Early diagnosis of anastomotic leakage after colorectal surgery by the Dutch leakage score, serum procalcitonin and serum C-reactive protein: study protocol of a prospective multicentre observational study by the Italian ColoRectal Anastomotic Leakage (iC.

BACKGROUND: Anastomotic leakage (AL) is a dreaded major complication after colorectal surgery. There is no uniform definition of anastomotic dehiscence and leak. Over the years many risk factors have been identified (distance of anastomosis from anal verge, gender, BMI, ASA score) but none of these allows an early diagnosis of AL. The DUtch LeaKage (DULK) score, C reactive protein (CRP) and procalcitonin (PCT) have been identified as early predictors for anastomotic leakage starting from postoperative day (POD) 2-3. The study was designed to prospectively evaluate AL rates after colorectal resections, in order to give a definite answer to the need for clear risk factors, and testing the diagnostic yeld of DULK score and of laboratory markers. Methods and analysis. A prospective enrollment for all patients undergoing elective colorectal surgery with anastomosis carried out from September 2017 to September 2018 in 19 Italian surgical centers. OUTCOME MEASURES: preoperative risk factors of anastomotic leakage; operative parameters; leukocyte count, serum CRP, serum PCT and DULK score assessment on POD 2 and 3. Primary endpoint is AL; secondary endpoints are minor and major complications according to Clavien-Dindo classification; morbidity and mortality rates; readmission and reoperation rates, length of postoperative hospital stay (Retrospectively registered at ClinicalTrials.gov Identifier: NCT03560180, on June 18, 2018). Ethics. The ethics committee of the "Comitato Etico Regionale delle Marche - C.E.R.M." reviewed and approved this study protocol on September 7, 2017 (protocol no. 2017-0244-AS). All the participating centers submitted the protocol and obtained authorization from the local Institutional Review Board.

Single nucleotide polymorphism in the neuroplastin locus associates with cortical thickness and intellectual ability in adolescents.

Despite the recognition that cortical thickness is heritable and correlates with intellectual ability in children and adolescents, the genes contributing to individual differences in these traits remain unknown. We conducted a large-scale association study in 1583 adolescents to identify genes affecting cortical thickness. Single-nucleotide polymorphisms (SNPs; n=54,837) within genes whose expression changed between stages of growth and differentiation of a human neural stem cell line were selected for association analyses with average cortical thickness. We identified a variant, rs7171755, associating with thinner cortex in the left hemisphere (P=1.12 × 10(-)(7)), particularly in the frontal and temporal lobes. Localized effects of this SNP on cortical thickness differently affected verbal and nonverbal intellectual abilities. The rs7171755 polymorphism acted in cis to affect expression in the human brain of the synaptic cell adhesion glycoprotein-encoding gene NPTN. We also found that cortical thickness and NPTN expression were on average higher in the right hemisphere, suggesting that asymmetric NPTN expression may render the left hemisphere more sensitive to the effects of NPTN mutations, accounting for the lateralized effect of rs7171755 found in our study. Altogether, our findings support a potential role for regional synaptic dysfunctions in forms of intellectual deficits.

Aprepitant versus metoclopramide, both combined with dexamethasone, for the prevention of cisplatin-induced delayed emesis: a randomized, double-blind study.

