## Registered report: the microRNA miR-34a inhibits prostate cancer stem cells and metastasis by directly repressing CD44 <br> **Abstract** The [Reproducibility Project: Cancer Biology][1] seeks to address growing concerns about reproducibility in scientific research by conducting replications of selected experiments from a number of high-profile papers in the field of cancer biology. The papers, which were published between 2010 and 2012, were selected on the basis of [citations and Altimetric scores][2] ([Errington et al., 2014][3]). This Registered report describes the proposed replication plan of key experiments from "The microRNA miR-34a inhibits prostate cancer stem cells and metastasis by directly repressing CD44" by Liu and colleagues published in *Nature Medicine* in 2011 ([Liu et al., 2011][4]). Liu and colleagues first demonstrated that miR-34a levels were reduced in CD44+ prostate cancer cells (Figure 1B). They then showed that xenograft tumors from cells expressing exogenous miR-34a were smaller in size than control tumors (Supplemental Figure 5C). Tumors with exogenous miR-34a showed reduced levels of CD44 expression (Figure 4A), and mutation of two putative miR-34a binding sites in the CD33 3′ UTR partially abrogated signal repression in a luciferase assay (Figure 4D). The Reproducibility Project: Cancer Biology is a collaboration between the [Center for Open Science][5] and [Science Exchange][6], and the results of the replications will be published by [*eLife*][7]. ---------- ### Contents This component contains additional materials relating to the Registered Report for Study 28: Liu et al., 2011 (*Nature Medicine*). The Registered Report can be found [here][8]. **Registered Report Initial Draft**: - This document represents the first draft of the selected experimental protocols. It contains the information that the Core team, with help from scientist volunteers, was able to glean from the original publication and its supplemental materials before the original authors were contacted for their input. - [Study 28 Registered Report Initial Draft][9] **Data Estimation**: - When original data was unable to be obtained, or original qualitative data was quantified (for example, Western blots), the estimated data is contained here. Examples include densitometric quantification of Western blot bands, or estimations of means and variances from published graphs. - [Study 28 Figure 1B data estimation][10] - [Study 28 Figure 1B data estimation][11] **Power Calculations**: - These documents contain details about how power calculations were performed, and include spreadsheets documenting statistical tests as well as any PRISM files, R scripts or additional materials used. - [Study 28 Power Calculations][12] - [Study 28 Protocol 4 one-way ANOVA.R][13] - [Study 28 Protocol 4 unequal variance t-tests.R][14] [1]: https://osf.io/e81xl/wiki/home/ [2]: https://osf.io/e81xl/wiki/studies/ [3]: https://elifesciences.org/content/3/e04333 [4]: https://doi.org/10.1038/nm.2284 [5]: https://cos.io/ [6]: https://www.scienceexchange.com/ [7]: https://elifesciences.org/ [8]: http://elifesciences.org/content/4/e06434 [9]: https://osf.io/gk9e6/ [10]: https://osf.io/2p4vm/ [11]: https://osf.io/i482j/ [12]: https://osf.io/rvzju/ [13]: https://osf.io/aue3k/ [14]: https://osf.io/ep3j6/