A joint research team from DGIST, Kyungpook National University Chilgok Hospital, and Dongguk University, both in Seoul, South Korea has revealed the identity of cervical stem cells for the first time in the world.
Cervical cancer is the fourth most common cancer among women worldwide, with approximately 600,000 cases occurring annually. The main cause is the human papillomavirus (HPV), and its incidence rate has declined sharply in developed countries due to vaccination efforts. However, in developing countries where providing vaccination is challenging, cervical cancer remains prevalent, highlighting the need for new prevention methods.
Lactic acid bacteria are known to be the most abundant beneficial bacteria in a woman's vagina. Previously, it was only known to inhibit already developed cervical cancer cells, but this study revealed a new mechanism through which lactic acid bacteria inhibit cancer progression in the pre-cancerous stage.
The research team has developed the world's first method to evaluate the regenerative capacity of stem cells by transplanting human stem cells into the tongues of immunosuppressed mice. They also established normal and pre-cancerous cervical organoid models and identified the identity and differentiation process of human cervical stem cells.
An organoid is a three-dimensional cell culture model that mimics the structure and function of a specific organ or tissue by culturing stem cells. It can be used to study human tissue development processes or disease mechanisms, as well as for new drug development and precision medicine.
Utilising this approach, the research team ascertained that HPV is the primary aetiological agent of cervical cancer, given its propensity to promote the proliferation of progenitor cells that have already initiated the differentiation process, rather than stem cells.
A progenitor cell is a cell at an intermediate stage of differentiation from a stem cell. It has the ability to differentiate into a specific tissue or cell but has a limited capacity for self-replication. Progenitor cells are positioned at the intermediate stage between fully differentiated mature cells and stem cells and play an important role in tissue regeneration and growth.
Furthermore, lactic acid bacteria were found to secrete lactic acid, which impedes the effects of the virus and inhibits not only the self-replication of normal stem cells but also the initial process of transformation from stem cells to cancer cells.
“Through this study, we have found that lactic acid bacteria play an important role in maintaining cervical health and preventing the occurrence of cervical cancer,” said Prof. Jeong Youngtae of the Department of New Biology at DGIST. “We hope this research will contribute to the development of technologies for preventing cervical cancer.”
Published in Nature Communications, the research presents new possibilities for cervical cancer prevention and treatment using lactic acid bacteria and lactic acid.