Propranolol may revolutionize the treatment of problematic hemangiomas that cause imminent functional or cosmetic sequelae. At therapeutic doses, propranolol is safe and effective in the majority of patients. Adjunctive therapies may still be required. Minor side effects, expected from beta-blocker therapy, are common but easily managed.

To participate as co-receptor in growth factor signaling, heparan sulfate must have specific structural features. Recent studies show that when the levels of 6-O-sulfation of heparan sulfate are diminished by the activity of extracellular heparan sulfate 6-O-endosulfatases (Sulfs), fibroblast growth factor 2-, heparin binding epidermal growth factor-, and hepatocyte growth factor-mediated signaling are attenuated. This represents a novel mechanism for regulating cell growth, particularly within the tumor microenvironment where the Sulfs are known to be misregulated. To directly test the role of Sulfs in tumor growth control in vivo, a human myeloma cell line was transfected with cDNAs encoding either of the two known human endosulfatases, HSulf-1 or HSulf-2. When implanted into severe combined immunodeficient (SCID) mice, the growth of these tumors was dramatically reduced on the order of 5-to 10-fold as compared with controls. In addition to an inhibition of tumor growth, these studies revealed the following. Heparan sulfate proteoglycans act as co-receptors for numerous heparin-binding growth factors and cytokines and are thus key regulators of cell signaling (1). Previous studies have demonstrated that growth factor binding to heparan sulfate and the resulting mitogenic activity occur only when specific structural features are present within the heparan sulfate chains. These features include sulfation at specific positions within a disaccharide (N, 2-O, 3-O, 6-O) by the enzymes that orchestrate heparan sulfate synthesis within the Golgi (2). However, recent studies show that following its synthesis and expression, heparan sulfate can also be structurally and functionally modified within the extracellular compartment. The two enzymes presently known to have these effects are heparanase, which cleaves heparan sulfate chains into small, biologically active fragments, and the heparan sulfate 6-O-endosulfatases (Sulfs).2 Sulfs represent a newly discovered family of enzymes that are secreted via the Golgi and become localized to the cell surface or are released into the extracellular matrix. These enzymes selectively remove the 6-O-sulfate groups from heparan sulfate with preference for the 6-O-sulfates present on trisulfated disaccharides (3, 4).The first member of the endosulfatase family to be described was sulfatase-1 from quail (QSulf1), where the activity of this enzyme is required for Wnt-mediated signaling in developing muscle (5). In separate studies, Qsulf1 was shown to restore bone morphogenetic protein signaling in cells by releasing its functional inhibitor, Noggin, from cell surfaces (3). In contrast, QSulf1 can also inhibit growth factor signaling, as removal of the 6-O-sulfation required for the formation of the FGF⅐HS⅐FR1c ternary complex blocks FGF2 signaling (6). Thus, the Sulfs can have activities that promote or inhibit growth factor signaling depending on the specific factor involved.In addition to quail, the Sulf-1 enzyme has also been cloned from rat, mouse, and human, and a second family me...

The heparan sulfate proteoglycan syndecan-1 is expressed by myeloma cells and shed into the myeloma microenvironment. High levels of shed syndecan-1 in myeloma patient sera correlate with poor prognosis and studies in animal models indicate that shed syndecan-1 is a potent stimulator of myeloma tumor growth and metastasis. Overexpression of extracellular endosulfatases, enzymes which remove 6-O sulfate groups from heparan sulfate chains, diminishes myeloma tumor growth in vivo. Together, these findings identify syndecan-1 as a potential target for myeloma therapy. Here, 3 different strategies were tested in animal models of myeloma with the following results: (1) IntroductionSyndecan-1 (CD138) is a cell-surface heparan sulfate-bearing proteoglycan that was first detected by polymerase chain reaction (PCR) in mRNA from human patients with myeloma and later confirmed by monoclonal antibody staining to be present on all myeloma tumors. 1,2 Syndecan-1 is shed from the myeloma tumor cell surface and accumulates in the bone marrow and serum of patients. When present at high levels in the serum, syndecan-1 is an independent indicator of poor prognosis. [3][4][5] However, high-serum syndecan-1 is more than simply an indicator of poor prognosis. Studies in animal models have shown that high levels of soluble syndecan-1 enhance both the growth and metastasis of tumors. 6 Syndecan-1 exerts its growth-promoting effects by regulating the activity of many effector molecules important for myeloma growth and survival, including hepatocyte growth factor (HGF) and heparin-binding epidermal growth factor (HB-EGF) family members, among others. 7,8 The high levels of heparan sulfate in the tumor microenvironment resulting from syndecan-1 shedding also act as positive regulators that condition the microenvironment for robust tumor growth. For example, heparan sulfate binds to and promotes the activity of important angiogenic growth factors such as fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF). This activity can occur in trans, indicating that shed syndecan-1 can contribute to the high level of angiogenesis seen in many patients with myeloma. 9,10 In addition, the syndecan-1 that becomes embedded within the myeloma tumor stroma can serve as reservoir for storage and concentration of heparan sulfate-binding growth factors that can later be mobilized by cleavage of the heparan sulfate by heparanase. 3,11 This mobilization of heparan sulfate-retained growth factors in the bone marrow likely contributes to the high rate of relapse among patients with myeloma.Because of its high level of expression on myeloma tumors, syndecan-1 has been explored as a candidate antigen for antibody targeting of toxins to the tumor cell surface. [12][13][14] In addition, antibodies to syndecan-1 show promise as facilitators of myeloma immunotherapeutic approaches. 15 However, specific strategies for disrupting the function of syndecan-1 or its heparan sulfate chains as a potential therapy for myeloma have not been reported...