BACKGROUND: A combination of aprepitant, a 5-HT3 receptor antagonist (r.a.), and dexamethasone is recommended for the prophylaxis of cisplatin-induced nausea and vomiting in the acute phase, and aprepitant + dexamethasone (A + D) in the delayed phase. The aim of this study was to verify if A + D is superior to metoclopramide plus dexamethasone (M + D) in preventing delayed emesis in cancer patients receiving the same prophylaxis for acute emesis. PATIENTS AND METHODS: A randomized double-blind study comparing A + D versus M + D was completed in previously untreated cancer patients. Before chemotherapy, all patients were treated with intravenous palonosetron 0.25 mg and dexamethasone 12 mg, and oral aprepitant 125 mg. On day 2-4, patients randomly received oral dexamethasone 8 mg plus aprepitant 80 mg once daily (days 2-3) or metoclopramide 20 mg four times daily plus dexamethasone 8 mg bid. Primary endpoint was rate of complete response (no vomiting, no rescue treatment) in day 2-5 after chemotherapy. RESULTS: Due to difficulty in the accrual of patients, 303 of the 480 planned patients were enrolled, 284 were fully evaluable, 147 receiving A + D, 137 M + D. Day 1 results were similar in both arms. On day 2-5, complete response rate was not significantly different (80.3% with A + D versus 82.5% with M + D, P < 0.38, respectively), and all secondary endpoints were also similar (complete protection, total control, no vomiting, no nausea, and score of Functional Living Index-Emesis; P < 0.24). Adverse events incidence was not significantly different between the two treatments. CONCLUSIONS: In cancer patients submitted to cisplatin-based chemotherapy, receiving the same antiemetic prophylaxis for acute emesis, A + D is not superior to M + D in preventing delayed emesis, and both treatments present similar toxicity. CLINICALTRIALSGOV NUMBER: NCT00869310.

Evaluation of colon cancer prognostic factors by CT and MRI: an up-to-date review.

Colorectal cancer (CRC) is a significant global health concern. Prognostication of CRC traditionally relies on the Union for International Cancer Control (UICC) and American Joint Committee on Cancer (AJCC) TNM staging classifications, yet clinical outcomes often vary independently of stage. Despite similarities, rectal and colon cancers are distinct in their diagnostic methodologies and treatments, with MRI and CT scans primarily used for staging rectal and colon cancers, respectively. This paper examines the challenges in accurately assessing prognostic factors of colon cancer such as primary tumor extramural extension, retroperitoneal surgical margin (RSM) involvement, extramural vessel invasion (EMVI), and lymph node metastases through preoperative CT and MRI. It highlights the importance of these factors in risk stratification, treatment decisions, and surgical planning for colon cancer patients. Advancements in imaging techniques are crucial for improving clinical management and optimizing patient outcomes, underscoring the necessity for ongoing research to refine diagnostic methods and incorporate novel findings into practice.

Partial cloning of CB1 cDNA and CB1 mRNA changes in stress responses in the Solea solea.

Endogenous cannabinoids, through the CB1 receptor, are involved in the control of several functions including stress responses. The aim of this study was to investigate the presence of cannabinoid receptor CB1 in the sole ovary by partial cloning of brain CB1 cDNA; in a stress paradigm of disturbance by handling, which consisted in catching, netting and hand-sorting, changes of CB1 mRNA were related with those of proopiomelanocortin (POMC) mRNA; the trend and timing of stress responses and adaptation were monitored by measuring plasma cortisol levels. We characterized two forms of CB1-like receptor, termed CB1A and CB1B. The two sole CB1 (both 799bp) share 76% identity in their cDNAs, and the deduced amino acid sequences are 80% identical. The handling stress induced a sustained increase in plasma cortisol levels 1h after the handling began and decreased to low levels 12h after initiation of handling, showing the same trend of ovarian POMC mRNA expression. In addition, while CB1A mRNA did not show any significant changes during handling stress, significantly lower levels of CB1B mRNA were found in stressed fish 1h after the beginning of handling, with CB1 expression increased 24h after stress induction, both in the ovary and brain. It can be concluded that endocannabinoid system is involved in the modulation of adaptive responses to environmental conditions.

Variation of the genetic expression pattern after exposure to estradiol-17beta and 4-nonylphenol in male zebrafish (Danio rerio).

