Clinicopathological significance of survivin expression in patients with cervical cancer: A systematic meta-analysis

Genome editing approaches with CRISPR/Cas9: the association of NOX4 expression in breast cancer patients and effectiveness evaluation of different strategies of CRISPR/Cas9 to knockout Nox4 in cancer cells

BACKGROUND

The increasing prevalence of cancer detection necessitated practical strategies to deliver highly accurate, beneficial, and dependable processed information together with experimental results. We deleted the cancer biomarker NOX4 using three novel genetic knockout (KO) methods. Homology-directed repair (HDR), Dual allele HITI (Du-HITI) and CRISPR-excision were utilized in this study.

METHODS

The predictive value of the NOX4 expression profile was assessed using a combined hazard ratio (HR) with a 95% confidence interval (CI). With a 95% confidence interval, a pooled odd ratio (OR) was used to calculate the relationship between NOX4 expression patterns and cancer metastasis. There were 1060 tumor patients in all sixteen research that made up this meta-analysis. To stop the NOX4 from being transcribed, we employed three different CRISPR/Cas9-mediated knockdown methods. The expression of RNA was assessed using RT-PCR. We employed the CCK-8 assay, colony formation assays, and the invasion transwell test for our experiments measuring cell proliferation and invasion. Using a sphere-formation test, the stemness was determined. Luciferase reporter tests were carried out to verify molecular adhesion. Utilizing RT-qPCR, MTT, and a colony formation assay, the functional effects of NOX4 genetic mutation in CRISPR-excision, CRISPR-HDR, and CRISPR du-HITI knockdown cell lines of breast cancer were verified.

RESULTS

There were 1060 malignant tumors in the 16 studies that made up this meta-analysis. In the meta-analysis, higher NOX4 expression was linked to both a shorter overall survival rate (HR = 1.93, 95% CI 1.49-2.49, P < 0.001) and a higher percentage of lymph node metastases (OR = 3.22, 95% CI 2.18-4.29, P < 0.001). In breast carcinoma cells, it was discovered that NOX4 was overexpressed, and this increase was linked to a poor prognosis. The gain and loss-of-function assays showed enhanced NOX4 breast carcinoma cell proliferation, sphere-forming capacity, and tumor development. To activate transcription, the transcriptional factor E2F1 also attaches to the promoter region of the Nanog gene. The treatment group (NOX4 ablation) had substantially more significant levels of proapoptotic gene expression than the control group (P < 0.01). Additionally, compared to control cells, mutant cells expressed fewer antiapoptotic genes (P < 0.001). The du-HITI technique incorporated a reporter and a transcription termination marker into the two target alleles. Both donor vector preparation and cell selection were substantially simpler using this approach than with "CRISPR HDR" or "CRISPR excision." Furthermore, single-cell knockouts for both genotypes were created when this method was applied in the initial transfection experiment.

CONCLUSIONS

The NOX4 Knockout cell lines generated in this research may be used for additional analytical studies to reveal the entire spectrum of NOX4 activities. The du-HITI method described in this study was easy to employ and could produce homozygous individuals who were knockout for a specific protein of interest.

Metabolism-associated molecular classification of cervical cancer

OBJECTIVE

This study aimed to explore metabolic abnormalities in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) for metabolism-related genes.

METHODS

We downloaded expression data for metabolism-related genes, performed differential expression analysis, and applied weighted gene co-expression network analysis (WGCNA) to identify metabolism-related functional modules. We obtained normalised miRNA expression data and identified master methylation regulators for metabolism-related genes. Cox regression of data on metabolism-related genes was performed to screen for genes that affect the prognosis of patients with CESC. Furthermore, we selected key genes for validation.

RESULTS

Our results identified 3620 metabolism-related genes in CESC, 2493 of which contained related mutations. The co-occurrence of CUBN, KALRN, and HERC1 was related to the prognosis of CESC. The fraction of genome altered (FGA) closely correlated with overall survival. In expression analysis, 374 genes were related to the occurrence and prognosis of CESC. We then identified four metabolic pathway modules in WGCNA. Further analysis revealed that glycolysis/gluconeogenesis was related to endothelial cells and that arachidonic acid metabolism was related to cell proliferation. These four modules were also related to the prognosis of CESC. Among CESC-related metabolic genes, two genes were found to be regulated by microRNAs (miRNAs) and methylation, whereas another two genes were coregulated by miRNAs and mutations.

