Radioresistant Patients Research Articles

Prognostic value of different radiation-related cell death genes in patients with lung adenocarcinoma

Background and aimsRadiotherapy is widely applied for lung adenocarcinoma (LUAD), while individualized differences led to different outcomes. This study aimed to establish a multi-gene risk scoring model to predict the benefits of LUAD patients from radiotherapy, based on different types of cell death respectively. ResultsOther than autophagy, pyroptosis, ferroptosis and Immunogenic cell death (ICD), the LUAD prognostic model based on apoptosis had the best performance, and the area under curves (AUCs) of the receiver operating curve (ROC) for 1-, 3-, and 5-year OS were 0.700,0.736,0.723,respectively. Such genes were involved as SLC7A5, EXO1, ABAT, NLRP1 and GAR1. Then patients were divided into high and low risk groups by the median apoptosis-LUAD risk score. For patients in the high-risk group, i.e., the radiotherapy-tolerant group, we screened adjuvant chemotherapy and found that besides the conventional first-line chemotherapy regimen, drugs such as Fludarabine, Pevonedistat, and Podophyllotoxin Bromide may also have potential therapeutic value. ConclusionThe multi-gene risk scoring model based on apoptosis might predict the radiotherapy benefits of LUAD patients and for those radioresistant patients classified by the model we also provided effective adjuvant chemicals, which would be used to guide clinical treatment.

Disulfiram: A novel repurposed drug for cancer therapy.

Cancer is a major global health issue. Effective therapeutic strategies can prolong patients' survival and reduce the costs of treatment. Drug repurposing, which identifies new therapeutic uses for approved drugs, is a promising approach with the advantages of reducing research costs, shortening development time, and increasing efficiency and safety. Disulfiram (DSF), a Food and Drug Administration (FDA)-approved drug used to treat chronic alcoholism, has a great potential as an anticancer drug by targeting diverse human malignancies. Several studies show the antitumor effects of DSF, particularly the combination of DSF and copper (DSF/Cu), on a wide range of cancers such as glioblastoma (GBM), breast cancer, liver cancer, pancreatic cancer, and melanoma. In this review, we summarize the antitumor mechanisms of DSF/Cu, including induction of intracellular reactive oxygen species (ROS) and various cell death signaling pathways, and inhibition of proteasome activity, as well as inhibition of nuclear factor-kappa B (NF-κB) signaling. Furthermore, we highlight the ability of DSF/Cu to target cancer stem cells (CSCs), which provides a new approach to prevent tumor recurrence and metastasis. Strikingly, DSF/Cu inhibits several molecular targets associated with drug resistance, and therefore it is becoming a novel option to increase the sensitivity of chemo-resistant and radio-resistant patients. Studies of DSF/Cu may shed light on its improved application to clinical tumor treatment.

Targeting XPO1 Combined with Radiotherapy to Enhance Systemic Anti-tumor Effects in Non-Small Cell Lung Cancer

The combination of radiation and radiosensitizing chemotherapeutic agents have shown promising anti-tumor effects in NSCLC. Acting as an oncogenic driver, XPO1 is frequently overexpressed and/or mutated in lung cancer. Thus, suppression of XPO1-mediated nuclear export presents a unique therapeutic strategy. We hypothesize that XPO1 inhibition combined with radiotherapy (XRT) may remodel the tumor immune microenvironment (TIME) and reduce radioresistance, thus enhance systemic anti-tumor effects. Herein, we optimized a small molecule inhibitor, WJ01024, which can bind to XPO1 and antagonize its activity to inhibit nuclear export. In the C57BL/6 mouse subcutaneous tumor model, we evaluated the ability of different treatment regimens containing oral WJ01014 single or combined with XRT (one fractions of 15 Gy) in tumor control and tumor recurrence inhibition. The effects of each treatment regimen on the alterations of immunophenotypes, including the quantification, activation, proliferative capacity, exhaustion marker expression, and memory status, were evaluated by flow cytometry. In our study, we found that the overexpression of XPO1 was associated with poor prognosis and survival in radioresistant patients with NSCLC. The combination therapy of WJ01024 and XRT resulted in an increase of apoptosis and a decrease of proliferation compared to monotherapy, which was closely correlated with tumor regression and improved survival in the C57BL/6 mouse subcutaneous tumor model. Notably, we found that WJ01024 were shown to enhance the therapeutic effect of XRT by remodeling TIME. Compared with XRT, the addition of WJ01024 increased the infiltration and proliferation of radiation-stimulated CD8+ T cells, which especially promoted the production of interferon-γ and granzyme B. Moreover, the combination therapy also reversed the immunosuppressive effect of radiation on the percentage of Tregs and exhausted T cells in mouse xenografts. Thus, the TIME was significantly improved in combination therapy. Strikingly, mechanistic studies suggested that the activation of cyclic GMP-AMP synthase/stimulator of interferon genes (cGAS/STING) signaling pathway is required to reshape TIME and produce synergistic anti-tumor effect with the combination of WJ01024 and XRT. Our findings suggest that WJ01024 might be a potential synergistic treatment for radiotherapy to control the proliferation of NSCLC cells, promote tumor regression and prolong survival in mouse model of NSCLC by activating cGAS/STING signaling, and this in turn potentiate the immune microenvironment.