There is much concern about the increasing presence in the environment of synthetic chemicals that are able to disrupt the endocrine system. Among these compounds, 4-nonylphenol (4-NP) is one of the most studied xenoestrogens, due to its widespread accumulation in water sediment and consequent presence in fatty acid of aquatic organisms. Here, we have used a zebrafish microarray representing 16,399 genes to study the effects of 4-NP and estradiol-17beta (E2) in adult male zebrafish in order to elucidate the mechanism of action of 4-NP compared with that of E2. The microarray results showed that both 4-NP and E2 induced a strong expression of vitellogenin (VTG), the sex related precursor of the yolk proteins in oviparous vertebrates. Both treatments induced elevated protein turnover upregulating genes involved in proteolysis and those that are constituents of the ribosome. Many genes regulated by 4-NP and E2 are involved in energy metabolism, oxidative stress defense mechanisms, xenobiotic metabolism, and lipid metabolism. A different pattern of expression in the two treatments was found for genes involved in oxidative stress, since E2 seems to induce the mechanism of detoxification, while 4-NP seems to inhibit this protective mechanism of the cell. Overall, these findings demonstrate that the microarray approach can contribute significantly to the understanding of expression patterns induced by E2 and 4-NP in male zebrafish. The results also demonstrate that 4-NP is able to act through an alternative pattern to that of estradiol-17beta, modulating the expression of the same genes in a different manner.

Acid pre-treatment of sewage anaerobic sludge to increase hydrogen producing bacteria HPB: effectiveness and reproducibility.

The present study is aimed to test the effectiveness and the reproducibility of the acid pre-treatment of sewage sludge to suppress the methanogenic bacteria activity, in order to increase the hydrogen forming bacteria activity, mainly Clostridium species. The treated sludge has been tested on glucose reach medium under mesophilic conditions (35 degrees C), in batch mode to quantify the biological fermentative hydrogen production. In the whole series of experiments, the main components of biogas are hydrogen (52-60%) and carbon dioxide (40-48%); no methane and hydrogen sulphide were present in it. The rate of biogas production reached a maximum of 75 ml/lh. An overall mean hydrogen conversion efficiency was 11.20% on the assumption of maximum of 3 mol H2/mol glucose. Clostridium spp. multiplied ten times after 10 h of fermentation and over that thousand times at the end of fermentation.

Cholecystokinin A and B receptors are differentially expressed in normal pancreas and pancreatic adenocarcinoma.

Cholecystokinin (CCK) plays an important role in pancreatic carcinogenesis. While human CCK-A and -B receptors have been fully characterized, their relative roles in human pancreatic adenocarcinoma remain unclear. Thus, expression of CCK-A and -B receptors in normal human pancreas, pancreatic adenocarcinomas, and other human extrapancreatic tissues and malignancies was examined, using reverse transcription followed by the polymerase chain reaction (RT-PCR). mRNA isolated from 15 normal pancreas specimens, 22 pancreatic adenocarcinomas, and 58 extrapancreatic tissues and tumors was subjected to RT-PCR using primers specific for human CCK-A and -B receptors. Expression of CCK-B receptors was detected in all tissues arising from pancreas and in most extrapancreatic tissues and tumors. In contrast, CCK-A receptors exhibited a more selective pattern of expression in gall bladder, intestine, brain, ovary, spleen, and thymus. Of significance, CCK-A receptors were expressed selectively in all pancreatic adenocarcinomas, but not in any normal pancreas specimens. In situ hybridization, using receptor-specific riboprobes, localized CCK-A receptor expression to ductal cells, the presumed origin of most human pancreatic adenocarcinomas. Southern blot analysis revealed no evidence of CCK-A receptor gene amplification or rearrangement in pancreatic adenocarcinomas. Because of its selective expression, the CCK-A receptor may serve as selective biomarker for pancreatic adenocarcinoma.

Quantitative estimation of uncertainty in human risk analysis.

This paper is aimed to candidate the use of an ISO standard procedure (Guide to the Expression of Uncertainty in Measurement, GUM) for quantitative evaluation of uncertainty in Human Risk estimation under chronic exposure to a hazardous chemical compound. Risk was evaluated by using the usual methodologies: the deterministic reasonable maximum exposure (RME) and the statistical Monte Carlo method; in both cases the procedures to evaluate the uncertainty on risk values are detailed. The paper put in evidence that the procedure is able to single out the variables that contribute mostly to the uncertainty. The obtained results show that the application of GUM procedure is easy and straightforward to estimate the uncertainty value on the results of risk estimation. The procedure is applied to a real case concerning the ingestion of milk contaminated by dioxins in a northern part of Italy; the risk value resulted to be over the minimal threshold of 10(-6) with 20-80% confidence.

