Chemotherapy in testicular cancer patients can cause DNA changes in sperm

• Four years after cancer treatment, most patients recover sperm concentration and motility, but little was known about how the treatment affects the epigenetics of human sperm, the mechanism that modifies genes and has the ability to activate or silence their expression
• This study, the largest conducted to date, suggests changes occurred in the sperm methylome of testicular cancer survivors based on samples taken before and after cancer treatment. This finding lays the foundation for further study of the possible consequences of this alteration in the genetic information of sperm
• Testicular cancer has a low incidence (1%) and a high survival rate (95%). It is most common in men aged 20 to 34, during peak fertility years, which is why experts always recommend freezing a couple of samples preventatively before starting treatment

Amsterdam, JULY 08th, 2024

Scientific literature has shown that four years after cancer treatment, sperm typically regain their pre-treatment characteristics. However, until now, there were limited data available in humans regarding how these drugs might affect the sperm epigenome. These chemical compounds that bind to DNA (genome) can modify genes, activating or silencing their expression.

The study “Sperm DNA methylome changes in testicular cancer patients following chemotherapy treatment,” presented at the 40th Annual Meeting of the European Society of Human Reproduction and Embryology (ESHRE) in Amsterdam, examines the consequences of chemotherapy treatment commonly prescribed for testicular cancer.

“The results were clear: after isolating sperm DNA, the functional enrichment analysis of the affected genes identified 65 differentially methylated regions. Specifically, the study revealed that the most affected biological processes were the regulation of macromolecule biosynthetic processes, hormone receptor binding, and signaling pathways that regulate stem cell pluripotency and cancer pathways”, comments Dr. Marga Esbert, biologist and research coordinator at IVI Barcelona.

This is the most extensive study conducted to date on testicular cancer survivors. To ensure comparability, all the samples studied were frozen—both those taken before cancer treatment and those taken after recovery—since cryopreservation can alter the epigenetics of sperm samples.

“We knew that cancer treatments in general and chemotherapy, in particular, could cause damage to sperm DNA integrity and aneuploidy, but that this damage was repaired after a few years. With this new study, we have seen that the epigenetics of sperm also change after overcoming testicular cancer, but these modifications persist even four years later”, clarifies Dr. Esbert. 

Testicular cancer has a low incidence (1%) and a high recovery rate of around 95%. Naturally, one of the main concerns for patients is the ability to father children after overcoming cancer. Therefore, specialists always recommend thorough counseling in collaboration with oncologists to ensure that seminal genetic information remains intact after chemotherapy. “This step is crucial, as the age range for this type of cancer nearly coincides with peak fertility years, from 20 to 34 years old. Informing the patient at the oncology consultation at the time of diagnosis is key to preserving intact genetic material throughout the prescribed cancer treatment process”, concludes the doctor.

About IVI RMA Global

IVI was established in 1990 as the first medical institution in Spain dedicated exclusively to Human Reproduction. Since then, it has helped bring over 250,000 children into the world through continuous innovation and the implementation of the most advanced assisted reproduction treatments.

It is one of the European centers with the highest pregnancy rates; in fact, the majority of couples who consult IVI for infertility issues achieve their goal. Moreover, it boasts a team of over 2,500 professionals, including some of the world’s leading specialists in assisted reproduction.

IVI is part of the IVI RMA Global group, present in 15 countries. In addition to Spain, it has clinics in Portugal, Italy, the Czech Republic, the Nordic countries, the United Kingdom, the USA, Canada, Panama, Brazil, and Chile.