RNF2 regulates Wnt/ß-catenin signaling via TCF7L1 destabilization

The Wnt signaling pathway is a crucial regulator of various biological processes, such as development and cancer. The downstream transcription factors in this pathway play a vital role in determining the threshold for signaling induction and the length of the response, which vary depending on the biological context. Among the four transcription factors involved in canonical Wnt/ß-catenin signaling, TCF7L1 is known to possess an inhibitory function; however, the underlying regulatory mechanism remains unclear. In this study, we identified the E3 ligase, RNF2, as a novel positive regulator of the Wnt pathway. Here, we demonstrate that RNF2 promotes the degradation of TCF7L1 through its ubiquitination upon activation of Wnt signaling. Loss-of-function studies have shown that RNF2 consistently destabilizes nuclear TCF7L1 and is required for proper Wnt target gene transcription in response to Wnt activation. Furthermore, our results revealed that RNF2 controls the threshold, persistence, and termination of Wnt signaling by regulating TCF7L1. Overall, our study sheds light on the previously unknown degradation mechanism of TCF7L1 by a specific E3 ligase, RNF2, and provides new insights into the variability in cellular responses to Wnt activation.

How to prove neglect in the context of the post-mortem examination

Understanding the causes, extent, and period of neglect is not only a medical but also a forensic task when it comes to legal investigations. In this study, we evaluated 46 autopsied cases where there was clear evidence of physical neglect during the last period of the deceased's life. The age of the deceased ranged from 21 to 96 years; most of them were female (71.7%). The majority of cases (89.9%) took place in a domestic environment, with partners or relatives providing care. The most frequent post-mortem findings were pressure sores, followed by inflammatory skin changes, and signs of malnutrition and dehydration. Neglect was the cause or co-cause of death in 23% of the cases. More than half of the deceased showed severe contamination of the skin surface by excrement, and in almost 40% of the cases, fly infestation was found. The majority of insects belonged to the group of house flies (Diptera: Muscidae), mainly the common house fly, Musca domestica. By analyzing the entomological evidence, it was possible to prove an insect infestation period of at least several days ante-mortem. Since the period of neglect may be relevant in terms of legal proceedings, the present work demonstrates the particular importance of insect traces in providing this evidence. While prosecution and conviction of caregivers remain challenging, it is all the more essential that entomology and legal medicine collaborate on the analysis of findings of neglect.

Abschätzung des Thromboserisikos bei internistischen Patienten

Bei einem thromboembolischen Ereignis handelt es sich möglicherweise um eine vermeidbare Komplikation, wenn das Risiko prospektiv erkennbar ist. Die richtige Einschätzung des individuellen Risikos ist deshalb von herausragender klinischer Bedeutung, bei internistischen Patienten wegen der Komplexität und Multimorbidität älterer Patienten jedoch schwierig. Bei nicht chirurgischen Patienten ist das individuelle Thromboserisiko definiert als Summe aus expositionellen und dispositionellen Risikofaktoren, die nach evidenzbasierter Studienlage gewichtet und in ein Risikoschema umgesetzt werden. In ein praxisnahes und alltagstaugliches Risikoschema können nicht alle klinischen Situationen aufgenommen werden, jedoch erlauben die Schemata in dieser Arbeit die flexible Anwendung und Anpassung an die individuelle Patientensituation in Klinik und ambulanter Versorgung. Damit soll ermöglicht werden, dass der Arzt eine begründete Ja/Nein-Entscheidung zur Thromboseprophylaxe treffen kann.

[Barrett's esophagus and carcinoma: Recommendations of the S2k guideline 2014 and the S3 guideline 2015]

In the current S2k guideline for gastroesophageal reflux disease and the new S3 guideline for esophageal cancer, histopathological evaluation of Barrett's esophagus has been revised and supplemented. The histological diagnosis of Barrett's esophagus still requires the proof of a specialized intestinal metaplastic epithelium (columnar epithelium with goblet cells). Barrett mucosa must be classified as negative, unclear/doubtful, and positive concerning the intraepithelial neoplasia (IEN)/dysplasia according to the current WHO guideline. Each IEN should be confirmed by an external second opinion due to poor interobserver variability. The pathological classification is of decisive importance here, since the recommended monitoring intervals are based solely on the ground of proved IEN. Risk factors in endoscopic resection specimens such as depth of infiltration (m1-m4; sm1-sm3; distance in µm); angioinvasion (L, V); grading and lateral/basal resection margin have to be reported. In surgical specimens, the reference of the tumor center to the gastroesophageal junction and in the neoadjuvant situation the tumor regression should be documented.

