It has been confirmed that several genes are involved in each step of liver metastasis of colorectal cancer. This article reviews recent highlights in this field. The expression of c-erbB2 or Rho protein in colorectal cancer tissues correlates closely with liver metastasis. Suppressor genes such as nm23, DCC, and DPC4 may play a role in the suppression of liver metastasis. On the other hand, the E-cadherin-catenin system, carbohydrate chains, selectin, and variant CD44 are known to play an important role in cells migration from the primary lesion, the adhesion of tumor cells to endothelial cells, and cell motility. These adhesion molecules may be a biological marker of liver metastasis. In addition, treatment targeting these genes will be a potent therapy for liver metastasis in the future.

By keeping a cytomorphological basis for the diagnosis of leukemia according to the FAB classification, a new classification system was proposed by the WHO group, which incorporated four genetically established entities of acute leukemia. This classification also made some changes in MDS categories and provided new criteria for diagnosing acute myeloid leukemia. Combined use of this classification with the FAB classification will promote investigations into leukemia.

The recent advances in molecular biology and gene engineering have greatly contributed to the diagnosis and treatment of hematopoietic malignancies, such as leukemia and malignant lymphoma. It is now possible to precisely determine the clonal origin of malignant cells, the subtype of leukemia or lymphoma, and the clinical prognosis in each patient. Furthermore, minimal residual malignant cells in leukemia or lymphoma patients after achieving complete remission can be detected by DNA analysis. Based on these analyses, theoretically treatment can be tailored for each patient. We discuss in the present paper the usefulness of DNA or gene analyses in the clinical laboratory for hematopoietic malignancies.

We describe here the clinical applications of fluorescence in situ hybridization(FISH) in patients with chronic myelogenous leukemia under treatment with interferon-alpha, some cases with a false positive caused by preparation of specimen and/or probes, and the detection of chimerism after sex-mismatched bone marrow transplantation based on our clinical experience. Furthermore, we introduced our methods of performing FISH using blood smear or G banding specimens.

Tyrosine kinase inhibitors have drawn the most attention in recent years as molecular target agents for cancer treatment. The reason for this can only be the dramatic antitumor effects shown in early clinical trials against small cell cancer and chronic myeloid leukemia by the EGFR tyrosine kinase inhibitor, ZD1839, and the BCR-Abl tyrosine kinase inhibitor, STI-571, respectively. Various hypotheses were advanced in the preliminary stages of the clinical development of such molecular target agents: "They only prevent cancer cell proliferation and have no killer cell activity; they are extremely weak, and can not be expected to reduce tumors at the clinical level. "Or:" A long time is required before their physiological activity will be expressed in an antitumor effect." However, with non-small cell lung cancer, the most difficult tumor among solid cancers for an anticancer agent to be effective, not only was ZD1839 effective, but showed clear effectiveness in combination chemotherapy in the pretreatment stage. Moreover, the time for the expression of its tumor reduction effect was virtually the same as with conventional anticancer drugs, and its effectiveness proved to last longer after its initial expression. ZD1839 has succeeded in remaking the very image of molecular target agents for cancer treatment. In what follows, we focus mainly on the EGFR tyrosine kinase inhibitor, ZD1839.

A 35-year-old man with chronic myeloid leukemia (CML) in blastic crisis (BC) received an allogeneic bone marrow transplant from an unrelated donor in October 1998 after three cycles of chemotherapy. BC relapse developed on day 349 after transplantation. After one cycle of chemotherapy and treatment with interferon, the patient received donor lymphocyte infusion (DLI), and this resulted in a complete cytogenetic response 21 days later. Grade III acute graft-versus-host disease developed on day 25 after DLI, but this was resolved after administration of prednisolone. Disease relapse occurred at extramedullary sites on day 162 after DLI, and the patient died of sepsis after receiving chemotherapy. This case illustrates that unrelated DLI can induce remission successfully in patients with relapse of CML in BC through a graft-versus-leukemia effect.

We present one pedigree of familial cerebral cavernous angioma (FCCA). Case 1 was a 52-year-old male with right hemiplegia. When he was 37 years old, a left occipital lesion was excised and histologically diagnosed as cavernous angioma. MR image showed many cavernous angiomas in the right temporal lobe, the right paraventriclar white matter, the right frontal lobe, the left basal ganglia, and the left parietal lobe. Stereotactic radiosurgery was undertaken for all the lesions. Although the size of each lesion was unchanged, neither hemorrhage nor neurological deterioration were recognized after radiosurgery. Case 2 was a 24-year-old male, a son of the patient in case 1. He has manifested tonic-clonic type epilepsy since the age of 2. MR image showed cavernous angiomas in the pons, the right frontal, and the left intra-Sylvian regions, and many paraventricular cysts with rims indication of previous hemorrhages. Two de novo lesions were observed on subsequent annual MR screening. Surgical excision for the left intra-Sylvian lesion and stereotactic radiosurgery for all lesions were undertaken. Histological diagnosis was cavernous angioma. In the literature, there were 17 pedigrees and 37 cases of FCCA in Japan. The incidence of both multiple lesions and hemorrhage were less than in found in Spanish or French cases. Stereotactic radiosurgery is considered an useful treatment for FCCA, because lesions are multiple and de novo lesions occur.

