P-437 Follicle activation in human ovarian tissue: impact of freezing, culture and grafting

Study question

How does freezing, in vitro culture (IVC) and grafting to chorioallantoic membrane (CAM) affect follicle activation through the PI3K pathway in human ovarian tissue?

Summary answer

Freezing does not trigger further follicle activation. Although IVC and CAM do induce follicle activation, the process is significantly curbed in the CAM group.

What is known already

While massive follicle activation has been shown to occur through the PI3K pathway in frozen-thawed human ovarian tissue after both short-term xenotransplantation and IVC, it remains poorly understood in fresh ovarian tissue, raising many questions about the effect of freezing on follicle activation. Furthermore, grafting ovarian tissue to CAM has been found to limit follicle activation in animal ovarian tissue, though its impact on human follicles is yet to be elucidated.

Study design, size, duration

Thirty fresh cortical fragments from 5 patients and 50 frozen-thawed tissue pieces from another 5 patients were investigated. We first compared fresh fragments (fresh-IVC) with frozen-thawed tissue (FT-IVC) by IVC. These cultured frozen-thawed fragments were then examined against frozen-thawed fragments grafted to CAM (FT-CAM). After both IVC and CAM grafting, ovarian cortical pieces (4x2x1 mm) were analyzed on day (D) 0, 1 and 6.

Participants/materials, setting, methods

Follicle analyses included histology (count and classification), transmission electron microscopy (ultrastructure), immunohistochemistry (Ki67 for follicle proliferation, c-caspase-3 for follicle apoptosis, LC3B for follicle autophagy, p-AKT for PI3K activation and p-rpS6 for PI3K/mTOR activation), and immunofluorescence (FOXO1 for PI3K/FOXO activation). Subcellular localization of FOXO1 was determined in primordial follicles on high-resolution images using structured illumination microscopy. Droplet digital PCR further investigated expression of PI3K pathway-related genes (TSC1 and CDKN1B) and oocyte growth-related genes (GDF9 and LHX8).

Main results and the role of chance

No differences were detected between the fresh-IVC and the FT-IVC groups in any conducted analyses. After both IVC and CAM grafting, a significant decrease was observed in primordial follicle proportions in all groups on D6 vs D0 (p < 0.01), associated with a substantial increase in intermediate follicle proportions (p < 0.05). In the FT-CAM group, however, the percentage of primordial follicles stabilized between D1 and D6, showing significantly higher rates than the FT-IVC group on D6 (p = 0.04) and reflecting better preservation of the primordial follicle pool in the FT-CAM group. While apoptotic follicle rates increased in all conditions (D0 vs D6, p < 0.03), they remained significantly lower in the FT-CAM group than in the FT-IVC group on D6 (p = 0.01), confirming superior follicle preservation in CAM-grafted tissue. In primordial follicles, significantly lower levels of p-rpS6 were noted over time in all conditions (D0 vs D6, p < 0.009), but there was a significant shift in FOXO1 to a nuclear localization in the FT-CAM group compared to the FT-IVC group on D1 (p = 0.03), indicating inhibition of follicle activation.

Limitations, reasons for caution

As demonstrated by our results, the CAM model appears to be effective at preserving the follicle pool. However, our study did not investigate the underlying mechanisms behind this improved follicle preservation after thawing.

Wider implications of the findings

Our data confirm that the freezing procedure itself does not cause follicle burnout. Moreover, the CAM model looks to be capable of preserving the follicle pool, hypothetically thanks to rapid revascularization and circulating embryonic anti-Müllerian hormone.

Trial registration number

Not applicable

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Dielectric elastomer actuators for octopus inspired suction cups

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Osmotic actuation modelling for innovative biorobotic solutions inspired by the plant kingdom

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Pattern of care and results of radiotherapy in patients 80 years old and over

BACKGROUND AND AIMS

Cancer incidence increases with age and several cancer types are observed in older patients, so the need for radiotherapy (RT) in treatment of older patients with cancer is also on the rise. This study's aims to evaluate retrospectively the pattern of care and the feasibility of RT in elderly patients (80 years old and over) treated with different intents, and the impact of RT prescription on survival.

MATERIALS AND METHODS

We reviewed 191 patient charts from the years 2005-2007, recording age, intent of treatment, site, and type of RT. Crude and actuarial survival were estimated.

RESULTS

One hundred patients were males (M) and 91 females (F); 162 were seen on an outpatient basis, 29 as inpatients. A total of 138 patients were recruited for RT; 113 were treated, 112 completed RT. The ratio to all treated patients was 113/2125 (5.3%). Overall (treated and non-treated) cumulative survival probability was 71% for the first year, 45% for the second and 27% for the third. For treated patients, the cumulative survival probability was 67% for the first year, 43% for the second year and 23% for the third year, while for untreated patients it was 76% for the first year, 47% for the second year and 32% for the third year (Log-rank test: p = 0.23).

CONCLUSIONS

RT did not decrease survival in elderly patients.

Esthesioneuroblastoma treated with external radiotherapy. Case report

Esthesioneuroblastoma is a rare tumour arising from the olfactory epithelium of the nasal vault which frequently invades the cranial base and orbit. Esthesioneuroblastoma has a bimodal age distribution between 11 and 20 years and between 51 and 60 years. Esthesioneuroblastoma accounts for approximately 1-5% of intranasal cancers. The case is reported of a 79-year-old female patient with a Kadish stage C tumour with a one-year history of headache, nasal obstruction, anosmia, rhinorrhoea and epistaxis. Aim of this study is to analyse the natural history, treatment and prognosis of this tumour, based on a review of the literature.

[Multivariate analysis of prognostic factors and survival in patients with "glioblastoma multiforme"]

PURPOSE

The aim of this study was to evaluate the survival of patients with "glioblastoma multiforme", to analyse the prognostic factors influencing the survival rate and to review recent results in the literature.

MATERIALS AND METHODS

Seventy five patients underwent radiation treatment between May 1998 and April 2003. Among the factors under investigation we ascertained that sex, chemotherapy, conformal treatment, surgery, and the choice of the irradiation area (whole brain or only the involved field) did not influence the survival in a statistically significant manner.

RESULTS

Whereas age and total dose were the 95% statistically significant variables. Hazard ratio of patients older than 58 years compared to younger patients was 1.69. The death risk was 69% in older than younger patients. A greater irradiation dose improved the survival with an increase of the median survival days. The total dose lower than 6000 cGy caused an increase of 81.8% in the death risk. The median survival from the diagnosis to the death was 14.7 months (446 days) and 1-, 2- and 3- year survival rate was 69.3%, 38.4%, and 14.7% respectively.

CONCLUSIONS

The current medical literature and our experience attests that the use of temozolomide improves the survival of these patients.