RET fusions in a small subset of advanced colorectal cancers at risk of being neglected.

Background: Recognition of rare molecular subgroups is a challenge for precision oncology and may lead to tissue-agnostic approval of targeted agents. Here we aimed to comprehensively characterize the clinical, pathological and molecular landscape of RET rearranged metastatic colorectal cancer (mCRC). Patients and methods: In this case series, we compared clinical, pathological and molecular characteristics of 24 RET rearranged mCRC patients with those of a control group of 291 patients with RET negative tumors. RET rearranged and RET negative mCRCs were retrieved by systematic literature review and by taking advantage of three screening sources: (i) Ignyta's phase 1/1b study on RXDX-105 (NCT01877811), (ii) cohorts screened at two Italian and one South Korean Institutions and (iii) Foundation Medicine Inc. database. Next-generation sequencing data were analyzed for RET rearranged cases. Results: RET fusions were more frequent in older patients (median age of 66 versus 60 years, P = 0.052), with ECOG PS 1-2 (90% versus 50%, P = 0.02), right-sided (55% versus 32%, P = 0.013), previously unresected primary tumors (58% versus 21%, P < 0.001), RAS and BRAF wild-type (100% versus 40%, P < 0.001) and MSI-high (48% versus 7%, P < 0.001). Notably, 11 (26%) out of 43 patients with right-sided, RAS and BRAF wild-type tumors harbored a RET rearrangement. At a median follow-up of 45.8 months, patients with RET fusion-positive tumors showed a significantly worse OS when compared with RET-negative ones (median OS 14.0 versus 38.0 months, HR: 4.59; 95% CI, 3.64-32.66; P < 0.001). In the multivariable model, RET rearrangements were still associated with shorter OS (HR: 2.97; 95% CI, 1.25-7.07; P = 0.014), while primary tumor location, RAS and BRAF mutations and MSI status were not. Conclusions: Though very rare, RET rearrangements define a new subtype of mCRC that shows poor prognosis with conventional treatments and is therefore worth of a specific management.

Lenalidomide normalizes tumor vessels in colorectal cancer improving chemotherapy activity.

BACKGROUND: Angiogenesis inhibition is a promising approach for treating metastatic colorectal cancer (mCRC). Recent evidences support the seemingly counterintuitive ability of certain antiangiogenic drugs to promote normalization of residual tumor vessels with important clinical implications. Lenalidomide is an oral drug with immune-modulatory and anti-angiogenic activity against selected hematologic malignancies but as yet little is known regarding its effectiveness for solid tumors. The aim of this study was to determine whether lenalidomide can normalize colorectal cancer neo-vessels in vivo, thus reducing tumor hypoxia and improving the benefit of chemotherapy. METHODS: We set up a tumorgraft model with NOD/SCID mice implanted with a patient-derived colorectal cancer liver metastasis. The mice were treated with oral lenalidomide (50 mg/Kg/day for 28 days), intraperitoneal 5-fluorouracil (5FU) (20 mg/Kg twice weekly for 3 weeks), combination (combo) of lenalidomide and 5FU or irrelevant vehicle. We assessed tumor vessel density (CD146), pericyte coverage (NG2; alphaSMA), in vivo perfusion capability of residual vessels (lectin distribution essay), hypoxic areas (HP2-100 Hypoxyprobe) and antitumor activity in vivo and in vitro. RESULTS: Treatment with lenalidomide reduced tumor vessel density (p = 0.0001) and enhanced mature pericyte coverage of residual vessels (p = 0.002). Perfusion capability of tumor vessels was enhanced in mice treated with lenalidomide compared to controls (p = 0.004). Accordingly, lenalidomide reduced hypoxic tumor areas (p = 0.002) and enhanced the antitumor activity of 5FU in vivo. The combo treatment delayed tumor growth (p = 0.01) and significantly reduced the Ki67 index (p = 0.0002). Lenalidomide alone did not demonstrate antitumor activity compared to untreated controls in vivo or against 4 different mCRC cell lines in vitro. CONCLUSIONS: We provide the first evidence of tumor vessel normalization and hypoxia reduction induced by lenalidomide in mCRC in vivo. This effect, seemingly counterintuitive for an antiangiogenic compound, translates into indirect antitumor activity thus enhancing the therapeutic index of chemotherapy. Our findings suggest that further research should be carried out on synergism between lenalidomide and conventional therapies for treating solid tumors that might benefit from tumor vasculature normalization.

[Deep pudendal reflex]. / Reflejo pudendo profundo.

