Radiation-Induced Upregulation of Gene Expression From Adenoviral Vectors Mediated by DNA Damage Repair and Regulation

Cathepsin S (CTSS) has previously been implicated in a number of cancer types, where it is associated with poor clinical features and outcome. To date, patient outcome in breast cancer has not been examined with respect to this protease. Here, we carried out immunohistochemical (IHC) staining of CTSS using a breast cancer tissue microarray in patients who received adjuvant therapy. We scored CTSS expression in the epithelial and stromal compartments and evaluated the association of CTSS expression with matched clinical outcome data. We observed differences in outcome based on CTSS expression, with stromal-derived CTSS expression correlating with a poor outcome and epithelial CTSS expression associated with an improved outcome. Further subtype characterisation revealed high epithelial CTSS expression in TNBC patients with improved outcome, which remained consistent across two independent TMA cohorts. Furtherin silicogene expression analysis, using both in-house and publicly available datasets, confirmed these observations and suggested high CTSS expression may also be beneficial to outcome in ER-/HER2+ cancer. Furthermore, high CTSS expression was associated with the BL1 Lehmann subgroup, which is characterised by defects in DNA damage repair pathways and correlates with improved outcome. Finally, analysis of matching IHC analysis reveals an increased M1 (tumour destructive) polarisation in macrophage in patients exhibiting high epithelial CTSS expression. In conclusion, our observations suggest epithelial CTSS expression may be prognostic of improved outcome in TNBC. Improved outcome observed with HER2+ at the gene expression level furthermore suggests CTSS may be prognostic of improved outcome in ER- cancers as a whole. Lastly, from the context of these patients receiving adjuvant therapy and as a result of its association with BL1 subgroup CTSS may be elevated in patients with defects in DNA damage repair pathways, indicating it may be predictive of tumour sensitivity to DNA damaging agents.

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Changes in DNA Damage Repair Gene Expression and Cell Cycle Gene Expression Do Not Explain Radioresistance in Tamoxifen-Resistant Breast Cancer

Oncology Research Featuring Preclinical and Clinical Cancer Therapeutics ◽

10.3727/096504019x15555794826018 ◽

2020 ◽

Vol 28 (1) ◽

pp. 33-40 ◽

Cited By ~ 3

Author(s):

Annemarie E. M. Post ◽

Johan Bussink ◽

Fred C. G. J. Sweep ◽

Paul N. Span

Keyword(s):

Breast Cancer ◽

Gene Expression ◽

Cell Cycle ◽

Dna Damage ◽

Dna Damage Repair ◽

Cross Resistance ◽

Damage Repair ◽

Breast Cancer Cohort ◽

Tamoxifen Resistant ◽

Repair Genes

Tamoxifen-induced radioresistance, reported in vitro, might pose a problem for patients who receive neoadjuvant tamoxifen treatment and subsequently receive radiotherapy after surgery. Previous studies suggested that DNA damage repair or cell cycle genes are involved, and could therefore be targeted to preclude the occurrence of cross-resistance. We aimed to characterize the observed cross-resistance by investigating gene expression of DNA damage repair genes and cell cycle genes in estrogen receptor-positive MCF-7 breast cancer cells that were cultured to tamoxifen resistance. RNA sequencing was performed, and expression of genes characteristic for several DNA damage repair pathways was investigated, as well as expression of genes involved in different phases of the cell cycle. The association of differentially expressed genes with outcome after radiotherapy was assessed in silico in a large breast cancer cohort. None of the DNA damage repair pathways showed differential gene expression in tamoxifen-resistant cells compared to wild-type cells. Two DNA damage repair genes were more than two times upregulated (NEIL1 and EME2), and three DNA damage repair genes were more than two times downregulated (PCNA, BRIP1, and BARD1). However, these were not associated with outcome after radiotherapy in the TCGA breast cancer cohort. Genes involved in G1, G1/S, G2, and G2/M phases were lower expressed in tamoxifen-resistant cells compared to wild-type cells. Individual genes that were more than two times upregulated (MAPK13) or downregulated (E2F2, CKS2, GINS2, PCNA, MCM5, and EIF5A2) were not associated with response to radiotherapy in the patient cohort investigated. We assessed the expression of DNA damage repair genes and cell cycle genes in tamoxifen-resistant breast cancer cells. Though several genes in both pathways were differentially expressed, these could not explain the cross-resistance for irradiation in these cells, since no association to response to radiotherapy in the TCGA breast cancer cohort was found.

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Analysis of ionizing radiation-induced foci of DNA damage repair proteins

Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis ◽

10.1016/j.mrfmmm.2005.01.019 ◽

2005 ◽

Vol 574 (1-2) ◽

pp. 22-33 ◽

Cited By ~ 49

Author(s):

Lieneke R. van Veelen ◽

Tiziana Cervelli ◽

Mandy W.M.M. van de Rakt ◽

Arjan F. Theil ◽

Jeroen Essers ◽

...

