Clinical significance of low expression of CADM3 in breast cancer and preliminary exploration of related mechanisms.

BACKGROUND: Cell adhesion molecule 3 (CADM3), a transmembrane glycoprotein on cell membranes, plays a role in the way of ligand and receptor interaction. However, there are few studies on CADM3 in tumors, and how it works in breast cancer (BC) remains unclear. METHODS: The Cancer Genome Atlas (TCGA) database and clinical samples were used to analyze CADM3 expression and its correlation with clinicopathological factors and prognosis. Its correlation with immune infiltration was analyzed by TCGA. The effects of CADM3 on proliferation and migration were investigated by cell clonal formation, CCK-8, cell scratch and transwell assay. Protein interaction network was prepared and the function prediction of related genes was conducted. The correlation between CADM3 and MAPK pathway was further explored by western blot experiment. RESULTS: The expression of CADM3 in BC tissues were significantly lower than that in adjacent normal tissues. High level of CADM3 was related to better prognosis of BC patients. CADM3 was an independent prognostic factor for BC. Expression of CADM3 was significantly associated with the status of ER and PR, age and PAM50 subtypes. CADM3 positively related to many immune infiltrating cells. Overexpression of CADM3 can notably reduce cell proliferation and migration. CADM3 was related to MAPK pathway and the phosphorylation of ERK1/2 and JNK1 was inhibited in BC cells with high CADM3. CONCLUSIONS: Our research reveals the clinical significance of CADM3 in BC and indicates the critical roles of CADM3 in immune infiltration and MAPK pathway.

High expression of CCDC69 is correlated with immunotherapy response and protective effects on breast cancer.

BACKGROUND: As a molecule controlling the assembly of central spindles and recruitment of midzone component, coiled-coil domain-containing protein 69 (CCDC69) plays an important role in multiple cancers. Currently, the relationships between CCDC69 and immune infiltration or immunotherapy in breast cancer remain unclear. METHODS: The expression and prognostic significance of CCDC69 in breast cancer were comprehensively analyzed by quantitative real-time PCR, immunohistochemical staining and various databases. The data source of differentially expressed genes, gene set enrichment analysis, and immune cell infiltration analysis came from The Cancer Genome Atlas (TCGA) database. Single-cell analysis based on IMMUcan database was used. The protein-protein interaction network was developed applying STRING, Cytoscape, CytoHubba, and GeneMANIA. TISIDB was employed in analyzing the CCDC69 co-expressed immune related genes. The correlations between CCDC69 and immunotherapy or immune-related scores were analyzed by CAMOIP and TISMO. Ctr-db was also used to conduct drug sensitivity analysis. RESULTS: The mRNA of CCDC69 was downregulated in breast cancer tissues compared with normal tissues. Higher CCDC69 expression was associated with a better breast cancer prognosis. Enrichment analysis showed that the co-expression genes of CCDC69 were mainly related to immune-related pathways. The expression of CCDC69 was found to be positively correlated with multiple tumor-suppression immune infiltration cells, especially T cells and dendritic cells. Meanwhile, high CCDC69 expression can predict better immunotherapy responses when compared with low CCDC69 expression. After the interferon-gamma treatment, the CCDC69 expression was elevated in vitro. CCDC69 expression was a reliable predictor for the response status of two therapeutic strategies in breast cancer. CONCLUSIONS: Our research revealed the clinical significance of CCDC69 in breast cancer and validated the critical roles of CCDC69 in the tumor immune infiltration and immunotherapy responses.

Efficacy and safety of anti-PD-1/PD-L1 therapy in the treatment of advanced colorectal cancer: a meta-analysis.