32 healthy women ranging from 20 to 68 years (51.84 +/- 10.36) were tested for Deep Pudendal Reflex (DPR). Dantec 13L40 (St. Mark's) superficial electrodes were used to pick up the responses of the external anal sphincter. These devices consist of a bipolar stimulating electrode mounted on the tip of the gloved index finger which is inserted into the rectum; 3 cm proximally at the base of the finger are recording electrodes which pick up the contraction response of the anal sphincter. To obtain the DPR the ischial spine is localized on transrectal examination and electrical stimuli given at that side, applying square stimulus of 0.2 ms duration and 0.5 Hz frequency. This stimulates the pudendal nerve as it leaves the pelvis through the greater sciatic notch, before it branches into the inferior rectal (to the anal sphincter) and perineal nerve (to the periurethral striated muscle). The conduction time was measured as the latency from the time of stimulation of the starting point of the reflex response curves. The shortest latency of various responses was accepted and measured in milliseconds (ms). The amplitudes of the responses were measured in microvolts (uv). We obtained reproducible DPR in all subjects. Mean latency was 36.18 +/- 4.29 ms; mean amplitude was 337.50 +/- 218.49 uv (Fig. 1, Table 2). DPR is a pudendal-anal reflex like the bulbo-cavernous reflex, but differs in latency, stimulation localization and afferent limb although both follow a common final afferent pathway.

[Usefulness of fructosamine determination in short-term monitoring of metabolic control in children with insulin-dependent diabetes mellitus at onset]. / Utilità del dosaggio delle fruttosamine nel monitoraggio a breve termine del controllo metabolico in bambini affetti da diabete mellito insulino-dipendente all'esordio.

The present study was undertaken to determine the clinical usefulness of fructosamine estimations in monitoring the short term changing in metabolic control in 5 newly diagnosed type 1 diabetic children (3 boys, 2 girls, aged 3-13 years). Mean glycaemic values, HbAlc (normal range: 4.77 +/- 0.67%), fructosamine (normal range: 2.65 +/- 0.65 mmol/l) were determined at the admission and after 1, 2, 3, 4 weeks. Normoglycaemia was achieved within 1 week (mean values: 232 +/- 107 mg% at admission; 98 +/- 39 mg% after 1 week of insulin therapy), HbAlc slightly decreased from 12 +/- 0.71 at admission to 9.90 +/- 1.81 after 4 weeks, but not reached normal values. Fructosamine decreased from 5.49 mmol/l to near normal values (3.02 +/- 0.67) after 4 weeks. The validity of the method was confirmed by the comparison of HbAlc and fructosamine in 22 stable long-standing diabetic children (r = 0.77, p less than 0.01). Compared with HbAlc, fructosamine appeared more useful in monitoring short term (3 weeks) changes in metabolic control. Additional advantages were lower cost and technical simplicity of measurement.

[Neonatal hypoxic-ischemic nephropathy and urinary diagnostic indices: the utility of measuring tubular enzymes (NAG and AAP)]. / Nefropatia ipossico-ischemica nel neonato ed indici diagnostici urinari: utilità del dosaggio di enzimi tubulari (NAG ed AAP).

Feto-neonatal hypoxia can cause a functional kidney impairment, which is often temporary and not clinically overt, but sometimes leading to acute renal failure. Hypoxic stress may result in a tubulo-interstitial damage, and kidney tubular enzymes determination has proved to be an easy, early, and non invasive method to define a tubular interstitial lesion. A major target of nephrotoxicity is the proximal tubular cell: alterations in brush-border membrane and cytoplasm result in increased turnover processes in the kidney cortex, following by a corresponding increased excretion of alanine-aminopeptidase (AAP) and N-acetyl-glucosaminidase (NAG) from the proximal tubular cells, long before glomerular or tubular functions are impaired. AAP and NAG excretion is directly correlated with the strength and the duration of toxic alteration of the proximal tubule. NAG and AAP have been already studied in the adults and the children; they have been chosen for this investigation with a double aim: 1) to define the amount of their urinary excretion in relation with gestational age at birth; 2) to evaluate if in the newborn, independently of the gestational age, their urinary concentration may be increased by ischaemic conditions caused by hypoxia. We studied 52 healthy newborns (7 preterm of 33-36 weeks and 45 full-term) and 16 newborns with feto-neonatal hypoxia (8 preterm of 26-36 weeks and full-term) at the forth day of life. Urinary NAG and AAP were assayed by colorimetric methods and the results expressed as mU/mg. creatininuria.(ABSTRACT TRUNCATED AT 250 WORDS)

Met signaling regulates growth, repopulating potential and basal cell-fate commitment of mammary luminal progenitors: implications for basal-like breast cancer.

