The host immune system normally functions to destroy neoplastic cells that continually develop as a result of somatic mutations. However, patients with head and neck squamous cell carcinoma have depressed cell-mediated immune function, which has recently been shown to be most pronounced in the local and regional environment of the primary tumor. Recent studies suggest a local modulation of the host immune response to tumor by secreted immunoregulatory factors such as cytokines, especially pro-inflammatory cytokines(interleukin-1, interleukin-6, interleukin-8, interferons, and tumor necrosis factor).

To assessthe ability of head and neck squamous cell carcinoma to produce these cytokines, initially, we have performed immunohistochemical staing for interleukin-6 and tumor necrosis factor in 20 cases of laryngeal squamous cell carcinoma and 10 cases of laryngeal nodule as a control group.

We detected interleukin-6 in 11 cases of laryngeal squamous cell carcinoma(55%) and tumor necrosis factor in 11 cases of laryngeal squamous cell carcinoma(55%). All of 10 papillomas showed no expression of interleukin-6 and tumor necrosis factor. There is no statistical correlation between interleukin-6 and tumor necrosis factor expression and clinical stage or pathologic grade.

These results suggest that laryngeal squamous cell carcinoma may secrete cytokines influencing the response of local immune cells. But future studies of the role of tumorderived cytokines in the local immune response to tumor could be investigated,since cytokines may directly or indirectly regulate tumor growth and metastasis.

Phospholipase C isozymes(PLCs) paly a central role in ligand-mediated signal transduction for cellular activity such as proliferation and differentiation. However, the biolog-ical significance of their molecules in carcinogenesis or tumor progression is not determined precisely yet.

Usnig PLC-γ1 specific antibody, we have examined the relative contents of PLC-γ1 in various types of human cancer tissue, by immunoblotting and imm-unohistochemistry techniques. Several oncogene studies and DNA ploidy sutdy were per-formed additionally insome tumors.

Most malignancy showed elevated contentesof PLC-γ1, especially in colorectal and breast cancer, whereas hepatocellular carcinoma revealed decreased expression pf PLC-γ1. onco-protein expression was correlated with PLC-γ1 expression in some tumors. In hepatocellular carcinoma, DNA ploidy has an influenc to PLC-γ1 expression in most of the cases.

In conclusion, alteration or imbalance of the PLC-γ1 mediated signal trans-duction may have a significant role in the devlelopment or progression of cancer. These findings not only have important implications for increasing our understanding of multistage car-cinogenesis but they also have an impact on strategies for diagnosis and theraly of cancers.

This study was aimed to assess the value of rapid urease test (CLO test) for thedetection of Helicobacter (H.) pylori in patiens with duodenal ulcer and compare its resultwith histological technique using H & E stain.

The CLO test and histological study were done using three pieces of antral biopsyspecimens in 46 patients with duodenal ulcer. The clinical histories such as smoking, bloodtype or the previous use of NSAIDs were obtained from the patients.

1) The CLO test was positive in 35 (76.1%) among 46 patients with duodenal ulcer, while H & E stain was positive in 91.3%.

2) When H & E stain positive case was diagnosed as H. pylori infection, the sensitivity of CLO test was 81.0%, the specificitry 75.0% and the predictability was 97.1%.

3) The grading of gastric inflammation showed that the higher the histologogical grade, the more likely CLO test would be positive.

4) There were no differences of recurring history of duodenal ulcer, smoking rate, NSAIDs history and blood type between 34 cases of both CLO and H & E positive cases and 3 cases ofboth negative cases except a mild increasing tendency of age, male predominance and scarringstage of duodenal ulcer in both negative cases.

The CLO test is a rapid and simple test, but it should require other complementary diagnostic tests to increase the sensitivity and specificity.