Advances in the field of boron chemistry have expanded the application of boron from material use to medicine. Boron-based drugs represent a new class of molecules that possess several biomedical applications including use as imaging agents for both optical and nuclear imaging as well as therapeutic agents with anticancer, antiviral, antibacterial, antifungal and other disease-specific activities. For example, bortezomib (Velcade®), the only drug in clinical use with boron as an active element, was approved in 2003 as a proteasome inhibitor for the treatment of multiple myeloma and non-Hodgkin’s lymphoma. Several other boron-based compounds are in various phases of clinical trials, which illustrates the promise of this approach for medicinal chemists working in the area of boron chemistry. It is expected that in the near future, several boron-containing drugs should become available in the market with better efficacy and potency than existing drugs. This article discusses the current status of the development of boron-based compounds as diagnostic and therapeutic agents in humans.

BackgroundDespite recent advances in outlining the mechanisms involved in pancreatic carcinogenesis, precise molecular pathways and cellular lineage specification remains incompletely understood.ResultsWe show here that Cyr61/CCN1 play a critical role in pancreatic carcinogenesis through the induction of EMT and stemness. Cyr61 mRNA and protein were detected in the early precursor lesions and their expression intensified with disease progression. Cyr61/CCN1 expression was also detected in different pancreatic cancer cell lines. The aggressive cell lines, in which the expressions of mesenchymal/stem cell molecular markers are predominant; exhibit more Cyr61/CCN1 expression. Cyr61 expression is exorbitantly higher in cancer stem/tumor initiating Panc-1-side-population (SP) cells. Upon Cyr61/CCN1 silencing, the aggressive behaviors are reduced by obliterating interlinking pathobiological events such as reversing the EMT, blocking the expression of stem-cell-like traits and inhibiting migration. In contrast, addition of Cyr61 protein in culture medium augments EMT and stemness features in relatively less aggressive BxPC3 pancreatic cancer cells. Using a xenograft model we demonstrated that cyr61/CCN1 silencing in Panc-1-SP cells reverses the stemness features and tumor initiating potency of these cells. Moreover, our results imply a miRNA-based mechanism for the regulation of aggressive behaviors of pancreatic cancer cells by Cyr61/CCN1.ConclusionsIn conclusion, the discovery of the involvement of Cyr61/CCN1 in pancreatic carcinogenesis may represent an important marker for PDAC and suggests Cyr61/CCN1 can be a potential cancer therapeutic target.

SummaryWe assessed the association of postmenopausal serum levels of oestrogens and sex hormone-binding globulin (SHBG) with endometrial cancer risk in a case-control study nested within the NYU Women's Health Study cohort. Among 7054 women postmenopausal at enrolment, 57 cases of endometrial cancer were diagnosed a median of 5.5 years after blood donation. Each case was compared to 4 controls matched on age, menopausal status at enrolment, and serum storage duration. Endometrial cancer risk increased with higher levels of oestradiol (odds ratio = 2.4 in highest vs lowest tertile, P for trend = 0.02), percent free oestradiol (OR = 3.5, P < 0.001), and oestrone (OR = 3.9, P < 0.001). Risk decreased with higher levels of percent SHBG-bound oestradiol (OR = 0.43, P = 0.03) and SHBG (OR = 0.39, P = 0.01). Trends remained in the same directions after adjusting for height and body mass index. A positive association of body mass index with risk was substantially reduced after adjusting for oestrone level. Our results indicate that risk of endometrial cancer increases with increasing postmenopausal oestrogen levels but do not provide strong support for a role of body mass index independent of its effect on oestrogen levels.

Crocetin, a carotenoid compound derived from saffron, has long been used as a traditional ancient medicine against different human diseases including cancer. The aim of the series of experiments was to systematically determine whether crocetin significantly affects pancreatic cancer growth both in vitro and/or in vivo. For the in vitro studies, first, MIA-PaCa-2 cells were treated with crocetin and in these sets of experiments, a proliferation assay using H 3 -thymidine incorporation and flow cytometric analysis suggested that crocetin inhibited proliferation. Next, cell cycle proteins were investigated. Cdc-2, Cdc-25C, Cyclin-B1, and epidermal growth factor receptor were altered significantly by crocetin. To further confirm the findings of inhibition of proliferation, H 3 -thymidine incorporation in BxPC-3, Capan-1, and ASPC-1 pancreatic cancer cells was also significantly inhibited by crocetin treatment. For the in vivo studies, MIA-PaCa-2 as highly aggressive cells than other pancreatic cancer cells used in this study were injected into the right hind leg of the athymic nude mice and crocetin was given orally after the development of a palpable tumor. The in vivo results showed significant regression in tumor growth with inhibition of proliferation as determined by proliferating cell nuclear antigen and epidermal growth factor receptor expression in the crocetin-treated animals compared with the controls. Both the in vitro pancreatic cancer cells and in vivo athymic nude mice tumor, apoptosis was significantly stimulated as indicated by Bax/Bcl-2 ratio. This study indicates that crocetin has a significant antitumorigenic effect in both in vitro and in vivo on pancreatic cancer. [Mol Cancer Ther 2009;8(2):315 -23]