CONCLUSIONS

Among metabolism-related genes, 15 genes were related to the prognosis of CESC. The co-occurrence of CUBN/KALRN/HERC1 was associated with CESC prognosis. Glycolysis/gluconeogenesis was related to endothelial cells, and arachidonic acid metabolism was related to cell proliferation.

In Silico Evaluation of HN-N07 Small Molecule as an Inhibitor of Angiogenesis and Lymphangiogenesis Oncogenic Signatures in Non-Small Cell Lung Cancer

Tumor angiogenesis and lymphangiogenesis pathways have been identified as important therapeutic targets in non-small cell lung cancer (NSCLC). Bevacizumab, which is a monoclonal antibody, was the initial inhibitor of angiogenesis and lymphangiogenesis that received approval for use in the treatment of advanced non-small cell lung cancer (NSCLC) in combination with chemotherapy. Despite its usage, patients may still develop resistance to the treatment, which can be attributed to various histological subtypes and the initiation of treatment at advanced stages of cancer. Due to their better specificity, selectivity, and safety compared to chemotherapy, small molecules have been approved for treating advanced NSCLC. Based on the development of multiple small-molecule antiangiogenic drugs either in house and abroad or in other laboratories to treat NSCLC, we used a quinoline-derived small molecule-HN-N07-as a potential target drug for NSCLC. Accordingly, we used computational simulation tools and evaluated the drug-likeness properties of HN-N07. Moreover, we identified target genes, resulting in the discovery of the target BIRC5/HIF1A/FLT4 pro-angiogenic genes. Furthermore, we used in silico molecular docking analysis to determine whether HN-N07 could potentially inhibit BIRC5/HIF1A/FLT4. Interestingly, the results of docking HN-N07 with the BIRC5, FLT4, and HIF1A oncogenes revealed unique binding affinities, which were significantly higher than those of standard inhibitors. In summary, these results indicate that HN-N07 shows promise as a potential inhibitor of oncogenic signaling pathways in NSCLC. Ongoing studies that involve in vitro experiments and in vivo investigations using tumor-bearing mice are in progress, aiming to evaluate the therapeutic effectiveness of the HN-N07 small molecule.

CRISPR/Cas9-mediated LINC00511 knockout strategies, increased apoptosis of breast cancer cells via suppressing antiapoptotic genes

Background

The growing detection of long noncoding RNAs (lncRNAs) required the application of functional approaches in order to provide absolutely precise, conducive, and reliable processed information along with effective consequences. We utilized genetic knockout (KO) techniques to ablate the Long Intergenic Noncoding RNA 00,511 gene in several humans who suffered from breast cancer cells and at the end we analyzed and examined the results.

Results

The predictive relevance of LINC00511 expression pattern was measured by using a pooled hazard ratio (HR) with a 95% confidence interval (CI). The link among LINC00511 expression profiles and cancer metastasis was measured by using a pooled odds ratio (OR) with a 95% confidence interval. This meta- analysis was composed of fifteen studies which contained a total of 1040 tumor patients. We used three distinct CRISPR/Cas9-mediated knockdown techniques to prevent the LINC00511 lncRNA from being transcribed. RT-PCR was used to measure lncRNA and RNA expression. We used CCK-8, colony formation tests, and the invasion transwell test to measure cell proliferation and invasion. The stemness was measured by using a sphere-formation test. To validate molecular attachment, luciferase reporter assays were performed. The functional impacts of LINC00511 gene deletion in knockdown breast cancer cell lines were confirmed by using RT-qPCR, MTT, and a colony formation test. This meta-analysis was composed of 15 trials which contained a total of 1040 malignant tumors. Greater LINC00511 expression was ascribed to a lower overall survival (HR = 1.93, 95% CI 1.49–2.49, < P 0.001) and to an increased proportion of lymph node metastasis (OR = 3.07, 95% CI 2.23–4.23, P < 0.001) in the meta‐analysis. It was found that the role of LINC00511 was overexpressed in breast cancer samples, and this overexpression was ascribed to a poor prognosis. The gain and loss-of-function tests demonstrated findings such as LINC00511 increased breast cancer cell proliferation, sphere-forming ability, and tumor growth. Additionally, the transcription factor E2F1 binds to the Nanog gene's promoter site to induce transcription. P57, P21, Prkca, MDM4, Map2k6, and FADD gene expression in the treatment group (LINC00511 deletion) was significantly higher than in the control group (P < 0.01). In addition, knockout cells had lower expression of BCL2 and surviving genes than control cells P < 0.001). In each of the two target alleles, the du-HITI approach introduced a reporter and a transcription termination signal. This strategy's donor vector preparation was significantly easier than "CRISPR HDR," and cell selection was likewise much easier than "CRISPR excision." Furthermore, when this approach was used in the initial transfection attempt, single-cell knockouts for both alleles were generated.