BACKGROUND: Immune checkpoint inhibitors have shown promise in microsatellite instability-high/mismatch repair deficient (MSI-H/dMMR) advanced colorectal cancer (CRC) immunotherapy, and many clinical trials have been conducted. OBJECTIVE: To evaluate the efficacy and safety of PD-1/PD-L1 inhibitors in advanced CRC. METHOD: PubMed, Web of Science, Embase, and The Cochrane Library were searched for relevant studies up to September 2021. A retrospective cross-sectional data analysis was performed and Stata 16 software was used for analyses. RESULTS: Sixteen studies including 1503 patients were analyzed. The objective response rate (ORR) of anti-PD-1/PD-L1 was 23% (95% CI 0.14, 0.31); the overall 1-year survival rate (OSR) was 57% (95% CI 0.42, 0.73). The ORR of MSI-H/dMMR advanced CRC was 37% (95% CI 0.25, 0.48) and that of microsatellite stable/mismatch repair proficient (MSS/pMMR) disease was 11% (95% CI 0.06, 0.16). The ORR was 42% in the BRAF mutant subgroup and 19% in the RAS mutant group. The ORR was 14% in the PD-L1 ( +) subgroup and 32% in the PD-L1(-) subgroup. The rate of adverse effects was 85% (95% CI 0.80, 0.91). CONCLUSION: Anti-PD-1/PD-L1 therapy in MSI-H/dMMR advanced CRC was associated with improved survival. Anti PD-1/PD-L1 combined with antiangiogenic drugs, targeted agents, or chemotherapy might be effective in MSS mCRC. Immunotherapy was effective for the BRAF mutant and KRAS/NRAS(RAS) mutant CRC. Low expression of PD-L1 was a potential predictive marker for positive response and outcome. The high incidence of adverse events at 85% was worthy of further investigation. Further analysis with a higher number of high-quality studies is needed to verify the conclusions.

Corn embryo ameliorates cognitive dysfunction and anxiety-like behaviors in D-galactose-induced aging rats via attenuating oxidative stress, apoptosis and up-regulating neurotrophic factors.

Aging is the primary cause of neurodegenerative diseases, which are mainly characterized by cognitive decline and neuropsychiatric symptoms. Corn embryo, an important component of corn kernels, contains plenty of essential nutrients and bioactive compounds. However, corn embryo is often removed in the process of refining corn. To reveal potential biological benefits of corn embryo, the present study investigated the intervention effects of corn embryo on age-related cognitive decline and neuropsychiatric symptoms. Ninety male Wistar rats were randomly divided into six groups: Control, Corn embryo, Aging model, Low-, Medium- and High-dose intervention group. Aging models induced by an intraperitoneal injection of 60 mg/kg D-galactose plus a gavage of 200 mg/kg aluminum chloride were intervened with a gavage of 0.3, 0.6 or 1 g/kg corn embryo while the Control and Corn embryo groups received saline and 0.6 g/kg corn embryo respectively. Morris water maze and open field test were performed to assess cognitive abilities and anxiety-like behaviors. Brain biochemical parameters including the malondialdehyde, glutathione, glutathione sulfhydryl transferase and γ-glutamylcysteine synthetase were detected to evaluate oxidative stress levels. The mRNA expression of brain-derived neurotrophic factor was determined to estimate neurotrophic factor levels. Besides, histopathological alterations were visualized by hematoxylin-eosin staining and neuronal apoptosis levels were measured by the immunohistochemical staining of Bax and Bcl-2. Ultimately, the mimetic aging rats showed significant cognitive impairment (n = 15, P < 0.01) and anxiety-like behaviors (n = 15, P < 0.01), increased oxidative stress (n = 5, P < 0.001), neurodegeneration (n = 5, P < 0.001) and apoptosis (n = 5, P < 0.01) and reduced neurotrophic factors (n = 5, P = 0.074) in the brain. However, corn embryo effectively prevented the above undesirable neurobehavioral alterations via attenuating oxidative stress (n = 5, P < 0.01), neurodegeneration (n = 5, P < 0.001) and apoptosis (n = 5, P < 0.01) and increasing the levels of neurotrophic factors (n = 5, P < 0.001), suggesting its strong neuroprotective effects.

The m6A methyltransferase METTL14 inhibits the proliferation, migration, and invasion of gastric cancer by regulating the PI3K/AKT/mTOR signaling pathway.

