GILP family: a stress-responsive group of plant proteins containing a LITAF motif.

Lipopolysaccharide-induced tumor necrosis factor-α (LITAF) is a membrane protein that is highly dependent on correct location to exert transcription factor activity and protein quality control. In humans, LITAF, PIG7 (p53-inducible gene 7), and SIMPLE (small integral membrane protein of the lysosome/late endosome) refer to the same gene, which acts as a tumor suppressor. Several studies have shown that the transcription factor activity and nuclear translocation of LITAF protein are critical for the induction of several immune cells via classical pathways. In plants, LITAF protein corresponds to the plasma membrane protein AtGILP (Arabidopsis thaliana GSH-induced LITAF domain protein). The conservation of LITAF proteins across species and their putative role is still unclear. In this study, we investigate the LITAF-containing proteins, which we call GILP proteins, in Viridiplantae. We identified a total of 59 genes in 46 species, whose gene copies range from one to three. Phylogenetic analysis showed that multiple copies were originated via block duplication posteriorly to monocot and eudicot separation. Analysis of the LITAF domain of GILP proteins allowed the identification of a putative domain signature in Viridiplantae, containing a CXXCX41HXCPXC motif. The subcellular location for the majority of GILP proteins was predicted to be in the plasma membrane, based on a transmembrane domain positioned within the LITAF domain. In silico analysis showed that the GILP genes are neither tissue-specific nor ubiquitously expressed, being responsive to stress conditions. Finally, investigation of the GILP protein network resulted in the identification of genes whose families are known to be involved with biotic and/or abiotic stress responses. Together, the expression modulation of GILP genes associated with their plasma membrane location suggests that they could act in the signaling of biotic/abiotic stress response in plants.

Kinetic and mechanistic study of the reaction of OH radicals with methylated benzenes: 1,4-dimethyl-, 1,3,5-trimethyl-, 1,2,4,5-, 1,2,3,5- and 1,2,3,4-tetramethyl-, pentamethyl-, and hexamethylbenzene.

The reaction of OH radicals with a series of methylated benzenes was studied in a temperature range 300-350 K using a flash-photolysis resonance fluorescence technique. Reversible OH additions led to complex OH decays dependent on the number of distinguishable adducts. Except for hexamethylbenzene, triexponential OH decay curves were obtained, consistent with formation of at least two adduct species. For three compounds that can strictly form two adduct isomers for symmetry reasons (1,4-dimethyl-, 1,3,5-trimethyl-, and 1,2,4,5-tetramethylbenzene) with OH bound ortho or ipso with respect to the methyl groups, OH decay curves were analysed in terms of a reaction mechanism in which the two adducts can be formed directly by OH addition or indirectly by isomerization. In all cases one adduct (add1) is dominating the decomposition back to OH. The other (add2) is more elusive and only detectable at elevated temperatures, similar to the single OH adduct of hexamethylbenzene. Two limiting cases of the general reaction mechanism could be examined quantitatively: reversible formation of add2 exclusively in the OH reaction or by isomerization of add1. Total OH rate constants, adduct loss rate constants and products of forward and reverse rate constants of reversible reactions were determined. From these quantities, adduct yields, equilibrium constants, as well as reaction enthalpies and entropies were derived for the three aromatics. Adduct yields strongly depend on the selected reaction model but generally formation of add1 predominates. For both models equilibrium constants of OH reactions lie between those of OH + benzene from the literature and those obtained for OH + hexamethylbenzene. The corresponding reaction enthalpies of add1 and add2 formations are in a range -87 ± 20 kJ mol(-1), less exothermic than for hexamethylbenzene (-101 kJ mol(-1)). Reaction enthalpies of possible add1 → add2 isomerizations are comparatively small. Because results for 1,3,5-trimethylbenzene are partly inconsistent with a direct formation of add2, we promote the existence of isomerization reactions. Moreover, based on available theoretical work in the literature, add1 and add2 are tentatively identified as ortho and ipso adducts, respectively. Total OH rate constants were obtained for all title compounds. They can be described by Arrhenius equations: kOH = A × exp(-B/T). The parameters ln(A/(cm(3) s(-1))) = -25.6 ± 0.3, -25.3 ± 0.6, -27.3 ± 0.3, -24.6 ± 0.3, -26.2 ± 0.4, -26.2 ± 0.4 and -24.5 ± 0.2, and B/K = -160 ± 90, -550 ± 180, -1120 ± 90, -330 ± 100, -820 ± 100, -980 ± 130, and -570 ± 40 were determined for 1,4-dimethyl-, 1,3,5-trimethyl-, 1,2,4,5-, 1,2,3,5- and 1,2,3,4-tetramethyl-, pentamethyl-, and hexamethylbenzene.

