Animal studyindependent cross-checkabstract checked I-CHM-117 standard review
Tumour scar tissue can hold cancer back
Stromal elements act to restrain, rather than support, pancreatic ductal adenocarcinoma.
Overview
Rhim AD et al.. Cancer Cell 2014 · PMID 24856585 · DOI 10.1016/j.ccr.2014.04.021
In mice, removing the scar-like stroma around pancreatic tumours made them more aggressive.
Does the study support the specific claim? No · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Test the role of tumour stroma
- How was the study done?
Mouse experiments
- How many people, animals or samples were studied?
Mouse pancreatic cancer model
- What was actually found?
Stroma restrains tumour growth
- How large was the observed effect?
Not applicable
- What do the results mean in everyday life?
Fibrosis is not simply the enemy
- What are the study's limitations?
Animal model
- What does it say about Elawady's specific claim?
Contradicts the simple fibrosis explanation
- Do the results apply to Germany and Europe?
Low
- What can explicitly not be concluded from this study?
Cannot be applied directly to patients
Scientific in-depth review
1. Full reference
- Authors
- Rhim AD et al.
- Journal
- Cancer Cell
- Year
- 2014
- Identifier
- PMID 24856585 DOI 10.1016/j.ccr.2014.04.021
- Verification
- verified – PubMed efetch 2026-10-26 (PublicationType and CommentsCorrections checked); Crossref 2026-10-26
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
NIH grants.
2. Research question
What is the role of Hedgehog-driven desmoplastic stroma in pancreatic cancer progression?
3. Study design and population
- Study design
- Animal study – Genetically engineered mouse model study
- Population
Mouse model of pancreatic ductal adenocarcinoma
- Country
USA
- Period
Not stated
- Sample size
Not stated in abstract
- Inclusion and exclusion criteria
Mouse PDAC model
4. Methods and endpoints
- Exposure / intervention
Deletion of Shh / Smoothened inhibitor (stroma depletion)
- Comparator
Stroma-intact tumours
- Endpoints
Tumour aggressiveness, histology, vascularity, survival
- Statistical methods
Not stated in abstract
5. Actual results
- Results
Shh-deficient tumours had less stroma but were more aggressive, undifferentiated, more vascular and proliferative; a Smoothened inhibitor reproduced this; VEGFR blockade improved survival of Shh-deficient tumours.
- Absolute risks
not applicable (animal study)
- Authors' conclusion
Some components of tumour stroma can act to restrain tumour growth.
6. Strengths
- Genetic and pharmacological approaches agree
7. Weaknesses
- Mouse model; one tumour type
8. Risk of bias
- Orienting tool
- none applicable
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- not assessable
- Rationale
Animal study.
9. Assessment of the statistical interpretation
Not applicable.
10. Relevance to the specific claim
Contradicts the claim that fibrotic stroma simply drives cancer: removing stroma made tumours more aggressive.
11. Independent contrary findings
Olive 2009 (I-CHM-11) and Meads 2009 (I-CHM-119): stroma can impede drug delivery or protect cells.
12. Transferability to Germany and Europe
Basic biology.
13. Overall methodological judgement
Shows stroma has dual roles.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | not assessable |
| Precision of results | not applicable |
| Directness | very indirect |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | low |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Human relevance.
15. Linked fact checks
- Cancer cells resist chemotherapy because of their fibrotic interstitial (stromal) environment; fibrosis strangles cells, which then turn cancerous and resist chemo and radiation. – Studies contradicting or limiting the claim