Peritumoral Microvessel Density Research Articles

Antitumor and antiangiogenic effects of Tonantzitlolone B, an uncommon diterpene from Stillingia loranthacea.

Natural products have played a pivotal role for the discovery of anticancer drugs. Tonantzitlolones are flexibilan-type diterpenes rare in nature; therefore, few reports have shown antiviral and cytotoxic activities. This study aimed to investigate the in vivo antitumor action of Tonantzitlolone B (TNZ-B) and its toxicity. Toxicity was evaluated in mice (acute and micronucleus assays). Antitumor activity of TNZ-B (1.5 or 3mg/kg intraperitoneally - i.p.) was assessed in Ehrlich ascites carcinoma model. Angiogenesis and reactive oxygen species (ROS) and nitric oxide (NO) production were also investigated, in addition to toxicological effects after 7-day treatment. The LD50 (lethal dose 50%) was estimated at around 25mg/kg (i.p.), and no genotoxicity was recorded. TNZ-B reduced the Ehrlich tumor's volume and total viable cancer cell count (p < 0.001 for both). Additionally, TNZ-B reduced peritumoral microvessel density (p < 0.01), suggesting antiangiogenic action. Moreover, a decrease was observed on ROS (p < 0.05) and nitric oxide (p < 0.001) levels. No significant clinical findings were observed in the analysis of biochemical, hematological, and histological (liver and kidney) parameters. In conclusion, TNZ-B exerts antitumor and antiangiogenic effects by reducing ROS and NO levels and has weak in vivo dose-repeated toxicity. These data contribute to elucidate the antitumor action of TNZ-B and point the way for further studies with this natural compound as an anticancer drug.

Angiogenesis and Lymphangiogenesis in Salivary Gland Adenoid Cystic Carcinoma and Mucoepidermoid Carcinoma.

Background and Purpose:This study aimed to investigate the immunohistochemical expression of CD31 and podoplanin in order to examine angiogenesis and lymphangiogenesis, respectively in common malignant tumors of salivary glands. Materials and Methods:Forty formalin-fixed, paraffinated blocks (20 adenoid cystic carcinoma and 20 mucoepidermoid carcinoma blocks) were selected from the medical archives of Amir A’lam Hospital of Tehran, Iran. Sections from the blocks were stained by CD31 and D2-40 markers via immunohistochemistry. Clinical and demographic information was extracted from the patients’ records. Findings:There was a significant difference between tumors in terms of intratumoral microvessel density (MVD) (P< 0.001), total MVD (P< 0.001), and intratumoral lymphatic vessel density (LVD) (P= 0.011). In mucoepidermoid carcinoma, intratumoral MVD and LVD were greater than peritumoral MVD and LVD (P= 0.001 and P< 0.001, respectively). In mucoepidermoid carcinoma, there was no relationship between histological grade with MVD (total, intratumoral or peritumoral) or LVD (total, intratumoral or peritumoral) (P> 0.05). A similar finding was reported with respect to the histopathological grade of adenoid cystic carcinoma (P> 0.05). Conclusion:The higher level of angiogenesis and lymphangiogenesis in mucoepidermoid carcinoma, specifically at the center of tumor, compared to adenoid cystic carcinoma, may be attributed to differences in the clinical behaviors and metastasis of tumors. Moreover, considering the high LVD at the center of tumor in mucoepidermoid carcinoma and infrequency of metastasis to regional lymph nodes in adenoid cystic carcinoma, it can play a significant role in metastasis to regional lymph nodes.

Prognostic implications of peritumoral vasculature in head and neck cancer.

BackgroundThere is conflicting evidence regarding the role of peritumoral lymphatic vessel density (LVD) and blood microvessel density (MVD) in the metastasis and prognosis of head and neck squamous cell carcinoma (HNSCC). Existing studies are limited to one or two head and neck subsites and/or small sample sizes. A larger study incorporating multiple sub‐sites is needed to address the role of peritumoral LVD and MVD in HNSCC metastasis and prognosis.MethodsTissue samples from 200 HNSCC cases were stained simultaneously using immunohistochemistry (IHC) for markers of peritumoral LVD (lymphatic vessel marker D240) and MVD (blood vessel marker CD31). Of the stained slides, 166 and 167 were evaluable for LVD and MVD, respectively. The results were then correlated with clinicopathologic features and patient outcomes.ResultsPatients with metastatic disease were more likely to have high peritumoral MVD. Through multivariable analyses, MVD was not significantly related to DFS and OS, while low LVD was related to higher risk of disease progression and poor survival.ConclusionsPeritumoral MVD was found to be positively associated with metastasis, while LVD was found to be inversely related to both metastasis and progression of HNSCC. These findings may suggest a prognostic role of both peritumoral LVD and MVD in patients with HNSCC.