Progression of squamous carcinoma cells to spindle carcinomas of mouse skin is associated with an imbalance of H-ras alleles on chromosome 7.

Analysis of benign and malignant mouse skin tumors had previously shown that amplification of a mutant H-ras allele or loss of the normal allele was generally seen only in high grade or spindle cell tumors. The normal:mutant ras gene dosage has been studied directly by polymerase chain reaction amplification of DNA derived from paraffin sections of carcinomas of defined histological types. Some tumors had virtually no signal corresponding to the normal allele and these were invariably spindle cell carcinomas. In four cases where both squamous and spindle cell components could be identified within the same tumor the spindle cell component had a higher mutant:normal gene ratio. Additional experiments on cell lines derived from squamous or spindle cell tumors have demonstrated a good correlation between the ratio of normal:mutant ras and the degree of invasiveness of the cells in in vitro assays.

Caloric restriction and 7,12-dimethylbenz(a)anthracene-induced mammary tumor growth in rats: alterations in circulating insulin, insulin-like growth factors I and II, and epidermal growth factor.

Caloric restriction (CR) inhibits many neoplastic diseases in rodents, yet the biochemical mechanism(s) for these effects are poorly understood. We have examined the effects of ad libitum (AL) feeding with 25 or 40% CR on the promotion of 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis in virgin female Sprague-Dawley rats. Further, we have also studied the influence of chronic CR on temporal alterations in circulating insulin, insulin-like growth factor I/somatomedin C, insulin-like growth factor II/multiplication-stimulating activity, and epidermal growth factor levels at 0, 1, 3, 5, 11, and 20 weeks in carcinogen- and vehicle-treated animals. Tumor incidence and multiplicity were markedly inhibited (P less than 0.05) with increasing CR. Fasting serum insulin-like growth factor I/somatomedin C levels exhibited a significant acute decline with CR at 1 and 3 weeks, but were comparable to AL-fed controls throughout the remainder of the 5-month study, despite continued differences in weight gain between AL and CR rats. Levels of insulin-like growth factor II/multiplication-stimulating activity exhibited no discernible pattern in relation to CR. Serum insulin levels showed age-dependent increases, but were affected by increasing CR at all time points. Insulin levels were significantly (P less than 0.05) reduced in 40% CR rats from 3 weeks onward compared to controls, while 25% CR resulted in nonsignificant (P less than 0.07) reductions throughout the study. No significant differences in growth factor levels were observed between 7,12-dimethylbenz(a)anthracene- and vehicle-treated rats. Circulating epidermal growth factor was not detectable in any treatment group regardless of the nature or duration of the dietary regimen, time of blood collection, or subsequent tumor-bearing status. These data suggest that decreased serum insulin-like growth factor I/somatomedin C and insulin levels with CR and their complex interactions in vivo may play a role in the inhibition of mammary tumor promotion by CR.

Growth factor binding to 7,12-dimethylbenz(a)anthracene-induced mammary tumors from rats subject to chronic caloric restriction.

