Small Extracellular Vesicles (sEVs) Biogenesis Molecular Players Are Associated with Clinical Outcome of Colorectal Cancer Patients.

A growing number of studies have shed light on the role of small extracellular vesicles (sEVs), including exosomes, in colorectal cancer (CRC). Available data regarding the clinical significance of molecular players in CRC, implicated in sEVs biogenesis, is limited. In this study, we assessed the expression of the most important genes which are implicated in sEVs biogenesis and their association with sEVs plasma levels, investigated with a double sandwich ELISA assay, as well as with the clinical outcome of patients with CRC. Our study shows that RAB27A, RAB27B, RAB2B, and RAB3B mRNA levels were lower in tumor tissues compared to tumor adjacent, non-malignant tissues (p < 0.001, p = 0.009, p = 0.011, and p < 0.001, respectively). In addition, high tumor expression of RAB27A, RAB27B, RAB9A, RAB11B, and STX1A was favorable of a 5-year survival (p = 0.038, p = 0.015, p = 0.008, p = 0.002, and p = 0.028, respectively). Furthermore, patients with adenomas had lower overall plasma sEVs concentrations, compared to healthy volunteers (p = 0.026), while no statistically significant differences were observed in the overall or tumor-derived plasma sEVs concentration (p = 0.885 and p = 0.330, respectively) of CRC patients. In conclusion, sEVs biogenesis has a potentially significant role in CRC, with RAB27A, RAB27B, RAB9A, RAB11B, and STX1A having a promising role in survival outcomes.

Differentially Methylated Ultra-Conserved Regions Uc160 and Uc283 in Adenomas and Adenocarcinomas Are Associated with Overall Survival of Colorectal Cancer Patients.

: Deregulation of the transcribed ultra-conserved regions (T-UCRs) Uc160, Uc283, and Uc346 has been reported in colorectal cancer (CRC) recently. Here, we investigated promoter methylation of these T-UCRs during the adenoma-carcinoma sequence and their clinical significance in CRC patients. Methylation levels were assessed in CRC, adenomas, infiltrated lymph nodes, and metastatic tissue specimens. In situ hybridization was performed in representative tissue specimens. T-UCRs expression levels were also evaluated in HT-29 colon cancer cells before and after the acquired resistance to 5-fluorouracil (5-FU) and oxaliplatin. A gradual increase in T-UCRs methylation levels from hyperplastic polyps to adenomas and to in situ carcinomas (ISC) and a gradual decrease from ISC to infiltrative and metastatic carcinomas was observed (p < 0.001 for Uc160 and Uc283, p = 0.018 for Uc346). Uc160 and Uc283 methylation was associated with the grade of dysplasia in adenoma specimens (p = 0.034 and p = 0.019, respectively). Furthermore, higher Uc160 methylation, mainly in stage III and IV patients, was related to improved overall survival (OS) in univariate (p = 0.009; HR, 0.366) and multivariate analysis (p = 0.005; HR, 0.240). Similarly, higher methylation of Uc283 was associated with longer OS (p = 0.030). Finally, T-UCRs expression was significantly reduced in HT-29 cells after resistance to chemotherapy. This study suggests that promoter methylation of Uc160, Uc283, and Uc346 is altered during CRC development and that Uc160 and Uc283 methylation may have prognostic significance for CRC patients.

Deregulation of methylation of transcribed-ultra conserved regions in colorectal cancer and their value for detection of adenomas and adenocarcinomas.

Expression of Transcribed Ultraconserved Regions (T-UCRs) is often deregulated in cancer. The present study assesses the expression and methylation of three T-UCRs (Uc160, Uc283 and Uc346) in colorectal cancer (CRC) and explores the potential of T-UCR methylation in circulating DNA for the detection of adenomas and adenocarcinomas. Expression levels of Uc160, Uc283 and Uc346 were lower in neoplastic tissues from 64 CRC patients (statistically significant for Uc160, p<0.001), compared to non-malignant tissues, while methylation levels displayed the inverse pattern (p<0.001, p=0.001 and p=0.004 respectively). In colon cancer cell lines, overexpression of Uc160 and Uc346 led to increased proliferation and migration rates. Methylation levels of Uc160 in plasma of 50 CRC, 59 adenoma patients, 40 healthy subjects and 12 patients with colon inflammation or diverticulosis predicted the presence of CRC with 35% sensitivity and 89% specificity (p=0.016), while methylation levels of the combination of all three T-UCRs resulted in 45% sensitivity and 74.3% specificity (p=0.013). In conclusion, studied T-UCRs' expression and methylation status are deregulated in CRC while Uc160 and Uc346 appear to have a complicated role in CRC progression. Moreover their methylation status appears a promising non-invasive screening test for CRC, provided that the sensitivity of the assay is improved.

