Expression of proapoptotic BAX and TP53 genes and antiapoptotic BCL-2 gene in MCF-7 and T-47D tumour cell cultures of the mammary gland after a photodynamic therapy with photolon.

Abstract

BACKGROUND:

Breast cancer is the most common malignant tumour in women in the whole world. Despite significant developments in the early diagnosis of breast cancer, there is no effective method which would assure total recovery of the patient. Currently available clinical data and laboratory tests indicate a possibility to introduce photodynamic therapy (PDT) to the supplementary treatment of breast cancer.

OBJECTIVES:

The aim of this study was to assess the influence of PDT with Photolon as a photosensibilizator on the expression of apoptosis associated genes (BCL-2, BAX, TP53) in human breast cancer cell lines, preceded by assessment of survivorship and proliferative activity in the tested cells after PDT.

MATERIAL AND METHODS:

In the present study human breast cancer cell lines MCF-7 and T-47D were used. Photolon (chlorin e6 complex: PVP 1:1) was used as a photosensitizer. Assessments of survivorship and proliferative activity of cells under the influence of PDT (WST-1 test) were conducted along with the expression of selected genes involved in the process of apoptosis: BCL-2, BAX, TP53 (RT-QPCR).

RESULTS:

PDT limited both survivorship and proliferative activity of breast cancer cells in the two tested lines. In case of T-47D cell line was found increase of BAX and BCL-2 genes expression after PDT and sustained activity of TP53 gene. Conversely, in MCF-7 cell line a decrease in expression was found for both BAX and TP53 genes, but also an increase of BCL-2 gene expression.

CONCLUSIONS:

A progressing decrease (24, 48 and 72 h after PDT) in the count of culture cells, which suggests the occurrence of apoptosis initiated by a photodynamic reaction with simultaneous increase of BCL-2/BAX index, indicates activation of a different endogenous apoptosis pathway than the one examined, namely pointing to suicidal death of cells after PDT.

• Authors: Justyna Płonka, Małgorzata Latocha, Dariusz Kuśmierz, Aleksandra Zielińska
• Journal: Advances in clinical and experimental medicine : official organ Wroclaw Medical University (Adv Clin Exp Med) 2015 Jan-Feb Vol. 24 Issue 1 Pg. 37-46 ISSN: 1899-5276 [Print] Poland
• PMID: 25923085 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• BCL2 protein, human
• Chlorophyllides
• Photosensitizing Agents
• Porphyrins
• Proto-Oncogene Proteins c-bcl-2
• Protoporphyrins
• RNA, Messenger
• TP53 protein, human
• Tumor Suppressor Protein p53
• bcl-2-Associated X Protein
• phytochlorin
• Povidone

Topics

• Apoptosis (drug effects, radiation effects)
• Cell Line, Tumor
• Cell Proliferation (drug effects, radiation effects)
• Cell Survival (drug effects, radiation effects)
• Chlorophyllides
• Female
• Gene Expression Regulation, Neoplastic
• Humans
• Light
• MCF-7 Cells
• Mammary Glands, Human (drug effects, metabolism, pathology, radiation effects)
• Photochemotherapy
• Photosensitizing Agents (pharmacology)
• Porphyrins
• Povidone (pharmacology)
• Proto-Oncogene Proteins c-bcl-2 (genetics, metabolism)
• Protoporphyrins (pharmacology)
• RNA, Messenger (genetics, metabolism)
• Signal Transduction
• Tumor Suppressor Protein p53 (genetics, metabolism)
• bcl-2-Associated X Protein (genetics, metabolism)