UU_12023/29). Richard Riley and Kym Snell are supported by funding from the Evidence Synthesis Working Group, which is funded by the National Institute for Health Research School for Primary Care Research (NIHR SPCR) \[Project Number 390\]. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, or the Department of Health and Social Care. We acknowledge all researchers, research nurses, and staff of the participating centers in the trials contributing to the International Weight Management in Pregnancy (i‐WIP) IPD meta‐analysis and all members of i‐WIP Collaborative Group. We thank two anonymous reviewers and the Associate Editor for their constructive comments that helped improve the article upon revision.


Introduction
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Osteosarcoma is an aggressive malignancy primarily occurring in the bone of both children and adults. Although primary bone cancers account for less than 0.2% of all cancers,[@b1-ott-10-5355] their frequency has kept increasing by 0.3% annually over the past decade according to the National Cancer Institute SEER program.[@b2-ott-10-5355] The clinical treatment of osteosarcoma involves chemotherapy in combination with surgery. Depending on the success of therapy, the 5-year survival rates of patients with localized tumors have increased ranging from 60% to 80%, while patients with detectable metastases at the time of diagnosis or recurrences usually have poor prognoses, with reports of 5-year survival rates as low as 19%.[@b3-ott-10-5355]--[@b6-ott-10-5355] In addition, many targeted therapies have been tried over the past 20 years.[@b7-ott-10-5355] However, these therapeutic strategies have had minimal beneficial effects on the improvement of survival outcomes.[@b7-ott-10-5355]--[@b10-ott-10-5355] This is primarily due to the fact that the genetic etiology of osteosarcoma is extremely heterogeneous and has not been fully understood.[@b11-ott-10-5355] Thus, the identification of new molecule targets is urgently needed for the improvement