Heparan sulfate proteoglycans (HSPGs), via their interactions with numerous effector molecules such as FGF-2, IL-8, and VEGF, regulate the biological activity of cells by acting as co-receptors that promote signaling. The extent and nature of their role as co-receptors is often misregulated in cancer as manifested by alterations in HSPG structure and expression level. This misregulation of HSPGs can aid in promoting the malignant phenotype. In addition to expressionrelated changes in HSPGs, recent discoveries indicate that HSPGs localized within the tumor microenvironment can be attacked by enzymes that alter proteoglycan structure resulting in dramatic effects on tumor growth and metastasis. This review focuses on remodeling of HSPGs by three distinct mechanisms that occur in vivo; (i) shedding of proteoglycan extracellular domains from cell surfaces, (ii) fragmentation of heparan sulfate chains by heparanase, and (iii)

Myeloma tumors are characterized by high expression of syndecan-1 (CD138), a heparan sulfate proteoglycan present on the myeloma cell surface and shed into the tumor microenvironment. High levels of shed syndecan-1 in the serum of patients are an indicator of poor prognosis, and numerous studies have implicated syndecan-1 in promoting the growth and progression of this cancer. In the present study we directly addressed the role of syndecan-1 in myeloma by stable knockdown of its expression using RNA interference. Knockdown cells that were negative for syndecan-1 expression became apoptotic and failed to grow in vitro. Knockdown cells expressing syndecan-1 at ϳ28% or ϳ14% of normal levels survived and grew well in vitro but formed fewer and much smaller subcutaneous tumors in mice compared with tumors formed by cells expressing normal levels of syndecan-1. When injected intravenously into mice (experimental metastasis model), knockdown cells formed very few metastases as compared with controls. This indicates that syndecan-1 may be required for the establishment of multi-focal metastasis, a hallmark of this cancer. One mechanism of syndecan-1 action occurs via stimulation of tumor angiogenesis because tumors formed by knockdown cells exhibited diminished levels of vascular endothelial growth factor and impaired development of blood vessels. Together, these data indicate that the effects of syndecan-1 on myeloma survival, growth, and dissemination are due, at least in part, to its positive regulation of tumor-host interactions that generate an environment capable of sustaining robust tumor growth.

Most hepatocellular carcinomas (HCCs) first occur as welldifferentiated HCCs, from which poorly differentiated HCC cells develop because of dedifferentiation. In this study, we try to clarify the changes of dedifferentiation and cell proliferative activity and their relationship in small HCCs (less than 3.0 cm in diameter) and try to learn the mechanism of these changes by analysing the expressions and genetic changes of proliferation-related genes p53 and ␤-catenin. Of 41 surgically resected small HCCs, 11 were identified to have tumor heterogeneity. DNA from the 11 small HCCs, consisting of 29 intratumoral lesions and 11 noncancerous liver tissues adjacent to HCCs, was extracted from paraffin embedded tissue sections. Exons 5-8 of p53 gene and exon 3 of ␤-catenin gene were amplified by polymerase chain reaction and analyzed by direct sequence. The serial sections were also immunostained by anti-Ki-67, p53 and ␤-catenin antibody. Immunohistochemistry showed that the p53 overexpression was significantly related to the proliferative activities as evaluated by Ki-67 immunostaining and to the histological differentiation. The expression of ␤-catenin was found to be heterogeneously distributed not only in various histological grades of the same tumor but also in areas of the same histological grade. p53 and ␤-catenin gene mutations were detected in 1 tumor respectively, both of which were second primary HCCs and also recurred later. The p53 mutation showed the same mutation pattern in heterogeneous subpopulations. ␤-catenin mutation was detected only in the less differentiated lesion but not in the well-differentiated lesion of tumor. In conclusion, our findings suggest that there was histological heterogeneity in small but established HCC, which was accompanied by increased proliferative activity and p53 overexpression. The overexpression of ␤-catenin may be related to the proliferative activity and dedifferentiation of HCC.

Alterations in miRNA expression has direct relationship to MDR in head and neck cancer and may serve as biomolecular targets for reversal of MDR.

The pathologic finding of nerve hypertrophy in children with laryngomalacia provides new evidence to support neurologic dysfunction as the etiologic theory of laryngomalacia.