Impact of background music listening on anxiety in cancer patients undergoing initial radiation therapy: a randomized clinical trial.

BACKGROUND: Patients undergoing radiation therapy (RT) often experience anxiety, which may jeopardize the treatment success. The efficacy of music interventions in reducing anxiety remains contentious. This randomized trial aimed to evaluate the impact of music listening on anxiety symptoms in patients undergoing initial RT. METHODS: First-time RT patients were randomly allocated to experimental and control groups. The Brief Symptom Rating Scale (BSRS-5), Distress Thermometer (DT), and Beck Anxiety Inventory (BAI-C) were administered pre- and post-RT. Changes in physiological anxiety symptoms were monitored over 10 consecutive days starting from the first day of RT. The experimental group received music during RT; the control group did not. The generalized linear mixed model was used to estimate the pre-post difference in the BSRS-5, DT, and BAI-C scores between the music intervention and control group. RESULTS: This study included 50 patients each in the experimental and control groups. BSRS-5 and DT scores were significantly reduced in the experimental group post-RT (p = 0.0114 and p = 0.0023, respectively). When music listening was discontinued, these scores rebounded. While the posttest BAI-C score was significantly lower in the experimental group (p < 0.0001), the pre-post difference between the two groups was not significant (p = 0.0619). On cessation of music listening, the BAI-C score also rebounded. CONCLUSIONS: For cancer patients undergoing initial RT, music listening intervention significantly reduced anxiety symptoms measured using the BSRS-5, DT, and BAI-C scores after two weeks. Our results demonstrate the effectiveness of music listening intervention in reducing anxiety symptoms, thereby potentially improving the quality of life of cancer patients undergoing RT.

CSMed® wound dressing for prophylaxis and management of radiation dermatitis in breast and head-neck cancer patients: a single hospital prospective clinical trial.

PURPOSE: CSMed® wound dressing, a dressing with various herb extracts, was tested for its therapeutic effect in radiation dermatitis of breast and head-and-neck cancer patients. METHODS: This study included 20 breast cancer patients and 10 head-and-neck cancer patients. Half of the irradiated area was covered with CSMed® and the other half was under routine treatment. The severity of radiation dermatitis was evaluated with radiation therapy oncology group (RTOG) grade throughout the treatment and the follow-up period. The RTOG grade between the dressed and undressed area were compared to illustrate the therapeutic effect of CSMed® dressing. RESULTS: The results showed that CSMed® dressed area had significant lower RTOG score at 3-7 weeks and final record during the treatment, and 1-3 weeks during follow-up than undressed area. CONCLUSIONS: This indicated that CSMed® can delay the onset, reduce the severity, and enhance healing of radiation dermatitis. CSMed® can be used for prophylaxis and management of radiation dermatitis.

Exon Junction Complex Mediates the Cap-Independent Translation of Circular RNA.

Evidence that circular RNAs (circRNA) serve as protein template is accumulating. However, how the cap-independent translation is controlled remains largely uncharacterized. Here, we show that the presence of intron and thus splicing promote cap-independent translation. By acquiring the exon junction complex (EJC) after splicing, the interaction between circRNA and ribosomes was promoted, thereby facilitating translation. Prevention of splicing by treatment with spliceosome inhibitor or mutating splicing signal hindered cap-independent translation of circRNA. Moreover, EJC-tethering using Cas13 technology reconstituted EJC-dependent circRNA translation. Finally, the level of a coding circRNA from succinate dehydrogenase assembly factor 2 (circSDHAF2) was found to be elevated in the tumorous tissues from patients with colorectal cancer, and shown to be critical in tumorigenesis of colorectal cancer in both cell and murine models. These findings reveal that EJC-dependent control of circSDHAF2 translation is involved in the regulation of oncogenic pathways. IMPLICATIONS: EJC-mediated cap-independent translation of circRNA is implicated in the tumorigenesis of colorectal cancer.

