliferation and migration capacities. Finally, growth of xenografts originated from CSRP1-knockdown cells is inhibited comparing to the control ones. Conclusions: Expression of CSRP1 is positively correlated with COAD progression, which can promote tumor growth and migration. Higher CSRP1 can is a novel independent prognostic factor of COAD.

Three-Port with Natural Orifice Specimen Extraction versus Conventional Laparoscopic Anterior Resection for Rectal-Sigmoid Cancer: A Matched Pair Analysis.

BACKGROUND: The conventional laparoscopic colorectal surgery requires four or more ports to accomplish the laparoscopic dissection, and a mini-laparotomy to remove the specimen, which is a main cause of postoperative pain and incision complications, and compromise the cosmetic results. Reduced port surgery and natural orifice specimen extraction (NOSE) surgery hold the promise to overcome these drawbacks. This study planned to compare peri-operative outcomes of patients with rectal-sigmoid cancer undergoing three-port laparoscopic anterior resection with NOSE (three-port NOSE LAR) to those of patients receiving conventional LAR. METHODS: Twenty-five patients with rectal-sigmoid cancer underwent three-port NOSE LAR between December 2018 and October 2020. For comparison, 50 patients with rectal-sigmoid cancer underwent conventional LAR in the same period were matched. The peri-operative outcomes were compared. RESULTS: Operating time of three-port NOSE group was slightly longer than that of conventional group (135 min vs. 121 min, p = .147). The incision length of three-port NOSE group was shorter than that of conventional group (2.9 cm vs. 7.4 cm, p = .000). Complication rates in three-port NOSE group and conventional group were similar (12.0% vs. 20.0%, p = .524). The tumor size was smaller in three-port NOSE group than the conventional group (2.1 cm vs. 3.5 cm, p = .000). Pain score was lower in three-port NOSE group than the conventional group at postoperative day 1 (1.6 vs. 3.0, p = 0.045) and day 2 (0.2 vs. 2.1, p = .003). The BIQ score was significantly higher in the three-port NOSE group compared to the conventional group (42.9 ± 3.5 vs. 38.2 ± 2.5, p = .002). CONCLUSIONS: Three-port NOSE LAR for rectal-sigmoid cancer is feasible and provides similar peri-operative outcomes compared to conventional LAR. It reduces postoperative pain and produces better cosmesis.

Laparoscopic-Assisted Modified Intersphincter Resection for Ultralow Rectal Cancer.

BACKGROUND: Intersphincter resection (ISR) is considered to be a superior technique offering sphincter preservation in patients with ultralow rectal cancer.1 Because high-definition laparoscopy offers wider and clearer vision into the narrow pelvic cavity and intersphincteric space, ISR has been further refined.2 However, functional outcome after ISR has not been optimal. More than half of patients receiving ISR suffer partial or even complete anal incontinence.3 We therefore propose a laparoscopic-assisted modified ISR, with the aim of improving sphincter function following ISR. METHODS: The video describes the technique for performing such laparoscopic-assisted modified ISR in a 62-year-old woman with ultralow rectal cancer (3 cm from anal verge). Preoperative staging by endorectal ultrasound and pelvic magnetic resonance imaging revealed stage I rectal cancer (cT2N0M0). The operation consisted of an abdominal and a perineal phase. The abdominal phase routinely involved colonic mobilization with high ligation of inferior mesenteric vessels, total mesorectal excision (TME), as well as transabdominal intersphincteric dissection. The procedure for laparoscopic TME was performed according to our published method.4 Along the TME dissection plane, the puborectalis could be reached and the intersphincteric space was entered posterolaterally. The hiatal ligament at the posterior side of the rectum was transected afterwards. The dissection of the intersphincteric space was continued caudally at the anterior side of the rectum. The distal bowel wall was mobilized for 2 cm from the lower edge of the tumor to obtain adequate distal margin. At this point, circular dissection of the intersphincteric space was completed. After the abdominal phase, perineal dissection was performed with wide exposure by use of a hooked self-retaining retractor. The lower margin of the tumor was identified under direct vision. We developed a modified ISR technique. Resection of the mucosa and internal sphincter was initiated 2 cm distal to the lower edge of the tumor at the tumor side to obtain the necessary distal margin. Meanwhile, at the opposite side of the tumor, the resection line was just above the dentate line so that partial dentate line could be preserved. After removal of the specimen en bloc per anus, the pelvic cavity was generously irrigated with diluted povidone iodine solutions. The distal margin of the specimen was then examined by frozen section for presence of cancer. If clear, coloanal anastomosis was performed using a handsewn technique. The colon was rotated 90° and anastomosed to the anal canal with interrupted absorbable 3-0 sutures. Finally, a pelvic suction drain was placed, and a temporary diverting stoma made in the terminal ileum. RESULTS: There were no intraoperative complications. The operating time was 180 min. Blood loss was 50 mL. The distal margin was clear, and the final pathology was pT2N0M0. The patient underwent an uneventful recovery. She began sphincter-strengthening exercises 2 weeks after surgery. The stoma was closed after examinations 3 months later. No local recurrence or distant metastasis was found. At 12-month follow-up, in terms of sphincteric function, the patient was continent to solids, liquids, and flatus. CONCLUSIONS: Laparoscopic-assisted modified intersphincter resection for ultralow rectal cancer is safe and feasible. This technique should be considered whenever possible as a means to offer sphincter preservation and improve sphincter function in patients with ultralow rectal cancer.

