Rapamycin-mediated FOXO1 inactivation reduces the anticancer efficacy of rapamycin.

BACKGROUND: Mammalian target of rapamycin (mTOR) inhibitors such as rapamycin have shown modest effects in cancer therapy due in part to the removal of a negative feedback loop leading to the activation of the phosphatidylinositol 3-kinase/Akt (PI3K/Akt) signaling pathway. In this report, we have investigated the role of FOXO1, a downstream substrate of the PI3K/Akt pathway in the anticancer efficacy of rapamycin. MATERIALS AND METHODS: Colon cancer cells were treated with rapamycin and FOXO1 phosphorylation was determined by Western blot. Colon cancer cells transfected with a constitutively active mutant of FOXO1 or a control plasmid were treated with rapamycin and the antiproliferative efficacy of rapamycin was monitored. RESULTS: Rapamycin induced the phosphorylation of FOXO1 as well as its translocation from the nucleus to the cytoplasm, leading to FOXO1 inactivation. The expression of an active mutant of FOXO1 in colon cancer cells potentiated the antiproliferative efficacy of rapamycin in vitro and its antitumor efficacy in vivo. CONCLUSION: Taken together these results show that rapamycin-induced FOXO1 inactivation reduces the antitumor efficacy of rapamycin.

L'immunoscintigraphie par les anticorps monoclonaux radiomarqués. Evolution d'une méthode de diagnostic du cancer et espoir d'une nouvelle forme de thérapie [Immunoscintigraphy using radio-labeled monoclonal antibodies. Development of a method of cancer diagnosis and hopes for a new form of therapy].

Personal results are presented to illustrate the development of immunoscintigraphy for the detection of cancer over the last 12 years, from the early experimental results in nude mice grafted with human colon carcinoma to the most modern form of immunoscintigraphy applied to patients, using I123 labeled Fab fragments from monoclonal anti-CEA antibodies detected by single photon emission computerized tomography (SPECT). The first generation of immunoscintigraphy used I131 labeled, immunoadsorbent purified, polyclonal anti-CEA antibodies and planar scintigraphy, as the detection system. The second generation used I131 labeled monoclonal anti-CEA antibodies and SPECT, while the third generation employed I123 labeled fragments of monoclonal antibodies and SPECT. The improvement in the precision of tumor images with the most recent forms of immunoscintigraphy is obvious. However, we think the usefulness of immunoscintigraphy for routine cancer management has not yet been entirely demonstrated. Further prospective trials are still necessary to determine the precise clinical role of immunoscintigraphy. A case report is presented on a patient with two liver metastases from a sigmoid carcinoma, who received through the hepatic artery a therapeutic dose (100 mCi) of I131 coupled to 40 mg of a mixture of two high affinity anti-CEA monoclonal antibodies. Excellent localisation in the metastases of the I131 labeled antibodies was demonstrated by SPECT and the treatment was well tolerated. The irradiation dose to the tumor, however, was too low at 4300 rads (with 1075 rads to the normal liver and 88 rads to the bone marrow), and no evidence of tumor regression was obtained. Different approaches for increasing the irradiation dose delivered to the tumor by the antibodies are considered.

Rétablissement postopératoire optimisé, applique aux patients après cystectomie [Enhanced recovery after surgery applied to cystectomy patients].

Enhanced Recovery After Surgery (ERAS) is a multimodal concept combining pre, intra and postoperative evidence-based care elements to reduce surgical stress. ERAS pathways have been shown to significantly reduce morbidity, length of hospital stay and total costs when applied to colorectal surgery. It is therefore considered standard of care in this specialty. There can be no doubt that ERAS principles can be applied also in other major surgeries. However, uncritical application of the guidelines issued from colonic procedures seems inappropriate as the surgical procedures in pelvic cancer surgery differ considerably. This article reports on the first steps of an ERAS project and his introduction in urology.

Sagittal abdominal diameter is a better predictor than body mass index for duration of laparoscopic left colectomy.

