Transient loss of Polycomb components induces an epigenetic cancer fate.

Although cancer initiation and progression are generally associated with the accumulation of somatic mutations1,2, substantial epigenomic alterations underlie many aspects of tumorigenesis and cancer susceptibility3-6, suggesting that genetic mechanisms might not be the only drivers of malignant transformation7. However, whether purely non-genetic mechanisms are sufficient to initiate tumorigenesis irrespective of mutations has been unknown. Here, we show that a transient perturbation of transcriptional silencing mediated by Polycomb group proteins is sufficient to induce an irreversible switch to a cancer cell fate in Drosophila. This is linked to the irreversible derepression of genes that can drive tumorigenesis, including members of the JAK-STAT signalling pathway and zfh1, the fly homologue of the ZEB1 oncogene, whose aberrant activation is required for Polycomb perturbation-induced tumorigenesis. These data show that a reversible depletion of Polycomb proteins can induce cancer in the absence of driver mutations, suggesting that tumours can emerge through epigenetic dysregulation leading to inheritance of altered cell fates.

3-O sulfation of syndecan-1 mediated by the sulfotransferase HS3ST3a1 enhances myeloma aggressiveness.

Multiple myeloma is a hematological neoplasm derived from plasma cells invariably developing in the bone marrow (BM). The persisting clinical challenge in MM resides in its high ability to resist drugs as shown by the frequent relapses observed in patients regardless of the treatment applied. In a mouse model of MM, we identified a subpopulation of cells harboring increased resistance to current MM drugs. These cells bound a proliferation inducing ligand (APRIL), a key MM promoting/survival factor. APRIL binding involved the heparan sulfate (HS) chain present on syndecan-1 (SDC-1), and correlated with reactivity to the anti-HS antibody 10e4. 10e4+cells had a high proliferation activity, and were able to form colonies in 3-D cultures. 10e4+ cells were the only cells able to develop in BM after intravenous injection. They also resisted drugs in vivo, since their number increased after treatment in BM. Notably, 10e4+ cells differentiated into 10e4- cells upon in vitro and in vivo expansion. Expression of one sulfotransferase, HS3ST3a1, allowed modification of syndecan-1 to confer reactivity to 10e4 and binding to APRIL. HS3ST3a1 deletion inhibited tumorigenesis in BM. Notably, the two populations coexisted at a variable frequency in the BM of MM patients at diagnosis. In total, our results indicate that 3-O-sulfation on SDC-1 carried out by HS3ST3a1 defines aggressive MM cells, and that targeting of this enzyme could possibly be used to better control drug resistance.

RECQ1 helicase is involved in replication stress survival and drug resistance in multiple myeloma.

Multiple myeloma (MM) is a plasma cell cancer with poor survival, characterized by the expansion of multiple myeloma cells (MMCs) in the bone marrow. Using a microarray-based genome-wide screen for genes responding to DNA methyltransferases (DNMT) inhibition in MM cells, we identified RECQ1 among the most downregulated genes. RecQ helicases are DNA unwinding enzymes involved in the maintenance of chromosome stability. Here we show that RECQ1 is significantly overexpressed in MMCs compared to normal plasma cells and that increased RECQ1 expression is associated with poor prognosis in three independent cohorts of patients. Interestingly, RECQ1 knockdown inhibits cells growth and induces apoptosis in MMCs. Moreover, RECQ1 depletion promotes the development of DNA double-strand breaks, as evidenced by the formation of 53BP1 foci and the phosphorylation of ataxia-telangiectasia mutated (ATM) and histone variant H2A.X (H2AX). In contrast, RECQ1 overexpression protects MMCs from melphalan and bortezomib cytotoxicity. RECQ1 interacts with PARP1 in MMCs exposed to treatment and RECQ1 depletion sensitizes MMCs to poly(ADP-ribose) polymerase (PARP) inhibitor. DNMT inhibitor treatment results in RECQ1 downregulation through miR-203 deregulation in MMC. Altogether, these data suggest that association of DNA damaging agents and/or PARP inhibitors with DNMT inhibitors may represent a therapeutic approach in patients with high RECQ1 expression associated with a poor prognosis.

[Does consumption of tobacco, alcohol, and cannabis in adolescents and young adults with cancer affect the use of analgesics during hospitalizations?]. / La consommation de tabac, alcool et cannabis chez les adolescents et jeunes adultes atteints de cancer a-t-elle un impact sur l'utilisation hospitalière des traitements antalgiques pendant la période de traitement ?

