Cancer In Southern China Research Articles

Identification of sequence polymorphism in the D-loop region of mitochondrial DNA as a risk factor for breast cancer.

Mitochondrial DNA (mtDNA) variations affect the efficiency of the electron transport chain and production of reactive oxygen species, contributing to carcinogenesis. The D-loop region of mtDNA has emerged as a variation hotspot region in human neoplasia; however, the potential contribution of these variations in breast cancer risk prediction remains unknown. We investigated the relationship between germline single nucleotide polymorphisms (SNPs) in the entire D-loop region and breast cancer risk in Chinese women. Peripheral blood-isolated mtDNA from 2329 patients with breast cancer and 2328 cancer-free controls was examined for SNPs. In the combined cohort, we used traditional risk factors, susceptibility germline polymorphisms, and logistic regression analysis to evaluate the predictive value of susceptibility variants for breast cancer risk. We calculated the area under the receiver operating characteristic curve (AUC) as a measure. We also measured the content of 8-hydroxy-2'-deoxyguanosine (8-OHdG). Individual polymorphisms SNP573 were significantly associated with breast cancer risk in both the discovery and validation cohorts. In the combined cohort, the AUC of the traditional risk factors was 64.3%; after adding susceptibility variants, the AUC was 64.9% (DeLong test, p = 0.007). 8-OHdG levels were significantly higher in patients with breast cancer than in controls and higher in individuals with SNP573 than in those negative for this variation. Overall, oxidative stress might be associated with the risk of breast cancer, and SNP573 might be associated with oxidative stress. Our results indicate the risk potential of polymorphisms in the D-loop region in breast cancer in Southern China.

Urban residential greenness and cancer mortality: Evaluating the causal mediation role of air pollution in a large cohort

Evidence linking greenness to all-site and site-specific cancers remains limited, and the complex role of air pollution in this pathway is unclear. We aimed to fill these gaps by using a large cohort in southern China. A total of 654,115 individuals were recruited from 2009 to 2015 and followed-up until December 2020. We calculated the normalized difference vegetation index (NDVI) in a 500-m buffer around the participants’ residences to represent the greenness exposure. Cox proportional-hazards models were used to evaluate the impact of greenness on the risk of all-site and site-specific cancer mortality. Additionally, we assessed both the mediation and interaction roles of air pollution (i.e., PM2.5, PM10, and NO2) in the greenness–cancer association through a causal mediation analysis using a four-way decomposition method. Among the 577,643 participants, 10,088 cancer deaths were recorded. We found a 10% (95% CI: 5–16%) reduction in all-site cancer mortality when the NDVI increased from the lowest to the highest quartile. When stratified by cancer type, our estimates suggested 18% (95% CI: 8–27%) and 51% (95% CI: 16–71%) reductions in mortality due to respiratory system cancer and brain and nervous system cancer, respectively. For the above protective effect, a large proportion could be explained by the mediation (all-site cancer: 1.0–27.7%; respiratory system cancer: 1.2–32.3%; brain and nervous system cancer: 3.6–109.1%) and negative interaction (all-site cancer: 2.1–25.7%; respiratory system cancer: 2.0–25.7%; brain and nervous system cancer: not significant) effects of air pollution. We found that particulate matter (i.e., PM2.5 and PM10) had a stronger causal mediation effect (25.0–109.1%) than NO2 (1.0–3.6%), while NO2 had a stronger interaction effect (25.7%) than particulate matter (2.0–2.8%). In summary, greenness was significantly beneficial in reducing the mortality of all-site, respiratory system, and brain and nervous system cancer in southern China, with the impact being modulated and mediated by air pollution.

Role of Peroxiredoxin 1 Induced by Epstein-Barr Virus Infection in Nasopharyngeal Carcinoma.