The importance of microvessel density in predicting cancer progression in patients with penile squamous cell carcinoma.

To evaluate the role of microvessel density (MVD) in predicting lymph node (LN) metastasis in penile squamous cell carcinoma (PSCC). Records of 266 patients with PSCC were analyzed. Parameters examined were tumor stage, grade, nodal status, intratumoral and peritumoral MVD. Univariate and multivariate analyses were used to evaluate association between different histopathological variables and MVD. ROC was plotted to derive a prediction model using appropriate cutoff values of the parameters predicting cancer progression. 77 patients were found to have histologically proven metastatic LN. MVD did not correlate significantly with T stage and grade of tumor. The intratumoral and peritumoral MVD of patients with metastatic LN was significantly higher than patients with negative LN (58.92 vs. 49.89 and 65.57 vs. 53.72, respectively; P<0.0001). Multivariate analysis also revealed that MVD (intratumoral and peritumoral) was independent predictor for LN metastasis. From ROC curve, at the cutoff value of 54, intratumoral MVD predicted LN metastasis with sensitivity of 91% and specificity of 87%. Similarly, at cutoff value of 61, peritumoral MVD predicted LN metastasis with sensitivity of 94% and specificity of 89%. The 5-year survival was 79 and 77% for those with low intratumoral and peritumoral MVD, respectively, as compared to 41 and 39% for those with high intratumoral and peritumoral MVD, respectively (P<0.05). Higher intratumoral and peritumoral MVD predicts cancer progression in patients with PSCC. Patients with an intratumoral MVD of 54 and peritumoral MVD of 61 have lymph node metastasis with a high sensitivity and specificity. The overall 5-year survival of patients is poor in high intratumoral or peritumoral MVD.

Effect of Hyperbaric Oxygen on the Growth of Intracranial Glioma in Rats.

Background:Numerous studies have confirmed that hyperbaric oxygen (HBO) in combination with radiotherapy or chemotherapy may increase the efficacy of radiotherapy or chemotherapy in patients with glioma. However, whether HBO therapy alone may inhibit or promote the growth of malignant tumors remains controversial. This study aimed to investigate the effect of HBO on the growth of glioma in rats, and the impact of HBO on the expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1-alpha (HIF-1α), angiogenesis, and apoptosis of glioma cells.Methods:Male Sprague–Dawley rats were treated with or without HBO after glioma cell inoculation and followed for up to 16 days postinoculation. Rats were randomized to receive bilateral forelimb function tests (n = 20 per group) and head magnetic resonance imaging (n = 5 per group). Differences between HBO and control groups were tested using 2-sample independent t-tests and changes over time within treatment groups were analyzed using a repeated measurement analysis of variance with Bonferroni correction. The effect of HBO on the expression of VEGF, HIF-1α, von Willebrand factor, angiogenesis, and tumor cell apoptosis were also examined (n = 5 per group).Results:Forelimb function scores were reduced in both HBO-treated and control groups. HBO-treated rats had significantly larger tumor volume and more water in the cerebellum compared with control rats. The intratumoral expression of VEGF was significantly higher in HBO-treated rats compared with control rats (23.2% vs. 13.3%, P = 0.002). HIF-1α was significantly increased in HBO-treated rats compared with controls in the expression of both intratumoral (72.7% vs. 54.9%, P = 0.001) and peritumoral (2.6% vs. 1.9%, P = 0.003) cells. The intratumoral microvessel density (MVD) was significantly higher in the HBO group (15.6 vessels/field vs. 4.4 vessels/field, P < 0.001), and the peritumoral MVD was not significantly different between the two groups (P > 0.05). Apoptosis was significantly lower in HBO-treated rats compared with controls (44.4% vs. 82.8% for intratumoral; 10.1% vs. 77.5% for peritumoral, both P < 0.001).Conclusions:The current results demonstrate that HBO alone may promote tumor growth, and is therefore not suitable to treat patients with gliomas with neurological deficits or disorders with HBO alone. If HBO must be used as a mean of rehabilitation, it is recommended that HBO should be combined with radiotherapy or chemotherapy.

