Molecular mechanism of lncRNA SNHG12 in immune escape of non-small cell lung cancer through the HuR/PD-L1/USP8 axis.

BACKGROUND: The pivotal role of long noncoding RNAs (lncRNAs) in cancer immune responses has been well established. This study was conducted with the aim of exploring the molecular mechanism of lncRNA small nucleolar RNA host gene 12 (SNHG12) in immune escape of non-small cell lung cancer (NSCLC). METHODS: Expression of lncRNA SNHG12, programmed cell death receptor ligand 1 (PD-L1), ubiquitin-specific protease 8 (USP8), and human antigen R (HuR) in NSCLC tissues and cells was measured, and their binding relationship was determined. NSCLC cell proliferation and apoptosis were assessed. Peripheral blood mononuclear cells (PBMCs) were co-cultured with NSCLC cells. The ratio of CD8+ T cells, PBMC proliferation, and inflammatory factors were determined. lncRNA SNHG12 localization was assessed via subcellular fractionation assay. The half-life period of mRNA was determined using actinomycin D. Xenograft tumor models were established to confirm the role of lncRNA SNHG12 in vivo. RESULTS: LncRNA SNHG12 was found to be prominently expressed in NSCLC tissues and cells, which was associated with a poor prognosis. Silencing lncRNA SNHG12 resulted in the reduction in proliferation and the promotion of apoptosis of NSCLC cells, while simultaneously increasing PBMC proliferation and the ratio of CD8+ T cells. Mechanically, the binding of lncRNA SNHG12 to HuR improved mRNA stability and expression of PD-L1 and USP8, and USP8-mediated deubiquitination stabilized the protein level of PD-L1. Overexpression of USP8 or PD-L1 weakened the inhibition of silencing lncRNA SNHG12 on the immune escape of NSCLC. Silencing lncRNA SNHG12 restricted tumor growth and upregulated the ratio of CD8+ T cells by decreasing USP8 and PD-L1. CONCLUSION: LncRNA SNHG12 facilitated the immune escape of NSCLC by binding to HuR and increasing PD-L1 and USP8 levels.

Co-occurrence of CDKN2A/B and IFN-I homozygous deletions correlates with an immunosuppressive phenotype and poor prognosis in lung adenocarcinoma.

Homozygous deletion (HD) of CDKN2A and CDKN2B (CDKN2A/BHD ) is the most frequent copy-number variation (CNV) in lung adenocarcinoma (LUAD). CDKN2A/BHD has been associated with poor outcomes in LUAD; however, the mechanisms of its prognostic effect remain unknown. We analyzed genome, transcriptome, and clinical data from 517 patients with LUAD from the Cancer Genome Atlas (TCGA) and from 788 primary LUAD tumor and matched control samples from the MSK-IMPACT clinical cohort. CDKN2A/BHD was present in 19.1% of the TCGA-LUAD cohort and in 5.7% of the MSK-IMPACT cohort. CDKN2A/BHD patients had shorter disease-free survival and overall survival compared with CDKN2A/BWT individuals in both cohorts. Differences in clinical features did not influence the outcomes in the CDKN2A/BHD population. Mutation analyses showed that overall tumor mutational burden and mutations in classical drivers such as EGFR and RB1 were not associated with CDKN2A/BHD . In contrast, homozygous deletion of type I interferons (IFN-IHD ) frequently co-occurred with CDKN2A/BHD . CDKN2A/B and IFN-I are co-located in the same p21.3 region of chromosome 9. The co-occurrence of CDKN2A/BHD and IFN-IHD was not related to whole-genome doubling, chromosome instability, or aneuploidy. Patients with co-occurring CDKN2A/BHD and IFN-IHD had shorter disease-free survival and overall survival compared with CDKN2A/BWT patients. CDKN2A/BHD IFN-IHD had downregulated several key immune response pathways, suggesting that poor prognosis in CDKN2A/BHD LUAD could potentially be attributed to an immunosuppressive tumor microenvironment as a result of IFN-I depletion.