Nasopharyngeal carcinoma (NPC), a common cancer in Southern China, is associated with Epstein-Barr Virus (EBV) infection. Although many therapies for NPC have been established, the definite role of EBV in NPC remains unclear. Therefore, this work focuses on LMP2A, a latent EBV gene, and investigates whether LMP2A is related to peroxiredoxin 1 (PRDX1) in EBV-positive NPC. The mRNA and protein expression levels of LMP2A, PRDX1, and beta-catenin were compared in patient samples. To identify molecular mechanisms, EBV-negative NP69 and EBV-positive C666-1 NPC cell lines were used. After making an agar cell block for cell slides, the intensity of LMP2A expression was observed visually. To measure the level of reactive oxygen species, both fluorescence microscope and flow cytometry were used. To investigate the intracellular signaling molecular mechanisms with and without the LMP2A gene, reverse transcription polymerase chain reaction and western blotting were used. Both patient samples and cells of nasopharyngeal carcinoma infected with EBV had increased expression of LMP2A compared with controls, and high ROS levels were identified. Cell viability assay showed that LMP2A promoted cell growth by regulating gene expression. Furthermore, LMP2A induced the expression of PRDX1 and beta-catenin. LMP2A also increased the expression of both cyclin B1 and cyclin D1. In NPC cells, PRDX1 and beta-catenin were regulated through LMP2A expression, which reduced cell growth through cell cycle-related gene expression. This study suggests that LMP2A could be a target molecule for inhibiting cancer progression in NPC cells infected with EBV.

Regional lymph node density-based nomogram predicts prognosis in nasopharyngeal carcinoma patients without distant metastases

BackgroundNasopharyngeal carcinoma (NPC) is a relatively common type of cancer in Southern China, with local recurrence or distant metastases even after radical treatment; consequently, it is critical to identify the patients at higher risk for these events beforehand. This study aimed to assess the prognostic value of regional lymph node density (RLND) associated nomograms in NPC and to evaluate the utility of nomograms in risk stratification.MethodsA total of 610 NPC patients without distant metastases (425 in the training and 185 in the validation cohort) were enrolled. The MRI-identified nodal features and clinical characteristics were documented, and the RLND was calculated. Cox analyses were conducted to identify prognostic-associated factors. Nomograms were generated based on the multivariate analysis results. The predictive accuracy and discriminative ability of the nomogram models were determined using the concordance index (C-index), receiver operating characteristic (ROC) curve, and calibration curve; the results were compared with those of the tumor-node-metastasis (TNM) classification. Decision curve analysis (DCA) and C-index were used to assess the prognostic effect and added discriminative ability of RLND. We also estimated the optimal RLND-based nomogram score cut-off values for survival prediction.ResultsRLND was an independent predictor of overall survival (OS) and disease-free survival (DFS), with hazard ratios of 1.36 and 1.30, respectively. RLND was utilized in the construction of nomograms, alongside other independent prognostic factors. The RLND-based nomogram models presented a more effective discriminative ability than the TNM classification for predicting OS (C-index, 0.711 vs. 0.680) and DFS (C-index, 0.681 vs. 0.669), with favorable calibration and consistency. The comparison of C-index values between the nomogram models with and without RLND provided substantiation of the crucial role RLND plays in these models. DCA confirmed the satisfactory clinical practicability of RLND. Moreover, the nomograms were used to categorize the patients into three groups (high-, middle-, and low-risk), and the Kaplan–Meier curves showed significant differences in prognosis between them (p < 0.05). These results were verified in the validation cohort.ConclusionRLND stands as a robust prognostic factor in NPC. The RLND-based nomograms excel in predicting survival, surpassing the TNM classification.

Preliminary Validation of the Revised Illness Perception Questionnaire for Patients with Nasopharyngeal Carcinoma in China.

Nasopharyngeal carcinoma is a common and highly malignant cancer in southern China. It is important to accurately assess the illness perception of nasopharyngeal carcinoma according to the common-sense model of self-regulation. The purpose was to validate the Chinese version of the Revised Illness Perception Questionnaire for patients with Nasopharyngeal carcinoma. A cross-sectional survey of 631 patients with Nasopharyngeal carcinoma was conducted in Guangzhou, China. The reliability of the scale was evaluated using Cronbach's alpha. The factor structure was assessed using exploratory factor analysis (EFA) of each dimension. The EFA revealed that the 29-item self-rated scale has a seven-factor structure consistent with the original scale and explained 67.3% of the variance after extraction and rotation. The scale showed satisfactory reliability. The item-total correlations ranged from -0.16 to 0.64 (p < 0.05). The item-subscale correlations ranged from 0.46 to 0.91 (p < 0.05). The item-other subscale correlations ranged from -0.38 to 0.51 and from -0.21 to 0.56 (p < 0.05). Significant correlations were found between the timeline (acute/chronic) (r = 0.224, r = 0.166), consequences (r = 0.415, r = 0.338), timeline cyclical (r = 0.366, r = 0.284), emotional representations (r = 0.497, r = 0.465), personal control (r = -0.122, r = -0.134), treatment control (r = -0.135, r = -0.148), and illness coherence (r = -0.261, r = -0.213) subscales, and depression, anxiety (p < 0.05). The scale revealed acceptable reliability, factorial validity, and construct validity. It could be used to assess the illness representations of Chinese patients with nasopharyngeal carcinoma.

