Cryopreservation and fertility: current and prospective possibilities for female cancer patients

Human recombinant FSH induces chemoresistance in human breast cancer cells via HIF-1α activation†

Breast cancer patients under 40 years of age who are candidate to chemotherapy with alkylating drugs may undergo controlled ovarian stimulation (COS) with recombinant human follicle-stimulating hormone (rhFSH) in order to get fertility preservation by mature oocyte cryostorage. The direct effect(s) of exogenous rhFSH on the chemosensitivity of breast cancer is currently unknown. To clarify this issue, we incubated four different breast cancer cell lines with rhFSH (10 IU/L, 24 h) and then we exposed them to doxorubicin (DOX) or cyclophosphamide (CPA). The effect(s) of rhFSH on human breast cancer cells treated with DOX or CPA was measured in terms of (1) cell viability, (2) cytotoxicity, (3) multidrug resistance (MDR) genes and proteins expression and activities, and (4) hypoxia-inducible factor 1-alpha (HIF-1α) activation. Pretreatment with rhFSH significantly increased the viability of breast cancer cells after treatment with DOX or CPA, and reduced the lactate dehydrogenase leakage and reactive oxygen species production. Moreover, after preincubation with rhFSH, the MDR proteins (Pgp, MPR1, and BCRP) expression and activity resulted upregulated and the HIF-1α pathway activated. In addition, the use of a widely used HIF-1α inhibitor, the 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1), prevented the rhFSH effect on the onset of MDR. Taken together, these observations suggest that a short exposure to rhFSH induces chemoresistance to DOX and CPA in human breast cancer cells via HIF-1α activation.

A new thiocyanoacetamide (2-cyano-2-p-nitrophenyl-N-benzylthioamide) reduces doxorubicin-induced in vitro toxicity in Sertoli cells by decreasing apoptosis and autophagy

Despite conflicting data on doxorubicin (DOX) reproductive toxicity, its chemotherapeutic potential sustains its use to treat different types of cancer. This work was designed to study the protective effect of a newly synthesized thiocyanoacetamide (TA), in comparison with selenium (Se), against doxorubicin-induced in vitro toxicity in rat Sertoli cells (SCs). DOX was administered alone or in combination with Se or TA. The possible protective role of increased concentrations of TA (0.25, 0.5 and 1 mM) or Se (12, 25 and 50 μM) on SCs was tested against 1 μM of DOX. From this screening, only the least toxic doses of TA and Se were used for further analysis. DOX cytotoxicity, as well as its impact on SCs viability, mitochondrial membrane potential (ΔΨ_m), oxidative stress biomarkers, apoptosis and autophagy were assessed. Our results showed that DOX exerted its cytotoxic effect through a significant increase in cell death. DOX-mediated cell death was not related to autophagy nor to an overproduction of reactive oxygen species. It was rather due to apoptosis, as shown by the increased number of apoptotic cells and increased activity of caspase-3, or due to necrosis, as shown by the increase in lactate dehydrogenase (LDH) extracellular activity. Still, Bax and Bcl-2 protein expression levels, as well as ΔΨ_m were not altered by the different treatments. Some individual doses of Se or TA induced a significant toxicity in SCs, however, when combined with DOX, there was a decrease in cell death, LDH extracellular activity, number of apoptotic cells and caspase-3 activity. Overall, our results indicate that DOX-mediated apoptosis in cultured SCs can possibly be averted through its association with specific doses of Se or TA. Nevertheless, TA showed a higher efficiency than Se in reducing DOX-induced toxicity in SCs by decreasing not only apoptosis, but also necrosis and autophagy.

Impact of vitrification on human oocytes before and after in vitro maturation: A systematic review and meta-analysis

OBJECTIVE

There are controversies regarding in vitro maturation (IVM) procedure, the time of storing frozen oocytes and maturation stage of vitrified oocytes and its impact on oocytes fertilization capability. The aim of this systematic review and meta-analysis was to evaluate the impact of vitrification on human oocytes during IVM procedure.

STUDY DESIGN

A systematic review with meta-analysis was undertaken. Main search terms were those related key words. We searched Medline, Embase, Scopus and ISI web of science to detect English-language studies. The final search was performed on 27 January 2018. The original articles which studied laboratory outcomes after vitrification of MII or GV oocytes before or after IVM were included. Exclusion criteria were animal trials and the studies that performed cryopreservation using slow-freeze method. Oocyte maturation, survival, fertilization and cleavage rates were assessed. Bias and quality assessments were applied.

RESULTS

2476 articles were screened and after duplicates removing together with application of inclusion and exclusion criteria, 14 studies assessed for eligibility. Finally 5 studies included for analysis. All studies compared laboratory outcomes between oocytes that vitrified at the GV stage and those which firstly matured in vitro, and then vitrified. Meta-analysis showed that vitrification of oocytes at GV stage had a negative impact on maturation rate (RR = 1.28, 95% CI: 0.96-1.70); but not on cleavage rate (RR = 1.07, 95% CI: 0.70-1.64); fertilization rate (RR = 0.99, 95% CI: 0.85-1.14) and survival rate(RR = 1.01, 95% CI: 0.96-1.06).

CONCLUSION

In general, Based on our results, oocyte vitrification decreases the maturation rate. In addition, survival, fertilization as well as cleavage rates did not significantly differ between the oocytes vitrified before IVM versus oocytes vitrified after IVM.