Motility of vascular smooth muscle cells (SMCs) is an essential step for both normal and pathologic angiogenesis. We report here that breast tumor cells, such as MCF-7 and MDA-MB-231, can modulate this SMC migration. We present evidence that the tumor cell-derived platelet-derived growth factor (PDGF) is the key regulator of vascular SMCs motility induced by breast cancer cells. PDGF significantly upregulates neuropilin-1 (NRP-1) mRNA expression and protein production in aortic smooth muscle cells (AOSMCs) and depletion of NRP-1 production by AOSMCs with specific short hairpin RNA (shRNA) prevents the PDGF-dependent migration of vascular SMCs. Moreover, we demonstrate that PDGF physically interacts with NRP-1. We propose that tumor-derived PDGF and NRP-1 of AOSMCs function as a relay system that promotes motility of vascular SMCs.

Up-regulation of the dolichol pathway, a "hallmark" of asparagine-linked protein glycosylation, enhances angiogenesis in vitro. The dynamic relationship between these two processes is now evaluated with tunicamycin. Capillary endothelial cells treated with tunicamycin were growth inhibited and could not be reversed with exogenous VEGF(165). Inhibition of angiogenesis is supported by down-regulation of (i) phosphorylated VEGFR1 and VEGFR2 receptors; (ii) VEGF(165)-specific phosphotyrosine kinase activity; and (iii) Matrigel(TM) invasion and chemotaxis. In vivo, tunicamycin prevented the vessel development in Matrigel(TM) implants in athymic Balb/c (nu/nu) mice. Immunohistochemical analysis of CD34 (p < 0.001) and CD144 (p < 0.001) exhibited reduced vascularization. A 3.8-fold increased expression of TSP-1, an endogenous angiogenesis inhibitor in Matrigel(TM) implants correlated with that in tunicamycin (32 h)-treated capillary endothelial cells. Intravenous injection of tunicamycin (0.5 mg/kg to 1.0 mg/kg) per week slowed down a double negative (MDA-MB-435) grade III breast adenocarcinoma growth by ∼50-60% in 3 weeks. Histopathological analysis of the paraffin sections indicated significant reduction in vessel size, the microvascular density and tumor mitotic index. Ki-67 and VEGF expression in tumor tissue were also reduced. A significant reduction of N-glycan expression in tumor microvessel was also observed. High expression of GRP-78 in CD144-positive cells supported unfolded protein response-mediated ER stress in tumor microvasculature. ∼65% reduction of a triple negative (MDA-MB-231) breast tumor xenograft in 1 week with tunicamycin (0.25 mg/kg) given orally and the absence of systemic and/or organ failure strongly supported tunicamycin's potential for a powerful glycotherapeutic treatment of breast cancer in the clinic.

Endoscopic and histologic features of BE at initial diagnosis are predictive of index HGD and cancer as well as with risk of BE progression.

The expression and distribution of neuropilin-1 (NRP-1) was examined in the samples of normal human breast tissues and in non-neoplastic and neoplastic areas of breast tissue removed for carcinoma using RT-PCR as well as conventional and tissue microarrays immunohistochemical analyses. The NRP-1 mRNA expression was significantly higher in neoplastic tissues as compared to normal breast samples. Immunohistochemically, the myoepithelial cells of the mammary ducts and lobules display positive reactions for NRP-1, whereas the inner ductal and lobular epithelial cell layers failed to react. The myoepithelial cells of ducts and lobules in both neoplastic and non-neoplastic tissue specimens displayed a stronger positive reaction for NRP-1 than those in the normal breast. A positive reaction for NRP-1, but with a gradual reduction in intensity, was observed in the myoepithelial cells of ducts with atypical epithelial hyperplasia and ductal carcinoma in situ (DCIS). The reaction was undetected or minimally detected in the areas of invasive carcinoma. NRP-1 positive immunolabeling was also localized in the vascular smooth muscle cells and in some endothelial cells of the blood vessels in normal, non-neoplastic and neoplastic breast tissue samples. In areas of breast carcinoma, NRP-1 immunolabeling was more prominent in both vascular smooth muscle cells and in some endothelial cells than in similar cells in normal breast. The specificity of the newly developed antibody for NRP-1 was confirmed by in situ hybridization with DIG-labeled PCR generated probe. These results suggest that NRP-1 may be a multiple function protein in human breast and may be involved in the induction of local invasiveness of neoplasia and angiogenesis and have direct relevance to the progression of breast cancer.