Keyword(s):

Dna Damage ◽

Ionizing Radiation ◽

Dna Damage Repair ◽

Damage Repair ◽

Radiation Induced

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Tumor Cell–Accelerated Senescence Is Associated With DNA-PKcs Status and Telomere Dysfunction Induced by Radiation

Dose-Response ◽

10.1177/1559325818771527 ◽

2018 ◽

Vol 16 (2) ◽

pp. 155932581877152 ◽

Cited By ~ 3

Author(s):

Miaomiao Zhang ◽

Xiaopeng Guo ◽

Yue Gao ◽

Dong Lu ◽

Wenjian Li

Keyword(s):

Dna Damage ◽

Real Time ◽

Genome Instability ◽

Dna Damage Repair ◽

Cancer Cell Line ◽

Histochemical Staining ◽

Damage Repair ◽

Radiation Induced ◽

Accelerated Senescence ◽

Mcf 7

Whether telomere structure integrity is related to radiosensitivity is not well investigated thus far. In this study, we investigated the relation between telomere instability and radiation-induced accelerated senescence. Partial knockdown of DNA-dependent catalytic subunit of protein kinase (DNA-PKcs) in human breast cancer cell line MCF-7 was established by small interfering RNA. Radiosensitivity of control and DNA-PKcs knockdown MCF-7 cells was analyzed by clonogenetic assay. Cell growth was measured by real-time cell electronic sensing. Senescence and apoptosis were evaluated by β-galactosidase histochemical staining and fluorescence-activated cell sorting, respectively. DNA damage was determined by long polymerase chain reaction (PCR). Telomere length and integrity were analyzed by real-time PCR and cytogenetic assay, respectively. DNA-PKcs knockdown MCF-7 cells were more sensitive to X-irradiation than control cells. Further investigation revealed that accelerated senescence is more pronounced than apoptosis in cells after radiation, particularly in DNA-PKcs knockdown cells. The cytogenetic assay and kinetics of DNA damage repair revealed that the role of telomere end-capping in DNA-PKcs, rather than DNA damage repair, was more relevant to radiosensitivity. To our knowledge, this is the first study to show that DNA-PKcs plays an important role in radiation-induced accelerated senescence via maintenance of telomere integrity in MCF-7 cells. These results could be useful for future understanding of the radiation-induced genome instability and its consequences.

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Bortezomib Enhances Melphalan Response by Altering Fanconi Anemia (FA)/BRCA Pathway Expression and Function.

Blood ◽

10.1182/blood.v108.11.840.840 ◽

2006 ◽

Vol 108 (11) ◽

pp. 840-840 ◽

Cited By ~ 1

Author(s):

Danielle N. Yarde ◽

Lori A. Hazlehurst ◽

Vasco A. Oliveira ◽

Qing Chen ◽

William S. Dalton

Keyword(s):

Gene Expression ◽

Dna Damage ◽

Dna Repair ◽

Low Dose ◽

Dna Damage Repair ◽

Myeloma Cell ◽

Myeloma Cells ◽

Multiple Myeloma Cell ◽

Damage Repair ◽

Pre Treatment

Abstract The FA/BRCA pathway is involved in DNA damage repair and its importance in oncogenesis has only recently been implicated. Briefly, 8 FA/BRCA pathway family members facilitate the monoubiquitination of FANCD2. Upon monoubiquitination, FANCD2 translocates to the DNA repair foci where it interacts with other proteins to initiate DNA repair. Previously, we reported that the FA/BRCA pathway is upregulated in multiple myeloma cell lines selected for resistance to melphalan (Chen, et al, Blood 2005). Further, reducing FANCF in the melphalan resistant 8226/LR5 myeloma cell line partially reversed resistance, whereas overexpressing FANCF in the drug sensitive 8226/S myeloma line conferred resistance to melphalan. Others have reported, and we have also verified, that bortezomib enhances melphalan response in myeloma cells; however, the mechanism of enhanced melphalan activity in combination with bortezomib has not been reported. Based on our observation that the FA/BRCA pathway confers melphalan resistance, we hypothesized that bortezomib enhances melphalan response by targeting FA/BRCA DNA damage repair pathway genes. To investigate this hypothesis, we first analyzed FA/BRCA gene expression in 8226/S and 8226/LR5 cells treated with bortezomib, using a customized microfluidic card (to detect BRCA1, BRCA2, FANCA, FANCC, FANCD2, FANCE, FANCF, FANCG, FANCL, RAD51 and RAD51C) and q-PCR. Interestingly, we found that low dose (5nM) bortezomib decreased many FA/BRCA pathway genes as early as 2 hours, with maximal decreases seen at 24 hours. Specifically, 1.5- to 2.5-fold decreases in FANCA, FANCC, FANCD2, FANCE and RAD51C were seen 24 hours post bortezomib exposure. Moreover, pre-treatment of myeloma cells with low dose bortezomib followed by melphalan treatment revealed a greater than 2-fold reduction in FANCD2 gene expression levels. We also found that melphalan treatment alone enhanced FANCD2 protein expression and activation (monoubiquitination), whereas the combination treatment of bortezomib followed by melphalan decreased activation and overall expression of FANCD2 protein. Taken together, these results suggest that bortezomib enhances melphalan response in myeloma by targeting the FA/BRCA pathway. Further understanding of the role of the FA/BRCA pathway in determining melphalan response may allow for more customized and effective treatment of myeloma.

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