Matrix metalloproteinases (MMPs) are known to play important roles in extracellular matrix remodeling during the process of tumor invasion and metastasis. However, little is known about their role in esophageal squamous cell carcinoma (ESCC). Expression of MMP-2 and MMP-9 in ESCC was detected in our research. Tissue microarray chip was prepared, consisting of 58 cases of ESCC and corresponding esophageal epithelium tissues. MMP-2 and MMP-9 were examined by immunohistochemistry. Overexpression of MMP-2 and MMP-9 was found in ESCC (42.1 and 60.3%, respectively), compared with paired distal normal esophageal tissues (22.9 and 8.9%, respectively). Expression of MMP-2 in ESCC was significantly associated with the tumor invasion depth, tumor-node-metastasis stages, and lymph node metastasis. MMP-2 and MMP-9 may play important roles in carcinogenesis, and MMP-2 may act as a biological marker of invasion and lymph node metastasis in ESCC.

In vitro, some EPIs can strengthen the activities of different antibiotics which are the putative substrates of the efflux pump system in H. pylori.

Human colorectal carcinoma (CRC) is one of the leading cancers. Every year, the WHO estimates a total of 945,000 new CRC cases, with 492,000 deaths worldwide. Most CRCs arise from the main premalignant lesion, colorectal adenomas, and the progression of colorectal adenoma to CRCs may take a long-term time course. The development of human CRCs is not only determined by the adenomatous cells, but also by the interaction between adenomatous cells and host immune environment. In response to tumor initiation or invasion, many inflammatory cells and components will be inevitably activated and form an inflammatory microenvironment surrounding the CRC tumors. Accumulative evidence has revealed that inflammatory response plays a key role in the development of human CRCs by implicating in many aspects including in determining the microenvironmental immune function shift from immunosurveillance to immunosuppression and significantly influences the progression of precancerous lesions to cancers. In this review, the functional changes of immune microenvironment from precancerous stage (adenoma) to cancer stage are summarized, and their potential as predictive biomarkers and biotherapeutic significance in preventing the development of CRCs are discussed.

No abstract

Immunosuppressive factors derived from the tumor and nontumor cells present in the tumor microenvironment contribute to tumor escape from host immune attack. Recently, the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO) derived from both the tumor cells and surrounding nontumor cells was found to function as a critical immunosuppressive factor. While the expression of IDO is intensively under investigation in many types of cancers, little information is available in esophageal squamous cell carcinomas (ESCC) thus far. In this study, we have therefore investigated the cellular localization of IDO in 45 ESSCs and ten morphologically normal esophageal tissues; the correlation of IDO with clinicopathological parameters was also analyzed. Immunohistochemistry (IHC) analysis revealed that the density of IDO-positive cells was increased in ESCCs relative to controls (P < 0.01). These cells were distributed as clusters and formed a patchy pattern in both the cancerous epithelium and the surrounding noncancerous cells. Double IHC further confirmed that many IDO-positive cells in the tumor stroma were smooth-muscle-actin-alpha-positive myofibroblasts, CD68-positive macrophages, and S100-positive dendritic cells. Statistical analysis showed that the densities of IDO-positive cells were not significantly correlated with tumor clinical parameters (tumor invasion depth, node metastasis, and TNM stages) and lymphocytic infiltration. Our current findings suggested that the increased IDO expression in ESCCs is from a mixed cellular source (both cancer cells and noncancerous cells). Further studies on immune cell functional analysis are required in the future.