Polygenic risk score for prediction of radiotherapy efficacy and radiosensitivity in patients with non-metastatic breast cancer

ObjectiveTo construct a novel polygenic risk scoring model, in order to predict the benefits of radiosensitivity in patients with non-metastatic breast cancer (NMBC). MethodsA total of 450 NMBC patients from The Cancer Genome Atlas (TCGA) were enrolled and randomly assigned 6:4 (training vs. validation). The empirical Bayes differential analysis was used to perform differential expression analysis, univariate Cox regression and Kaplan-Meier analysis were used to screen for prognosis-related genes. Finally, LASSO regression and stepwise regression were used to select key prognostic-related genes. We constructed a multivariate Cox proportional risk regression model using key genes. The pRRophetic function was used to predict drug sensitivity of radiosensitivity (RS) and radioresistance (RR) groups for adjuvant therapy. ResultsEight genes (AMH, H2BU1, HOXB13, TMEM132A, TMEM270, ODF3L1, RIIAD1 and RIMBP2) were screened to build a polygenic risk scoring model. The region of characteristic (ROC) curves were drawn based on the 3-, 5- and 10-year overall survival (OS), with area under curves (AUCs) of 0.816, 0.822 and 0.806, respectively. RS and RR can be effectively distinguished according to the risk score of 2.004. Gene set enrichment analysis (GSEA) showed that necroptosis was significantly enriched in RS, while complement and coagulation cascade, JAK-STAT and PPAR signaling pathways were significantly enriched in RR. Alternatively, for those radioresistant patients, the chemotherapy drugs that might be more helpful are Cisplatin, Docetaxel, Methotrexate and Vinblastine with higher drug sensitivity. ConclusionThe polygenic risk scoring model showed prediction for the benefit of radiotherapy in NMBC patients, which might be used to guide clinical practice.

Sensitization of Patient-Derived Colorectal Cancer Organoids to Photon and Proton Radiation by Targeting DNA Damage Response Mechanisms.

Simple SummaryRadiotherapy plays an important role in the treatment of colorectal cancer (CRC). Approximately one-third of patients with rectal cancer show a pathological complete response upon total neoadjuvant treatment. Patient-derived CRC organoids were investigated regarding their radiotherapeutic treatment response—both in terms of conventional photon irradiation, the combination thereof with chemotherapy, as well as proton irradiation. By inhibition of an important sensor molecule for DNA damage, which has been shown to be activated upon irradiation, radioresistant organoids could be resensitized.Pathological complete response (pCR) has been correlated with overall survival in several cancer entities including colorectal cancer. Novel total neoadjuvant treatment (TNT) in rectal cancer has achieved pathological complete response in one-third of the patients. To define better treatment options for nonresponding patients, we used patient-derived organoids (PDOs) as avatars of the patient’s tumor to apply both photon- and proton-based irradiation as well as single and combined chemo(radio)therapeutic treatments. While response to photon and proton therapy was similar, PDOs revealed heterogeneous responses to irradiation and different chemotherapeutic drugs. Radiotherapeutic response of the PDOs was significantly correlated with their ability to repair irradiation-induced DNA damage. The classical combination of 5-FU and irradiation could not sensitize radioresistant tumor cells. Ataxia-telangiectasia mutated (ATM) kinase was activated upon radiation, and by inhibition of this central sensor of DNA damage, radioresistant PDOs were resensitized. The study underlined the capability of PDOs to define nonresponders to irradiation and could delineate therapeutic approaches for radioresistant patients.