Effectiveness of multimedia courses in improving self-care among patients with breast cancer undergoing radiotherapy.

BACKGROUND: Ninety percent of patients receiving radiation therapy experience side effects. Busy schedules and intensive health education programs may lead to incomplete education content delivery and inaccurate patient self-care implementation. This study investigated whether multimedia health education improves the accuracy of patient self-care implementation compared with paper-based education. METHODS: From March 11, 2020 to February 28, 2021, 110 patients were randomly divided into experimental and control groups, each comprising 55 participants. Paper-based materials were used along with multimedia materials. Radiology self-care awareness questionnaires were administered to both groups before the first treatment and on day 10. The differences in radiology self-care awareness between the two groups was analyzed with inferential statistics, independent t tests, categorical data, and Pearson's chi-squared test. Differences between the two groups were considered significant at a p value of < 0.05. RESULTS: The treatment accuracy rate improved from 10.9 to 79.1% in the control group and from 24.8 to 98.5% in the experimental group, indicating an improvement in both groups. The difference was significant. These results indicate that the intervention could improve the effectiveness of self-care. CONCLUSIONS: Participants who used pretreatment multimedia health education exhibited a higher rate of having a correct understanding of treatment self-care than did the control group. These findings can inform the development of a patient-centered cancer treatment knowledge base for improved quality of care.

A Novel 3D Culture Scaffold to Shorten Development Time for Multicellular Tumor Spheroids.

Multicellular tumor spheroids and tumoroids are considered ideal in vitro models that reflect the features of the tumor microenvironment. Biomimetic components resembling the extracellular matrix form scaffolds to provide structure to 3-dimensional (3D) culture systems, supporting the growth of both spheroids and tumoroids. Although Matrigel has long been used to support 3D culture systems, batch variations, component complexity, and the use of components derived from tumors are complicating factors. To address these issues, we developed the ACD 3D culture system to provide better control and consistency. We evaluated spheroid and tumoroid formation using the ACD 3D culture system, including the assessment of cell viability and cancer marker expression. Under ACD 3D culture conditions, spheroids derived from cancer cell lines exhibited cancer stem cell characteristics, including a sphere-forming size and the expression of stem cell marker genes. The ACD 3D culture system was also able to support patient-derived primary cells and organoid cell cultures, displaying adequate cell growth, appropriate morphology, and resistance to oxaliplatin treatment. These spheroids could also be used for drug screening purposes. In conclusion, the ACD 3D culture system represents an efficient tool for basic cancer research and therapeutic development.

The Functional Roles and Regulation of Circular RNAs during Cellular Stresses.

Circular RNAs (circRNAs) are a novel class of regulatory RNA involved in many biological, physiological and pathological processes by functioning as a molecular sponge, transcriptional/epigenetic/splicing regulator, modulator of protein-protein interactions, and a template for encoding proteins. Cells are constantly dealing with stimuli from the microenvironment, and proper responses rely on both the precise control of gene expression networks and protein-protein interactions at the molecular level. The critical roles of circRNAs in the regulation of these processes have been heavily studied in the past decades. However, how the microenvironmental stimulation controls the circRNA biogenesis, cellular shuttling, translation efficiency and degradation globally and/or individually remains largely uncharacterized. In this review, how the impact of major microenvironmental stresses on the known transcription factors, splicing modulators and epitranscriptomic regulators, and thereby how they may contribute to the regulation of circRNAs, is discussed. These lines of evidence will provide new insight into how the biogenesis and functions of circRNA can be precisely controlled and targeted for treating human diseases.

CircVIS: a platform for circRNA visual presentation.

