Quantitative mass spectrometry identifies drug targets in cancer stem cell-containing side population.

Steiniger SC, Coppinger JA, Krüger JA, Yates J 3rd, Janda KD

Stem cells (Dayton, Ohio)18 Sept 2008Cited by 37 (Europe PMC)

PMID18802034PMCIDPMC2745975DOI10.1634/stemcells.2008-0397PepBankPUB-18802034

Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study2

No result from this study comes from a test of the peptide.

Natural levels measured1

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

01LabEndogenous levelIn vitro (cells)Mechanism
In breast cancer cell lines, thymosin beta4 expression was elevated in side population cells compared with non-side population cells, as validated by Western blot.
In plain wordsIn cells, the body's own thymosin beta4 level was higher in cancer stem cell-rich cells than in other cells.
Peptide
Thymosin beta-4 (human)
Outcome
IncreaseTB4 protein level in side population cells
Study
n: not reported in source
MCF7 and MDA-MB231 breast cancer cell lines
Comparator
Non-side population cells
Outcome group
Tumor growth · Cancer
Source sentences
Summary
Furthermore, functional validation provided clear evidence that elevated TB4 expression contributes to drug resistance in the stem cell population.
1 context sentence(design, population, supporting numbers)
Summary · context
The differential levels of three of these proteins, thymosin beta4 (TB4), proliferation-associated protein 2G4, and SIAH-interacting protein, were validated using Western blot.
This result measures the body's own Thymosin beta-4 (human). Nobody was given the peptide. It is not evidence about taking it.
Report a problemFND-1880203401

Studies that did not test the peptide alone1

In this study, Thymosin beta-4 (human) was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking Thymosin beta-4 (human).

02LabNot a test of Thymosin beta-4 (human) aloneIn vitro (cells)Mechanism
In two breast cancer cell populations, siRNA silencing of TB4 led to a loss of chemoresistance.
In plain wordsIn cells, switching off thymosin beta4 made two breast cancer cell types lose their resistance to chemotherapy.
Peptide
Thymosin beta-4 (human)
Outcome
DecreaseChemoresistance after TB4 siRNA silencing
Study
n: not reported in source
MCF7 and MDA-MB231 breast cancer cell lines
Comparator
Cells without TB4 silencing
Outcome group
Tumor growth · Cancer
Source sentences
Summary
Small interfering RNA silencing of TB4 led to a loss of chemoresistance in two separate breast cancer populations.
1 context sentence(design, population, supporting numbers)
Summary · context
compare and identify proteins with differential expression profiles between side population cells, know to be enriched in cancer stem cells, and nonside population cells, which are depleted in cancer stem cells, for two breast cancer cell lines, MCF7 and MDA-MB231
In this study, Thymosin beta-4 (human) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Thymosin beta-4 (human).
Report a problemFND-1880203402

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
13 Oct 2026, 01:52 UTC
Study results updated
Version 1
12 Oct 2026, 18:17 UTC
First added · source update from Europe PMC

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