Age-specific impact on the survival of gastric cancer patients with distant metastasis: an analysis of SEER database.

The age-specific impact on the survival of gastric cancer patients with distant metastasis is still unclear. In this study, we identified 11, 299 gastric cancer patients with distant metastasis between 2004 and 2013 from Surveillance, Epidemiology, and End Results population-based dataset. Patients were divided into young (≤60) and elderly groups (>60). Kaplan-Meier methods and multivariable Cox regression were used for the analysis of long-term survival outcomes and risk factors. There were significant differences between the two groups in terms of race, primary site, grade, histologic type, surgery, marital status and clinical T stage (P<0.05). The 1- and 3-year cancer specific survival rates were 29.0% and 6.2% in young group and 22.8% and 4.8% in elderly group in both univariate (X2=116.430, P<0.001) and multivariate analysis (P<0.001). Young patients had significantly better 1- and 3-year cancer specific survival than elderly patients in each T stage. Age was further validated as an independent survival factor in all T stages (T1, T2, T3, T4 and TX, P<0.05). In conclusion, age was an independent prognostic factor for gastric cancer patients with distant metastasis.

The influence of marital status on survival of gallbladder cancer patients: a population-based study.

Marital status has been found to be a prognostic factor for survival in various cancers, but its role in gallbladder cancer (GBC) has not been fully studied. In this study, we used the Surveillance, Epidemiology, and End Results Program (SEER)-registered database to analyze the survival of GBC patients with different marital status. A total of 6,627 GBC patients were selected from SEER database from 2004 to 2013. The age, race, grade, histologic type, AJCC stage, SEER stage and marital status were identified as independent prognostic factors. Married GBC patients had a higher 5-year cancer-specific survival (CSS) than that of unmarried ones (20.1% v.s. 17.8%, P < 0.05). Subgroup analyses showed that widowed patients had 14.0% less of 5-year CSS compared to married ones of stage I (55.9% v.s. 41.9%, P < 0.05), 14.7% of stage II (15.6% v.s. 10.9%, P < 0.05), and 1.5% of stage III + IV (2.9% v.s. 1.4%, P < 0.05). In addition, single is an independent prognostic factor at stage III + IV (HR = 1.225, 95%CI 1.054-1.423, P = 0.008). These results indicated that widowed patients were at a high risk of cancer-specific mortality and marriage can be a protective prognostic factor in CSS.

Systematic review and meta-analysis of somatostatin analogues in the prevention of postoperative complication after pancreaticoduodenectomy.

BACKGROUND: The use of somatostatin analogues (SAs) following pancreaticoduodenectomy (PD) is controversial. METHOD: Literature databases were searched systematically for relevant articles. A meta-analysis of all randomized controlled trials (RCTs) evaluating prophylactic SAs in PD was performed. RESULTS: Fifteen RCTs involving 1,352 patients were included. There was a towards reduced incidences of pancreatic fistulas (p = 0.26), clinically significant pancreatic fistulas (p = 0.08), and bleeding (p = 0.05) in prophylactic SAs group. In subgroup analyses, prophylactic somatostatin significantly reduced the incidence of pancreatic fistulas(p = 0.02), with a nonsignificant trend toward reduced incidence of clinically significantly pancreatic fistulas (p = 0.06).Pasireotide significantly reduced the incidence of clinically significantly pancreatic fistulas (p = 0.03). Octreotide had no influence on the incidence of pancreatic fistulas. CONCLUSION: The current best evidence suggests prophylactic treatment with somatostatin or pasireotide has a potential role in reducing the incidence of pancreatic fistulas, while octreotide had no influence on the incidence of pancreatic fistulas.High-quality RCTs assessing the role of somatostatin and pasireotide are required for further verification.