Conclusions

The methods employed and described in this work could be extended to the production of LINC00511 knockout cell lines and, in theory, to the deletion of other lncRNAs to study their function.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12575-022-00171-1.

The abnormal expression of chromosomal region maintenance 1 (CRM1)-survivin axis in ovarian cancer and its related mechanisms regulating proliferation and apoptosis of ovarian cancer cells

Ovarian cancer (OC) is the main type of cancer that affects the female reproductive system and has a high morbidity and mortality rate. This study aimed to explore the regulatory effect of the chromosomal region maintenance 1 (CRM1)-survivin axis on the progression of OC. Ovarian cancer cells were transfected with pcDNA3.1-survivin and short hairpin RNA (sh)-CRM1. Cell proliferation was analyzed by cell counting kit-8 (CCK8), 5-ethynyl-2´-deoxyuridine (EdU) staining, and colony formation assays. Apoptosis was detected using flow cytometry. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were performed to analyze the expression of RNA and protein, respectively. qRT-PCR and prognostic correlation analyses revealed that CRM1 is highly expressed in OC cells and related to survival. The results of qRT-PCR, CCK8, colony formation test, EdU staining, flow cytometry, and Western blotting showed that CRM1 silencing inhibited the proliferation and colony formation of OVCAR 3 and SKOV3 cells and promoted cell apoptosis by promoting Caspase-3 activation. Survivin was positively regulated by CRM1 and promoted the development of OC. The results of the rescue experiment showed that overexpression of survivin reversed the inhibitory effect of CRM1 knockdown on the proliferation of ovarian cancer cells and its inhibitory effect on apoptosis. Our findings confirm the role of the CRM1-survivin signal transduction axis in OC by regulating the proliferation and apoptosis of OC cells, and may thus serve as a potential therapeutic target for OC.

Survivin-positive circulating tumor cells as a marker for metastasis of hepatocellular carcinoma

BACKGROUND

Circulating tumor cells (CTCs) and survivin are indicators for tumor stage and metastasis, as well as epitheliomesenchymal transition, in various cancers, including hepatocellular cancer (HCC).

AIM

To explore the potential of survivin-positive CTCs, specifically, as a marker for tumor progression in HCC patients.

METHODS

We examined the survivin expression pattern in CTCs obtained from 179 HCC patients, and investigated the in vitro effects of survivin silencing and overexpression on the proliferation and invasion of HCC cells. CTC count and survivin expression in patient samples were examined using RNA in situ hybridization.

RESULTS

All 179 patients were positive for CTC markers, and 94.41% of the CTCs were positive for survivin. The CTC and survivin-positive CTC counts were significantly higher in the HCC patients than in the normal controls, and were significantly associated with tumor stage and degree of differentiation. Further, survivin overexpression was found to induce HepG2 cell proliferation, reduce apoptosis, and improve invasive ability.

CONCLUSION

Survivin shows upregulated expression (indicative of anti-apoptotic effects) in HCC. Thus, survivin-positive CTCs are promising as a predictor of HCC prognosis and metastasis, and their accurate measurement may be useful for the management of this cancer.

miR-122 Inhibits the Cervical Cancer Development by Targeting the Oncogene RAD21

Cervical cancer (CC) is one of the most frequently diagnosed tumors in female. miR-122 has been proved to be dominant in CC. The particular role of miR-122 in CC is unclear. Thus, we attempted to investigate the prognostic role of miR-122 in CC. We used the database of Kaplan-Meier curve plot. Growth and apoptosis of C33A cells were detected by CCK-8, colony formation assay, transwell assays and flow cytometry analysis. The target gene of miR-122 was identified using bioinformatics, q-PCR, western blot and luciferase assay. It showed that CC patients with overexpression of miR-122 have a better prognosis in the Kaplan-Meier plot database analysis. Overexpressed miR-122 inhibited the malignant growth and induced apoptosis of CC. miR-122 targeting of RAD21 cohesin complex component (RAD21) was identified using bioinformatics, Q-PCR, western blot and luciferase assay analyses. Moreover, we found miR-122 conduct its functions via RAD21 via the PI3K/AKT signaling pathway. Importantly, overexpression of RAD21 restored the roles of miR-122 in CC. Our data suggested that miR-122 could block malignant growth and promoted apoptosis by targeting RAD21 in CC. Our finding indicates miR-122 could potentially participate in the pathogenesis and be a biomarker or the potential therapeutic target of CC.

