P–067 Utility of evaluating semen samples from adolescents with Klinefelter Syndrome for cryopreservation: A multi-institution evaluation

Study question

Should physicians continue to evaluate semen analysis from adolescents with Klinefelter Syndrome for fertility preservation?

Summary answer

In the largest multi-institutional retrospective database to-date for this patient population, no sperm was found in ejaculate for cryopreservation amongst adolescent males with Klinefelter Syndrome.

What is known already

Klinefelter Syndrome is the most common genetic condition leading to male infertility and non-obstructive azoospermia. The condition causes decreased testicular growth, leading to lower production of testosterone and resulting deficiencies in secondary sexual characteristics. While testosterone therapy may be required for hypogonadism, there may be impact on future fertility potential. Current practice is to have KS adolescent patients provide semen analyses to identify potential sperm for cryopreservation. While the incidence is low, current epidemiological studies have been with limited sample size.

Study design, size, duration

This was a retrospective study of all adolescent Klinefelter Syndrome patients seen at the male infertility clinics of two large academic institutions between the years of 2015 to 2020. Adolescence was defined as the ages of 10 – 19 years old, as per the World Health Organization.

Participants/materials, setting, methods

A total of 116 patients were identified for the retrospective study database. Demographic information including weight, height, comorbidities, concurrent medications were collected. Hormone levels such as FSH, LH, testosterone, and estrogen were included for 77 patients. Additionally, semen analyses were available for 49 patients. Main results and the role of chance: Of the 49 patients with semen analyses, only 3 patients had rare sperm in ejaculate not sufficient for cryopreservation while the remaining had azoospermia. The average ejaculate volume of the provided semen samples was 0.9 cc. The average serum total testosterone level of adolescent Klinefelter Syndrome patients was 236 ng/dL. As expected, gonadotropin levels were found to be elevated (mean: 18.47 IU/L for FSH and 9.12 IU/L for LH).

Limitations, reasons for caution

The main limitation for this study was the sample size.

Wider implications of the findings: The findings from the largest retrospective study of this patient population imply a need to revisit counseling regarding the need for semen analyses in adolescent Klinefelter Syndrome patients.

Trial registration number

Not applicable

Apoptotic-induced cleavage shifts HuR from being a promoter of survival to an activator of caspase-mediated apoptosis

Little is known about the cellular mechanisms modulating the shift in balance from a state of survival to cell death by caspase-mediated apoptosis in response to a lethal stress. Here we show that the RNA-binding protein HuR has an important function in mediating this switch. During caspase-mediated apoptosis, HuR is cleaved to generate two cleavage products (CPs). Our data demonstrate that the cleavage of HuR switches its function from being a prosurvival factor under normal conditions to becoming a promoter of apoptosis in response to a lethal stress. In the absence of an apoptotic stimuli, HuR associates with and promotes the expression of caspase-9 and prothymosin α (ProT) mRNAs, and pro- and antiapoptotic factors, respectively, both of which have been characterized as important players in determining cell fate. During the early steps of caspase-mediated apoptosis, however, the level of caspase-9 protein increases, while ProT remains unchanged. Under these conditions, the two HuR-CPs selectively bind to and stabilize caspase-9 mRNA, but do not bind to ProT. Hence, taken together, our data show that by maintaining a threshold of expression of proapoptotic factors such as caspase-9 in response to a lethal stress, the HuR-CPs help a cell to switch from resisting death to undergoing apoptosis.