The expression and role of CXC chemokines in colorectal cancer

Cancer is a life-threatening disease world-wide and colorectal cancer is the second common cause of cancer mortality. The interaction between tumor cells and stromal cells plays a crucial role in tumor initiation and progression and is partially mediated by chemokines. Chemokines predominantly participate in the chemoattraction of leukocytes to inflammatory sites. Nowadays, it is clear that CXC chemokines and their receptors (CXCR) may also modulate tumor behavior by several important mechanisms: regulation of angiogenesis, activation of a tumor-specific immune response by attracting leukocytes, stimulation of tumor cell proliferation and metastasis. Here, we review the expression and complex roles of CXC chemokines (CXCL1 to CXCL16) and their receptors (CXCR1 to CXCR6) in colorectal cancer. Overall, increased expression levels of CXC chemokines correlate with poor prognosis.     

Erlotinib in the treatment of non-small cell lung cancer

Because erlotinib, an epidermal growth factor receptor tyrosine kinase (EGFRTK) inhibitor, has been shown to be effective and well-tolerated as a second/third-line treatment in the therapy of advanced non-small cell lung cancer (NSCLC), this agent has been recently approved for human NSCLC therapy in the European Union. Although additive and synergistic effects of erlotinib and conventional chemotherapy were demonstrated in the combined regime preclinically, this has yet to be approved in the clinic. Since erlotinib and cytotoxic drugs have different biological targets, they have distinct side effects as well: erlotinib has no toxic effect on the bone marrow, but can cause diarrhea and rash, the latter being thought to be an indicator of the therapeutic efficacy. Several ongoing clinical trials are investigating the potential role of erlotinib in different settings in human NSCLC. This review intends to integrate our current knowledge on the erlotinib treatment in NSCLC.     

CXCL5 regulation of proliferation and migration in human non-small cell lung cancer cells

Epithelial neutrophil-activating peptide-78 (CXCL5), a member of the subgroup of CXC-type chemokine family, is an inflammatory factor involved in the progression of lung cancer, but the underlying mechanism remains unclear. In this study, we investigated the effects of CXCL5 on proliferation and migration in non-small cell lung cancer (NSCLC) using tissue microarrays from NSCLC patients and H460 cells transfected with a CXCL5-interfered lentivirus vector or stimulated with recombinant CXCL5. We observed that the expression of CXCL5 was significantly higher in lung cancer cell lines, and high CXCL5 was associated with high chemokine (C-X-C motif) receptor 2 expression and was significantly associated with poor differentiation. The high expression of CXCL5 was associated with poor NSCLC prognosis and was an independent predictive factor. Furthermore, downregulation of CXCL5 in H460 cells significantly reduced proliferation and migration. Recombinant CXCL5 promoted H460 cell proliferation and movement by activating MAPK/ERK1/2 and PI3K/AKT signaling. Our study elucidates the important role of CXCL5 in the progression and prognosis of NSCLC. These findings suggested that CXCL5 might be a potential biomarker and novel therapeutic target for lung cancer.     

榄香烯治疗非小细胞肺癌的作用机制研究进展

榄香烯注射液是从天然中草药姜科植物温郁金中提取获得的萜烯类化合物,其主要生物学活性为降低肿瘤细胞有丝分裂能力,诱导肿瘤细胞凋亡,抑制肿瘤细胞的生长,从而改善NSCLC患者的临床症状,增强患者免疫力.本文主要从杀灭癌细胞、诱导癌细胞凋亡、抑制癌细胞血管形成、增强患者免疫力等几方面综述榄香烯注射液对非小细胞肺癌的作用机制.     

CD10 expression in non-small cell lung cancer.

CD10 is a cell surface endopeptidase that inactivates various potentially growth stimulatory peptides. In lung cancer cell lines this downregulation has been associated with increased proliferation. Downregulation of CD10 in lung cancer tissue is described, suggesting a potential role in carcinogenesis and a possible use of CD10 as a prognostic marker. We aimed to determine the rate of CD10 expression in our non-small cell lung cancer (NSCLC) collection and to clarify its correlation with clinicopathological parameters and patient survival. 114 NSCLC were analysed immunohistochemically using a monoclonal CD10 antibody (clone NCL-CD10-270) on an NSCLC tissue micro array. The staining was semiquantitatively scored. CD10 expression was observed in 19% of cases, without any significant association with tumour type, -size, -grading, nodal status, clinical stage, and patient survival time. We conclude that a diagnostic use of CD10 immunostaining in NSCLC is unlikely.     

