Although a primary route of breast cancer metastasis is believed to be via lymphatics, the molecular factors involved are poorly understood. We hypothesized that one such factor may be the integrin-binding protein osteopontin (OPN), and we investigated this clinically and experimentally. In breast cancer patients undergoing sentinel lymph node biopsy, OPN levels were significantly higher in lymph node metastases than in the primary tumor (P < 0.001). To test the functional contribution of OPN to lymphatic metastasis and to determine whether the RGD (Arg-Gly-Asp) integrin-binding sequence of OPN is important for this process, we transfected wild-type OPN or mutant OPN (lacking the RGD sequence) into MDA-MB-468 human breast cancer cells. In vitro, cells overexpressing OPN demonstrated increased anchorage-independent growth in soft agar (P = 0.001) and increased RGD-dependent adhesion (P = 0.045). Following mammary fat pad injection of nude mice, cells overexpressing OPN showed increased lymphovascular invasion, lymph node metastases, and lung micrometastases at earlier time points (P = 0.024). Loss of the RGD region partially abrogated this effect in the lymphatics (P = 0.038). These novel findings indicate that OPN is a key molecular player involved in lymphatic metastasis of breast cancer, potentially by affecting RGD-mediated adhesive interactions and by enhancing the establishment/persistence of tumor cells in the lymphatics.

The scope and limitations of the alkylation of [closo-B12(OH)12]2- using a series of fourteen alkyl and aralkyl halides and two p-toluenesulfonic acid esters in the presence of N,N-diisopropylethylamine have been investigated. The dodecaalkoxy-closo-dodecaborate products, [closo-B12(OR)12]2-, and their hypercloso two-electron oxidation products have been explored. The species [closo-B12(OR)12]2- containing 26 cage-bonding electrons may undergo two reversible, sequential, one-electron oxidation processes, producing a 25-electron radical anion and a 24-electron neutral species. Several oxidizing reagents were investigated for the chemical oxidation of [closo-B12(OR)12]2- and [hypercloso-B12(OR)12]- to [hypercloso-B12(OR)12]. Both FeCl3.6H2O and K3Fe(CN)6 in 90/5/5 ethanol/acetonitrile/H2O were found to be the reagents of choice. The reverse reaction leading from the neutral species to the radical anion and subsequently to the dianion was achieved using sodium borohydride in ethanol. A variety of alkoxyl derivatives have been synthesized by heating the reactants for extended periods of time in acetonitrile at the reflux temperature. The use of elevated reaction temperatures attained by employing moderate argon pressure (autoclave) over the reaction mixture led to drastic reductions in reaction times and increased efficiency. X-ray diffraction studies of substituted dodecabenzyl ether derivatives proved that 2(2-) has approximate Ih symmetry while hypercloso-2, -3, -9, -11, -12, and -13 have approximate D3d point group symmetry due to Jahn-Teller distortion from Ih.

Boron neutron capture therapy (BNCT) has undergone dramatic developments since its inception by Locher in 1936 and the development of nuclear energy during World War II. The ensuing Cold War spawned the entirely new field of polyhedral borane chemistry, rapid advances in nuclear reactor technology and a corresponding increase in the number to reactors potentially available for BNCT. This effort has been largely oriented toward the eradication of glioblastoma multiforme (GBM) and melanoma with reduced interest in other types of malignancies. The design and synthesis of boron-10 target compounds needed for BNCT was not channeled to those types of compounds specifically required for GBM or melanoma. Consequently, a number of potentially useful boron agents are known which have not been biologically evaluated beyond a cursory examination and only three boron-10 enriched target species are approved for human use following their Investigational New Drug classification by the US Food and Drug Administration; BSH, BPA and GB-10. All ongoing clinical trials with GBM and melanoma are necessarily conducted with one of these three species and most often with BPA. The further development of BNCT is presently stalled by the absence of strong support for advanced compound evaluation and compound discovery driven by recent advances in biology and chemistry. A rigorous demonstration of BNCT efficacy surpassing that of currently available protocols has yet to be achieved. This article discusses the past history of compound development, contemporary problems such as compound classification and those problems which impede future advances. The latter include means for biological evaluation of new (and existing) boron target candidates at all stages of their development and the large-scale synthesis of boron target species for clinical trials and beyond. The future of BNCT is bright if latitude is given to the choice of clinical disease to be treated and if a recognized study demonstrating improved efficacy is completed. Eventually, BNCT in some form will be commercialized.