BACKGROUND: The collection of circRNAs mostly focused on their sequence composition such as protein/miRNA binding motif, and/or regulatory elements such as internal ribosome entry site. However, less attention was paid to subcellular localization. CircVIS aimed to provide a collection of circRNAs with information of subcellular compartments and also integrated the circRNA entries from previous circRNA databases. RESULTS: A collection of circRNAs from public circRNA databases and de novo identification were annotated according to subcellular localizations including nucleoplasm, chromatin-associated parts, cytoplasm and polyribosome. All circRNAs were aligned to a selected major transcript, and if presence, the circRNA-derived open reading frame with annotation of functional domain were compared to its parental protein. The results showed that distinct circRNAs may exert their molecular and cellular functions in different subcellular compartments. The web service is made freely available at http://lab-x-omics.nchu.edu.tw/circVIS . CONCLUSIONS: CircVIS allows users to visualize the alignment between a given circRNA and its most relevant reference transcript along with information of subcellular localization.

Tribbles Pseudokinase 3 Contributes to Cancer Stemness of Endometrial Cancer Cells by Regulating ß-Catenin Expression.

Endometrial cancer (EC) is the second most common gynecological malignancy worldwide. Tribbles pseudokinase 3 (TRIB3) is a scaffolding protein that regulates intracellular signal transduction, and its role in tumor development is controversial. Here, we investigated the biological function of TRIB3 in EC. We found that the messenger RNA (mRNA) expression level of TRIB3 was significantly and positively correlated with shorter overall survival of EC patients in The Cancer Genome Atlas database. The protein expression of TRIB3 was found to be significantly increased in EC cancer stem cells (CSCs) enriched by tumorsphere cultivation. Knockdown of TRIB3 in EC cells suppressed tumorsphere formation, the expression of cancer stemness genes, and the in vivo tumorigenesis. The expression of ß-catenin at both the protein and the mRNA levels was downregulated upon TRIB3 silencing. TRIB3 was found to interact with E74 Like ETS transcription factor 4 (ELF4) in the nucleus and bound to ELF4 consensus sites within the catenin beta 1 (CTNNB1) promoter in EC cell lines. These data indicated that TRIB3 may regulate CTNNB1 transcription by enhancing the recruitment of ELF4 to the CTNNB1 promoter. In conclusion, our results suggest that TRIB3 plays an oncogenic role in EC and positively regulates the self-renewal and tumorigenicity of EC-CSCs. Targeting TRIB3 is considered as a potential therapeutic strategy in future EC therapy.

NAD(P)H:quinone oxidoreductase 1 determines radiosensitivity of triple negative breast cancer cells and is controlled by long non-coding RNA NEAT1.

Radioresistant cells cause recurrence in patients with breast cancer after they undergo radiation therapy. The molecular mechanisms by which cancer cells obtain radioresistance should be understood to develop radiation-sensitizing agents. Results showed that the protein expression and activity of NAD(P)H:quinone oxidoreductase 1 (NQO1) were upregulated in radioresistant MDA-MB-231 triple-negative breast cancer (TNBC) cells. NQO1 knockdown inhibited the proliferation of NQO1 expressing Hs578t TNBC cells or the radioresistant MDA-MB-231 cells, whereas NOQ1 overexpression increased the survival of MDA-MB-231 cells, which lack of NQO1 expression originally, under irradiation. The cytotoxicity of ß-lapachone, an NQO1-dependent bioactivatable compound, was greater in radioresistant MDA-MB-231 cells than in parental cells. ß-lapachone displayed a radiosensitization effect on Hs578t or radioresistant MBDA-MB-231 cells. The expression of the long noncoding RNA NEAT1 positively regulated the NQO1 expression in radioresistant MDA-MB-231 cells at a translational level rather than at a transcription level. The inhibition of the NEAT1 expression through the CRISPR-Cas9 method increased the sensitivity of radioresistant MDA-MB-231 cells to radiation and decreased their proliferation, the activity of cancer stem cells, and the expression of stemness genes, including BMI1, Oct4, and Sox2. In conclusion, the NQO1 expression in triple-negative breast cancer cells determined their radiosensitivity and was controlled by NEAT1. In addition, NOQ1 bioactivatable compounds displayed potential for application in the development of radiation sensitizers in breast cancer.

