Circulating microRNA-1290 as a novel diagnostic and prognostic biomarker in human colorectal cancer.

BACKGROUND: Circulating microRNAs (miRNAs) are attracting major interest as potential non-invasive biomarkers for colorectal cancer (CRC). This study aimed to identify a novel serum miRNA biomarker for the early detection and/or evaluating prognosis of CRC patients. PATIENTS AND METHODS: Comprehensive miRNA array analysis was carried out using serum samples from patients with colorectal neoplasia and healthy controls. Next, to verify whether the candidate miRNA possessed a secretory potential, we screened miRNA expression levels in culture medium from 2 CRC cell lines, followed by serum analysis from 12 stage IV CRC, 12 adenoma, and 12 control subjects. Thereafter, we validated expression of candidate miRNAs in 179 primary CRC tissues, as well as serum samples from an independent cohort of 211 CRCs, 56 adenomas, and 57 control subjects. RESULTS: Through microarray analysis, we identified significantly higher levels of miRNA-1290 (miR-1290) in serum from patients with colorectal adenomas and cancers. We verified miR-1290 overexpression in serum of CRC patients in a training cohort. In the validation cohort, serum miR-1290 levels were significantly up-regulated in patients with colorectal adenomas (P < 0.0001) and cancers (P < 0.0001). Serum miR-1290 levels could robustly distinguish adenoma [area under the curve (AUC) = 0.718] and CRC patients (AUC = 0.830) from normal subjects. High miR-1290 expression in serum and tissue was significantly associated with tumor aggressiveness and poor prognosis. Moreover, serum miR-1290 levels were an independent prognostic factor [hazard ratio (HR) = 4.51; 95% confidence interval (CI) = 1.23-23.69; P = 0.0096] and an independent predictor for tumor recurrence (hazard ratio = 3.92; 95% confidence interval = 1.11-25.14; P = 0.032) in CRC. CONCLUSIONS: Serum miR-1290 is a novel biomarker for early detection, recurrence, and prognosis in CRC.

Brain-derived neurotrophic factor/tropomyosin-related kinase B pathway in gastric cancer.

BACKGROUND: Brain-derived neutrophic factor (BDNF) is a member of the neutrophin family that is known to activate the high-affinity tropomyosin-related receptor kinase B (TrkB). This study aimed to clarify the clinical and biological significance of the BDNF/TrkB pathway in gastric cancer. METHODS: We analysed BDNF and TrkB expression in gastric cancer samples by real-time reverse transcription PCR and immunohistochemistry. To investigate the biological role of BDNF/TrkB axis, recombinant human BDNF (rhBDNF) and the Trk antagonist K252a were used for in vitro and in vivo analysis. RESULTS: The BDNF expression at the invasive front of primary tumours was significantly elevated compared with that in the tumour core and adjacent normal mucosa. Increased BDNF expression at the invasive front was significantly correlated with factors reflecting disease progression, and poor prognosis. Increased co-expression of the BDNF/TrkB axis was significantly correlated with poor prognosis. Gastric cancer cells expressed BDNF, and administration of rhBDNF promoted proliferation, migration, invasion, and inhibition of anoikis. These effects were generally inhibited by K252a. In an in vivo assay, BDNF(+)/TrkB(+) gastric cancer cells injected into nude mice established peritoneal dissemination, whereas K252a inhibited tumour growth. CONCLUSION: The BDNF/TrkB pathway might be deeply involved in gastric cancer disease progression.

Loss of tumoral expression of soluble IL-6 receptor is associated with disease progression in colorectal cancer.

BACKGROUND: Interleukin-6 (IL-6) binds both the membrane and soluble forms of the IL-6 receptor (sIL-6R), which induces a complex with gp130, and proliferation of tumour cells. The aim of this study is to clarify the relationship between tumoral sIL-6R expression and disease progression in colorectal cancer patients. METHODS: We measured tissue concentrations of sIL-6R in tumour and normal mucosa from 161 colorectal cancer patients undergoing surgery, and in supernatants from colon cancer cell lines. The expression of IL-6, IL-6R and gp130 was evaluated by immunohistochemical analysis. RESULTS: Loss of tumour expression of sIL-6R as defined by sIL-6R Ca/N ratio <1.0 was significantly associated with factors reflecting disease progression, and was an independent prognostic factor not only in all the patients in this study, but also in the patients with curative intent. Colon cancer cell lines produced sIL-6R in vitro, and the production of sIL-6R in cancer cell lines was stimulated by cytokine stimulation. Immunohistochemistry revealed that loss of tumour expression of sIL-6R was significantly inversely correlated with intense IL-6 expression in the cytoplasm of cancer cells. In addition, tumoral IL-1beta expression was significantly correlated with sIL-6R expression. CONCLUSION: Loss of tumour expression of sIL-6R is associated with colorectal cancer disease progression.

