Vermont Cancer Center

Manchester Center, VT, United States

Vermont Cancer Center

Manchester Center, VT, United States
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Tonato M.,Regina Elena Cancer Institute | Bria E.,Regina Elena Cancer Institute | Ballatori E.,Oncologia Medica | Espersen B.,Aarhus University Hospital | And 7 more authors.
Supportive Care in Cancer | Year: 2011

In this update of our 2005 document, we used an evidence-based approach whenever possible to formulate recommendations, emphasizing the results of controlled trials concerning the best use of antiemetic agents for the prevention of emesis and nausea following anticancer chemotherapies of high emetic risk. A three-drug combination of a 5-hydroxytryptamine type 3 receptor (5-HT3) receptor antagonist, dexamethasone, and aprepitant beginning before chemotherapy and continuing for up to 4 days remains the standard of care. We address issues of dose, schedule, and route of administration of five selective 5-HT3 receptor antagonists. We conclude that, for each of these five drugs, there is a plateau in therapeutic efficacy above which further dose escalation does not improve outcome. In trials designed to prove the equivalence of palonosetron to ondansetron and granisetron, palonosetron proved superior in emesis prevention, while adverse effects were comparable. Furthermore, for all classes of antiemetic agents, a single dose is as effective as multiple doses or a continuous infusion. The oral route is as efficacious as the intravenous route of administration. © 2010 Springer-Verlag.

Long P.M.,University of Vermont | Tighe S.W.,Vermont Cancer Center | Driscoll H.E.,Norwich University | Moffett J.R.,Uniformed Services University of the Health Sciences | And 4 more authors.
PLoS ONE | Year: 2013

Cancer is associated with globally hypoacetylated chromatin and considerable attention has recently been focused on epigenetic therapies. N-acetyl-L-aspartate (NAA), the primary storage form of acetate in the brain, and aspartoacylase (ASPA), the enzyme responsible for NAA catalysis to generate acetate and ultimately acetyl-Coenzyme A for histone acetylation, are reduced in oligodendroglioma. The short chain triglyceride glyceryl triacetate (GTA), which increases histone acetylation and inhibits histone deacetylase expression, has been safely used for acetate supplementation in Canavan disease, a leukodystrophy due to ASPA mutation. We demonstrate that GTA induces cytostatic G0 growth arrest of oligodendroglioma-derived cells in vitro , without affecting normal cells. Sodium acetate, at doses comparable to that generated by complete GTA catalysis, but not glycerol also promoted growth arrest, whereas long chain triglycerides promoted cell growth. To begin to elucidate its mechanism of action, the effects of GTA on ASPA and acetyl-CoA synthetase protein levels and differentiation of established human oligodendroglioma cells (HOG and Hs683) and primary tumor-derived oligodendroglioma cells that exhibit some features of cancer stem cells (grade II OG33 and grade III OG35) relative to an oligodendrocyte progenitor line (Oli-Neu) were examined. The nuclear localization of ASPA and acetyl-CoA synthetase-1 in untreated cells was regulated during the cell cycle. GTA-mediated growth arrest was not associated with apoptosis or differentiation, but increased expression of acetylated proteins. Thus, GTA-mediated acetate supplementation may provide a safe, novel epigenetic therapy to reduce the growth of oligodendroglioma cells without affecting normal neural stem or oligodendrocyte progenitor cell proliferation or differentiation. © 2013 Long et al.

Long P.M.,University of Vermont | Tighe S.W.,Vermont Cancer Center | Driscoll H.E.,Norwich University | Fortner K.A.,University of Vermont | And 2 more authors.
Journal of Cellular Physiology | Year: 2015

Glioblastoma (GBM), the most common primary adult malignant brain tumor, is associated with a poor prognosis due, in part, to tumor recurrence mediated by chemotherapy and radiation resistant glioma stem-like cells (GSCs). The metabolic and epigenetic state of GSCs differs from their non-GSC counterparts, with GSCs exhibiting greater glycolytic metabolism and global hypoacetylation. However, little attention has been focused on the potential use of acetate supplementation as a therapeutic approach. N-acetyl-l-aspartate (NAA), the primary storage form of brain acetate, and aspartoacylase (ASPA), the enzyme responsible for NAA catalysis, are significantly reduced in GBM tumors. We recently demonstrated that NAA supplementation is not an appropriate therapeutic approach since it increases GSC proliferation and pursued an alternative acetate source. The FDA approved food additive Triacetin (glyceryl triacetate, GTA) has been safely used for acetate supplementation therapy in Canavan disease, a leukodystrophy due to ASPA mutation. This study characterized the effects of GTA on the proliferation and differentiation of six primary GBM-derived GSCs relative to established U87 and U251 GBM cell lines, normal human cerebral cortical astrocytes, and murine neural stem cells. GTA reduced proliferation of GSCs greater than established GBM lines. Moreover, GTA reduced growth of the more aggressive mesenchymal GSCs greater than proneural GSCs. Although sodium acetate induced a dose-dependent reduction of GSC growth, it also reduced cell viability. GTA-mediated growth inhibition was not associated with differentiation, but increased protein acetylation. These data suggest that GTA-mediated acetate supplementation is a novel therapeutic strategy to inhibit GSC growth. J. Cell. Physiol. 230: 1929-1943, 2015. © 2015 Wiley Periodicals, Inc.