MiR-148a promotes cell sensitivity through downregulating SOS2 in radiation-resistant non-small cell lung cancer cells.

Non-small cell lung carcinoma (NSCLC) is the most common type of lung cancer; however, radioresistance is a significant barrier in NSCLC radiotherapy. MicroRNA (miR)-148a has been reported to be a tumor suppressor in various types of cancer, including NSCLC. In the present study, the potential role of miR-148a in regulating radiosensitivity of NSCLC cells was investigated. Serum miR-148a expression was evaluated by reverse transcription-quantitative PCR in patients with NSCLC and healthy controls. The effects of miR-148a on cell viability, migration and invasion were assessed by Cell Counting Kit-8 and Transwell assays in radiation-resistant NSCLC cells. Serum miR-148a was downregulated in patients with NSCLC compared with healthy controls and its expression was significantly increased after radiotherapy. By contrast, miR-148a expression was decreased in the radioresistant patients compared with the radiosensitivity patients. Additionally, miR-148a overexpression inhibited the cell proliferation, migration and invasion of radiation-resistant NSCLC cells. In addition, miR-148a had putative binding site with Son of Sevenless 2 (SOS2) and negatively regulated SOS2 expression. Silencing SOS2 expression significantly suppressed miR-148a inhibitor-induced increase in radiosensitivity in NSCLC. In conclusion, the results of the present study suggested that miR-148a could enhance the radiosensitivity of NSCLC cells through targeting SOS2, thus providing potential therapeutic targets to improve radiotherapy in NSCLC.

MiR-625-3p Regulates Transcription Factor 21 (TCF21) Expression to Enhance Radio-resistance of Hepatoma Cells

ABSTRACT miR-625-3p regulates cell functions in various cancers. However, its role in radio-resistance in hepatoma remains to be unveiled. This study aims at investigating the functions of miR-625-3p in hepatoma. RTPCR detected miR-625-3p/TCF21 expression in hepatoma tissues and cell line. MTT assays were conducted to analyze the miR-625-3p role in regulations of radio-resistance of hepatoma cells. Overall survival was evaluated in correlation to miR-625-3p among patients. Luciferase reporter experiments validated the predicted TCF21 as miR-625-3p target. Higher miR-625-3p expression was discovered in hepatoma patients. In tissues of radio resistant patients, miR-625-3p was higher. The overexpression of miR-625-3p increased the radio-resistance of hepatoma cells to irradiation. miR-625-3p adversely moderated TCF21 via binding to the 3’UTR of TCF21. Downregulating miR-625-3p promoted the cell sensitivity to irradiation, which was reversed by TCF21 inhibition.

Regenerating gene IA predicts radiosensitivity and survival in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is a common malignancy in Southern China and Southeast Asia. Radiotherapy is the main treatment option. However, radiotherapy does not benefit all patients because there is no known precise biomarker that can be used for screening radioresistant patients. Genetic predisposition is closely related to tumor development, therapeutic response, and prognosis. The relationship between regenerating gene IA (REGIA) and NPC is unclear. This study aimed to retrospectively analyze the association between REGIA expression and metastasis, radiosensitivity, and survival in patients with NPC as well as assess the effect of radiation on REGIA expression in vitro. Immunohistochemical staining was used to detect REGIA. The relationship between REGIA expression in radioresistant NPC and the prognosis of CNE1 NPC cells were analyzed using quantitative real-time polymerase chain reaction and Western blotting. We found that increased doses of radiation in CNE1 cells significantly decreased REGIA expression (P<0.05). The overall rate of REGIA-positive expression was 47.15% in NPC tissues and 45.00% and 61.02% in radiosensitive and radioresistant cases, respectively, showing significant differences (P<0.05). A REGIA-positive protein expression rate had a negative correlation with radiosensitivity in NPC (r= -0.109, P=0.047). Both REGIA-positive and REGIA-negative expression strongly predicted the overall survival rate and progression-free survival of NPC patients (P<0.01). A multivariate analysis indicated that REGIA was an inverse prognostic factor in NPC patients (REGIA-positive expression: hazard ratio (HR)=2.139, 95% confidence interval (CI)=1.56-2.94, P<0.001 and REGIA-negative expression: HR=1.958, 95% CI=1.42-2.69, P<0.001). In conclusion: Radiation can affect REGIA expression. The REGIA expression level correlated with radioresistance and a poor prognosis. In addition, REGIA expression might act as a potential therapeutic target and prognostic predictor in NPC patients.