TOM40 regulates the progression of nasopharyngeal carcinoma through ROS-mediated AKT/mTOR and p53 signaling

Nasopharyngeal carcinoma (NPC) is a prevalent cancer in Southern China, North Africa, and Southeast Asia. The translocase of the outer membrane (TOM) 40 is a transporter of mitochondrial proteins, and is involved in ovarian cancer cell growth. However, its role in the progression of NPC is still unclear. We found that TOM40 levels were upregulated in NPC tissues and multiple NPC cell lines. In addition, high TOM40 expression in the tumor tissues was associated with poor overall survival and disease specific survival. TOM40 knockdown in the NPC cell lines inhibited their proliferation in vitro and in vivo. Furthermore, TOM40 silencing also increased intracellular production of reactive oxygen species (ROS) and decreased mitochondrial membrane potential (MMP). Mechanistically, the anti-tumor effects of TOM40 silencing were dependent on the inhibition of AKT/mTOR signaling and activation of p53 signaling. To summarize, TOM40 mediates NPC progression through ROS-mediated AKT/mTOR and p53 signaling. Our findings highlight the potential of TOM40 as a therapeutic target for NPC.

Abstract 4912: Anticancer activity of Hsp90 inhibitor AUY922 in nasopharyngeal carcinoma and non-small cell lung cancer cells

Abstract Introduction: Nasopharyngeal carcinoma (NPC) and non-small cell lung cancer (NSCLC) are two of the most prevalent cancers in Southern China. Although cisplatin therapy may be initially successful, its effectiveness is often significantly reduced in patients with relapsed disease. There is an urgent need to overcome cisplatin resistance in the treatment of NPC and NSCLC. Luminespib (AUY922) is an experimental drug candidate for the treatment of cancer. It is an inhibitor of heat shock protein 90 (Hsp90), a chaperone protein that plays a role in modifying a variety of proteins involved in tumorigenesis. Hsp90 inhibitors have demonstrated potent activity in preclinical testing and clinical trials against various cancer types. We sought to investigate the preclinical efficacy of AUY922 and evaluate its anticancer effect in cisplatin-resistant NPC and NSCLC cells. Materials and Methods: Two NPC cells (HK1 and Hone1), four NSCLC cells (A549, SW900, NCI-H1975, and HCC4006), one normal lung cells (CCD11Lu), two cisplatin-resistant NPC cells (HK1-R and Hone1-R), and one cisplatin-resistant NSCLC cells (A549-R) were cultured and treated with 100 nM AUY922 for 48 hours. A cell proliferation assay was performed in triplicate to determine the antiproliferative effects of AUY922 on cancer cells. Flow cytometry was used for cell cycle analysis. The apoptotic cells were evaluated by Annexin V and Western blot analysis. Nude mice were used to test the effects of intraperitoneal injection of AUY922 on tumor growth. Results: We found that AUY922 significantly inhibited in vitro growth in all the two NPC (44% and 40%) and four NSCLC (53%, 77%, 50%, and 62%) cells in comparison to the normal lung cells (4%). The two cisplatin-resistant NPC cells (63% and 37%) also showed significant inhibition of viability after treatment with AUY922. However, there was only a slightly reduced viability in the cisplatin-resistant NSCLC cells (14%). Flow cytometry revealed that AUY922 induced G2/M and S phase arrest in HK1 and HK1-R cells. On the other hand, AUY922 also induced pro-apoptotic peaks in A549, A549-R, Hone1, and Hone1-R cells. Interestingly, Annexin V and Western blot analysis showed that cell death was not caused by apoptosis. In vivo, both AUY922 alone and the combination of AUY922 with cisplatin treatments inhibited NPC and NSCLC tumor growth without significant weight loss. In addition, the administration of AUY922 significantly reduced NPC and NSCLC tumor growth in the cisplatin-resistant mouse models. Conclusion: AUY922 exhibits potent anticancer activities in vitro and in vivo. These findings provide evidence that AUY922 could be useful for the treatment of NPC and NSCLC as a single agent or in combination with cisplatin. Most importantly, our results provide a preclinical proof of concept for the efficacy of AUY922 in cisplatin-resistant NPC and NSCLC treatment. Citation Format: William C. Cho, Chi F. Wong. Anticancer activity of Hsp90 inhibitor AUY922 in nasopharyngeal carcinoma and non-small cell lung cancer cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4912.