Caloric restriction (CR) inhibits tumorigenesis in rodents. To understand the basis for this effect the binding of insulin, insulin-like growth factor I/somatomedin C (IGF-I/Sm-C), insulin-like growth factor II/multiplication stimulating activity (IGF-II/MSA), and epidermal growth factor were examined to membrane preparations of 7,12-dimethylbenz(a)anthracene-induced mammary adenocarcinomas and several normal tissues from female Sprague-Dawley rats. Animals were fed ad libitum (AL) or 25% and 40% calorically restricted diets. Large, palpable (LP) and small, less than or equal to 100 mg, nonpalpable (SNP) tumors were evaluated. Growth factor binding to tumors was differentially affected by CR. IGF-I/Sm-C binding was comparable for AL-LP, AL-SNP, and 25% CR-LP tumors, but elevated in 25% CR-SNP tumors. Scatchard analysis revealed high and low affinity IGF-I/Sm-C binding sites, with AL-SNP and 25% CR-SNP tumors exhibiting similar levels of high affinity sites and at a greater concentration than AL-LP and 25% CR-LP tumors. Insulin binding to mammary tumors was low, i.e., 8- to 13-fold lower than IGF-I/Sm-C binding. The 25% CR-LP and SNP tumors bound 2- to 5-fold more insulin than corresponding AL-LP and SNP tumors. Binding of IGF-II/MSA to these tumor preparations was high, approximately 11- to 25-fold greater than insulin binding, and was unaffected by CR or tumor size. The binding of epidermal growth factor was not detected in any tumor preparations. Receptor binding studies were confirmed with covalent cross-linking and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses. Normal tissues exhibited tissue- and growth factor-specific alterations in binding with host CR. Thus, alterations in growth factor binding were not tumor specific, but were less pronounced than in mammary tumors. These findings suggest alterations in IGF-I/Sm-C and insulin binding properties to tumors in relation to CR and tumor size may contribute, in part, to the inhibitory effects of CR on tumorigenesis.

Deletion and mutation analyses of the P16/MTS-1 tumor suppressor gene in human ductal pancreatic cancer reveals a higher frequency of abnormalities in tumor-derived cell lines than in primary ductal adenocarcinomas.

The putative tumor suppressor gene p16/CDKN2 encodes a specific inhibitor of cyclin D-cyclin-dependent kinase 4 complexes important in cell-cycle regulation and has been found to be deleted or mutated in a variety of human cancers. Thirty microdissected primary human ductal pancreatic carcinomas from patients not subject to radiotherapy or chemotherapy prior to surgical resection of their carcinomas and 18 human pancreatic carcinoma cell lines were analyzed by single-strand conformation polymorphism (SSCP) and DNA sequence analyses and PCR-based deletion analyses for mutations and homozygous deletions of the p16/CDKN2 gene, respectively. Homozygous deletions of the gene were found in five cell lines, and nonpolymorphic SSCP and DNA sequence alterations were found within exon 1 in four cell lines and exon 2 in three lines, for an overall frequency of deletions and mutations of 66%. In contrast, homozygous deletions of p16/CDKN2 were observed in three primary pancreatic carcinomas, and five primary tumors revealed SSCP and/or sequence abnormalities in exon 1 (one case) and exon 2 (four cases), a mutation and deletion frequency of 27%. Immunoblotting analyses confirmed the absence of p16/MTS-1 expression in actively proliferating cell lines with a homozygous deletion of the gene and low-to-moderate levels of p16/MTS-1 expression in cell lines possessing a normal RB-1 gene or protein. These findings suggest that, although p16/CDKN2 may play a role in the pathobiology of pancreatic cancer, inactivation of this putative tumor suppressor gene occurs more frequently in cell lines than in primary ductal pancreatic carcinomas.

Alterations of the p53 tumor suppressor gene during mouse skin tumor progression.

The two-stage murine skin tumorigenesis model is widely used to study the development of squamous cell neoplasias. We have investigated expression of the p53 and retinoblastoma tumor suppressor genes in eight murine skin tumor cell lines of varied histopathology and malignant potential, in seven in vivo-derived clones from these cell lines, and in 39 primary short-term cultures of similarly induced skin tumors at various stages of tumor progression. One squamous cell carcinoma cell line and three more malignant clones derived from it revealed mutations of the p53 protein by immunoprecipitation analyses despite normal-sized p53 transcripts. Sequence analysis identified the nature of the point mutations in these lines, a G----C transversion in codon 132. Mouse retinoblastoma transcripts and protein were unaltered in all the cell lines examined. Among short-term cultures of skin tumors, the p53 gene appeared normal in all papillomas and early well-differentiated carcinomas by Southern and immunoprecipitation analyses. In contrast, four of eight tumors from later stages of promotion (50-60 weeks) possessed alterations in p53, including loss of the p53 product, and loss of immunoreactivity with a murine-specific antibody recognizing only wild-type p53 protein. Loss of heterozygosity at the p53 locus was similarly observed in several more malignant tumors from later stages of promotion. In contrast retinoblastoma expression was normal regardless of the stage of promotion or histological grade of the tumor. Direct sequence analyses of exons 5 through 8 of the p53 gene in eight advanced murine skin tumors revealed a 25% incidence of p53 mutations. These point mutations were located in codons 245 and 263. Collectively, these data indicate that alterations in the p53 gene occur in 25 to 50% of murine skin tumors induced by the two-stage tumorigenesis protocol and are later events in murine skin tumor progression. Moreover, these alterations are associated with tumors possessing a more malignant and/or poorly differentiated phenotype.

