Well‐defined adaptative and amphiphilic polymer conetworks based on hydrophilic poly(N,N‐dimethylamino‐2‐ethyl methacrylate) (PDMAEMA) and hydrophobic poly(ε‐caprolactone) (PCL) have been prepared by combination of ATRP, ROP, and “Click chemistry.” Telechelic α,ω‐alkyne terminated PCL crosslinker was obtained by ring‐opening polymerization (ROP) of CL in THF at 80 °C initiated by 1,4‐butanediol and catalyzed by tin(II) bis 2‐ethyl hexanoate (Sn(Oct)2), followed by the quantitative esterification of hydroxyl end‐groups by activated 4‐pentynoic acid. In parallel, an azido‐containing PDMAEMA‐based copolymer was obtained in a three‐step strategy involving primarily the copolymerization of DMAEMA with newly synthesized 2‐(2‐azidoethoxy)ethyl methacrylate (AEEMA) monomer. The latter was obtained by nucleophilic substitution of chloride atom from 2‐(2‐chloroethoxy)ethanol by an azide group followed by the esterification reaction of the hydroxyl group with methacrylic anhydride. The copolymerization was carried out in an equivolumic mixture of H2O and isopropanol at r.t. and initiated by a ω‐bromoisobutyryl oligo PEO macroinitiator in the presence of various ligated copper(I)‐based catalysts. In a last step, both polymer precursors were chemically linked by the Huisgen‐1,3‐dipolar cycloaddition in anhydrous THF at r.t. using CuBr complexed by 2,2′‐bipyridine ligand as catalyst. Final material was characterized by the means of DSC and SEM, both attesting of a homogeneous distribution of the PCL crosslinkers and a highly porous structure in this new amphiphilic model conetworks. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4997–5013, 2008
Methotrexate has been in use as an anti-cancer agent for over 60 years. Though inhibition of dihydrofolate reductase is its best known mechanisms of action, its non-dihydrofolate reductase dependent mechanisms disrupt metabolic pathways resulting in a depletion of NAD(P)H and increasing oxidative stress. These mechanisms highlight a novel dependence of cancer cells on their metabolic abnormalities to buffer oxidative stress and chemotherapeutic agents interfere with these cellular abilities. Mitochondria appear to play a significant role in maintaining cancer cell viability and alterations in metabolism seen in cancer cells aid this mitochondrial ability. Further research is needed to understand the effects of other chemotherapeutic agents on these pathways.
BACKGROUND.Sunitinib and sorafenib are small molecules that inhibit the vascular endothelial growth factor and related receptors with substantial clinical activity reported in metastatic renal cell carcinoma (RCC). Cytopenia and macrocytosis have been described in patients treated with these agents.METHODS.A retrospective review of all patients with metastatic RCC who were treated with sunitinib or sorafenib for at least 3 months at the Cleveland Clinic Taussig Cancer Institute was undertaken. Complete blood count (CBC) data including red blood cell indices were recorded at baseline, after 3 months of therapy, and at the end of treatment.RESULTS.A total of 61 patients were treated with sunitinib and 37 patients were treated with sorafenib with available CBC data. In patients treated with sunitinib, the median corpuscular volume (MCV) increased significantly at 3 months compared with baseline (median increase of 5.1 femtoliters [fL]; P < .001) and continued to increase throughout treatment. Patients who developed hypothyroidism had a larger MCV increase at 3 months than patients who remained euthyroid (P = .06), although macrocytosis was observed in patients without hypothyroidism. Ten patients discontinued sunitinib therapy, and the MCV decreased in all patients within 2 to 4 months, without further intervention. Bone marrow analysis of 4 patients revealed a hypocellular bone marrow with trilineage hematopoiesis and no evidence of metastasis. There was no evidence of folate or vitamin B12 deficiency. In contrast to sunitinib, there was no change in the MCV for patients treated with sorafenib.CONCLUSIONS.Macrocytosis was a common occurrence after treatment with sunitinib but not sorafenib in patients with metastatic RCC. Sunitinib‐induced macrocytosis is reversible with drug discontinuation. Cancer 2008. © 2008 American Cancer Society.
OBJECTIVE To describe an association between renal cell carcinoma (RCC) and multiple myeloma (MM) in patients with both disorders, and suggest possible explanations for the association. PATIENTS AND METHODS We retrospectively reviewed the records of patients with MM and RCC at the Cleveland Clinic between 1990 and 2005, and identified 1100 with MM, 2704 with RCC and eight with concomitant MM and RCC. The medical records of these eight patients were reviewed. RESULTS In four of the eight patients, RCC was diagnosed after the MM at 3, 8, 23 and 46 months, respectively; in the remaining four, the RCC was diagnosed before MM by 108, 35, 13 and 1 months, respectively. The number of cases of RCC expected in the present 1100 patients with MM over 15 years was lower than the four recorded (P < 0.001, Fisher’s exact test). Similarly, the number of cases of MM expected in the 2704 patients with RCC was also lower than the four recorded (P < 0.001, Fisher’s exact test). CONCLUSIONS RCC and MM can occur in the same patient at an incidence higher than the expected rate. Possible explanations include genetic abnormalities, environmental exposures or immune‐related mechanisms predisposing to the second malignancy. These findings are particularly relevant in the management of patients with known RCC and lytic bone lesions, or those with known MM and subsequent or concomitant renal masses, especially those involving the right kidney.
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