The greatly increased amounts of accumulated versican and decorin with specific post-translational modifications may be closely associated with the malignant phenotype of pancreatic cancer.

Pancreatic carcinoma (PC) is a cancer type with highly malignant growth and dissemination pattern of which the mechanisms are poorly understood. However, the malignant phenotype is closely linked to extracellular matrix (ECM) of which proteoglycans (PGs) and hyaluronan (HA) play a crucial role in the control of tumor progression and metastasis. In this study, we demonstrated that versican and decorin, two different PGs with contradictory roles and functions in the pathobiology of cancer, were the main matrix PGs in PC presenting a great increase 27- and 7-fold, respectively, in comparison to normal pancreas (NP). PC was characterized by the disproportional increase of versican compared to decorin, about 4 to 1, with a concurrent increase of HA, which may be closely associated with the growth and aggressiveness of this carcinoma. Significant specific post-translational modifications were also observed in both versican and decorin regarding the type, hydrodynamic size, sulfation pattern and extent of uronate epimerization of their glycosaminoglycan chains (GAGs). In particular, chondroitin sulphate (CS) was the predominant GAG type in both PC-associated versican and decorin. The CS of PC-decorin was increased 11-fold, compared to NP in which dermatan sulfate (DS) was the predominant GAG type in both PGs. The sulfation pattern of GAG chains was significantly altered in PC, since 6-sulfated disaccharides predominated in both versican and decorin with a marked presence of non-sulfated disaccharides accompanied by lower hydrodynamic sizes of both CS and DS chains compared to NP. In conclusion, all these findings agree with the highly malignant phenotype of this cancer and, thus, more studies need to be addressed on the roles of the post-translational modifications of versican and decorin in the biology of cancer.

Laparoscopic cholecystectomy: a report from a single center.

AIM: To review and evaluate our experience in laparoscopic cholecystectomy. METHODS: A retrospective analysis was performed on data collected during a 13-year period (1992-2005) from 1220 patients who underwent laparoscopic cholecystectomy. RESULTS: Mortality rate was 0%. The overall morbidity rate was 5.08% (n = 62), with the most serious complications arising from injuries to the biliary tree and the cystic artery. In 23 (1.88%) cases, cholecystectomy could not be completed laparoscopically and the operation was converted to an open procedure. Though the patients were scheduled as day-surgery cases, the average duration of hospital stay was 2.29 d, as the complicated cases with prolonged hospital stay were included in the calculation. CONCLUSION: Laparoscopic cholecystectomy is a safe, minimally invasive technique with favorable results for the patient.

The survivin -31 snp in human colorectal cancer correlates with survivin splice variant expression and improved overall survival.

BACKGROUND: Survivin is involved in the regulation of cell division and survival, two key processes in cancer. The majority of studies on survivin in colorectal cancer (CRC) have focused on protein expression and less is known about the expression of survivin splicing variants or survivin gene polymorphisms in CRC. In the present study, the mRNA levels of the five known isoforms of survivin as well as survivin protein were assessed in matched normal and neoplastic colorectal tissue. Moreover, the 9386 C/T and -31 G/C polymorphisms were investigated. METHODS: Quantitative RT-PCR was used to assess mRNA levels in fresh/frozen tissue samples. Protein levels were immunohistochemically evaluated on formalin-fixed paraffin-embedded tissue sections. Individuals were genotyped using real time PCR. RESULTS: Expression of all 5 survivin splice variants as well as survivin protein was elevated in colorectal carcinomas compared to normal tissue. Specific splice variant expression differentially correlated with clinicopathological parameters. Furthermore, both snps correlated with splice variant levels or their ratios in colorectal carcinomas while the -31 G/C snp may be related to CRC development and improved overall survival. CONCLUSION: Our results support a role of survivin in colorectal carcinogenesis while the -31 G/C snp may constitute a marker of survival.