VEGFR-2, CXCR-2 and PAR-1 germline polymorphisms as predictors of survival in pancreatic carcinoma.

BACKGROUND: Hypoxic environment of pancreatic cancer (PC) implicates high vascular in-growth, which may be influenced by angiogenesis-related germline polymorphisms. Our purpose was to evaluate polymorphisms of vascular endothelial growth factor receptor 2 (VEGFR-2), CXC chemokine receptor 2 (CXCR-2), proteinase-activated receptor 1 (PAR-1) and endostatin (ES) as prognostic markers for disease-free (DFS) and overall survival (OS) in PC. PATIENTS AND METHODS: Genotyping of 173 patients, surgically treated for PC between 2004 and 2011, was carried out by TaqMan(®) genotyping assays or polymerase chain reaction. Chi-square test, Kaplan-Meier estimator and Cox regression hazard model were used to assess the prognostic value of selected polymorphisms. RESULTS: VEGFR-2 -906 T/T and PAR-1 -506 Del/Del genotypes predicted longer DFS (P = 0.003, P = 0.014) and OS (VEGFR-2 -906, P = 0.011). CXCR-2 +1208 T/T genotype was a negative predictor for DFS (P < 0.0001). Combined analysis for DFS and OS indicated that patients with the fewest number of favorable genotypes simultaneously present (VEGFR-2 -906 T/T, CXCR-2 +1208 C/T or C/C and PAR-1 -506 Del/Del) were at the highest risk for recurrence or death (P < 0.0001). CONCLUSION: VEGFR-2 -906 C>T, CXCR-2 +1208 C>T and PAR-1 -506 Ins/Del polymorphisms are potential predictors for survival in PC.

Regional Disparities in Diabetes Care for Pediatric Patients with Type 1 Diabetes. A Cross-sectional DPV Multicenter Analysis of 24,928 German Children and Adolescents.

BACKGROUND: Data on regional differences in the quality of medical care in Germany are scarce. This study aimed to compare outcome quality and medical treatment of pediatric patients with type 1 diabetes between the federal states of Germany. METHODS: 24,928 patients (< 18 years of age) with type 1 diabetes and German residence were selected from the Diabetes-Patienten-Verlaufsdokumentation database. Indicators of outcome quality were HbA1C, overweight prevalence, and rate of severe hypoglycemia. To reflect medical treatment, use of insulin pumps and use of rapid-acting or long-acting insulin analogues were analyzed. Logistic regression models were created for binary variables with federal state as independent predictor. Linear regression was applied for HbA1C and Poisson regression for rate of severe hypoglycemia. Confounders: Sex, age, diabetes duration, migratory background. RESULTS: Disparity was observed for indicators of outcome quality between the 16 federal states of Germany (all p<0.05). After adjustment, HbA1C varied between 55.8 mmol/mol and 67.3 mmol/mol, overweight prevalence between 10.0 and 15.3%, severe hypoglycemia ranged from 0.06 events/PY to 0.21 events/PY. Overall, the best outcome quality appeared to be present in Saxony. Medical treatment also differed. The percentage of pediatrics on insulin pumps varied between 26.3 and 51.8%. The use of rapid-acting analogues ranged from 56.6 to 96.2% and the use of long-acting analogues varied between 41.9 and 96.9% (all p<0.0001). CONCLUSIONS: Medical treatment and outcome quality in pediatrics with type 1 diabetes differed within Germany. Disparities in individual socioeconomic status, regional deprivation, or differences in medical reimbursement decisions might have contributed to the patterns observed.

The involvement of tertiary conformational changes and the role of the alpha-chain-binding sites on oxygen-linked chloride release from human hemoglobin.

