Xenotransplantation of human ovarian tissue to nude mice: comparison between four grafting sites

BACKGROUND

This study was designed to assess the impact of different ovarian tissue transplantation sites on the follicular pool and ovarian tissue integrity after short-term grafting, since there is no consensus in the literature as to the optimal grafting site in experimental models.

METHODS

Frozen-thawed ovarian tissue from eight patients was grafted for 1 or 3 weeks to the peritoneum, inside the ovarian bursa, under the skin and into the muscle of 16 nude mice. Assessment of follicular density and follicle classification was carried out by histological analysis. Proliferative activity was evidenced by immunostaining with anti-Ki-67 antibodies, and fibrotic areas were analyzed by morphometry on histological slides.

RESULTS

One week post-transplantation, the proportion of Ki-67-positive primordial follicles was higher (20-42%) than in controls (1.7%), demonstrating follicular activation in all four sites. Despite this activation, primordial follicles were still found 3 weeks post-grafting, (34.1-66.9% of the follicle population), most of them quiescent, as indicated by the absence of Ki-67 immunostaining. Cryopreservation and grafting resulted in extensive fibrosis in the stroma. This fibrosis was significantly less pronounced in intramuscular (IM) grafts, representing 18.8% of the surface versus 44.7-60.5% for other sites, after 3 weeks of grafting.

CONCLUSIONS

All four grafting sites equally supported early follicular growth and preserved some quiescent follicles after short-term frozen-thawed human ovarian tissue transplantation. The extensive fibrosis observed does not appear to have a major impact on early follicle development, but its long-term effects must be investigated. The graft environment may be implicated in the preservation of the stroma, as suggested by a lower degree of fibrosis in the IM site.

Fertility preservation in girls during childhood: is it feasible, efficient and safe and to whom should it be proposed?

BACKGROUND

In prepubertal and adolescent girls, fertility may be impaired by gonadotoxic treatments, repeat ovarian surgery or genetic disorders. Cryopreservation of ovarian cortex is an existing option to preserve fertility in these young girls at risk of premature ovarian failure (POF). The efficacy, feasibility and risks of ovarian cryopreservation in children must be assessed in order to validate the technique.

METHODS

Here, we conducted a review of ovarian cryopreservation in adults and, more specifically, in children using the PubMed databases. In addition, our own experience with ovarian cryopreservation in children was evaluated and compared with the literature.

RESULTS

Analysis of the literature and six published series on ovarian cryopreservation in children, as well as our own series of 58 cases, show that there is no reason to doubt its efficacy in this young population. However, no consensus has yet been reached on the indications for the technique. Indeed, with existing models, the real risk of POF may be over- or underestimated.

CONCLUSION

Our review suggests that ovarian cortex cryopreservation is feasible and as safe as comparable operative procedures in children. Although no births have yet resulted from freeze-thawing of prepubertal ovarian cortex, the results of this approach in adults are encouraging. However, the absence of consensus on the indications for fertility preservation, as well as the optimal timing and quantity of ovarian cortex for cryopreservation, should be taken into consideration when discussing fertility issues with girls at risk of POF and their parents.

Involvement of the nuclear factor-κB pathway in the pathogenesis of endometriosis

OBJECTIVE

To evaluate the role of nuclear factor-κB (NF-κB) in the pathogenesis of endometriosis.

DESIGN

A literature search was conducted in PubMed to identify all relevant citations.

RESULT(S)

Our findings highlight the important role of NF-κB in the pathophysiology of endometriosis. In vitro and in vivo studies show that NF-κB-mediated gene transcription promotes inflammation, invasion, angiogenesis, and cell proliferation and inhibits apoptosis of endometriotic cells. Constitutive activation of NF-κB has been demonstrated in endometriotic lesions and peritoneal macrophages of endometriosis patients. Agents blocking NF-κB are effective inhibitors of endometriosis development and some drugs with known NF-κB inhibitory properties have proved efficient at reducing endometriosis-associated symptoms in women. Iron overload activates NF-κB in macrophages. NF-κB activation in macrophages and ectopic endometrial cells stimulates synthesis of proinflammatory cytokines, generating a positive feedback loop in the NF-κB pathway and promoting endometriotic lesion establishment, maintenance and development.

CONCLUSION(S)

NF-κB transcriptional activity modulates key cell processes contributing to the initiation and progression of endometriosis. Because endometriosis is a multifactorial disease, inhibiting NF-κB appears to be a promising strategy for future therapies targeting different cell functions involved in endometriosis development, such as cell adhesion, invasion, angiogenesis, inflammation, proliferation, and apoptosis. Upcoming research will elucidate these hypotheses.

Differential expression of genes from the homeobox A cluster in deep endometriotic nodules and peritoneal lesions

OBJECTIVE

To compare expression of homeobox A (HOXA) genes involved in the differentiation of the female reproductive tract in deep endometriotic nodules and peritoneal lesions.