INTRODUCTION: The specificities of adolescents and young adults (AYAs) aged 15-25 years with cancer are now well recognized. Dedicated care was initiated in 2012 in France under the leadership of the INCa (National Cancer Institute). Research on supportive care and particularly pain management are still rare. This study aimed to evaluate the consumption of toxic substances (tobacco, cannabis, alcohol) in AYAs with cancer as well as its progression during the month following the diagnosis and to analyze its influence on opioid analgesic prescriptions during treatment. METHODS: This is a prospective study including all new patients aged 15-25 years in two centers between January and June 2013. Data on consumption of psychoactive substances were obtained during an individual interview with a questionnaire. National surveys were used to compare this cohort with the general population. Data on opioid treatments were collected from the computerized prescription software and computerized patient record. RESULTS: Thirty-seven AYAs were eligible and 30 were included; 67% of them were male and the median age was 18.7 years. The questionnaire on tobacco, alcohol, and cannabis consumption at diagnosis was well accepted. Consumption profiles were comparable to the general population. Changes in behavior were observed during the 1st month after diagnosis, with a decrease or cessation of consumption, particularly among young people. This study showed differences in the use and requirements for opioid analgesics during hospitalization according to these consumption data. CONCLUSION: Prevention and support for AYAs who are regular consumers of toxic substances must be organized during initial care in oncology.

Gene expression-based prediction of myeloma cell sensitivity to histone deacetylase inhibitors.

BACKGROUND: Multiple myeloma (MM) is still a fatal plasma cell cancer. Novel compounds are currently clinically tested as a single agent in relapsing patients, but in best cases with partial response of a fraction of patients, emphasising the need to design tools predicting drug efficacy. Histone deacetylase inhibitors (HDACi) are anticancer agents targeting epigenetic regulation of gene expression and are in clinical development in MM. METHODS: To create a score predicting HDACi efficacy, five MM cell lines were treated with trichostatin A (TSA) and gene expression profiles were determined. RESULTS: The expression of 95 genes was found to be upregulated by TSA, using paired supervised analysis with Significance Analysis of Microarrays software. Thirty-seven of these 95 genes had prognostic value for overall survival in a cohort of 206 newly diagnosed MM patients and their prognostic information was summed up in a histone acetylation score (HA Score); patients with the highest HA Score had the shorter overall survival. It is worth noting that MM cell lines or patients' primary MM cells with a high HA Score had a significant higher sensitivity to TSA, valproic acid, panobinostat or vorinostat. CONCLUSION: In conclusion, the HA Score allows identification of MM patients with poor survival, who could benefit from HDACi treatment.

Efficient transduction of healthy and malignant plasma cells by lentiviral vectors pseudotyped with measles virus glycoproteins.

A lot of genes deregulated in malignant plasma cells (PCs) involved in multiple myeloma have been reported these last years. The expression of some of these genes is associated with poor survival. A critical step is to elucidate the biological mechanisms triggered by these gene products. Such studies are hampered by the difficulty to obtain malignant PCs and to genetically modify them. Usual lentiviral vectors (LVs) pseudotyped with vesicular stomatitis virus envelope glycoprotein poorly transduced healthy and malignant PCs. Here, we report that LVs pseudotyped with the hemagglutinin and fusion glycoproteins from the measles Edmonston strain (H/F-LVs) can efficiently and stably transduce healthy and primary malignant PCs, without modifying their main phenotypic characteristics. Both LV pseudotypes efficiently transduced human myeloma cell lines. Importantly, both healthy and malignant PCs expressed CD46 and SLAMF1/CD150 membrane proteins, which are critical receptors for binding and productive genetic modification by H/F-LVs. The ability to efficiently introduce and express a given gene into PCs opens the possibility to study in detail PC biology.

Atacicept in relapsed/refractory multiple myeloma or active Waldenström's macroglobulinemia: a phase I study.