Concomitant hypermethylation of multiple genes in non-small cell lung cancer (NSCLC)

Primary lung cancer remains the leading cause of cancer death worldwide. Promoter hypermethylation is a major inactivation mechanism of tumor-related genes, and increasingly appears to play an important role in carcinogenesis. In the present study, we used quantitative methylation-specific PCR (Q-MSP) assays to analyze promoter hypermethylation of nine genes in a large cohort of well-characterized non-small cell lung cancer (NSCLC) and explore their associations with the clinicopathological features of tumor. We found that there were significant differences in methylation levels for six of nine gene promoters between cancerous and noncancerous lung tissues. More importantly, with 100% diagnostic specificity, high sensitivity, ranging from 44.9% to 84.1%, was found for each of the nine genes. Interestingly, promoter hypermethylation of most genes was closely associated with histologic type, which was more frequent in squamous cell carcinomas (SCC) than in adenocarcinomas (ADC). In addition, highly frequent concomitant methylation of multiple genes was found in NSCLC, particularly in SCC. Our data showed that multiple genes were aberrantly methylated in lung tumorigenesis, and that they were closely associated with certain clinicopathological features of NSCLC, particularly of the histologic type, suggesting that these hypermethylated genes could be potential biomarkers in early detection of NSCLC in high-risk individuals, as well as in evaluating the prognosis of NSCLC patients.     

Cardiac glycosides induce autophagy in human non-small cell lung cancer cells through regulation of dual signaling pathways

Na(+)/K(+)-ATPase targeted cancer therapy has attracted increasing interests of oncologists in lung cancer field. Although multiple anti-cancer mechanisms of cardiac glycosides as Na(+)/K(+)-ATPase inhibitors are revealed, the role of autophagy and related molecular signaling pathway for the class of compounds in human non-small cell lung cancer (NSCLC) cells has not been systematically examined. We herein investigated the anti-cancer effects of two representative cardiac glycosides, digoxin and ouabain, in A549 and H460 cell lines. Both agents caused significant growth inhibition at nanomolar level. The cardiac glycosides were found to induce moderate G(2)/M arrest but not apoptosis at IC(50) level in the NSCLC cell lines. Moreover, autophagy was markedly induced by both agents, as evidenced by the time- and dose-dependent increase of LC3-II, up-regulation of Atg5 and Beclin1, as well as by the observations through acridine orange staining, transmission electron microscopy and quantification of GFP-LC3 fluorescence. Importantly, AMP-activated protein kinase (AMPK) pathway was activated, resulting in mammalian target of rapamycin (mTOR) deactivation during autophagy induction. Moreover, extracellular-signal-regulated kinase 1/2 (ERK1/2) activation was simultaneously found to be involved in the autophagy regulation. Co-treatment with respective inhibitors or siRNAs could either block the autophagic phenotypes and signals, or significantly increase the cellular viability, indicating the drugs-induced autophagy plays tumor-suppressing role. This work provides first evidence showing that the cardiac glycosides induce autophagy in human NSCLC cells through regulation of both mTOR and ERK1/2 signaling pathways. The autophagy may at least partially account for the growth inhibitory effects of the compounds in human NSCLC cells.     

Bombesin activates MAP kinase in non-small cell lung cancer cells

The effects of bombesin (BB) on mitogen activated protein (MAP) kinase were investigated using non-small cell lung cancer (NSCLC) cells. By Western blot, both 42 and 44 kDalton forms of MAP kinase were present in NCI-H1299 and NCI-H838 cells. Addition of BB to NCI-H1299 cells resulted in phosphorylation of the MAP kinase substrate myelin basic protein (MBP). Phosphorylation of MBP was maximal 6 min after the addition of 10 nM BB to NCI-H1299 cells. Addition of gastrin releasing peptide (GRP) or GRP14-27 but not GRP1-16 to NCI-H 1299 cells caused MBP phosphorylation. The effects of BB were inhibited by BW2258U89, a BB receptor antagonist, and PD98059, a MAP kinase kinase inhibitor. Also, PD98059 inhibited the clonal growth of NCI-H1299 cells. These data suggest that MAP kinase may be an important regulatory enzyme in NSCLC.     

