Background: Colorectal cancer (CRC) is one of the leading causes of cancer-related death in China. Dysregulation of microRNAs (miRNAs) is involved in cancer development and progression. Our previous study showed an inverse relationship between miR-193a-3p expression and the prognosis of CRC. However, the exact biological functions of miR-193a-3p in CRC are still poorly understood. This study aimed to explore the role and mechanism of miR-193a-3p in CRC. Methods: Real-time PCR and Western blotting were used to examine the expression levels of RNA and protein, respectively. A dual luciferase assay was performed to validate predicted targets of miR-193a-3p. Loss and gain-of-function studies were carried out to reveal the effects and potential mechanism of the miR-193a-3p in the proliferation, metastasis and angiogenesis of CRC cells. Results: The expression levels of miR-193a-3p in human CRC cell lines were significantly decreased compared with that in normal colonic epithelium cell line. Furthermore, plasminogen activator urokinase (PLAU) was validated as a direct target gene of miR-193a-3p. Over-expression of miR-193a-3p inhibited proliferation, migration and angiogenesis of HT-29 cell, whereas forced expression of PLAU could rescue the inhibitory effects. Conclusion: miR-193a-3p might inhibit CRC cell growth, migration and angiogenesis partly through targeting PLAU. MiR-193a-3p/PLAU axis might provide a potent therapeutic opportunity for aggressive CRC.

Thrombocytosis had been found to be associated with tumor metastasis and poor prognosis in malignant tumors including colorectal cancer (CRC). In the present study, we investigated the relationship between the platelet and the biological features in patients with CRC in China. The correlation of platelet counts of 150 cases with CRC with their clinicopathological characteristics was explored. Furthermore, the survival impact of preoperative platelet count was also investigated. Statistically significant correlations between the platelet count and the lymph node and distance metastasis (p=0.016 and 0.014), vascular and perinural invasion (p=0.025 and 0.016) as well as TNM clinical stages (p=0.014) except for the age, gender and grades (p=0.245, 0.276 and 0.324, respectively) were found. In addition, 5-year survival of patients with high platelet count and normal platelet count were 13.30% and 56.30%, respectively (p=0.000). Meanwhile, concurrent with lymph node and distance metastasis, perinural invasion and clinical stages (p=0.000, 0.022, 0.034 and 0.000), platelet count (p=0.010) was also found to be an independent prognostic factor in CRC in our study through multivariate analysis. Elevated platelet might play some role in the progress of CRC and preoperative platelet count might be a prognostic indicator in the CRC patients.

Although aberrations of peroxisome proliferator-activated receptor γ (PPARγ) and phosphatase and tensin homolog (PTEN) expression have been identified in several other cancer types, certain previous studies have revealed that PPARγ is abundant in normal and malignant tissue in the colon. The question of whether aberrant PTEN is involved in the initial stage or is a later event during colorectal carcinogenesis remains controversial. Relatively few studies have focused on the correlation of expression of PPARγ and PTEN in various tissues. In the present study, paraffin-embedded blocks from 139 patients with CRC, 18 adenomatous polyps and 50 paired paracancerous benign mucosas were selected and analysed in 4 tissue microarray (TMA) blocks comprising 104, 72, 130 and 54 cores, respectively. Expression of PPARγ and PTEN was examined using immunohistochemical staining on TMAs. There were no significant differences in the expression of PPARγ (P=0.055) and PTEN (P=0.100) between the colorectal cancers, adenomas and paracancerous mucosas. However, correlations of PPARγ expression with clinical stage (P=0.004) and PTEN expression with histological grade (P=0.006) and distant metastasis (P=0.015) were demonstrated in the CRC specimens. Although the differences in PPARγ and PTEN protein expression in human colorectal cancer may not be considered as early diagnostic markers, our results indicate that CRCs with a low expression or deletion of PTEN may progress towards invasion and even metastasis; thus, PTEN may have potential as a prognostic marker in human CRC.

Elevated levels of C-reactive protein (CRP) have been described as a prognostic factor in various types of human malignancy. In the present study, the prognostic potency of CRP was validated for patients with colorectal cancer (CRC) in order to guide patient management and define high-risk populations for follow-up or for therapeutic purposes. The association between the high sensitivity-CRP (hs-CRP) levels of a total of 123 patients with CRC and their clinicopathological characteristics was explored. Subsequently, univariate and multivariate analyses were performed to investigate the survival impact of pre-treatment hs-CRP levels in this cohort study. Statistically significant correlations between the serum levels of hs-CRP and lymph node and distant metastasis (P5.0 mg/l) hs-CRP levels was demonstrated to be significantly less than that of those in the normal group (≥5.0 mg/l) by applying the Kaplan-Meier method (13.3 versus 57.0%, log-rank test P<0.001). Furthermore, following identification as a prognostic factor through using univariate analysis, high levels of hs-CRP (P<0.001) were validated as an independent prognosticator in CRC in the present study through using multivariate analysis. Pre-treatment serum CRP levels were associated with advanced and progressed CRC patients, therefore these levels may serve as a potential prognostic marker for CRC patients.

Multiple myeloma (MM) is an uncommon type of malignant hematological neoplasm which, besides primarily involving the bone marrow, has a potent tendency to involve other organs and to present with various clinical manifestations. Involvement of the gastrointestinal (GI) system, particularly presenting with GI hemorrhage, in the course of MM is extremely rare. In the present study, we report a case of a middle‑aged male who initially demonstrated GI bleeding and was finally diagnosed with MM. Further laboratory examinations, including analysis of globulin in the blood, bone marrow aspiration and radiogram, supported this diagnosis. This case may promote the possible involvement of plasma cell myeloma in the differential diagnosis of patients with unexplained and refractory GI bleeding. In this study we also present a thorough review of the literature with regard to the association between MM and GI hemorrhage.

The cellular basis for rectal cancer development is still unclear. The aim of this study was to evaluate the relationship between the expression of p53, cyclinD1, bcl-2, ß-catenin, c-myc, cyclooxygenase-2 (COX-2) and nm23-H1 and the clinicopathological characteristics of rectal cancer. Expressions of p53, cyclinD1, bcl-2, ß-catenin, c-myc, COX-2 and nm23-H1 proteins were detected by immunohistochemical staining to two tissue microarrays containing tissues accumulated from 54 human rectal cancers and 40 para-cancer mucosa. Significant differences were demonstrated between the rectal cancers and their benign para-cancer counterparts according to the expressions of p53, cyclinD1, bcl-2, ß-catenin, c-myc, COX-2 and nm23-H1 (p<0.05). Additionally, positive correlations of ß-catenin with cyclinD1 and c-myc (r=0.412, p=0.002; r=0.447, p=0.000) and of p53 with bcl-2 (r=0.332, p=0.001) were found. Cancer tissues with overexpression of ß-catenin or bcl-2 were less likely to differentiate to advanced grade. Expression of cyclinD1 had a correlation with clinical stages (p=0.039). In addition, a negative correlation was found between nm23-H1 expression and the histological grades, distance metastasis and Duke's stages. Aberrant expression of p53, cyclinD1, bcl-2, ß-catenin, c-myc, COX-2 and nm23-H1 might attribute to the carcinogenesis of human rectal cancer. Furthermore, cyclinD1 and nm23-H1 might be involved in rectal cancer progression. This study recommends the application of tissue microarrays in rectal cancer research for its reliable quick throughput.