Middle East Journal of Cancer

Bromelain Enhances Radiosensitivity in HT-29 Colorectal Cancer Cells: Increased Chromosomal Damage and Reduced Clonogenic Survival

Articles in Press

Document Type : Original Article(s)

Authors

Mona Haddad Zahmatkesh 1, 2
Amir Shojaeefar 3
Hamid Saeidi Saedi 4

1 GI Cancer Screening and Prevention Research Center, Guilan University of Medical Sciences, Rasht, Iran

2 Department of Pharmaceutical Biotechnology and Nuclear Pharmacy, School of Pharmacy, Guilan University of Medical Sciences, Rasht, Iran

3 Student Research Committee, School of Pharmacy, Guilan University of Medical Sciences, Rasht, Iran

4 Department of Radiation Oncology, GI Cancer Screening and Prevention Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran

10.30476/mejc.2026.112900.2480
Abstract
Background: Bromelain, a proteolytic enzyme extracted from pineapple stems, has demonstrated anticancer activity in several experimental models. However, its radiosensitizing effect in colorectal cancer remains insufficiently understood. The present study aimed to investigate the radiosensitizing effect of bromelain in HT-29 human colorectal adenocarcinoma cells.
Method: In this in-vitro experimental study, HT-29 cells were pretreated with bromelain (70 μg/mL) for 3 h before exposure to 2 or 4 Gy X-ray irradiation. Radiosensitivity was evaluated using the cytokinesis-block micronucleus assay, clonogenic survival assay, and catalase (CAT) and superoxide dismutase (SOD) activities. Statistical analyses were performed using GraphPad Prism version 8.0, with one-way analysis of variance (ANOVA) followed by Tukey’s multiple comparison test; A P < 0.05 was considered to be statistically significant.
Results: Bromelain alone produced minimal effects. Bromelain pretreatment significantly increased micronucleus frequency from 39.22 ± 2.03 to 46.00 ± 2.00 after 2 Gy and from 43.11 ± 2.00 to 53.00 ± 1.00 after 4 Gy irradiation (P < 0.01). It also reduced clonogenic survival from 57.33 ± 2.04% to 49.00 ± 1.00% after 2 Gy and from 46.24 ± 1.67% to 29.10 ± 2.01% after 4 Gy (P < 0.001). Irradiation reduced CAT and SOD activities, whereas bromelain produced an additional significant decrease only in SOD activity.
Conclusion: Bromelain enhanced radiosensitivity in HT-29 cells by increasing radiation-induced chromosomal damage, reducing clonogenic survival, and further suppressing SOD activity. These findings support further investigation of bromelain as a naturally derived radiosensitizer for colorectal cancer.

Highlights

Mona Haddad Zahmatkesh (google scholar)

Keywords

Bromelain
Colorectal neoplasms
Radiosensitization
Micronucleus assay
Clonogenic survival
Subjects

Please cite this article as:

 Haddad Zahmatkesh M, Shojaeefar A, Saeidi Saedi H. Bromelain enhances radiosensitivity in HT-29 colorectal cancer cells: Increased chromosomal damage and reduced clonogenic survival. Middle East J Cancer. 2026: in press. doi: 10.30476/mejc.2026.112900.2480.

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Middle East Journal of Cancer

Articles in Press, Accepted Manuscript
Available Online from 01 July 2027

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