Chloride anions, when bound to human hemoglobin, lower the affinity for oxygen and increase the alkaline Bohr effect. These oxygen-linked characteristics are attributed to the preferential binding of Cl- to both alpha- and beta-chains in their deoxy configuration. It is demonstrated that the release of Cl- upon oxygenation is mainly due to tertiary changes, as shown by the effect of the anion on K1, the affinity constant of hemoglobin for oxygen at a very low saturation level (y less than or equal to 1.5%) where the cooperativity is unity. Investigation of the chloride effect on adult hemoglobin specifically carbamylated at the N-terminal valine of the alpha-chains, indicated a large inhibition of the effect of Cl-. The alpha-chain-binding sites appear to be the sites of the greatest affinity for the anion.

Temperature independence of the alkaline Bohr effect in pig red cells and pig haemoglobin solutions.

The influence of temperature on the oxygen affinity and the alkaline Bohr effect of pig red cells and pig hemoglobin solutions has been compared to that of human adult red cells and human adult hemoglobin. Pig red cells and pig Hb evidence a lower affinity for oxygen in various conditions of pH, temperature and salt concentration, in the presence as well as in the absence of organic phosphates. It has been observed that the alkaline Bohr effect of pig Hb was reduced by 20-25% compared to Hb A0 and independent of changes in temperature, contrary to human Hb A0. Titrations of pig Hb with C1- indicate a lower heterotropic effect of this anion at low concentration of the salt. It is concluded that this may be the origin of the temperature independence of the alkaline Bohr effect in pig Hb. Conversely, the temperature dependence of the alkaline Bohr effect of Hb A0 should be related to the oxygen-linked binding of C1- at the alpha 1-alpha 2 interface.

Hemoglobin Calais [beta 76 (E20) Ala----Pro]: a hemoglobin variant with decreased intrinsic oxygen affinity.

Hb Calais [beta 76 (E20) Ala----Pro] is a new human hemoglobin variant displaying a decreased oxygen affinity. The only electrophoretical difference with Hb A was a slightly more acidic isoelectric point. A 2-fold decrease in the oxygen affinity was found by equilibrium measurements performed in a suspension of intact red blood cells and in the lysate. It was confirmed by kinetic studies of the purified abnormal hemoglobin. The rate of methemoglobin formation at 37 degrees C of Hb Calais was also increased relative to Hb A. The mechanism by which the Pro for Ala substitution of an external residue in the beta-chains results in these profound functional abnormalities is unclear. Subtle changes at the heme pocket, at a distance from the mutation, may be a plausible explanation for the effects observed.

Structure and function of Hb Saint-Jacques (alpha 2 beta 2 140 (H18) Ala----Thr): a new high-oxygen-affinity variant with altered bisphosphoglycerate binding.

A low P50 value in a fresh red blood cell suspension was discovered in a polycythemic patient (Hb 19 g X dl-1). Routine acid and alkaline electrophoreses of the hemolysate were identical to normal hemolysate. Isoelectrofocusing (pH gradient 6-8) did not reveal any abnormal band whether performed with the fully liganded or deoxygenated samples. Precise analyses of the oxygen dissociation curves of the propositus' red cells demonstrated a biphasic Hill plot, a normal Bohr effect and low interaction with 2,3-bisphosphoglycerate (2,3-DPG). Studies on the unfractionated hemolysate confirmed these observations and the inhibition of the effect of organic phosphates. Structural studies were carried out on the mixture of beta A + beta X chains and revealed the presence of two beta Tp14 peptides. Sequencing the abnormal beta Tp14 peptide showed the substitution Ala----Thr of the beta 140 (H18) residue. This new variant was named Hb Saint-Jacques. Examination of the three dimensional model of HbAo indicates that the substitution beta 140 (H18) Ala----Thr induces van der Waals interactions with the nearby lysine-82 (EF6) and leucine-81 (EF5) and a displacement of the EF corner of the beta chains. This is likely to change the normal position of the lysine-82 (EF6), a major anionic binding site in the central cavity between the two beta chains. Functional studies confirm the interpretation of a steric hindrance inhibiting the binding of large organic phosphates to Hb Saint-Jacques.

Allosteric transition in triply met-haemoglobin.

Methaemoglobin undergoes a transition to a T-like form at acid pH in the presence of strong effectors such as inositol hexakisphosphate (IHP), as evidenced by spectroscopic and oxidation potential measurements. Since oxygen and CO do not bind to the ferric haems, it is difficult to compare the properties of the R-met and T-met forms with those of ferrous haemoglobin. We have therefore prepared 90% oxidized samples, where the dominant signal for ligand (oxygen or CO) binding is due to tetramers with three met haems. Measurements were made of the oxygen equilibrium curves and CO rebinding kinetics after photodissociation. Without effectors, the partially oxidized samples show mainly R-state properties. Addition of IHP at acid pH induces an increase in T-state behaviour, as indicated by a lower oxygen affinity and a higher fraction of the slow bimolecular component for CO rebinding.

