Chronic inflammation-associated genomic instability paves the way for human esophageal carcinogenesis

Serum Cytokines Correlate with Pretreatment Body Mass Index-adjusted Body Weight Loss Grading and Cancer Progression in Patients with Stage III Esophageal Squamous Cell Carcinoma Undergoing Neoadjuvant Chemoradiotherapy Followed by Surgery

Serum Cytokines Correlate with Pretreatment Body Mass Index-Adjusted Body Weight Loss Grading and Cancer Progression in Patients with Stage III Esophageal Squamous Cell Carcinoma Undergoing Neoadjuvant Chemoradiotherapy Followed by Surgery. Circulating cytokines have been linked to the development of esophageal squamous cell carcinoma (ESCC) and its associated malnutrition process. Nonetheless, given the varied disease stages and treatment modalities in previous studies, the clinical relevance of their findings is limited. We retrospectively studied 52 patients with stage III ESCC who underwent neoadjuvant chemoradiotherapy and curative-intent surgery. We investigated the association of clinicopathological features, pretreatment laboratory data, and pretreatment inflammatory status, as indicated by the levels of albumin, C-reactive protein, and 10 circulating cytokines, namely tumor necrosis factor-alpha (TNF-α), interferon-gamma, interleukin-1-beta (IL-1β), IL-4, IL-6, IL-8, IL-12, IL-13, IL-17A, and IL-23, with malnutrition, as shown by body mass index-adjusted body weight loss (BMI-BWL) grading, cancer progression. Half the patients showed severe malnutrition and high BMI-BWL grades (3 and 4). Multivariate analysis revealed an independent association between the levels of three cytokines (TNF-α, ≤ 5.8 pg/ml; IL-1β, > 0.4 pg/ml; IL-6, ≤ 12.4 pg/ml) and high BMI-BWL grades and between IL-4 levels > 22.5 pg/ml and cancer progression. All 10 cytokines were closely correlated with each other. In conclusion, TNF-α, IL-1β, and IL-6 were independent markers of malnutrition status and IL-4 was a prognostic factor for cancer progression in this patient population.

IL-1β transgenic mouse model of inflammation driven esophageal and oral squamous cell carcinoma

Chronic inflammation is integral to the development of esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC), although the latter has not been associated with reflux esophagitis. The L2-IL-1β transgenic mice, expressing human interleukin (IL)-1β in the oral, esophageal and forestomach squamous epithelia feature chronic inflammation and a stepwise development of Barrett's esophagus-like metaplasia, dysplasia and adenocarcinoma at the squamo-columnar junction. However, the functional consequences of IL-1β-mediated chronic inflammation in the oral and esophageal squamous epithelia remain elusive. We report for the first time that in addition to the previously described Barrett's esophagus-like metaplasia, the L2-IL-1β mice also develop squamous epithelial dysplasia with progression to squamous cell carcinoma (SCC) in the esophagus and the tongue. L2-IL-1β showed age-dependent progression of squamous dysplasia to SCC with approximately 40% (n = 49) and 23.5% (n = 17) incidence rates for esophageal and tongue invasive SCC respectively, by 12-15 months of age. Interestingly, SCC development and progression in L2-IL-1β was similar in both Germ Free (GF) and Specific Pathogen Free (SPF) conditions. Immunohistochemistry revealed a T cell predominant inflammatory profile with enhanced expression of Ki67, Sox2 and the DNA double-strand break marker, γ-H2AX, in the dysplastic squamous epithelia of L2-IL-1β mice. Pro-inflammatory cytokines, immunomodulatory players, chemoattractants for inflammatory cells (T cells, neutrophils, eosinophils, and macrophages) and oxidative damage marker, iNOS, were significantly increased in the esophageal and tongue tissues of L2-IL-1β mice. Our recent findings have expanded the translational utility of the IL-1β mouse model to aid in further characterization of the key pathways of inflammation driven BE and EAC as well as ESCC and Oral SCC.