Fibroblast activation protein-α, a stromal cell surface protease, shapes key features of cancer associated fibroblasts through proteome and degradome alterations

Cancer associated fibroblasts (CAFs) constitute an abundant stromal component of most solid tumors. Fibroblast activation protein (FAP) α is a cell surface protease that is expressed by CAFs. We corroborate this expression profile by immunohistochemical analysis of colorectal cancer specimens. To better understand the tumor-contextual role of FAPα, we investigate how FAPα shapes functional and proteomic features of CAFs using loss- and gain-of function cellular model systems. FAPα activity has a strong impact on the secreted CAF proteome ("secretome"), including reduced levels of anti-angiogenic factors, elevated levels of transforming growth factor (TGF) β, and an impact on matrix processing enzymes. Functionally, FAPα mildly induces sprout formation by human umbilical vein endothelial cells. Moreover, loss of FAPα leads to a more epithelial cellular phenotype and this effect was rescued by exogenous application of TGFβ. In collagen contraction assays, FAPα induced a more contractile cellular phenotype. To characterize the proteolytic profile of FAPα, we investigated its specificity with proteome-derived peptide libraries and corroborated its preference for cleavage carboxy-terminal to proline residues. By "terminal amine labeling of substrates" (TAILS) we explored FAPα-dependent cleavage events. Although FAPα acts predominantly as an amino-dipeptidase, putative FAPα cleavage sites in collagens are present throughout the entire protein length. In contrast, putative FAPα cleavage sites in non-collagenous proteins cluster at the amino-terminus. The degradomic study highlights cell-contextual proteolysis by FAPα with distinct positional profiles. Generally, our findings link FAPα to key aspects of CAF biology and attribute an important role in tumor-stroma interaction to FAPα.

Unexpected toxicity (UT) and opportunistic infections (OI) after rituximab-containing therapy for non-Hodgkin's lymphoma (NHL)

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Background: Rituximab (R) is increasingly used for the treatment of B-NHL. Most adverse events are mild to moderate. In rare cases, however, R may be associated with severe UT and OI. Methods: The records of consecutive pts treated at 2 institutions from 01/06 to 12/08 with R-containing chemotherapy or R-maintenance therapy (R-M) for NHL were analyzed for severe UT and OI. UT was considered as related to R if it could not be explained otherwise. Results: 99 pts were included in the cohort study. Pts received a median of 6 cycles (range 1 - 18) of R. A total of 517 cycles of R were evaluable for OI or UT. 7 of 99 pts (7%) (2 females, 5 males) with a median age of 69.5 yrs (range 41–76) experienced UT (n=4) or OI (n=3). UT consisted of interstitial pneumonitis (IP) in 2 pts after 8 and 6 cycles of R-CHOP for diffuse large cell lymphoma (DLCL), a case of congestive heart failure (NYHA III°) after 6x R-CHOP + 2x R-M for follicular lymphoma (FL) and a case of grade 4 pancytopenia lasting for 22 days following 2x R-FC for chronic lymphocytic leukemia. IP completely resolved after initiation of prednisone (n=1) or under empiric antimicrobial therapy (n=1). Congestive heart failure improved under appropriate therapy and the pt received 2 more cycles of R-M. Pancytopenia slowly recovered under therapy with G-CSF, R was terminated. OI consisted of pneumocystis jirovecii pneumonia after 5x R-CHOP-14 for DLCL, Epstein-Barr-virus (EBV)-associated hepatitis after 5x R-CHOP-21 for relapsed FL and generalized herpes zoster following 6x R-bendamustine (RB) + 1x R-M for recurrent BALT-lymphoma. R was restarted in the latter 2 pts. Infections resolved under antimicrobial therapy. EBV-hepatitis improved spontaneously. Moreover, 2 pts were transferred to us for therapy of enterovirus-induced encephalitis after 6x R-CHOP-21 + 2x R-M for FL (n=1) and cerebral toxoplasmosis in a pt heavily pretreated with R-containing therapy for relapsed mantle cell lymphoma (n=1). Conclusions: Severe UT and OI are rare but potentially fatal complications. Awareness of UT/OI, rapid diagnostic proceedings and, whenever possible, initiation of therapy are essential. In selected cases reexposure of R may be feasible.