LPCAT1 functions as a novel prognostic molecular marker in hepatocellular carcinoma.

This study aimed to investigate the relationships between LPCAT1 expression and clinicopathologic parameters of hepatocellular carcinoma (HCC), further, to explore the effect of LPCAT1 on overall survival (OS) in patients with HCC, and its possible mechanism. Bioinformatics analysis using high throughput RNA-sequencing data from TCGA was utilized to explore the differential expression of LPCAT1 between normal and tumor tissues, and the associations between LPCAT1 expression and clinicopathological parameters. Survival analyses and subgroup survival analyses were utilized to elucidate the effect of LPCAT1 on OS in patients with HCC. Univariate analysis and multivariate analysis were used to investigate the prognostic factors. Potential LPCAT1 related tumor genes were identified by the methodology of differentially expressed genes (DEGs) screening. GO term enrichment analysis, KEGG pathway analysis and the PPI network were used to explore the potential mechanism. LPCAT1 was significantly overexpressed in HCC tumor tissues compared with normal tissues. The LPCAT1 expression was related to tumor grade, ECOG score, AFP and TNM stage, with P values of 0.000, 0.000, 0.007 and 0.000, respectively. Multivariate analysis demonstrated that LPCAT1 expression was independently associated with OS, with an HR of 1.04 (CI: 1.01-1.06, P = 0.003). The KEGG pathway enrichment analyses showed that overlapped DEGs mainly participate in the cell cycle. Finally, we identified a hub gene, CDK1, which has been reported to act on the cell cycle, consistent with the result of KEGG enrichment analysis. Collectively, these data confirmed LPCAT1 was upregulated in HCC, and was an independent predictor of the prognosis.

First-line treatment options for advanced non-small cell lung cancer patients with PD-L1 ≥ 50%: a systematic review and network meta-analysis.

INTRODUCTION: Single-agent immune checkpoint inhibitors (ICIs) like pembrolizumab or atezolizumab have been approved as first-line monotherapy for advanced non-small cell lung cancer (NSCLC) patients with PD-L1 ≥ 50%. However, emerging evidences have showed that ICI combinations (chemoimmunotherapy or dual-agent ICIs) argue to offer a higher response rate. In this network meta-analysis, we aimed to evaluate the efficacy and toxicity of first-line single-agent ICIs versus ICI combinations for advanced NSCLC patients with PD-L1 ≥ 50%. METHODS: PubMed, Embase, Cochrane Library and the Clinicaltrials.gov were systematically searched to extract eligible literature until December 2020. Outcomes included overall survival (OS), progression free survival (PFS), objective response rate (ORR) and treatment related adverse events (TRAEs) of grades 3-5. RESULTS: Fourteen studies with 3448 patients were included. The results showed that chemotherapy plus ICIs significantly improved PFS and ORR compared to chemotherapy, and sinti-chemo (HR: 0.31, 95% CI: 0.20-0.49) and pembro-chemo (OR: 4.2, 95% CI: 2.6-6.7) ranked first. In terms of OS, cemiplimab provided the best benefit versus chemotherapy (HR: 0.57, 95% CI: 0.43-0.77), followed by atezolizumab and pembro-chemo. In the subgroup analysis of histological type, pembro-chemo and sinti-chemo showed the best benefit of PFS in squamous and nonsquamous NSCLC, respectively, while there was no significant difference between ICI combinations with single-agent ICIs in OS. Moreover, the addition of chemotherapy to ICIs elevated toxicity compared to chemotherapy. CONCLUSION: The study suggested that chemotherapy plus ICIs might improve PFS and ORR than single-agent ICIs for advanced NSCLC patients with PD-L1 ≥ 50%. However, it did not lead to OS benefit.

Exercise Enhanced Cardiac Function in Mice With Radiation-Induced Heart Disease via the FNDC5/Irisin-Dependent Mitochondrial Turnover Pathway.

