Introduction

MYOCD and SMAD3/SMAD4 form a positive feedback loop and drive TGF-β-induced epithelial-mesenchymal transition in non-small cell lung cancer

Myocardin (MYOCD) promotes Smad3-mediated transforming growth factor-β (TGF-β) signaling in mouse fibroblast cells. Our previous studies show that TGF-β/SMADs signaling activation enhances epithelial-mesenchymal transition (EMT) in human non-small cell lung cancer (NSCLC) cells. However, whether and how MYOCD contributes to TGF-β-induced EMT of NSCLC cells are poorly elucidated. Here, we found that TGF-β-induced EMT was accompanied by increased MYOCD expression. Interestingly, MYOCD overexpression augmented EMT and invasion of NSCLC cells induced by TGF-β, whereas knockdown of MYOCD expression attenuated these effects. Overexpression and knockdown of MYOCD resulted in the upregulation and downregulation of TGF-β-induced Snail mRNA, respectively. Moreover, MYOCD overexpression promoted TGF-β-stimulated NSCLC cell metastasis in vivo. MYOCD was highly expressed and positively correlated with Snail in metastatic NSCLC tissues. Mechanistically, MYOCD directly interacted with SMAD3 and sustained the formation of TGF-β-induced nuclear SMAD3/SMAD4 complex, facilitating TGF-β/SMAD3-induced transactivation of Snail. Importantly, MYOCD was transcriptionally activated by TGF-β-induced SMAD3/SMAD4 complex and CRISPR/Cas9-mediated silencing of SMAD3/SMAD4 led to a reduction in MYOCD mRNA expression. Taken together, our findings indicate that MYOCD promotes TGF-β-induced EMT and metastasis of NSCLC and identify a positive feedback loop between MYOCD and SMAD3/SMAD4 driving TGF-β-induced EMT.

Estrogen promotes tumor metastasis via estrogen receptor beta-mediated regulation of matrix-metalloproteinase-2 in non-small cell lung cancer

In non–small cell lung cancer (NSCLC), estrogen significantly promotes NSCLC cell growth via estrogen receptor beta (ERβ). However, the effects by which ERβ contributes to metastasis in NSCLC have not been previously reported. This study aims at defining whether the stimulation of ERβ promotes NSCLC metastasis in vitro and in vivo. Here, Our results showed that estrogen and ERβ agonist enhanced aggressiveness of two lung cancer cell lines (A549 and H1793) and promoted murine lung metastasis formation. ER-inhibitor Fulvestrant treatment or ERβ-knockdown significantly suppressed the migration, invasion and nodule formation of NSCLC cells. The expression level of ERβ protein was analyzed in matched samples of metastatic lymph node and primary tumor tissues from the same individuals, and we found significantly higher levels of ERβ were expressed in lymph node compared to primary tumor tissues. Moreover, Studies on both surgical biopsies and on lung cancer cells revealed that the expression level of ERβ and matrix-metalloproteinase-2 (MMP-2) were associated. Furthermore, inhibition of ERβ resulted in down-regulation of MMP-2 expression. Taken together, our results demonstrate that activation of ERβ in lung cancer cells promotes tumor metastasis through increasing expression of invasiveness-associated MMP-2. These results also highlight the therapeutic potential of inhibition of ERβin the treatment of advanced NSCLC.

Transcription factor 3 controls cell proliferation and migration in glioblastoma multiforme cell lines

Transcription factor 3 (TCF3) is a member of the T-cell factor/lymphoid enhancer factor (TCF/LEF) transcription factor family. Recent studies have demonstrated its potential carcinogenic properties. Here we show that TCF3 was upregulated in glioma tissues compared with normal brain tissues. This upregulation of the TCF3 gene probably has functional significance in brain-tumor progression. Our studies on glioblastoma multiforme (GBM) cell lines show that knock-down of TCF3 induced apoptosis and inhibited cell migration. Further analysis revealed that down-regulation of TCF3 gene expression inhibits Akt and Erk1/2 activation, suggesting that the carcinogenic properties of TCF3 in GBM are partially mediated by the phosphatidylinositol 3-kinase-Akt and MAPK-Erk signaling pathways. Considered together, the results of this study demonstrate that high levels of TCF3 in gliomas potentially promote glioma development through the Akt and Erk pathways.