USP21 regulates Hippo signaling to promote radioresistance by deubiquitinating FOXM1 in cervical cancer.

The ectopic expression of ubiquitin-specific peptidase 21 (USP21) is common in different types of cancer. However, its relationship with radio-sensitivity in cervical cancer (CC) remains unclear. In this study, we aimed to uncover the effect of USP21 on CC radio-resistance and its underlying mechanism. Our results showed that the expression of USP21 was markedly increased in CC tissues of radio-resistant patients and CC cells treated with radiation. Besides, knockdown of USP21 restrained the survival fractions, and facilitated apoptosis of CC cells in the absence or presence of radiation. Additionally, USP21 in combination with FOXM1 regulated the stability and ubiquitination of FOXM1. However, FOXM1 reversed the effects of USP21 knockdown on the radio-resistance of CC cells. Furthermore, FOXM1 knockdown activated the Hippo pathway by inhibiting the nuclear translocation of Yes-associated protein 1 (YAP1), and FOXM1 knockdown attenuated the radio-resistance of CC cells via inhibiting the Hippo-YAP1 pathway. USP21 activated the Hippo pathway by mediating FOXM1. Knockdown of USP21 enhanced the radio-sensitivity of CC cells in vivo. In summary, USP21 contributed to the radio-resistance of CC cells via FOXM1/Hippo signaling, and may serve as a promising target for radio-sensitizers in the radiotherapy of CC.

M2 macrophage-derived exosomal long non-coding RNA AGAP2-AS1 enhances radiotherapy immunity in lung cancer by reducing microRNA-296 and elevating NOTCH2

Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) play vital roles in human diseases. We aimed to identify the effect of the lncRNA AGAP2 antisense RNA 1 (AGAP2-AS1)/miR-296/notch homolog protein 2 (NOTCH2) axis on the progression and radioresistance of lung cancer. Expression of AGAP2-AS1, miR-296, and NOTCH2 in lung cancer cells and tissues from radiosensitive and radioresistant patients was determined, and the predictive role of AGAP2-AS1 in the prognosis of patients was identified. THP-1 cells were induced and exosomes were extracted, and the lung cancer cells were respectively treated with silenced AGAP2-AS1, exosomes, and exosomes upregulating AGAP2-AS1 or downregulating miR-296. The cells were radiated under different doses, and the biological processes of cells were assessed. Moreover, the natural killing cell-mediated cytotoxicity on lung cancer cells was determined. The relationships between AGAP2-AS1 and miR-296, and between miR-296 and NOTCH2 were verified. AGAP2-AS1 and NOTCH2 increased while miR-296 decreased in radioresistant patients and lung cancer cells. The malignant behaviors of radioresistant cells were promoted compared with the parent cells. Inhibited AGAP2-AS1, macrophage-derived exosomes, and exosomes overexpressing AGAP2-AS1 or inhibiting miR-296 facilitated the malignant phenotypes of radioresistant lung cancer cells. Furthermore, AGAP2-AS1 negatively regulated miR-296, and NOTCH2 was targeted by miR-296. M2 macrophage-derived exosomal AGAP2-AS1 enhances radiotherapy immunity in lung cancer by reducing miR-296 and elevating NOTCH2. This study may be helpful for the investigation of radiotherapy of lung cancer.

RWR-algorithm-based dissection of microRNA-506-3p and microRNA-140-5p as radiosensitive biomarkers in colorectal cancer.

Radiotherapy resistance is one of the main causes for treatment failure in colorectal cancer (CRC), and it is associated with the deregulation of certain microRNAs. In this study, we constructed the microRNA-mRNA network consisting of 2275 microRNAs and 7045 target genes, collected the known microRNAs related to CRC-radiosensitivity (CRCR) (n=18) as the seed nodes, and applied the algorithm of random walk with restart (RWR) to the network to identify novel CRCR-related microRNAs (n=263). In functional analysis, 263 novel microRNAs shared a high proportion of the same biological processes and pathways with the known microRNAs. In topological analysis of the sub-network of the 263 microRNAs and their targets, hsa-mir-506-3p and hsa-mir-140-5p were identified as network hub nodes. In plasma, radiosensitive patients had a higher expression level of hsa-mir-506-3p and hsa-mir-140-5p than radioresistant patients. In experimental validation, both hsa-mir-506-3p and hsa-mir-140-5p over-expression could obviously decrease the cell proliferation, survival rate and colonality in CRC cells after radiation. In conclusion, this study combined the novel network-based method with experimental validation, and identified two novel radiosensitive biomarkers of hsa-mir-506-3p and hsa-mir-140-5p in CRC.