Alcindor T.,McGill University | Ferri L.E.,McGill University | Marcus V.,McGill University | Andalib A.,McGill University | And 5 more authors.
Medical Oncology | Year: 2013

To determine whether metabolic or pathological response to preoperative chemotherapy can predict the relapse-free survival of gastroesophageal adenocarcinoma patients treated on a perioperative chemotherapy protocol. The prospectively collected data of a recently reported phase II trial of perioperative DCF chemotherapy (docetaxel/cisplatin/5-fluorouracil) were analyzed. Median relapse-free survival (RFS) was compared with the Wilcoxon rank-sum test between responders and non-responders according to defined metabolic (reduction in maximum standard uptake value of at least 35 %) and pathological (greater than 50 % tumor regression or ypN0 status) criteria. A double-sided p value equal or inferior to 0.05 was considered significant. Patients were followed for a median of 807 days (95 % CI: 607-896). RFS was 576 days in metabolic non-responders versus not reached in metabolic responders (p 0.009) and 562 days in ypN+ versus not reached in ypN0 patients (p 0.045). No statistically significant RFS difference was seen between low and high pathologic responders classified according to tumor regression criteria, although a trend was observed in favor of high pathologic responders. Simple metabolic and pathologic criteria used for the assessment of response to the preoperative part of perioperative chemotherapy can help to estimate the outcome of gastroesophageal adenocarcinoma patients. © 2012 Springer Science+Business Media New York.

Caldwell G.B.,University of Vermont | Howe A.K.,University of Vermont | Howe A.K.,Vermont Cancer Center | Nickl C.K.,University of Vermont | And 5 more authors.
Journal of Cellular Biochemistry | Year: 2012

The cyclic-AMP-dependent protein kinase A (PKA) regulates processes such as cell proliferation and migration following activation of growth factor receptor tyrosine kinases (RTKs), yet the signaling mechanisms that link PKA with growth factor receptors remain largely undefined. Here we report that RTKs can directly modulate the function of the catalytic subunit of PKA (PKA-C) through post-translational modification. In vitro kinase assays revealed that both the epidermal growth factor and platelet derived growth factor receptors (EGFR and PDGFR, respectively) tyrosine phosphorylate PKA-C. Mass spectrometry identified tyrosine 330 (Y330) as a receptor-mediated phosphorylation site and mutation of Y330 to phenylalanine (Y330F) all but abolished the RTK-mediated phosphorylation of PKA-C in vitro. Y330 resides within a conserved region at the C-terminal tail of PKA-C that allosterically regulates enzymatic activity. Therefore, the effect of phosphorylation at Y330 on the activity of PKA-C was investigated. The K m for a peptide substrate was markedly decreased when PKA-C subunits were tyrosine phosphorylated by the receptors as compared to un-phosphorylated controls. Importantly, tyrosine-phosphorylated PKA-C subunits were detected in cells stimulated with EGF, PDGF, and Fibroblast growth factor 2 (FGF2) and in fibroblasts undergoing PDGF-mediated chemotaxis. These results demonstrate a direct, functional interaction between RTKs and PKA-C and identify tyrosine phosphorylation as a novel mechanism for regulating PKA activity. Copyright © 2011 Wiley Periodicals, Inc.

Lamba G.,University of Vermont | Lamba G.,Vermont Cancer Center | Zaidi S.K.,Vermont Cancer Center | Zaidi S.K.,University of Vermont | And 6 more authors.
Journal of Cellular Biochemistry | Year: 2014

Acute myeloid leukemia (AML) is an aggressive hematologic cancer that is characterized by accumulation of immature myeloid cells in the blood and bone marrow. The malignant cells in AML have reduced capacity to mature fully, and often exhibit chromosomal abnormalities, defects in cell signaling, and abnormal cell cycle control. Genetic and epigenetic changes are implicated in the onset and progression of AML. While progress has been made in using genetic and epigenetic changes as prognostic features of AML, these findings have not yet been effectively translated into novel treatment strategies. Disappointingly, rates of recurrence in AML remain high and overall survival is poor. Research strategies should focus on developing a comprehensive landscape of genetic and epigenetic changes in individual patients with AML to expand the clinicians' therapeutic armamentarium and to individualize and optimize treatment. © 2014 Wiley Periodicals, Inc.