Expression of Bax and Bcl-2 in Tumour Cells and Blood Vessels of Breast Cancer and their Association with Angiogenesis and Hormonal Receptors

A total of 96 cases of invasive breast ductal carcinoma were examined for immunohistochemical expression of Bax and Bcl-2 in the epithelial tumor cells and endothelial cells of the blood vessels. We also investigated the association between both proteins in the epithelium in relation to tumor characteristics such as tumor size, grade, lymph node involvement, microvessel density (MVD), hormonal receptors expression and c-erbB-2 overexpression. Bax expression showed a significant association between tumor and endothelial cells (p<0.001) while Bcl-2 expression in tumor cells was inversely associated with that in the endothelial cells (p<0.001). Expression of Bcl-2 in tumor cells was strongly associated with expression of estrogen and progesterone receptors (p=0.003 and p=0.004, respectively). In addition, intratumoral MVD was significantly higher than peritumoral MVD (p<0.001) but not associated with Bax or Bcl-2 expression and other tumor characteristics. We concluded that the number of endothelial cells undergoing apoptosis was in direct linkage with the number of apoptotic tumor cells. Anti-apoptotic activity of the surviving tumor cells appears to propagate cancer progression and this was influenced by the hormonal status of the cells. Tumor angiogenesis was especially promoted in the intratumoral region and angiogenesis was independent of anti-apoptotic activity.

Angiogenesis and lymphangiogenesis in sporadic hepatic angiomyolipoma

Angiogenesis and lymphangiogenesis are critical processes for tumor growth, invasion, and metastasis. The present study aimed to investigate the distribution and clinical significance of angiogenesis and lymphangiogenesis in hepatic angiomyolipoma (AML). We performed immunohistochemical staining for endothelial cell markers (CD34 and podoplanin) on 80 cases of sporadic hepatic AMLs. Microvessel density (MVD) and lymphatic vessel density (LVD) were determined in intratumoral and peritumoral regions and adjacent non-tumorous liver tissues. All hepatic AMLs showed positive staining for CD34 and podoplanin. Intratumoral and peritumoral MVDs and LVDs were significantly higher than those in adjacent liver tissues ( P < 0.001). No statistical difference in both MVD and LVD was found between intratumoral and peritumoral areas. Large tumors (>5 cm) had a significantly increased MVD and LVD as compared with smaller tumors. A significant positive correlation was found between average LVDs and MVDs ( r = 0.567, P < 0.001), and LVDs were a relatively lower event as compared with MVDs. Double immunostaining revealed that no neoplastic cells positive for HMB-45, an antibody reacting with melanosome-associated antigen, were concurrently immunoreactive for endothelial cell markers. In conclusion, intratumoral and peritumoral angiogenesis and lymphangiogenesis commonly occur in hepatic AMLs, thus representing potential therapeutic targets for this disease.

Microvessel density as a prognostic factor in penile squamous cell carcinoma

ObjectiveTo examine the potential effect of tumor-induced angiogenesis in squamous cell carcinoma of the penis as a possible prognostic factor. Patients and methodsImmunohistochemistry was preformed to detect microvessels in tumor samples of 64 patients with squamous cell carcinoma of the penis. We used a monoclonal mouse antibody directed against CD34 antigen. Only 61 (30 with and 31 without metastasis) patients had good staining properties and were included. After immunostaining, the entire tumor section was scanned microscopically at low power (×40) to identify hot spots within the tumor and at its periphery. Individual tumor microvessels were then counted under high power (×200) to obtain a vessel count in a defined area, and the mean of the 3 highest microvessel counts was taken as the microvessel density (MVD). Microvessel counting was performed using a computer-aided image analysis system. The nodal status was based on histopathologic examination or an uneventful follow-up ≥2 years. ResultsThe 5-year overall survival (OAS) was 75% and 30 % for those with high and low peritumoral MVD, respectively (log rank P = 0.01). No difference was noticed within the tumor with regard to high (5-year OAS of 65.03%) and low (5-year OAS of 60.56%) intratumoral MVD (log rank P = 0.99). The mean intratumoral MVD was 32.35 (3.16), 37.94 (3.35), and 62.66 (5.47) in T1, T2, and T3 respectively (ANOVA P = 0.0006), with increasing tendency. The mean peritumoral MVD was 55.91 (5.60), 56.8 (4.00), and 78.86 (8.71), respectively (P = 0.06). No correlation between MVD lymph node status and tumor grade was seen (P > 0.05). ConclusionIn our group of patients, a high peritumoral MVD was associated with a better 5-year OAS. However, for a reliable and reproducible assessment of tumor angiogenesis in penile squamous cell carcinoma, validation procedures and quality control protocols are mandatory.