BACKGROUND: N6-methyladenosine (m6A) modification may participate in the regulation of occurrence and development of tumors. However, the m6A level and the potential regulatory mechanism of m6A in gastric cancer (GC) remain uncertain. METHODS: RNA m6A quantification assay was conducted to detect the m6A level in GC tissues and cell lines. Methyltransferase-like 14 (METTL14) expression in GC tissues was explored by bioinformatics and immunohistochemistry. Then, the function of METTL14 in GC cells was examined by CCK-8, colony formation assay, wound healing assay, and Transwell assay. Besides, Western blotting was conducted to probe the PI3K/AKT/mTOR pathway and the epithelial-mesenchymal transformation (EMT) pathway-related gene expression. RESULTS: The m6A modification level was decreased in GC and METTL14 was a key regulator resulting in m6A disorder in GC. METTL14 was downregulated in GC by analyzing both clinical samples and bioinformatics. METTL14 overexpression suppressed GC cell proliferation and aggression by deactivating the PI3K/AKT/mTOR pathway and the EMT pathway, respectively. CONCLUSIONS: Our findings indicate that METTL14 partakes in the biological process of GC as a tumor suppressor and may be an emerging biomarker in GC.

MiR-25-3p targets PTEN to regulate the migration, invasion, and apoptosis of esophageal cancer cells via the PI3K/AKT pathway.

BACKGROUND: Esophageal cancer (EC) is one of the most common malignant tumors of the digestive system. MiR-25-3p was proved to be a biomarker for the diagnosis and treatment of many cancers. MiR-25-3p was found to be high expressed in the blood of EC patients. The aim of the present study was to explore the effect of miR-25-3p and its target gene on EC. METHODS: miR-25-3p expression in the blood of EC patients and EC cells was detected by RT-qPCR. The target of miR-25-3p was identified by bioinformatics and luciferase reporter assay. After transfection, cell viability, apoptosis, migration, and invasion were detected by MTT, flow cytometry, wound healing, and transwell assays, respectively. The expressions of PTEN, Bax, Bcl-2, cleaved Caspase-3, p-PI3K, PI3K, p-AKT, and AKT were detected by Western blot. RESULTS: MiR-25-3p was high expressed in the blood of EC patients and EC cells. MiR-25-3p targeted PTEN and inhibited the expression of PTEN. MiR-25-3p mimic increased the viability, migration, invasion and the expressions of Bcl-2, and inhibited the apoptosis and the expression of Bax and cleaved caspase-3 in EC cells. MiR-25-3p mimic also enhanced the expressions of p-PI3K and p-AKT and the ratios of p-PI3K/PI3K and p-AKT/AKT in EC cells. PTEN overexpression not only had an opposite effect of miR-25-3p mimic, but also reversed the effect of miR-25-3p mimic on EC cells. CONCLUSION: MiR-25-3p targeted PTEN to promote the migration and invasion, and inhibit apoptosis of EC cells via the PI3K/AKT pathway, which might provide a new therapeutic target for EC treatment.

miR-28-5p targets MTSS1 to regulate cell proliferation and apoptosis in esophageal cancer.

Esophageal cancer (EC) is one of the most common aggressive malignant diseases worldwide. miR-28-5p plays important regulatory roles in many cancers including human EC. However, the molecular mechanism and potential role of miR-28-5p in EC remain uncertain. In this study, qRT-PCR and western blot analysis revealed that miR-28-5p expression was up-regulated and metastasis suppressor-1 (MTSS1) was down-regulated in EC tissues relative to matched para-cancer tissues. Cell counting kit-8 (CCK-8) assay demonstrated that miR-28-5p mimics increased cell viability, and miR-28-5p inhibitor decreased it. Flow cytometry (FCM) assay indicated that miR-28-5p mimics promoted cell cycle entry, while miR-28-5p inhibitor reduced it and induced cell apoptosis. Moreover, miR-28-5p mimics up-regulated the expressions of cyclin A, cyclin dependent kinase 2 (CDK2), cyclin D1, and cyclin E but down-regulated the expressions of cleaved caspase-3 and cleaved caspase-9, which was abolished by miR-28-5p inhibitor. Furthermore, luciferase reporter assay verified that miR-28-5p directly targeted MTSS1 3'UTR and down-regulated its expression. MTSS1 overexpression in TE-1 cells inhibited cell proliferation and promoted apoptosis induced by miR-28-5p mimics, whereas silencing of MTSS1 reversed cell progression induced by miR-28-5p inhibitor. We also demonstrated that miR-28-5p could promote esophageal tumor formation in vivo. Hematoxylin-eosin staining, immunohistochemistry, and TUNEL assays confirmed that miR-28-5p antagomir inhibited cell growth and accelerated apoptosis. Our results suggest that miR-28-5p may induce cell proliferation and suppress apoptosis to promote EC tumor formation via decreasing MTSS1 expression. Thus, miR-28-5p may be a potential target for human EC therapy.

