Publications by authors named "Bucana C"

Background: We investigated the expression of CXCR4, CCR7, estrogen receptor (ER), progesterone receptor (PR) and HER2-neu in human metastatic breast cancers to determine whether these biological biomarkers were preferentially expressed in any organ-specific metastases.

Materials And Methods: CXCR4, CCR7, ER, PR and HER2-neu expression levels were evaluated by immunohistochemical staining using paraffin-embedded tissue sections of metastatic breast cancers (n = 41) obtained by either diagnostic biopsy or surgical resection.

Results: The metastatic sites included the following: bone (n = 15), brain (n = 14), lung (n = 6), liver (n = 2), and omental metastases (n = 2).

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In a placebo-controlled randomised study of the platelet-derived growth factor receptor (PDGFR) inhibitor imatinib mesylate and docetaxel in metastatic prostate cancer with bone metastases (n=116), no significant differences in progression-free and overall survival were observed. To evaluate pharmacodynamic correlates of outcomes, we assessed the association of plasma platelet-derived growth factor (PDGF) isoform kinetics and PDGFR inhibition with progression-free and overall survival by individual treatment arm. We found that in the docetaxel-placebo arm alone, the probability of decrease in PDGFR phosphorylation (Pr-Decr-pPDGFR) above 0.

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Purpose: To further assess preclinical and early clinical evidence that imatinib mesylate, a platelet-derived growth factor receptor (PDGFR) inhibitor, modulates taxane activity in prostate cancer and bone metastases, a randomized study was conducted.

Experimental Design: Men with progressive castration-resistant prostate cancer with bone metastases (n = 144) were planned for equal randomization to i.v.

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Background: Colorectal carcinomas (CRC) express high levels of insulin-like growth factor-I/II (IGF-I/II) and the receptor (IGF-IR). We hypothesized that selective inhibition of IGF-IR would inhibit hepatic growth of human CRC in mice.

Methods: Human CRC cells were treated in vitro with anti-IGF-IR monoclonal antibody (MoAB) with and without oxaliplatin to assess cytotoxicity.

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We hypothesized that overexpression of PDGF-BB in colorectal cancer (CRC) and pancreatic cancer cells would result in increased pericyte coverage of ECs in vivo, rendering the tumor vasculature more resistant to antiangiogenic therapy. We stably transfected the cDNA for the PDGF-B into HT-29 human CRC and FG human pancreatic cancer cells. Surprisingly, when HT-29 or FG parental and transfected cells were injected into mice (subcutaneously and orthotopically), we observed marked inhibition of tumor growth in the PDGF-BB-overexpressing clones.

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Purpose: Recent studies have indicated that expression of chemokine receptors CXCR4 and CCR7 could be an indicator of the metastatic potential of breast cancer. Expression of CXCR4 and CCR7 along with the biomarkers HER2-neu and epidermal growth factor receptor (EGFR) was investigated in inflammatory breast cancer (IBC) to evaluate their prognostic implications.

Experimental Design: CXCR4, CCR7, and EGFR were evaluated by immunohistochemical staining (IHC) of paraffin-embedded tissue sections.

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Purpose: Clinical trials of antiangiogenic agents used alone for advanced malignancy have been disappointing but preclinical studies suggest that the addition of radiation therapy could improve antitumor efficacy. To test the hypothesis that antiangiogenic therapy combined with radiation therapy can overcome the limitations of antiangiogenic monotherapy, we studied the effects of endostatin combined with radiation on the growth and vascularization of A431 human epidermoid carcinomas growing intramuscularly in the legs of mice.

Methods And Materials: Mice with established A431 human epidermoid leg tumors were treated with radiation, endostatin, both radiation and endostatin, or vehicle control.

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Bevacizumab, a humanized monoclonal antibody against vascular endothelial growth factor (VEGF), has shown antitumor activity by inhibiting tumor angiogenesis in preclinical and clinical studies. However, bevacizumab monotherapy does not induce complete tumor regression. Therefore, additional treatments must be combined with bevacizumab to promote tumor regression.