Mastitis and Risk of Breast Cancer: a Case Control-Retrospective Study and Mini-Review

Objective: To investigate a possible association between mastitis and breast cancer risk in a cohort of Greek women. Material and methods:A series of 343 women who visited two breast clinics in Greece and delivered live neonates were studied in our case-control retrospective study. The case group comprised women with breast cancer and the control group women without breast cancer. All participants were subjected to a clinical examination with breast ultrasound and those aged over 40 years underwent digital bilateral mammography. Results:The χ2 (chi-square) test was the statistical tool used by us. We noted a statistically significant relationship between mastitis and risk for breast cancer (p=0.04). Moreover, the relative risk for breast cancer among patients with mastitis was RR: 2.069. Conclusion:Our study showed a relation between mastitis and breast cancer. Mastitis could be a potential risk factor. Further studies with larger number of patients are mandatory in order to confirm this possible relationship.

Potential Chemotherapeutic Effect of Selenium for Improved Canceration of Esophageal Cancer

Esophageal squamous cell carcinoma is the most common type of esophageal cancer and accounts for 5% of malignant tumor deaths. Recent research suggests that chronic inflammation and DNA damage may drive the onset of esophageal squamous cell carcinoma, implying that lowering chronic inflammation and DNA damage compounds may provide chemo-prevention. According to epidemiological and experimental evidence, selenium is linked to a lower risk of several malignancies, including esophageal squamous cell carcinoma. However, its exact mechanism is still unclear. In the present study, we used cell lines and a 4-NQO mice model to explore the anti-cancer mechanism of four types of selenium. Our findings indicated that selenium inhibited the proliferation, colony formation, and ROS level of ESCC cell lines in a time-dependent manner. Intriguingly, selenium treatment impeded 4-NQO-induced high-grade intraepithelial neoplasia and reduced the number of positive inflammatory cells by preserving DNA from oxidative damage. In addition, selenium significantly decreased the expression of Ki-67 and induced apoptosis. This study demonstrates that selenium has a significant chemo-preventive effect on ESCC by reducing high-grade dysplasia to low-grade dysplasia. For the first time, selenium was shown to slow down the progression of esophageal cancer by lowering inflammation and oxidative DNA damage.

Alimentary squamous cell carcinoma in psittacines: 12 cases and review of the literature

Squamous cell carcinoma (SCC), which is a neoplasm that usually arises from the integument, is reported uncommonly in pet birds. Only a few reports of SCCs in the alimentary tract of birds, including psittacines, have been published, and a detailed description of the pathology is not available in the literature. We present here 12 cases of alimentary SCC in psittacines. The average age of the birds was 22.2 y (range: 15-29 y), and affected species included 4 Amazon parrots (Amazona sp.), 3 cockatiels (Nymphicus hollandicus), 3 macaws (Ara sp.), 1 conure (Eupsittula sp.), and 1 Senegal parrot (Poicephalus sp.). Frequent clinical complaints included regurgitation, dysphagia, dyspnea, lethargy, and/or weight loss. SCC primarily affected the oral cavity in 6 of 12 cases, the crop alone in 2 of 12 cases, the crop and esophagus in 1 of 12 cases, the proventriculus alone in 1 of 12 cases, and the crop, esophagus, and proventriculus in 2 of 12 cases. Histologically, alimentary SCCs were locally invasive and often resulted in mucosal ulceration. Although there were no metastases in any of our cases, poor clinical outcomes were frequent and associated most commonly with complete effacement of the alimentary segment and severe inflammation with opportunistic bacterial infection. Our review of the literature records commonly affected species, variability of gross presentations and clinical signs, plausible etiologies, and current diagnostic developments.

Obesity-Associated Myeloid Immunosuppressive Cells, Key Players in Cancer Risk and Response to Immunotherapy

Obesity is a risk factor for developing several cancers. The dysfunctional metabolism and chronic activation of inflammatory pathways in obesity create a milieu that supports tumor initiation, progression, and metastasis. Obesity-associated metabolic, endocrine, and inflammatory mediators, besides interacting with cells leading to a malignant transformation, also modify the intrinsic metabolic and functional characteristics of immune myeloid cells. Here, the evidence supporting the hypothesis that obesity metabolically primes and promotes the expansion of myeloid cells with immunosuppressive and pro-oncogenic properties is discussed. In consequence, the accumulation of these cells, such as myeloid-derived suppressor cells and some subtypes of adipose-tissue macrophages, creates a microenvironment conducive to tumor development. In this review, the role of lipids, insulin, and leptin, which are dysregulated in obesity, is emphasized, as well as dietary nutrients in metabolic reprogramming of these myeloid cells. Moreover, emerging evidence indicating that obesity enhances immunotherapy response and hypothesized mechanisms are summarized. Priorities in deeper exploration involving the mechanisms of cross talk between metabolic disorders and myeloid cells related to cancer risk in patients with obesity are highlighted.