A novel lymph node staging system for gastric cancer including modified Union for cancer Control/American Joint Committee on cancer and Japanese Gastric Cancer Association criteria.

BACKGROUND: The TNM system of the International Union for Cancer Control/American Joint Committee on Cancer (UICC/AJCC) and the Japanese Gastric Cancer Association (JGCA) systems are the most used lymph node (LN) staging systems in gastric cancer. This study estimated the influence of anatomic location-based node stations on survival and proposed a new staging method based on both the number and anatomical distribution of metastatic LNs (mLNs). METHODS: Stage I-III gastric cancer patients with radical gastrectomy were retrospectively evaluated. Overall survival (OS) was estimated in 1786 patients with UICC/AJCC stage N1-N3b disease and compared with estimates obtained using JGCA group 1-3 mLN staging. RESULTS: The OS of UICC/AJCC stage N1-N3b patients with group 2 JGCA mLNs was significantly worse than that of patients with only group 1 mLNs. The OS of the patients with group 2 mLNs was similar to that of patients with group 1 mLNs but in the next more advanced UICC/AJCC-N stage. The OS of patients with group 3 mLNs was worse than that of patients with any UICC/AJCC-N stage and was similar to that of N3b patients with group 2 mLNs. A new pathological node (pN) staging classification was developed that advanced the N-staging of patients with group 2 mLNs. It was a better indicator of prognosis than the eighth UICC/AJCC-N and the thirteenth JGCA group staging systems. CONCLUSIONS: A simple, accurate pN staging system including both the number and location of mLNs had improved homogeneity, discriminatory ability, and gradient monotonicity.

Microwave ablation versus sorafenib for intermediate-Stage Hepatocellular carcinoma with transcatheter arterial chemoembolization refractoriness: a propensity score matching analysis.

Purpose: To compared the benefits of sorafenib with microwave ablation (MWA) in intermediate-stage hepatocellular carcinoma (HCC) patients with tumor size ≤7 cm and tumor number ≤5 after Transcatheter Arterial Chemoembolization (TACE) failure.Methods: A retrospective, single-center study was conducted using a one-to-one propensity score matching (PSM) analysis and involved 52 intermediate-stage HCC patients with absence of evidence of intrahepatic vascular invasion and extrahepatic metastasis after TACE failure and underwent treatment with MWA or sorafenib between 2007 and 2019. The overall survival (OS) and progression-free survival (PFS) were evaluated by the Kaplan-Meier method. The factors with OS and PFS were determined by Cox regression.Results: Of the 52 patients included in our study, 30 (57.7%) underwent MWA and 22 (42.3%) received sorafenib. After PSM, 22 pairs were enrolled into different groups for further analysis. Patients in the MWA-group had a significantly longer median PFS than patients in the sorafenib-group on both before (median, 9.3 vs. 2.8 months, p = .001) and after PSM (median, 9.0 vs. 2.8 months, p = .006). They also had a significantly longer median OS than patients in the sorafenib-group on before (median, 48.8 vs. 16.6 months, p = .001) and after PSM (median, Not reached vs. 16.6 months, p = .001). Besides, Cox regression analysis showed that the treatment and age were the independent prognostic factors of OS and PFS (p＜0.05).Conclusions: MWA was superior to sorafenib in improving survival for intermediate-stage hepatocellular carcinoma (HCC) patients with tumor size ≤7 cm and tumor number ≤5 after TACE failure.Key PointsCompared with sorafenib, microwave ablation may be a more reasonable alternative treatment for intermediate-stage hepatocellular carcinoma (HCC) patients with tumor size ≤7 cm and tumor number ≤5 after TACE refractoriness.The treatment (MWA vs sorafenib) and the age of patients were the independent prognostic factors of OS and PFS.