Knockdown of LINC00473 promotes radiosensitivity of non-small cell lung cancer cells via sponging miR-513a-3p

Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. Radioresistance is a significant obstacle in NSCLC radiotherapy. Long non-coding RNA LINC00473 has been found to impact the radiotherapy in several malignant tumours. This study aimed to investigate the underlying role and mechanism of LINC00473 in regulating radiosensitivity of NSCLC cells. The levels of LINC00473 and miR-513a-3p were measured by quantitative Real-Time PCR. The relationship of LINC00473 with overall survival was tested by the Kaplan-Meier method. The effects of LINC00473 on cell viability and cell survival were assessed by cell counting kit-8 (CCK-8) and colony survival assay in NSCLC cells exposed to different doses of radiation. A luciferase reporter assay was used to investigate the correlation between LINC00473 and miR-513a-3p. The present study showed that the relative LINC00473 expression was upregulated and miR-513a-3p expression was downregulated in radioresistant NSCLC patients compared with radiosensitive patients. And upregulated LINC00473 expression was associated with poor prognosis of NSCLC patients after radiotherapy. Radiation led to an increase in LINC00473 expression in a dose- and time-dependent manner. The knockdown of LINC00473 markedly promoted radiosensitivity in NSCLC cells under different doses of radiation. LINC00473 was a sponge of miR-513a-3p and negatively regulated the miR-513a-3p expression. In conclusion, the inhibition of miR-513a-3p markedly reversed the promoted effect of LINC00473 knockdown on cell radiosensitivity. LINC00473 inhibition enhances radiosensitivity of NSCLC by sponging miR-513a-3p, providing a promising therapeutic target to increase the sensitivity of radiotherapy in NSCLC patients.

MiR-219a-5p enhances the radiosensitivity of non-small cell lung cancer cells through targeting CD164

Lung cancer is one of the leading causes of cancer-associated mortality. Non-small cell lung carcinoma (NSCLC) accounts for 70–85% of the total cases of lung cancer. Radioresistance frequently develops in NSCLC in the middle and later stages of radiotherapy. We investigated the role of miR-219a-5p in radioresistance of NSCLC. miR-219a-5p expression in serum and lung tissue of lung cancer patients was lower than that in control. Compared with radiosensitive (RS) NSCLC patients, miR-219a-5p expression was decreased in serum and lung tissue in radioresistant patients. miR-219a-5p expression level was negatively associated with radioresistance in NSCLC cell lines. Up-regulation of miR-219a-5p increased radiosensitivity in radioresistant NSCLC cells in vitro and in vivo. Down-regulation of miR-219a-5p decreased radiosensitivity in radiosensitive A549 and H358 cells. miR-219a-5p could directly bind in the 3′UTR of CD164 and negatively regulated CD164 expression. CD164 expression was higher in radioresistant NSCLC tissues than RS tissues. Up-regulation of CD164 significantly inhibited miR-219a-5p-induced regulation of RS in radioresistant A549 and H358 cells. Down-regulation of CD164 significantly inhibited the effect of anti-miR-219a-5p on radiosensitive A549 and H358 cells. miR-219a-5p or down-regulation of CD164 could increase apoptosis and γ-H2A histone family member X (γ-H2AX) expression in radioresistant cells in vitro and in vivo. Up-regulation of CD164 could inhibit the effect of miR-219a-5p on apoptosis and γ-H2AX expression. Our results indicated that miR-219a-5p could inhibit CD164, promote DNA damage and apoptosis and enhance irradiation-induced cytotoxicity. The data highlight miR-219a-5p/CD164 pathway in the regulation of radiosensitivity in NSCLC and provide novel targets for potential intervention.

Differentially Expressed MicroRNAs in Radioresistant and Radiosensitive Atypical Meningioma: A Clinical Study in Chinese Patients.