Basal-like breast cancer is an aggressive subtype of mammary carcinoma. Despite expressing basal markers, typical of mammary stem cells, this tumor has been proposed to originate from luminal progenitors, which are downstream of stem cells along the mammary epithelial hierarchy. This suggests that committed luminal progenitors may reacquire basal, stem-like characteristics, but the mechanisms that regulate this transition remain unclear. Using mouse models, we found that luminal progenitors express high levels of the Met receptor for hepatocyte growth factor (HGF), as compared with the other mammary epithelial sub-populations. Constitutive activation of Met led luminal progenitors to attain stem cell properties, including enhanced clonogenic activity in vitro and de novo ability to reconstitute mammary glands in repopulation assays in vivo. Moreover, in response to Met signaling, luminal progenitors gave rise to hyperplastic ductal morphogenesis and preferentially underwent basal lineage commitment at the expense of luminal cell-fate specification. Opposite and symmetric results were produced by systemic pharmacological inhibition of Met. Hence, Met signaling targets luminal progenitors for expansion, impairs their differentiation toward the mature luminal phenotype and enables their commitment toward the basal lineage. These results emphasize a critical role for Met in promoting deregulated proliferation and basal plasticity of normal luminal progenitors in the mammary gland, a complex of events that may be required for sustaining the functional and phenotypic properties of basal-like breast tumors.

Met-driven invasive growth involves transcriptional regulation of Arhgap12.

Invasive growth is a complex biological program triggered by hepatocyte growth factor (HGF) through its tyrosine kinase receptor encoded by the Met proto-oncogene. The program involves-besides proliferation-cell dissociation, motility and invasiveness, controlled by intracellular signals impinging on PI3K and on the small G-proteins of the Rac/Rho family. The mechanism(s) unbalancing Rac/Rho activation are still not completely clarified. Here, we describe a functional link between HGF and Arhgap12, a gene encoding a previously uncharacterized protein of the RhoGAP family. We identified Arhgap12 as a transcriptional target of HGF, through a novel gene trapping strategy. We found that Arhgap12 mRNA and protein are robustly suppressed by HGF treatment, but not by serum. Arhgap12 displayed GTPase activating protein (GAP) activity towards Rac1 and, upon overexpression, impaired cell scattering, invasion and adhesion to fibronectin in response to HGF. Consistently, Arhgap12 silencing by RNA interference selectively increased the scatter and adhesion responses. These data show that HGF-driven invasive growth involves transcriptional regulation of a Rac1-specific GAP.

A signaling adapter function for alpha6beta4 integrin in the control of HGF-dependent invasive growth.

alpha6beta4 integrin and the Met receptor for HGF have been shown independently to promote invasive growth. We demonstrate here that Met selectively associates with alpha6beta4. In carcinoma cells expressing Met alone, HGF does not exert significant biological effects. Ectopic expression of alpha6beta4 restores HGF-regulated processes. Following Met activation, alpha6beta4 is tyrosine phosphorylated and combines with Shc and PI3K, generating an additional signaling platform that potentiates HGF-triggered activation of Ras- and PI3K-dependent pathways. In the presence of an alpha6beta4 mutant defective for Shc recruitment, Met cannot sustain HGF-mediated responses. Surprisingly, a truncated beta4 unable to bind laminins retains the activity of wild-type alpha6beta4. Such findings invoke an unexpected role for alpha6beta4 in cancer invasion as a functional amplifier of biochemical outputs rather than a mechanical adhesive device.

Pudendal reflexes in women with pelvic floor disorders.

The objective of this work was to study two pudendal anal reflexes: Deep Pudendal Reflex (DPR) and classical Bulbocavernosus Reflex (BCR) in women with primary and recurrent genital prolapse to obtain support to the hypothesis of pelvic nerve damage in patients with pelvic floor disorders. 124 women were studied: 68 were normal; 38 with genital prolapse (GP); and 18 with recurrent GP. Clinical and electrophysiological studies were carried out. Delayed reflex responses were found in 44/56 of patients (79%). [27/38 in genital prolapse group (71%); 17/18 in recurrent GP group (94%)]. The evaluation of pelvic floor reflex responses are tests to be taken into account in the diagnosis and management of pelvic floor disorders.

Renal tubular dysfunction in chronic alcohol abuse--effects of abstinence.