The relationships of genetic polymorphisms of the long noncoding RNA growth arrest-specific transcript 5 with uterine cervical cancer.

The purposes of the investigation were to examine the implications of long noncoding RNA growth arrest-specific transcript 5 (GAS5) in progression and clinicopathological factors of uterine cervical cancer, and patient survival in Taiwan. Genotypic distributions of two GAS5 genetic variants rs145204276 and rs55829688 were detected in 208 patients including 111 patients with invasive cancer, 97 with precancerous lesions as well as 307 control women using real-time polymerase chain reaction. It explored that patients with cervical precancerous lesion had lower rate of AGGCA deletion (Del) in both alleles (Del/Del) of GAS5 rs145204276 as compared with control women. Patients with invasive cancer did not exhibit higher rate of Del/Del. Meanwhile, there were no different genotypic distributions in rs55829688 among patients with cervical invasive cancer and those with precancerous lesions as well as control women. Moreover, cervical cancer patients with Ins (insertion, AGGCA)/Del and Del/Del (-/-) in GAS5 rs55829688 tended to have poorer hazard ratio (HR) of 5 years survival. In addition, lymph node metastasis status exerted the most significantly predictive of 5 years survival rate. Conclusively, GAS5 polymorphism rs145204276 is probably applicable to predict 5 years survival HR of cervical cancer patients. However, the mechanism elucidating the methylation status and transcription function of rs145204276 in uterine cervical cancer needs to be delineated for its unique implication in uterine cervical cancer.

Reciprocal Regulation Between Indoleamine 2,3-Dioxigenase 1 and Notch1 Involved in Radiation Response of Cervical Cancer Stem Cells.

Cervical cancer is the fourth most common cancer in women around the world. Cancer stem cells (CSCs) are responsible for cancer initiation, as well as resistance to radiation therapy, and are considered as the effective target of cancer therapy. Indoleamine 2,3-dioxygenase 1 (IDO1) mediates tryptophan metabolism and T cell suppression, but the immune-independent function of IDO1 in cancer behavior is not fully understood. Using tumorsphere cultivation for enriched CSCs, we firstly found that IDO1 was increased in HeLa and SiHa cervical cancer cells and in these two cell lines after radiation treatment. The radiosensitivity of HeLa and SiHa tumorsphere cells was increased after the inhibition of IDO1 through RNA interference or by the treatment of INCB-024360, an IDO1 inhibitor. With the treatment of kynurenine, the first breakdown product of the IDO1-mediated tryptophan metabolism, the radiosensitivity of HeLa and SiHa cells decreased. The inhibition of Notch1 by shRNA downregulated IDO1 expression in cervical CSCs and the binding of the intracellular domain of Notch (NICD) on the IDO1 promoter was reduced by Ro-4929097, a γ-secretase inhibitor. Moreover, the knockdown of IDO1 also decreased NICD expression in cervical CSCs, which was correlated with the reduced binding of aryl hydrocarbon receptor nuclear translocator to Notch1 promoter. In vivo treatment of INCB-0234360 sensitized SiHa xenograft tumors to radiation treatment in nude mice through increased DNA damage. Furthermore, kynurenine increased the tumorsphere formation capability and the expression of cancer stemness genes including Oct4 and Sox2. Our data provide a reciprocal regulation mechanism between IDO1 and Notch1 expression in cervical cancer cells and suggest that the IDO1 inhibitors may potentially be used as radiosensitizers.

TLD environmental monitoring of new scanner facilities at the Nuclear Medicine Department of the Taiwan Medical University Hospital.