DESIGN

Prospective experimental study.

SETTING

Academic gynecology research unit.

PATIENT(S)

Thirty patients undergoing laparoscopy.

INTERVENTION(S)

During laparoscopy, deep endometriotic nodules (n=30) and peritoneal lesions (n=11) were recovered. Eutopic endometrium and vaginal tissue (n=30) were collected for control purposes.

MAIN OUTCOME MEASURE(S)

Quantification of HOXA-9, HOXA-10, HOXA-11, and HOXA-13 in deep nodules, peritoneal lesions, and control samples by real-time reverse-transcription polymerase chain reaction, and localization of HOXA-10 and HOXA-13 proteins by immunohistochemistry.

RESULT(S)

The HOXA-13 transcripts were detected in 29 out of 30 nodules, and their expression was significantly higher than in vaginal tissue, but they were barely detectable in endometrium and peritoneal lesions. Expression of HOXA-10 and HOXA-11 transcripts in deep nodules was similar to eutopic endometrium, and HOXA-10 expression was significantly lower in peritoneal endometriotic lesions. The HOXA-10 immunostaining was mainly localized in the stroma of deep endometriotic nodules, HOXA-13 in glandular structures and stroma, and neither of these proteins were detected in fibromuscular areas.

CONCLUSION(S)

Marked expression of HOXA-10 and HOXA-13 in the endometrium-like tissue of nodules but low expression in peritoneal endometriotic lesions supports the theory of differential origin of these two types of endometriosis.

Expression of eicosanoid biosynthetic and catabolic enzymes in peritoneal endometriosis

BACKGROUND

Increased peritoneal eicosanoid concentrations have been reported in endometriosis patients and might be important in disease-associated pain and inflammation. Here, we evaluated the expression of key biosynthetic and catabolic enzymes involved in this abnormal eicosanoid production in peritoneal macrophages and endometriotic lesions.

METHODS

Peritoneal macrophages, endometriotic lesions and matched eutopic endometrium were collected from endometriosis patients (n = 40). Peritoneal macrophages and eutopic endometrium samples were also collected from disease-free women (n = 25). Expression of type IIA secretory phospholipase A(2) (sPLA(2)-IIA), cyclooxygenase-2 (COX-2), microsomal prostaglandin E synthase-1 (mPGES-1), 15-hydroxyprostaglandin dehydrogenase (15-PGDH) and 5-lipoxygenase (5-LO) was quantified by real-time PCR, and these five key enzymes were localized by immunohistochemistry.

RESULTS

sPLA(2)-IIA, COX-2 and mPGES-1 mRNA was significantly increased in peritoneal macrophages of endometriosis patients compared with controls (P = 0.006, P = 0.016 and P = 0.025, respectively). In endometriosis patients, sPLA(2)-IIA, mPGES-1 and 15-PGDH mRNA was significantly enhanced in peritoneal lesions compared with matched eutopic endometrium (P < 0.001, P < 0.001 and P = 0.005, respectively). In eutopic endometrium, a significant decrease in 15-PGDH mRNA was found in the endometriosis group compared with controls (P = 0.023). Finally, sPLA(2)-IIA, COX-2, mPGES-1 and 15-PGDH immunostaining was found mainly in endometrial glands, whereas 5-LO was distributed throughout the glands and stroma.

CONCLUSIONS

Our study highlights an imbalance between eicosanoid biosynthesis and degradation in endometriosis patients. Both peritoneal macrophages and endometriotic lesions may be involved. Research into new molecules inhibiting biosynthetic enzymes (such as sPLA(2)-IIA and mPGES-1) and/or activating catabolic enzymes (such as 15-PGDH) may prove to be a major field of investigation in the development of targeted medical therapies.

Cryopreservation of ovarian tissue: an overview

Advances in the diagnosis and treatment of childhood, adolescent and adult cancer have greatly increased the life expectancy of premenopausal women with cancer. The ovaries are very sensitive to cytotoxic treatment, especially to alkylating agents. The only established method of fertility preservation is embryo cryopreservation according to the Ethics Committee of the American Society for Reproductive Medicine (2005), but this option requires the patient to be of pubertal age, have a partner or use donor sperm, and be able to undergo a cycle of ovarian stimulation, which is not possible when the chemotherapy has to be initiated immediately or when stimulation is contraindicated according to the type of cancer. For patients who need immediate chemotherapy, cryopreservation of ovarian tissue is the only possible alternative. This manuscript reports the techniques and results of orthotopic transplantation of cryopreserved ovarian tissue. Among almost 30 cases reported in the literature, seven live births have been achieved to date.