A retrospective study on sperm cryopreservation in 1034 patients diagnosed with cancer in southern China.

Sperm cryopreservation is an effective fertility preservation method for cancer patients before anticancer treatments. However, there are little data on fertility preservation in large cohorts of patients with cancer in southern China. This retrospective cross-sectional study aimed to assess the fertility preservation status of 1034 newly diagnosed male patients with cancer in the Human Sperm Bank of Guangdong Province in southern China (Guangzhou, China). Of these, 302 patients had reproductive system tumors, mostly testicular cancers (99.0%), and 732 had other tumors, including lymphoma (33.1%), gastrointestinal cancer (16.3%), nasopharyngeal carcinoma (15.7%), leukemia (7.7%), sarcoma (3.6%), and others (23.6%). Patients with reproductive system tumors had lower sperm concentration and prefreezing and post-thawing progressive motility than those with non-reproductive system tumors (all P < 0.001). Differences in sperm concentration, progressive motility, and normal morphology rate were observed between patients with and without anticancer surgery before sperm cryopreservation (all P < 0.05). As of April 30, 2022, 63 patients used their cryopreserved sperm for assisted reproductive technology treatments and 39 pregnancies were achieved. This study provides valuable data on the fertility preservation status in newly diagnosed cancer patients in southern China, demonstrating that patients with reproductive system tumors had poor sperm quality for their pretreatment fertility preservation.

A novel oncogenic seRNA promotes nasopharyngeal carcinoma metastasis

Nasopharyngeal carcinoma (NPC) is a common malignant cancer in southern China that has highly invasive and metastatic features and causes high mortality, but the underlying mechanisms of this malignancy remain unclear. In this study, we utilized ChIP-Seq to identify metastasis-specific super enhancers (SEs) and found that the SE of LOC100506178 existed only in metastatic NPC cells and powerfully aggravated NPC metastasis. This metastatic SE transcribed into lncRNA LOC100506178, and it was verified as a seRNA through GRO-Seq. Furthermore, SE-derived seRNA LOC100506178 was found to be highly expressed in metastatic NPC cells and NPC lymph node metastatic tissues. Knockdown of seRNA LOC100506178 arrested the invasion and metastasis of NPC cells in vitro and in vivo, demonstrating that seRNA LOC100506178 accelerates the acquisition of NPC malignant phenotype. Mechanistic studies revealed that seRNA LOC100506178 specifically interacted with the transcription factor hnRNPK and modulated the expression of hnRNPK. Further, hnRNPK in combination with the promoter region of MICAL2 increased Mical2 transcription. Knockdown of seRNA LOC100506178 or hnRNPK markedly repressed MICAL2, Vimentin and Snail expression and upregulated E-cadherin expression. Overexpression of seRNA LOC100506178 or hnRNPK markedly increased MICAL2, Vimentin and Snail expression and decreased E-cadherin expression. Therefore, seRNA LOC100506178 may promote MICAL2 expression by upregulating hnRNPK, subsequently enhancing EMT process and accelerating the invasion and metastasis of NPC cells. seRNA LOC100506178 has the potential to serve as a novel prognostic biomarker and therapeutic target in NPC patients.

