Oestrogen dose tapering during luteal phase does not affect clinical outcomes after hormone replacement treatment-frozen-thawed embryo transfer cycles: a retrospective analysis.

STUDY QUESTION: Does oestrogen dose tapering during the luteal phase affect the clinical outcome after hormone replacement treatment-frozen-thawed embryo transfer (HRT-FET) cycles? SUMMARY ANSWER: Our results suggest that tapering oestrogen doses during the luteal phase results in similar clinical outcomes to those obtained with the traditional luteal phase support (LPS). WHAT IS KNOWN ALREADY: Traditional LPS with oestrogen and progesterone is considered necessary in HRT-FET cycles. However, case reports have shown successful clinical pregnancies and live births in the absence of oestrogen administration after embryo transfers. STUDY DESIGN, SIZE, DURATION: This was a retrospective study on 6035 HRT-FET cycles extending over 7 years from January 2011 to June 2018 at the reproductive medicine centre of Xiangya Hospital. PARTICIPANTS/MATERIALS, SETTING, METHODS: We compared the clinical outcomes of 1632 HRT-FET cycles with tapered oestrogen doses from 12 days after embryo transfer (study group) to those of 4403 HRT-FET cycles maintained on constant oestrogen doses during the luteal phase (control group) in the case of positive serum HCG test. MAIN RESULTS AND THE ROLE OF CHANCE: We found similar biochemical pregnancy rates (52.1% vs. 51.9, P = 0.864), clinical pregnancy rates (44.9% vs. 43.2%, P = 0.249), implantation rates (29.8% vs. 29.3%, P = 0.591) and miscarriage rates (16.0% vs. 14.6%, P = 0.379) between the studied groups. LIMITATIONS, REASONS FOR CAUTION: Retrospective, design-associated biases are possible. In addition, some baseline characteristics differed between groups. Finally, we did not compare live birth rates between groups. WIDER IMPLICATIONS OF THE FINDINGS: Our study showing similar outcomes between traditional LPS and oestrogen tapering during the luteal phase indicates that oestrogen may be cautiously tapered during the luteal phase after HRT-FET cycles. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (grant no. 81401269) and the class General Financial Grant from the China Postdoctoral Science Foundation (grant no. 2017M620360). The authors declare that they have no competing interests. TRIAL REGISTRATION NUMBER: N/A.

PPDPF Promotes the Progression and acts as an Antiapoptotic Protein in Non-Small Cell Lung Cancer.

Resistance to radiotherapy is frequently observed in the clinic and leads to poor prognosis of non-small cell lung cancer (NSCLC). How to overcome resistance to radiotherapy is a challenge in the treatment of NSCLC. In this study, PPDPF was found to be upregulated in NSCLC tissues and cell lines, and its expression negatively correlated with the overall survival of patients with NSCLC. PPDPF promoted the growth, colony formation and invasion of lung cancer cells. Moreover, knockout of PPDPF inhibited tumorigenesis in the KL (KrasG12D; LKB1f/f) mouse model of lung cancer. Additionally, overexpression of PPDPF led to radioresistance in lung cancer cells, and knockdown of PPDPF sensitized lung cancer cells to radiotherapy. Mechanistically, PPDPF interacted with BABAM2 (an antiapoptotic protein) and blocked its ubiquitination by MDM2, thus stabilizing BABAM2 and promoting the radioresistance of lung cancer cells. Our present study suggested PPDPF as a therapeutic target in NSCLC.