[Relationship of TCM syndrome type of gastric mucosal epithelial growth factor, vascular endothelial growth factor and proliferative cell nuclear antigen in patients with chronic atrophic gastritis].

OBJECTIVE: To study the relationship of TCM syndrome type of gastric mucosal epithelial growth factor (EGF), vascular endothelial growth factor (VEGF) and proliferative cell nuclear antigen (PCNA) in patients with chronic atrophic gastritis (CAG) for exploring the essence of TCM type and providing a theoretical basis of clinical treatment. METHODS: TCM syndrome type of 200 patients with diagnosis of CAG confirmed by fibro-gastroscope and pathological examination were differentially classified, and the expressions of EGF, VEGF and PCNA in different types were determined using immunohistochemistry. RESULTS: Patients were differentiated as Pi-Wei deficiency type (Type I ) in 72; Gan-Wei disharmony type (Type II ) in 43; Pi-deficiency with qi stagnation type (Type III) in 32; Wei-yin deficiency type (Type IV) in 24; Pi-Wei damp-heat type (Type V) in 14; and Wei-collateral stasis obstruction type (Type VI) in 5. The difference of PCNA expression level between Type II with Type I , III and IV was significant (P < 0.05). No significant difference in expression levels of EGF and VEGF was found among the 6 types (P > 0.05). CONCLUSION: Type I and II were the dominant TCM syndrome types in CAG patients; the high expression of PCNA might be a diagnostic evidence for Gan-Wei disharmony syndrome.

The agonist of the protease-activated receptor-1 (PAR) but not PAR3 mimics thrombin-induced vascular endothelial growth factor release in human smooth muscle cells.

Thrombin, a serine protease generated by the activation of the blood coagulation cascade following vessel injury, induces vascular endothelial growth factor-(VEGF) release. However, the molecular mechanism of thrombin-induced VEGF release is largely unknown. Anagonist of protease-activated receptor-i (PARI), SFLL-RNPNDKYEPF, mimicked thrombin-induced VEGF release in human vascular smooth muscle (HVSM) cells, as determined by enzyme-linked immunosorbent assay, reverse transcriptase-polymerase chain reaction, and Northern blotting. In contrast, the agonist of PAR3, TFR- GAP, did not affect VEGF release or expression. SFLL-RNPNDKYEPF, but not TFRGAP, up-regulated [Ca2-]i.Moreover, the calcium ionophone A23187 was found to trigger VEGF release in HVSM cells. Thrombin-inducedVEGF release was blocked by anti-thrombin, heparin, a synthetic thrombin receptor inhibitor E5510, the calcium chelator BAPTA, the protein kinase C inhibitor calphostin C, and the MEK1/2 inhibitor U0126. Thus, our data show that thrombin caused VEGF release via PARI activation in a manner dependent on [Ca2+]i and p44/42 downstream from the receptor activation.

"Vasocrine" formation of tumor cell-lined vascular spaces: implications for rational design of antiangiogenic therapies.

Here we report that B16F10 murine melanoma cells mimic endothelial cell behavior and the angiogenic process in vitro and in vivo. Cord formation in vitro by tumor cells is stimulated by hypoxia and vascular endothelial growth factor (VEGF) and inhibited by antibodies against VEGF and the VEGF KDR receptor (VEGF receptor 2). We define regulation of tumor cell-derived vascular space formation by these vasoactive compounds as "vasocrine" stimulation. ICRF 159 (Razoxane; NSC 129943) prevents tumor cell but not endothelial cell cord formation in vitro, and the antiangiogenic drug TNP-470 (NSC 642492) inhibits endothelial but not tumor cell cord formation in vitro. Both drugs inhibit formation of blood-filled vascular spaces in vivo. These results bear on the anticipated action of ICRF 159 in human clinical trials and novel strategies for targeting tumor blood supplies.

Effect of ascorbate on the activity of hypoxia-inducible factor in cancer cells.