Integrative analysis of differential circular RNA and long non-coding RNA profiles and associated competing endogenous RNA networks in esophageal squamous cell carcinoma

Long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) play vital roles in the tumorigenesis of esophageal squamous cell carcinoma (ESCC). Nevertheless, the mechanism and regulatory network associated with this process remain largely unknown. In this study, we performed a comprehensive analysis of the expression of mRNAs, lncRNAs, and circRNAs by RNA-seq. A total of 3265 mRNAs, 1084 lncRNAs, and 38 circRNAs were found to be differentially expressed. Among these, 269 mRNAs were found to encode transcription factors (TFs). Functional enrichment analysis indicated that the dysregulated TFs are associated with the Hedgehog, Jak-STAT, TGF-beta, and MAPK signaling pathways. Furthermore, we constructed co-expression networks to screen the core lncRNAs and circRNAs involved in the regulation of transcription factors in these four pathways. Finally, we constructed a competing endogenous RNA (ceRNA) network of ESCC based on the abovementioned pathways. Our findings provide important insight into the role of lncRNAs and circRNAs in ESCC; the differentially expressed lncRNAs and circRNAs may represent potential targets for ESCC diagnosis and therapy.

Redox tolerance and metabolic reprogramming in solid tumors

Tumor cells need to cope with the host environment for survival and keep growing in hard conditions. This suggests that tumors must acquire characteristics more potent than what is seen for normal tissue cells, without which they are condemned to disruption.  For example, cancer cells have more potent redox tolerance compared with normal cells, which is due to their high adaptation to an oxidative crisis. In addition, increased demand for bioenergetics and biosynthesis can cause a rise in nutrient uptake in tumors. Utilizing nutrients in low nutrient conditions suggests that tumors are also equipped with adaptive metabolic processes. Switching the metabolic demands toward glucose consumption upon exposure to the hypoxic tumor microenvironment, or changing toward using other sources when there is an overconsumption of glucose in the tumor area are examples of fitness metabolic systems in tumors. In fact, cancer cells in cooperation with their nearby stroma (in a process called metabolic coupling) can reprogram their metabolic systems in their favor. This suggests the high importance of stroma for meeting the metabolic demands of a growing tumor, an example in this context is the metabolic symbiosis between cancer-associated fibroblasts with cancer cells. The point is that redox tolerance and metabolic reprogramming are interrelated, and that, without a doubt, disruption of redox tolerance systems by transient exposure to either oxidative or antioxidative loading, or targeting metabolic rewiring by modulation of tumor glucose availability, controlling tumor/stroma interactions, etc. can be effective from a therapeutic standpoint.

Clinical implications of the preoperative lymphocyte C-reactive protein ratio in esophageal cancer patients

PURPOSE

We recently revealed the preoperative lymphocyte C-reactive protein ratio (LCR) to be a new marker for predicting various outcomes in malignancies. The aim of our present study was to clarify the potential utility of the preoperative LCR for predicting the perioperative risk and oncological outcome in esophageal cancer patients.

METHODS

We analyzed the preoperative LCR from 153 esophageal cancer patients to clarify its clinical relevance.

RESULTS

The preoperative LCR was significantly decreased in a stage-dependent manner, and a decreased preoperative LCR was significantly associated with the occurrence of postoperative surgical site infection. Esophageal cancer patients with a low LCR showed a poor outcome in both the overall survival and disease-free survival compared with those who had a high LCR. Multivariate analyses showed that a decreased LCR was an independent prognostic factor for both a poor overall survival and disease-free survival. A decreased preoperative LCR was an independent predictive factor for postoperative surgical site infection and significantly correlated with nutritional and inflammatory indicators. In addition, the LCR was useful for identifying esophageal cancer patients likely to have a poor outcome among patients with and without neoadjuvant chemotherapy.