BACKGROUND: Visceral obesity (VO) increases technical difficulty in laparoscopic surgery. The body mass index (BMI) does not always correlate to intra-abdominal fat distribution. Our hypothesis was that simple anthropometric measures that reflect VO, could predict technical difficulty in laparoscopic colorectal surgery, as reflected by the operative time, more accurately than the BMI. METHODS: Charts of all consecutive patients who underwent laparoscopic left colon resection in our institution between 2007 and 2010 were reviewed retrospectively. On a preoperative CT scan, anthropometric measures were taken on an axial plane at the L4-L5 level. Demographic, operative and anthropometric CT measures were correlated with the operative time. Logistic regression analysis was performed to assess the value of anthropometric CT measures or BMI to predict the duration of the colectomy. RESULTS: 121 patients with elective left colon resection for benign (56%) or malignant disease (44%) were included. There were 74 sigmoid resections (61%), 21 left hemicolectomies (17%) and 26 low anterior resections (22%). A longer sagittal abdominal diameter (≥24.8 cm) was significantly associated with longer corrected operative time (248 vs. 228 min, p = 0.043). In multivariate analysis, greater sagittal abdominal diameter, sagittal internal diameter and abdominal perimeter were significantly associated with longer operative time. No significant association was found for the BMI neither in univariate nor in multivariate analysis. CONCLUSIONS: This study suggests that simple linear measures taken on a CT scan, such as sagittal abdominal diameter, sagittal internal diameter and abdominal perimeter, may predict longer operative time in laparoscopic left colonic resections more accurately than BMI.

In this issue.

A new issue, once again a bouquet of attractive papers. First of all the paper by Droit-Dupré et al. (10.1007/s00428-015-1724-9). The group studied colonic adenocarcinomas, not otherwise specified, by immunohistochemistry for the expression of markers of intestinal epithelial cell differentiation. Hierarchical clustering analysis identified a major cluster of two thirds of the case series, expressing cytokeratin 20, CDX2 and MUC2 and invariably mismatch repair competent, which they called crypt-like. In stage III colon cancer, the crypt-like cluster had a better prognosis. The paper is a relatively simple example of what is happening in cancer classification beyond morphology: multiparameter differentiation and (epi)genomic markers defining new subtypes of cancer with potential clinical significance in clinical decision making.

Factors associated with durable response to infliximab in Crohn's disease 5 years and beyond : a multicenter international cohort

BACKGROUND: Infliximab (IFX) has been used for over a decade worldwide. Less is known about the natural history of IFX use beyond a few years and which patients are more likely to sustain benefits. METHODS: Patients with Crohn's disease (CD) exposed to IFX from Massachusetts General Hospital, Boston, Saint-Antoine Hospital, Paris, and the Swiss IBD Cohort Study were identified through retrospective and prospective data collection, complemented by chart abstraction of electronic medical records. We compared long-term users of IFX (>5 yr of treatment, long-term users of infliximab [LTUI]), with non-LTUI patients to identify prognostic factors. RESULTS: We pooled data on 1014 patients with CD from 3 different databases, of whom 250 were defined as LTUI. The comparison group comprised 290 patients with CD who discontinued IFX: 48 primary nonresponses, 95 loss of responses, and 147 adverse events. Factors associated with LTUI were colonic involvements and an earlier age at the start of IFX. The prevalence of active smokers and obese patients differed markedly, but inversely, between American and European centers but did not impact outcome. The discontinuation rate was stable around 3% to 6%, each year from years 3 to 10. CONCLUSIONS: Young age at start of IFX and colonic CD are factors associated with a beneficial long-term use of IFX. After 5 years of IFX, there is still a 3% to 5% discontinuation rate annually. Several factors associated with a good initial response such as nonsmoker and shorter disease duration at IFX initiation do not seem associated with a longer term response.