Hypoxia-inducible factor (HIF) plays an important role in determining patterns of gene expression in cancer. HIF is down-regulated in oxygenated cells by a series of Fe (II) and 2-oxoglutarate dependent dioxygenases that hydroxylate specific residues in the regulatory HIF-alpha subunits. Because these enzymes require ascorbate for activity in vitro we analyzed the effects of ascorbate on HIF in human cancer cell lines. Ascorbate at physiological concentrations (25 micro M) strikingly suppressed HIF-1alpha protein levels and HIF transcriptional targets, particularly when the system was oncogenically activated in normoxic cells. Similar results were obtained with iron supplementation. These results indicate that both ascorbate and iron availability have major effects on HIF, and imply that the system is commonly regulated by limiting hydroxylase activity under normoxic tissue culture conditions.

Hyperbaric oxygen treatment prevents up-regulation of angiogenesis following partial-thickness skin grafts in the pig.

We hypothesized that hyperbaric oxygen treatment (HBO) would reduce neovascularization following partial-thickness skin grafting in the Yucatan pig. Results show that capillary density 4 days post-graft is increased twofold in grafts not treated with HBO, compared to normal, ungrafted skin or skin grafts from pigs treated with HBO, p < 0.05. Similarly, the expression of vascular endothelial growth factor, a growth factor associated with neovascularization, was also reduced by HBO. Cell density in the graft boundary increased gradually after grafting, reaching a maximum 2.7-fold increase, relative to normal skin, at day 4, p < 0.05. Cell nuclei positive for proliferating cell nuclear antigen, a marker of proliferation, increased threefold by day 2, p < 0.05, and then declined to normal levels by day 7. HBO had no effect on cell density or proliferation in the boundary region or on shear strength of the graft. In the epidermis, proliferation declined 80% 2 days after grafting and then returned to levels observed in normal skin by day 4, p < 0.05; however, in pigs treated with HBO, we observed no decline in proliferation. These findings confirm the hypothesis that HBO reduces neovascularization in the partial-thickness skin graft while preserving regenerative capacity in the graft boundary and normal proliferative capacity of the epidermis.

Cyclooxygenase-1 is overexpressed and promotes angiogenic growth factor production in ovarian cancer.

Inhibition of cyclooygenase-2 (COX-2) catalytic activity has proven successful in restricting the growth of epithelial-derived cancers in vivo. Whether COX-2 inhibitor therapy would be beneficial in the prevention and/or treatment of ovarian cancer, the most lethal gynecological malignancy worldwide, is not known. Most patients with ovarian cancer undergo cytoreductive therapy. Because many of the cytotoxic drugs used to treat ovarian cancer induce COX-2 expression, samples from patients that had not undergone cytoreductive therapy were specifically chosen for COX isoform expression analysis. A majority of specimens exhibited elevated levels of COX-1, not COX-2, mRNA, and protein compared with normal ovarian tissue. Focal regions within the tumor expressing high COX-1 also had elevated levels of pro-angiogenic proteins. Selective inhibition of COX-1, not COX-2, inhibited arachidonic acid-stimulated vascular endothelial growth factor production, which could be reversed by cotreatment with prostaglandin E(2). Thus, COX-1 may contribute to carcinoma development in the ovary through stimulation of neovascularization. Clinical studies testing the efficacy of COX inhibition as adjuvant therapy for ovarian cancer may see more beneficial effects with adjuvant therapy with either a COX-1 selective or nonselective cyclooxygenase inhibitor as compared with a COX-2 selective drug.

Inhibition of cyclooxygenase-2 by rofecoxib attenuates the growth and metastatic potential of colorectal carcinoma in mice.