Twelve of one, a dozen of the other: Synthetic pseudometallic molecules were prepared by fully substituting the [B12H12]2− ion with 12 alkoxy groups. Reversible redox reactions reveal substituent‐dependent potentials varying over 1.2 V (see picture) which were characterized and correlated using Hammett and QSAR linear free‐energy relationships.

Three men and 2 women with ages ranging from 37 to 70 years, clinically and histologically confirmed solitary, palpable metastatic cancers to the thyroid (SMCT) and preoperative cytologic investigation of their thyroid lesions by fine-needle aspiration (FNA), were reviewed. Four patients were known to have a solid cancer treated by radical surgery 1 to 4 years prior [1 bronchogenic squamous cell carcinoma, 1 parotid adenoid cystic carcinoma, 1 renal cell carcinoma (RCC) and 1 cutaneous melanoma], and 1 patient had no past history of cancer. Direct smears prepared from the patients' thyroid FNAs were fixed in 95% ethanol and stained with the Papanicolaou method. In 3 cases, immunostaining of the aspirated tumor cells with thyroglobulin antibody was performed, and in 1 case an aspiration smear was stained with commercial HMB-45 antibody. A correct cytodiagnosis of metastatic cancer to the thyroid was made in all 5 cases. In 1 patient the thyroid FNA revealed a metastatic RCC that led to the discovery of a clinically occult RCC. All 5 patients died of metastatic disease 27 to 40 months after surgical resection of their SMCTs.

Das Dutzend voll gemacht: Synthetische pseudometallische Moleküle entstanden bei der vollständigen Substitution des [B12H12]2−‐Ions mit 12 Alkoxygruppen. Reversible Redoxreaktionen ergeben substituentenabhängige Potentiale über einen Bereich von 1.2 V (siehe Bild), die charakterisiert und mithilfe von Hammett‐ und QSAR‐Lineare‐freie‐Energie‐Beziehungen korreliert wurden.

Herein we report the use of carboranes to significantly increase the potency of small molecule inhibitors of nicotinamide phosphoribosyltranferase (Nampt), an enzyme that is central to metabolism and cell survival. We compare the inclusion of carborane with other similarly sized substituents and demonstrate that, compared with their purely organic counterparts, these molecules exhibit up to 10-fold greater antiproliferative activity against cancer cells in vitro and a 100-fold increase in Nampt inhibition.

A family of η 5 -CpFe(CO) 2 -substituted closo-carboranes was synthesized and characterized, including cyclic voltammetry measurements. Like the previously reported bimetallic compound 1,12-[η 5 -CpFe(CO) 2 ] 2 -1,12-C 2 B 10 H 10 (8), 1,10-[η 5 -CpFe(CO) 2 ] 2 -1,10-C 2 B 8 H 8 (9) produces two dissimilar and irreversible one-electron oxidations within the same range, suggesting that it also exhibits through-cage electronic communication between iron centers. Structures determined by X-ray diffraction studies are reported for 1-[η 5 -CpFe(PPh 3 )(CO)]-1,12-C 2 B 10 H 11 (5), 1,12-[η 5 -CpFe(CO) 2 ] 2 -1,12-C 2 B 10 H 10 (8), and 1,10-[η 5 -CpFe(CO) 2 ] 2 -1,10-C 2 B 8 H 8 (9).