MicroRNA-93-5p promotes epithelial-mesenchymal transition in gastric cancer by repressing tumor suppressor AHNAK expression.

BACKGROUND: Gastric cancer (GC) is a common cause of cancer-related mortality worldwide, and microRNAs (miRNAs) have been shown to play an important role in GC development. This study aims to explore the effect of microRNA-93-5p (miR-93-5p) on the epithelial-mesenchymal transition (EMT) in GC, via AHNAK and the Wnt signaling pathway. METHODS: Microarray-based gene expression analysis was performed to identify GC-related differentially expressed miRNAs and genes. Then the expression of the miR-93-5p was examined in GC tissues and GC cell lines. The targeting relationship between miR-93-5p and AHNAK was verified by a dual luciferase reporter gene assay. In an attempt to ascertain the contributory role of miR-93-5p in GC, miR-93-5p mimic or inhibitor, as well as an AHNAK overexpression vector, were introduced to HGC-27 cells. HGC-27 cell migration and invasive ability, and EMT were assayed using Transwell assay and western blot analysis. Regulation of the Wnt signaling pathway was also assessed using TOP/FOP flash luciferase assay. RESULTS: miR-93-5p was highly expressed in GC tissue samples and cells. Notably, miR-93-5p could target and negatively regulate AHNAK. Down-regulation of miR-93-5p or overexpression of AHNAK could suppress the migration and invasion abilities, in addition to EMT in GC cells via inactivation of the Wnt signaling pathway. CONCLUSION: Taken together, downregulation of miR-93-5p attenuated GC development via the Wnt signaling pathway by targeting AHNAK. These findings provide an enhanced understanding of miR-93-5p as a therapeutic target for GC treatment.

Dietary isoflavones or isoflavone-rich food intake and breast cancer risk: A meta-analysis of prospective cohort studies.

BACKGROUND & AIMS: Previous studies implied that dietary isoflavone intake may reduce the risk of developing breast cancer, but some have shown ambiguous results. This study aimed to systematically evaluate and summarize available evidence on the effect dietary isoflavone intake has on the risk of developing breast cancer. METHODS: PubMed, Embase, and the Cochrane Library were searched for prospective cohort studies published through April 2017 that evaluated the effect of dietary isoflavone intake on the development of breast cancer. RESULTS: Sixteen prospective cohort studies, involving 11,169 breast cancer cases and 648,913 participants, were identified and included in our data analysis. The pooled relative risk (RR) of breast cancer was 0.99 for high versus low intake of isoflavones (95% confidence interval [CI], 0.91-1.09; P = 0.876) and 0.99 for moderate versus low intake of isoflavones (95%CI, 0.92-1.05; P = 0.653), with insignificant heterogeneity (P = 0.187 for high versus low, and P = 0.192 for moderate versus low). While a moderate consumption of soy-based foods did not significantly affect breast cancer risk, a high intake of soy-based foods associated with a lower risk of developing breast cancer. Considering specific foods, an increased the risk of developing breast cancer was seen with a moderate intake of formononetin, but no significant associations were found between breast cancer risk and other isoflavone-rich diets. CONCLUSIONS: The present meta-analysis indicates that women with a high dietary intake of soy foods may experience a statistically significant reduction in breast cancer risk. However, moderate formononetin consumption may increase the risk of developing breast cancer.

Downregulation of RASSF6 promotes breast cancer growth and chemoresistance through regulation of Hippo signaling.

This study aims to investigate the clinical significance and biological function of RASSF6 in human breast cancers. RASSF6 protein was found to be downregulated in 42 of 95 human breast cancer tissues by immunohistochemistry, which was associated with advanced TNM stage and nodal metastasis. The rate of RASSF6 downregulation was higher in Triple-negative breast cancer (TNBC). Downregulation of RASSF6 protein was also found in breast cancer cell lines, especially in TNBC cell lines. Overexpression RASSF6 inhibited cell growth rate and colony formation ability in MDA-MB-231 cell line. Depletion of RASSF6 promoted proliferation rate and colony formation ability in T47D cell line. Flow cytometry/PI staining demonstrated that RASSF6 inhibited cell cycle transition. AnnxinV/PI analysis showed that RASSF6 overexpression upregulated apoptosis induced by cisplatin (CDDP) while RASSF6 depletion inhibited apoptosis. JC-1 staining showed that RASSF6 overexpression inhibited mitochondrial membrane potential. Western blot analysis demonstrated that RASSF6 repressed cyclin D1, YAP while upregulated p21, cleaved caspase 3 and cytochrome c expression. In addition, RASSF6 activated Hippo signaling pathway by upregulating MST1/2 and LATS1 phosphorylation. Restoration of YAP inhibited cleaved caspase 3 and cytochrome c which were induced by RASSF6. Restoration of YAP also reduced the rate of CDDP induced apoptosis. In conclusion, this study provided evidence that RASSF6 functions as a potential tumor suppressor in human breast cancer through activation of Hippo pathway.