A large number of epidemiological studies have shown that regular use of aspirinor other nonsteroidal anti-inflammatory drugs (NSAIDs) results in a 40-50% reduced risk of colorectal cancer (CRC). Furthermore, NSAIDs cause the regression of preexisting adenomas in patients with familial adenomatous polyposis and significantly inhibit tumor growth in animal models of CRC. To establish a CRC liver metastasis model, we implanted mouse colon tumor MC-26 cells into the splenic subcapsule of BALB/c mice, after which mice were given either standard chow or chow containing the cyclooxygenase (COX)-2-specific inhibitor rofecoxib, alone or in combination with the standard antineoplastic agents, 5-fluoruracil or irinotecan. After 14 days, mice that were given rofecoxib or irinotecan, but not 5-fluoruracil, had significantly smaller primary tumors and fewer metastases. Rofecoxib, at clinical anti-inflammatory plasma concentrations, enhanced the effects of both antineoplastic agents when used in combination. Biochemical analyses of the primary splenic tumor in rofecoxib-treated mice showed no alteration in COX-1 expression, but significant decreases in the expression of the tumor-promoting proteins COX-2, cyclin D1, cytosolic beta-catenin, matrix metalloproteinases-2 and -9, and vascular endothelial cell- derived growth factor. Rofecoxib also decreased growth-enhancing prostaglandin E(2) and tumor-suppressive interleukin-10, whereas antineoplastic interleukin-12 was increased. Two separate survival studies were performed. When mice were fed chow containing 0.01% rofecoxib beginning on day 0 after tumor cell implantation, which achieved clinical anti-inflammatory plasma concentrations, survival time was significantly longer compared with mice given control chow. After 30 days, mortality in the control group was 90%, whereas only one mouse (5%) treated with rofecoxib had died after 30 days. In the second survival study, all of the mice were initially fed with regular chow after tumor cell implantation. On day 7, mice were randomly divided into three dietary groups: control chow, low-dose (0.01%) rofecoxib chow, and high-dose (0.025%) rofecoxib chow. After 28 days, mortality was 100%, 20%, and 10% in control, low-, and high-dose rofecoxib fed groups, respectively. These studies demonstrate that rofecoxib decreases the growth and metastatic potential of CRC in mice through multiple mechanisms. These studies in mice also provide important information that supports the benefit of COX-2 inhibition, not only in the prevention of CRC, but also potentially in the treatment of this common malignancy. Clinical trials will be necessary to assess the utility of COX-2 inhibitors as adjuvant therapy for early-stage disease and as potential agents, either alone or in combination, with more established drugs, for the treatment of refractory CRC.

Dermal wound healing properties of redox-active grape seed proanthocyanidins.

Angiogenesis plays a central role in wound healing. Among many known growth factors, vascular endothelial growth factor (VEGF) is believed to be the most prevalent, efficacious, and long-term signal that is known to stimulate angiogenesis in wounds. The wound site is rich in oxidants, such as hydrogen peroxide, mostly contributed by neutrophils and macrophages. We proposed that oxidants in the wound microenvironment support the repair process. Proanthocyanidins or condensed tannins are a group of biologically active polyphenolic bioflavonoids that are synthesized by many plants. Previously we have reported that a grape seed proanthycyanidin extract containing 5000 ppm resveratrol (GSPE) potently upregulates oxidant and tumor necrosis factor-alpha inducible VEGF expression in human keratinocytes (Free Radic. Biol. Med. 31:38-42, 2001). Our current objective was to follow up on that finding and test whether GSPE influences dermal wound healing in vivo. First, using a VEGF promoter-driven luciferase reporter construct we observed that the potentiating effect of GSPE on inducible VEGF expression is at the transcriptional level. The reporter assay showed that GSPE alone is able to drive VEGF transcription. Next, two dermal excisional wounds were inflicted on the back of mice and the wounds were left to heal by secondary intention. Topical application of GSPE accelerated wound contraction and closure. GSPE treatment was associated with a more well-defined hyperproliferative epithelial region, higher cell density, enhanced deposition of connective tissue, and improved histological architecture. GSPE treatment also increased VEGF and tenascin expression in the wound edge tissue. Tissue glutathione oxidation and 4-hydroxynonenal immunostaining results supported that GSPE application enhanced the oxidizing environment at the wound site. Oxidants are known to promote both VEGF as well as tenascin expression. In summary, our current study provides firm evidence to support that topical application of GSPE represents a feasible and productive approach to support dermal wound healing.

Hyperbaric oxygen selectively induces angiopoietin-2 in human umbilical vein endothelial cells.

One of the biological effects of hyperbaric oxygen (HBO) therapy in enhancing ischemia-related wound healing is the induction of angiogenesis. To elucidate the mechanism(s) underlying the HBO-induced angiogenesis, we studied the expression of several angiogenesis-related genes in human umbilical vein endothelial cells exposed to HBO. Western blot analyses showed that HBO enhanced the expression of angiopoietin-2 (Ang2) with no effect on the expression of Tie2, angiopoietin-1, and VEGF. The induction of Ang2 was further confirmed by immunohistochemistry, quantitative PCR, and Northern blot analyses. Inhibition of endothelial nitric oxide synthase blocked the HBO-induced Ang2 expression, but failed to block hypoxia-induced Ang2 expression. These data indicated that HBO-induced Ang2 expression may be through transcriptional stimulation, and requires the nitric oxide signaling pathway, which may play an important role in HBO-induced angiogenesis.