Estrogen receptor signaling pathways in human non-small cell lung cancer

Lung cancer is the most common cause of cancer mortality in male and female patients in the US. The etiology of non-small cell lung cancer (NSCLC) is not fully defined, but new data suggest that estrogens and growth factors promote tumor progression. In this work, we confirm that estrogen receptors (ER), both ERalpha and ERbeta, occur in significant proportions of archival NSCLC specimens from the clinic, with receptor expression in tumor cell nuclei and in extranuclear sites. Further, ERalpha in tumor nuclei was present in activated forms as assessed by detection of ER phosphorylation at serines-118 and -167, residues commonly modulated by growth factor receptor as well as steroid signaling. In experiments using small interfering RNA (siRNA) constructs, we find that suppressing expression of either ERalpha or ERbeta elicits a significant reduction in NSCLC cell proliferation in vitro. Estrogen signaling in NSCLC cells may also include steroid receptor coactivators (SRC), as SRC-3 and MNAR/PELP1 are both expressed in several lung cell lines, and both EGF and estradiol elicit serine phosphorylation of SRC-3 in vitro. EGFR and ER also cooperate in promoting early activation of p42/p44 MAP kinase in NSCLC cells. To assess new strategies to block NSCLC growth, we used Faslodex alone and with erlotinib, an EGFR kinase inhibitor. The drug tandem elicited enhanced blockade of the growth of NSCLC xenografts in vivo, and antitumor activity exceeded that of either agent given alone. The potential for use of antiestrogens alone and with growth factor receptor antagonists is now being pursued further in clinical trials.     

非小细胞肺癌靶向治疗的临床前研究进展

针对表皮生长因子受体（EGFR）和血管生成（angiogenesis）信号通路的靶向治疗已经在晚期非小细胞肺癌的治疗上取得成功,但由于抗药性的存在,大多数晚期患者的生存时间仍然提高有限。继发性的EGFR T790M突变和原癌基因肝细胞生长因子受体（MET）的扩增被鉴定为两种主要的抗药机制。最近转化生长因子-β（TGF-β）/白介素-6信号通路被报道能介导选择性和适应性地对erlotinib的抗药。另一方面,Kras突变所致肺癌的靶向治疗方面也取得了一些进展。双重抑制磷脂酰肌醇3-激酶（PI3K）和促分裂素原活化蛋白激酶激酶（MEK）信号通路可导致Kras突变肿瘤的显著消退,联合抑制SRC、PI3K和MEK可使丝氨酸/苏氨酸蛋白激酶11（Lkb1）缺失,Kras突变的肺癌小鼠的肿瘤明显消退,抑制核因子-κB（NF-κB）信号通路导致p53缺失,Kras突变的肿瘤发展显著减慢。这些发现都为发展非小细胞肺癌患者的靶向治疗提供了有力的支持。     

Lymphokine-activated killer cell susceptibility in epirubicin-resistant and parental human non-small cell lung cancer (NSCLC)

The aim of this study was to evaluate that: (i) epirubicin-HCl (EPI) and lymphokine-activated killer (LAK) cells cytotoxicity may be mediated by free radical generation; and (ii) resistant H1299 cells may be more sensitive to combined treatment of LAK cells plus EPI than the LAK or EPI treatment alone. Viability of H1299 cells treated with EPI, LAK and LAK plus EPI was measured using the MTT test. Amount of glutathione (GSH), protein content and enzymatic activity were measured by spectrophotometer. Glutathione S-transferase (GST)-pi expression in the cells was determined by western blot analysis. LAK plus EPI combined treatment increased susceptibility of H1299 WT and H1299 EPI(R) (300-fold EPI resistant) cells to LAK cell cytotoxicity. The resistance of H1299 EPI(R) cells to EPI appears to be associated with a developed tolerance to free radicals, most likely because of a 2-fold increase in NADPH-dependent-cytochrome-P450 reductase (NADPH-CYP reductase) activity, 11-fold GST activity and 11-and 7-fold augmented selenium dependent and independent glutathione peroxidase (GSH-Px) activity, respectively. Amount of GST-pi in H1299 EPI(R) cells is statistically different from negative control and H1299 WT (p < 0.01). It is proposed that production of reactive oxygen species and hydrogen peroxide by the treatment of EPI and LAK cells can cause cytotoxicity of H1299 WT and H1299 EPI(R) cells. Superoxide dismutase, catalase, GSH-Px, GST, NADPH-CYP reductase and GSH must be considered as part of the intracellular antioxidant defense mechanism of H1299 WT and H1299 EPI(R) cells against reactive oxygen species. Combined treatment of EPI plus LAK cells caused the increasing cytotoxicity on the H1299 EPI(R) cells.