Matrix metalloproteinase-7 (MMP-7) secreted by cancer cells has been implicated classically in the basement membrane destruction associated with tumor cell invasion and metastasis. Recent epidemiologic studies have established a correlation between high levels of circulating insulinlike growth factor (IGF) and low levels of IGF binding protein 3 (IGFBP-3), and relative risk of developing colon, breast, prostate, and lung cancer, which are known to produce MMP-7. In this study, IGFBP-3 was assessed as a candidate for the physiologic substrate of MMP-7. MMP-7 proteolysis generated four major fragments (26 kDa, 17 kDa, 15.5 kDa, and 15.

Advanced prostate cancer frequently involves the bone that has the largest content of insulin-like growth factors (IGFs). However, the role of bone-derived IGFs in bone metastasis of prostate cancer has not been studied extensively because of the lack of a reliable animal model. Therefore, we investigated whether a novel antibody directed against human IGF-I and IGF-II (KM1468) could inhibit the development of new bone tumors and the progression of established bone tumors in nonobese diabetic/severe combined immunodeficient mice implanted with human adult bone. We first confirmed that KM1468 bound specifically to human IGF-I, human IGF-II, and mouse IGF-II but not to insulin. It also blocked autophosphorylation of the type I IGF receptor induced by the binding of IGFs in human-type I IGF receptor-overexpressing BALB/c 3T3 cells, and it inhibited the IGF-stimulated growth of MDA PCa 2b cells in vitro. Then mice were injected intraperitoneally with KM1468 once weekly for 4 weeks either immediately or 4 weeks after inoculation of MDA PCa 2b cells. KM1468 markedly and dose-dependently suppressed the development of new bone tumors and the progression of established tumor foci, as determined by histomorphometry, and it also decreased serum prostatespecific antigen levels, compared with the control. This is the first report of an IGF ligand-specific inhibitory antibody that suppresses the growth of human prostate cancer cells in human adult bone. These results indicate that the IGF signaling axis is a potential target for prevention and treatment of bone metastases arising from prostate cancer.

Aim : To clarify the influence of hypertension on lower urinary tract symptoms (LUTS) we examined the relationship between blood pressure, LUTS, and the effect of terazosin on LUTS in patients with benign prostatic hyperplasia (BPH). Methods : The subjects were patients who had LUTS and BPH. They were treated with terazosin (1 mg, twice-a-day) for 12 weeks. Calculation of the International Prostate Symptom Score (IPSS), measurement of blood pressure, and uroflowmetry were performed before and after 12 weeks of therapy. Patients were divided into a normotensive (NT) group and a hypertensive (HT) group at the time of first examination. Results : The IPSS for urinary frequency and nocturia in BPH-HT patients ( n = 21; mean age, 71 years) were significantly higher than those in the BPH-NT patients ( n = 21; mean age, 69 years) before the administration of terazosin. The total IPSS the BPH-HT patients was also significantly higher than that of the BPH-NT patients. There were no differences of uroflowmetric parameters between the two groups. After 12 weeks of therapy, systolic and diastolic blood pressure decreased in the BPH-HT patients, but not in the BPH-NT patients. However, the systolic pressure of the BPH-HT patients was still significantly higher than that of the BPH-NT patients. The score for each IPSS parameter decreased in both groups, but the difference of the score between the two groups increased. Conclusion : Hypertension may worsen LUTS and may decrease the improvement of symptoms by terazosin.

Environmental stimuli, such as organ-specific growth factors, can influence the metastatic potential of a tumor. The liver is the main source of insulin-like growth factors (IGFs). The importance of IGF signal in hepatic metastasis has been clarified mainly by IGF-I receptor targeting strategies. This study aims to confirm these precedent reports by novel tool, neutralizing antibodies against IGFs and to show that IGFs are promising therapeutic targets for hepatic metastasis in vivo. Hepatic metastasis was induced by intrasplenic injection of human colorectal cancer cell line, HT29. The antimetastatic effects of three antibodies (anti-mouse IGF-I, anti-mouse IGF-II, and anti-human/mouse IGF-II designated KM1468) were tested singly or in combination in the early phase of metastasis. The dose escalation effect of KM1468 and its survival benefit were examined in the early and late phases of metastasis. The mechanism of IGF neutralization was investigated with immunohistochemistry. Dual neutralization of paracrine IGF-I and IGF-II showed modest additive antimetastatic effects than single neutralization of IGF-I or IGF-II. In any phase of metastasis, neutralization led to significant tumor growth inhibition and longer survival. Dose escalation of KM1468 influenced survival only in the late phase of metastasis. Apoptosis increased significantly in the antibody-treated group compared with the control group (P = 0.0025) In conclusion, IGFs are promising therapeutic targets for hepatic metastases of colorectal cancers. However, the IGF dependency is probably variable in the metastatic process.Almost one-third of patients dying from colorectal cancer have metastatic tumors only in the liver. The control of hepatic metastasis leads directly to an improvement in the overall cure rate for colorectal cancer (1). However, our lack of understanding of the molecular mechanisms mediating the process of hepatic metastasis means that few theoretical treatments for this syndrome have yet been developed.The insulin-like growth factors (IGFs) have been widely investigated for a possible role in promoting the oncogenic transformation, growth, and survival of cancer cells (2 -6). They are expressed ubiquitously and act as endocrine, paracrine, and autocrine growth factors. In most tissues, they are synthesized together with six molecular species of specific binding proteins (IGFBP-1 to IGFBP-6), which modulate IGF action in the cell environment, generally by inhibiting it. Limited proteolysis of IGFBPs is an essential mechanism in the regulation of IGF bioavailability both in the bloodstream and at the cellular level (7,8). The liver is the main source of IGFs, and there are reports demonstrating the importance of IGF signals in hepatic metastasis formation (9 -13). We speculated in a previous report that free/bioactive IGFs generated from IGFBP-3 proteolysis by matrix metalloproteinase-7 play a crucial role in hepatic metastasis in human colorectal cancers (14).Recently, this IGF system has been recognized as a potent therapeu...