Earlier studies of invasive breast tumors have shown that 60 -80% are aneuploid and Ϸ80% exhibit amplified centrosomes. In this study, we investigated the relationship of centrosome amplification with aneuploidy, chromosomal instability, p53 mutation, and loss of differentiation in human breast tumors. Twenty invasive breast tumors and seven normal breast tissues were analyzed by fluorescence in situ hybridization with centromeric probes to chromosomes 3, 7, and 17. We analyzed these tumors for both aneuploidy and unstable karyotypes as determined by chromosomal instability. The results were then tested for correlation with three measures of centrosome amplification: centrosome size, centrosome number, and centrosome microtubule nucleation capacity. Centrosome size and centrosome number both showed a positive, significant, linear correlation with aneuploidy and chromosomal instability. Microtubule nucleation capacity showed no such correlation, but did correlate significantly with loss of tissue differentiation. Centrosome amplification was detected in in situ ductal carcinomas, suggesting that centrosome amplification is an early event in these lesions. Centrosome amplification and chromosomal instability occurred independently of p53 mutation, whereas p53 mutation was associated with a significant increase in centrosome microtubule nucleation capacity. Together, these results demonstrate that independent aspects of centrosome amplification correlate with chromosomal instability and loss of tissue differentiation and may be involved in tumor development and progression. These results further suggest that aspects of centrosome amplification may have clinical diagnostic and͞or prognostic value and that the centrosome may be a potential target for cancer therapy.

Our data support the notion that human follicle development can be achieved in vitro in a bio-engineered culture system. More studies are required to investigate whether the fully sized oocytes obtained from in vitro grown follicle are competent to resume meiosis and be fertilized.

This encapsulated 3D culture model permits further studies on the endocrine and local factors that influence primate follicle growth and oocyte maturation, with relevance to enhancing fertility preservation options in women.

Molecular mechanisms leading to genomic instability and phenotypic variation during tumor development and progression are poorly understood. Such instability represents a major problem in the management of breast cancer because of its contribution to more aggressive phenotypes as well as chemoresistance. In this study we analyzed breast carcinomas and tumor-derived cell lines to determine the relationship between centrosome amplification and established prognostic factors. Our results show that centrosome amplification can arise independent of ER or p53 status and is a common feature of aneuploid breast tumors. Centrosome amplification is associated with mitotic spindle abnormalities in breast carcinomas and thus may contribute to genomic instability and the development of more aggressive phenotypes during tumor progression.

Female cancer patients who seek fertility preservation but cannot undergo ovarian stimulation and embryo preservation may consider 1) retrieval of immature oocytes followed by in vitro maturation (IVM) or 2) ovarian tissue cryopreservation followed by transplantation or in vitro follicle culture. Conventional IVM is carried out during the follicular phase of menstrual cycle. There is limited evidence demonstrating that immature oocyte retrieved during the luteal phase can mature in vitro and be fertilized to produce viable embryos. While in vitro follicle culture is successful in rodents, its application in nonhuman primates has made limited progress. The objective of this study was to investigate the competence of immature luteal-phase oocytes from baboon and to determine the effect of folliclestimulating hormone (FSH) on baboon preantral follicle culture and oocyte maturation in vitro. Oocytes from small antral follicle cumulus-oocyte complexes (COCs) with multiple cumulus layers (42%) were more likely to resume meiosis and progress to metaphase II (MII) than oocytes with a single layer of cumulus cells or less (23% vs. 3%, respectively). Twenty-four percent of mature oocytes were successfully fertilized by intracytoplasmic sperm injection, and 25% of these developed to morula-stage embryos. Preantral follicles were encapsulated in fibrin-alginate-matrigel matrices and cultured to small antral stage in an FSH-independent manner. FSH negatively impacted follicle health by disrupting the integrity of oocyte and cumulus cells contact. Follicles grown in the absence of FSH produced MII oocytes with normal spindle structure. In conclusion, baboon luteal-phase COCs and oocytes from cultured preantral follicles can be matured in vitro. Oocyte meiotic competence correlated positively with the number of cumulus cell layers.This study clarifies the parameters of the follicle culture system in nonhuman primates and provides foundational data for future clinical development as a fertility preservation option for women with cancer.

The centrosome functions as the major microtubule organizing center (MTOC) of the cell and as such it determines the number, polarity, and organization of interphase and mitotic microtubules. Cytoplasmic organization, cell polarity and the equal partition of chromosomes into daughter cells at the time of cell division are all dependent on the normal function of the centrosome and on its orderly duplication, once and only once, in each cell cycle. Malignant tumor cells show characteristic defects in cell and tissue architecture and in chromosome number that can be attributed to inappropriate centrosome behavior during tumor progression. In this review, we will summarize recent observations linking centrosome defects to disruption of normal cell and tissue organization and to chromosomal instability found in malignant tumors.

Purpose To investigate the role of cumulus cell contact during oocyte maturation on meiotic spindle assembly and the acquisition of developmental competence. Methods Cumulus oocyte complexes isolated from mouse ovaries subjected to in vitro or in vivo maturation were analyzed by confocal microscopy with respect to oocyte somatic cell contacts and for their ability to develop after parthenogenic activation during embryo culture. Results Cell contact is maintained during maturation in vivo, predisposing oocytes to cortical meiotic spindle assembly and developmental competence acquisition. In contrast, oocytes matured in vitro lose cell contact coincident with central meiotic spindle assembly that results in cleavage delays upon egg activation and failure to form blastocysts. Experimental disruption of cell contact by the actin-depolymerizing agent latrunculin B results in the formation of enlarged meiotic spindles with dispersed chromosomes unlike the compact ordering of chromosomes observed on spindles formed after in vivo maturation, suggesting a link between cell contact and the acquisition of developmental competence. Conclusions Somatic cell contact optimizes oocyte quality during meiotic maturation by regulating the spatial organization and function of the meiotic spindle through actindependent mechanisms that enhance development.

Ovarian vein blood was collected by cannulating the ovarian vein of 37 ewes at various times during the oestrous cycle. Plasma progesterone and oestrogen concentrations, determined by chemical methods, showed marked cyclic variations during the cycle. Progesterone was detected at all stages of the cycle. Plasma concentrations were rising rapidly by the 4th day after the onset of oestrus and were maintained at levels greater than 100 \g=m\g./100 ml. plasma from the 8th to the 14th day of the cycle. They started to fall about 48 hr. before the onset of oestrus. Very low levels, of the order of 1 \g=m\g./100 ml. plasma, were maintained from 24 hr. before to 8\p=n-\16 hr. after the onset of oestrus.Oestradiol-17\g=b\ made up almost all of the oestrogens measured. Oestrone accounted for less than one-eighth of the total oestrogens. Oestradiol first appeared on the 14th day of the cycle and its concentration rose rapidly during the immediate pre-oestrous period to reach peak levels of over 100 ng./100 ml. plasma 20\p=n-\30 hr. before the onset of oestrus. They then rapidly declined and by 24 hr. after the onset had reached almost non\x=req-\ detectable levels.The ovarian secretion rate of progesterone was calculated to be 3\ m=. \ 5mg./ day at mid-cycle and the total secretion of oestradiol during the follicular phase was 4\m=.\9 \g=m\g. Blood flow through the cannula was not affected by either the stage of cycle at which blood was collected or by the structure (corpus luteum or Graafian follicle) in the ovary bled.