Bacterial spectrum analysis and antimicrobial susceptibility study of osteoradionecrosis of the jaw in Southern China

Osteoradionecrosis of the jaw (ORNJ) is one of the most common and serious complications after radiotherapy of head and neck malignancies due to the high incidence of nasopharyngeal cancer in Southern China. Clinicians lack understanding and consensus on anti-infective treatment in ORNJ lesions. This research aims to provide evidence for rational use of antibiotics by reviewing the bacterial spectrums and antimicrobial susceptibility test of ORNJ patients. We collected patient who was diagnosed with ORNJ from November 2012 to June 2019 in our hospital. Exudate or bone unexposed wound surface sampling, agar plates culturing, and susceptibility testing were analyzed. Descriptive statistics were used for data presentation. A total of 219samples were collected in our retrospective study. The most common cultured bacteria were Klebsiella pneumoniae (15.10%), Pseudomonas aeruginosa (13.54%), and Staphylococcus aureus (10.94%). Methicillin-resistant Staphylococcus aureus (MRSA) accounted for 5.21% in the whole positive samples. Ticarcillin, Ofloxacin, Vancomycin, Tigecycline, and Meropenem were more susceptible than other antibiotics to treat uncontrollable infection. Our research provided objective evidence for understanding the types of local bacterial flora and drug susceptibility in ORNJ lesions and gave a guiding reference for empirical antibiotics medication.

Analysis of the Differentially Expressed Genes and microRNAs and Prediction of miRNA-mRNA negative Regulatory Network in Nasopharyngeal Carcinoma

Introduction: Nasopharyngeal carcinoma (NPC) is an endemic cancer in southern China, particularly in Guangdong population, but the prognosis of NPC is poor. Recently microRNA (miR) has been shown to have function in aiding the treatment of cancer. Thus, in this study, miRNAs and genes associated with NPC were analyzed. Methods: mRNA-sequencing and miR-sequencing data were obtained from the Gene Expression Omnibus. The differentially expressed genes (DEGs) and miRNAs (DEMs) were filter out. Then, the gene function annotations about the DEGs were predicted using Gene Ontology (GO) and KEGG pathway. Subsequently, the protein-protein interaction (PPI) network was established based on the STRING database, and function modules were identified using Cytoscape. Finally, DEGs targeted by DEMs were predicted by using the miRDB, miRTarBase, TargetScan and DIANA databases, and the DEM-DEG negative interaction network was built. Results: In all, 704 DEGs (about 49.9% upregulated) were enriched in 234 GO terms and 53 KEGG pathways. Seven hub genes (APP, GNG2, VAV1, RAC2, YES1, EGFR and GNB5) in 6 function modules were found for the PPI network. In addition, 86 DEMs were identified containing 56 upregulated and 30 downregulated miRNAs. There were 538 DEM-DEG pairs, of which miR-93-5p/TGFBR2, miR-455-3p/STK17B and miR-766-5p/ITGAV had functions in other cancers, moreover, these pairs may potentially contributed to NPC pathogenesis. Conclusion: The constructed miRNA-mRNA negetive regulatory network will give help in elucidating the molecular mechanisms of NPC. The important DEGs, DEMs and DEM-DEG pairs associated with NPC may contribute to the diagnosis and treatment of NPC in the future.

Spatial and Temporal Analysis of Lung Cancer in Shenzhen, 2008-2018.

Lung cancer is the most commonly diagnosed cancer in China. The incidence trend and geographical distribution of lung cancer in southern China have not been reported. The present study explored the temporal trend and spatial distribution of lung cancer incidence in Shenzhen from 2008 to 2018. The lung cancer incidence data were obtained from the registered population in the Shenzhen Cancer Registry System between 2008 and 2018. The standardized incidence rates of lung cancer were analyzed by using the joinpoint regression model. The Moran’s I method was used for spatial autocorrelation analysis and to further draw a spatial cluster map in Shenzhen. From 2008 to 2018, the average crude incidence rate of lung cancer was 27.1 (1/100,000), with an annual percentage change of 2.7% (p < 0.05). The largest average proportion of histological type of lung cancer was determined as adenocarcinoma (69.1%), and an increasing trend was observed in females, with an average annual percentage change of 14.7%. The spatial autocorrelation analysis indicated some sites in Shenzhen as a high incidence rate spatial clustering area. Understanding the incidence patterns of lung cancer is useful for monitoring and prevention.

Polyethylene Glycol-Coated Graphene Oxide Loaded with Erlotinib as an Effective Therapeutic Agent for Treating Nasopharyngeal Cancer Cells.