OBJECTIVE: Single-photon emission computed tomography (SPECT) as well as dual energy X-ray absorptiometry (DXA) scanners were designed in July 2018 at the Nuclear Medicine Department (NM), of the Taiwan Medical University Hospital. These scanners emit substantial X-rays from the target, which are tungsten, iron. Therefore, patients undergoing SPECT and DXA diagnosis, in addition to medical personnel, are exposed to undesirable photon leakage. METHODS: Following administration of radiopharmaceuticals, patients become radioactive sources; thus, it is necessary to evaluate a possible increase in the environmental gamma exposure rates in the NM as a result of the operation of the new scanners. A three month evaluation of environmental radiation in the NM was performed using the accurate and sensitive TLD-100H approach, which gives an error rate less than 10%. RESULTS: Detected exposure radiation rates in the NM ranged from 0.12 ± 0.02 to 1.00 ± 0.15 mSv per month, indicating that the imaging room had significantly different radiation rates. The results were compared with previous results, and no significant contribution to the enhancement of environmental gamma radiation was detected, which remained far below the occupational dose recommended by ICRP 60. The minimum detectable dose (MDD) for environmental radiation is also discussed herein to demonstrate the reliability of TLD-100H. CONCLUSION: Recommendations were sent to the authorities of AEC-ROC to implement actions that could reduce doses at these high-dose locations to meet the ALARA principle.

Investigation of metastasis-associated in colon cancer-1 genetic variants in the development and clinicopathologcial characteristics of uterine cervical cancer in Taiwanese women.

The objectives of this study were to define the associations among single nucleotide polymorphisms (SNPs) of metastasis-associated in colon cancer-1 (MACC1) gene, development and clinicopathological characteristics of uterine cervical cancer, and patient survival in Taiwan. Genotypic frequencies of 5 MACC1 SNPs rs975263, rs3095007, rs4721888, rs3735615 and rs1990172 were identified for 132 patients with invasive cancer, 99 with high-grade cervical intraepithelial neoplasia and 338 normal controls using real-time polymerase chain reaction. It revealed that there were no associations of these MACC1 SNPs with cervical carcinogenesis. In the meantime, cervical cancer patients with genotype GG in MACC1 SNP rs975263 tended to display more risk to have vaginal invasion than those with AA/AG (p=0.042, OR: 8.70, 95% CI: 0.81-433.22). In multivariate analysis, positive pelvic lymph node metastasis could significantly predict worse 5 years survival rate (p=0.001; HR=9.98, 95% CI=2.64-37.77) for cervical cancer patients. In conclusion, pelvic lymph node status rather than MACC1 SNPs was the only independent parameter that could significantly predict 5 years survival rate in Taiwanese women with cervical cancer.

Glucose Transporter 3 is Essential for the Survival of Breast Cancer Cells in the Brain.

Breast cancer brain metastasis commonly occurs in one-fourth of breast cancer patients and is associated with poor prognosis. Abnormal glucose metabolism is found to promote cancer metastasis. Moreover, the tumor microenvironment is crucial and plays an active role in the metabolic adaptations and survival of cancer cells. Glucose transporters are overexpressed in cancer cells to increase glucose uptake. The glucose transporter 3 (GLUT3) is a high-affinity glucose transporter that is highly expressed in mammalian neurons. GLUT3 is also overexpressed in several malignant brain tumors. However, the role of GLUT3 in breast cancer brain metastasis remains unknown. The results of the present study demonstrated that GLUT3 is highly overexpressed in brain metastatic breast cancers and mediates glucose metabolic reprogramming. Furthermore, knockdown of cAMP-response element binding protein (CREB) could directly regulate GLUT3 expression in brain metastatic breast cancer cells. Notably, we verified and provided a novel role of GLUT3 in mediating glucose metabolism and assisting breast cancer cells to survive in the brain to promote brain metastasis.

The clinicopathological characteristic associations of long non-coding RNA gene H19 polymorphisms with uterine cervical cancer.