The role of long intergenic noncoding RNA 00511 in malignant tumors: a meta-analysis, database validation and review

Increasing studies suggested that long intergenic noncoding RNA 00511 (LINC00511) could facilitate the progression of various malignancies and correlates with prognosis of patients with malignant tumors. However, its clinical significance is still not completely clarified. Therefore, we performed a meta-analysis and bioinformatics analysis to further evaluate the correlation of LINC00511 expression level with prognosis and metastasis in patients with tumors. The pooled hazard ratio (HR) with 95% confidence interval (CI) was used to evaluate the prognostic significance of LINC00511 expression level. The pooled odds ratio (OR) with 95% CI was applied to assess the association between LINC00511 expression level and tumor metastasis. A total of 12 studies involving 1040 tumor patients were included in this meta-analysis. The pooled analyses suggested that higher LINC00511 expression level correlated with worse overall survival (OS) (HR = 1.93, 95% CI 1.49–2.49, P < 0.001) and higher incidence of lymph node metastasis (OR = 3.07, 95% CI 2.23–4.23, P < 0.001). Additionally, bioinformatics analysis based on TCGA datasets also showed that increased LINC00511 expression level may predict poor OS and disease-free survival (DFS) in patients with malignant tumors. Taken together, our finding suggested that high LINC00511 expression level may be correlated with poor prognosis and high incidence of metastasis. Nevertheless, further large-scale and high-quality studies are needed to validate our findings.

Targeting survivin sensitizes cervical cancer cells to radiation treatment

Survivin is an inhibitor of apoptosis protein that functions to inhibit apoptosis, promote proliferation, and enhance invasion. It is selectively up-regulated in many human tumors and implicated in cellular radiation response through its role in apoptosis, cell division, and DNA damage response. This study aimed to investigate the effect and mechanisms of targeting survivin radiosensitivity in cervical cancer C33A cells. Here, the authors designed a small interfering RNA (siRNA) or plasmid-based small hairpin RNA (shRNA) targeting survivin and tested its effects on radiosensitivity to ionizing radiation (IR) treatment of C33A cells in vitro, as well as on the tumorigenicity of C33A cells in nude mice in vivo. Transient transfection of survivin siRNA into C33A cells suppressed survivin expression, induced cell apoptosis and G2/M arrest and reduced cell proliferation, clone formation ability after IR, followed by p53 upregulated modulator of apoptosis (PUMA) upregulation. But, transient transfection of survivin siRNA alone has no significant effect on cell growth and apoptosis. To confirm that PUMA upregulation is necessary for survivin silencing -induced radiosensitivity to IR treatment, the effect of targeting PUMA in survivin sliencing cells was observed. The results showed that targeting PUMA in survivin sliencing cells rescued C33A cells’ radioresistance. Furthermore, knocking down survivin expression combined with IR treatment significantly slowed tumor growth and promoted tumor cell apoptosis in C33A xenografted tumors. It was concluded that survivin played a role in radiotherapy resistance. Targeting survivin increased the radiosensitivity of C33A cells through induction of PUMA expression.

Molecular characterization of an inhibitor of apoptosis protein (IAPs) in freshwater pearl mussel, Hyriopsis schlegelii

The inhibitor of apoptosis proteins (IAPs) played important roles in inhibiting the apoptosis of tumor cells by regulating caspase activity in mammals. In this study, we first cloned the full-length cDNA sequence of IAPs gene (designated as Hs-IAPs) in Hyriopsis schlegelii. The Hs-IAPs gene contained an open reading frame of 1719 nucleotides, encoding a predicted protein of 572 amino acids. qRT-PCR assay indicated that the Hs-IAPs gene was ubiquitously expressed in different tissues, and the highest expression level was in gills. Furthermore, we purified and obtained the recombinant protein of Hs-IAPs which showed a molecular weight of 82.5 kDa. We used H₂O₂ stimulation experiment to explore the possible function of Hs-IAPs. The results showed that the percentage of viable cells significantly increased following the Hs-IAPs concentration. These indicated that the Hs-IAPs may play a role in anti-oxidation causing by H₂O₂, and its anti-oxidative may be crucial in the process of apoptosis.

