EGFR Soluble Isoforms and Their Transcripts Are Expressed in Meningiomas

The EGFR (epidermal growth factor receptor) is involved in the oncogenesis of many tumors. In addition to the full-length EGFR (isoform a), normal and tumor cells produce soluble EGFR isoforms (sEGFR) that lack the intracellular domain. sEGFR isoforms b, c and d are encoded by EGFR variants 2 (v2), 3 (v3) and 4 (v4) mRNA resulting from gene alternative splicing. Accordingly, the results of EGFR protein expression analysis depend on the domain targeted by the antibodies. In meningiomas, EGFR expression investigations mainly focused on EGFR isoform a. sEGFR and EGFRvIII mutant, that encodes a constitutively active truncated receptor, have not been studied. In a 69 meningiomas series, protein expression was analyzed by immunohistochemistry using extracellular domain targeted antibody (ECD-Ab) and intracellular domain targeted antibody (ICD-Ab). EGFRv1 to v4 and EGFRvIII mRNAs were quantified by RT-PCR and EGFR amplification revealed by MLPA. Results were analyzed with respect to clinical data, tumor resection (Simpson grade), histological type, tumor grade, and patient outcome.Immunochemical staining was stronger with ECD-Ab than with ICD-Ab. Meningiomas expressed EGFRv1 to -v4 mRNAs but not EGFRvIII mutant. Intermediate or high ECD-Ab staining and high EGFRv1 to v4 mRNA levels were associated to a better progression free survival (PFS). PFS was also improved in women, when tumor resection was evaluated as Simpson 1 or 2, in grade I vs. grade II and III meningiomas and when Ki67 labeling index was lower than 10%.Our results suggest that, EGFR protein isoforms without ICD and their corresponding mRNA variants are expressed in meningiomas in addition to the whole isoform a. EGFRvIII was not expressed. High expression levels seem to be related to a better prognosis. These results indicate that the oncogenetic mechanisms involving the EGFR pathway in meningiomas could be different from other tumor types

Toward a doxorubicin-loaded bioinspired bone cement for the localized treatment of osteosarcoma

International audienceAims: Osteosarcoma represents the second most common cause of death in children and young adults. No biomaterial allowing local drug delivery has been specifically developed. However, a biocompatible bioactive implantable material could prevent some amputations, and the local release of an antitumor agent could limit risks of relapse and metastasis. Methods: We propose a proof of concept of a self-setting paste combining amorphous calcium phosphate and doxorubicin-loaded particles of bone-like carbonated nanocrystalline apatite, as a means of local release. Results: The cement formulation and doping, first with folic acid and then with doxorubicin, was successful. Its physicochemistry was scrutinized. Preliminary in vivo data on an invasive osteosarcoma rat model suggest a limiting effect on metastatic events in the lungs without signs of toxicity

Tumour co-expression of apelin and its receptor is the basis of an autocrine loop involved in the growth of colon adenocarcinomas

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Potential side effect of propofol and sevoflurane for anesthesia of anti-NMDA-R encephalitis.

International audienceBACKGROUND: Many anesthetic drugs interact with the NMDA receptor and may therefore alter the clinical presentation of anti-NMDA-R encephalitis. CASE PRESENTATION: A 24-year-old woman was admitted to hospital for decreased consciousness and hyperthermia. Cerebrospinal fluid analysis revealed lymphocytic pleocytosis, and elevated protein. Cultures were negative. Patient state worsened with agitation, facial dyskinesia, ocular deviation, and limb dystonia. Diagnosis of anti-NMDA-R encephalitis was evidenced by specific antibodies. High doses of methylprednisolone were administered. CT scan disclosed an ovarian teratoma and tumor resection was scheduled under anesthesia with propofol, sufentanil, atracurium and sevoflurane. Sedation after surgery was maintained with propofol. Rapidly after surgery, patient's condition deteriorated with increase of dyskinesias, and two tonic-clonic generalized seizure events. CONCLUSION: In patients with anti-NMDA-R encephalitis, anesthesia using benzodiazepines, opiates and curares, which fail to interfere with the NMDA pathway, should be preferred

Epidermal growth factor receptor expression and KRAS and BRAF mutations: study of 39 sinonasal intestinal-type adenocarcinomas.

International audienceSinonasal intestinal-type adenocarcinomas (ITACs) are uncommon tumors of poor prognosis defined by their similarities to colorectal adenocarcinomas. The involvement of the epidermal growth factor receptor (EGFR) pathway in colorectal adenocarcinoma oncogenesis is well established, and the same is expected to apply to ITACs. In a series of 39 ITACs, we investigated EGFR amplification and chromosome 7 polysomy by fluorescence in situ hybridization; EGFR, KRAS, and BRAF mutational status by polymerase chain reaction sequencing; EGFR variant messenger RNA expression by quantitative reverse transcriptase polymerase chain reaction; and EGFR protein expression by immunohistochemistry with antibodies targeting the extracellular domain, the intracellular domain, and the phosphorylated isoform. The findings were analyzed with respect to clinical data, histologic typing, and patient outcome. EGFR amplification was observed in 3 cases with a focal distribution. EGFR proteins were overexpressed in all these foci with both extracellular domain and intracellular domain antibodies, suggesting involvement of the whole receptor. Chromosome 7 polysomy was observed in 15 cases and was not associated with EGFR protein expression. EGFR, KRAS, or BRAF mutations were observed in 5 different cases. The EGFRvIII mutant was not detected. In all cases, EGFR variants were expressed. There was no association between these molecular features and patient survival. In conclusion, (1) our study revealed various EGFR expression patterns in ITACs, indicating tumor heterogeneity; (2) EGFR amplification should be distinguished from chromosome 7 polysomy; (3) fluorescence in situ hybridization analysis could be guided by immunohistochemistry; and (4) ITACs share common alterations of the EGFR pathway with colorectal adenocarcinomas, except for a lower frequency of KRAS and BRAF mutations

Expression of EGFR variant mRNA.

<p>EGFR v1, v2, v3 and v4 mRNA levels were expressed in R.A.U.</p

Relationship between immunohistochemical EGFR detection and clinicopathological parameters.

<p>Relationship between immunohistochemical EGFR detection and clinicopathological parameters.</p

Comparison for ECD-Ab and ICD-Ab score labeling.

a<p>ECD-Ab and ICD-Ab labeling was expressed as Hirsch score: strong (+++, score 301–400), intermediate (++, score 201–300), low (+, score 1–200), no expression (No, score 0).</p

Patient PFS according to clinical and biological parameters.

<p>Probability of progression free durvival (PFS) was expressed in months, according to Simpson grade (A), histological tumor grade (B), Ki67 labeling index (C), EGFRv1v2v3v4 mRNA levels (D), ECD-Ab labeling (E), and ICD-Ab labeling (F).</p