Systematic evaluation of clinical predictors of aggressive ulcerative colitis

Background: Studies evaluating risk factors associated with an "aggressive" disease course in ulcerative colitis (UC) are scarce. A recent definition of "aggressive" UC incorporated the following characteristics: 1) high relapse rate, 2) need for surgery, 3) development of colorectal cancer, and 4) presence of extraintestinal manifestations (EIM). The following factors for an aggressive / disabling disease course in UC have been identified so far: age < 40 years at S140 Poster presentations UC diagnosis, pancolitis, concomitant primary sclerosing cholangitis, and deep ulcerations of the colonic mucosa. We aimed to evaluate risk factors for an "aggressive" disease course in UC patients. Methods: Data from the Swiss IBD cohort study were analyzed. Patients were recruited from university centers (80%), regional hospitals (19%), and private practices (1%). We applied the following definition for "aggressive" UC: 1) patients ever treated with TNFantagonists or calcineurin inhibitors (tacrolimus / cyclosporine), and 2) need for (procto)-colectomy. Non-normal data are presented as median and interquartile range [IQR].

Incidence des cancers et polypes colorectaux dans le canton de Vaud, 1983-2007: tendances et déterminants

Le cancer colorectal atteint, chaque année, plus d'un million de personnes dans le monde et plus de 500'000 en meurent [1]. Il affecte de manière très inégalitaire les différentes parties du monde. En effet, s'il constitue un problème de santé publique majeur dans des régions telles que l'Amérique du Nord, l'Europe ou l'Océanie (incidence supérieure à 50 pour 100'000), il est nettement plus rare dans certains pays d'Asie, d'Afrique ou d'Amérique du Sud (incidence inférieure à 10 pour 100'000) [2]. Aux Etats-Unis, on estime que 5 à 6% de la population générale présentera un cancer colorectal au cours de sa vie [3]. En Suisse, le cancer colorectal est le deuxième cancer le plus mortel, avec quelque 1'600 décès par an, après le cancer du poumon [4]. Avec 4'000 nouveaux cas annuels, il représente 11% de tous les cancers chez l'homme et chez la femme [5]. Le cancer colorectal est le troisième cancer le plus fréquent après celui du poumon et de la prostate chez l'homme, alors qu'il n'est précédé chez la femme que par le cancer du sein. Pour la période 2003-07, l'incidence en Suisse est estimée à 50 cas/100'000 hommes et 32 cas/100'000 femmes (taux standardisés selon la population européenne) [5] et son taux de survie relative à 5 ans est de 60%, ce qui en fait le taux le plus élevé d'Europe [6]. Le fait que l'incidence chez les migrants ait tendance à rattraper celle des indigènes en moins d'une génération suggère que les facteurs environnementaux jouent un rôle prédominant dans la carcinogénèse des tumeurs colorectales [7]. Cependant, d'autres facteurs, notamment génétiques, interviennent dans la survenue des cancers colorectaux. En effet, dans des conditions de vie similaires, on observe une incidence de cancers colorectaux différente entre différentes ethnies. Des études américaines ont par exemple montré une incidence plus élevée chez les noirs (48 pour 100'000) que chez les blancs (40/100'000) ou les hispaniques (26/100'000) [8]. Les hommes sont plus fréquemment touchés par le cancer colorectal que les femmes, avec un sexe ratio de 1,5 [9]. Les premiers cas de cancers colorectaux apparaissent à partir de 25 ans et l'incidence augmente de manière quasi exponentielle jusqu'à un âge de 75-80 ans, puis se stabilise [10]. L'âge moyen au diagnostic se situe entre 65 et 70 ans. Environ 66% des cancers colorectaux sont localisés dans le côlon (dans l'ordre décroissant: au niveau du sigmoïde, du côlon ascendant, descendant et transverse), 27% dans le rectum, 4% dans l'anus tandis qu'environ 4% restent multiples et indéfinis [10]. Notons encore, qu'à des fins de comparaisons épidémiologiques, les cancers du côlon, du rectum et de l'anus sont souvent regroupés dans l'unique groupe des tumeurs colorectales.

Characteristics of non-responders to self-reported questionnaires in a large inflammatory bowel disease cohort study.