Background: For atypical meningiomas (AMs), the combination of gross total resection (GTR) and adjuvant radiotherapy (ART) is still a controversial therapeutic strategy to improve prognosis. This study analyzed the factors influencing the prognosis on AM patients treated with GTR + ART by investigating both clinical characteristics and the change in microRNA (miRNA) expression.Materials and Methods: Adult AM patients who were admitted to the Tiantan hospital from 2008 to 2015 and underwent GTR + ART were included. Patients who suffered recurrence within 3 years after operation were considered radioresistant, while the others were considered radiosensitive. Clinical characterizations were compared between these two groups. The microRNA (miRNA) expression was detected via miRNA microarray in 10 patients, five from the radiosensitive group and from the radioresistant group.Results: A total of 55 cases were included in this study. No significant difference was found in the clinical characteristics (gender, age, tumor location, tumor size, peritumoral brain edema, and Ki-67 index) between radiosensitive and radioresistant patients. We found seven significantly upregulated miRNAs (miR-4286, miR-4695-5p, miR-6732-5p, miR-6855-5p, miR-7977, miR-6765-3p, miR-6787-5p) and seven significantly downregulated miRNAs (miR-1275, miR-30c-1-3p, miR-4449, miR-4539, miR-4684-3p, miR-6129, miR-6891-5p) in patients resistant to radiotherapy. The differentially expressed miRNAs were enriched mostly in the fatty acid metabolic pathways (hsa00061, hsa01212) and transforming growth factor beta signaling pathway (hsa04350).Conclusion: For AM patients treated with GTR + ART, the changes in miRNA expression discovered in this study may be a potential predictor of individual sensitivity to adjuvant radiotherapy. Further research is needed regarding the predictive power and mechanism by which these miRNAs influence prognosis.

TRIM21\u2013SERPINB5 aids GMPS repression to protect nasopharyngeal carcinoma cells from radiation-induced apoptosis

BackgroundThe main strategy against nasopharyngeal carcinoma (NPC) is radiotherapy. However, radioresistance mediated recurrence is a leading clinical bottleneck in NPC. Revealing the mechanism of NPC radioresistance will help improve the therapeutic effect.MethodsIn this study, the role of TRIM21 (tripartite motif–containing 21) in NPC receiving ionizing radiation was firstly examined both in vivo and in vitro. Mass spectrometry analysis was performed to identify the downstream targets of TRIM21. NPC cells with TRIM21 or SERPINB5 (serpin family B member 5) overexpression or knockout were used to determine the epistatic relationship among SERPINB5, GMPS (guanine monophosphate synthase) and TRIM21. Flow cytometry, co-immunoprecipitation, western blot and immunofluorescence were employed to strengthen the results. Finally, immunohistochemistry using 4 radiosensitive and 8 radioresistent NPC patient samples was perform to examine the association between SERPINB5 or GMPS expression and patient radio-sensitivity.ResultsAs an E3 ligase, TRIM21 was highly expressed in NPC. After ionizing radiation, TRIM21 repressed TP53 expression by mediating GMPS ubiquitination and degradation. Overexpression of TRIM21 protected NPC cells from radiation mediated cell apoptosis in vitro and in vivo. Further analysis revealed that TRIM21 mediated GMPS repression was dependent on SERPINB5, and SERPINB5 served as an adaptor which prevented GMPS from entering into the nucleus and introduced TRIM21 for GMPS ubiquitination. Moreover, the in vitro and in vivo results validated the finding that SERPINB5 promoted NPC cell radioresistance, and the radioresistant patients had higher SERPINB5 expression.ConclusionsOverall, our data showed that TRIM21–SERPINB5-mediated GMPS degradation facilitated TP53 repression, which promoted the radioresistance of NPC cells. This novel working model related to TP53 suppression provided new insight into NPC radioresistence clinically.

Downregulation of TMPRSS4 Enhances Triple-Negative Breast Cancer Cell Radiosensitivity Through Cell Cycle and Cell Apoptosis Process Impairment.