BACKGROUND: Alcohol abuse may be accompanied by a variety of disorders of electrolyte and acid-base metabolism. The role of the kidney in the pathogenesis of these disturbances is obscure. We sought to evaluate the alcohol-induced abnormalities of renal function and improvement during abstinence and to assess the relation between renal dysfunction and electrolyte and acid-base disorders. METHODS: We measured biochemical constituents of blood and renal function before and after four weeks of abstinence in 61 patients with chronic alcoholism who had little or no liver disease. RESULTS: On admission, 18 patients (30 percent) had hypophosphatemia and hypomagnesemia, 13 patients (21 percent) had hypocalcemia, and 8 patients (13 percent) had hypokalemia. Twenty-two patients (36 percent) had a variety of simple and mixed acid-base disorders. Twenty of these patients had metabolic acidosis, and among them, 80 percent had alcoholic acidosis. A wide range of defects in renal tubular function, with normal glomerular filtration rate, were detected in these patients. The defects included decreases in the threshold and maximal reabsorptive ability for glucose (38 percent of patients) and in the renal threshold for phosphate excretion (36 percent); increases in the fractional excretion of beta 2-microglobulin (38 percent), uric acid (12 percent), calcium (23 percent), and magnesium (21 percent); and aminoaciduria (38 percent). Seventeen patients (28 percent) had a defect in tubular acidification, and five an impairment in urinary concentrating ability. Urinary excretion of N-acetyl-beta-D-glucosaminidase and alanine aminopeptidase were increased in 41 and 34 percent of patients, respectively. The abnormalities of blood chemistry and renal tubular function disappeared after four weeks of abstinence. CONCLUSIONS: Transient defects in renal tubular function are common in patients with chronic alcoholism and may contribute to their abnormalities of serum electrolyte and blood acid-base profiles.

HGF/scatter factor selectively promotes cell invasion by increasing integrin avidity.

Hepatocyte growth factor/scatter factor (HGF/SF) controls a genetic program known as 'invasive growth', which involves as critical steps cell adhesion, migration, and trespassing of basement membranes. We show here that in MDA-MB-231 carcinoma cells, these steps are elicited by HGF/SF but not by epidermal growth factor (EGF). Neither factor substantially alters the production or activity of extracellular matrix proteases. HGF/SF, but not EGF, selectively promotes cell adhesion on laminins 1 and 5, fibronectin, and vitronectin through a PI3-K-dependent mechanism. Increased adhesion is followed by enhanced invasiveness through isolated matrix proteins as well as through reconstituted basement membranes. Inhibition assays using function-blocking antibodies show that this phenomenon is mediated by multiple integrins including beta1, beta3, beta4, and beta5. HGF/SF triggers clustering of all these integrins at actin-rich adhesive sites and lamellipodia but does not quantitatively modify their membrane expression. These data suggest that HGF/SF promotes cell adhesion and invasiveness by increasing the avidity of integrins for their specific ligands.

Disfunción urinaria en el síndrome de Isaacs / Urinary dysfunctiion of acquired neuromyotonia (Isaacs'Syndrome)

La neuromiotonía es una afección que se presenta con endurecimiento muscular difuso, espasmos y/o acalmbres, usualmente asociados a hiperhidrosis, que pueden observarse en forma idiopática o secundaria. En 1961, Isaacs describió el síndrome en forma completa demostrando su origen en los nervios periféricos. Puede corresponder a patología hereditaria o adquirida, asociándopse a cuadros pareneoplásicos o autoinmunes, con o sin neuropatía periférica. Existe una sola coimunicación en la literatura de Síndrome de Isaacs con disfunción urinaria. Nosotros presentamos la primera descripción urodinámica realizada a una paciente con dicha entidad comprobando la presencia de una hiperreflexia rectal y del detrusor, hallazgos generalmente asociados a lesiones del SNC

Síndrome Post-polio / Clinical features and electromyographic variables in patients with post-polio syndrome

La primera descripción del síndrome de post-polio fue publicada en la literatura francesa en 1875, pero se reconoce recién esta entidad a partir de la dúcada de los 80. Su inicio es aproximadamente 30 años después del episodio agudo a través de distintos síntomas: fatiga, debilidad de músculos previamente afectados y previamente no afectados, dolor, intolerancia al frío, atrofia muscular y nuevos problemas de la vida diaria. Se estudiaron 12 pacientes que presentaron nueva sintomatología, principalmente debilidad muscular y dolor en distintos grupos musculares, ya sea por desuso o por un esfuerzo exagerado y dolor en las articulaciones