Background.: Complications from skeletal-related events (SREs) constitute a challenge in the care of cancer patients with bone metastasis (BM). Objectives.: This study evaluated the comparative effectiveness of pamidronate, ibandronate, zoledronate, and denosumab in reducing the morbidity of SREs in cancer patients with BM. Methods.: Medline (1948 to January 2014), Embase (1980 to January 2014), the Cochrane Library (2014 issue 1), and Web of Science with Conference Proceedings (1970 to January 2014) were searched. Only randomized controlled trials assessing denosumab, bisphosphonates, or placebo in cancer patients with BM were included. The primary outcomes were SREs and SREs by type. The network meta-analysis (NMA) was performed with a random-effects Bayesian model. Results.: The NMA included 14 trials with 10,192 patients. Denosumab was superior to placebo in reducing the risk of SREs (odds ratio [OR]: 0.49; 95% confidence interval [CI]: 0.31–0.75), followed by zoledronate (OR: 0.57; 95% CI: 0.41–0.77) and pamidronate (OR: 0.55; 95% CI: 0.41–0.72). Ibandronate compared with placebo could not reduce the risk of SREs. Denosumab was superior to placebo in reducing the risk of pathologic fractures (OR: 0.50; 95% CI: 0.32–0.79), followed by zoledronate (OR: 0.61; 95% CI: 0.43–0.86). Denosumab was superior to placebo in reducing the risk of radiation (OR: 0.51; 95% CI: 0.35–0.75), followed by pamidronate (OR: 0.67; 95% CI: 0.52–0.86) and zoledronate (OR: 0.70; 95% CI: 0.52–0.96). Conclusion.: This NMA showed that denosumab, zoledronate, and pamidronate were generally effective in preventing SREs in cancer patients with BM. Denosumab and zoledronate were also associated with reductions in the risk of pathologic fractures and radiation compared with placebo. Denosumab was shown to be the most effective of the bone-targeted agents.
Despite recent advances in targeted and immune‐based therapies, the poor prognosis of lung adenocarcinoma (LUAD) with bone metastasis (BM) remains a challenge. First, two‐dimensional gel electrophoresis (2‐DE) was used to identify proteins that were differentially expressed in LUAD with BM, and then matrix‐assisted laser desorption/ionization time of flight mass spectrometry (MALDI‐TOF‐MS) was used to identify these proteins. Second, the Cancer Genome Atlas (TCGA) was used to identify mutations in these differentially expressed proteins and Kaplan–Meier plotter (KM Plotter) was used to generate survival curves for the analyzed cases. Immunohistochemistry (IHC) was used to check the expression of proteins in 28 patients with BM and nine patients with LUAD. Lastly, the results were analyzed with respect to clinical features and patient's follow‐up. We identified a number of matched proteins from 2‐DE. High expression of enolase 1 (ENO1) (HR = 1.67, logrank P = 1.9E‐05), ribosomal protein lateral stalk subunit P2 (RPLP2) (HR = 1.77, logrank P = 2.9e‐06), and NME/NM23 nucleoside diphosphate kinase 2 (NME1‐NME2) (HR = 2.65, logrank P = 3.9E‐15) was all significantly associated with poor survival (P <0.05). Further, ENO1 was upregulated (P =0.0004) and calcyphosine (CAPS1) was downregulated (P =5.34E‐07) in TCGA LUAD RNA‐seq expression data. IHC revealed that prominent ENO1 staining (OR = 7.5, P =0.034) and low levels of CAPS1 (OR = 0.01, P <0.0001) staining were associated with BM incidence. Finally, we found that LUAD patients with high expression of ENO1 and RPLP2 had worse overall survival. This is the first instance where the genes ENO1, RPLP2, NME1‐NME2 and CAPS1 were associated with disease severity and progression in LUAD patients with BM. Thus, with this study, we have identified potential biomarkers and therapeutic targets for this disease.
