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Carmelo Blanquicett

Publications and source records attributed to Carmelo Blanquicett.

6 recordsLinked to original sources
PubMed2006

A rapid and inexpensive method for anticipating severe toxicity to fluorouracil and fluorouracil-based chemotherapy.

Dihydropyrimidine dehydrogenase (DPD) deficiency leads to dramatic overexposure to fluorouracil (5-FU), resulting in a potentially lethal outcome in patients treated with standard doses. The aim of this study was to validate, in a routine clinical setting, a simple and rapid method to determine the DPD status in a subset of cancer patients, all presenting with life-threatening toxicities following 5-FU or capecitabine intake. In this study, 80 out of 615 patients (13%) suffered severe toxicities, including 5 lethal ones (0.8%), during or after chemotherapy with a fluoropyrimidine drug. Patients with severe toxicities were treated with 5-FU (76 patients) or capecitabine-containing protocols (4 patients). Simplified uracil to di-hydrouracil (U/UH2) ratio determination in plasma was retrospectively performed in these 80 patients, as a surrogate marker of DPD activity. When possible, 5-FU Css determination was performed, and screenings for the canonical IVS14+1G>A mutation were systematically carried out. Comparison of the U/UH2 ratios with a reference, non-toxic population, showed abnormal values suggesting impaired DPD activity in 57 out of the 80 toxic patients (71%) included in this study, and in 4 out of 5 patients (80%) with a fatal outcome. Similarly, drug exposures up to 15 times higher than the range observed in the non-toxic population were also observed. Importantly, no IVS14+1G>A mutation was found in these patients, including those displaying the most severe or lethal toxicities. These data warrant systematic detection of DPD-deficient patients prior to fluoropyrimidine administration, including when oral capecitabine (Xeloda) is scheduled. Finally, the simplified methodology presented here proved to be a low cost and rapid way to identify routinely patients at risk of toxicity with 5-FU or capecitabine.

Adult↗
PubMed2006

Multiple gene expression analyses in paraffin-embedded tissues by TaqMan low-density array: Application to hedgehog and Wnt pathway analysis in ovarian endometrioid adenocarcinoma.

Recent studies have shown the hedgehog and Wnt families of signaling proteins to be associated with tumor initiation, growth, and survival. However, these pathways remain unexplored in ovarian endometrioid adenocarcinoma (OEA). Here, we describe a novel TaqMan low-density array to examine the expression of 26 and 20 genes in the hedgehog and Wnt pathways, respectively, in six matched snap-frozen and formalin-fixed, paraffin-embedded (FPE) OEA specimens. Expression values were normalized to uninvolved ovarian epithelium. Gene expression in matched frozen and FPE tissues demonstrated significant concordance (r = 0.92, P < 0.0001). However, comparison of amplified and unamplified RNA from frozen OEA tissues revealed an altered molecular profile in amplified RNA. Amplification of RNA from FPE tissues was not successful. The expression of Desert hedgehog (DHH), Indian hedgehog (IHH), Hedge-hog interacting protein (HHIP), Wnt10B, Wnt9B, and Wnt inhibitory factor (WIF1) were tumor-specific with no detectable expression in normal ovarian epithelium. In addition, several genes were significantly (P < 0.025) down-regulated in OEA, including cyclin E2, Porcupine, c-Myc, and Axin 2 (4.8-, 3.6-, 2.9-, and 1.9-fold, respectively). TaqMan low-density array provides an effective multivariate technique for examining gene expression in RNA isolated from either snap-frozen or archival FPE tissues and can identify tumor-specific genes, possibly leading to novel treatments.

Animals↗
PubMed2005

Antitumor efficacy of capecitabine and celecoxib in irradiated and lead-shielded, contralateral human BxPC-3 pancreatic cancer xenografts: clinical implications of abscopal effects.