The survivin -31 snp in human colorectal cancer correlates with survivin splice variant expression and improved overall survival.

BACKGROUND: survivin is involved in the regulation of cell division and survival, two key processes in cancer. The majority of studies on survivin in colorectal cancer (CRC) have focused on protein expression and less is known about the expression of survivin splicing variants or survivin gene polymorphisms in CRC. In the present study, the mRNA levels of the five known isoforms of survivin as well as survivin protein were assessed in matched normal and neoplastic colorectal tissue. Moreover, the 9386C/T and -31G/C polymorphisms were investigated. METHODS: quantitative RT-PCR was used to assess mRNA levels in fresh/frozen tissue samples. Protein levels were immunohistochemically evaluated on formalin-fixed paraffin-embedded tissue sections. Individuals were genotyped using real time PCR. RESULTS: expression of all 5 survivin splice variants as well as survivin protein was elevated in colorectal carcinomas compared to normal tissue. Specific splice variant expression differentially correlated with clinicopathological parameters. Furthermore, both snps correlated with splice variant levels or their ratios in colorectal carcinomas while the -31G/C snp may be related to CRC development and improved overall survival. CONCLUSION: our results support a role of survivin in colorectal carcinogenesis while the -31G/C snp may constitute a marker of survival.

Irinotecan/fluorouracil/leucovorin or the same regimen followed by oxaliplatin/fluorouracil/leucovorin in metastatic colorectal cancer.

BACKGROUND: This study reports the long-term follow-up of patients with metastatic colorectal cancer (CRC) participating in a randomised phase II study that compared the efficacy and toxicity of the combination of irinotecan (IRI), fluorouracil (FU) with leucovorin (LV) (arm A) versus sequential chemotherapy with IRI plus FU/LV followed by oxaliplatin (OXA) plus FU/LV (arm B) as first line therapy. MATERIALS AND METHODS: Intent-to-treat analysis was performed on 417 patients (211 in arm A and 206 in arm B). Treatment schedules of weekly IRI 80 mg/m(2) or OXA 45 mg/m(2) plus LV 200 mg/m(2) immediately followed by intravenous bolus FU 450 mg/m(2) for 6 weeks were followed by a 2-week rest period. Treatment continued for 4 cycles. Patients in arm A were treated with IRI/FU/LV for 4 cycles, while patients in arm B were initially treated with IRI/FU/LV for 2 cycles followed by sequential administration of 2 cycles of OXA/FU/LV. RESULTS: No significant difference emerged in overall response rate or overall survival. There was a difference in progression-free survival (median, 7.3 versus 8.2 months, p=0.040) in favour of arm B. Toxicity profiles were similar in both arms. CONCLUSION: IRI/FU/LV and IRI/FU/LV followed by OXA/FU/LV showed comparable activity with a manageable toxicity profile.

TGF-beta repressors SnoN and Ski are implicated in human colorectal carcinogenesis.

BACKGROUND: The TGF-beta signaling repressors SnoN and Ski have been critically implicated in human cancer. METHODS: To explore the role of SnoN and Ski in the development and progression of colorectal cancer we examined their protein expression profile by immunohistochemistry in a series of human colorectal adenomas, carcinomas and lymph node metastases. The mRNA expression of SnoN was also quantified by Real-Time RT-PCR. RESULTS: SnoN and Ski were overexpressed both in adenomas with severe dysplasia and colorectal carcinomas. Protein expression was cytoplasmic and nuclear with predominant cytoplasmic localization. The subcellular localization was related differently to pathologic variables of colorectal carcinomas. Although there was no significant association of protein levels with tumor invasion and metastasis, a significant correlation of nuclear SnoN and Ski with beta-catenin pathway was observed. Moreover, SnoN mRNA did not differ in carcinomas as compared to normal control and there was no correlation between SnoN protein and mRNA levels. CONCLUSION: Our findings suggest that SnoN and Ski exert oncogenic effects in human colorectal carcinogenesis and their overexpression is implicated in early stage disease.