A tumor-penetrating peptide modification enhances the antitumor activity of thymosin alpha 1.

Lao X, Liu M, Chen J, Zheng H

PloS one19 Aug 2013Cited by 26 (Europe PMC)

PMID23977262PMCIDPMC3747120DOI10.1371/journal.pone.0072242PepBankPUB-23977262

Summary

A serious limitation of numerous antitumor drugs is the incapacity to penetrate solid tumors. However, addition of an RGD fragment to peptide drugs might solve this problem. In this study, we explored whether the introduction of a permeability-enhancing sequence, such as iRGD (CRGDK/RGPD/EC) fragments, would enhance the activity of thymosin alpha 1 (Tα1). The modified Tα1 (Tα1-iRGD) was successfully expressed and purified, and the in vitro assay showed that Tα1-iRGD presented a similar activity as Tα1 in promoting proliferation of mouse splenocytes. Meanwhile, cell adhesion analysis revealed that Tα1-iRGD exhibited more specific and greater binding with tumor cells compared with Tα1. Furthermore, the iRGD fragment evidently enhanced the basal ability of Tα1 to inhibit proliferation of cancer cells in vitro, particularly of mouse melanoma cell line B16F10 and human lung cancer cell line H460. Our findings indicated that the addition of an iRGD fragment increased the anti-proliferative activity of Tα1 against cancer cells by improving the ability of Tα1 to penetrate the tumor cells. This study highlighted the important roles of an iRGD sequence in the therapeutic strategy of Tα1-iRGD. Thus, Tα1-iRGD could be a novel drug candidate for cancer treatment.

CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study4

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

Studies that did not test the peptide alone4

In this study, Thymosin alpha-1 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 alpha-1.

01LabNot a test of Thymosin alpha-1 aloneIn vitro (cells)Activity measurement
In mouse splenocytes, the Tα1-iRGD fusion promoted proliferation with activity similar to thymosin α1.
In plain wordsIn lab tests with mouse spleen cells, the modified peptide promoted cell growth about as well as thymosin α1.
Peptide
Thymosin alpha-1
Outcome
No significant changeProliferation of mouse splenocytes
Study
mousen: not reported in source
Splenocytes
Comparator
Thymosin α1
Outcome group
Immune response · Immune and inflammation
Source sentences
Summary
the in vitro assay showed that Tα1-iRGD presented a similar activity as Tα1 in promoting proliferation of mouse splenocytes.
2 context sentences(design, population, supporting numbers)
Summary · context
In this study, we explored whether the introduction of a permeability-enhancing sequence, such as iRGD (CRGDK/RGPD/EC) fragments, would enhance the activity of thymosin alpha 1 (Tα1).
Summary · context
The modified Tα1 (Tα1-iRGD) was successfully expressed and purified, and the in vitro assay showed that Tα1-iRGD presented a similar activity as Tα1 in promoting proliferation of mouse splenocytes.
In this study, Thymosin alpha-1 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 alpha-1.
Show in the study text Report a problemFND-2397726201
02LabNot a test of Thymosin alpha-1 aloneIn vitro (cells)Activity measurement
In cell adhesion assays, the Tα1-iRGD fusion bound tumor cells more specifically and more strongly than thymosin α1.
In plain wordsIn lab tests, the modified peptide stuck to tumor cells more strongly than thymosin α1.
Peptide
Thymosin alpha-1
Outcome
IncreaseBinding to tumor cells (cell adhesion)
Study
n: not reported in source
Comparator
Thymosin α1
Outcome group
Tumor growth · Cancer
Source sentences
Summary
Meanwhile, cell adhesion analysis revealed that Tα1-iRGD exhibited more specific and greater binding with tumor cells compared with Tα1.
2 context sentences(design, population, supporting numbers)
Summary · context
In this study, we explored whether the introduction of a permeability-enhancing sequence, such as iRGD (CRGDK/RGPD/EC) fragments, would enhance the activity of thymosin alpha 1 (Tα1).
Summary · context
The modified Tα1 (Tα1-iRGD) was successfully expressed and purified, and the in vitro assay showed that Tα1-iRGD presented a similar activity as Tα1 in promoting proliferation of mouse splenocytes.
In this study, Thymosin alpha-1 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 alpha-1.
Show in the study text Report a problemFND-2397726202
03LabNot a test of Thymosin alpha-1 aloneIn vitro (cells)Activity measurement
In mouse B16F10 melanoma cells, the Tα1-iRGD fusion inhibited proliferation more than thymosin α1.
In plain wordsIn lab tests on mouse melanoma cells, the modified peptide slowed cell growth more than thymosin α1.
Peptide
Thymosin alpha-1
Outcome
DecreaseInhibition of B16F10 melanoma cell proliferation
Study
mousen: not reported in source
B16F10 melanoma cell line
Comparator
Thymosin α1
Outcome group
Tumor growth · Cancer
Source sentences
Summary
Furthermore, the iRGD fragment evidently enhanced the basal ability of Tα1 to inhibit proliferation of cancer cells in vitro, particularly of mouse melanoma cell line B16F10 and human lung cancer cell line H460.
2 context sentences(design, population, supporting numbers)
Summary · context
In this study, we explored whether the introduction of a permeability-enhancing sequence, such as iRGD (CRGDK/RGPD/EC) fragments, would enhance the activity of thymosin alpha 1 (Tα1).
Summary · context
The modified Tα1 (Tα1-iRGD) was successfully expressed and purified, and the in vitro assay showed that Tα1-iRGD presented a similar activity as Tα1 in promoting proliferation of mouse splenocytes.
In this study, Thymosin alpha-1 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 alpha-1.
Show in the study text Report a problemFND-2397726203
04LabNot a test of Thymosin alpha-1 aloneIn vitro (cells)Activity measurement
In human H460 lung cancer cells, the Tα1-iRGD fusion inhibited proliferation more than thymosin α1.
In plain wordsIn lab tests on human lung cancer cells, the modified peptide slowed cell growth more than thymosin α1.
Peptide
Thymosin alpha-1
Outcome
DecreaseInhibition of H460 lung cancer cell proliferation
Study
humann: not reported in source
H460 lung cancer cell line
Comparator
Thymosin α1
Outcome group
Tumor growth · Cancer
Source sentences
Summary
Furthermore, the iRGD fragment evidently enhanced the basal ability of Tα1 to inhibit proliferation of cancer cells in vitro, particularly of mouse melanoma cell line B16F10 and human lung cancer cell line H460.
2 context sentences(design, population, supporting numbers)
Summary · context
In this study, we explored whether the introduction of a permeability-enhancing sequence, such as iRGD (CRGDK/RGPD/EC) fragments, would enhance the activity of thymosin alpha 1 (Tα1).
Summary · context
The modified Tα1 (Tα1-iRGD) was successfully expressed and purified, and the in vitro assay showed that Tα1-iRGD presented a similar activity as Tα1 in promoting proliferation of mouse splenocytes.
In this study, Thymosin alpha-1 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 alpha-1.
Show in the study text Report a problemFND-2397726204

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 3Current
10 Oct 2026, 08:55 UTC
Study results updated
Version 2
9 Oct 2026, 03:03 UTC
Study data updated · source update from Europe PMC
Version 1
9 Oct 2026, 03:02 UTC
First added · source update from Europe PMC

Subjects

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