miR-122-5p modulates the radiosensitivity of cervical cancer cells by regulating cell division cycle 25A (CDC25A)

Cervical cancer is one of the most common gynecological malignancies globally, Unfortunately, radiotherapy and chemotherapy are not effective at treating some cases of this disease, and the 5‐year survival rate is only 40–50%. Cell division cycle 25A (CDC25A) has been shown to induce radioresistance in a variety of tumor cells, but the role of CDC25A in the radioresistance of cervical cancer has not been fully elucidated. Here, we report that CDC25A is highly expressed and miR‐122‐5p lowly expressed in cervical cancer tissues and cells. The TargetScan database was used to predict CDC25A as a target of miR‐122‐5p, and the interactions between miR‐122‐5p and CDC25A were further confirmed by western blot, real‐time PCR and dual‐luciferase reporter assay. Under X‐ray irradiation, up‐regulation of CDC25A can promote the radiation resistance of cervical cancer cells, whereas overexpression of miR‐122‐5p or knockdown of CDC25A inhibits the survival and induces apoptosis of cervical cancer colonies. In conclusion, our data suggest that miR‐122‐5p enhances the radiosensitivity of cervical cancer cells by targeting CDC25A.

Toward early cancer detection: Focus on biosensing systems and biosensors for an anti-apoptotic protein survivin and survivin mRNA

The development of biosensors for cancer biomarkers has recently been expanding rapidly, offering promising biomedical applications of these sensors as highly sensitive, selective, and inexpensive bioanalytical tools that can provide alternative methodology to that afforded by the advanced hyphenated-instrumental techniques. In this review, we focus particularly on the detection of a member of the inhibitor of apoptosis proteins (IAP) family, protein survivin (Sur), a ubiquitous re-organizer of the cell life cycle with the ability to inhibit the apoptosis and induce an enhanced proliferation leading to the unimpeded cancer growth and metastasis. Herein, we critically evaluate the progress in the development of novel biosensing systems and biosensors for the detection of two survivin (Sur) biomarkers: the Sur protein and its messenger RNA (Sur mRNA), including immunosensors, electrochemical piezo- and impedance-sensors, electrochemi-luminescence biosensors, genosensors based on oligonucleotide molecular beacons (MBs) with fluorescent or electrochemical transduction, as well as the microfluidic and related analytical platforms based on solution chemistry. The in-situ applications of survivin biomarkers' detection technologies to equip nanocarriers of the controlled drug delivery systems with MB-based fluorescence imaging capability, apoptosis control, and mitigation of the acquired drug resistance are also presented and critically evaluated. Finally, we turn the attention to the application of biosensors for the analysis of Sur biomarkers in exosomes and circulating tumor cells for a non-invasive liquid biopsy. The prospect of a widespread screening for early cancers, based on inexpensive point-of-care testing using biosensors and multiplex biosensor arrays, as a means of reducing the high cancer fatality rate, is discussed.

High expression of survivin predicts poor prognosis in cervical squamous cell carcinoma treated with paclitaxel and carboplatin

Lack of effective biomarkers is one of the challenges in current neoadjuvant chemotherapy to predict drug response and sensitivity of cervical squamous cell carcinoma (CSCC). The present study was designed to investigate the correlation of the expression of survivin, an inhibitor of apoptosis with the prognosis of CSCC patients undergoing neoadjuvant chemotherapy.A total of 117 CSCC patients treated with paclitaxel and carboplatin between May 2015 and April 2017 in the Second Hospital of Lanzhou University were retrospectively analyzed. The pathologic diagnosis and classification of CSCC were based on the Guidelines of the International Federation of Gynaecology and Obstetrics (FIGO). The efficacy was defined as complete remission (CR), partial remission (PR), and stability disease (SD). The expressions of survivin, vascular endothelial growth factor (VEGF), and Ki67 were determined with immunohistochemistry. Data were analyzed with SPSS software.Univariate analysis showed that survivin expression had no correlation with ages, FIGO stage, macroscopic type, lymphovascular invasion, depth of lymphovascular invasion, lymph node metastasis, and tumor size among 117 CSCC patients. However, survivin expression was positively correlated with pathological grade (R = 0.691, P < .001). Multivariate analysis revealed that survivin expression was independently correlated with grades (P < .001). In addition, the analysis of correlation indicated that survivin expression is positively correlated with VEGF expression (R = 0.820, P < .001) and Ki67 expression (R = 0.673, P < .001). The numbers (percentages) of complete remission (CR), partial remission (PR), and stability disease (SD) were 11 (9.4%), 91 (77.8%), and 15 (12.8%) respectively after the treatment of paclitaxel and carboplatin. Univariate analysis showed that efficacy of treatment was negatively correlated with pathological grade (R = 0.513, P < .001), Ki67 expression (R = 0.586, P < .001), VEGF expression (R = 0.476, P < .001) and survivin expression (R = 0.519, P < .001). Multivariate analysis revealed that efficacy of treatment was independently correlated with grades (P = .028), Ki67 (P < .001), and survivin expression (P = .015).The results suggested that survivin expression is negatively correlated with the prognosis of CSCC patients treated with paclitaxel and carboplatin. Therefore, survivin expression might be a marker for prognosis in CSCC following neoadjuvant chemotherapy.