Long term testing of Microbial Fuel Cells: Comparison of different anode materials.

This paper focuses on the long term operation and testing of three Microbial Fuel Cells (MFC) having three different anode materials: commercial carbon felt (C-FELT), polyaniline-deposited carbon felt (C-PANI) and carbon-coated Berl saddles (C-SADDLES). A mixed consortium from seawater was used as inoculum and acetate was used as substrate. Tests were conducted for four months under 1000Ω external load. The maximum power generation was obtained by C-SADDLES (102mWm(-2)) followed by C-FELT and C-PANI, respectively. A similar trend was obtained with the evaluation of electrical energy produced: C-SADDLES (2222J), C-PANI (2183J) and C-FELT (2114J). However, the performance of C-PANI decreased over time, most evidently due to degradation or deactivation of deposited polyaniline by the microorganisms' activity. These results provide evidence that the three-dimensional structure, C-SADDLES, offers excellent biocompatibility, high specific surface area, high conductivity and most importantly these properties are maintained for a long period of time.

Stable reintroduction of wild-type P53 (MTmp53ts) causes the induction of apoptosis and neuroendocrine-like differentiation in human ductal pancreatic carcinoma cells.

Pancreatic ductal adenocarcinoma is one of the major causes of cancer mortality in the industrialized world, having among the poorest prognosis of any malignancy. Mutations or alterations in the p53 tumor suppressor gene/protein are observed in 50-70% of these cancers, yet little information is available regarding the phenotypic effects of restoration of wild-type (wt) p53 function in pancreatic ductal carcinoma cells. The consequences of stable reintroduction of wt p53 on apoptosis and differentiation was examined in a poorly differentiated pancreatic carcinoma cell line (Panc-1), possessing only mutant (mt) p53 (codon 273 mutation). Cells were transfected with a temperature-sensitive mouse p53val135 (tsp53) vector under additional control of a genetically-modified metallothionein promoter. This tsp53 has a 'mt' phenotype at 37.5 degrees C, and a 'wt' phenotype at 32.5 degrees C and the presence of 100 microM ZnCl2. Stable expression of wt p53 caused upregulation of the p21/WAF1 gene, and G1 growth arrest as shown by flow cytometry and BrdU labeling. Additionally, apoptosis was induced 8-12 post-induction in the majority of the cells (60-70%), as demonstrated by morphological changes, in situ TdT labeling and internucleosomal laddering. However, a subpopulation (30%) of the transfectants survived this apoptotic fate. Unlike the epithelial parental Panc-1 cells, these cells exhibited the appearance of a neuroendocrine-like phenotype with extensive branch-like processes, and marked cytoplasmic and cytoskeletal immunostaining for tau-2, synaptophysin, and chromogranin A. These studies suggest that stable and regulated expression of wt p53 can have multiple phenotypic consequences (apoptosis and altered differentiation to a neuroendocrine-like phenotype) in poorly-differentiated pancreatic carcinoma cells.

Human pancreatic carcinomas and cell lines reveal frequent and multiple alterations in the p53 and Rb-1 tumor-suppressor genes.