TRIM32 promotes proliferation and confers chemoresistance to breast cancer cells through activation of the NF-κB pathway.

Dysregulation of TRIM32 has been implicated in several human cancers, however, its clinical significance and biological function in breast cancer have not been investigated. Using immunohistochemistry, we found that TRIM32 expression is upregulated in breast cancer tissues and that it correlates with advanced stage and poor prognosis. TRIM32 is also overexpressed in 4/7 breast cancer cell lines. CCK8 and colony formation assays showed that TRIM32 depletion inhibited proliferation and colony formation in the T47D cell line, while TRIM32 overexpression promoted MCF-7 cell growth and colony formation. Cell viability and Annexin V/PI staining demonstrated that TRIM32 maintained breast cancer cell survival and reduced apoptosis rate when cells were treated with cisplatin. Western blot analysis demonstrated that TRIM32 overexpression resulted in an upregulation of p-IκB, p-p65, cIAP1, and cIAP2 and a downregulation of p21 and p27 in MCF-7 cells. TRIM32 depletion in T47D cells demonstrated the opposite results, suggesting that TRIM32 may activate the NF-κB pathway. The NF-κB inhibitor BAY 11-7082 blocked the effects of TRIM32 on cisplatin resistance and cIAP1/2 protein regulation. Taken together, the present study demonstrates that TRIM32 downregulates p21/p27 and upregulates IAP family proteins to facilitate breast cancer cell growth and inhibit drug-induced apoptosis, possibly through the NF-κB signaling pathway.

ERCC2/XPD Lys751Gln alter DNA repair efficiency of platinum-induced DNA damage through P53 pathway.

Platinum-based treatment causes Pt-DNA adducts which lead to cell death. The platinum-induced DNA damage is recognized and repaired by the nucleotide excision repair (NER) system of which ERCC2/XPD is a critical enzyme. Single nucleotide polymorphisms in ERCC2/XPD have been found to be associated with platinum resistance. The aim of the present study was to investigate whether ERCC2/XPD Lys751Gln (rs13181) polymorphism is causally related to DNA repair capacity of platinum-induced DNA damage. First, cDNA clones expressing different genotypes of the polymorphism was transfected to an ERCC2/XPD defective CHO cell line (UV5). Second, all cells were treated with cisplatin. Cellular survival rate were investigated by MTT growth inhibition assay, DNA damage levels were investigated by comet assay and RAD51 staining. The distribution of cell cycle and the change of apoptosis rates were detected by a flow cytometric method (FCM). Finally, P53mRNA and phospho-P53 protein levels were further investigated in order to explore a possible explanation. As expected, there was a significantly increased in viability of UV5ERCC2 (AA) as compared to UV5ERCC2 (CC) after cisplatin treatment. The DNA damage level of UV5ERCC2 (AA) was significant decreased compared to UV5ERCC2 (CC) at 24 h of treatment. Mutation of ERCC2rs13181 AA to CC causes a prolonged S phase in cell cycle. UV5ERCC2 (AA) alleviated the apoptosis compared to UV5ERCC2 (CC), meanwhile P53mRNA levels in UVERCC2 (AA) was also lower when compared UV5ERCC2 (CC). It co-incides with a prolonged high expression of phospho-P53, which is relevant for cell cycle regulation, apoptosis, and the DNA damage response (DDR). We concluded that ERCC2/XPD rs13181 polymorphism is possibly related to the DNA repair capacity of platinum-induced DNA damage. This functional study provides some clues to clarify the relationship between cisplatin resistance and ERCC2/XPDrs13181 polymorphism.