CONCLUSIONS

Assessing the preoperative LCR might help physicians identify populations at high risk for perioperative complication and oncological outcomes, and determine individualized perioperative therapeutic strategies.

Proposed hypothesis and rationale for association between mastitis and breast cancer

Breast cancer is amongst the most common forms of cancer, is predominantly a woman's illness, and is the most frequently reported invasive cancer in women worldwide (Bray et al., 2018). Varying risk factors have been identified, including genetics, family history, lifestyle, age and the use of hormone replacement therapy. Mastitis, also predominantly a woman's illness, is an inflammatory condition of the breast that, despite being an inflammation-related condition, is not currently considered a risk factor for breast cancer. This appears counterintuitive as epidemiological studies have identified chronic inflammation as a contributor to cancer risk, for example in gastric, oesophageal and colon cancers (Lin et al., 2016; Qadri et al., 2014; Principe et al., 2017). Previous reports have focused on women hospitalised for mastitis, and most commonly on puerperal mastitis, perhaps underestimating the relationship between breast cancer and non-lactational mastitis. Our hypothesis, based on systematic review, suggests that a longitudinal study of this disease, affecting women predominantly, is warranted.

Association of C-reactive protein (CRP) rs1205 and rs2808630 variants and risk of cancer

The correlation between rs1205, rs2808630 variants of C-reactive protein (CRP) gene and susceptibility of cancer has been assessed previously, but with conflicting results. We adopted odds ratios (ORs) with 95% confidence intervals (CIs), in silico tools and enzyme-linked immunosorbent assay (ELISA) analysis to evaluate this association. Totally, 10,614 cancer subjects and 33,294 controls were involved in the pooled analysis. When all the studies were pooled, no significant correlation was indicated between the two variants and cancer risk. However, in stratification analysis by ethnicity, we found that CRP rs1205 C>T polymorphism was associated with an elevated risk of cancer in Asians (T-allele vs. C-allele, OR = 1.20, 95% CI = 1.06-1.36, p_{heterogeneity}  = .226; TT vs. CC, OR = 1.48, 95% CI = 1.14-1.93, p_{heterogeneity}  = .089). Similar findings were observed for rs2808630 variant. In silico tools showed that lung adenocarcinoma participants with high CRP expression may have shorter overall survival time than low expression group. ELISA analysis indicated that CRP expression in prostate adenocarcinoma subjects with TT + TC genotypes was statistically higher than in those with CC genotypes. CRP rs1205 C>T and rs2808630 T>C polymorphism may be associated with cancer risk, especially for Asians.

Tumor Immunology and Tumor Evolution: Intertwined Histories

Cancer is a complex disease whose outcome depends largely on the cross-talk between the tumor and its microenvironment. Here, we review the evolution of the field of tumor immunology and the advances, in lockstep, of our understanding of cancer as a disease. We discuss the involvement of different immune cells at distinct stages of tumor progression and how immune contexture determinants shaping tumor development are being exploited therapeutically. Current clinical stratification schemes focus on the tumor histopathology and the molecular characteristics of the tumor cell. We argue for the importance of revising these stratification systems to include immune parameters so as to address the immediate need for improved prognostic and/or predictive information to guide clinical decisions.

IL1R2 Polymorphisms are Associated with Increased Risk of Esophageal Cancer

BACKGROUND

Esophageal cancer (EC) is the sixth leading cause of cancer death worldwide, and the overall incidence is increasing.

OBJECTIVE

The aim of this study was to evaluate the association between single nucleotide polymorphisms in IL1R2 and EC risk in the Chinese population.

METHODS

Genotyping of six SNPs of IL1R2 was performed with the Agena MassARRAY platform from 384 EC and 499 controls. The association between polymorphisms and EC risk was assessed by performing genetics models and haplotype analyses.

RESULTS

Overall analysis results showed that the allele C of rs11674595 (odds ratio [OR] = 1.42, 95% confidence interval [CI]: 1.14-1.77, p = 0.002) and allele G of rs2072472 (allele: OR = 1.35, 95% CI: 1.08-1.69, p = 0.008) were associated with an increased EC risk. The rs11674595 and rs2072472 were found to be correlated with EC risk under the codominant, dominant, and additive models. Stratification analysis found that rs11674595 and rs2072472 were associated with increased EC risk in male and in age > 55 years old subgroup. In addition, Crs11674595Grs4851527 haplotype was significantly associated with 1.44-fold increased risk of EC (95% CI: 1.12-1.84, p = 0.004).