Estrogen regulation of uterine genes in vivo detected by complementary DNA array.

INTRODUCTION: In the present study, our aim was to identify differentially expressed genes involved in estrogen actions at the endometrium level in rats. METHODS: Thirty adult rats were ovariectomized four days prior to drug administration for 48 days. Rats were divided in 2 groups: I, control and II, conjugated equine estrogens (CCE). Total RNA was isolated from uterus, and differential expression was analyzed by array technology and RT-PCR. RESULTS: A total of 32 candidate genes were shown to be upregulated or downregulated in groups I or II. Among them, differential expression was already confirmed by RT-PCR for IGFBP5, S12, c-kit, and VEGF, genes whose expression was up regulated during CCE therapy, and casein kinase II and serine kinase expression was the same level in both groups. CONCLUSION: We have demonstrated that cDNA array represents a powerful approach to identify key molecules in the estrogens therapy. A number of the candidates reported here should provide new markers that may contribute to the detection of target estrogen receptor. This information may also aid the development of new approaches to therapeutic intervention.

Anti-angiogenic action of hyperthermia by suppressing gene expression and production of tumour-derived vascular endothelial growth factor in vivo and in vitro.

Vascular endothelial growth factor is an important angiogenic factor for tumour progression because it increases endothelial-cell proliferation and remodels extracellular matrix in blood vessels. We demonstrated that hyperthermia at 42 degrees C, termed heat shock, suppressed the gene expression and production of vascular endothelial growth factor in human fibrosarcoma HT-1080 cells and inhibited its in vitro angiogenic action on human umbilical vein endothelial cells. The gene expression of alternative splicing variants for vascular endothelial growth factor, VEGF121, VEGF165 and VEGF189, was constitutively detected in HT-1080 cells, but the VEGF189 transcript was less abundant than VEGF121 and VEGF165. When HT-1080 cells were treated with heat shock at 42 degrees C for 4 h and then maintained at 37 degrees C for another 24 h, the gene expression of all vascular endothelial growth factor variants was suppressed. In addition, HT-1080 cells were found to produce abundant VEGF165, but much less VEGF121, both of which were inhibited by heat shock. Furthermore, the level of vascular endothelial growth factor in sera from six cancer patients was significantly diminished 2-3 weeks after completion of whole-body hyperthermia at 42 degrees C (49.9+/-36.5 pg x ml(-1), P<0.01) as compared with that prior to the treatment (177.0+/-77.5 pg x ml(-1)). On the other hand, HT-1080 cell-conditioned medium showed vascular endothelial growth factor-dependent cell proliferative activity and the augmentation of pro-matrix metalloproteinase-1 production in human umbilical vein endothelial cells. The augmentation of endothelial-cell proliferation and pro-matrix metalloproteinase-1 production was poor when human umbilical vein endothelial cells were treated with conditioned medium from heat-shocked HT-1080 cells. These results suggest that hyperthermia acts as an anti-angiogenic strategy by suppressing the expression of tumour-derived vascular endothelial growth factor production and thereby inhibiting endothelial-cell proliferation and extracellular matrix remodelling in blood vessels.

Angiogenesis in bladder cancer--prognostic marker and target for future therapy.

Angiogenesis is the process by which tumours induce a blood supply, crucial for growth and metastasis. Evidence for its role in bladder carcinogenesis, its usefulness as a marker of patient prognosis, and potential anti-angiogenic therapies for future development are discussed in this chapter.

Reactive oxygen species accelerate production of vascular endothelial growth factor by advanced glycation end products in RAW264.7 mouse macrophages.