Schedule-dependent cytotoxicity of 5-fluorouracil and irinotecan in p53 mutant human colon cancer.

IFL [irinotecan (CPT-11), 5-fluorouracil (5-FU), and folinic acid] is one of the treatments for metastatic colorectal cancer. We evaluated cytotoxic effects of a sequentially administered a combination of 5-FU with CPT-11 in human p53 mutant colon cancer. Sequential combination of 5-FU and CPT-11 in human colon cancer SW480 cells using a WST-8 colorimetric assay was studied. Cytotoxicity and cell cycle distribution for each drug were evaluated using an apoptosis assay and flow cytometry. Potential mechanisms of sequence-dependent cytotoxic effects were investigated using microarrays. Cytotoxicity of 5-FU (10, 100, 1000 microM) combined with subsequent use of CPT-11 (1 microM) was significantly greater than the reverse sequence of CPT-11 followed by 5-FU (p < 0.05). Following 24 hrs treatment with 5-FU (0.1-100 microM), no significant apoptosis was observed. In contrast, apoptosis was significantly induced after 24 hrs treatment with CPT-11 (1 and 10 microM). Flow cytometric analysis showed no significant difference in cell cycle distribution between different drug concentrations. We demonstrated up-regulation of 85 genes and down-regulation of 21 genes correlating with sequence-dependent cytotoxicities of 5-FU and CPT-11. The superiority of 5-FU-CPT-11 sequence was proven for p53 mutant colon cancer, SW480. Treatment with 5-FU followed by CPT-11 administration may be the optimal sequence for IFL treatment of metastatic colon cancers.

Perioperative allogeneic blood transfusion, the related cytokine response and long-term survival after potentially curative resection of colorectal cancer.

AIMS: It is still debated whether perioperative blood transfusion alters the incidence of disease recurrence or otherwise affects the prognosis after curative resection of malignant tumours. We conducted a prospective observational study of patients with colorectal cancer to provide data on the effect of blood transfusion and the related perioperative cytokine response on long-term prognosis. MATERIALS AND METHODS: Perioperative blood samples were obtained from 117 patients with colorectal cancer undergoing potentially curative resection. Factors associated with perioperative blood transfusion were assessed, and their relationship with early postoperative systemic responses of tumour growth factors and long-term prognosis were evaluated. RESULTS: Independent factors associated with perioperative blood transfusion were preoperative anaemia, operative blood loss and the development of postoperative infectious complication. The patients receiving transfusions were subdivided according to the independent factors. Group A comprised 19 patients who received blood transfusions because of preoperative anaemia and Group B comprised 16 patients who received blood transfusions because of excessive operative blood loss. Group B patients showed exaggerated postoperative systemic induction of interleukin (IL)-6 and IL-6-triggered tumour growth factors, such as hepatocyte growth factor and vascular cell adhesion molecule-1. Intraoperative blood transfusion under intense surgical stress was associated with poor prognosis, whereas preoperative blood transfusion for correcting anaemia or intraoperative blood transfusion under less invasive surgery was not associated with survival. Multivariate analysis using the Cox proportional hazards method showed that a significant independent risk was demonstrated for blood transfusion, T stage, lymph-node metastasis and perioperative peak levels of IL-6. CONCLUSION: Blood transfusion and intense surgical stress might synergistically affect the long-term prognosis after curative resection of colorectal cancer. Postoperative exaggerated systemic inductions of IL-6 may indicate the critical situation that could lead to disease recurrence.

Safety and results of dobutamine stress echocardiography in women versus men and in patients older and younger than 75 years of age.