BACKGROUND: Advanced multiple myeloma (MM) and Waldenström's macroglobulinemia (WM) are incurable B-cell malignancies. This is the first full clinical report of atacicept, a fusion protein that binds to and neutralises the B-cell survival factors, B-lymphocyte stimulator (BLyS) and A proliferation-inducing ligand (APRIL), in MM and WM. METHODS: In this open-label phase-I study, 16 patients with advanced disease (12 MM, 4 WM) received one cycle of five once-weekly subcutaneous injections of atacicept (2, 4, 7 or 10 mg kg(-1)). Patients with stable disease after cycle 1 entered an extension study (either two additional cycles (2, 4 and 7 mg kg(-1) cohorts) or 15 consecutive weekly injections of atacicept 10 mg kg(-1)). RESULTS: Atacicept was well tolerated, systemically and locally; the maximum tolerated dose was not identified. Of 11 patients with MM who completed initial treatment, five patients were progression-free after cycle 1 and four patients were progression-free after extended therapy. Of four patients with WM, three patients were progression-free after cycle 1. Consistent with atacicept's mechanism of action, polyclonal immunoglobulin isotypes and total B cells were reduced. Bone-marrow density, myeloma cell numbers and plasma concentrations of soluble CD138 also decreased. CONCLUSION: Atacicept is well tolerated in patients with MM and WM, and shows clinical and biological activity consistent with its mechanism of action.

Bone morphogenic protein 6: a member of a novel class of prognostic factors expressed by normal and malignant plasma cells inhibiting proliferation and angiogenesis.

Pathogenesis of multiple myeloma is associated with an aberrant expression of pro-proliferative, pro-angiogenic and bone-metabolism-modifying factors by malignant plasma cells. Given the frequently long time span from diagnosis of early-stage plasma cell dyscrasias to overt myeloma and the mostly low proliferation rate of malignant plasma cells, we hypothesize these to similarly express a novel class of inhibitory factors of potential prognostic relevance. Bone morphogenic proteins (BMPs) represent possible candidates as they inhibit proliferation, stimulate bone formation and have an effect on the survival of cancer patients. We assessed the expression of BMPs and their receptors by Affymetrix DNA microarrays (n=779) including CD138-purified primary myeloma cell samples (n=635) of previously untreated patients. BMP6 is the only BMP expressed by malignant and normal plasma cells. Its expression is significantly lower in proliferating myeloma cells, myeloma cell lines or plasmablasts. BMP6 significantly inhibits the proliferation of myeloma cell lines, survival of primary myeloma cells and in vitro angiogenesis. A high BMP6 expression in primary myeloma cell samples delineates significantly superior overall survival for patients undergoing high-dose chemotherapy independent of conventional prognostic factors (International Staging System (ISS) stage, beta(2) microglobulin).

Heparan sulphate proteoglycans are essential for the myeloma cell growth activity of EGF-family ligands in multiple myeloma.

The epidermal growth factor (EGF)/EGF-receptor (ErbB1-4) family is involved in the biology of multiple myeloma (MM). In particular, ErbB-specific inhibitors induce strong apoptosis of myeloma cells (MMC) in vitro. To delineate the contribution of the 10 EGF-family ligands to the pathogenesis of MM, we have assessed their expression and biological activity. Comparing Affymetrix DNA-microarray-expression-profiles of CD138-purified plasma-cells from 65 MM-patients and 7 normal individuals to those of plasmablasts and B-cells, we found 5/10 EGF-family genes to be expressed in MMC. Neuregulin-2 and neuregulin-3 were expressed by MMC only, while neuregulin-1, amphiregulin and transforming growth factor-alpha were expressed by both MMC and normal plasma-cells. Using real-time polymerase chain reaction, we found HB-EGF, amphiregulin, neuregulin-1 and epiregulin to be expressed by cells from the bone marrow-environment. Only the EGF-members able to bind heparan-sulphate proteoglycans (HSPGs) - neuregulin-1, amphiregulin, HB-EGF - promote the growth of MMC. Those ligands strongly bind MMC through HSPGs. The binding and the MMC growth activity was abrogated by heparitinase, heparin or deletion of the HS-binding domain. The number of HS-binding EGF ligand molecules bound to MMC was higher than 10(5) molecules/cell and paralleled that of syndecan-1. Syndecan-1, the main HSPG present on MM cells, likely concentrates high levels of HS-binding-EGF-ligands at the cell membrane and facilitates ErbB-activation. Altogether, our data further identify EGF-signalling as promising target for MM-therapy.

Lymphocytes of dogs immunised with purified excreted-secreted antigens of Leishmania infantum co-incubated with Leishmania infected macrophages produce IFN gamma resulting in nitric oxide-mediated amastigote apoptosis.

