Reovirus exerts potent oncolytic effects in head and neck cancer cell lines that are independent of signalling in the EGFR pathway

Background: reovirus exploits aberrant signalling downstream of Ras to mediate tumor-specific oncolysis. Since ~90% squamous cell carcinomas of the head and neck (SCCHN) over-express EGFR and SCCHN cell lines are sensitive to oncolytic reovirus, we conducted a detailed analysis of the effects of reovirus in 15 head and neck cancer cell lines. Both pre- and post-entry events were studied in an attempt to define biomarkers predictive of sensitivity/resistance to reovirus. In particular, we analysed the role of EGFR/Ras signalling in determining virus-mediated cytotoxicity in SCCHN. Methods: to test whether EGFR pathway activity was predictive of increased sensitivity to reovirus, correlative analyses between reoviral IC50 by MTT assay and EGFR levels by western blot and FACS were conducted. Inhibition or stimulation of EGFR signalling were analysed for their effect on reoviral oncolysis by MTT assay, and viral growth by TCID50 assay. We next analysed the effects of inhibiting signalling downstream of Ras, by specific inhibitors of p38MAPK, PI3-K or MEK, on reoviral killing examined by MTT assay. The role of PKR in reoviral killing was also determined by blockade of PKR using 2-aminopurine and assaying for cell survival by MTT assay. The apoptotic response of SCCHN to reovirus was examined by western blot analysis of caspase 3 cleavage. Results: correlative analyses between reoviral sensitivity and EGFR levels revealed no association. Intermediate sub-viral and core particles showed the same infectivity/cytotoxicity as intact reovirus. Therefore, sensitivity was not determined by cell entry. In 4 cell lines, oncolysis and viral growth were both unaffected by inhibition or stimulation of EGFR signalling. Inhibition of signalling downstream of Ras did not abrogate reoviral oncolysis and, in addition, modulation of PKR using 2-aminopurine did not alter reovirus sensitivity in resistant cell lines. Caspase 3 cleavage was not detected in infected cells and oncolysis was observed in pan-caspase inhibited cells. Conclusions: in summary, reovirus is potently oncolytic in a broad panel of SCCHN cell lines. Attempts to define sensitivity/resistance by analysis of the EGFR/Ras/MAPK pathway have failed to provide a clear predictive biomarker of response. Further analysis of material from in vitro and clinical studies is ongoing in an attempt to shed further light on this issue

Différence par corps : les chirurgiennes

Joan Cassell : Difference by the body : Women surgeons As a medical speciality, surgery is uniquely physical, distinctively embodied. It involves bodies, surgeons ‘as well as patients’. During an operation the surgeon pierces the patient’s envelope of skin, violating bodily integrity. What does it mean when the surgeon is a woman ? Does the woman in the body relate to the bodies of patients the same way as a man ? Does her body have the same meaning to patients, colleagues, superiors, and subordinates ? A central issue in the study of gender is whether women and men are fundamentally different or essentially the same. How can we understand the differences and similarities in surgeiy — and elsewhere ?En tant que spécialité médicale, la chirurgie est une activité physique, incorporée d’une manière unique. Elle concerne les corps, celui du chirurgien comme celui du patient. Pendant l’intervention, le chirurgien perce l’enveloppe corporelle du patient, violant son intégrité. Quelle signification donner au fait que le chirurgien est une chirurgienne ? Le « corps à corps » patient/chirurgien est-il transformé par un corps de femme ? Ce corps a-t-il la même signification pour ses patients, ses collègues, ses supérieurs, ses subordonnés ? La question centrale dans les études sur le genre est de savoir si les hommes et les femmes sont fondamentalement différents ou essentiellement les mêmes. Comment comprendre différences et ressemblances en chirurgie - comme ailleurs ?Cassell Joan, Le Doaré Hélène. Différence par corps : les chirurgiennes. In: Cahiers du Genre, N°29, 2000. Variations sur le corps. pp. 53-81

Différence par corps : les chirurgiennes

Joan Cassell : Difference by the body : Women surgeons As a medical speciality, surgery is uniquely physical, distinctively embodied. It involves bodies, surgeons ‘as well as patients’. During an operation the surgeon pierces the patient’s envelope of skin, violating bodily integrity. What does it mean when the surgeon is a woman ? Does the woman in the body relate to the bodies of patients the same way as a man ? Does her body have the same meaning to patients, colleagues, superiors, and subordinates ? A central issue in the study of gender is whether women and men are fundamentally different or essentially the same. How can we understand the differences and similarities in surgeiy — and elsewhere ?En tant que spécialité médicale, la chirurgie est une activité physique, incorporée d’une manière unique. Elle concerne les corps, celui du chirurgien comme celui du patient. Pendant l’intervention, le chirurgien perce l’enveloppe corporelle du patient, violant son intégrité. Quelle signification donner au fait que le chirurgien est une chirurgienne ? Le « corps à corps » patient/chirurgien est-il transformé par un corps de femme ? Ce corps a-t-il la même signification pour ses patients, ses collègues, ses supérieurs, ses subordonnés ? La question centrale dans les études sur le genre est de savoir si les hommes et les femmes sont fondamentalement différents ou essentiellement les mêmes. Comment comprendre différences et ressemblances en chirurgie - comme ailleurs ?Cassell Joan, Le Doaré Hélène. Différence par corps : les chirurgiennes. In: Cahiers du Genre, N°29, 2000. Variations sur le corps. pp. 53-81