S P, Wei WC, Lin HT, Yin SY, Yang NS. Rapamycin Promotes Mouse 4T1 Tumor Metastasis that Can Be Reversed by a Dendritic Cell-Based Vaccine

Suppression of tumor metastasis is a key strategy for successful cancer interventions. Previous studies indicated that rapamycin (sirolimus) may promote tumor regression activity or enhance immune response against tumor targets. However, rapamycin also exhibits immunosuppressant effects and is hence used clinically as an organ transplantation drug. We hypothesized that the immunosuppressive activities of rapamycin might also negatively mediate host immunity, resulting in promotion of tumor metastasis. In this study, the effects of rapamycin and phytochemical shikonin were investigated in vitro and in vivo in a 4T1 mouse mammary tumor model through quantitative assessment of immunogenic cell death (ICD), autophagy, tumor growth and metastasis. Tumor-bearing mice were immunized with test vaccines to monitor their effect on tumor metastasis. We found that intraperitoneal (ip) administration of rapamycin after a tumor-resection surgery drastically increased the metastatic activity of 4T1 tumors. Possible correlation of this finding to human cancers was suggested by epidemiological analysis of data from Taiwan’s National Health Insurance Research Database (NHIRD). Since our previous studies showed that modified tumor cell lysate (TCL)-pulsed, dendritic cell (DC)-based cancer vaccines can effectively suppress metastasis in mouse tumor models, we assessed whether such vaccines may help offset this rapamycin-promoted metastasis. We observed that shikonin efficiently induced ICD of 4T1 cells in culture, and DC vaccines pulsed with shikonin-treated TCL (SK-TCL-DC) significantly suppressed rapamycin-enhanced metastasis and Treg cell expansion in test mice. In conclusion, rapamycin treatment in mice (and perhaps in humans) promotes metastasis and the effect may be offset by treatment with a DC-based cancer vaccine.

Treatment patterns and outcomes in patients with non-squamous advanced non-small cell lung cancer receiving second-line treatment in a community-based oncology network

OBJECTIVES

This retrospective study used the US Oncology iKnowMed(TM) database, billing claims, and chart reviews to report treatment patterns and outcomes in late-stage non-small cell lung cancer (NSCLC) in US community oncology practices.

MATERIALS AND METHODS

Eligibility criteria included non-squamous NSCLC, stage IIIB/IV at diagnosis, ECOG performance status (PS) <3, and initiation of 2nd-line therapy (defined as index date) between 1/1/2007 and 6/30/2011 with ≥ 1 year follow-up. Key outcomes were overall survival (OS), progression-free survival(PFS), time-to-progression (TTP), and time-to-hospitalization (post-index date). Kaplan–Meier and Cox proportional hazard models were used to characterize the distribution and predictors of outcomes.

RESULTS

1168 patients were eligible for the study. The most frequent 2nd-line therapies were pemetrexed(54.4%), erlotinib-containing regimens (17.6%), and docetaxel (10.0%). Median OS and PFS were 7.5 (95%confidence interval [CI]: 6.6–8.4) and 4.1 (95% CI: 3.7–4.5) months, respectively; 57% of patients were hospitalized post-index date. EGFR testing rates were 2.3% before 2010, 15.2% in 2010, and 32.0% in 2011 (P < .001). Of EGFR-positive patients, 50.0% received erlotinib-containing regimens compared with 16.9% of EGFR-negative patients (P = 0.001). An increased risk of shorter time-to-hospitalization, after controlling for other covariates, was associated with PS = 1 (hazard ratio [HR] = 1.51; P < .001) or PS = 2(HR = 1.68; P = .001) compared with PS = 0, pre-existing comorbid fatigue (HR = 1.64; P = .003) compared with no comorbid fatigue, and progression (HR = 1.92; P < .001), when it occurred, compared with no progression. Compared with other 2nd-line treatment, erlotinib-containing regimens prolonged adjusted TTP (HR = 0.69; P = .015).

