HGF/NK4, a four-kringle antagonist of hepatocyte growth factor, is an angiogenesis inhibitor that suppresses tumor growth and metastasis in mice

We reported that NK4, composed of the N-terminal hairpin and subsequent four kringle domains of hepatocyte growth factor (HGF), acts as the competitive antagonist for HGF. We now provide the first evidence that NK4 inhibits tumor growth and metastasis as an angiogenesis inhibitor as well as an HGF antagonist. Administration of NK4 suppressed primary tumor growth and lung metastasis of Lewis lung carcinoma and Jyg-MC(A) mammary carcinoma s.c. implanted into mice, although neither HGF nor NK4 affected proliferation and survival of these tumor cells in vitro. NK4 treatment resulted in a remarkable decrease in microvessel density and an increase of apoptotic tumor cells in primary tumors, which suggests that the inhibition of primary tumor growth by NK4 may be achieved by suppression of tumor angiogenesis. In vivo, NK4 inhibited angiogenesis in chick chorioallantoic membranes and in rabbit corneal neovascularization induced by basic fibroblast growth factor (bFGF). In vitro, NK4 inhibited growth and migration of human microvascular endothelial cells induced by bFGF and vascular endothelial growth factor (VEGF) as well as by HGF. HGF and VEGF activated the Met/HGF receptor and the KDR/VEGF receptor, respectively, whereas NK4 inhibited HGF-induced Met tyrosine phosphorylation but not VEGF-induced KDR phosphorylation. NK4 inhibited HGF-induced ERK1/2 (p44/42 mitogen-activated protein kinase) activation, but allowed for bFGF- and VEGF-induced ERK1/2 activation. These results indicate that NK4 is an angiogenesis inhibitor as well as an HGF antagonist, and that the antiangiogenic action of NK4 is independent of its activity as HGF antagonist. The bifunctional properties of NK4 to act as an angiogenesis inhibitor and as an HGF antagonist raises the possibility that NK4 may prove therapeutic for cancer patients.     

T4 Endonuclease Involved in Repair of DNA

An enzyme activity, named T4 endonuclease V, was purified from T4-infected Escherichia coli. The enzyme induces single-stranded breaks in ultraviolet-irradiated DNA but does not act on native or heat-denatured DNA. The enzyme activity is dependent on the dose of ultraviolet irradiation, and the number of the breaks formed is approximately equal to the number of pyrimidine dimers present in the DNA. Denatured DNA, which has been exposed to ultraviolet light, is also attacked by the enzyme although the extent of the reaction is greater with irradiated native DNA. The enzyme shows optimal activity at pH 7.5 and does not require added divalent ions. When the enzyme-treated, irradiated DNA is subjected to stepwise degradation by spleen phosphodiesterase, dimers are released more rapidly than thymine into the acid-soluble fraction, suggesting that the enzyme induces a break at the 5'-side of a pyrimidine dimer. The enzyme, whose formation is controlled by the v(+) gene of T4, appears to be responsible for the first step of excision repair.     

Polygraphic study on the clinical seizures induced during nocturnal sleep.

The subjects of this study consisted of 17 epileptic patients with clinical seizures during all-night sleep recording (the seizure group) and another 17 epileptic patients without clinical seizures (the control group). The results obtained were as follows: 1) The 50-90% out of total clinical seizures were induced in non-REM sleep, while a few clinical seizures were induced in REM sleep. The number of clinical seizures in sleep stage of higher activity level increased as the incidence of clinical seizure during all-night grew. 2) In the seizure group REM sleep could not be detectable during all-night in five cases out of 17 cases, while we could not find cases lacking REM sleep in the control group. This difference between two subject groups was statistically significant (P less than 0.025). 3) As to focal spike group, the spike discharge incidence of total sleeping time and of each sleep stage was higher respectively in the seizure group than that in the control group, and particularly in St.1, St.2 and REM sleep the figure of the discharge incidence was found significantly higher in the seizure group than that in the control group (P less than 0.05). We discussed on above-mentioned results, and we emphasized particularly that REM-sleep suppresses clinical seizures, although non-REM sleep induces clinical seizures.     

Levels of angiogenesis and expression of angiogenesis-related genes are prognostic for organ-specific metastasis of renal cell carcinoma

BACKGROUND: To identify organ-specific, metastasis-related factors that can be used to predict the development and location of metastasis of clear cell renal cell carcinoma (CRCC), the authors assessed the angiogenesis and the expression of angiogenesis-related genes in primary and metastatic tumors. METHODS: They evaluated intratumoral microvessel density (MVD) by immunohistochemical staining, assessed the expression of angiogenesis-related genes by mRNA in situ hybridization, and determined the clinicopathologic characteristics of 92 archival specimens of primary and metastatic CRCCs from 54 patients. All 38 metastatic tumor specimens were resected from 24 patients. RESULTS: The pathologic stage (P=0.026) of the primary tumor specimen was an important predictor for metastasis, as were MVD (P=0.000025) and the ratio of matrix metalloproteinases (MMPs) to E-cadherin (M/E ratio; P=0.000041). In addition, primary tumor specimens resected from patients with metastatic CRCCs had high MVD, high levels of MMP-2 expression, and a high M/E ratio (P <0.05). Relative to the primary tumors, the metastatic tumors also had high MVD, overexpression of basic fibroblast growth factor, vascular endothelial growth factor, interleukin-8, MMPs, and a high M/E ratio (P <0.05). Multivariate analysis revealed that MVD and the M/E ratio in the primary tumor were independent prognostic factors for metastasis (P=0.049 and P=0.001, respectively). Furthermore, the M/E ratio in metastatic tumor specimens resected from the lung and lymph node was an independent prognostic factor for metastasis (P=0.01823 and P=0.03950, respectively). CONCLUSIONS: The current study indicated that angiogenesis and M/E ratio were specific predictors for metastases of RCC, especially to the lung or lymph node. Therefore, MMPs and E-cadherin could be relevant targets for novel therapeutic strategies to control or prevent the metastasis of RCC.     

Diagnostic Peritoneal Lavage for Diagnosing Blunt Hollow Visceral Injury: The Accuracy of Two Different Criteria and Their Combination

Purpose To test the usefulness of diagnostic peritoneal lavage (DPL) for identifying blunt hollow visceral injury with two different sets of criteria or a combination of the two. Methods Fifty victims with physical examinations and/or computed tomography findings equivocal for blunt hollow visceral injury underwent DPL. Whether or not to perform surgery was determined based on Otomo's DPL criteria [lavage white blood cell counts (L-WBC) over lavage red blood cell counts (L-RBC) divided by 150 (L-WBC ≥ L-RBC/150) in the presence of hemoperitoneum, or L-WBC over 500/mm³ (L-WBC ≥ 500) in the absence of hemoperitoneum]. The cell count ratio, a comparison of L-WBC, L-RBC, peripheral WBC (P-WBC), and peripheral RBC (P-RBC) [(L-WBC/L-RBC)/(P-WBC/P-RBC) ≥ 1] were all calculated retrospectively. Results There were one and two false-positive cases based on Otomo's criteria and the cell count ratio, respectively, with corresponding accuracies of 97.8% and 95.7%, respectively. There were no false-positive or -negative cases according to the combined use of Otomo's criteria and cell count ratio, yielding an accuracy of 100%. Conclusion Although each criterion alone is very accurate in predicting the presence of blunt hollow visceral injury, the combined use of the two would further improve the accuracy of the diagnosis and thereby reduce the number of unnecessary celiotomies.