The purposes of the current study were conducted to explore the relationships among long non-coding RNA gene H19 (LncRNA H19) polymorphisms and clinicopathological characteristics of uterine cervical cancer, and patient prognosis in Taiwan. Five genetic variants of LncRNA H19 rs3024270, rs2839698, rs3741219, rs2107425 and rs217727 were recruited from one hundred and thirty-four patients with invasive cancer, 101 with high-grade cervical intraepithelial neoplasia (CIN) of uterine cervix and 325 controls and their genetic distributions were determined. It indicated no associations of these LncRNA H19 genetic variants with development of cervical cancer. CC/CT in LncRNA H19 rs2839698 exhibited less risk to have pelvic lymph node metastasis [Odds ratio (OR): 0.19, 95% Confidence interval (CI):0.04-0.82, p=0.028)], as compared with TT. Meanwhile, cervical cancer patients with AA/AG in rs3741219 also had less risk to develop pelvic lymph node metastasis (OR: 0.17, 95% CI: 0.05-0.63, p=0.008), large tumor (OR: 0.17, 95% CI: 0.04-0.82, p=0.014) as well as parametrium (OR: 0.26, 95% CI: 0.07-0.95, p=0.045) and vagina invasion (OR: 0.25, 95% CI: 0.07-0.91, p=0.041, as compared to those with GG. However, only positive pelvic lymph node metastasis was related to worse recurrence-free survival and poor overall survival. Conclusively, it indicated no association of LncRNA H19 SNPs with cervical carcinogensis in Taiwanese women. Although genotypes TT in LncRNA H19 rs2839698 and GG in rs3741219 are related to some poor clinicopathological parameters of cervical cancer, only pelvic lymph node status could predict 5 year patient survival significantly.

Analysis of common targets for circular RNAs.

BACKGROUND: The studies of functions of circular RNAs (circRNAs) are heavily focused on the regulation of gene expression through interactions with multiple miRNAs. However, the number of predicted target genes is typically overwhelming due to the synergistic complexity caused by two factors ─ the binding of multiple miRNAs to a circRNA and the existence of multiple targets for each miRNA. Analysis of common targets (ACT) was designed to facilitate the identification of potential circRNA targets. RESULTS: We demonstrated the feasibility of the proposed feature/measurement to assess which genes are more likely to be regulated by circRNAs with given sequences by calculating the level of co-regulation by multiple miRNAs. The web service is made freely available at http://lab-x-omics.nchu.edu.tw/ACT_Server . CONCLUSIONS: ACT allows users to identify potential circRNA-regulated genes and their associated pathways for further investigation.

Involvement of endothelial nitric oxide synthase gene variants in the aggressiveness of uterine cervical cancer.

To date, few studies explore the involvement of endothelial nitric oxide synthase (eNOS) gene variants in uterine cervical cancer. Therefore, we conducted this study to assess the clinical implication of eNOS in cervical carcinogenesis, clinicopathological characteristics and patient survival. One hundred and seventeen patients with cervical invasive cancer and 95 with preinvasive lesions and 330 control women were consecutively enrolled. Real time polymerase chain reaction was used to examine the genotypic distributions of eNOS single nucleotide polymorphisms (SNPs) rs1799983 (894G>T) at the exon 7 region and rs2070744 (-786T>C) at the promoter region. Our results indicated no significant associations among genotypic distributions of eNOS SNPs and patients with cervical invasive cancer and those with preinvasive lesions as well as normal controls. However, cervical cancer patients with genotypes TC/CC in eNOS SNP rs2070744 carried less risk of advanced stage [odds ratios (OR) = 0.30, 95% confidence interval (CI)=0.09-0.97, p=0.036], parametrium invasion (OR=0.16, 95% CI=0.02-0.75, p=0.009) and pelvic lymph node metastasis (OR=0.12, 95% CI=0.01-0.89, p=0.016). In conclusion, although eNOS SNPs rs2070744 and rs1799983 do not display significant associations with cervical carcinogenesis and patient survival, cervical cancer patients with genotypes TC/CC in rs2070744 carry less risk of advanced stage, parametrium invasion and pelvic lymph node metastasis in Taiwan.

Impact of matrix metalloproteinase-11 gene polymorphisms on development and clinicopathologcial variables of uterine cervical cancer in Taiwanese women.