The purpose of this retrospective study was to examine 732 consecutive patients who underwent dobutamine stress echocardiography (DSE) in order to compare the safety and result profiles of this test between women versus men and in patients > or = 75 and < 75 years of age. Our study included 416 women (57%) and 316 men (43%; mean age 62 +/- 12 years [range 16 to 93]). Patients were divided into 3 age groups: (1) group I (n = 179): < 55 years (mean 47 +/- 6), (2) group II (n = 447): 55 to 74 years (mean 64 +/- 5), and (3) group III (n = 106): > or = 75 years (mean 80 +/- 4). DSE was more likely to have negative results in women than in men (prevalence of positivity = 20% vs 31%, p = 0.001), but DSE had a similar safety profile in both genders. Women required lower doses of dobutamine and atropine to reach an end point. There was a similar incidence of test positivity in older and younger patients (23% in group I, 24% in group II, and 30% in group III, p = NS). DSE was generally a safe test in patients > or = 75 years, but there was a different safety profile in the elderly group compared with younger patients--specifically, more frequent asymptomatic hypotension (7% in group I, 13% in group II, and 25% in group III, p = 0.0002) and ventricular arrhythmias (26% in group I, 30% in group II, and 41% in group III, p = 0.04), but less frequent chest pain (32% in group I, 23% in group II, and 17% in group III, p = 0.009). Multivariate analysis suggested that the baseline usage of beta blockers was also a major determinant of the safety and ischemia profile during DSE. In conclusion, there were significant gender- and/or age-specific differences in the safety and test result profile of DSE. These differences should be considered when performing or interpreting DSE, particularly in women and in patients aged > or = 75 years.

Stroke volume generation of the left ventricle and its relation to chamber shape in normal subjects and patients with mitral or aortic regurgitation.

The total stroke volume of the left ventricle (LV) is equal to the sum of the regional cavity shrinkage. Since nonuniformity of regional wall motion in LV has been well documented even in normal subjects, the extent of the contribution of each region to total stroke volume cannot be easily determined. To assess the left ventricular regional contributions to total stroke volume under normal conditions and in compensated chronic mitral or aortic regurgitation, LV cineangiograms were analyzed in 14 normal subjects (N), 8 patients with mitral regurgitation (MR) and 10 patients with aortic regurgitation (AR). We assumed that the LV cavity could be viewed as a stack of 30 half-cylindrical discs, 15 in the anterior and 15 in the inferior wall regions. LV chamber shape was more spherical in MR than in N, but was more conical in AR. Percent regional hemichordal shortening was significantly decreased in the anterobasal and anteroapical walls in AR, but was similar between N and MR. The regional contribution to total stroke volume showed a significant quadratic correlation with the end-diastolic regional shape index (N, r = 0.87; MR, r = 0.79; AR, r = 0.90), which was defined as the regional hemiaxial length divided by the LV long-axis length, but was not correlated with percent regional hemichordal shortening. Therefore, stroke volume is generated mainly in the mid-ventricular portion in N and MR, but in the basal portion in AR due to the characteristic change in cavity shape.

Assessment of flow profile of left anterior descending coronary artery in hypertrophic cardiomyopathy by transesophageal pulsed Doppler echocardiography.

This study assessed the flow velocity profiles of the left anterior descending coronary artery (LAD) in 7 patients with nonobstructive hypertrophic cardiomyopathy (HC) and in 6 normal subjects by transesophageal pulsed Doppler echocardiography, and evaluated their characteristics and the hemodynamic determinants. Systolic peak flow velocity of the LAD (7 +/- 30 cm/sec) was significantly lower in patients with HC than in normal subjects (34 +/- 11 cm/s, p < 0.05), and there was a significant inverse correlation between systolic peak flow velocity and the thickness of the ventricular septum (r = 0.81, p < 0.01). In 2 cases of HC with ventricular septal thickness of > 20 mm, a remarkable systolic reverse flow was observed in the LAD. However, there was no significant difference in diastolic peak flow velocity between HC and normal subjects. During early diastole, the acceleration time of LAD flow velocity was significantly prolonged (210 +/- 67 vs 95 +/- 15 ms, p < 0.01) and the acceleration rate was significantly decreased (3.6 +/- 2.0 vs 6.6 +/- 1.8 m/s2, p < 0.02) in patients with HC. The time constant of the left ventricular pressure decay was significantly prolonged in patients with HC (55 +/- 6 ms) compared with normal subjects (39 +/- 2 ms, p < 0.001). In HC, increased intramural perivascular pressure of the thickened ventricular septum during systole may be attributed to systolic LAD flow pattern. However, the early and mid-diastolic LAD flow pattern may be affected by impaired left ventricular relaxation.