Background: Despite the development of radiation therapy (RT) techniques, concern regarding the serious and irreversible heart injury induced by RT has grown due to the lack of early intervention measures. Although exercise can act as an effective and economic nonpharmacologic strategy to combat fatigue and improve quality of life for cancer survivors, limited data on its application in radiation-induced heart disease (RIHD) and the underlying molecular mechanism are available. Methods: Fifteen young adult male mice were enrolled in this study and divided into 3 groups (including exercised RIHD group, sedentary RIHD group, and controls; n =5 samples/group). While the mice in the control group were kept in cages without irradiation, those in the exercised RIHD group underwent 3weeks of aerobic exercise on the treadmill after radiotherapy. At the end of the 3rd week following RT, FNDC5/irisin expression, cardiac function, aerobic fitness, cardiomyocyte apoptosis, mitochondrial function, and mitochondrial turnover in the myocardium were assessed to identify the protective role of exercise in RIHD and investigate the potential mechanism. Results: While sedentary RIHD group had impaired cardiac function and aerobic fitness than controls, the exercised RIHD mice had improved cardiac function and aerobic fitness, elevated ATP production and the mitochondrial protein content, decreased mitochondrial length, and increased formation of mitophagosomes compared with sedentary RIHD mice. These changes were accompanied by the elevated expression of FNDC5/irisin, a fission marker (DRP1) and mitophagy markers (PINK1 and LC3B) in exercised RIHD group than that of sedentary RIHD group, but the expression of biogenesis (TFAM) and fusion (MFN2) markers was not significantly changed. Conclusion: Exercise could enhance cardiac function and aerobic fitness in RIHD mice partly through an autocrine mechanism via FNDC5/irisin, in which autophagy was selectively activated, suggesting that FNDC5/irisin may act as an intervening target to prevent the development of RIHD.

PMEPA1 facilitates non-small cell lung cancer progression via activating the JNK signaling pathway.

BACKGROUND: Prostate transmembrane protein androgen-induced 1 (PMEPA1), a critical checkpoint of multiple signaling pathways, has been demonstrated to play a crucial role in various types of cancers. However, little is known about its function in non-small cell lung cancer (NSCLC). OBJECTIVE: Our objective is to explore the function of PMEPA1 and its potential mechanisms in NSCLC progression. METHODS: PMEPA1 expression and prognostic significance in adenocarcinoma of lung cancer (LUAD) and squamous cell carcinoma of lung cancer (LUSC) were determined using Gene Expression Profiling Interactive Analysis (GEPIA). Next, a series of cell assays were performed to examine whether overexpression or depletion of PMEPA1 affected the malignant behaviors of NSCLC H1299 cells, such as proliferation and migration. Luciferase reporter gene assays and SP600125 (a JNK inhibitor) were employed to ascertain the regulatory relationship between PMEPA1 and JNK. RESULTS: PMEPA1 is overexpressed in LUAD and LUSC tissues and portends a worse prognosis for cancer patients. Gain and loss of function experiments demonstrated that PMEPA1 executes oncogenetic function in H1299 cells. Mechanism studies elucidated that PMEPA1 stimulated the transcriptional activity of the JNK pathway. CONCLUSION: PMEPA1 increased the H1299 cell viability, proliferation, and migration which works, at least partially, by triggering the JNK activity. Hence, our findings support that the PMEPA1/JNK axis might be a promising therapeutic target for this challenging disease.

Hypoxia-induced SPOP attenuates the mobility of trophoblast cells through inhibition of the PI3K/AKT/GSK3ß pathway.

