Guangen Yang

Clinical significance of Neutrophil gelatinase-associated lipocalin(NGAL) expression in primary rectal cancer

BackgroundEmerging evidence has demonstrated that Neutrophil gelatinase-associated lipocalin (NGAL) is up-regulated in multiple malignancies, including oesophagus cancer, and plays a critical role in tumorigenesis and progression. However, till now, little is known about the role of NGAL in human rectal cancer. Its association with clinicopathologic characteristics and expression of MMP-9, one of its target genes, has not been reported systematically in rectal cancer. Therefore, to further determine the potential involvement of NGAL in rectal cancer, we have evaluated the expression level of NGAL mRNA by real time RT-PCR, and further elucidated the correlation of NGAL mRNA expression with clinicopathologic features and MMP-9 in rectal cancer.Methods100 paired samples of rectal cancer and adjacent normal tissues obtained from inpatients undergoing surgical operation were allocated into two groups (cancer group and control group). The mRNA expression of NGAL and MMP-9 was determined by real-time RT-PCR. The association between their expression and clinicopathological characteristics of rectal cancer were analysised.ResultsAmong the 100 rectal cancers, 69 cases of NGAL mRNA up-regulation were observed. NGAL mRNA up-regulation was positively correlated with MMP-9 (rs = 0.393, p < 0.001). In rectal cancer, NGAL mRNA overexpression was significantly associated with depth of invasion (p = 0.028), lymph node metastasis (p = 0.009), venous involvement (p = 0.023) and advanced pTNM stage (p = 0.011).ConclusionIn human rectal cancer, NGAL mRNA expression was elevated. NGAL mRNA up-regulation was correlated significantly with tumor progression and MMP-9 mRNA overexpression in rectal cancer, suggesting a more aggressive phenotype. NGAL could be used for rectal cancer characterization.

MicroRNA-24 inhibits serotonin reuptake transporter expression and aggravates irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disorder. MicroRNAs (miRNAs) have been widely demonstrated to take part in various physiological and pathological processes. In the present study, the role of miR-24 in the pathogenesis of IBS and the potential mechanism in this process were evaluated. Human intestinal mucosa epithelial cells of colon from IBS patients and healthy subjects were collected. An IBS mouse model was established with the induction of trinitro-benzene-sulfonic acid (TNBS). The expression levels of miR-24 and serotonin reuptake transporter (SERT) were analyzed using Real-time PCR and western blot in both human specimen and mice. miR-24 was upregulated in IBS patients and mice intestinal mucosa epithelial cells. Luciferase reporter assay showed that SERT was a potential target gene of miR-24. The treatment of miR-24 inhibitor increased pain threshold and nociceptive threshold levels and reduced MPO activity in proximal colon of IBS mice, and up-regulated the mRNA and protein expression levels of SERT in intestinal mucosa epithelial cells. miR-24 played a role in the pathogenesis of IBS probably through regulating SERT expression.

A novel therapeutic strategy using ultrasound mediated microbubbles destruction to treat colon cancer in a mouse model

The goal of this study was to determine whether ultrasound mediated microbubbles destruction (UMMD) could inhibit colon cancer growth in a mouse model. Six-week-old balb/c female nude mice were subcutaneously inoculated with HT29-GFP cells (HT29 cells labeled with green fluorescent dye) in axilla to establish a xenograft mouse model of colon carcinoma, which were randomly divided into five groups (n=10 each): group A (blank group): no treatment; group B (saline only); group C (saline+ultrasound exposure); group D (intravenous microbubbles only); and group E (intravenous microbubbles+ultrasound exposure). Treatment of each group was performed on days 20, 21, and 22 after inoculation. Tumor growth and metastatic spread were monitored by the whole-body fluorescent imaging, tumor volume growth and body weight growth curve were obtained as well. The mice were euthanized 30 days after treatment. Specimens of the tumor tissues were evaluated pathologically using light microscopy and transmission electron microscopy. Necrosis percentages, microvascular density and tumor cells damage of each tumor were assessed histologically. Our data indicate that: (1) tumor growth in group E (intravenous microbubbles+ultrasound exposure) was significantly decreased after four weeks post inoculation, compared with other control treatments (P<0.05); (2) the tumor weight at sacrifice in group E was significantly lower than that in other groups; (3) The intravenous microbubbles combined with ultrasound exposure treated mice showed significantly decreased expression levels of CD31. (4)The pathological changes of absence of nucleus membrane, chromatin condensation, mitochondrial vacuolation and hemorrhagic damage of microvessel were observed in the tumors of group E only, whereas these changes occurred rarely in other groups; and (5) no metastatic lesion was found in any group throughout this study using whole-body fluorescent imaging, and the skin of the mouse in group E was intact after UMMD treatment. Our results suggest that UMMD can be used as a promising novel therapeutic strategy to treat colon cancer.

Human Phosphatidylethanolamine-Binding Protein 4 Promoted the Radioresistance of Human Rectal Cancer by Activating Akt in an ROS-Dependent Way

Human phosphatidylethanolamine-binding protein 4(hPEBP4) is a novel anti-apoptosis molecule associated with the resistance of tumors to apoptotic agents. Here we sought to investigate the role of hPEBP4 in the radioresistance of rectal cancer. Immunohistochemistry analysis showed hPEBP4 was expressed in 27/33 of rectal cancer specimens, but only in 2/33 of neighboring normal mucosa. Silencing the expression of hPEBP4 with siRNA significantly reduced the clonogenic survival and enhanced the apoptosis of rectal cancer cells on irradiation. Instead, forced overexpression of hPEBP4 promoted its survival and decreased the apoptosis. Western blot showed hPEBP4 could increase the radiation-induced Akt activation, for which reactive oxygen specimen(ROS) was required. The radioresistance effect of hPEBP4 was reversed after given LY-294002 to inhibit Akt activation or antioxidant to abolish the ROS production. We also confirmed that effect of hPEBP4 in vivo with nude mice. Thus we concluded that hPEBP4, specifically expressed in rectal cancer cells, is associated with radioresistance of rectal cancer, implying that modulation of hPEBP4 may have important therapeutic implications in radiotherapy of rectal cancer.