Genetic polymorphisms in 19q13.3 genes associated with alteration of repair capacity to BPDE-DNA adducts in primary cultured lymphocytes.

Benzo[a]pyrene(B[a]P), and its ultimate metabolite Benzo[a]pyrene 7,8-diol 9,10-epoxide (BPDE), are classic DNA damaging carcinogens. DNA damage in cells caused by BPDE is normally repaired by Nucleotide Excision Repair (NER) and Base Excision Repair (BER). Genetic variations in NER and BER can change individual DNA repair capacity to DNA damage induced by BPDE. In the present study we determined the number of in vitro induced BPDE-DNA adducts in lymphocytes, to reflect individual susceptibility to Polycyclic aromatic hydrocarbons (PAHs)-induced carcinogenesis. The BPDE-DNA adduct level in lymphocytes were assessed by high performance liquid chromatography (HPLC) in 281 randomly selected participants. We genotyped for 9 single nucleotide polymorphisms (SNPs) in genes involved in NER (XPB rs4150441, XPC rs2228001, rs2279017 and XPF rs4781560), BER (XRCC1 rs25487, rs25489 and rs1799782) and genes located on chromosome 19q13.2-3 (PPP1R13L rs1005165 and CAST rs967591). We found that 3 polymorphisms in chromosome 19q13.2-3 were associated with lower levels of BPDE-DNA adducts (MinorT allele in XRCC1 rs1799782, minor T allele in PPP1R13L rs1005165 and minor A allele in CAST rs967571). In addition, a modified comet assay was performed to further confirm the above conclusions. We found both minor T allele in PPP1R13L rs1005165 and minor A allele in CAST rs967571 were associated with the lower levels of BPDE-adducts. Our data suggested that the variant genotypes of genes in chromosome 19q13.2-3 are associated with the alteration of repair efficiency to DNA damage caused by Benzo[a]pyrene, and may contribute to enhance predictive value for individual's DNA repair capacity in response to environmental carcinogens.

ERCC1 and ERCC2 haplotype modulates induced BPDE-DNA adducts in primary cultured lymphocytes.

BACKGROUND: Benzo[a]pyrene(B[a]P), and its ultimate metabolite Benzo[a]pyrene 7,8-diol 9,10-epoxide (BPDE), are classic DNA damaging carcinogens. DNA damage caused by BPDE is normally repaired by Nucleotide Excision Repair (NER), of which ERCC1 and ERCC2/XPD exert an indispensable role. Genetic variations in ERCC1 and ERCC2 have been related to DNA repair efficiency. In this study we used lymphocytes from healthy individuals to show that polymorphisms in ERCC1 and ERCC2 are directly associated with decreased DNA repair efficiency. METHODS: ERCC1 (rs3212986 and rs11615) and ERCC2 (rs13181, rs1799793 and rs238406) were genotyped in 818 healthy Han individuals from the northeast of China. BPDE induced DNA adducts in lymphocytes were assessed by high performance liquid chromatography (HPLC) in 282 randomly selected participants. The effect of ERCC1 rs3212986 and ERCC2 rs238406 on DNA damage caused by B[a]P was assessed with a modified comet assay. RESULTS: We found that the variant genotypes of ERCC1 rs3212986 and ERCC2 rs238406 were associated with the high levels of BPDE-DNA adducts. Especially ERCC1 rs3212986 A-allele variant was significantly associated with the high BPDE-DNA adducts. Haplotype analysis showed that the ERCC1 haplotype AC (OR = 2.36, 95% CI = 1.84-2.97), ERCC2 haplotype AGA (OR = 1.51, 95% CI = 1.06-2.15) and haplotype block AGAAC (OR = 5.28, 95% CI = 2.95-9.43), AGCAC (OR = 1.35 95% CI = 1.13-1.60) were linked with high BPDE-DNA adducts. In addition, we found that the combined minor alleles of ERCC1 rs3212986 and ERCC2 rs238406 were associated with a reduced DNA repair capacity. CONCLUSIONS: Our results suggest that the variant genotypes of ERCC1 rs3212986 and ERCC2 rs238406 are associated with decreased repair efficiency of BPDE induced DNA damage, and may be predictive for an individual's DNA repair capacity in response to environmental carcinogens.