Embryo Cryopreservation Following In-Vitro Maturation for Fertility Preservation in a Woman with Mullerian Adenosarcoma: A Case Report

In-vitro maturation (IVM) of the immature oocytes recovered from the surgically removed ovarian tissue has been considered as a process for fertility preservation in patients with cancer. Fertility preservation for a woman with Mullerian adenocarcinoma. A 37-year-old woman with Mullerian adenocarcinoma was a candidate for ovarian resection. The immature oocytes were retrieved after ovarian resection from a 37-year-old woman with Mullerian adenocarcinoma. The oocytes underwent IVM and were fertilized using intracytoplasmic sperm injection (ICSI). Two healthy embryos were cryopreserved for future use. The immature oocytes from the ovarian tissue can be matured with IVM for generation of embryos after ICSI. The embryos can be vitrified using routine methods for fertility preservation in young women with cancer.

Preantral follicle density in ovarian biopsy fragments and effects of mare age

The aims of the present study were to: (1) evaluate preantral follicle density in ovarian biopsy fragments within and among mares; (2) assess the effects of mare age on the density and quality of preantral follicles; and (3) determine the minimum number of ovarian fragments and histological sections needed to estimate equine follicle density using a mathematical model. The ovarian biopsy pick-up method was used in three groups of mares separated according to age (5–6, 7–10 and 11–16 years). Overall, 336 preantral follicles were recorded with a mean follicle density of 3.7 follicles per cm2. Follicle density differed (P < 0.05) among animals, ovarian fragments from the same animal, histological sections and age groups. More (P < 0.05) normal follicles were observed in the 5–6 years (97%) than the 11–16 years (84%) age group. Monte Carlo simulations showed a higher probability (90%; P < 0.05) of detecting follicle density using two experimental designs with 65 histological sections and three to four ovarian fragments. In summary, equine follicle density differed among animals and within ovarian fragments from the same animal, and follicle density and morphology were negatively affected by aging. Moreover, three to four ovarian fragments with 65 histological sections were required to accurately estimate follicle density in equine ovarian biopsy fragments.

Preserving human cells for regenerative, reproductive, and transfusion medicine

Cell cryopreservation maintains cellular life at sub-zero temperatures by slowing down biochemical processes. Various cell types are routinely cryopreserved in modern reproductive, regenerative, and transfusion medicine. Current cell cryopreservation methods involve freezing (slow/rapid) or vitrifying cells in the presence of a cryoprotective agent (CPA). Although these methods are clinically utilized, cryo-injury due to ice crystals, osmotic shock, and CPA toxicity cause loss of cell viability and function. Recent approaches using minimum volume vitrification provide alternatives to the conventional cryopreservation methods. Minimum volume vitrification provides ultra-high cooling and rewarming rates that enable preserving cells without ice crystal formation. Herein, we review recent advances in cell cryopreservation technology and provide examples of techniques that are utilized in oocyte, stem cell, and red blood cell cryopreservation.

Effects of neutral red assisted viability assessment on the cryotolerance of isolated bovine preantral follicles

PURPOSE

Fertility preservation strategies warrant non-invasive viability assessment of preantral follicles (PAF) such as staining with Neutral Red (NR) that is incorporated by viable follicles. To optimize the procedure, we firstly determined the lowest concentration and shortest exposure time needed for optimal viability screening of isolated bovine PAF. Secondly, we combined this protocol to a vitrification procedure to assess cryotolerance of the stained follicles.

METHODS

Isolated PAF (900, divided over 6 replicates) were cultured in DMEM/Ham's F12 (Culture Medium - Cm) for 4 days (38.5 °C, 5% CO2). On D0, D2 and D4, follicles were stained, by adding NR medium (NRm = Cm with different concentrations NR) after which viability was assessed by counting stained/non-stained PAF every 30 min for a period of 2 h.

RESULTS

Following a binary logistic regression analysis with staining as a result (yes/no) versus log-concentration, a probability model could be fitted, indicating that the proportion of stained follicles remained stable after 30 min when 15 μg/ml NR was used, without compromising follicular health and viability. Consequently, using this protocol, no significant effect of staining prior to vitrification, was found on PAF viability immediately after warming or following 4 days of culture.

CONCLUSIONS

In conclusion, we propose NR staining as a non-invasive, non-detrimental viability assessment tool for PAF, when applied at 15 μg/ml for 30 min, being perfectly compatible with PAF vitrification.

Preventing Microbial Contamination during Long-Term In Vitro Culture of Human Granulosa-Lutein Cells: An Ultrastructural Analysis

Purpose. To investigate whether the addition of antibiotic/antimycotic during human granulosa-lutein cells (GLCs) isolation and cell-plating procedures prevents microbial contamination after 144 h of culture and also evaluate the effects of contamination on GLCs ultrastructure and steroid secretion. Methods. GLCs obtained from five women submitted to assisted reproductive techniques (ARTs) were isolated with PBS supplemented with antibiotic/antimycotic or PBS nonsupplemented and cultured for 144 h. GLCs were evaluated by transmission electron microscopy (TEM), and estradiol (E2) and progesterone (P4) secretion was assayed by chemiluminescence. Results. Although no contaminating microorganisms were identified by light microscopy, TEM analyses revealed several bacterial colonies in culture dishes of GLCs isolated with only PBS. Bacterial contamination disrupted the adherence of the GLCs to the culture plate interfering with monolayer formation affecting the growth pattern of GLCs. Various cellular debris and bacteria were observed, and no organelles were found in the cytoplasm of infected cells. While bacterial contamination decreased estradiol media levels, it increased progesterone, as compared with noncontaminated group. Conclusion. Taken together, our data showed that the addition of a high dose of antibiotic/antimycotic during the isolation and cell-plating procedures prevents microbial contamination of long-term GLCs culture as its effects on cells growth and function in vitro.