BACKGROUND: A major threat to the validity of longitudinal cohort studies is non-response to follow-up, which can lead to erroneous conclusions. The objective of this study was to evaluate the profile of non-responders to self-reported questionnaires in the Swiss inflammatory bowel disease (IBD) Cohort. METHODS: We used data from adult patients enrolled between November 2006 and June 2011. Responders versus non-responders were compared according to socio-demographic, clinical and psychosocial characteristics. Odds ratio for non-response to initial patient questionnaire (IPQ) compared to 1-year follow-up questionnaire (FPQ) were calculated. RESULTS: A total of 1943 patients received IPQ, in which 331 (17%) did not respond. Factors inversely associated with non-response to IPQ were age >50 and female gender (OR = 0.37; p < 0.001 respectively OR = 0.63; p = 0.003) among Crohn's disease (CD) patients, and disease duration >16 years (OR = 0.48; p = 0.025) among patients with ulcerative colitis (UC). FPQ was sent to 1586 patients who had completed the IPQ; 263 (17%) did not respond. Risk factors of non-response to FPQ were mild depression (OR = 2.17; p = 0.003) for CD, and mild anxiety (OR = 1.83; p = 0.024) for UC. Factors inversely associated with non-response to FPQ were: age >30 years, colonic only disease location, higher education and higher IBD-related quality of life for CD, and age >50 years or having a positive social support for UC. CONCLUSIONS: Characteristics of non-responders differed between UC and CD. The risk of non-response to repetitive solicitations (longitudinal versus transversal study) seemed to decrease with age. Assessing non-respondents' characteristics is important to document potential bias in longitudinal studies.

Rectal enema is an alternative to full mechanical bowel preparation for primary rectal cancer surgery.

AIM: According to the French GRECCAR III randomized trial, full mechanical bowel preparation (MBP) for rectal surgery decreases the rate of postoperative morbidity, in particular postoperative infectious complications, but MBP is not well tolerated by the patient. The aim of the present study was to determine whether a preoperative rectal enema (RE) might be an alternative to MBP. METHODS: An analysis was performed of 96 matched cohort patients undergoing rectal resection with primary anastomosis and protective ileostomy at two different university teaching hospitals, whose rectal cancer management was comparable except for the choice of preoperative bowel preparation (MBP or RE). Prospective databases were retrospectively analysed. RESULTS: Patients were well matched for age, gender, body mass index and Charlson index. The surgical approach and cancer characteristics (level above anal verge, stage and use of neoadjuvant therapy) were comparable between the two groups. Anastomotic leakage occurred in 10% of patients having MBP and in 8% having RE (P = 1.00). Pelvic abscess formation (6% vs 2%, P = 0.63) and wound infection (8% vs 15%, P = 0.55) were also comparable. Extra-abdominal infection (13% vs 13%, P = 1.00) and non-infectious abdominal complications such as ileus and bleeding (27% and 31%, P = 0.83) were not significantly different. Overall morbidity was comparable in the two groups (50% vs 54%, P = 0.83). CONCLUSION: A simple RE before rectal surgery seems not to be associated with more postoperative infectious complications nor a higher overall morbidity than MBP.

Caveolin-1 down-regulates inducible nitric oxide synthase via the proteasome pathway in human colon carcinoma cells.

To investigate whether caveolin-1 (cav-1) may modulate inducible nitric oxide synthase (iNOS) function in intact cells, the human intestinal carcinoma cell lines HT29 and DLD1 that have low endogenous cav-1 levels were transfected with cav-1 cDNA. In nontransfected cells, iNOS mRNA and protein levels were increased by the addition of a mix of cytokines. Ectopic expression of cav-1 in both cell lines correlated with significantly decreased iNOS activity and protein levels. This effect was linked to a posttranscriptional mechanism involving enhanced iNOS protein degradation by the proteasome pathway, because (i) induction of iNOS mRNA by cytokines was not affected and (ii) iNOS protein levels increased in the presence of the proteasome inhibitors N-acetyl-Leu-Leu-Norleucinal and lactacystin. In addition, a small amount of iNOS was found to cofractionate with cav-1 in Triton X-100-insoluble membrane fractions where also iNOS degradation was apparent. As has been described for endothelial and neuronal NOS isoenzymes, direct binding between cav-1 and human iNOS was detected in vitro. Taken together, these results suggest that cav-1 promotes iNOS presence in detergent-insoluble membrane fractions and degradation there via the proteasome pathway.