No significant financial relationships to disclose.

Hematopoietic stem cell transplantation (HSCT) in patients with primary granulocytic sarcoma (GS)

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Background: GS preceding acute myeloid leukemia (AML) is extremely rare and the prognosis is poor. Patients usually undergo systemic chemotherapy (CT) but the role of HSCT is not sufficiently defined. Methods: We report on 3 cases of non-leukemic GS, all of those treated with inductive CT followed by either autologous or allogeneic SCT. Furthermore, the literature on the role of HSCT in GS is reviewed. Results: Case 1: A 55-year-old man presented with a mediastinal mass and right pleural effusion. Fluid cytology revealed hematopoietic cells. Mediastinoscopy showed GS but peripheral blood and bone marrow were free of blasts. He underwent 2 cycles of anthracyline-cytarabine (AC) containing induction CT followed by myeloablative conditioning and autologous SCT in 1st remission. Radiotherapy to the mediastinum was applied afterwards. He remained in CR for 6 months when a leukemic relapse was diagnosed. He is currently undergoing reinduction CT and will proceed to receive an unrelated donor (URD) SCT. Case 2: A 51-year old man was diagnosed with GS of the right testicle. After orchiectomy he was followed by observation only. 8 months later a leukemic relapse [karyotype 46 XY, del (9)(q22), der(13) t(8;13)] occurred. The patient received 2 courses of AC-based induction CT followed by myeloablative conditioning and an HLA-matched URD transplant in 1st CR. However, 27 months after HSCT another leukemic relapse was diagnosed. He received a 2nd URD transplant but died of severe graft versus host disease (GvHD) and veno-occlusive disease 10 weeks later. Case 3: A 37 year-old woman was diagnosed with non-leukemic GS located at multiple bone sites. She underwent 4 courses of AC-containing CT resulting in a CR. 6 months later she presented with multiple recurrent GS confined to the skeleton. She received myeloablative conditioning followed by an allogeneic SCT from her HLA-mismatched brother. Another CR was attained. However, she suffered from severe GvHD and died of severe sepsis 3 months after HSCT. Conclusions: The outcome of patients with primary GS appears to be poor even after treatment with HSCT. However, allogeneic SCT has curative potential as indicated by some cases of successful transplants reported in the literature.

No significant financial relationships to disclose.

Breakthrough pain characteristics and syndromes in patients with cancer pain. An international survey

Breakthrough pain (BKP) is a transitory flare of pain that occurs on a background of relatively well controlled baseline pain. Previous surveys have found that BKP is highly prevalent among patients with cancer pain and predicts more severe pain, pain-related distress and functional impairment, and relatively poor quality of life. An international group of investigators assembled by a task force of the International Association for the Study of Pain (IASP) evaluated the prevalence and characteristics of BKP as part of a prospective, cross-sectional survey of cancer pain. Fifty-eight clinicians in 24 countries evaluated a total of 1095 patients with cancer pain using patient-rated items from the Brief Pain Inventory (BPI) and observer-rated measures. The observer-rated information included demographic and tumor-related data, the occurrence of BKP, and responses on checklists of pain syndromes and pathophysiologies. The clinicians reported BKP in 64.8% of patients. Physicians from English-speaking countries were significantly more likely to report BKP than other physicians. BKP was associated with higher pain scores and functional interference on the BPI. Multivariate analysis showed an independent association of BKP with the presence of more than one pain, a vertebral pain syndrome, pain due to plexopathy, and English-speaking country. These data confirm the high prevalence of BKP, its association with more severe pain and functional impairment, and its relationship to specific cancer pain syndromes. Further studies are needed to characterize subtypes of BKP. The uneven distribution of BKP reporting across pain specialists from different countries suggests that more standardized methods for diagnosing BKP are needed.

Sneddon's syndrome: a case report

We report a case of Sneddon's syndrome with the triad of livedo reticularis, hypertension, and neurologic symptoms. The procedures for diagnosis and the tests to delineate clotting abnormalities are examined.

