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Updated: Jan 27, 2026
An Orthotopic Murine Model of Human Prostate Cancer Metastasis
Published on: September 18, 2013
Replication Study: The microRNA miR-34a inhibits prostate cancer stem cells and metastasis by directly repressing
Xuefei Yan1, Beibei Tang1, Biao Chen1
1Crown Biosciences Inc, Science & Technology Innovation Park, Taicang, China.
Abstract:
As part of the Reproducibility Project: Cancer Biology, we published a Registered Report (Li et al., 2015), that described how we intended to replicate selected experiments from the paper 'The microRNA miR-34a inhibits prostate cancer stem cells and metastasis by directly repressing CD44' (Liu et al., 2011). Here we report the results. We found the microRNA, miR-34a, was expressed at twice the level in CD44+ prostate cancer cells purified from xenograft tumors (LAPC4 cells) compared to CD44- LAPC4 cells, whereas the original study reported miR-34a was underexpressed in CD44+ LAPC4 cells (Figure 1B; Liu et al., 2011). When LAPC4 cells engineered to express miR-34a were injected into mice, we did not observe changes in tumor growth or CD44 expression; however, unexpectedly miR-34a expression was lost in vivo. In the original study, LAPC4 cells expressing miR-34a had a statistically significant reduction in tumor regeneration and reduced CD44 expression compared to control (Figure 4A and Supplemental Figures 4A,B and 5C; Liu et al., 2011). Furthermore, when we tested if miR-34a regulated CD44 through binding sites in the 3'UTR we did not find a statistically significant difference, whereas the original study reported miR-34a decreased CD44 expression that was partially abrogated by mutation of the binding sites in the CD44 3'UTR (Figure 4D; Liu et al., 2011). Finally, where possible, we report meta-analyses for each result.
Insights
This study attempted to replicate findings on microRNA miR-34a
Area of Science:
- Oncology
- Molecular Biology
- Gene Regulation
Background:
- The microRNA miR-34a was previously reported to inhibit prostate cancer stem cells and metastasis by repressing CD44.
- A Registered Report outlined the intention to replicate key experiments from the original study.
Purpose of the Study:
- To replicate experiments investigating the role of miR-34a in prostate cancer stem cells and metastasis.
- To verify the regulatory relationship between miR-34a and CD44 expression.
Main Methods:
- Replication of experiments involving miR-34a expression in CD44+ and CD44- prostate cancer cells (LAPC4).
- In vivo studies injecting LAPC4 cells engineered to express miR-34a into mice.
- Reporter assays to assess miR-34a regulation of CD44 via 3'UTR binding sites.
- Meta-analyses were performed where applicable.
Main Results:
- miR-34a was found to be overexpressed in CD44+ LAPC4 cells, contrary to the original study's findings.
- No significant changes in tumor growth or CD44 expression were observed when miR-34a was introduced into LAPC4 cells in vivo; miR-34a was lost in vivo.
- No statistically significant evidence supported miR-34a regulating CD44 through its 3'UTR binding sites, differing from the original study.
Conclusions:
- The results of this replication attempt diverge significantly from the original study's findings regarding miR-34a's role in prostate cancer.
- The regulatory mechanism of miR-34a on CD44 in prostate cancer stem cells and metastasis requires further investigation.
- Discrepancies highlight the importance of reproducibility in cancer biology research.
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