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Serge Uzan

Publications and source records attributed to Serge Uzan.

43 records · Page 3Linked to original sources
PubMed2002

Specific activation of the non-classical class I histocompatibility HLA-G antigen and expression of the ILT2 inhibitory receptor in human breast cancer.

The HLA-G molecule is a non-classical HLA class I antigen selectively expressed by trophoblastic cells that invade the maternal decidua during human pregnancy. HLA-G is believed to contribute to tolerance of the semi-allogeneic fetus by inhibiting maternal immune responses. Similarly, HLA-G expression in tumour cells may favour their escape from host immune surveillance. This study investigated HLA-G expression in human mammary tumours. Immunohistochemical analysis of cryo-preserved and paraffin-embedded breast tissue biopsies, using two HLA-G-specific antibodies, revealed that unlike non-cancerous breast tissue in the vicinity of the tumour, 14 out of 36 breast cancer lesions selectively expressed HLA-G. HLA-G expression was significantly more frequent in lesions that were highly infiltrated by host immune cells, thus correlating HLA-G activation with inflammation. Further histological and double-staining immunofluorescence analysis attributed HLA-G expression mainly to tumour epithelial cells and to subsets of infiltrating CD68+ and CD8+ cells. RT-PCR analysis suggested that HLA-G was activated at the transcriptional level in breast tumours. The presence of ILT2 (Ig-like transcript 2) killing inhibitory receptors known to interact with HLA-G was also demonstrated in host immune cells that infiltrate breast cancer lesions. These results indicate that HLA-G is up-regulated at high frequencies in human breast cancer, where it may impair efficient anti-tumour immunity.

Adult↗
PubMed2002

Down syndrome maternal serum marker screening after 18 weeks' gestation.

Women having access to prenatal care late in pregnancy may still wish to benefit from maternal serum screening for Down syndrome. Therefore, we established reference values for alpha-feto protein (AFP) and free beta-human chorionic gonadotrophin (beta-hCG), and assessed the diagnostic value of maternal serum marker screening at 18-35 weeks' gestation based upon a series of 4072 sera from unaffected pregnancies and 118 sera from pregnant women with fetuses affected by Down syndrome. Using a 1/250 risk cut-off, a detection rate of 72.9% (95% CI = 71.5-74.3%) was achieved with a false-positive rate of 7.51% (95% CI = 6.71-8.3%). This was not significantly different from the percentages observed in our 14-17 weeks routine screening (50 596 patients): 71.9% (95% CI = 71.5-72.3%) and 6.48% (95% CI = 6.28-6.68%), respectively. Detection and screen-positive rates were, respectively, 51.3% (95% CI = 35.6-67.0%) and 5.95% (95% CI = 5.12-6.68%) in women aunder 35 years of age, and 84.8% (95% CI = 76.9-92.7%) and 24% (95% CI = 20.7-27.3%) in women aged 35 years and over. In conclusion, maternal serum marker screening is feasible at 18 weeks' gestation and later, which may be of interest in selected cases.

Adult↗
PubMed2002

[Cancer and Pregnancy: the point of view of the obstetrician].

Onset of malignancy during pregnancy is distressing for the future parents and raises thorny problems for the oncologist and obstetric gynecologist. Many diagnostic and therapeutic approaches cannot be used. Some first-line reference treatments are known to cause fetal loss or severe birth defects, yet any delay in treatment may unacceptably worsen the maternal prognosis. In the absence of large randomized trials and cohort studies, it is difficult to know how best to manage these patients. An estimated one in ten thousand pregnancies are associated with malignancies, especially gynecologic tumors (cervix, breast, ovary), lymphomas, melanomas, brain tumors and leukemia. The obstetrician, in close collaboration with the oncologist, has a major role in choosing the most appropriate diagnostic and therapeutic strategy, and must keep the couple fully informed. Importantly, improvements in cancer cure rates and the development of conservative treatments mean that many of these young women can hope to start a new pregnancy after their treatment. The optimal interval between cure and conception must be carefully weighed up by a multidisciplinary team including oncologists and obstetric gynecologists. Chemotherapy, pelvic radiation therapy, and gynecologic surgery can impact not only on fertility but also on the course of a next pregnancy (increased risk of miscarriage and premature delivery, etc.). The obstetrician must take these risks into account.

Abortion, Induced↗
PubMedDate not supplied

Prenatal diagnosis of a large centromeric heteromorphism of chromosome 12: implications for genetic counseling.

Chromosomal centromeric variants can be found in the course of a prenatal diagnosis. When following the discovery of fetal abnormalities at ultrasound examination, such variants may lead to some difficulties in genetic counseling. Here we describe a new heteromorphism implicating chromosome 12, found in a fetus with a suspicion of microcephaly, and we discuss its prognostic value.

Adult↗