Combining Hormone Replacement Therapy with Chemotherapy for Ovarian Cancer Treatment

Chinese & English Text │ Debby Seng
Photo │ Editorial Board with some provided by the interviewee

Faculty of Health Sciences Associate Professor Di Lijun and his team have discovered, through meta-analysis, that supplementing estrogen (hormonere placement therapy, or HRT) to ovarian cancer patients with ovariectomy(surgical removal of one or both ovaries) may help improve the effectiveness of chemotherapy and make recurrence less likely. To some extent, this finding is distinct from conventional assumptions of ovarian cancer therapy.

To some extent, the finding of Prof Di Lijun’s research is distinct from conventional assumptions of ovarian cancer therapy

Scholars know that the level of estrogen and the risk for ovarian and breast cancer are positively correlated. In clinical practice, the application of estrogen agonist in treating the estrogen receptor‑positive breast cancer has achieved remarkable success. (editor’s note: the estrogen receptor, or ER, is the factor that mediates the estrogen effect inside the cell.) However, the same method has shown an unsatisfactory effect in treating ovarian cancer which, in most cases, is also ER‑positive. Prof Di’s team has found that the difference is caused by the distinct behaviour of ER, which forms a complex with the C‑terminal binding protein (CtBP) in ovarian cancer cells and inhibits the expression of DNA damage repair (DDR) genes.

Prof Di Lijun’s research shows that hormone replacement therapy may help improve the effectiveness of chemotherapy

Prof Di points out that treating ovarian cancer often involves ovariectomy followed by chemotherapy. However, if the patient’s ovaries, which produce estrogen, are removed during surgery, complications may occur due to the lack of estrogen. In clinical practice, supplementing estrogen, or HRT, is not recommended to reduce the symptoms associated with ovariectomy because estrogen might influence the effect of cancer therapy and increase the risk of cancer relapse. Prof Di says: ‘Our data show that estrogen is able to reduce the DDR capacity of cancer cells. More importantly, combining estrogen with chemotherapy is a more effective way to kill cancer cells than using chemotherapy alone, suggesting that supplementing estrogen will benefit the chemotherapy of ovarian cancer patients.’ He further comments that:‘In fact, the ovarian cancer patients who happened to receive the HRT showed better survival rates according to some of the previous studies, which is consistent with our conclusion.’

Before joining the University of Macau, Prof Di Lijun was a visiting fellow at the National Institutes of Health in the United States. He focuses on the mechanisms of transcriptional regulation of gene expression and gene expression regulatory network. He is also interested in understanding the mechanisms of human diseases such as cancer, by exploring the aberrant gene expression associated with these diseases.

ISSUE 22 | 2020

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