Background:Radioresistance remains a challenge for cancer radiotherapy. The present study aims to investigate the role of TMPRSS4 in triple negative breast cancer (TNBC) cell radiosensitivity. Materials and Methods:After transfection of MDA-MD-468 triple negative breast cancer cells line by using the lentivirus vector, the effect of TMPRSS4 down-regulation on TNBC radiosensitivity was evaluated by using cloning assay and CCK-8 assay. The CCK-8 assay was also used for performing cell proliferation analysis. Western blot was carried out to detect the expression of certain proteins related to cell cycle pathways (cyclin D1), cell apoptosis pathways (Bax, Bcl2, and Caspase3), DNA damage and DNA damage repair (TRF2, Ku80 , ˠH2AX) . The cell cycle and cell apoptosis were also investigated using flow cytometer analysis. Results: TMPRSS4 expression was down-regulated in MDA-MB-468 cells which enhanced MDA-MB-468 cells radiosensitivity. TMPRSS4 silencing also improved IR induced cell proliferation ability reduction and promoted cell arrested at G2/M phase mediated by 6 Gy IR associated with cyclin D1 expression inhibition. Moreover, TMPRSS4 inhibition enhanced TNBC apoptosis induced by 6 Gy IR following by over-expression of (Bax, Caspase3) and down-regulation of Bcl2 as the pro-apoptotic and anti-apoptotic proteins, respectively. Otherwise, TMPRSS4 down-regulation increases DNA damage induced by 6 Gy IR and delays DNA damage repair respectively illustrated by downregulation of TRF2 and permanent increase of Ku80 and ˠH2AX expression at 1 h and 10 h post-IR. Conclusion:Down-regulation of TMPRSS4 increases triple negative breast cancer cell radiosensitivity and the use of TMPRSS4 inhibitor can be encouraged for improving radiotherapy effectiveness in TNBC radioresistant patients.

Identification of differentially expressed genes to predict radioresistant prostate carcinomas.

57 Background: Although relapses after radiotherapy are common in prostate cancer (PCa) patients, there are no clinical models or markers to identify patients at high risk for radioresistance. So far, only in vitro studies and xenograft models have been performed to identify gene expression patterns associated with radioresistance. However, studies which address the protein pattern to predict radioresistance in humans are completely missing. In order to determine potential biomarkers for radioresistance, we compared protein expression profiles of radioresistant PCa patients with PCa of primary prostatectomized patients. Methods: Two study groups consisting of: I) 30 patients who were treated by salvage prostatectomy and II) 94 patients treated by primary prostatectomy were formed. Tissue microarrays were constructed and immunostained for 15 proteins which are suggested to be associated with radioresistance by in vitro findings. Kruskal-Wallis test was used for multiple group comparison and followed by Dunn-Bonferroni-Test to detect intergroup differences. Cohen’s d was used to calculate the intergroup effect size. Results: Most proteins studied did not show any relevant differences between radioresistant PCa and primary PCa, except for two (AR and AKR1C3). On comparing immunostaining patterns between radioresistant PCa and primary PCa separated by Gleason risk groups, we observed only AR (androgen receptor) to be most expressed in radioresistant PCa (89.7%) and, in 87.8% of primary PCa of the high-risk group ( &gt; 7a) (p = 0.851, Cohen’s d = 0.05), while only 67.3% PCa of the low-risk group (≤7a) (p = 0.017, Cohen’s d = 0.55) were positive. Considering the highest Gleason pattern per patient, only AKR1C3 (Aldo-Keto Reductase Family 1 Member C3) was seen to be similarly expressed in radiation-resistant PCa and patients with Gleason patterns 4 and 5 (p = 0.827, Cohen’s d = 0.05 and p = 0.893, Cohen’s d = 0.10) as compared to Gleason pattern 3 (p = 0.20, Cohen’s d = 0.69) in primary PCa. Conclusions: This is the first study evaluating protein expression profiles to predict radioresistance in PCa, where AR and AKR1C3 were identified to be the most promising protein markers.

MicroRNA-15b-5p Predicts Locoregional Relapse in Head and Neck Carcinoma Patients Treated With Intensity-modulated Radiotherapy.

Head and neck cancers are a heterogenous group of epithelial tumors represented mainly by squamous cell carcinomas (HNSCC), which are the sixth most common type of cancer worldwide. Surgery together with radiotherapy (RT) is among the basic treatment modalities for most HNSCC patients. Various biomarkers aiming to predict patients' response to RT are currently investigated. The reason behind this effort is, on one hand, to distinguish radioresistant patients that show weak benefit from RT and, on the other hand, reduce the ionizing radiation dose in less aggressive radiosensitive HNSCC with possibly less acute or late toxicity. A total of 94 HNSCC patients treated by definitive intensity-modulated radiotherapy were included in our retrospective study. We used a global expression analysis of microRNAs (miRNAs) in 43 tumor samples and validated a series of selected miRNAs in an independent set of 51 tumors. We identified miR-15b-5p to be differentially expressed between patients with short and long time of locoregional control (LRC). Kaplan-Meier analysis confirmed that HNSCC patients with higher expression of miR-15b-5p reach a significantly longer locoregional relapse-free survival compared to patients expressing low levels. Finally, multivariable Cox regression analysis revealed that miR-15b-5p is an independent predictive biomarker of LRC in HNSCC patients (HR=0.25; 95% CI=0.05-0.78; p<0.016). miR-15b-5p represents a potentially helpful biomarker for individualized treatment decisions concerning the management of HNSCC patients.

