Tumor-associated macrophages are a major constituent of malignant tumors and are known to stimulate key steps in tumor progression. In our review in this journal in 2006, we postulated that functionally distinct subsets of these cells exist in different areas within solid tumors. Here, we review the many experimental and clinical studies conducted since then to investigate the function(s), regulation, and clinical significance of macrophages in these sites. The latter include three sites of cancer cell invasion, tumor nests, the tumor stroma, and areas close to, or distant from, the tumor vasculature. A more complete understanding of macrophage diversity in tumors could lead to the development of more selective therapies to restore the formidable, anticancer functions of these cells. .

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Because malignant cells have altered, usually accelerated, energy consumption, targeting metabolic signaling represents a prevailing strategy for tumor therapy. Phosphoinositide-dependent kinase 1 (PDK1) is a proximal signaling molecule of phosphatidylinositol 3-kinase, which is required for metabolic activation. It is still lacking definitive evidence whether inactivation of PDK1 can overwhelm tumorigenesis in vivo. Herein we revealed that mammary-specific ablation of PDK1 could delay tumor initiation, progression and metastasis in a spontaneous mouse tumor model. We also demonstrated that inducible deletion of PDK1 could noticeably shrink the growing breast tumors. However, a small portion of PDK1-deficient tumorigenic cells eventually established tumor lesions, albeit at a relatively later phase, most likely owing to compensatory upregulation of extracellular signal-regulated kinase 1/2 (Erk1/2) phosphorylation. Consequently, simultaneous inhibition of PDK1 and Erk1/2 impeded the survival of breast cancer cells. Thus we identify PDK1 as a potential therapeutic target for breast cancer, particularly in combination with an Erk1/2 inhibitor.

ObjectiveMany studies have previously investigated the potential association between mobile phone use and the risk of glioma. However, results from these individual studies are inconclusive and controversial. The objective of our study was to investigate the potential association between mobile phone use and subsequent glioma risk using meta-analysis.MethodsWe performed a systematic search of the Science Citation Index Embase and PubMed databases for studies reporting relevant data on mobile phone use and glioma in 1980–2016. The data were extracted and measured in terms of the odds ratio (OR) and 95% confidence interval (CI) using the random effects model. Subgroup analyses were also carried out. This meta-analysis eventually included 11 studies comprising a total 6028 cases and 11488 controls.ResultsThere was a significant positive association between long-term mobile phone use (minimum, 10 years) and glioma (OR = 1.44, 95% CI = 1.08–1.91). And there was a significant positive association between long-term ipsilateral mobile phone use and the risk of glioma (OR = 1.46, 95% CI = 1.12–1.92). Long-term mobile phone use was associated with 2.22 times greater odds of low-grade glioma occurrence (OR = 2.22, 95% CI = 1.69–2.92). Mobile phone use of any duration was not associated with the odds of high-grade glioma (OR = 0.81, 95% CI = 0.72–0.92). Contralateral mobile phone use was not associated with glioma regardless of the duration of use. Similarly, this association was not observed when the analysis was limited to high-grade glioma.ConclusionsOur results suggest that long-term mobile phone use may be associated with an increased risk of glioma. There was also an association between mobile phone use and low-grade glioma in the regular use or long-term use subgroups. However, current evidence is of poor quality and limited quantity. It is therefore necessary to conduct large sample, high quality research or better characterization of any potential association between long-term ipsilateral mobile phone use and glioma risk.

The ETS family of transcription factors is involved in several physiological and pathological processes including tumor progression. The ETS transcription factors are divided into subfamilies based on the sequence and location of the ETS domain. ETV1 (Ets variant gene 1; also known as ER81), is a member of the PEA3 subfamily, which has been found to promote metastatic progression in several types of human cancer. Previous findings demonstrated that ETV1 expression is upregulated in gastric adenocarcinomas; however, the underlying mechanisms of ETV1-induced metastatic progression in gastric cancer remain elusive. In the present study, we found that the overexpression of ETV1 in normal gastric epithelial cells resulted in epithelial to mesenchymal transition (EMT) and increased invasiveness. Conversely, knockdown of ETV1 resulted in decreased aggressiveness of the invasive gastric cancer cells. Mechanistically, ETV1 transcriptionally upregulates Snail expression. Of note, ETV1 expression is significantly correlated with Snail expression in human gastric tumor samples. In summary, we present data that ETV1 promotes Snail expression to induce EMT-like metastatic progression in gastric cancer.