The purposes of this study were to examine whether there were associations among matrix metalloproteinase-11 (MMP-11) gene polymorphisms, development and clinicopathological characteristics of uterine cervical cancer as well as patient survival or not. Five single-nucleotide polymorphisms (SNPs) of the MMP-11 gene rs738791, rs738792, rs2267029, rs28382575, and rs131451 from one hundred and thirty patients with invasive cancer, 99 patients with high-grade cervical intraepithelial neoplasia (CIN) of uterine and 335 normal controls were analyzed using real-time polymerase chain reaction. Our results revealed that genotypic frequencies of CT/TT in MMP-11 SNP rs738791, with CC as a reference, tended to exhibit significantly different distributions (p=0.044, AOR: 0.63, 95% CI: 0.41-0.99) between patients with cervical invasive cancer and normal control women when controlling age. After multiple significance adjustment, the tendency becomes insignificant (Holm's adjusted p 0.176). Although CT/TT genotype of MMP-11 gene rs738791 tended to increase the risk of developing stage II disease at least (p=0.035; OR: 2.16, 95% CI: 1.05-4.44) and deep stromal invasion more than 10 mm (p=0.043; OR: 2.08, 95% CI: 1.02-4.26) with CC as a reference in patients with uterine cervical cancer. They became insignificant after multiple significance adjustment and the Holm's adjusted p values would become as 0.245 and 0.258, respectively. However, lymph node metastasis exhibited significant worse recurrence-free survival (p=0.033; HR: 2.83, 95% CI: 1.09-7.35), and overall survival (p=0.001; HR: 4.80, 95% CI: 1.82-12.62) compared to those without pelvic lymph node metastasis. In conclusion, it indicates no impact of the MMP-11 SNPs on uterine cervical cancer in Taiwanese women.

Tribbles Homolog 3 Involved in Radiation Response of Triple Negative Breast Cancer Cells by Regulating Notch1 Activation.

Breast cancer is the most common cancer for women in Taiwan and post-lumpectomy radiotherapy is one of the therapeutic strategies for this malignancy. Although the 10-year overall survival of breast cancer patients is greatly improved by radiotherapy, the locoregional recurrence is around 10% and triple negative breast cancers (TNBCs) are at a high risk for relapse. The aim of this paper is to understand the mechanisms of radioresistance in breast cancers which may facilitate the development of new treatments in sensitizing breast cancer toward radiation therapy. Tribbles homolog 3 (TRIB3) is a pseudokinase protein and known to function as a protein scaffold within cells. It has been reported that higher TRIB3 expression is a poor prognostic factor in breast cancer patients with radiotherapy. In this study, we investigate the involvement of TRIB3 in the radiation response of TNBC cells. We first found that the expression of TRIB3 and the activation of Notch1, as well as Notch1 target genes, increased in two radioresistant TNBC cells. Knockdown of TRIB3 in radioresistant MDA-MB-231 TNBC cells decreased Notch1 activation, as well as the CD24-CD44⁺ cancer stem cell population, and sensitized cells toward radiation treatment. The inhibitory effects of TRIB3 knockdown in self-renewal or radioresistance could be reversed by forced expression of the Notch intracellular domain. We also observed an inhibition in cell growth and accumulated cells in the G0/G¹ phase in radioresistant MDA-MB-231 cells after knockdown of TRIB3. With immunoprecipitation and mass spectrometry analysis, we found that, BCL2-associated transcription factor 1 (BCLAF1), BCL2 interacting protein 1 (BNIP1), or DEAD-box helicase 5 (DDX5) were the possible TRIB3 interacting proteins and immunoprecipitation data also confirmed that these proteins interacted with TRIB3 in radioresistant MDA-MB-231 cells. In conclusion, the expression of TRIB3 in radioresistant TNBC cells participated in Notch1 activation and targeted TRIB3 expression may be a strategy to sensitize TNBC cells toward radiation therapy.