Placental hypoxia has been implicated in pregnancy pathologies such as pre-eclampsia and intrauterine growth restriction. However, the underlying mechanism by which the trophoblasts respond to hypoxia remains unclear. Speckle-type POZ protein (SPOP), an E3 ubiquitin ligase adapter, was previously reported to play important roles in various physiological and pathological processes. This study aims to investigate the expression and biological functions of SPOP after exposure to cobalt chloride (CoCl2 )-mimicked hypoxia conditions using human trophoblast-derived choriocarcinoma cell lines and extravillous cytotrophoblast. These data showed that SPOP protein was directly induced by CoCl2 -mimicked hypoxia and regulated by HIF-1α at the posttranscription level. CoCl2 treatment could dramatically influence the localization of SPOP in trophoblasts, especially the accumulation of SPOP into the nucleus. In addition, both CoCl2 -mimicked hypoxia and induction of endogenous SPOP expression by lentivirus transfection attenuated the migration and invasion abilities of trophoblasts. Furthermore, we demonstrated that SPOP was involved in CoCl2 -induced the inhibition of the PI3K/AKT/GSK3ß pathway in placental trophoblasts. Taken together, these data indicate that accumulation of HIF-1α augments the expression of SPOP in trophoblasts, which impairs trophoblastic mobility by targeting the PI3K/AKT/GSK3ß pathway. This potentially leads to insufficient uterine spiral artery remodeling and suboptimal placental perfusion, and thus the development of pregnancy-related complication.

Nrf2/ARE pathway activation is involved in negatively regulating heat-induced apoptosis in non-small cell lung cancer cells.

Hyperthermia, particularly in combination with chemoradiotherapy, is widely used to treat various cancers. However, hyperthermia treatment is often insufficient due to thermo-tolerance. To date, the detailed mechanism underlying thermo-tolerance has not been clarified. The nuclear factor erythroid 2-related factor 2 (Nrf2)/ antioxidant response element (ARE) pathway is an important cellular cytoprotective defense system that is activated by various stresses. In this study, using immunocytochemistry and western blot analysis, we demonstrated that heat stress induced Nrf2/ARE activation through the nuclear translocation of Nrf2 in non-small cell lung cancer cells. Luciferase activity was also increased. Additionally, antioxidant enzymes were increased through Nrf2 activation after heat stress. Transfection of lung cancer cells with siRNA directed against Nrf2 increased heat cytotoxicity and cell apoptosis. Heat stress could induce reactive oxygen species (ROS) accumulation, while the antioxidant NAC obviously reduced cell apoptosis ratio, indicating that heat stress induced cell apoptosis in a ROS-dependent manner. Knockdown of Nrf2 led to an abnormal elevation of ROS, and the antioxidant NAC could increase Nrf2 activation, indicating that ROS and Nrf2 act within a negative feedback loop. Taken together, these results demonstrated that Nrf2 pathway is important for maintaining resistance to heat stress, and we postulated that Nrf2 may represent a potential therapeutic target for hyperthermia in lung cancer.

Genomic Profiling Reveals Synchronous Bilateral Lung Adenocarcinomas With Distinct Driver Alterations of EML4-ALK or TPM3-ROS1 Fusion: A Case Report.

Background: ALK and ROS1 rearrangement accounts for 3-6% and 1-3% of non-small cell lung cancers, respectively, while coexistence of them in the same patient is extremely rare. Only three cases have ever been reported with concurrent ALK/ROS1 fusions in the same tumor indicating tumor heterogeneity. Therefore, comprehensive genetic profiling via next-generation sequencing (NGS) is needed to provide fully molecular diagnosis. Case Presentation: A 50-year old Chinese female with resectable stage IB bilateral lung adenocarcinomas (ADCs) harbored EML4 exon 6-ALK exon 19 and TPM3 exon 8-ROS1 exon 35 fusions in the right lower and the left upper tumors, respectively, identified by clinical NGS test targeting 425 cancer-relevant genes. The results were further confirmed at RNA level using RNA-seq. Genomic evolution analysis reveals that these bilateral tumors are synchronous multiple primary lung cancers with no shared somatic alterations for both genes and arm-level copy number variations (CNVs). No recurrence was observed during 12 months of post-surgery follow-up. Conclusions: Our case is the first report of concurrent ALK/ROS1 fusions as distinct driver events of synchronous multiple primary lung cancers, and highlights the importance of individual genetic testing for each of the multiple primary tumors for fully molecular diagnosis and precise treatment decision-making.