Steric and hydrophobic determinants of the solubilities of recombinant sickle cell hemoglobins.

Models for the structure of the fibers of deoxy sickle cell hemoglobin (Hb Hb S, beta 6 Glu-->Val) have been obtained from X-ray and electron microscopic studies. Recent molecular dynamics calculations of polymer formation give new insights on the various specific interactions between monomers. Site-directed mutagenesis with expression of the Hb S beta subunits in Escherichia coli provides the experimental tools to test these models. For Hb S, the beta 6 Val residue is intimately involved in a specific lateral contact, at the donor site, that interacts with the acceptor site of an adjacent molecule composed predominantly of the hydrophobic residues Phe 85 and Leu 88. Comparing natural and artificial mutants indicates that the solubility of deoxyHb decreases in relation to the surface hydrophobicity of the residue at the beta 6 position with Ile > Val > Ala. We also tested the role of the stereospecific adjustment between the donor and acceptor sites by substituting Trp for Glu at the beta 6 location. Among these hydrophobic substitutions and under our experimental conditions, only Val and Ile were observed to induce polymer formation. The interactions for the Ala mutant are too weak whereas a Trp residue inhibits aggregation through steric hindrance at the acceptor site of the lateral contact. Increasing the hydrophobicity at the axial contact between tetramers of the same strand also contributes to the stability of the double strand. This is demonstrated by associating the beta 23 Val-->Ile mutation at the axial contact with either the beta 6 Glu-->Val or beta 6 Glu-->Ile substitution in the same beta subunit.(ABSTRACT TRUNCATED AT 250 WORDS)

Calpain controls the balance between protein tyrosine kinase and tyrosine phosphatase activities during platelet activation.

Protein phosphorylation was studied during platelet stimulation in two ranges of ionized [Ca2+]. At ionized [Ca2+]i< or = 1 microM, proteins were phosphorylated. At ionized [Ca2+]i > or = 4 microM, phosphoproteins disappeared. Protein dephosphorylation was prevented by the combined action of calpeptin and phosphatase inhibitors. Protein tyrosine phosphatase activity was stimulated regardless of the ionized [Ca2+] level. Protein tyrosine kinase activity was stimulated at ionized [Ca2+]i < or =1 microM, whereas at ionized [Ca2+]i > or =4 microM, no protein tyrosine kinase activity was observed except in the presence of calpeptin. Thus, the massive tyrosine phosphoprotein disappearance observed at a high ionized [Ca2+]i resulted not only in protein tyrosine phosphatase activation, but also in calpain-induced protein tyrosine kinase inactivation.

A new approach in the study of the molecular and cellular events implicated in heparin-induced thrombocytopenia. Formation of leukocyte-platelet aggregates.

Heparin-induced thrombocytopenia (HIT), a relatively common complication of heparin therapy, results of platelet activation, via the receptor for the Fc domain of IgG (FcgammaRIIa), by heparin-dependent-antibodies, commonly directed against the heparin-platelet factor 4 (H-PF4) antigenic complex. Our strategy was to use whole blood allowing the study of leukocyte-platelet interactions. Experiments were performed with blood from healthy donors incubated with HIT patients' plasma and different concentrations of heparin. We showed that 75% of the HIT patients' plasma induced the formation of leukocyte-platelet-aggregates in a heparin-dependent-manner. The formation of leukocyte-platelet-aggregates induced by HIT plasma in the presence of heparin was (i) independent of the healthy blood donor FcgammaRIIa polymorphism, (ii) correlated with the levels of anti H-PF4 IgG antibodies contained in the patients' plasma, and to a lesser extent to anti H-PF4 IgM antibodies, and (iii) was mediated by P-selectin. This report opens new prospects in the study of the molecular and cellular events implicated in HIT.

Thiosulfinates inhibit platelet aggregation and microparticle shedding at a calpain-dependent step.