A network approach to quantifying radiotherapy effect on cancer: Radiosensitive gene group centrality

Radiotherapy plays a vital role in cancer treatment, for which accurate prognosis is important for guiding sequential treatment and improving the curative effect for patients. An issue of great significance in radiotherapy is to assess tumor radiosensitivity for devising the optimal treatment strategy. Previous studies focused on gene expression in cells closely associated with radiosensitivity, but factors such as the response of a cancer patient to irradiation and the patient survival time are largely ignored. For clinical cancer treatment, a specific pre-treatment indicator taking into account cancer cell type and patient radiosensitivity is of great value but it has been missing. Here, we propose an effective indicator for radiosensitivity: radiosensitive gene group centrality (RSGGC), which characterizes the importance of the group of genes that are radiosensitive in the whole gene correlation network. We demonstrate, using both clinical patient data and experimental cancer cell lines, which RSGGC can provide a quantitative estimate of the effect of radiotherapy, with factors such as the patient survival time and the survived fraction of cancer cell lines under radiotherapy fully taken into account. Our main finding is that, for patients with a higher RSGGC score before radiotherapy, cancer treatment tends to be more effective. The RSGGC can have significant applications in clinical prognosis, serving as a key measure to classifying radiosensitive and radioresistant patients.

Abstract 1854: Treatment of head and neck squamous cell carcinoma cells with BMS754807 and Dasatinib induce synergistic cytotoxicity through altered focal adhesion signaling

Abstract Head and neck cancer (HNC) is the 6th most common cancer worldwide and the 9th most common cancer in the United States. Singular, targeted cancer therapies rarely produce a robust, complete and durable response and often do not substantially prolong patient survival. Adaptive survival responses often blunt the cytotoxic effects of drugs resulting in resistance. Therefore, targeting compensatory signaling pathways may provide improved therapeutic responses. Even with the current best treatment, 5-year survival for all patients with head and neck squamous cell carcinomas (HNSCC) is only approximately 65%, further highlighting the need for improved combinatorial treatments. Previous work in our laboratory has shown that inhibitors of Insulin Like Growth Factor 1 Receptor (IGF1R) and Src family kinases, when used in combination, synergistically inhibit HNSCC growth in vitro. Therefore, to explore the mechanisms which may contribute to this synergistic cytotoxicity, we utilized reverse phase protein arrays to assess the proteome of HNSCC lines treated with BMS754807 and Dasatinib to inhibit IGF1R and Src, respectively. We identified focal adhesion signaling as a potentially vital node in the cell signaling network of synergistic cytotoxicity upon treatment of HNSCC with BMS754807 and Dasatinib. Focal Adhesion Kinase (FAK) and Paxillin phosphorylation was decreased synergistically with the combination of BMS754807 and Dasatinib. Using western blot analysis, we confirmed a decrease in phosphorylation of FAK Y576/577 and Paxillin Y118 upon combined treatment with BMS754807 and Dasatinib. Interestingly, FAK is upregulated in radioresistant HNSCC patients and, metastases have increased phosphorylation of FAK compared to normal tissues. FAK is amplified in up to 26% of HNSCC and overexpression of Paxillin is associated with unfavorable prognosis, highlighting the importance of focal adhesion signaling in head and neck cancers. Our data suggests that interactions between integrins, receptor tyrosine kinase, and non-receptor kinase signaling regulate cell survival in HNSCC. Disruption of IGFR and Src activity leads to convergent inhibition of focal adhesion signaling and synergistic cytotoxicity in a variety of HNSCC cell lines. Citation Format: Christine E. Lehman, Rolando MEndez, Mark Axelrod, Julia Wulfkuhle, Emanuel Petricoin, Daniel Gioeli, Mark Jameson. Treatment of head and neck squamous cell carcinoma cells with BMS754807 and Dasatinib induce synergistic cytotoxicity through altered focal adhesion signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1854.