Cancer-associated fibroblasts (CAF) constitute a major component of the tumor microenvironment. The effects of CAFs on the progression of colorectal cancer remain controversial. In this study, we found the ectopic overexpression of Fibronectin leucine-rich transmembrane protein 3 (FLRT3) inhibited the process of epithelial–mesenchymal transition (EMT), as well as the proliferation, migration, invasion, and promote apoptosis of colorectal cancer cells, whereas silencing FLRT3 expression resulted in the opposite phenomenon. FLRT3 downregulation was associated with a poor prognosis in colorectal cancer. Also, FLRT3 expression was significantly related to some clinicopathologic factors, including T stage (P = 0.037), N stage (P = 0.042), and E-cadherin (P = 0.002) level. Via univariate and multivariate analyses, M stage (P < 0.0001), FLRT3 (P = 0.044), and E-cadherin (P = 0.003) were associated with overall survival and were independent prognostic factors for it. Mechanistically, CAFs secreted TGF-β, which downregulated FLRT3 expression by activating SMAD4 to promote aggressive phenotypes in colorectal cancer cells. Moreover, FLRT3 repressed tumorigenesis and lung metastasis, which could be reversed by LY2109761, a dual inhibitor of TGF-β receptor type I and II. Treatment with LY2109761 increased IFN-γ expression in CD8+ T cells and reduced the number of regulatory T cells in the tumor microenvironment. Taken together, we revealed the metastasis-suppressive function of FLRT3, which was attenuated during the CAFs-mediated activation of the TGF-β/SMAD4 signaling pathway to promote EMT in colorectal cancer. LY2109761 that significantly inhibited metastasis could be a new treatment option for advanced colorectal cancer. Implications: CAFs enhance colorectal cancer aggressiveness by reducing FLRT3 expression through activating TGF-β/SMAD4 signaling pathway. CAF-targeted therapy and/or LY2109761 were promising treatments for colorectal cancer.
Bone metastasis (BM) dramatically reduces the quality of life and life expectancy in lung adenocarcinoma (LUAD) patients. There is an urgent need to identify potential biomarkers for application in the treatment of this deadly disease. We compared patient BM, LUAD, and para-LUAD tissues using proteomic analysis and identified aldehyde dehydrogenase 2 (ALDH2), which can detoxify acetaldehyde to acetic acid, as one of the key regulators in lung tumor metastasis. Both the mRNA and protein levels of ALDH2 were significantly lower in tumor tissues than in normal tissues and were lowest in BM tissues with increased migratory capacity. Also, ALDH2 was upregulated following treatment with 5-azacitidine, a DNA methyltransferase inhibitor, in H1299, H460, and HCC827 cells. Further, we identified a potential methylated CpG island 3, with the longest methylated CpG island area in ALDH2, and performed bisulfite genomic sequencing of these sites. An average of 78.18% of the sites may be methylated in CpG island 3. Knockdown of DNA (cytosine-5)-methyltransferase 3A (DNMT3A) and methylated CpG binding protein 4 (MBD4) upregulated ALDH2 expression. ALDH2 functions as a mitogen-activated protein kinase (MAPK) upstream to inhibit cell proliferation and migration, promote cell apoptosis, and alter the epithelial–mesenchymal transition (EMT) by elevating E-cadherin and attenuating vimentin. Cell proliferation and migration were inhibited after the addition of the JNK inhibitor SP600125. In the multivariate analysis, M stage (p = 0.003), ALDH2 (p = 0.008), and phospho-c-Jun N-terminal kinase (p-JNK) (p = 0.027) expression were independent prognostic factors for overall survival in patients with BM. In vivo experiments also showed that ALDH2 expression could suppress tumor formation. In summary, we found that ALDH2 expression is a prognostic factor for BM in LUAD and that DNMT3A and MBD4 repression of ALDH2 via a MAPK-dependent pathway alters the EMT process, indicating that these proteins could act as potential biomarkers or therapeutic targets for LUAD metastasis.