IntroductionNasopharyngeal carcinoma (NPC) is a common cancer in southern China and Taiwan, and radiation therapy combined with or without chemotherapy is its mainstay treatment. Although it is highly sensitive to radiotherapy, local recurrence and distant metastasis remain difficult unsolved problems. In recent years, graphene oxide (GO) has been found to be a promising novel anticancer drug carrier. Here, we present our designed functionalized GO, polyethylene glycol-coated GO (GO-PEG), as a drug carrier, which was loaded with erlotinib and showed promising anticancer effects on NPC cells.MethodsThe effects of GO-PEG-erlotinib on the proliferation, migration, and invasion of NPC cells were investigated by WST-8 assay, wound healing assay, and invasion assay, respectively. RNA sequencing was conducted and analyzed to determine the molecular mechanisms by which GO-PEG-erlotinib affects NPC cells.ResultsOur results showed that GO-PEG-erlotinib reduced NPC cell viability in a dose-dependent manner and also inhibited the migration and invasion of NPC cells. The RNA sequencing revealed several related molecular mechanisms.ConclusionGO-PEG-erlotinib effectively suppressed NPC cell proliferation, migration, and invasion, likely by several mechanisms. GO-PEG-erlotinib may be a potential therapeutic agent for treating NPC in the future.

BIX-01294-enhanced chemosensitivity in nasopharyngeal carcinoma depends on autophagy-induced pyroptosis.

Nasopharyngeal carcinoma (NPC) is a common cancer in southern China and Southeast Asia. Nowadays, radiotherapy is the therapy of choice for NPC patients, and chemotherapy has been found as an alternative treatment for advanced NPC patients. However, finding novel drugs and pharmacologically therapeutic targets for NPC patients is still urgent and beneficial. Our study showed that BIX-01294 (BIX) can induce autophagic vacuoles formation and conversion of LC3B-I to LC3B-II in NPC cells in both dose- and time-dependent manners. Notably, the combination of BIX and chemotherapeutic drugs significantly decreased the cell viability and increased the lactate dehydrogenase release. Meanwhile, BIX plus cis-platinum (Cis) treatment induced pyroptosis in NPC cells as featured by cell swelling and bubble blowing from the plasma membrane, the increased frequency of annexin V and propidium iodide (PI) double-positive cells, as well as the cleavage of gasdermin E (GSDME) and caspase-3. Moreover, the deficiency of GSDME completely shifted pyroptosis to apoptosis. Furthermore, the inhibition of autophagy by chloroquine and the knockout of ATG5 gene significantly blocked the BIX-induced autophagy as well as pyroptosis in both in vitro and in vivo studies. Our data demonstrated that BIX-combined chemotherapeutic drugs could induce the Bax/caspase-3/GSDME-mediated pyroptosis through the activation of autophagy to enhance the chemosensitivity in NPC.

Dietary Inflammatory Index and Epithelial Ovarian Cancer in Southern Chinese Women: A Case-Control Study.

The association between inflammatory properties of diet and ovarian cancer risk has been investigated in some Western populations. However, little evidence is available from Asian women whose ovarian cancer incidence rates are low and dietary and lifestyle patterns are very different from their Western counterparts. We aimed to examine whether more pro-inflammatory diets, as indicated by higher dietary inflammatory index (DII®) scores, are associated with increased odds of epithelial ovarian cancer in southern China. A case-control study was conducted during 2006-2008 in Guangzhou, Guangdong Province. Energy-adjusted DII (E-DII) scores were calculated based on dietary intake assessed by a validated food frequency questionnaire administered to 500 incident epithelial ovarian cancer patients and 500 hospital-based controls. Logistic regression models were used to assess the relationship between E-DII scores and odds of ovarian cancer. Positive associations were observed between higher E-DII scores and ovarian cancer odds, using both continuous DII scores (odds ratio (OR) 1.87; 95% confidence interval (CI) 1.65, 2.13) and by DII tertiles (ORtertile3vs1 7.04, 95% CI: 4.70, 10.54, p for trend < 0.001). Likewise, a more pro-inflammatory diet was associated with a higher chance of serous and mucinous ovarian tumors. Our results suggest that a pro-inflammatory diet was associated with increased odds of developing epithelial ovarian cancer in southern Chinese women. The findings add to epidemiological evidence for the role of dietary inflammatory potential in ovarian cancer development.