Role of postoperative adjuvant radiotherapy for locally advanced laryngeal cancer: a meta-analysis.

BACKGROUND: Studies have shown mixed results on the role of postoperative adjuvant radiotherapy (PORT) in surgically managed locally advanced laryngeal cancer. OBJECTIVES: The aim of this study is to review and investigate the role of PORT in patients with locally advanced laryngeal cancer using meta-analysis. MATERIALS AND METHODS: Relevant studies were searched using PubMed and eligible information has been extracted. Then, meta-analysis of hazard ratio (HR) was performed to evaluate the role of PORT in locally advanced laryngeal cancer. RESULTS: This meta-analysis included 7 published studies containing 2007 patients. For overall survival (OS), patients of locally advanced laryngeal cancer who were treated with PORT have a combined hazard ratio (HR) of 0.67 with 95%CI (0.56, 0.79), compared to those who were not treated with PORT, which was significantly associated with better survival. PORT was also associated with a better disease-free survival (DFS) and local control rate (LCR) in patients with locally advanced laryngeal cancer. The pooled HR and 95%CI for DFS and LCR were 0.72 (0.53, 0.99) and 0.29 (0.09, 0.99), respectively. CONCLUSIONS AND SIGNIFICANCE: This study suggested that PORT could improve the survival of patients with surgically managed locally advanced laryngeal cancer.

Meta-Analysis of Circulating Endothelial Cells and Circulating Endothelial Progenitor Cells as Prognostic Factors in Lung Cancer.

BACKGROUND: The aim of this study was to analyze the prognostic implications of pretreatment circulating endothelial cells (CECs) and circulating endothelial progenitor cells (CEPCs) for the survival of patients with lung cancer. MATERIALS AND METHODS: Relevant literature was identified using Medline and EMBASE. Patient clinical characteristics, overall survival (OS) and progression-free survival (PFS) together with CEC and CEPC positive rates before treatment were extracted. STATA 12.0 was used for our analysis and assessment of publication bias. RESULTS: A total of 13 articles (8 for CEC and 5 for CEPC, n=595 and n=244) were pooled for the global meta-analysis. The odds ratio (OR) for OS predicted by pretreatment CECs was 1.641 [0.967, 2.786], while the OR for PFS was 1.168 [0.649, 2.100]. The OR for OS predicted by pretreatment CEPCs was 12.673 [5.274, 30.450], while the OR for PFS was 4.930 [0.931, 26.096]. Subgroup analyses were conducted according to clinical staging. Odds ratio (OR) showed the high level of pretreatment CECs only correlated with the OS of patients with advanced lung cancer (stage III-IV). CONCLUSIONS: High counts of CECs seem to be associated only with worse 1-year OS in patients with lung cancer, while high level of pretreatment CEPCs correlate with both worse PFS and OS.

The upregulation of dihydropyrimidine dehydrogenase in liver is involved in acquired resistance to 5-fluorouracil.

BACKGROUND: Acquired resistance to 5-fluorouracil (5-FU) is one of the important reasons for failure in 5-FU-based chemotherapy. The upregulation of dihydropyrimidine dehydrogenase (DPD) in tumours was reported as an important factor for acquired 5-FU resistance. The aim of this study is to examine whether intra-hepatic DPD was involved in acquired 5-FU resistance. METHODS: HT-29 human colorectal xenograft tumours were established in nude mice. After long-term exposure to 5-FU, some of the tumour became "resistant" and the others remained "sensitive" to 5-FU. DPD expression levels in the livers and tumours of "resistant", "sensitive" or untreated mice were examined, and pharmacokinetics of 5-FU in rats' plasma were investigated. Gimeracil, a DPD inhibitor, was checked whether it could reverse the reduced bioavailability of 5-FU. RESULTS: DPD expression was upregulated obviously in tumours of "resistant" mice as reported previously. Importantly, DPD expression was also upregulated significantly in livers of "resistant" mice, compared with those of "sensitive" or untreated mice. Furthermore, the upregulation of DPD expression in livers led to accelerated metabolism of 5-FU. Gimeracil was found to reverse the reduced serum 5-FU concentration. The cultured tumour cells from 5-FU treated mice showed relative sensitivity to higher concentration of 5-FU, even the "resistant" tumour cells. CONCLUSION: Our study suggested that the upregulation of DPD in liver may be involved in acquired resistance to 5-FU, and DPD inhibitors or increasing 5-FU dosage may have potential application in overcoming 5-FU acquired resistance.