Advanced glycation end products (AGEs) are believed to play an important role in the development of angiopathy in diabetes mellitus. Previous reports suggested a correlation between accumulation of AGEs and production of vascular endothelial growth factor (VEGF) in human diabetic retina. However, the mechanisms involved were not revealed. In this study, we investigated the transcriptional regulation of the expression of vascular endothelial growth factor (VEGF) by AGEs, and possible involvement of reactive oxygen species (ROS) in the induction. We employed an AGE of bovine serum albumin (BSA) prepared by an incubation of BSA with D-glucose for 40 weeks and N(epsilon)-(carboxymethyl)lysine (CML), a major AGE. The expression of VEGF was induced by CML-BSA in RAW264.7 mouse macrophage-like cells. CML-BSA stimulated the DNA-binding activity of activator protein-1 (AP-1). Promoter assay showed that the induction of VEGF was dependent on AP-1. The activity of Ras/Raf-1/MEK/ERK1/2 was involved in the CML-BSA-stimulated signaling pathways to activate the AP-1 transcription with a peak at 1 h. AGE-BSA also induced VEGF mediated by AP-1, however, there was a difference of effect between AGE-BSA and CML-BSA in the activation of AP-1. AGE-BSA-stimulated AP-1 activity showed a peak at 5 h, which paralleled the formation of ROS. Reduction of AGE-BSA with NaBH(4) or addition of vitamin E attenuated the AGE-BSA-stimulated signaling pathways leading to the same pattern as for CML-BSA-stimulated signals. These results suggest an important role for AGEs in stimulation of the development of angiogenesis observed in diabetic complications, and that ROS accelerates the AGE-stimulated VEGF expression.

Inhibitory effect on expression of angiogenic factors by antiangiogenic agents in renal cell carcinoma.

Since it has been widely recognised that renal cell carcinoma is refractory to standard therapies such as chemotherapy and radiotherapy, a new modality of treatment is needed. One of the potential alternative therapies for renal cell carcinoma may be inhibition of angiogenesis. In this study, we analysed the inhibitory effects of several potential agents on expression of angiogenic factors such as vascular endothelial growth factor and basic fibroblast growth factor, which are the main mediators in angiogenesis of renal cell carcinoma. We used medroxyprogesterone acetate, interferon-alpha, interferon-gamma, minocycline hydrochrolide and genistein, which are known to be antiangiogeneic. Northern blot analyses revealed that, among the five agents examined, genistein had a strong inhibitory effect on expression of vascular endothelial growth factor mRNA and basic fibroblast growth factor mRNA. Medroxyprogesterone acetate and interferon-alpha did not significantly decrease the level of either vascular endothelial growth factor mRNA or basic fibroblast growth factor mRNA. Interferon-gamma and minocycline had mild inhibitory effects on vascular endothelial growth factor mRNA and basic fibroblast growth factor mRNA expression. Genistein also inhibited both vascular endothelial growth factor mRNA and basic fibroblast growth factor mRNA expression after treatment with epidermal growth factor and hypoxia. These findings suggest that one of the mechanisms of the inhibition of angiogenesis by genistein is suppression of the expression of the angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor in renal cell carcinoma.

Increased expression of Vascular Endothelial Growth Factor-A in seasonal allergic rhinitis.

Increased vascular dilatation and permeability characterize allergic rhinitis. In this study oligonucleotide microarrays (Affymetrix HuGe95A) were used to identify differentially expressed vasoactive genes in nasal biopsies from 23 patients with symptomatic seasonal allergic rhinitis (SAR) and 12 healthy controls. RNA was extracted from the biopsies and pooled in three patient and three control pools. Out of 12,626 analysed transcripts, 39 were higher and 81 lower in the patients. Of these transcripts two have vasoactive effects: Vascular Endothelial Growth Factor-A (VEGF-A) and the Beta-1-Adrenergic Receptor. Both were higher in patients than in controls. The mean +/- SEM expression levels in arbitrary units of VEGF-A were 130 +/- 123 in the patients and 59 +/- 53 in the controls. The fold ratio in expression levels between patients/controls was 2.2. The corresponding values for the beta-1-adrenergic receptor were 129 +/- 123 in the patients and 40 +/- 31 in the controls. The fold ratio between patient/controls was 3.2. The role of VEGF-A was assessed by determining VEGF-A concentrations in nasal fluids from another 30 patients with SAR before and after allergen provocation. VEGF-A increased from 124.3 +/- 30.2 to 163.2 +/- 37.8 pg/ml after challenge, P < 0.05. In summary, oligonucleotide microarray analysis of nasal biopsies and protein analyses of nasal fluids indicate that VEGF-A may be an important mediator in SAR.