Increased Intratumoral Lymphatic Vessel Density Correlates with Lymph Node Metastasis in Early Gastric Carcinoma

Prediction of lymph node metastasis in early gastric carcinoma (EGC) is important for management and follow-up of EGC patients. Increased lymphangiogenesis has been suggested to correlate with lymphatic invasion and lymph node metastasis in various tumors. Lymphatic vessel density (LVD) and microvessel density (MVD) of 141 EGCs were determined by double immunohistochemical staining for D2-40 and CD31. The mean values of three to five hotspots were calculated in intratumoral and peritumoral areas in digital images. The mean value of intratumoral LVD in a lymph-node-positive EGC group was 28.24/field, which was significantly higher than in a lymph-node-negative EGC group (19.43/field, P = 0.005). Peritumoral LVD, intratumoral MVD, and peritumoral MVD did not correlate with lymph node metastasis in EGCs (P > 0.05). Intratumoral LVD did not show significant differences according to lymphatic invasion and differentiation, which were positive predictors for lymph node metastasis in EGC. Using multivariate logistic regression, intratumoral LVD was an independent factor, with the above two factors and depth of invasion, for the prediction of lymph node metastasis in EGC with a relative risk of 3.570 in high-intratumoral-LVD group compared with low-intratumoral-LVD group (P = 0.022). Intratumoral LVD may be a useful, independent predictor for lymph node metastasis, especially in combination with previously established predictors in EGC.

Tumor Angiogenesis in Oral Squamous Cell Carcinomas: The Significance of Endothelial Markers and Hotspot Selection

The intensity of angiogenesis affects the prognosis for many malignant tumors, but there is no consensus about the association between the prognosis of oral squamous cell carcinoma (OSCC) and the intensity of angiogenesis. This discrepancy might be caused by different endothelial markers used and by hotspot selection. The aim of this study was to investigate the sensitivity and specificity of different endothelial markers for evaluating microvessel density (MVD) in OSCCs. We also examined the effect of hotspot area selection in association with clinicopathological features of OSCCs. Methods: We collected 84 OSCC specimens for immunohistochemical staining for three common endothelial makers: van Willebrand factor (vWF), CD31 and CD34. Peritumoral and intratumoral vascular hotspot areas were selected separately for MVD counting. Results: There was no significant association between peritumoral MVD and clinicopathological parameters. However, the intratumoral MVDs determined using CD31 and CD34 were significantly associated with tumor size (P=0.003 and P＜0.0001, respectively), with histological differentiation (P=0.0025 and P=0.018, respectively) and with tumor stage (P=0.001 and P＜0.0001, respectively). In addition, the intratumoral MVD counted using CD34 immunostaining was significantly associated with lymph node metastasis of OSCC (P=0.005). Conclusions: Tumor angiogenesis and the density of newly formed vessels are of potential prognostic relevance in the assessment of malignant neoplasia. The endothelial marker CD34 was better in the assessment of tumor vascularization of OSCCs. Furthermore, hotspot selection, especially intratumoral MVD, is important in examining OSCC progression.

Significance of VEGF-C and VEGF-D in lymphatic metastasis of pancreatic cancer

Objective To analyze the intratumoral and peritumoral microvessel density (MVD) and microlymphatic vessel density (MLVD) in pancreatic cancer and record the expression of vascular endothelial growth factor(VEGF)-C and VEGF-D. And to explore the significance of VEGF-C and VEGF-D during the lymphatic metastasis and development of pancreatic cancer. Methods The expression of VEGF-C and VEGF-D, VEGF-R3, CD34 were assayed by immunohistochemical staining in 30 cases of pancreatic cancer tissues. Results The positive rates of VEGF-C and VEGF-D protein in the central portion of tumors (30% and 16.7%) were significantly lower than those in the marginal portion (73.3% and 56.7%), P <0.01. The group with high expression of VEGF-C and VEGF-D in the marginal portion had significantly higher incidences of lymph node metastasis, lymphatic invasion and venous invasion( P <0. 01 ). MLVD in both of the VEGF-C and VEGF-D positive groups was higher than that in the negative groups( P <0. 01 ), and the lymph node me-tastasis increased. MVD in VEGF-C positive group was significantly higher than that in the negative group. MVD had no significant difference between VEGF-D positive and negative group ( P =0. 07). Conclusions The expression of VEGF-C and VEGF-D in the marginal portion of tumor is significantly correlated with lym-phatic metastasis in pancreatic cancer patients, and may induce lymphangiogenesis. VEGF-C may play an im-portant role in the regulation of angiogenesis and lymphangiogenesis in pancreatic cancer, and VEGF- D maybe only participate in the regulation of lymphangiogenesis. Key words: Vascular endothelial growth factors; Pancreatic neoplasms; Lymphangiogenesis; Lym-phatic metastasis