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Objective: To study the expression of integrin-linked kinase (ILK) in human squamous cell carcinoma of the head and neck (SCCHN) tumor specimens and cell lines and the efficacy of the novel small molecule QLT0267.

Design: Immunohistochemical analysis of 17 SCCHN tumor tissue specimens and 3 normal tongue tissue specimens for ILK expression and in vitro analysis of the effectiveness of QLT0267 on SCCHN cells.

Setting: Academic medical center.

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Dogma dictates that brain metastasis originate from the proliferation of extravasated tumor cells and that the blood-brain barrier (BBB) prevents the delivery of chemotherapeutic drugs to the tumors. The purpose of this study was to clarify the relationship between tumor localization and progression and the involvement of BBB function in a murine model of breast cancer brain metastasis. Green fluorescent protein expressing MDA-MB435 breast cancer cells were injected into the left ventricle of nude mice.

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The stromal cells within colon carcinoma express high levels of the platelet-derived growth factor receptor (PDGF-R), whereas colon cancer cells do not. Here, we examined whether blocking PDGF-R could inhibit colon cancer growth in vivo. KM12SM human colon cancer cells were injected subcutaneously (ectopic implantation) into the cecal wall (orthotopic implantation) or into the spleen (experimental liver metastasis) of nude mice.

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Purpose: Intravenous (IV) delivery of siRNA incorporated into neutral liposomes allows efficient delivery to tumor tissue, and has therapeutic efficacy in preclinical proof-of-concept studies using EphA2-targeting siRNA. We sought to determine whether intraperitoneal (IP) delivery of these siRNA complexes was as effective at delivery and therapy as IV delivery.

Experimental Design: SiRNA was incorporated into the neutral liposome 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC).

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Platelet-derived growth factor receptor (PDGF-R) expression has been reported in a variety of cancers, including colorectal, breast, lung, ovarian and pancreatic cancers, but the role of PDGF-R expression in the development and progression of colon carcinoma has not yet been elucidated. The purpose of this study was to examine the expression of PDGF and PDGF-R in human colon carcinomas. The expression of PDGF, PDGF-R and phosphorylated PDGF-R (p-PDGF-R) was examined by immunofluorescence in 12 surgical specimens of colon carcinoma and in human colon carcinoma cells growing in the subcutis (ectopic site) and the cecal wall (orthotopic site) of nude mice.

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Psoralen plus UVA (PUVA) is used as a very effective treatment modality for various diseases, including psoriasis and cutaneous T-cell lymphoma. PUVA-induced immune suppression and/or apoptosis are thought to be responsible for the therapeutic action. However, the molecular mechanisms by which PUVA acts are not well understood.

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Purpose: The insulin-like growth factor-I receptor (IGF-IR) and its ligands have been implicated in the pathogenesis and progression of various cancers, including those arising in the thyroid gland. We therefore evaluated whether the IGF-IR could serve as a potential target for therapy of anaplastic thyroid carcinoma (ATC).

Experimental Design: The expression and activation of the IGF-IR and some of its downstream signaling pathway components were evaluated in both human thyroid cancer specimens and thyroid cancer cell lines.

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Background: Recent studies have suggested that chemokine receptors are involved in development of organ-specific pattern of metastases. In the present study, we evaluated the association between the chemokine receptors expressed in primary tumor cells and the site of metastatic relapse in patients with breast cancer.

Methods: Primary tumors were obtained from 142 patients with axillary node-positive breast cancer and stained for CX3CR1, CXCR4, CCR6, and CCR7 expression.

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Therapies that target signaling pathways critical to the pathogenesis and progression of squamous cell carcinoma of the head and neck (HNSCC) are needed. One such target, phosphatidylinositol 3-kinase, and its downstream target serine/threonine kinase, Akt, are up-regulated in HNSCC. Targeted therapy could consist of inhibitors of these kinases or, alternatively, of inhibitors of the pathways that they regulate.

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Objectives/hypothesis: Vascular endothelial growth factor (VEGF) is an important mediator in tumor vascularization, growth, and metastasis. We investigated whether blockade of the VEGF receptor (VEGF-R) signaling pathway by the tyrosine kinase inhibitor PTK787 combined with CPT-11, a semisynthetic camptothecin analogue, can inhibit the tumor growth and angiogenesis of squamous cell carcinoma of the oral tongue in an orthotopic nude mouse model.