A simple, secure and universal two-layer continuous running suture pancreaticojejunostomy following pancreaticoduodenectomy.

Pancreatic fistula is a leading cause of morbidity and mortality after pancreaticoduodenectomy. We introduce here a simple, secure and universal technique for pancreaticojejunostomy with a two-layer continuous running suture. We also report on the preliminary results for grades of pancreatic fistulas among patients who underwent this new technique. 51 consecutive cases were successfully performed using this new technique during pancreaticoduodenectomy. The overall morbidity was 29.4%. Only 3 (5.9%) grade B pancreatic fistulas were observed postoperatively, and were successfully treated with conservative management. The time taken to create the pancreatic anastomosis was less than 15 minutes in all cases. In conclusion, this novel pancreatic anastomosis technique is easy and quick to perform, universally applicable, and appears to be a secure technique that reduces pancreatic fistula rates after pancreaticoduodenectomy.

Preoperative oral carbohydrate improved postoperative insulin resistance in rats through the PI3K/AKT/mTOR pathway.

BACKGROUND: Preoperative oral carbohydrate (OCH) improves postoperative insulin resistance (PIR) and insulin sensitivity. However, the exact mechanisms involved in the improvement of PIR with respect to preoperative OCH are still not clear. The aim of this study was to investigate the involvement of preoperative OCH and PI3K/AKT/mTOR pathway in reducing PIR in rats. MATERIAL AND METHODS: Forty male Sprague-Dawley rats were randomly assigned to PreOp, glucose, saline, and fasting groups. Rats in the PreOp, glucose, and saline groups received OCH, 5% glucose solution, and saline, respectively. Rats in the fasting group did not receive anything but were fasted 3 h before surgery. Blood glucose, insulin and leucine levels, and insulin resistance, secretion, and sensitivity indexes were measured before and after surgery. mRNA and protein (total and phosphorylated) levels of mTOR, IRS-1, PI3K, PKB/AKT, and GlUT4 were measured using real-time polymerase chain reaction and Western blot in skeletal muscles. RESULTS: In the PIR experiment, blood glucose, serum insulin, insulin resistance, and serum leucine levels were all significantly lower in the PreOp group than in the other 3 groups (P<0.05) after surgery. HOMA-ISI were higher in the PreOp group vs the other 3 groups after surgery (P<0.05), and HOMA-b in the PreOp group was higher than that in the other 3 groups at 30 and 120 min after surgery. Additionally, post-operative phosphorylated IRS-1, PI3K, and AKT protein levels were significantly higher in the PreOp group than in the other 3 groups (P<0.05), but no significant differences were observed in their respective protein levels (P>0.05). CONCLUSIONS: OCH decreases postoperative insulin resistance and improves postoperative insulin sensitivity in skeletal muscles through the PI3K/AKT/mTOR pathway.

Nerve-guided laparoscopic total mesorectal excision for distal rectal cancer.