Thiosulfinates (TSs) are sulfur compounds generated through the processing of different Allium species with antiplatelet property. To further define this platelet inhibitory effect we studied diallyl-TS (Al2TS), dipropyl-TS (Pr2TS). and dimethyl-TS (Me2TS) on platelet responses. The three TSs inhibited dose-dependent platelet aggregation, with IC50 values of 15+/-2, 19+/-2, and 9+/-1 microM for Al2TS, Pr2TS and Me2TS, respectively. TSs had no effect on the expression of a platelet procoagulant surface, measured by flow cytometry as the binding of annexin V-FITC. They inhibited the microparticle shedding and clot retraction. Since the microparticle shedding is a calpain-activation dependent step, we assessed calpain activation by analysis of autoproteolysis in shorter active forms and by talin proteolysis in the presence of TSs. Calpain activation was inhibited by TSs independently of fibrinogen binding. Thus, TSs represent a new category of platelet inhibitors, acting on calpain-induced events.

Platelets induce human umbilical vein endothelial cell proliferation through P-selectin.

We studied whether platelets could participate in the endothelial cell monolayer regeneration in the case of a vessel damage. Incorporation of [3H]-thymidine into the DNA of human umbilical vein endothelial cells (HUVECs) was measured after 48 h of co-incubation with platelets. The effect of platelets was compared to that of platelet-free supernatants from thrombin-activated platelets that had secreted their active granule constituents. Platelets dose-dependently induced HUVEC proliferation. Platelets preactivated by thrombin induced similar proliferation as did unactivated platelets (proliferation factor = 7 - 8), indicating that preactivation of platelets was not required. Platelets fixed with paraformaldehyde had no effect, suggesting that the platelet mitogenic effect required a mobile, alive membrane. Ketanserine and suramin reduced by at most 30 % the platelet-induced proliferation; supernatants of thrombin-activated platelets caused only minor proliferation (proliferation factor = 2), suggesting that secreted 5-hydroxytryptamine and growth factors poorly contributed to the proliferative effect. When the co-incubation was performed in the presence of an anti P-selectin antibody, the platelet-induced HUVEC proliferation was inhibited. The results suggest that platelet adhesion participate in the control of the endothelial regeneration and that platelet P-selectin is a molecular determinant of the proliferative signal.

[Evaluation of esophageal motility disorders triggered by ingestion of solids in the case of non-obstructive dysphagia]. / Evaluation des anomalies motrices oesophagiennes déclenchées par l'ingestion de solides en cas de dysphagie non obstructive.

UNLABELLED: The aim of this study was to define the normal manometric pattern of esophageal motility in response to food ingestion and to evaluate the contribution of esophageal manometry in the management of patients complaining of functional dysphagia. PATIENTS AND METHODS: Twenty-one healthy volunteers and 25 consecutive patients complaining of functional dysphagia with normal conventional esophageal manometry were included in this prospective study. An event marker was used to study the relationship between dysphagia and motility events. RESULTS: Twenty-two out of 25 patients (88%) reported dysphagia during esophageal manometry with food ingestion, while none complained of dysphagia during conventional esophageal manometry. Significantly, food ingestion induced in healthy volunteers and in patients: an increase in the amplitude and duration of esophageal body peristaltic contractions, and a decrease in their propagation speed; an increase in the basal pressure and a decrease in the relaxation percentage of the lower esophageal sphincter during deglutition. The percentage of solid swallows with one or several of the 7 abnormal motility patterns studied prospectively was significantly higher among patients (53.7%) than among healthy volunteers (4.3%) (P < 0.0001); it was also significantly higher among patients during swallows with dysphagia (70.1%) than without dysphagia (33.6%) (P < 0.0001). CONCLUSION: Esophageal manometry with food ingestion is an effective means of defining abnormal motility patterns and their relationship with dysphagia during functional dysphagia.

[Structural basis for the functional properties of hemoglobin (author's transl)]. / Bases structurales des propriétés fonctionnelles de l'hémoglobine.

Functional properties of tetrameric HbA are schematically described in this short review. After considering the various structures of the protein and its binding with heme, an attempt is made to explain the influence of this structure on the affinity of Hb for oxygen, cooperative binding of oxygen, and the alkaline Bohr effect. Fixation of erythrocytic anions (chlorine and 2,3 diphosphoglycerate) modulate certain intrinsic properties, allowing the Hb molecule to provide for efficacious transport of oxygen between the environment and the metabolically active tissues.

