Relationship between altered expression levels of MIR21, MIR143, MIR145, and MIR205 and clinicopathologic features of esophageal squamous cell carcinoma.

In spite of the undisputed importance of altered expression patterns of microRNAs (miRNAs) in various cancers, there is little information on the clinicopathologic significance of cancer-related miRNAs (MIR21, MIR143, MIR144, MIR145, and MIR205) in esophageal squamous cell carcinoma (ESCC). We examined the expression levels of the precursor and mature miRNA genes in ESCC using real-time polymerase chain reaction (PCR). We also investigated the mRNA expression levels of processing elements (RNASEN, DGCR8, and DICER1) that participate in miRNA-biogenesis pathway. Furthermore, we analyzed the relationships between the expression levels of these five miRNAs and the clinicopathologic parameters of ESCC patients. The expression levels of mature MIR21 and mature MIR145 were higher in ESCC than those in normal epithelium (P < 0.05). The mature/pre ratio of MIR21 in ESCC was higher than that in normal epithelium (P < 0.05). With regard to miRNA-processing elements, the expression level of RNASEN was higher in ESCC than in normal epithelium (P < 0.05). Furthermore, altered expression of these miRNAs was related to the clinicopathologic features of ESCC patients. The high expression of mature MIR21 and mature MIR205 was associated with lymph node positivity in ESCC patients (P < 0.05). The high levels of expression of mature MIR143 and mature MIR145 were associated with recurrence of metastasis in ESCC patients (P < 0.05). The findings may imply that miRNA biogenesis is aberrantly accelerated in ESCC. Analysis of the expression levels of miRNAs should provide useful information for evaluation of the staging, prognosis, and treatment of ESCC patients.

The role of simulator Promis2 in learning laparoscopic skill.

INTRODUCTION: Laparoscopic surgery is unique and complex in nature, so the training is necessary before proceeding to operation room. Many computer aided simulators have been developed for the purpose. Our objective is to assess the improvement of basic laparoscopic skills after training in simulator. METHODS: The fifth year medical students underwent training of three laparoscopic skills using Promis2 simulator twice weekly for 4-6 weeks. The skills are laparoscopic orientation, target pointing and objects transferring. Time, path length of instruments and economy of movements were recorded. The comparisons were made for these parameters between session first and the last using a Mann-Whitney U test. RESULTS: Ten volunteers completed the exercises in less time (186.3 +/- 55.4 seconds) than the first exercise (215.7 +/- 57.4 seconds) (P=0.0027). Both the right and left hand instrument path lengths were also improved from 4425.8 +/- 1284.3 mm in the first exercise to 3925.3 +/- 1313.6 mm in the last exercise in the left side (P=0.0219) and likewise from 4273.8 +/- 1859.4 mm to 3831.3 +/- 1717.4 mm in the right side (P=0.0027). Economy of the movement in the left handed instrument improved from 1114.4 +/- 453.5 mm in the first exercise to 966.8 +/- 411.1 mm in the last (P=0.0443) and in the right handed instrument from 845 +/- 398.8 mm to 771.4 +/- 370.5 mm according to the software of Promis2 simulator (P >0.005). CONCLUSIONS: Training in Promis2 simulator improves the basic laparoscopic skills. The candidates become consistently faster with shorter path lengths and had smoother instruments movements. They also became significantly more consistent in their performance.