BACKGROUND: Urogenital dysfunctions are well-recognized problems after rectal cancer surgery and are often due to autonomic nerve damage. Although following holy planes during total mesorectal excision (TME) reduces the possibility of damage to the autonomic nerve fibers, these could still be affected in some critical areas.1 (,) 2 To improve the quality of surgery and prevent nerve damage, accurate intraoperative anatomical orientation of autonomic nerve is essential.3 Thanks to advancement of the high-definition laparoscopic technology, even the finest nerve fibers deep in the pelvic cavity can be identified through illumination and magnification.4 We aim to present a surgical technique of using the autonomic nerves as landmarks to guide laparoscopic TME for distal rectal cancer, with the purpose of preventing autonomic nerve damage to the largest extent. METHODS: The video describes the technique of performing nerve-guided laparoscopic TME in a 50-year-old man with a rectal cancer (7 cm from anal verge). Preoperative staging by endorectal ultrasound and pelvic magnetic resonance imaging is stage I rectal cancer (cT2N0M0). Five trocars (two 12 mm and three 5 mm) are used. All procedures are performed with conventional laparoscopic instruments. The sigmoid colon is mobilized using a medial approach. The superior hypogastric plexus lies just posterior to the inferior mesenteric artery (IMA) are clearly identified and protected. Then the root of the IMA is ligated and cut. The left Toldt space is dissected, followed by complete mobilization of the sigmoid colon. The superior hypogastric plexus nerve fibers combine to a strong pair of hypogastric nerves as they enter the pelvic cavity, and can be clearly identified when the mesorectum is lifted. Then the mesorectum is separated from the hypogastric nerves by sliding down along the nerves. Dissection of the mesorectum is continued in the loose areolar plane along the midline down to the sacrococcygeal junction. Then the mesorectum is dissected laterally from posterior midline up to 9 o'clock on the left and to 3 o'clock on the right side. The splanchnic nerves can be identified as they swing from the sacrum and straight into the pelvic plexus. The peritoneum is dissected in an arc line about 0.5 cm above the line of rectovesical pouch. After the anterior side of the rectum is mobilized, the mesorectum is dissected along the seminal vesicles downward and sideward to the lateral margin. The neurovascular bundle of Walsh at the anterolateral side of the rectum is clearly identified and protected. The mobilization of the mesorectum ceases at the tendinous arch of levator ani. Then the rectum is only fixed to the pelvic side wall by its lateral ligaments, which are consisted by rectal branch of the inferior pelvic plexus and vessels. Thus care should be taken to cut only those rectal nerve fibers, leaving the inferior pelvic plexus intact. The mesorectum is divided 5 cm distal to the lesion with one firing of an endoscopic stapler. The specimen is extracted through a 3 cm transumbilical laparotomy. End-to-end anastomosis using a circular stapler is performed intra-abdominally. RESULTS: There were no intraoperative complications. The operating time was 160 min. Blood loss was 20 mL. The patient underwent an uneventful recovery and was discharged home on postoperative day 6. Final pathology was pT2N0M0. At 6-month follow-up, the patient had no urogenital dysfunctions. CONCLUSIONS: Nerve-guided laparoscopic total mesorectal excision for distal rectal cancer is safe and feasible. This technique should be considered whenever possible as a means to prevent autonomic nerve damage and subsequent loss of urogenital function.

Single incision versus conventional multiport laparoscopic appendectomy: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: The efficacy of single incision laparoscopic appendectomy (SILA) in comparison with conventional multiport laparoscopic appendectomy (CMLA) has not been conclusively determined. METHODS: A systematic literature review (Medline, EMBASE, Science Citation Index, and Cochrane Central Register of Controlled Trials) was performed. Meta-analyses of randomized controlled trials (RCTs) comparing SILA with CMLA were carried out by RevMan 5.0 software. RESULTS: Eleven RCTs comparing SILA and CMLA were included. Overall, 1,216 patients were operated on: 611 cases by SILA versus 605 cases by CMLA. Compared with CMLA, SILA was associated with increased procedural difficulty, prolonged procedural duration, shorter length of hospital stay, earlier return to normal activity and better cosmesis. There were no significant differences in postoperative pain scores and complication rates between SILA and CMLA. CONCLUSION: The current best evidence shows SILA holds the promise of improving postoperative recovery and cosmetic result with equal efficacy and safety, whereas it is associated with higher surgical difficulty with longer surgical time when compared with CMLA.

Function characterization of a glyco-engineered anti-EGFR monoclonal antibody cetuximab in vitro.

AIM: To evaluate the biochemical features and activities of a glyco-engineered form of the anti-human epidermal growth factor receptor monoclonal antibody (EGFR mAb) cetuximab in vitro. METHODS: The genes encoding the Chinese hamster bisecting glycosylation enzyme (GnTIII) and anti-human EGFR mAb were cloned and coexpressed in CHO DG44 cells. The bisecting-glycosylated recombinant EGFR mAb (bisec-EGFR mAb) produced by these cells was characterized with regard to its glycan profile, antiproliferative activity, Fc receptor binding affinity and cell lysis capability. The content of galactose-α-1,3-galactose (α-Gal) in the bisec-EGFR mAb was measured using HPAEC-PAD. RESULTS: The bisec-EGFR mAb had a higher content of bisecting N-acetylglucosamine residues. Compared to the wild type EGFR mAb, the bisec-EGFR mAb exhibited 3-fold higher cell lysis capability in the antibody-dependent cellular cytotoxicity assay, and 1.36-fold higher antiproliferative activity against the human epidermoid carcinoma line A431. Furthermore, the bisec-EGFR mAb had a higher binding affinity for human FcγRIa and FcγRIIIa-158F than the wild type EGFR mAb. Moreover, α-Gal, which was responsible for cetuximab-induced hypersensitivity reactions, was not detected in the bisec-EGFR mAb. CONCLUSION: The glyco-engineered EGFR mAb with more bisecting modifications and lower α-Gal content than the approved therapeutic antibody Erbitux shows improved functionality in vitro, and requires in vivo validations.