Efficacy of systemic administration of irinotecan against neuroblastoma xenografts

The efficacy of the topoisomerase I inhibitor 7-ethyl-10-(4-[1-piperidino]-1-piperidino)-carbonyloxy-camptotheci n (irinotecan, CPT-11) has been examined against a panel of six independently derived neuroblastoma xenografts. Intensive courses of therapy, where irinotecan was administered i.v. daily 5 days per week for two consecutive weeks [(dx5)2; defined as 1 cycle], were compared to more protracted low-dose schedules where cycles were repeated every 21 days for a total of three courses ¿abbreviated [(dx5)2]3¿. When administered (dx5)2 for a single cycle, the maximum tolerated daily dose was 40 mg/kg. Irinotecan induced a high frequency of complete regressions (CRs) in four of the six lines examined; however, most tumors achieving CR regrew during the period of observation (12 weeks). Furthermore, there was no advantage in high-dose regimens as compared to low dose (10 mg/kg) on the same schedule. Protracted schedules of administration, where three courses of therapy were given at 21-day intervals ¿[(dx5)2]3¿ i.v. were examined at 10 and 5 mg/kg/dose. Even at the lower dose level, irinotecan caused 100% CR in all tumor lines that were maintained at 12 weeks. To determine the minimum dose levels required to induce objective regressions of neuroblastoma xenografts, decreasing doses were examined using the [(dx5)2]3 i.v. schedule. At 2.5 mg/kg/dose, >90% of NB-1643, NB-1691, NB-1382.2, and NB-EB xenografts demonstrated CR, whereas at 1.25 mg/kg/dose, all six tumor lines evaluated demonstrated objective regressions (>/=50% volume reduction), with a high frequency of CRs in four tumor lines. The 10-hydroxy-7-ethyl CPT lactone single-day systemic exposure measured with the minimum dose (2.5 mg/kg) associated with complete response was 198, 257, and 228 ng.h/ml for mice bearing NB-1643, NB-1691, and NB-EB tumors, respectively. These results indicate that childhood neuroblastoma xenografts are highly sensitive to irinotecan given by parenteral administration, and that efficacy is schedule dependent.

Evaluation of irinotecan in combination with 5-fluorouracil or etoposide in xenograft models of colon adenocarcinoma and rhabdomyosarcoma

Irinotecan [7-ethyl-10-(4-[1-piperidino]-1-piperidino)-carbonyloxy-camptothec in] administered i.v. in two courses, each course consisting of administration every day for 5 days [(dx5)2] on days 1-5 and 8-12, has demonstrated significant activity against advanced human tumor xenografts derived from colon adenocarcinomas and several childhood cancers. To build on this therapy, we have evaluated the combination of irinotecan given on this schedule with 5-fluorouracil given on days 1, 7, and 14 with or without leucovorin [(dx5)3 i.v.] against colon tumors, or combined with etoposide administered (dx5)2 i.v. either 2 h before or 2 h after irinotecan for treatment of colon tumors and rhabdomyosarcomas. A combination of 5-fluorouracil at 75% and irinotecan at 50% of their respective maximum tolerated doses when administered as single agents on this schedule gave acceptable toxicity. Against colon adenocarcinoma xenografts, 5-fluorouracil did not enhance the response rate compared with that obtained with the optimum dose of irinotecan given as a single agent. Against GC3/TK- xenografts, which lack thymidine kinase and cannot salvage thymidine to circumvent the inhibition of thymidylate synthase, the addition of leucovorin to the combination increased the complete response rate from 10 to >90%, whereas the response rates for the optimal doses of irinotecan or 5-fluorouracil, as single agents, were 30 and <10%, respectively. Etoposide d x 5 i.v. for two or three courses or (d x 5)3 p.o. did not cause objective regression of any colon tumors. In contrast, three of five rhabdomyosarcoma lines demonstrated a high frequency of partial regressions or complete regressions when treated (d x 5)1 i.v. Repetitive courses [e.g., (d x 5)2 or (d x 5)3] i.v. or p.o. or by 4-h infusion d x3 i.v. were either equally effective or less effective. Irinotecan and etoposide were combined using the (d x 5)2 i.v. schedule for both drugs, in which irinotecan was given 2 h before or 2 h after the administration of etoposide. Each drug could be combined at only 38% of its respective maximum tolerated dose when administered as a single agent, indicating greater than additive toxicity. Toxicity was similar irrespective of the sequence of administration and was manifested by loss of weight (73% of the initial weight, nadir day 7), myelosuppression, and prolonged thrombocytopenia. The responses of colon carcinomas to the combination given in either sequence were similar to that achieved with irinotecan given alone at the same dose as used in the combination. Similarly, when etoposide was given before irinotecan, the responses of rhabdomyosarcomas were similar to those for irinotecan. However, in experiments in which etoposide was administered 2 h after each dose of irinotecan, there was significant antagonism of the antitumor activity of irinotecan.