In vivo antitumor activity of liposome‑plasmid DNA encoding mutant survivin‑T34A in cervical cancer

The aim of the present study was to investigate the influence of liposome-plasmid encoding mutant survivin-T34A (PST34A) on tumor growth in cervical cancer in vivo. Liposome-plasmid DNA encoding mutant survivin-T34A was constructed and administered via an intraperitoneal injection in mice inoculated with cervical cancer cells. Following the establishment of the tumor model, the animals were randomly divided into four groups: i) The normal saline group (NS; 100 µl sterile saline once/3 days for 15 days); ii) the 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) control (100 µg DOTAP once/3 days for 15 days); iii) the plasmid PST34A (10 µg PST34A once/3 days for 15 days); and iv) the PST34A+DOTAP (10 µg PST34A+100 µg DOTAP once/3 days for 15 days). All treatments were administered via intraperitoneal injections. Tumor growth was evaluated following injection with liposome-plasmid DNA encoding mutant survivin-T34A. Apoptosis of cells in ascitic fluid was detected by flow cytometry. The expression of Ki67 and CD34 was detected by immunohistochemical staining. Administration of liposome-plasmid complexes encoding mutant survivin-T34A inhibited tumor growth, reduced the number of tumor nodules and the volume of ascitic fluid, and decreased abdomen circumference and tumor weight. The number of Ki67-positive cells was markedly reduced in the DOTAP+PST34A group compared with the remaining groups. Flow cytometry demonstrated that the number of cells in the sub-G1 phase (apoptosis) increased in the DOTAP+PST34A group compared with all other groups. In addition, tumors in the DOTAP+PST34A group exhibited lower microvessel density compared with all other groups. In the present study, liposome-plasmid DNA encoding mutant survivin-T34A could inhibit tumor growth of cervical cancer. This inhibition may be associated with an increase in the apoptosis rate of tumor cells and a reduction in angiogenesis.

Honokiol Radiosensitizes Squamous Cell Carcinoma of the Head and Neck by Downregulation of Survivin

Purpose: Previous studies revealed diverging results regarding the role of survivin in squamous cell carcinoma of the head and neck (SCCHN). This study aimed to evaluate the clinical significance of survivin expression in SCCHN; the function of survivin in DNA-damage repair following ionizing radiation therapy (RT) in SCCHN cells; and the potential of honokiol to enhance RT through downregulation of survivin.Experimental Design: Expression of survivin in SCCHN patient primary tumor tissues (n = 100) was analyzed and correlated with clinical parameters. SCCHN cell lines were used to evaluate the function of survivin and the effects of honokiol on survivin expression in vitro and in vivoResults: Overexpression of survivin was significantly associated with lymph nodes' metastatic status (P = 0.025), worse overall survival (OS), and disease-free survival (DFS) in patients receiving RT (n = 65, OS: P = 0.024, DFS: P = 0.006) and in all patients with SCCHN (n = 100, OS: P = 0.002, DFS: P = 0.003). In SCCHN cells, depletion of survivin led to increased DNA damage and cell death following RT, whereas overexpression of survivin increased clonogenic survival. RT induced nuclear accumulation of survivin and its molecular interaction with γ-H2AX and DNA-PKCs. Survivin specifically bound to DNA DSB sites induced by I-SceI endonuclease. Honokiol (which downregulates survivin expression) in combination with RT significantly augmented cytotoxicity in SCCHN cells with acquired radioresistance and inhibited growth in SCCHN xenograft tumors.Conclusions: Survivin is a negative prognostic factor and is involved in DNA-damage repair induced by RT. Targeting survivin using honokiol in combination with RT may provide novel therapeutic opportunities. Clin Cancer Res; 24(4); 858-69. ©2017 AACR.