Retrograde vs Conventional Dissection Technique in Pancreaticoduodenectomy: A Pilot Study.

IMPORTANCE: A retrograde dissection technique of pancreaticoduodenectomy in a caudocranial direction has been described recently. OBSERVATIONS: Fifteen consecutive patients who underwent retrograde pancreaticoduodenectomy were compared with 15 consecutive patients operated on through a conventional approach. The mean (SD) intraoperative blood loss was 407 (202) mL in the retrograde group compared with 423 (253) mL in the conventional group (P = .84). The mean (SD) operative duration was 255 (57) minutes in the retrograde group compared with 264 (54) minutes in the conventional group (P = .66). The overall morbidity was 7 of 15 patients (47%) in the retrograde group and 6 of 15 (40%) in the conventional group (P > .99). Neither group had a positive resection margin or a perioperative death. CONCLUSIONS AND RELEVANCE: The retrograde dissection technique had no significant difference in perioperative outcomes compared with the conventional dissection technique and could serve as an alternative dissection approach in pancreaticoduodenectomy.

EGFR-mediated G1/S transition contributes to the multidrug resistance in breast cancer cells.

Despite the improvement of strategies against cancer therapy, the multidrug resistance (MDR)is the critical problem for successful cancer therapy. Recurrent cancers after initial treatment with chemotherapy are generally refractory to second treatments with these anticancer therapies. Therefore, it is necessary to elucidate the therapy-resistant mechanism for development of effective therapeutic modalities against tumors. Here we demonstrate a phase-specific chemotherapy resistance due to epidermal growth factor receptor (EGFR) in human breast cancer cells. Thymidine-induced G1-arrested cultures showed upregulated chemosensitivity, whereas S-phase arrested cells were more resistant to chemotherapeutic agents. Overexpression of EGFR promoted the MDR phenotypes in breast cancer cells via accelerating the G1/S phase transition, whereas depletion of EGFR exerted the opposite effects. Furthermore, CyclinD1, a protein related to cell cycle, was demonstrated to be involved in above EGFR-mediated effects since EGFR increased the expression of CyclinD1, and the specific RNA interference against CyclinD1 could primarily abolish the EGFR-induced MDR phenotypes. These data provide new insights into the mode by which MDR breast cancers evade cytoxic attacks from chemotherapeutic agents and also suggest a role for EGFR-CyclinD1 axis in this process.

Identification and assessment of new biomarkers for colorectal cancer with serum N-glycan profiling.

BACKGROUND: The objectives of this study were to identify and validate the diagnostic value of N-glycan markers in colorectal cancer (CRC) and to uncover their underlying molecular mechanism. METHODS: In total, 347 individuals, including patients with CRC, patients with colorectal adenoma, and healthy controls, were divided randomly into a training group (n = 287) and retrospective validation groups (n = 60). Serum N-glycan profiling was analyzed by DNA sequencer-assisted/flurophore-assisted carbohydrate electrophoresis (DSA-FACE). Two diagnostic models were constructed based on N-glycan profiling with logistic stepwise regression. The diagnostic performance of each model was assessed further in retrospective, prospective (n = 43), and follow-up (n = 46) cohorts. Lectin blot and reverse transcriptase-polymerase chain reaction were used to analyze the total core-fucosylated residues and molecular expression involved in core-fucosylation modifications in CRC. RESULTS: Two diagnostic models designated CRCglycoA and CRCglycoB were constructed to differentiate CRC from normal and adenoma, respectively. The areas under the receiver operating characteristic curves (AUC) of both CRCglycoA and CRCglycoB were higher than the AUC of carcinoembryonic antigen (CEA) (CRCglycoA, 0.92 vs 0.81; CRCglycoB, 0.81 vs 0.73). The sensitivity and accuracy of CRCglycoA improved from 21.7% to 25% and from 11.63% to 18% in the training cohort, the retrospective cohort, and the prospective cohorts compared with the sensitivity and accuracy of CEA. The sensitivity of CRCglycoB improved from 20% to 28.23%. Both altered N-glycans, and results from the diagnostic models were reversed after curative surgery. The level of total core fucose residues and fucosyltransferase were decreased significantly in CRC. CONCLUSIONS: The current results indicated that the N-glycan markers based diagnostic models are new, valuable, noninvasive alternatives for identifying CRC. The authors concluded that decreased fucosyltransferase may be responsible for decreased levels of total core-fucosylated modification in both tissues and serum from patients with CRC.