Different combination schedules of gemcitabine with endostar affect antitumor efficacy.

PURPOSE: Antiangiogenic drugs inhibit tumor growth by decreasing blood supply and causing transient "normalization" of the tumor vasculature, thereby improving the delivery of systemic chemotherapy. A higher dose of antiangiogenic drugs may lead to a more marked decrease in intratumoral blood flow but may concomitantly cause a decrease in delivery of chemotherapeutic agents. The purpose of this study was to define an optimal schedule for the combination of gemcitabine with a recombinant endostatin, endostar. METHODS: We evaluated the antitumor effects with different schedules of gemcitabine combined with or without endostar. The changes of vascular endothelial growth factor (VEGF) levels in tumor extracts and sera after gemcitabine treatment were examined. Endostar was also assessed for its abilities to inhibit the increase in VEGF levels. Apoptotic cells and microvessel density within tumor tissue were also examined. RESULTS: Endostar administered simultaneously with or following gemcitabine improved the inhibition of tumor growth, compared with gemcitabine alone. VEGF levels decreased immediately after gemcitabine treatment, but increased in the following several days. Endostar administered simultaneously with or following gemcitabine could inhibit the increase in VEGF levels, thereby cause a decreased vessel density and an increased apoptosis in tumor tissue. CONCLUSIONS: Our finding suggested that endostar given simultaneously with or following gemcitabine might be optimal to enhance the antitumor effect.

Comparative proteomic analysis of irinotecan-sensitive colorectal carcinoma cell line and its chemoresistant counterpart.

In this study, we used two-dimensional gel electrophoresis and MALDI-Q-TOF-MS/MS analysis to examine the global protein expression of a pair of colorectal carcinoma cell lines, SW620 and irinotecan-resistant SW620. Of the 30 spots identified as differentially expressed proteins (±over twofold, P<0.05) between the two cell lines, 26 spots (corresponding to 26 unique proteins) were positively identified by MALDI-Q-TOF-MS/MS analysis. These proteins could be grouped into main classes including metabolism (15.38%), cell SSproliferation/differentiation (11.53%), molecular chaperone (11.53%), mRNA splicing (11.53%), and so on. The proteins, which might be involved in the development of tumor drug resistance, such as α-enolase, cofilin, and thioredoxin-dependent peroxide 1, have been validated by western blot analysis and have been discussed. The proteins identified in this study may be useful in showing the mechanisms underlying irinotecan resistance.

Prognostic influence of metformin as first-line chemotherapy for advanced nonsmall cell lung cancer in patients with type 2 diabetes.

BACKGROUND: It has been reported that antidiabetic drugs affect the risk of cancer and the prognosis of patients with diabetes, but few studies have demonstrated the influence of different antidiabetic agents on outcomes after anticancer therapy among patients with cancer. The objective of this study was to evaluate the influence of the antidiabetic drugs metformin and insulin on the prognosis of patients with advanced nonsmall cell lung cancer (NSCLC) plus type 2 diabetes who received first-line chemotherapy. METHODS: Data on patients with NSCLC who had diabetes from 5 hospitals in China during January 2004 to March 2009 were reviewed retrospectively. Ninety-nine patients were included in the final analysis. The influence of metformin and insulin on chemotherapy response rates and survival in these patients was evaluated. RESULTS: Chemotherapy with metformin (Group A) produced superior results compared with insulin (Group B) and compared with drugs other than metformin and insulin (Group C) in terms of both progression-free survival (PFS) (8.4 months vs 4.7 months vs 6.4 months, respectively; P = .002) and overall survival (OS) (20.0 months vs 13.1 months vs 13.0 months, respectively; P = .007). Although no significant differences in the response rate (RR) were observed between these 3 groups, when groups B and C (ie, the nonmetformin group) were combined, there was a tendency for better disease control in Group A than that in nonmetformin group. No significant difference in survival was observed between chemotherapy with insulin (Group B) versus other drugs (Group C). CONCLUSIONS: The current data suggested that metformin may improve chemotherapy outcomes and survival for patients who have NSCLC with diabetes.