CONCLUSION

Our results reveal the significant association between SNPs (rs11674595 and rs2072472) in the IL1R2 and EC risk in the Chinese Han population. The findings may provide meaningful reference for the prevention and treatment of EC.

Microglia and the aging brain: are senescent microglia the key to neurodegeneration?

The single largest risk factor for etiology of neurodegenerative diseases like Alzheimer's disease is increased age. Therefore, understanding the changes that occur as a result of aging is central to any possible prevention or cure for such conditions. Microglia, the resident brain glial population most associated with both protection of neurons in health and their destruction is disease, could be a significant player in age related changes. Microglia can adopt an aberrant phenotype sometimes referred to either as dystrophic or senescent. While aged microglia have been frequently identified in neurodegenerative diseases such as Alzheimer's disease, there is no conclusive evidence that proves a causal role. This has been hampered by a lack of models of aged microglia. We have recently generated a model of senescent microglia based on the observation that all dystrophic microglia show iron overload. Iron-overloading cultured microglia causes them to take on a senescent phenotype and can cause changes in models of neurodegeneration similar to those observed in patients. This review considers how this model could be used to determine the role of senescent microglia in neurodegenerative diseases.

IL-4 and IL-17A Cooperatively Promote Hydrogen Peroxide Production, Oxidative DNA Damage, and Upregulation of Dual Oxidase 2 in Human Colon and Pancreatic Cancer Cells

Dual oxidase 2 (DUOX2) generates H₂O₂ that plays a critical role in both host defense and chronic inflammation. Previously, we demonstrated that the proinflammatory mediators IFN-γ and LPS enhance expression of DUOX2 and its maturation factor DUOXA2 through STAT1- and NF-κB‒mediated signaling in human pancreatic cancer cells. Using a panel of colon and pancreatic cancer cell lines, we now report the induction of DUOX2/DUOXA2 mRNA and protein expression by the T_H2 cytokine IL-4. IL-4 activated STAT6 signaling that, when silenced, significantly decreased induction of DUOX2. Furthermore, the T_H17 cytokine IL-17A combined synergistically with IL-4 to increase DUOX2 expression in both colon and pancreatic cancer cells mediated, at least in part, by signaling through NF-κB. The upregulation of DUOX2 was associated with a significant increase in the production of extracellular H₂O₂ and DNA damage-as indicated by the accumulation of 8-oxo-dG and γH2AX-which was suppressed by the NADPH oxidase inhibitor diphenylene iodonium and a DUOX2-specific small interfering RNA. The clinical relevance of these experiments is suggested by immunohistochemical, microarray, and quantitative RT-PCR studies of human colon and pancreatic tumors demonstrating significantly higher DUOX2, IL-4R, and IL-17RA expression in tumors than in adjacent normal tissues; in pancreatic adenocarcinoma, increased DUOX2 expression is adversely associated with overall patient survival. These data suggest a functional association between DUOX2-mediated H₂O₂ production and induced DNA damage in gastrointestinal malignancies.

Association Between ERCC1 rs3212986 and ERCC2/XPD rs1799793 and OS in Patients With Advanced Esophageal Cancer