An adult case of acute biphenotypic leukemia with characteristic mixed morphology.

A case of acute biphenotypic leukemia with mixed blast morphology and combined myeloid and T-lymphoid features is reported. The leukemic cells consisted of small lymphoid hand-mirror blasts and large blasts with cytoplasmic granules and rare Auer rods. The cells expressed myeloid and immature T-lymphoid features by cytochemistry and immunophenotyping, however T cell receptor genes were in germline configuration. Cases of biphenotypic leukemia with similar morphological and immunophenotypic findings have been described previously in children. This case represents a morphologically and phenotypically distinct subtype of acute biphenotypic leukemia.

Are insulin analogues detemir or glulisine used preferentially in overweight/obese subjects? A German multicentre analysis of 38560 type 2 diabetic patients from the DPV registry.

OBJECTIVE: Several studies suggest benefits of insulin analogues detemir or glulisine in overweight and obese patients with type 2 diabetes. The present multicentre study therefore examines, whether these insulin analogues are used more frequently in patients with increased body mass index. METHODS: Data of 38 560 adult type 2 diabetic patients using insulin analogues, from 150 centres in Germany, registered in a standardized, prospective, computer-based documentation program (DPV), were included. Patients were classified into body mass index categories according to World Health Organization. Analysis was stratified by 3 time periods. To adjust for confounding effects, multivariable logistic regression models were created. RESULTS: Detemir was preferentially used in overweight (OR 1.36, 95%-CI 1.20-1.53) and obese patients (OR 2.06, 95%-CI 1.84-2.31) compared to normal-weight patients. These effects remained significant after adjusting for sex, age, new/old federal state of Germany, size of centre, treatment in university clinic and clinic/specialized private practice. Models were additionally adjusted for time period and interaction of BMI category with age or sex. For glulisine, a minor effect was present when comparing obese to normal-weight patients (OR 1.26, 95%-CI 1.06-1.50). After adjustment, this finding was no longer significant. Stratified by obesity grade, class III obese patients more frequently used detemir or glulisine compared to class I obese patients. Comparing time periods, odds ratios did not differ, neither for detemir nor for glulisine. CONCLUSION: Detemir is used more often in overweight and obese patients compared to normal-weight patients. For glulisine, the relationship is less pronounced.

Surgical strategies in patients with advanced hilar cholangiocarcinoma (Klatskin tumor).

BACKGROUND: Surgical resection represents the only potentially curative treatment for hilar cholangicarcinoma. Because of the aggressive nature and the absence of effective adjuvant therapy treatment remains still a challenge. DISCUSSION: This manuscript reviews management of hilar cholangiocarcinoma with a focus on operative strategy.

Altered PTEN function caused by deletion or gene disruption is associated with poor prognosis in rectal but not in colon cancer.

Colorectal cancer is the third most common malignancy worldwide. Anti-epidermal growth factor receptor (EGFR)-targeted therapy shows clinical evidence in this malignancy and improves outcome. The tumor suppressor gene phosphatase and tensin homologue (PTEN) is considered a potential predictor of nonresponse to anti-EGFR agents. The purpose of this study was to assess whether associations between PTEN alterations (PTEN gene deletion or PTEN gene disruption) and clinical outcome could be caused by a prognostic (and not predictive) effect of PTEN inactivation. Therefore, we analyzed 404 colorectal cancers not previously treated with anti-EGFR drugs in a tissue microarray format. PTEN deletion and PTEN gene rearrangements were analyzed by fluorescence in situ hybridization. Heterogeneity analysis of all available large tissue sections was performed in 6 cases with genomic PTEN alteration. Twenty-seven (8.8%) of 307 analyzable colorectal cancer spots showed genomic PTEN alterations including 24 hemizygous and 1 homozygous deletion as well as 2 PTEN gene disruptions. Genomic PTEN alterations were associated with reduced patient survival in rectal cancer in univariate and multivariate analyses (P = .012; hazard ratio, 2.675; 95% confidence interval, 1.242-5.759) but not in colon cancer. Large-section evaluation revealed a homogeneous distribution pattern in all 4 analyzed cases with PTEN deletion and in both cases with a PTEN gene disruption. In conclusion, genomic PTEN gene alterations caused by deletion or gene disruption characterize a fraction of rectal cancers with particularly poor outcome.