PURPOSE: X-ray therapy (XRT) remains one of the major modalities used to treat patients diagnosed with locally advanced pancreatic adenocarcinoma. However, the effect of XRT on metastatic tumors outside the field of irradiation (abscopal effect) remains largely unknown. In the current study, we examined the effect of XRT alone and in combination with capecitabine and/or celecoxib in both irradiated and lead-shielded contralateral BxPC-3 pancreatic cancer xenografts. This chemoradiation regimen was chosen based on our molecular analysis of pancreatic adenocarcinoma. EXPERIMENTAL DESIGN: Athymic mice were injected bilaterally with BxPC-3 cells and treatment was initiated 28 days postimplant. During XRT (2 Gy for 5 consecutive days, administered on days 0 and 24), one flank was irradiated whereas the rest of the body (including the contralateral tumor) was lead shielded. Capecitabine (350 mg/kg) was administered on days 0 to 13 and 24 to 37. Celecoxib was initiated in the diet at 100 ppm (equivalent to 20 mg/kg/d p.o.) and administered throughout the study. RESULTS: In irradiated xenografts, capecitabine and XRT showed synergistic anitiumor efficacy (P=0.008), which was further improved with the addition of celecoxib (P<0.001). In contralateral shielded xenografts, abscopal effects were observed. Whereas monotherapy with XRT showed significant reduction in tumor area in irradiated xenografts, growth was promoted by 23% (P<0.001) in contralateral lead-shielded tumors in the same animals relative to untreated tumors. Interestingly, synergistic antiproliferative efficacy occurred in these contralateral tumors when capecitabine was administered (P<0.001), despite being outside the irradiated field. The addition of celecoxib further inhibited tumor growth (P<0.001). This trimodal combination most effectively stabilized disease in both shielded and irradiated tumors; however, tumor eradication was not observed. There were no significant changes in thymidine phosphorylase, dihydropyrimidine dehydrogenase, or cyclooxygenase-2 mRNA levels in irradiated or lead-shielded tumors, suggesting that efficacy cannot be predicted solely from these previously identified indicators of response. Immunohistochemistry examining the proliferation marker Ki-67 showed concordance with tumor response in both irradiated and contralateral shielded xenografts. CONCLUSIONS: These results have implications in the rational design of treatment paradigms for pancreatic cancer where metastatic disease remains the primary cause of patient morbidity and abscopal effects in tumors outside the field of irradiation may affect tumor response.

5'-Nucleotidase↗
PubMed2004

Increased peptidylarginine deiminase type II in hypoxic astrocytes.

Peptidylarginine deiminase type II (PAD 2) is the primary enzyme responsible for conversion of protein bound arginine to citrulline in the central nervous system. Evidence suggests that glial fibrillary acidic protein (GFAP), the main intermediate filament in astrocytes, is deiminated, but not much is known regarding factors that control this enzymatic reaction. The present study demonstrated that PAD 2 activity (as determined by Western blot analysis of citrullinated GFAP isoforms) was increased in human cultured astrocytes by hypoxic conditions. PAD 2 mRNA increased markedly during the first 2h of hypoxia, but using a single chain antibody against human PAD 2 produced from the ETH-2 phage library, it took approximately 8h of hypoxia to see marked increases in PAD 2 protein. Thus, this is the first report to demonstrate a measurable response in the amounts of PAD 2 mRNA, protein and activity in human astrocytes by prolonged hypoxic exposure.

Adaptation, Physiological↗
PubMed2002

Induction of thymidine phosphorylase in both irradiated and shielded, contralateral human U87MG glioma xenografts: implications for a dual modality treatment using capecitabine and irradiation.

In the United States, tumors of the central nervous system remain the third leading cancer-related cause of death in young adults with a median survival time of < 1 year. A recent case study suggested that Capecitabine (a novel, fluoropyrimidine prodrug) may be effective in the treatment of brain metastases. Pharmacogenomic studies have correlated the antitumor response to Capecitabine with the expression of the drug metabolizing enzymes thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD). In the current study, we examined TP and DPD expression in normal human brain tissues and in glioblastoma multiforme, the most common and malignant type of brain tumor. Because previous reports suggest a tumor necrosis factor (TNF)-alpha-mediated increase in TP expression after irradiation (a current standard of care for glioblastoma multiforme), we also examined the effect of irradiation on the expression of TP, DPD, and TNF-alpha in both irradiated and lead-shielded contralateral U87MG glioma xenografts within the same animal. Expression levels were determined using real-time quantitative PCR as described previously. Results demonstrate an approximately 70-fold increase in TP mRNA levels 4 days after irradiation, relative to initial control levels. Interestingly, TP mRNA in the lead-shielded tumors (contralateral to irradiated tumors) increased approximately 60-fold by day 10 relative to initial control levels. Elevated TP levels were sustained for 20 days in irradiated xenografts but began to decrease after 15 days in the shielded/contralateral tumors, returning to baseline by 20 days. TP mRNA levels in normal mouse liver were unaltered, suggesting a tumor-associated effect. TNF-alpha mRNA levels did not increase after irradiation; therefore, mRNA expression of 11 additional cytokines [interleukin (IL)-1 alpha, IL-1 beta, IL-2, IL-4, IL-5, IL-8, IL-10, IL-12p35, IL-12p40, IL-15, and IFN-gamma] in both the irradiated and shielded xenografts was quantitated. Results demonstrated increased levels of IFN-gamma, IL-10, and IL-1 alpha by 6.3-, 3.7-, and 1.6-fold, respectively, in irradiated tumors only. DPD mRNA levels did not change after irradiation. The tumor-associated induction of TP in irradiated and lead-shielded tumors within the same animal may have significant implications for the combined modality treatment of cancer patients with Capecitabine in conjunction with radiotherapy and may apply to the treatment of distant tumors and or metastatic disease.

Animals↗