Esophageal cancer (EC) is a very aggressive tumor, and no reliable prognostic markers exist especially for resectable advanced neoplasia. The principal aim of this study was to investigate the association of germline polymorphisms in nucleotide excision repair (NER) pathway genes with the overall survival (OS) of patients with advanced EC. As a second aim, we also studied the association of NER gene variants with response to cisplatin-based chemotherapy. Among the EC patients referred to our Institution between 2004 and 2012, we selected a cohort of 180 patients diagnosed with a clinical tumor stage ranging from IIB and IVA. Patients were genotyped for four NER variants, two in the ERCC1 (rs11615 and rs3212986) and two in the ERCC2/XPD (rs1799793 and rs13181) genes. Kaplan–Meier analyses and Cox proportional hazards model were used to evaluate the associations of the selected variants with OS; association with response to neoadjuvant therapy was investigated using logistic regression. Results showed that the ERCC1 rs3212986 and the ERCC2/XPD rs1799793 were significantly associated with shorter OS. On the contrary, response association analysis displayed that, while rs11615 and rs3212986 in ERCC1 were associated with response, both ERCC2/XPD variants were not. By creating survival prediction models, we showed that the rs3212986 and the rs1799793 have a better predictability of the tumor stage alone. Furthermore, they were able to improve the power of the clinical model (AUC = 0.660 vs. AUC = 0.548, p = 0.004). In conclusion, our results indicate that the ERCC1 rs3212986 and the ERCC2/XPD rs1799793 could be used as surrogate markers for a better stratification of EC patients with advanced resectable tumor.

Dietary riboflavin deficiency promotes N-nitrosomethylbenzylamine-induced esophageal tumorigenesis in rats by inducing chronic inflammation

Epidemiological studies in high-incidence areas of esophageal cancer in China suggest that environmental carcinogen N-nitrosomethylbenzylamine (NMBA) and riboflavin (RBF) deficiency may be the main risk factors for esophageal cancer. However, it is not clear that the combination induces cancer. Here, experiment (Exp) 1 evaluated the effects of NMBA and RBF deficiency individually or in combination on esophageal tumorigenesis. Male F344 rats were randomly assigned to 4 groups into a 2 (no NMBA vs. NMBA) × 2 (normal RBF vs. RBF-deficient) factorial design, including normal RBF (6 mg/kg, R₆), RBF-deficient (0 mg/kg, R₀), normal RBF combined with NMBA (R₆N), and RBF-deficient combined with NMBA (R₀N) groups. The Exp 2 explored the effects of RBF deficiency at different doses combined with NMBA (0.6 mg/kg, R_0.6N; 0.06 mg/kg, R_0.06N) on esophageal tumorigenesis. Results showed that R₀N enhanced the incidence of esophageal intraepithelial neoplasia (EIN, 53.3%, P = 0.06), including carcinoma in situ, whereas R₆N mainly induced the occurrence of esophageal benign hyperplasia (38.9%) and EIN (16.7%). RBF deficiency promotes EIN in a dose-dependent manner, and R_0.06N significantly increases the incidence of EIN (57.9%, P < 0.05). Gene expression profiling demonstrated that inflammatory cytokines were highly expressed in R₀N EIN tissues, whereas R₆N EIN tissues had a proliferation and differentiation gene signature (fold-change > 1.5). Furthermore, RBF deficiency aggravated oxidative DNA damage (8-OHdG) and double-strand breaks (γH2AX) (P < 0.05). Our results suggest that RBF deficiency causes chronic inflammation-associated genomic instability contributes to NMBA-induced esophageal tumorigenesis.

miR-302b inhibits cancer-related inflammation by targeting ERBB4, IRF2 and CXCR4 in esophageal cancer

Cancer related inflammation (CRI) plays an important role in the development of esophageal cancer (EC), and the target gene analysis shows that miR-302b potential target genes closely correlated to CRI important signaling pathways. The present study was to evaluate the inhibition of miR-302b on CRI in EC and its mechanism. We found that the expression levels of miR-302b in EC cells were lower than that in Het-1A cells, while TE11 with the lowest expression and OE33 with the highest. Inflammatory stimuli at 48 h significantly reduced expression of miR-302b in EC cells, but had no effect in Het-1A. After up-regulation of miR-302b in TE11 and down-regulation of miR-302b in OE33, it was found that miR-302b reduced CRI key transcription factors and representative cytokines. Then, over-expressed of miR-302b significantly altered potential target genes protein expressions and there was a negative correlation between miR-302b and potential target genes protein expressions (ERBB4, IRF2 and CXCR4) in EC tissues. Then reporter gene analysis revealed that miR-302b post-transcriptionally regulated expression of target genes by specific area of 3′-UTR. Transfected by target genes shRNA plasmids together could get the same effects of miR-302b on protein expression of CRI key transcription factors. Furthermore, miR-302b was able to repress tumor growth and transcription factors protein expression in vivo. These finding suggests that miR-302b inhibits key transcription factors and cytokines by targeting ERBB4, IRF2 and CXCR4, implicating its role in the inhibition of CRI in EC.