Smoking, alcohol and chronic stimulation of the teeth are acknowledged as determinants of the risk for head and neck squamous cell carcinoma (H&NSCC) through the loss or mutation of tumor suppressor genes. Despite diagnostic and therapeutic advance, the overall prognosis of H&NSCC remains poor except for laryngeal cancer. Although the prognosis of H&NSCC depends primarily on clinicopathological factors (ex. TNM), the predictive value has been limited for the identification of patients with high risk of disease relapse. Recently, the analysis of DNA, oncogen amplification, and protein expression have been used in attempts to identify a new prognostic indicator for the evaluation and selection of optimal cancer treatment. Here, I review the literature on prognostic factors including chromosomes, cell cycle, apoptosis, angiogenesis, cytokines and adhesion molecules for patients with H&NSCC.

Squamous Cell Carcinoma (SCC) is the most frequent malignancy in the oral cavity. p53 protein has been reported to be expressed at high levels in malignant lesions, while the level in premalignant lesions has yet to be determined. In this study, oral leukoplakia and oral SCC were examined. Seventy-four incision or excision samples from 43 cases diagnosed as leukoplakia, and 41 samples from 37 SCC cases in the oral cavity, were obtained. All samples (formalin-fixed, paraffin embedded) were examined immunohistochemically for overexpression of p53 protein with monoclonal antibody BP 53-12. As the result, 1. Twenty-two out of 43 leukoplakia cases, and 29 out of 37 oral SCC cases, were positive for p53 protein. 2. p53 protein was overexpressed in premalignant lesions, especially in the cases with moderate and severe epithelial dysplasia. 3. There was a relation between p53 protein expression and pathological features of leukoplakia (epithelial dysplasia), statistically. 4. There was a relation between p53 protein expression and clinical features of leukoplakia, statistically. 5. Malignant transformation during clinical observation was seen in 11 cases. Nine out of 11 cases were positive for p53 even before malignant transformation. Since in cancer-development cases, p53 staining was detected even before malignant transformation of oral leukoplakia to squamous cell carcinoma, it is indicated that p53 accumulation occurred at a early stage of cancer-development. In conclusion, immunohistochemical analysis of p53 protein is suggested to be useful diagnostic procedure for oral leukoplakia, which may develop into oral SCC.

We examined, immunohistochemically and molecular biologically, p53 gene expression in 10 patients with colonic cancer. RNA was extracted from paraffin embedded normal and colonic cancer tissues by using RNA isolator kit and proteinase K. The most effective time and concentration of proteinase K for RNA extraction was 24 hours and 100 micrograms/ml, respectively. P53 gene expression was analyzed by ABI PRISM 7700 Sequence Detection System(ABI 7700 System, Perkinelmer). Gene expression level in each sample was estimated on the basis of the standard curve of ABI 7700 System. Human G3PDH gene was used as the internal control. Immunohistochemically, the tumor cells in all examined cases showed a strong positivity for anti-p53 gene antibody. In ABI 7700 System, expression of p53 gene in the malignant tissues revealed a high level in only 2 cases that had a clinical stage IV, however, in remaining 8 cases a clinical stage was I to III and expression level of p53 was relatively lower. These results suggest that colonic cancer cells show mutant-p53 gene expression, and a ratio of mutant- to wild-p53 gene may have something to do with a relationship between gene expression and clinical stage.

Molecular diagnostic tests are widely performed in managing hematologic malignancies such as leukemia and lymphoma. In this article, we review the present application and problems of the tests. Karyotyping is performed at diagnosis of all kinds of hematologic malignancies. This method needs dividing cells as samples and skilled experts. Fluorescence in situ hybridization(FISH) analysis using cells in interphase is performed, for example, to monitor the effect of interferon on chronic myelogenous leukemia patients. The weak point of this method is that approximately 2% of false-positive cells are inevitable. Southern blot method is used for clonal analysis in some disease, for example, adult T-cell leukemia/lymphoma. Polymerase chain reaction(PCR) method using genomic DNA is performed for limited types of diseases such as lymphoma with bcl-2/IgH fusion gene. Reverse transcription(RT)-PCR method can detect fusion gene transcripts with high sensitivity. This method is useful for detecting minimal residual diseases after chemotherapy or bone marrow transplantation. To perform quantitative analysis, real-time PCR or competitive PCR must be done. In the near future, new technology such as gene expression profiling analysis using DNA microarrays or spectral karyotyping(SKY) method will be used in clinical practice.