Expression of vascular endothelial growth factors-C and -D correlate with evidence of lymphangiogenesis and angiogenesis in pancreatic adenocarcinoma

Background: We analyzed the intratumoral and peritumoral microvessel density (MVD) and microlymphatic vessel density (MLVD) in pancreatic adenocarcinoma (PAC) and recorded the expression of vascular endothelial growth factor (VEGF)-C and -D. These data were tested for their significance for tumor progression. Methods: The tissue samples were obtained from 30 patients with PAC. The expression of VEGF-C and -D, MLVD, MVD was assayed by immunohistochemical staining. The expression of VEGF-A and -C, and -D mRNA was detected by semi-quantitative RT-PCR. Results: Immunohistochemical analysis revealed the presence of VEGF-C and -D immunoreactivity in 73% (22/30) and 57% (17/30). The positive rates of VEGF-C and -D protein in central portion of tumors (30% and 16.7%) were significantly lower than those in marginal portion (73.3% and 56.7%). The group with high expression of VEGF-C and -D in marginal portion had higher incidence of lymph node metastasis, lymphatic invasion and venous invasion. The MLVD in both of the VEGF-C and -D positive groups was higher than that in the negative groups, and the lymph node metastasis increased. MVD in the VEGF-C positive group was higher than that in the negative group. Conclusions: The expression of VEGF-C and -D in the marginal portion of tumor significantly associated with lymphatic metastasis and prognosis in patients with PAC, and may induced lymphangiogenesis. VEGF-C was important in the regulation of angiogenesis and lymphangiogenesis in PAC.

Role of angiogenic and non-angiogenic mechanisms in oral squamous cell carcinoma: correlation with histologic differentiation and tumor progression.

Angiogenesis has been demonstrated to associate with various measures of tumor aggressiveness in many human malignancies. However, studies of tumor angiogenesis in oral squamous cell carcinoma (SCC) are still unclear. Recent studies indicate non-angiogenesis mechanism (tumor-lined vessel) may exist in certain tumors. Therefore, we investigate microvessel density (MVD) and tumor-lined vessel in oral SCC. Peritumoral and intratumoral MVD were measured by immunohistochemical staining. Tumor-lined vessels were identified by double staining. Statistical analysis of peritumoral and intratumoral MVD and presence of tumor-lined vessels with clinicopathologic parameters was performed. The results showed peritumoral MVD increased with disease progression and further increases of intratumoral MVD was detected by CD31 and CD34. Non-angiogenesis, tumor-lined vessel, presented in oral SCC and correlated significantly with tumor size, stage, and histologic differentiation. Our results suggest at the initiation of oral SCC, increasing vascularity is observed at the periphery of the tumor. As the tumor continues to grow, further increases of intratumoral vascularity and the presence of tumor-lined vessels are associated with cancer progression.

Prognostic relevance of tryptase and chymase positive mast cells and neoangiogenesis in colorectal carcinomas