Saliva electrolyte analysis and xerostomia-related quality of life in nasopharyngeal carcinoma patients following intensity-modulated radiation therapy

Background and purposeNasopharyngeal carcinoma (NPC) is one of the most common cancers in southern China and the first-line treatment is radiotherapy. Intensity-modulated radiation therapy (IMRT) can deliver high dose to cancer and low dose to normal tissue, but xerostomia is still one of the complications after IMRT. However, how the concentration of saliva electrolytes be affected by IMRT and the effects on the quality of life are still unknown. In this prospective study, 76 NPC patients were recruited from hospitals in Hong Kong to identify the change of saliva electrolytes and xerostomia-related quality of life before and after IMRT. Methods and materialsSaliva and questionnaire were collected before IMRT, 1 month, 3 months, 6 months and 12 months after IMRT. The concentration of saliva electrolytes was detected using inductively coupled plasma-optical emission spectroscopy (ICP-OES). ResultsSaliva flow rate significantly decreased after IMRT. Decrease in the mean value of pH was observed but the difference is not statistically significant. The concentrations of potassium, iodine, and calcium decreased and chloride concentration increased after IMRT, while the concentrations of sodium, magnesium, copper or zinc were kept at the same level before and after treatment. Xerostomia-related quality of life was adversely affected by IMRT, but partially recovered after 1 year. ConclusionsOur study revealed the change of saliva electrolytes and xerostomia-related quality of life in patients undergone IMRT for NPC.

Young onset breast cancer in Southern China – a 5-year clinico-pathological study from a multi-centre database

AimsBreast cancer onset is known to be younger in China when compared to many westernized countries, the reason remains unknown. This study aims to evaluate the clinical and pathological characteristics of young breast cancer in Hong Kong and Shenzhen, China. MethodsThis is a 5-year retrospective review of a prospectively-maintained region-wide database. Patients treated in Hong Kong and Shenzhen between 2013 and 2017 were analysed. Results1610 breast cancer patients were identified for analysis, 1108 patients were from Hong Kong and 502 patients were from Shenzhen. Median age of breast cancer onset was 60 years old in Hong Kong (Range 21 – 103), while that in Shenzhen was 46 years old (Range 23 – 85). 59 (5.3%) patients from the Hong Kong cohort were younger than 40 years old at the age of diagnosis (i.e. young breast cancer), comparing to 152 (30.3%) patients from the Shenzhen cohort (p < 0.0001).There were more nulliparity, positive family history and use of exogenous hormones in young breast cancer patients in Hong Kong (p = 0.0043, < 0.0001 and 0.0022). Pathological characteristics were however comparable between the two cohorts, apart from being more triple negative breast cancers in young breast cancer patients in Hong Kong (p = 0.05). ConclusionAge of onset of breast cancer tends to be younger in mainland China than in Hong Kong. Personal and familial risk factors were not significantly different. Environmental factor may play an important role.

&lt;p&gt;Amyloid Beta (A4) Precursor Protein: A Potential Biomarker for Recurrent Nasopharyngeal Carcinoma&lt;/p&gt;

Background and AimNasopharyngeal carcinoma (NPC) is one of the most common cancers in Southern China, Southeast Asia. Radiotherapy is the main treatment for NPC. Still, about 20% of patients with NPC have a recurrence. No effective serum biomarkers are available for recurrent nasopharyngeal carcinoma (rNPC) to date. This study aimed to explore whether amyloid beta (A4) precursor protein (APP) might serve as a valuable diagnostic and prognostic biomarker for patients with rNPC.MethodsIn a previous study, a tandem mass tag–based proteomic test was performed, which screened 59 differentially expressed proteins (DEPs) between nonrecurrent nasopharyngeal carcinoma (nrNPC) and rNPC. In this study, a protein–protein interaction was conducted to screen the key proteins among the 59 DEPs. APP was validated and evaluated by enzyme-linked immunosorbent assay in 70 serum samples [recurrence (n = 35) and no-recurrence (n = 35)]. Also, the receiver operating characteristic (ROC) curve was plotted to evaluate the predictive value of APP.ResultsThe area under the ROC curve was 0.666 (95% CI: 0.514–0.818, P = 0.044). The best cutoff point of the relative expression levels for APP was 1.23 (concentration = 16.95 ng/mL), at which the sensitivity was 55.2% and the specificity was 90.9%.ConclusionThe findings indicated that APP might be a valuable diagnostic and prognostic biomarker for patients with rNPC.