[Atrial septal defect diagnosed and quantitatively-evaluated by transesophageal two-dimensional Doppler echocardiography].

Transesophageal two-dimensional (2-D) echocardiography (TEE: horizontal sector scan) combined with the pulsed Doppler method was performed to determine the size of atrial septal defect (ASD) and to measure directly shunt flow signals through the defects in six ASD patients (32 +/- 16 yrs) confirmed by cardiac catheterization. The size of the defect in the horizontal dimension was measured by TEE; the vertical dimension of the defect was determined from the distance of the transesophageal probe positions of the rostral and caudal margins of the defect. The size of defect determined by TEE was compared with that observed at surgery. Shunt flow signals were recorded by the pulsed Doppler technique by setting the sample volume at the center of the defect. Left-to-right shunt flow was determined as follows: shunt flow volume (ml/min) = mean velocity (cm/s) x the area of a defect (cm2) x 60. The shunt flow was compared with that obtained by the Fick's method. In all patients, TEE accomplished unequivocal visualization of a defect. The defect sizes by TEE correlated well with measurements obtained at surgery (r = 0.66). A clear laminar shunt flow with its peak in late systole and atrial systole was observed. Significant correlations were obtained between shunt volumes by TEE and those by the Fick's method (r = 0.91, p less than 0.05). Thus, TEE proved a useful method for diagnosing ASD and for evaluating shunt flow volumes.

[Detection of mural thrombi and analysis of blood flow velocities in the left atrial appendage using transesophageal two-dimensional echocardiography and pulsed Doppler flowmetry].

To correlate blood flow velocities with thrombogenesis in the left atrium (LA) and left atrial appendage (LAA), we performed transesophageal two-dimensional echocardiography (Eso 2-D Echo) combined with pulsed Doppler flowmetry, which was developed in our laboratory. Thirty-eight patients were studied; 1) 15 who had sinus rhythm including four with mitral stenosis (MS) and 11 normal subjects, and 2) 23 with atrial fibrillation (Af). The patients with Af were classified as lone Af (nine cases); Af-CI: Af with cerebral infarction having no MS (four cases); and Af-MS: Af with MS (10 cases). In four of 10 patients with Af-MS, mural thrombi were detected in the LA or LAA by Eso 2-D Echo, but they were not visualized by conventional echocardiography. In lone Af and Af-CI, however, abnormal echoes in the LAA were not observed by Eso 2-D Echo. Thus, Eso 2-D Echo proved superior to conventional 2-D echocardiography in detecting mural thrombi in the LA or LAA. In sinus rhythm, a biphasic flow pattern followed the P wave on the ECG. It was observed in the vicinity of the junction between the LA and LAA. In Af a flow with a saw-tooth appearance was observed throughout the cardiac cycle. The peak flow velocity in the LAA was significantly less in Af than in sinus rhythm (p less than 0.05). Especially in Af-MS, the peak flow velocity was markedly decreased (1 +/- 4 cm/sec: mean +/- SD) compared with those of the other Af groups (p less than 0.01), and it was significantly less in Af-CI (11 +/- 5 cm/sec) than in patients with lone Af (21 +/- 9 cm/sec) (p less than 0.05). These results indicate that analysis of blood flow velocities in the LAA by Eso 2-D Echo is of great value in assessing thrombogenesis in the LAA, and the patients with Af, even without MS, who have markedly reduced peak flow velocities in the LAA, should be prophylactically anticoagulated, because stagnation of blood is strongly suspected.

A case of left ventricular aneurysm associated with an anomalous coronary artery.

A 54-year-old man presented with continual angina pectoris at rest, associated with an anomalous coronary artery. He also had an aneurysm at the submitral region of the left ventricular postero-lateral wall, without evidence or prior myocardial infarction, which showed hypokinetic inward motion during systole. We assume that this was a rare case of left ventricular aneurysm without prior myocardial infarction, the etiology which might related to the anomalous coronary artery.