Evaluation of estrogen treatment in an immunodeficient mouse endometriosis model

BACKGROUND/AIMS

Endometriosis is known to be an estrogen-dependent disease. However, only a few studies have analyzed the effect of estrogen treatment in mice xenotransplanted with human endometrium. The objective of this study was to adapt a previously developed heterologous murine model to the study of estrogens and test the impact of estrone treatment on endometriosis development.

METHODS

Human proliferative endometrium was xenotransplanted into the peritoneal cavity of castrated immunodeficient mice. These mice were treated with estrogens by means of subcutaneous estrone-releasing pellets. The effect of estrone on estradiol level, uterine histology and endometriosis development was evaluated after 21 days.

RESULTS

Bioactivity of estrone pellets and their metabolization into estradiol were demonstrated. However, there was no impact on endometriosis development (no difference in lesion number, weight, size or fluorescence). This lack of response was not due to absence of estrogen receptor expression, since strong expression was found in all lesions harvested. Surprisingly, castrated nontreated mice presented with lesions showing high proliferative activity, similar to lesions found in treated mice (around 30%).

CONCLUSION

The high proliferation observed in lesions recovered from ovariectomized nontreated mice questions the utility of using estrogens in heterologous murine models.

Laparoscopic management of endometriomas using a combined technique of excisional (cystectomy) and ablative surgery

OBJECTIVE

To describe and evaluate a new technique of laparoscopic treatment of endometriomas that combines excisional and ablative surgery.

DESIGN

Descriptive and prospective study.

SETTING

Gynecology research unit in a university hospital.

PATIENT(S)

Fifty-two women under 35 years of age presenting for infertility and/or pelvic pain with endometriomas larger than 3 cm were included in the study. None had undergone any surgery for endometriosis.

INTERVENTION(S)

A large part of the endometrioma wall was first excised according to the cystectomy technique. After this first step, CO(2) laser was used to vaporize the remaining 10%-20% of the endometrioma wall close to the hilus.

MAIN OUTCOME MEASURE(S)

The feasibility of this new technique was assessed. Ovarian volume and antral follicle count (AFC) were compared between operated ovaries and nonoperated ovaries of patients with endometriosis and controls (women with male factor infertility).

RESULT(S)

The combined technique was possible in all cases. The volume of the ovary after the combined technique was similar to that of the contralateral normal ovary, as well as to that observed in infertile women without endometriosis presenting for male factor infertility. The AFC on day 2-5 showed the same number of antral follicles in all subgroups. Histopathology of the excised part of the endometrioma revealed the presence of follicles in only one case (2%). The pregnancy rate was 41% at a mean follow-up of 8.3 months. Recurrence of a small endometrioma was observed in only one case (2%).

CONCLUSION(S)

The combined technique (stripping and ablation) has proved not to be deleterious to the ovary.

A series of 3190 laparoscopic hysterectomies for benign disease from 1990 to 2006: evaluation of complications compared with vaginal and abdominal procedures

OBJECTIVE

The aim of this study was to evaluate the complication rate after laparoscopic total hysterectomy and laparoscopic subtotal hysterectomy (LASH) in case of benign disease.

DESIGN

All complications were prospectively recorded at the time of surgery and analysed retrospectively.

SETTING

University hospital.

POPULATION

Among 4505 hysterectomies performed by the same team using the same techniques between 1990 and 2006, 3190 were performed by laparoscopy, 906 by the vaginal route and 409 by laparotomy.

METHODS

Laparoscopic hysterectomies, defined as laparoscopic subtotal hysterectomy (LASH) and total laparoscopic hysterectomy [laparoscopy-assisted vaginal hysterectomy (LAVH) switched to total laparoscopic hysterectomy (TLH) in 2000], were compared with vaginal and abdominal hysterectomies.

MAIN OUTCOME MEASURES AND RESULTS

Since the early 1990s, the number of laparoscopic procedures has continued to grow, while the number of abdominal and vaginal procedures has decreased. Both minor complications (fever >38.5 degrees C after 2 days, bladder incision of <2 cm and iatrogenic adenomyosis) and major complications (haemorrhage, vesicoperitoneal fistula, ureteral injury, rectal perforation or fistula) have been observed during the surgical procedure itself and postoperatively. In the LASH group (n = 1613), the minor complication rate was 0.99% (n = 16) and the major complication rate 0.37% (n = 6). In the total laparoscopic hysterectomy (LAVH/TLH) group (n = 1577), the minor complication rate was 1.14% (n = 18) and the major complication rate 0.51% (n = 8). In the vaginal hysterectomy group (n = 906), minor and major complication rates were 0.77% (n = 7) and 0.33% (n = 3), respectively. In the abdominal hysterectomy group (n = 409), minor and major complication rates were 0.73% (n = 3) and 0.49% (n = 2), respectively.

CONCLUSION

The results from our series of 4505 women clearly show that, in experienced hands, laparoscopic hysterectomy is not associated with any increase in major complication rates.