The role of nitric oxide (NO) in the anti-leishmanial activity has been confirmed both in vitro and in vivo. Recently, we demonstrated that NO-mediated apoptosis-like amastigote death pathway is an important and highly regulated mechanism used for the clearance of Leishmania within infected murine macrophages stimulated to produce NO endogenously. To further characterize these important effector mechanisms in dog, a natural host-reservoir of L. infantum/L. chagasi, we have developed an ex vivo infection model of canine macrophages. Exposure of L. infantum-infected macrophages to autologous peripheral lymphocytes derived from dogs immunised with purified excreted-secreted antigens of L. infantum promastigotes (LiESAp) formulated with muramyl dipeptide (MDP) as adjuvant resulted in a significant leishmanicidal effect due to interferon (IFN)-gamma dependent macrophage activation. Concomitant accumulation of NO(3)(-)/NO(2)(-) in supernatants of co-cultured cells and in situ staining of parasites with terminal deoxynucleotidyltransferase-mediated dUTP nick-end labelling (TUNEL) and YOPRO-1 showed that NO-mediated apoptosis of intracellular L. infantum amastigotes is occurring in canine macrophages as previously observed in mouse models. Monitoring these parameters in dogs after immunisation and before experimental challenge can represent a useful and easy way to rapidly evaluate vaccine candidates against canine visceral leishmaniasis.

[Diaphragmatic hernias in adults]. / Hernies diaphragmatiques chez l'adulte.

The sliding hiatal hernias are the most usual diaphragmatic hernias in adults. Their recognition and the survey of their complications are performed with esophagoscopy. Antisecretory drugs are efficient in case of esophagitis. Indications for surgery are discussed in young patients with a long-term medical treatment. The paraesophagal hernias even with a total intrathoracic volvulus of the stomach are operated through abdominal approach. The Morgagni hernias are uncommon and rarely symptomatic. The Bochdaleck hernias are exceptionally revealed at adult age. Traumatic hernias occur after penetrating injury or blunt diaphragmatic rupture in automobile accident victims. Association of serious injuries and difficulty to identify the diaphragmatic injury may explain the delay in the diagnosis. Optimal management consists of early repair of the diaphragmatic injury through an abdominal approach, to avoid strangulation of the herniated organs.

[Carcinoid tumors and neuroendocrine carcinomas of the stomach. Prognosis and therapeutic management. Study of 6 cases]. / Les tumeurs carcinoïdes et carcinomes neuro-endocrines de l'estomac. Pronostic et conduite thérapeutique. Etude de six observations.

UNLABELLED: The six reported cases were separated into 2 groups: 1) the tumors of sporadic type, carcinoids (n = 2) and neuro-endocrine carcinomas (n = 2); 2) the gastrin-promoted tumors (n = 2). The purpose of this retrospective study was to review for each group of tumors, the clinicopathologic characteristics, prognosis factors and optimal management. In the first group, patients with a small and well differentiated tumor revealed by digestive bleeding, were treated by wedge excision and are alive and well 24 and 22 years later; the patients with large, invasive and poorly differentiated tumors were treated by subtotal (n = 1) and total (n = 1) gastrectomy, and died 1 year and 3 years later with metastases. In the second group, one patient with a small asymptomatic carcinoid tumor revealing chronic atrophic gastritis, was treated by endoscopic resection, without recurrence 3 years later; another patient with asymptomatic multifocal carcinoid tumors (about 100) associated with Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1, was treated by total gastrectomy and is alive and well 7 years later. No patient had carcinoid syndrome. Synaptophysin was the most sensitive marker and secretion of serotonine was detected in 2 tumors. CONCLUSION: Sporadic carcinoids serotonin and neuro-endocrine carcinomas are life-threatening tumors and need aggressive surgical therapy: their prognosis depends on tumors size, histological differentiation and mostly on tumor extension. In contrast, gastrin-promoted carcinoids do not result in disseminated disease and death, and a rather conservative approach seems appropriate.

[Diagnostic pitfalls of complicated colonic diverticulosis]. / Pièges diagnostiques de la diverticulose colique compliquée.

Irritable bowel syndrome and (or) non complicated diverticulosis, associated with fever, could simulate diverticulitis. Cancer of the sigmoid colon appears the main differential diagnosis, when diverticulitis is associated with an atypical or complete colonic stenosis on opaque enema, with a vesicoenteric fistula or with a peritonitis due to a colonic perforation. Even at laparotomy, a pseudotumoral diverticulitis cannot easily be differentiated from a colonic carcinoma. Acute diverticulitis of the caecum or ascending colon is usually mistaken for acute appendicitis. When massive and life-threatening bleeding occurs, the diverticular origin is difficult to assess. Bleeding due to peptic ulcer disease and thermometric ulceration being precluded, arteriography performed on emergency is necessary to differentiate between diverticular bleeding and angiodysplasia.

Traditional surgical management of common bile duct stones: a prospective study during a 20-year experience.