[Effect of bizhongxiao decoction on the expression of VEGF in the synovial membrane of C II-induced rheumatoid arthritis in rats].

OBJECTIVE: To observe the effect of bizhongxiao (BZX) decoction on the expression of VEGF in the synovial membrane of C II-induced arthritis(CIA) in rats and to explore the mechanism of BZX decoction in the treatment of rheumatoid arthritis RA. METHODS: Seventy-five SD rats were randomly divided into four groups. The rat experimental arthritis model was established by subcutaneous injection of II collogen. The expression of VEGF was detected with immunohistochemistry in different times. RESULTS: The incidence of arthritis in the rats immunized with C II was approximately 88.57%. The arthritis index of the model group was rising, but that of the BZX decoction group and the methotrexate (MTX) group were decreasing on the 30th day. No expression of VEGF was found in the synovial membrane of the normal group. The expression of VEGF of the model group was notably higher than that of the BZX decoction group and the MTX group in different times (P < 0.01). The expression of VEGF of the model group rose step by step, but that of the BZX decoction group and the MTX group decreased and was significantly lower than that of the model group (P < 0.01). The expression of VEGF of the BZX decoction group was significantly lower than that of the MTX group(P < 0.05). CONCLUSION: The expression of VEGF is relative to the synovial pannus formation in RA. BZX decoction and MTX could decrease the expression of VEGF, but the curative effect of BZX decoction is significantly better than that of MTX. BZX decoction could inhibit the formation of the synovial pannus or bone in RA by decreasing the expression of VEGF.

Inhibition of angiogenesis-driven Kaposi's sarcoma tumor growth in nude mice by oral N-acetylcysteine.

The thiol N-acetyl-L-cysteine (NAC), an analogue and precursor of reduced glutathione, has cancer chemopreventive properties attributable to its nucleophilicity, antioxidant activity, and a variety of other mechanisms. We demonstrated recently that NAC has anti-invasive, antimetastatic, and antiangiogenic effects in in vitro and in vivo test systems. In the present study, s.c. transplantation of KS-Imm cells in (CD-1)BR nude mice resulted in the local growth of Kaposi's sarcoma, a highly vascularized human tumor. The daily administration of NAC with drinking water, initiated after the tumor mass had become established and detectable, produced a sharp inhibition of tumor growth, with regression of tumors in half of the treated mice along with a markedly prolonged median survival time. The production of vascular endothelial growth factor (VEGF) and certain proliferation markers (proliferating cell nuclear antigen and Ki-67) were significantly lower in Kaposi's sarcomas from NAC-treated mice than from control mice. Treatment of KS-Imm cells with NAC in vitro resulted in a dose-dependent inhibition of chemotaxis and invasion through inhibition of gelatinase-A (matrix metalloproteinase-2, MMP-2) activity without altering MMP-2 or MMP-9 mRNA levels. NAC also significantly inhibited VEGF production but did not affect proliferation markers in vitro. Reverse transcription-PCR analysis indicated that total VEGF mRNAs were reduced by 10 mM NAC. Taken together, these findings provide evidence that NAC, the safety of which even at high doses has been established in almost 40 years of clinical use, in addition to its chemopreventive action, has a strong antiangiogenic potential that could be exploited for preventing cancer progression as well as used in cancer adjuvant therapy.

Upregulation of oxidant-induced VEGF expression in cultured keratinocytes by a grape seed proanthocyanidin extract.

Angiogenesis plays a central role in wound healing. Among many known growth factors, vascular endothelial growth factor (VEGF) is believed to be the most prevalent, efficacious, and long-term signal that is known to stimulate angiogenesis in wounds. The wound site is rich in oxidants such as hydrogen peroxide mostly contributed by neutrophils and macrophages. Proanthocyanidins or condensed tannins are a group of biologically active polyphenolic bioflavonoids that are synthesized by many plants. This study provides first evidence showing that natural extracts such as grape seed proanthocyanidin extract containing 5000 ppm resveratrol (GSPE) facilitates oxidant-induced VEGF expression in keratinocytes. Using a ribonuclease protection assay (RPA), the ability of GSPE to regulate oxidant-induced changes in several angiogenesis-related genes were studied. While mRNA responses were studied using RPA, VEGF protein release from cells to the culture medium was studied using ELISA. Pretreatment of HaCaT keratinocytes with GSPE upregulated both hydrogen peroxide as well as TNF-alpha-induced VEGF expression and release. The current results suggest that GSPE may have beneficial therapeutic effects in promoting dermal wound healing and other related skin disorders.