The molecular pathology of human pancreatic cancer is poorly understood, particularly with regard to the role of known tumor-suppressor genes. We have examined the expression of the p53 and Rb-1 tumor-suppressor genes in seven human pancreatic carcinoma cell lines and 10 primary pancreatic carcinomas. Examination of the Rb-1 gene by Northern hybridization and immunoprecipitation analyses revealed the absence of Rb-1 protein expression in two cell lines. Moreover, regions of absent nuclear staining in two primary pancreatic carcinomas were detected by immunohistochemical analysis. Investigation of p53 by Southern, Northern, immunohistochemical and immunoprecipitation analyses revealed multiple abnormalities, including gross rearrangements in two cell lines, the absence of detectable p53 transcript in two cell lines and a truncated transcript in one line. Six cell lines overexpressed p53 protein, while one line revealed the absence of p53 product by immunohistochemical and immunoprecipitation analyses. Sequence analysis of exons 5-8 of the p53 gene confirmed these analyses, revealing missense mutations in all seven cell lines in codons 181, 220, 248, 249, 265, 272 and 273. Of 10 mutations identified, nine were transitions and 50% were in codon 273. Immunohistochemical analyses of frozen primary pancreatic carcinomas revealed positive nuclear staining for p53 in 40% of cases. Mutations were identified in codons 238 and 286 and in intron 9 in several representative specimens. Alterations in the p53 and Rb-1 genes may be important features in the development of human pancreatic cancer.

Biochemical alterations in 7,12-dimethylbenz[a]anthracene-induced mammary tumors from rats subjected to caloric restriction.

Caloric restriction reduces the incidence and progression of a broad spectrum of neoplastic diseases, yet little is known about the biochemical and molecular mechanisms involved. Profiles of enzyme activities of importance in cellular energy utilization were examined in 7,12-dimethylbenz[a]anthracene-induced (DMBA) mammary adenocarcinomas from rats fed ad libitum or calorically restricted diets. The diets provided equal nutrients except for fewer carbohydrate-derived calories; graded caloric restriction was 10, 20, 30 and 40%. The specific activities of hexokinase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase, malic enzyme and fructose-1,6-bisphosphatase were all elevated to varying degrees in both large palpable and small, non-palpable tumors from calorically restricted hosts compared to activities in tumors from ad libitum-fed rats. Phosphofructokinase activity was increased in palpable tumors from calorically restricted hosts but markedly reduced in non-palpable tumors. These results suggest adaptive or compensatory alterations in tumor enzyme profiles in response to the altered nutritional state of the host.

The Trk tyrosine kinase inhibitor CEP-701 (KT-5555) exhibits significant antitumor efficacy in preclinical xenograft models of human pancreatic ductal adenocarcinoma.

The aggressive behavior and poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is associated with an increased expression of many growth factors and their cognate receptors. We have previously demonstrated the aberrant expression of the Trk receptors (Trks A, B, and C), enhanced tumor stromal expression of neurotrophins in primary PDAC specimens and human PDAC-derived cell lines, and a dose-dependent biological response of PDAC cells (in vitro invasiveness) to selective neurotrophins (Miknyoczki, S. J., et al., Int. J. Cancer, 81: 417-427, 1999). On the basis of these data, we have evaluated the therapeutic potential of inhibiting neurotrophin-Trk interactions using a selective and potent Trk tyrosine kinase inhibitor (CEP-701) in several preclinical models of human PDAC. CEP-701 is currently approved for clinical trials within the United States We demonstrate that CEP-701 administration at 10 mg/kg s.c. b.i.d. 5 days a week for 21-28 days inhibited tumor growth in a statistically significant manner in Panc-1, AsPc-1, BxPc-3, Colo 357, and MiaPaCa2 s.c. xenografts in athymic nude mice compared with vehicle-treated controls. Reductions in tumor growth volume of 50-70% relative to vehicle-treated controls were observed in xenografts responsive to CEP-701 administration. Significant reductions of in vivo PDAC tumor invasiveness were likewise observed in four of six CEP-701-treated rat tracheal xenografts implanted s.c. in athymic nude mice. The antitumor efficacy of CEP-701 was observed in the absence of pronounced morbidity or toxicity in vivo. Taken together, these data suggest that CEP-701 may be effective as a potential therapeutic agent in the treatment or management of PDAC.