PURPOSE: To analyze the operative findings and evaluate the hospital morbidity and mortality. This experience is documented in order to provide a basis for comparison with therapeutic alternatives. PATIENTS AND METHODS: Prospective data were collected on 579 patients who underwent elective (n = 443) or emergent (n = 136) operations between 1970 and 1990. Their mean age was 60.1 years. Prior biliary symptoms were present in 96% and suggestive of choledocholithiasis in 69%. Acute pancreatitis was associated in 3%. RESULTS: Cholecystectomy was performed with intraoperative cholangiography in 85% of cases. Stones were extracted via the cystic duct in 18%, through a choledochotomy in 79%, and through an additional sphincterotomy in 3%. Cholangioscopy has been routinely used since 1977. The incidence of extraction of the stones via the cystic duct increased and the incidence of biliary-enteric bypass decreased significantly during the second decade. Complications occurred in 24.5% of the patients. General complications were significantly fewer in the second decade than in the first (6% versus 15%). The main biliary complications were related to biliary tubes (5%) and retained stones (5%). Ten patients (2%) required early reoperation. The overall mortality rate was 0.3%. Mortality was 1.4% after emergency operations and zero after elective operations and in patients under 60 years of age. The mean stay was 16.6 +/- 7.2 days, decreasing with time. CONCLUSION: Traditional open surgery is an effective and safe option for the management of cholelithiasis with choledocholithiasis. The choice between open surgery, laparoscopic surgery, and endoscopic sphincterotomy should be made for each patient according to the local availability and efficacy of these methods.

[Current aspects of stomach cancer. Surgical experience]. / Aspects actuels du cancer de l'estomac. Expérience chirurgicale.

The incidence of gastric carcinoma is variable through the world. This incidence has significantly decreased during recent decades, in France and in industrialized countries. The decline of gastric carcinoma is attributable to changes in the living habits and mostly to preservation of foodstuffs by refrigeration; it is explained by the decrease in number of intestinal or differentiated histologic type carcinomas according to the Lauren's classification; on the contrary, diffuse or poorly differentiated histologic type carcinomas became more common in France and in low-risk areas, but is it a relative or an absolute increase? There has been also an unexplained change in location of the tumor with a decreasing incidence in the cancers occurring in the prepyloric area and an increasing incidence in those occurring in the gastric cardia area. Early gastric carcinoma should be really a precursor of the invasive gastric carcinomas. Diagnosis of gastric carcinoma is now based on gastroscopy and biopsy of the lesion. Tumoral extension through the gastric wall and nodal involvement can be appreciated by endoscopic sonography. The procedure (subtotal versus total gastrectomy) depends on the site and extent of the lesion. Elective total gastrectomy is not advocated in patients with carcinoma of the antrum. The value of extended lymph node dissection commonly performed in Japan, is still controversial in Western countries. In patients with carcinoma of the gastric cardia, there is controversy concerning the approach and type of resection, in relation with the frequent esophageal and mediastinal extension of the tumor. In a global series including 408 operated patients, the 5-year survival rate was 51% after resection with curative intent and the overall 5-year survival was 28%.(ABSTRACT TRUNCATED AT 250 WORDS)

Limy bile. A surgical experience in 16 patients.

OBJECTIVES: This study is a retrospective analysis of clinical symptoms and operative findings in 16 patients with limy bile (mean age: 47.3 years, M/F ratio: 1/7) operated on over a 25-year period. METHODS: The patients were separated into two groups: patients with limy bile limited to the gallbladder and those with limy bile extending to the common bile duct. RESULTS: In the group of patients with limy bile in the gallbladder (n = 11), previous attacks of biliary pain were present in 9 and the gallbladder was entirely inactive in 9; an elective cholecystectomy was performed; an impacted stone was found in the neck of the gallbladder (n = 5) or in the cystic duct (n = 6), and the intraoperative cholangiogram was normal. The material deposited in the gallbladder was characteristically creamy or dense, white or yellow-brown, and consisted of calcium carbonate. The patients with limy bile extending to the common duct (n = 5) were admitted with acute pain and jaundice, and operated on a few days later. In the common bile duct, limy bile was associated with small stones (n = 4). CONCLUSION: Abdominal radiographs are sufficient to identify limy bile. The presence of this condition in the gallbladder is always associated with biliary lithiasis and the obstruction of the cystic duct. The presence of limy bile in the common bile duct is due to the migration of impacted stone and calcareous material deposited in from the gallbladder. Surgical treatment is only necessary in patients with specific biliary symptoms.