Regulation of vascular endothelial growth factor transcription by endothelial PAS domain protein 1 (EPAS1) and possible involvement of EPAS1 in the angiogenesis of renal cell carcinoma.

BACKGROUND: Endothelial PAS domain protein 1 (EPAS1) is a basic helix-loop-helix/PAS domain transcription factor that expressed most abundantly in highly vascularized organs. The authors examined the effect of transfection of EPAS1 cDNA on the endogenous expression of vascular endothelial growth factor (VEGF) in the 293 Tet-Off cell line and the possible involvement of EPAS1 in the angiogenesis of renal cell carcinoma (RCC). METHODS: Complete cDNA of EPAS1 was cloned and transfected to cells from the 293 Tet-Off fetal kidney cell line, in which the expression of EPAS1 can be inhibited by doxycycline. The subsequent changes in expression pattern of VEGF and transferrin receptor (TfR), a target gene of hypoxia-inducible factor 1alpha (HIF-1alpha), were examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay. In addition, expression of EPAS1, HIF-1alpha, and VEGF were analyzed by semiquantitative RT-PCR in five RCC cell lines and in 13 RCC tissue samples. In situ hybridization was performed on 7 of the 13 RCC tissue samples. RESULTS: Endogenous VEGF was increased significantly by the introduction of EPAS1 cDNA at both the mRNA level and the protein level. With the inhibition of EPAS1 by doxycycline treatment, the expression of VEGF was significantly decreased accordingly, whereas the expression of TfR was not affected. EPAS1 was detected in all of the RCC cell lines examined. In RCC tissue samples, EPAS1 mRNA and VEGF mRNA were increased significantly in tumor tissues compared with normal adjacent kidney tissues. In situ hybridization showed that EPAS1 and VEGF were coexpressed topographically in tumor tissues. CONCLUSIONS: These results suggest that endogenous VEGF can be up-regulated transcriptionally by EPAS1, and EPAS1 may be involved in the angiogenesis of RCC.

Vascular endothelial growth factor expression, S-phase fraction and thymidylate synthase quantitation in node-positive colon cancer: relationships with tumor recurrence and resistance to adjuvant chemotherapy.

BACKGROUND: The behaviour of colorectal carcinomas may depend on molecular properties of tumors. In node-positive colon cancer, we assessed the S-phase fraction (SPF) index, the vascular endothelial growth factor (VEGF) expression and the TS levels. The combined analysis of SPF/VEGF was studied for predictivity of recurrent disease, the TS quantitation was related to the efficacy of fluorouracil-based adjuvant chemotherapy. PATIENTS AND METHODS: Consecutive patients with surgically-resected, node-positive colon cancer were studied. Flow cytometry for the SPF and immunohistochemistries for the TS and the VEGF expression were carried out on the primary tumor. Recurrences had to be proven by biopsy or surgery, and they were categorized as early, if occurred within 12 months after surgery, or late if occured 13 months or more. RESULTS: Of 150 evaluable patients, 100 had received fluorouracil-based adjuvant chemotherapy and 50 control patients were untreated. The combined analysis of the VEGF and the SPF showed a strong association between the two markers; 48 patients (32%) had high SPF/VEGF positive tumors and 69 patients (46%) had low SPF/VEGF negative tumors (P < 0.0001). The majority of disease-free patients (73.4%) showed VEGF negative/low SPF tumors (P < 0.0001). Early recurrences occurred more frequently in patients with VEGF positive/high SPF tumors (P < 0.001). In the 100 patients treated with adjuvant chemotherapy, 86% of relapsed patients had TS overexpressing tumors and 69% of disease-free patients had TS negative tumors (P < 0.001). Also, early recurrences occurred more frequently in TS overexpressing tumors (P < 0.0001). CONCLUSIONS: Evidence is supported that node-positive colon cancer constitutes a heterogenous disease. Patients with VEGF positive/high SPF tumors showed an unfavourable outcome compared to patients with VEGF negative/low SPF tumors. The efficacy of fluorouracil-based adjuvant chemotherapy may depend on the TS status.