3745 Background: Human mast cells (MC) are subdivided into two subsets according to the expression of proteases: MCt positive only for tryptase and MCtc positive for both tryptase and chymase. Their biological role in tumor progression is almost unknown. Methods: We studied the expression patterns of MCt and MCtc in relation to microvessel density (MVD) and other known clinicopathological parameters in 87 primary colorectal carcinomas (CCR) to determine their prognostic significance. Intratumoral and normal peritumoral MC and MVD (CD31+) were analyzed by immunohystochemistry. Positivity was assessed in five areas of 1.2 mm2. Areas of high number of MC and MVD positivity (“hotspot”) were also counted. Overall survival, at five years follow-up was determined. Results: A very high correlation between the two methods to evaluate MC or MDV positivity was found (p<0,01). MCt and MCtc were less frequent inside the tumor than in the normal adjacent mucosa, being MCt the predominant phenotype. A positive correlation between the number of MCt and MVD was found (p<0.01). When we analyzed the relationship between MCt, MCtc or MVD and the main clinicopathological features, we found differences in MCt and MVD according to Duke's stage classification. Thus, patients classified as Duke A always presented the lowest values for both types of MC and MCV. Besides, we found that the number of intratumoral MCt correlated positively with lymphatic and /or blood vessel invasion (p<0.05). To assess prognosis, patients were divided into two groups according to high and low MCt, MCtc or MVD expression. Univariate study indicates a non significant association between high intratumoral MCt and low MCtc. Unexpectedly, a significant association between low MVD expression and bad outcome was found. By multivariate analysis, intratumoral MVD was found to be an independent prognostic indicator. Conclusions: MCt, MCtc and MVD in CCR, is less frequent in tumors from patients with low stage. Although, high intratumoral MCt and low MCtc was observed in tumors from patients with bad outcome, only MVD showed to be an independent prognostic marker. No significant financial relationships to disclose.

Prognostic relevance of tryptase and chymase positive mast cells and neoangiogenesis in colorectal carcinomas

3745 Background: Human mast cells (MC) are subdivided into two subsets according to the expression of proteases: MCt positive only for tryptase and MCtc positive for both tryptase and chymase. Their biological role in tumor progression is almost unknown. Methods: We studied the expression patterns of MCt and MCtc in relation to microvessel density (MVD) and other known clinicopathological parameters in 87 primary colorectal carcinomas (CCR) to determine their prognostic significance. Intratumoral and normal peritumoral MC and MVD (CD31+) were analyzed by immunohystochemistry. Positivity was assessed in five areas of 1.2 mm2. Areas of high number of MC and MVD positivity (“hotspot”) were also counted. Overall survival, at five years follow-up was determined. Results: A very high correlation between the two methods to evaluate MC or MDV positivity was found (p<0,01). MCt and MCtc were less frequent inside the tumor than in the normal adjacent mucosa, being MCt the predominant phenotype. A positive correlation between the number of MCt and MVD was found (p<0.01). When we analyzed the relationship between MCt, MCtc or MVD and the main clinicopathological features, we found differences in MCt and MVD according to Duke's stage classification. Thus, patients classified as Duke A always presented the lowest values for both types of MC and MCV. Besides, we found that the number of intratumoral MCt correlated positively with lymphatic and /or blood vessel invasion (p<0.05). To assess prognosis, patients were divided into two groups according to high and low MCt, MCtc or MVD expression. Univariate study indicates a non significant association between high intratumoral MCt and low MCtc. Unexpectedly, a significant association between low MVD expression and bad outcome was found. By multivariate analysis, intratumoral MVD was found to be an independent prognostic indicator. Conclusions: MCt, MCtc and MVD in CCR, is less frequent in tumors from patients with low stage. Although, high intratumoral MCt and low MCtc was observed in tumors from patients with bad outcome, only MVD showed to be an independent prognostic marker. No significant financial relationships to disclose.

Fibroblast growth factor-binding protein expression changes with disease progression in clinical and experimental human squamous epithelium.

Basic fibroblast growth factor (bFGF) is synthesized by a wide variety of normal and malignant cells. However, bFGF cannot exert its effects unless it gets outside of the cell. Since it lacks a signal sequence to direct secretion, the method by which cells release it remains unclear. A 17 kDa secreted binding protein for bFGF (FGF-BP, HBp-17) is expressed at high levels in squamous cell carcinoma (SCC) and transformed keratinocytes and may act as a chaperone to transport bFGF outside of the cell. In our study, FGF-BP mRNA expression in normal keratinocytes was higher than in 5/5 SCCs. Using a new monoclonal antibody, we demonstrate that FGF-BP can dimerize. Immunoassays demonstrate that normal keratinocytes have a higher level of FGF-BP than SCCs. In normal human squamous epithelium, we observed diffuse, moderate to intense cytoplasmic and membranous expression of FGF-BP. Expression decreased and became focal with disease progression to invasive cancer. Injection of immortalized but non-tumorigenic HaCaT cells transduced with FGF-BP into normal human skin xenografts failed to result in tumors. Transfection of FGF-BP into the SCCs Det 562 and FaDu did not promote tumor growth more than controls, and peri-tumoral microvessel density was lower in FGF-BP-transfected than in control tumors. Taken together, these data suggest that FGF-BP expression in squamous epithelium does not play an important role in progression to invasive carcinoma.