CONCLUSIONS

This retrospective observational study provides new insights into treatment patterns,biomarker testing, and outcomes in advanced NSCLC within the context of a large community oncology network. Outcomes of these community practice patients, although poor, were similar to those reported in 2nd-line clinical trials for relevant regimens. EGFR testing in community practice rose rapidly after 2010.

The eligibility of advanced non-small-cell lung cancer patients for targeted therapy clinical trials

BACKGROUND

The selection criteria for phase III trials are often stringent. We aimed to determine how many advanced non-small-cell lung cancer (NSCLC) patients would have been eligible for phase III targeted therapy trials and the proportion receiving anticancer treatment.

PATIENTS AND METHODS

From March 2007 to May 2008, all advanced NSCLC patients presented at our lung cancer multidisciplinary team meeting were included to assess eligibility for the targeted therapy trials: ECOG-4599, AVAiL, FLEX, TALENT, INTACT-1, INTACT-2, ESCAPE, NEXUS and MONET1. Medical records were examined to determine treatment utilisation and overall survival.

RESULTS

A total of 62 patients were registered: 63% male; median age 71 years; 61% stage IIIB disease. Percentages that met criteria were: ECOG-4599 31%, AVAiL 24%, FLEX 69%, TALENT 27%, INTACT-1 50%, INTACT-2 42%, ESCAPE 39%, NEXUS 63% and MONET1 34%. Common reasons for ineligibility were insufficient life expectancy, poor performance status, abnormal bloods, proteinuria and associated cancer problems. Systemic therapies were received by 66% of patients and median survival was 10.3 months.

CONCLUSION

Only 24%-69% were eligible for targeted therapy trials but 66% received anticancer treatment. Clinical trials in patients with advanced NSCLC need to be more representative of the majority of patients.

Peptides derived from human insulin-like growth factor-II mRNA binding protein 3 can induce human leukocyte antigen-A2-restricted cytotoxic T lymphocytes reactive to cancer cells

Insulin-like growth factor-II mRNA binding protein 3 (IMP-3) is an oncofetal protein expressed in various malignancies including lung cancer. This study aimed to identify immunogenic peptides derived from IMP-3 that can induce tumor-reactive and human leukocyte antigen (HLA)-A2 (A*02:01)-restricted cytotoxic T lymphocytes (CTL) for lung cancer immunotherapy. Forty human IMP-3-derived peptides predicted to bind to HLA-A2 were analyzed to determine their capacity to induce HLA-A2-restricted T cells in HLA-A2.1 (HHD) transgenic mice (Tgm). We found that three IMP-3 peptides primed HLA-A2-restricted CTL in the HLA-A2.1 Tgm. Among them, human CTL lines reactive to IMP-3 (515) NLSSAEVVV(523) were reproducibly established from HLA-A2-positive healthy donors and lung cancer patients. On the other hand, IMP-3 (199) RLLVPTQFV(207) reproducibly induced IMP-3-specific and HLA-A2-restricted CTL from healthy donors, but did not sensitize CTL in the HLA-A2.1 Tgm. Importantly, these two IMP-3 peptide-specific CTL generated from healthy donors and cancer patients effectively killed the cancer cells naturally expressing both IMP-3 and HLA-A2. Cytotoxicity was significantly inhibited by anti-HLA class I and anti-HLA-A2 monoclonal antibodies, but not by the anti-HLA-class II monoclonal antibody. In addition, natural processing of these two epitopes derived from the IMP-3 protein was confirmed by specific killing of HLA-A2-positive IMP-3-transfectants but not the parental IMP-negative cell line by peptide-induced CTL. This suggests that these two IMP-3-derived peptides represent highly immunogenic CTL epitopes that may be attractive targets for lung cancer immunotherapy.