Abstract 5142: New genomic alterations are frequently detected in recurrent nasopharyngeal carcinoma compared with the primary tumors

Abstract Introduction: Nasopharyngeal carcinoma (NPC) is a common cancer in Southern China and Southeast Asia. The clinical outcomes of patients with early stage disease have improved significantly in recent years, but a substantial number of patients would develop recurrent disease and it is the major cause of mortality. Understanding the genetic mechanism of relapse may help develop novel treatment modalities and strategies for this group of patients. This study aims to compare and identify the genetic alterations in primary and recurrent NPC by next-generation sequencing. Materials and Methods: The archived paired samples of 7 primary and 8 matched relapsed tumor tissues from seven NPC patients (one with 2 relapsed points) who developed recurrence after treatment were retrieved. Using deep targeted next-generation sequencing, we evaluated a panel of 440 genes in these 15 NPC samples. Genomic alterations found in cancer samples at the first diagnosis (primary tumors) were compared with those found in the relapsed tissues (progression after treatment). Results: Overall, we found that all patients showed a number of mutations in both the primary tumors and relapsed tissues. The most frequently mutated genes were MUC16 (85.7%), ADAMTS9 (80%), MITF (73.3%), ADAMTSL1 (73.3%), PTPRD (66.7%), TEK (66.7%), FOXP1 (53.3%) and IRS2 (53.3%). We observed that MCL1(42.9%), SOX2 (42.9%) and PIK3C2G (28.6%) mutations were only found in the primary tumor. Comparing to the primary tumors, all patients acquired new mutations in the relapsed tissues. The seven patients have each acquired 6, 13, 14, 20, 29, 31 and 35 new genomic alterations respectively. PAX5 (42.9%), PIK3CA (42.9%), CREBBP (28.6%), DPYD (28.6%), FANCG (28.6%), BIRC2 (28.6%), BIRC3 (28.6%) and PTEN (28.6%) were the most frequently detected gene mutations newly acquired in the relapsed tissues. Conclusion: This study demonstrated that mutation events might be present at diagnosis or arise during cancer treatment. The finding that all primary tumors harboring a number of mutations could explain the subsequent relapse and might therefore warrant more precise therapies. Tumor relapse is associated with the acquisition of additional gene mutations, particularly copy number variant deletion in PAX5 gene and single nucleotide variant missense in PIK3CA gene. Our results revealed substantial discordances between the primary tumors and recurrences, stressing the need for analysis of the relapsed tissues. Further analysis of these mutations and the study of their downstream protein may be useful for the development of novel treatment for this group of patients. Citation Format: William C. Cho, Yi-Ting Yang, Kein T. Tan, Victor W. Ma, Wah Cheuk, Roger K. Ngan, Shu-Jen Chen. New genomic alterations are frequently detected in recurrent nasopharyngeal carcinoma compared with the primary tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5142.

Inhibitory effect of simvastatin in nasopharyngeal carcinoma cells.

Nasopharyngeal carcinoma (NPC) is one of the most common malignant head and neck cancers in southern China. Although the local and regional control of NPC has been considerably improved, patients with advanced disease still suffer from poor prognosis. Statins inhibit the mevalonate pathway and play antiproliferative and proapoptotic roles in a number of cancer cells. However, the effects and molecular mechanism of statins in NPC treatment remain unclear. In this study, the cell viability of NPC cell line, C666-1, after simvastatin exposure was determined using the alamarBlue Cell Viability Assay. Cell apoptosis in C666-1 treated with simvastatin was assessed by flow cytometry and TUNEL assay. The expression levels of cell cycle regulatory proteins were determined using western blotting. Simvastatin markedly decreased cell viability in a concentration-dependent manner, increased caspase 3 activity and induced apoptosis in C666-1 cells. Simvastatin induced Bim expression by regulating phosphorylation of transcriptional factor c-Jun. Simvastatin treatment induced cell cycle arrest in the G1 phase in C666-1 cells by inhibiting the expression of cyclin D1 and cyclin-dependent kinase 4, and enhancing p27 expression. Simvastatin treatment inhibited protein kinase B and extracellular signal regulated kinase 1/2 activation. In conclusion, the results of the present study reveal the possible molecular mechanism of simvastatin-induced anti-tumor effects in C666-1 and suggest that simvastatin is a potential chemotherapy agent in NPC treatment.