Caveolin-1-mediated post-transcriptional regulation of inducible nitric oxide synthase in human colon carcinoma cells.

Reactive oxygen species are now widely recognized as important players contributing both to cell homeostasis and the development of disease. In this respect nitric oxide (NO) is no exception. The discussion here will center on regulation of the inducible form of nitric oxide synthase (iNOS) for two reasons. First, only iNOS produces micromolar NO concentrations, amounts that are high by comparison with the picomolar to nanomolar concentrations resulting from Ca2(+)-controlled NO production by endothelial eNOS or neuronal nNOS. Second, iNOS is not constitutively expressed in cells and regulation of this isoenzyme, in contrast to endothelial eNOS or neuronal nNOS, is widely considered to occur at the transcriptional level only. In particular, we were interested in the possibility that caveolin-1, a protein that functions as a tumor suppressor in colon carcinoma cells (Bender et al., 2002; this issue), might regulate iNOS activity. Our results provide evidence for the existence of a post-transcriptional mechanism controlling iNOS protein levels that involves caveolin-1-dependent sequestration of iNOS within a detergent-insoluble compartment. Interestingly, despite the high degree of conservation of the caveolin-1 scaffolding domain binding motif within all NOS enzymes, the interaction detected between caveolin-1 and iNOS in vitro is crucially dependent on presence of a caveolin-1 sequence element immediately adjacent to the scaffolding domain. A model is presented summarizing the salient aspects of these results. These observations are important in the context of tumor biology, since down-regulation of caveolin-1 is predicted to promote uncontrolled iNOS activity, genotoxic damage and thereby facilitate tumor development in humans.

Frequent nitric oxide synthase-2 expression in human colon adenomas: implication for tumor angiogenesis and colon cancer progression.

An increased expression of nitric oxide synthase (NOS) has been observed in human colon carcinoma cell lines as well as in human gynecological, breast, and central nervous system tumors. This observation suggests a pathobiological role of tumor-associated NO production. Hence, we investigated NOS expression in human colon cancer in respect to tumor staging, NOS-expressing cell type(s), nitrotyrosine formation, inflammation, and vascular endothelial growth factor expression. Ca2+-dependent NOS activity was found in normal colon and in tumors but was significantly decreased in adenomas (P < 0.001) and carcinomas (Dukes' stages A-D: P < 0.002). Ca2+-independent NOS activity, indicating inducible NOS (NOS2), is markedly expressed in approximately 60% of human colon adenomas (P < 0.001 versus normal tissues) and in 20-25% of colon carcinomas (P < 0.01 versus normal tissues). Only low levels were found in the surrounding normal tissue. NOS2 activity decreased with increasing tumor stage (Dukes' A-D) and was lowest in colon metastases to liver and lung. NOS2 was detected in tissue mononuclear cells (TMCs), endothelium, and tumor epithelium. There was a statistically significant correlation between NOS2 enzymatic activity and the level of NOS2 protein detected by immunohistochemistry (P < 0.01). Western blot analysis of tumor extracts with Ca2+-independent NOS activity showed up to three distinct NOS2 protein bands at Mr 125,000-Mr 138,000. The same protein bands were heavily tyrosine-phosphorylated in some tumor tissues. TMCs, but not the tumor epithelium, were immunopositive using a polyclonal anti-nitrotyrosine antibody. However, only a subset of the NOS2-expressing TMCs stained positively for 3-nitrotyrosine, which is a marker for peroxynitrite formation. Furthermore, vascular endothelial growth factor expression was detected in adenomas expressing NOS2. These data are consistent with the hypothesis that excessive NO production by NOS2 may contribute to the pathogenesis of colon cancer progression at the transition of colon adenoma to carcinoma in situ.