Methods: JMAR human oral squamous cell carcinoma cells were injected into the tongues of nude mice.

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Although gemcitabine has been approved as the first-line chemotherapeutic reagent for pancreatic cancer, its response rate is low and average survival duration is still only marginal. Because epidermal growth factor receptor (EGFR), vascular endothelial growth factor receptor (VEGFR), and platelet-derived growth factor receptor (PDGFR) modulate tumor progression, we hypothesized that inhibition of phosphorylation of all three on tumor cells, tumor-associated endothelial cells, and stroma cells would improve the treatment efficacy of gemcitabine in an orthotopic pancreatic tumor model in nude mice and prolong survival. We implanted L3.

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Purpose: This phase I study was conducted to assess the tolerability, pharmacokinetics, and antitumor activity of the oral, selective epidermal growth factor receptor tyrosine kinase inhibitor PKI166 in patients with advanced solid malignancies.

Experimental Design: PKI166 was first given once daily continuously and in the second part of the study once daily for 2 weeks every 4 weeks to establish the maximum tolerated dose (MTD). Ten additional patients were studied at MTD to acquire additional safety information and characterize the effect of food intake on PKI166 pharmacokinetics.

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Pancreatic carcinomas express high levels of urokinase-type plasminogen activator (uPA) and its receptor (uPAR), both of which mediate cell migration and invasion. We investigated the hypotheses that (a) insulin-like growth factor-I (IGF-I)- and hepatocyte growth factor (HGF)-mediated migration and invasion of human pancreatic carcinoma cells require uPA and uPAR function and (b) inhibition of uPAR inhibits tumor growth, retroperitoneal invasion, and hepatic metastasis of human pancreatic carcinomas in mice. Using transwell assays, we investigated the effect of IGF-I and HGF on L3.

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Inducing destruction of specific mRNA using small interfering RNA (siRNA) is a powerful tool in analysis of protein function, but its use as a therapeutic modality has been limited by inefficient or impractical delivery systems. We have used siRNA incorporated into the neutral liposome 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC) for efficient in vivo siRNA delivery. In nude mice bearing i.

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Patients suffering from bone metastases of follicular thyroid carcinoma (FTC) have a poor prognosis because of the lack of effective treatment strategies. The overexpression of epidermal growth factor receptor (EGFR) associated with increased vascularity has been implicated in the pathogenesis of FTC and subsequent bone metastases. We hypothesized that inhibiting the phosphorylation of the EGFR and vascular endothelial growth factor receptor (VEGFR) by AEE788, a dual tyrosine kinase inhibitor of EGFR and VEGFR, in combination with paclitaxel would inhibit experimental FTC bone lesions and preserve bone structure.

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Purpose: We investigated whether concomitant blockade of the epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor (VEGFR) signaling pathways by AEE788, a dual inhibitor of EGFR and VEGFR tyrosine kinases, would inhibit the growth of cutaneous squamous cell carcinoma (SCC) cells and human cutaneous cancer xenografts in nude mice.

Experimental Design: We examined the effects of AEE788 on the phosphorylation of EGFR and VEGFR-2 in cutaneous SCC cells expressing EGFR and VEGFR-2 and cutaneous SCC cell growth and apoptosis. We assessed the in vivo antitumor effects of AEE788 in a xenograft model in nude mice.

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Background: We previously reported that relative expression of E-cadherin, matrix metalloproteinases (MMPs)-2 and -9, and vascular endothelial growth factor (VEGF)/vascular permeability factor in radical prostatectomy specimens (RP) can distinguish organ-confined cancers from advanced prostate cancers. Here, we evaluate the expression of interleukin-8 (IL-8) and basic fibroblast growth factor (bFGF), two other genes involved in angiogenesis and metastasis, in RP specimens.

Methods: The expression level of IL-8 and bFGF mRNA in the invasive edge of 41 prostate cancers of different stages was determined using a rapid colorimetric in situ hybridization (ISH) technique.

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