Cellular prion protein promotes glucose uptake through the Fyn-HIF-2α-Glut1 pathway to support colorectal cancer cell survival.

Cellular prion protein (PrPc) is a glycosylphosphatidylinositol-anchored membrane protein that has various physical functions, including protection against apoptotic and oxidative stress, cellular uptake of copper ions, transmembrane signaling, and adhesion to the extracellular matrix. In this study, we show that PrPc is highly expressed in colorectal adenocarcinomas. Transcriptome profiling of PrPc-depleted DLD-1 cells revealed downregulation of glucose transporter 1 (Glut1). PrPc is shown to be involved in regulating Glut1 expression through the Fyn-HIF-2α pathway. As Glut1 is the natural transporter of glucose and is required for the high glycolytic rate seen in colorectal tumors, silencing of PrPc reduced the proliferation and survival rate of colorectal cancer cells in vitro. In vivo, knockdown of PrPc by hydrodynamic injection with a cocktail of PrPc-shRNA-encoding plasmids also inhibited tumorigenicity in a xenograft model in nude mice. In summary, our data characterize a novel molecular mechanism that links PrPc expression to the regulation of glycolysis. Targeting PrPc will therefore be a promising strategy to overcome the growth and survival advantage in colorectal tumors.

Increased expression of annexin A1 is correlated with K-ras mutation in colorectal cancer.

The activation of K-ras gene and expression of annexin A1 play an important role in colorectal tumorigenesis. We initiated this study to analyze the possible relationship between the annexin A1 expression and the K-ras mutation status in colorectal cancer. K-ras mutations are present in one fourth to one half of colorectal cancers. Annexin A1, a 37-kDa calcium- and phospholipid-binding protein, is over-expressed in colorectal cancers and may be involved in invasive tumor growth and metastasis. Here, we examined twenty paired specimens of colorectal cancer and adjacent normal tissues for K-ras mutations and annexin A1 expression. Sequencing analysis of codons 12 and 13 of K-ras revealed the presence of K-ras mutations in six colorectal cancer tissue specimens (30%). RT-PCR and immunoblotting studies further found that the expression levels of annexin A1 mRNA and protein were increased (2.9-fold and 1.7-fold, respectively) in colorectal cancers harboring K-ras codon 12 or codon 13 mutation compared with adjacent normal tissues (P < 0.05). In colorectal cancer tissues with wild-type K-ras, 12 (85.7%) specimens showed reduced expression of annexin A1 (0.48-fold and 0.81-fold, respectively). No significant association was found between K-ras mutations or annexin A1 over-expression and demographic or other clinicopathological parameters such as gender, differentiation or metastasis. However, a significant and positive correlation was identified between K-ras mutations and annexin A1 over-expression. Our findings indicate that annexin A1 could be implicated in colorectal cancer development and progression and could be of potential use as a predictive marker for guiding targeted therapy for colorectal cancer.

CTLA-4 +49A>G polymorphism is associated with the risk but not with the progression of colorectal cancer in Chinese.

PURPOSE: Colorectal cancer (CRC) is one of the most common malignancies in the world and a multipathway disease. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is a potent immunoregulatory molecule that suppresses antitumor response by down-regulating T-cell activation. The most studied +49A>G polymorphism of CTLA-4 gene has been associated with several autoimmune or cancer diseases. Our aim was to investigate the association between this genetic variant and the risk as well as progression of colorectal cancer in Chinese. METHODS: We conducted a case-control study of 124 colorectal cancer cases and 407 healthy controls. DNA was extracted from blood specimens, and +49A>G polymorphism in the CTLA-4 gene was genotyped by polymerase chain reaction-ligation detection reaction (PCR-LDR). RESULTS: In our study group, the frequency of AG or GG or carrying at least one G allele at position +49 was significantly different in colorectal cancer patients and the control group, indicating that the risk of CRC was significantly higher among subjects with the AG or GG genotype or carrying at least one G allele at position +49 than among the subjects with the AA genotype. However, we observed no association between CTLA-4 +49A>G polymorphism and the progression of CRC. Interestingly, the CTLA-4 +49A allele was in non-significantly higher numbers in CRC patients with distant metastasis. CONCLUSIONS: Our results suggested that CTLA-4 +49A>G polymorphism was associated with an increased risk of colorectal cancer, but this polymorphism did not play an important role in the progression of CRC in Chinese.