Interleukin-15 enhances T-cell responses by stimulation with dendritic cells.

INTRODUCTION: Cytokines play important roles in regulating immune responses. Interleukin-2 (IL-2) has usually been used as an adjuvant to enhance antitumour immune responses. However, its crucial role in activation-induced cell death, inhibition of homeostatic proliferation of CD8+ memory T cells and its notable biological side effects impair its prospect of application. IL-15 has several similar functions to IL-2 and shows potential advantages over IL-2, and is being investigated to enhance antitumour dendritic cell (DC) vaccine strategies in our ongoing studies. OBJECTIVE: In this preliminary study, we evaluated the ability of IL-15, compared with IL-2, to act as an adjuvant to enhance T-cell responses activated by DCs in vitro. MATERIALS AND METHODS: Bone marrow-derived DCs (BMDCs) were pulsed with tumour antigens and used to stimulate lymphocyte responses in the presence of IL-15 or IL-2. The activated T lymphocytes were examined by flow cytometric analysis, and interferon-γ (IFN-γ) enzyme-linked immunospot and cytotoxicity assays. RESULTS: IL-15 was observed to activate lymphocytes with comparable phenotype characteristics of activated/memory CD8+ lymphocytes, compared with IL-2. Both in primary and secondary stimulation with DCs, when using IL-15 as an adjuvant, activated lymphocytes showed higher proportions of IFN-γ-secreting subsets. In secondary stimulation with BMDCs in the presence of IL-15, the activated lymphocytes showed a stronger cytotoxicity to antigen-specific tumour target cells. CONCLUSIONS: Our study suggested that IL-15 might be a prospective adjuvant for a DC vaccine strategy against cancers. The further observation that IL-15 acts as an adjuvant for an antitumour DC vaccine strategy is worth investigating.

Interaction of green tea polyphenol epigallocatechin-3-gallate with sunitinib: potential risk of diminished sunitinib bioavailability.

Sunitinib, a novel oral multi-targeted tyrosine kinase inhibitor for patients with metastatic renal cell carcinoma (mRCC) and advanced gastrointestinal stromal tumor, has a good prospect for clinical application and is being investigated for the potential therapy of other tumors. We observed the phenomenon that drinking tea interfered with symptom control in an mRCC patient treated with sunitinib and speculated that green tea or its components might interact with sunitinib. This study was performed to investigate whether epigallocatechin-3-gallate (EGCG), the major constituent of green tea, interacted with sunitinib. The interaction between EGCG and sunitinib was examined in vitro and in vivo. (1)H nuclear magnetic resonance ((1)H-NMR) spectroscopy and mass spectrometry (MS) were used to analyze the interaction between these two molecules and whether a new compound was formed. Solutions of sunitinib and EGCG were intragastrically administered to rats to investigate whether the plasma concentrations of sunitinib were affected by EGCG. In this study, we noticed that a precipitate was formed when the solutions of sunitinib and EGCG were mixed under both neutral and acidic conditions. (1)H-NMR spectra indicated an interaction between EGCG and sunitinib, but no new compound was observed by MS. Sticky semisolid contents were found in the stomachs of sunitinib and EGCG co-administrated mice. The AUC(0-∞) and C (max) of plasma sunitinib were markedly reduced by co-administration of EGCG to rats. Our study firstly showed that EGCG interacted with sunitinib and reduced the bioavailability of sunitinib. This finding has significant practical implications for tea-drinking habit during sunitinib administration.