Efficacy of topoisomerase I inhibitors, topotecan and irinotecan, administered at low dose levels in protracted schedules to mice bearing xenografts of human tumors

The efficacy of protracted schedules of therapy of the topoisomerase I inhibitors 9-dimethyl-aminomethyl-10-hydroxycamptothecin (topotecan) and 7-ethyl-10-[4-(1-piperidino)-1-piperidino]-carbonyloxycamptothecin (irinotecan; CPT-11) were evaluated against a panel of 21 human tumor xenografts derived from adult and pediatric malignancies. Tumors included eight colon adenocarcinomas, representing an intrinsically chemorefractory malignancy, six lines derived from childhood rhabdomyosarcoma (three embryonal, three alveolar) representing a chemoresponsive histiotype, sublines of rhabdomyosarcomas selected in vivo for resistance to vincristine and melphalan, and three pediatric brain tumors. All tumors were grown at the subcutaneous site. Topotecan was administered by oral gavage 5 days per week for 12 consecutive weeks. The maximum tolerated dose (MTD) was 1.5 mg/kg per dose. Irinotecan was given by i.v. administration daily for 5 days each week for 2 weeks [(d x 5)2](one cycle of therapy), repeated every 21 days. The MTD for three cycles was 10 mg/kg per dose. Treatment was started against advanced tumors. Topotecan caused a high frequency of objective regressions in one of eight colon tumor lines, whereas irinotecan caused complete regressions (CR) of all tumors in three colon lines and a high frequency of CRs in three additional lines. Both drugs demonstrated similar activity against rhabdomyosarcoma xenografts. Topotecan caused CR of all tumors in four of six lines, and irinotecan in five of six lines evaluated. Both agents retained full activity against tumors selected for primary resistance to vincristine, but only irinotecan retained activity against a tumor selected for primary resistance to melphalan. Both agents demonstrated good activity against brain tumor xenografts with irinotecan causing CR in two of three lines and topotecan inducing CR in one of three lines. Results indicate that low-dose protracted schedules of daily administration of these topoisomerase I inhibitors is either equi-effective or more efficacious than more intense shorter schedules of administration reported previously.

Efficacy of sulofenur and a second generation diarylsulfonylurea, N-[5-(2,3-dihydrobenzofuryl)sulfonyl]-N'-(3,4-dichlorophenyl)urea (LY295501), against colon adenocarcinoma xenografts

Sulofenur and a second generation diarylsulfonylurea (DSU), N-[5-(2,3-dihydrobenzofuryl)sulfonyl]-N'-(3,4-dichlorophenyl)urea (LY295501), were evaluated against a panel of eight colon adenocarcinoma xenografts. Of these tumors, four were derived from adult patients and four from young patients (age range 11-26 years). Both drugs were administered twice daily by oral gavage, 5 days each week for two or three consecutive weeks. The maximum tolerated dose for sulofenur was 300 mg/kg/dose for three courses and 200 mg/kg/dose for LY295501. Against 'adult' derived tumors, sulofenur caused a high proportion of objective regressions of advanced xenografts in two of four lines, with significant inhibition of growth in three tumor lines. Colon adenocarcinomas from young patients were similarly sensitive to sulofenur with a high proportion of complete and partial responses in two of three lines. LY295501 demonstrated a very similar spectrum of activity against this panel of xenografts. Tumors intrinsically resistant to sulofenur were resistant to LY295501, although this agent was slightly more active than sulofenur against tumors from younger patients. In addition, xenografts were established from a cloned colon adenocarcinoma line (GC3/c1) and its derivative GC3/LYC5) selected in vitro for resistance to sulofenur. GC3/c1 xenografts were highly responsive to both sulofenur and LY295501, whereas GC3/LYC5 xenografts were completely resistant to both agents administered at the maximum tolerated dose and schedule. These results indicate that the second generation DSU, LY295501, demonstrates a similar spectrum of activity against colon tumors as does sulofenur, and that the mechanism of action and/or resistance to the two drugs is probably similar.