Weaver D.L.,University of Vermont | Weaver D.L.,Vermont Cancer Center | Weaver D.L.,Fletcher Allen Health Care
Modern Pathology | Year: 2010

Sentinel lymph nodes (SLN) are more likely to contain metastatic breast carcinoma than non-SLNs. The limited number of SLNs compared with an axillary dissection has prompted more comprehensive lymph node analysis increasing detection of micrometastases. National data show that many women previously classified node negative are now classified minimally node positive. As a result, our nodal classification and cancer staging have evolved to recognize the continuum of nodal tumor burden rather than a simplistic dichotomous stratification. It is quite clear that the more sections we evaluate from SLNs the more metastases we identify; however, it is impractical to expect the practicing pathologist to mount, stain, and microscopically examine every section through the SLN paraffin blocks. Despite recommendations from the College of American Pathologists and the American Society of Clinical Oncology, heterogeneity in the approach to SLN evaluation exists. What is needed is adherence to a standardized evaluation protocol. The most important aspect of the sentinel node examination is careful attention to slicing the SLN no thicker than 2.0 mm and correct embedding of the slices to assure we identify all macrometastases larger than 2.0 mm. A single section from blocks prepared in this manner will identify all macrometastases present but smaller metastases will be missed. The prognostic significance of these missed micrometastases is still being evaluated as we await SLN outcome studies. In the context of the new molecular classification of breast cancer, subgroups may be identified where detection of micrometastases has clinical significance. It is critical that both clinicians and pathologists understand there is a random component to micrometastasis distribution within the three-dimensional paraffin tissue blocks. If we ultimately adopt more comprehensive microscopic evaluation of SLNs, the candidate sampling strategies need to be carefully considered in the context of statistically valid sampling strategies. © 2010 USCAP, Inc. All rights reserved.

PubMed | Vermont Cancer Center and University of Vermont
Type: Journal Article | Journal: Journal of clinical oncology : official journal of the American Society of Clinical Oncology | Year: 2017

163 Background: Patients (pts) who fail to achieve pCR after neoadjuvant chemotherapy have a 20% risk of recurrence at two years. Data for effective postsurgical chemotherapy in this population is lacking. LDCM is an all-oral chemotherapy regimen with anti-angiogenic activity and acceptable toxicity in metastatic breast cancer. Aspirin is associated with a lower risk of breast cancer recurrence in retrospective studies and has anti-angiogenic activity. Here we combine LDCM and aspirin for high risk pts with poor response to neoadjuvant chemotherapy.Pts with stage II-III HER-2 negative breast cancer who had residual invasive cancer after neoadjuvant chemotherapy were eligible. Pts completed surgery and radiotherapy prior to enrolment and began study treatment within 180 days of surgery. Pts received four 28-day cycles of LDCM (cyclophosphamide 50 mg po daily, and methotrexate 2.5 mg po twice daily on days 1 and 2 each week ). Aspirin 325 mg daily was added on cycles 3 and 4. Pts were evaluated for the primary endpoint of toxicity and safety every 28 days. Secondary endpoint was 2 year relapse free survival.10 of 13 planned pts were evaluable for toxicity as of May 4, 2013. Pathologic stage ranged from T2N0 to T3N3. 70% of tumors were chemoresistant (stable or upstaged at time of surgery). 60% of pts had hormone receptor positive tumors and received concurrent hormonal therapy. Median age was 59 years (range 38-76). All pts completed 4 cycles of study treatment without dose reduction. There were no grade 3 or 4 related toxicities. Worst hematologic toxicity was grade 2 leukopenia. Worst nonhematologic toxicity was grade 2 fatigue; all other related toxicities were grade 1. 9 pts were evaluable for recurrence and one had recurred at a median followup of 16 months (range 10-26).This antiangiogenic regimen is well tolerated in patients at high risk for recurrence after neoadjuvant chemotherapy, resulting in one recurrence at 16 months median followup, and it may be a candidate for future trials in this setting. Subsequent analyses will include longer term followup and biomarkers for angiogenesis.NCT01612247.

Moukharskaya J.,Vermont Cancer Center | Verschraegen C.,Vermont Cancer Center
Hematology/Oncology Clinics of North America | Year: 2012

Topoisomerase 1 inhibitors cure human cancer xenografts in animal models, more so than most other chemotherapy agents. However, their activity in patients with cancer is modest. Ongoing research is studying the optimal analogues that could reproduce animal data in the cancer population. This article analyzes the clinical research with topoisomerase 1 inhibitors in ovarian cancer. © 2012 Elsevier Inc..

PubMed | Vermont Cancer Center
Type: Journal Article | Journal: Hematology/oncology clinics of North America | Year: 2012

Topoisomerase 1 inhibitors cure human cancer xenografts in animal models, more so than most other chemotherapy agents. However, their activity in patients with cancer is modest. Ongoing research is studying the optimal analogues that could reproduce animal data in the cancer population. This article analyzes the clinical research with topoisomerase 1 inhibitors in ovarian cancer.

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