An experimental research into endostatin microbubble combined with focused ultrasound for anti-tumor angiogenesis in colon cancer

Objective: to evaluate the therapeutic effect of targeted endostatin-loaded microbubbles, combined with improved, focused, directional ultrasound radiation for inhibition of subcutaneous translocation in situ colon tumor angiogenesis in colon cancer. Methods: 65 BALB/c nude mice with subcutaneous translocation in situ colon tumors were randomly divided into five groups. Group A was the control group, without any treatments. In Group B, the mouse was treated with ultrasonic radiation. In Group C, the mouse was treated with ultrasonic radiation combined with empty SonoVue microbubbles. In Group D, the mouse was treated with ultrasonic radiation combined with empty Targestar-SA microbubbles. In Group E, the mouse was treated with ultrasonic radiation combined with endostatin microbubbles. The tumor size was measured before and 1, 14, and 28 days after irradiation. The peak intensity (PI), regional blood volume (RBV) and regional blood flow (RBF) were recorded using contrast-enhanced ultrasound. The tumor tissue was removed for pathological examination; the tumor necrosis area and microvascular density (MVD) were evaluated by immunohistochemistry. Results: Tumors in Groups C, D and E were significantly smaller than in Groups A and B at 28 days after irradiation, with Group E the smallest. PI, RBF and RBV of Groups C, D, and E were significantly decreased 28 days after radiation with Group E the lowest, and significantly lower than Groups A and B (all P < 0.05). The tumor tissue necrosis area of Group E was clearly greater while MVD was obviously lower than the other groups (all P < 0.01) at 28 days after treatment. Conclusion: The targeted endostatin microbubbles, combined with focused, directional ultrasound radiation can damage tumor microvasculature of subcutaneous colon translocation in situ colon cancer, as well as inhibit the tumor angiogenesis.

Primary gastric cancer presenting with a metastatic embolus in the common carotid artery: a case report

Although about 30% of gastric cancers have distant metastasis at the time of initial diagnosis, metastatic tumor embolus in the main blood vessels is not common, especially in the main artery. The report presents, for the first time, an extremely rare clinical case of a metastatic embolus in the common carotid artery (CCA) from primary gastric cancer. Metastatic embolus from the primary tumor should be considered when patients present with gastric cancer accompanied by intravascular emboli. The patient should be actively examined further so as to allow early detection and treatment.

The clinical characteristics of patients with chronic idiopathic anal pain

Abstract The aim of this study was to investigate the clinical characteristics, treatment outcomes and psychological distress in patients with chronic idiopathic anal pain. The study was conducted on patients referred to Hangzhou Third Hospital for chronic anal pain from January, 2010 to December, 2014. Patient demographics, clinical history, anorectal physiology, and radiological imaging data were recorded for all patients. The treatment outcome was noted for patients treated and followed up for more than 6 month at the present unit. Ninety-six patients with mean age of 45.1 years (range, 17-82) were studied. Seventy-one patients (74.0%) had functional anorectal pain(FARP). The main complaints were dull, sharp, stabbing, or spasm pain. Among all patients, 34.3% reported that their pain radiated into other locations. Fifty-one patients (53.1%) had bowel dysfunction, while 28.1% patients had urinary dysfunction. The common factors associated with pain relief were day time, lying down and warm water baths; the factors that contributed to aggravated pain were night time, defecation or sitting. 92.7% (89/96) of patients reported symptoms of psychological disturbance. FARP patients exhibited increased depression than non-FARP patients(P<0.05). In addition, female patients were more likely to have depression than male patients (P<0.05). The overall pain treatment success rate was 55.2% (53/96). The pain treatment outcome was better in non-FARP patients than in FARP patients(χ2=3.85, P<0.05). Conclusively, chronic idiopathic anal pain is a complex clinical symptom, involving pelvic floor muscles, the nervous system, endocrine system, and the patients’ psychological conditions. Further research is needed to improve diagnosis and treatment for patients with chronic idiopathic anal pain.

Effect of a chemical inhibitor of human phosphatidylethanolamine-binding protein 4 on radiosensitivity of rectal cancer cells

BackgroundHuman phosphatidylethanolamine-binding protein 4 (hPEBP4) is a well-established antiapoptosis molecule in recent years. It has also been demonstrated to be involved in the radioresistance of rectal cancer. The objective of this study was to determine whether IOI-42, a chemical inhibitor of hPEBP4, could sensitize rectal cancer cells.MethodsRectal cancer cells were treated with IOI-42 alone or in combination with irradiation. Clonogenic survival assays and tumor volume growth analysis were used, respectively, to study the effect of IOI-42 in vitro and in vivo. Western blot was adopted to measure the activation of signal pathway.ResultsClonogenic survival assays showed that IOI-42, combined with irradiation, caused a significant decrease in colony formation compared with radiation alone, which was associated with the downregulation of Akt activation. And we also confirmed the effect of IOI-42 in nude mice transplanted with human rectal cancer subcutaneously.ConclusionsThese data suggest that IOI-42 has a potential to enhance the radiosensitivity of rectal cancer cells, providing a rationale to further investigate the feasibility of combining of IOI-42 with radiation, keeping in mind that this may result in unexpected toxicities.