Immunological Approaches Towards Cancer and Inflammation: A Cross Talk

The inflammation is the protective response of the body against various harmful stimuli; however, the aberrant and inappropriate activation tends to become harmful. The acute inflammatory response tends to resolved once the offending agent is subside but this acute response becomes chronic in nature when the body is unable to successfully neutralized the noxious stimuli. This chronic inflammatory microenvironment is associated with the release of various pro-inflammatory and oncogenic mediators such as nitric oxide (NO), cytokines [IL-1β, IL-2, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)], growth factor, and chemokines. These mediators make the inflammatory microenvironment more vulnerable toward tumorigenesis. The pro-inflammatory mediators released during the chronic inflammation tends to induce several molecular signaling cascades such as nuclear factor kappa B, MAPKinase, nuclear factor erythroid 2-related factor 2, phosphoinositide-3-kinase, Janus kinases/STAT, Wnt/B-catenin, and cyclic AMP response element binding protein. The immune system and its components have a pleiotropic effect on inflammation and cancer progression. Immune components such as T cells, natural killer cells, macrophages, and neutrophils either inhibit or enhance tumor initiation depending on the type of tumor and immune cells involved. Tumor-associated macrophages and tumor-associated neutrophils are pro-tumorigenic cells highly prevalent in inflammation-mediated tumors. Similarly, presence of T regulatory (Treg) cells in an inflammatory and tumor setting suppresses the immune system, thus paving the way for oncogenesis. However, Treg cells also inhibit autoimmune inflammation. By contrast, cytotoxic T cells and T helper cells confer antitumor immunity and are associated with better prognosis in patients with cancer. Cytotoxic T cells inflict a direct cytotoxic effect on cells expressing oncogenic markers. Currently, several anti-inflammatory and antitumor therapies are under trials in which these immune cells are exploited. Adoptive cell transfer composed of tumor-infiltrating lymphocytes has been tried for the treatment of tumors after their ex vivo expansion. Mediators released by cells in a tumorigenic and inflammatory microenvironment cross talk with nearby cells, either promoting or inhibiting inflammation and cancer. Recently, several cytokine-based therapies are either being developed or are under trial to treat such types of manifestations. Monoclonal antibodies directed against TNF-α, VEGF, and IL-6 has shown promising results to ameliorate inflammation and cancer, while direct administration of IL-2 has been shown to cause tumor regression.

Metformin: Prevention of genomic instability and cancer: A review

The diabetes drug metformin can mitigate the genotoxic effects of cytotoxic agents and has been proposed to prevent or even cure certain cancers. Metformin reduces DNA damage by mechanisms that are only incompletely understood. Metformin scavenges free radicals, including reactive oxygen species and nitric oxide, which are produced by genotoxicants such as ionizing or non-ionizing radiation, heavy metals, and chemotherapeutic agents. The drug may also increase the activities of antioxidant enzymes and inhibit NADPH oxidase, cyclooxygenase-2, and inducible nitric oxide synthase, thereby limiting macrophage recruitment and inflammatory responses. Metformin stimulates the DNA damage response (DDR) in the homologous end-joining, homologous recombination, and nucleotide excision repair pathways. This review focuses on the protective properties of metformin against genomic instability.

Constitutive activated STAT3 is an essential regulator and therapeutic target in esophageal squamous cell carcinoma

Esophageal carcinoma is among the most common cancers worldwide and a leading cause of cancer death [1]. Large numbers of studies indicated that chronic inflammation is closely associated with its development [21, 25]. Furthermore, the JAK/STAT pathway, which plays a critical role in inflammation and immunity, has been implied in a number of malignancies [11]. It has been shown that targeting the pathway affected the growth, apoptosis, and metastasis of cultured esophageal squamous cell carcinoma cells [26]. We found in the present study that STAT3 is constitutively activated in a subgroup of esophageal squamous cell carcinoma cell lines and primary tumors. Altered expressions of STAT3 target genes were found in these tumors by using RNAseq and qPCR analysis. Cytokines that activate STAT3 affected the expression of STAT3 target genes and promoted the growth of the ESCC cells, which could be blocked by STAT3 inhibitor and specific siRNA. Inhibition of STAT3 also suppressed the growth and colony formation, and induced apoptosis in the esophageal squamous cell carcinoma cells containing constitutively activated STAT3. Furthermore, the STAT3 inhibitor effectively blocked the growth of patient-derived tumor xenografts that harbored phosphorylated STAT3, but acted less effective on the xenografts derived from primary tumors that contained low levels of activated STAT3. These results indicated that activated STAT3 plays a critical role in the survival and growth of a subgroup of esophageal squamous cell carcinoma, and may serve as a target for precision therapeutic intervention.