Association of genetic polymorphisms in ERCC1 and ERCC2/XPD with risk of chronic benzene poisoning in a Chinese occupational population.

DNA damage induced by benzene and its metabolites is thought of as an important mechanism underlying benzene genotoxicity in chronic benzene poisoning (CBP). Therefore, genetic variation in DNA repair genes may contribute to susceptibility to CBP in the exposed population. Since benzene-induced DNA damages include DNA adducts, we hypothesized that the polymorphisms of ERCC1 (Excision repair cross complementation group 1) and ERCC2/XPD (Excision repair cross complementation group 2/xeroderma pigmentosum group D) are associated with the risk of CBP. A case-control study involving 102 benzene-poisoned patients and 204 none-benzene-poisoned controls occupationally exposed to benzene was carried out in the Northeast region of China. The polymorphisms of codon 118 (rs11615) and C8092A (rs3212986) of ERCC1, codon 751 (rs13181), 312 (rs1799793) and 156 (rs238406) of ERCC2/XPD were genotyped by TaqMan(®) Real-time PCR. The results showed that individuals carrying the ERCC1 codon 118 TT genotype had an increased risk of CBP (OR(adj)=3.390; 95%CI: 1.393-8.253; P=0.007) comparing with its CC genotype. After stratified by smoking, gender and exposure duration we found that the increased risk of CBP associated with the ERCC1 codon 118 TT genotype confined to nonsmokers (OR=3.214; 95% CI: 1.359-7.601; P=0.006), female (OR=3.049; 95% CI: 1.235-7.529; P=0.013) and exposure duration> 12 years (OR=3.750; 95% CI: 1.041-13.513; P=0.035). Since ERCC1 and ERCC2/XPD are both located on chromosome 19q13.3, haplotype analysis of all 5 SNPs was also conducted. However no correlations between the risks of CBP and other genotypes or haplotypes were found. Therefore, our findings suggest an important role of ERCC1 codon 118 polymorphisms for a biomarker to CBP in the Chinese occupational population.

Prognostic significance of tumor deposits in gastric cancer patients who underwent radical surgery.

BACKGROUND: To investigate the prognostic significance of tumor deposits (TDs) in gastric cancers patients who underwent radical surgery. METHODS: Clinicopathologic and prognostic data from 2998 gastric cancer patients who underwent R0 surgery with D2/D3 lymphadenectomy were retrospectively reviewed. A TD was defined as discrete foci of tumor found in the perigastric fat or in adjacent ligament away from the leading edge of the tumor and showing no evidence of residual lymph node tissue, but within the lymph drainage area of the primary carcinoma. RESULTS: TDs were detected in 17.8% of patients. TDs were more frequently observed in cancers of larger size, of Borrmann type 4, with lymphovascular invasion, deeper in depth of invasion, and with extended lymph node metastasis. Multivariate analysis confirmed the presence of TDs as 1 of independent factors predicting a poorer outcome. When stratified by pN category, significant differences in survival were observed between patients with and without TDs for those in pN0/pT1-3, pN1/pT3, pN2/pT1-3 and pN3/pT2-3 category, but not for those in pT4a and pT4b category. Moreover, for cancers in each pN category, the prognosis for patients with TDs in pT1-4a category was similar with that of those without TDs in pT4a category, but significantly better than that of those with or without TDs in pT4b category. A revised pT category and a revised pTNM system were proposed, in which all the cancers with TDs in pT1-4a category were incorporated into those without TDs in pT4a category according to the pN category. Further analysis revealed the revised pT category and the revised pTNM system had better homogeneity, discriminatory ability, and monotonicity of gradients than the American Joint Committee on Cancer (AJCC) pT category and the AJCC pTNM system, respectively, representing optimum prognostic stratification. CONCLUSION: TDs significantly correlated with gastric cancer patients' survival. It might be more suitable for TDs to be treated as a form of serosal invasion. Consequently, en bloc resection of the primary carcinoma is crucially important, and adjuvant chemotherapy should always be considered if TDs have been detected.