The radiosensitization effects of Endostar on human lung squamous cancer cells H-520

Background

The present study mainly aimed to investigate the direct effects of Endostar (ES) on the proliferation and radiosensitivity of human lung squamous cancer cell line H-520.

Results

ES significantly inhibited H-520 cell proliferation in a time- and dose-dependent manner. According to the colony-forming assays, ES could increase the H-520 cell radiosensitivity. ES induced cell apoptosis, the apoptosis rate increased with the raise of ES concentration. Irradiation induced significantly higher apoptosis rate in ES-treated H-520 cells than non-treated H-520 cells. ES induced cell cycle distribution and G₀/G₁ arrest in H-520 cells, whereas irradiation induced G₂/M arrest. The phospho-p38-MAPK and p-Akt protein levels were decreased in H-520 cells after ES treatment. Furthermore, activated caspase protein level increased and Bcl-2 protein levels decreased after treatment with ES and irradiation.

Conclusion

ES significantly enhanced the sensitivity of H-520 cells to irradiation by inhibition of cellular proliferation, promotion of cell apoptosis and redistribution of cell cycle, possibly via deactivation of Akt pathway. The present study supports the possibility to use the combination of ES and ionizing irradiation to treat patients with lung squamous cell cancer in clinics.

Interstitial lung disease associated to erlotinib treatment: a case report

Introduction

Few cases of pulmonary toxicity related to epidermal growth factor receptor-targeted agents have been described.

Case presentation

We report a case of a 63-year-old white male with stage IV non-small cell lung cancer treated with erlotinib who developed a interstitial lung disease.

Conclusion

Respiratory symptoms during treatment with erlotinib should alert clinicians to rule out pulmonary toxicity. Early erlotinib withdrawal and corticoid administration were successful.

Development of the monoclonal antibody figitumumab, targeting the insulin-like growth factor-1 receptor, for the treatment of patients with non-small-cell lung cancer

Figitumumab (CP-751,871) is a fully human immunoglobulin G2 monoclonal antibody highly potent and specific against the insulin-like growth factor-1 receptor. Figitumumab has an effective half-life of approximately 20 days, and it has been well tolerated in clinical studies when given alone or in combination with chemotherapy and targeted agents. Mild to moderate asymptomatic hyperglycemia is observed with figitumumab therapy, but it is generally manageable and well tolerated. Because of its extended half-life and absence of dose-limiting toxicity and hypersensitivity, figitumumab compares well to other compounds in its class. Furthermore, recent data suggest that figitumumab might be active in combination with platinum doublets for the treatment of chemotherapy-naive non-small-cell lung cancer (NSCLC). This article discusses the results to date of the figitumumab development program and the rationale for further testing of this agent as a therapeutic option for the treatment of patients with NSCLC.

Cancer treatments: can we find treasures at the bottom of the sea?

Because of the poor results observed after platinum-based first-line chemotherapy, research on new strategies for second-line treatment of advanced non-small-cell lung cancer (NSCLC) is warranted. Current research focuses on the development of new agents and the assessment of a combination of therapies, especially those with different mechanisms of action. PM02734 (elisidepsin, Irvalec) is a compound related to Kahalalide F (KF), a moderately soluble marine product that belongs to a family of dehydro aminobutyric acid-containing peptides isolated from the herbivorous marine mollusk Elysia rufescens. Preclinical and clinical studies showed that KF induces strong cytotoxic activity against different solid tumors, including NSCLC, particularly in patients with squamous histology; in fact, almost 40% of patients treated in the second line were still alive at 1 year after beginning treatment with KF. Analysis of data collected during clinical development has revealed that KF has a predictable and manageable toxicity profile. The toxicities most commonly associated with KF are generally transient and mild or moderate. The absence of hematologic toxicity and cumulative toxic effects suggests that KF may be suitable for combination trials with other anticancer agents. The development of KF could stopped because of the unavailability of a natural source of the compound. PM02734 is a closely related derivative of KF with similar activity and characteristics. Herein, we summarize the studies of PM02734 and future clinical perspectives.