Suppressor of cytokine signaling-1 gene therapy induces potent antitumor effect in patient-derived esophageal squamous cell carcinoma xenograft mice

Chronic inflammation is involved in cancer growth in esophageal squamous cell carcinoma (ESCC), which is a highly refractory cancer with poor prognosis. This study investigated the antitumor effect and mechanisms of SOCS1 gene therapy for ESCC. Patients with ESCC showed epigenetics silencing of SOCS1 gene by methylation in the CpG islands. We infected 10 ESCC cells with an adenovirus-expressing SOCS1 (AdSOCS1) to examine the antitumor effect and mechanism of SOCS1 overexpression. SOCS1 overexpression markedly decreased the proliferation of all ESCC cell lines and induced apoptosis. Also, SOCS1 inhibited the proliferation of ESCC cells via multiple signaling pathways including Janus kinase (JAK)/signal transducer and activator of transcription (STAT) and focal adhesion kinase (FAK)/p44/42 mitogen-activated protein kinase (p44/42 MAPK). Additionally, we established two xenograft mouse models in which TE14 ESCC cells or ESCC patient-derived tissues (PDX) were subcutaneously implanted. Mice were intra-tumorally injected with AdSOCS1 or control adenovirus vector (AdLacZ). In mice, tumor volumes and tumor weights were significantly lower in mice treated with AdSOCS1 than that with AdLacZ as similar mechanism to the in vitro findings. The Ki-67 index of tumors treated with AdSOCS1 was significantly lower than that with AdLacZ, and SOCS1 gene therapy induced apoptosis. These findings demonstrated that overexpression of SOCS1 has a potent antitumor effect against ESCC both in vitro and in vivo including PDX mice. SOCS1 gene therapy may be a promising approach for the treatment of ESCC.

Prognostic significance of the lymphocyte-to-monocyte ratio and the tumor-infiltrating lymphocyte to tumor-associated macrophage ratio in patients with stage T3N0M0 esophageal squamous cell carcinoma

PURPOSE

We assessed the prognostic significance of, and the relationship between, the pretreatment lymphocyte-to-monocyte ratio (LMR) and the TILs/tumor-associated macrophages (TAMs) ratio, in patients with esophageal squamous cell carcinoma (ESCC) of pathological stage T3N0M0 (pT3N0M0).

METHODS

A total of 220 newly diagnosed ESCC patients of stage pT3N0M0 who had not undergone neoadjuvant therapy were included. Densities of CD8+ TILs, CD4+ TILs, CD45RO+ TILs, and CD68+ TAMs were assessed by immunohistochemical staining of tissue microarray cores from all 220 pT3N0M0 ESCC patients (who underwent radical resection). Hematological biomarkers including lymphocyte and monocyte counts were obtained from routine preoperative blood test data, and the LMR and TILs/TAMs ratios calculated. Cutoff finder for survival prediction was plotted to find out the optimal cutoff point for each parameter.

RESULTS

The LMR and TILs/TAMs ratios were interrelated. On univariate analyses of data from the entire cohort, the LMR, CD45RO/CD68 ratio, and CD8/CD68 ratio were significantly associated with both OS and disease-free survival. Only the CD45RO/CD68 ratio was independently prognostic of survival on multivariate analysis.

CONCLUSIONS

The prognostic significance of the CD45RO/CD68 ratio was higher than that of the LMR. The CD45RO/CD68 ratio is a useful independent prognostic marker in patients with pT3N0M0 ESCC who have undergone complete resection without neoadjuvant therapy.