Synergistic activities of Panobinostat and doxorubicin in soft tissue sarcomas.

BACKGROUND: Soft tissue sarcomas (STS) are rare diseases typically arising from connective tissues in children and adults. However, chemotherapies involved in the treatment of STS may cause toxic side effects and multi-drug chemoresistance, making the treatment even more challenging. Histone deacetylase inhibitors (HDACi) are epigenetic agents which have shown anti-tumor effects as single agent as well as combination use with other drugs. Our project intends to prove the same effects in STS. METHODS: Panobinostat (LBH589) plus doxorubicin was selected for investigations based on our previous research. Tumor xenografts were tried in an epithelioid sarcoma model to validate good synergy effects in vivo and a leiomyosarcoma model was used as a negative comparison group. Gene profile changes were studied afterwards. The possible pathway changes caused by HDACi were explored and validated by several assays. RESULTS: Synergy effect of LBH589 plus doxorubicin was successfully validated in STS cell lines and an epithelioid sarcoma mice model. We tried to reduce the dose of doxorubicin to a lower level and found the drug combination can still inhibit tumor size in mice. Furthermore, gene profile changes caused by LBH589 was studied by RNA-Sequencing analysis. Results showed LBH589 can exert effects on a group of target genes which can regulate potential biological functions especially in the cell cycle pathway.

Preclinical evaluation of the VEGF/Ang2 bispecific nanobody BI 836880 in nasopharyngeal carcinoma models.

Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) is endemic to parts of Asia and overexpression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α are common in NPC. Anti-vascular agents have known clinical activity in patients with recurrent/ metastatic NPC and in this study, we investigated the anti-tumor effect of BI 836880, a humanized bispecific nanobody against VEGF and angiopoietin-2 (Ang2), in preclinical models of EBV-positive and EBV-negative NPC. The efficacy of BI 836880 was also compared with bevacizumab, a recombinant humanized monoclonal antibody against VEGF. We found that BI 836880 could exert growth-inhibitory effect on endothelial cells (HUVEC-C) and the EBV-negative NPC cell line (HK1), but to a lesser extent in the EBV-positive NPC cell lines, C17C and C666-1. In patients-derived xenograft (PDX) models of NPC - Xeno-2117 and Xeno-666, BI 836880 could suppress tumor growth and Ki67, as well as induce tumor necrosis and reduce microvessel density. Moreover, treatment with BI 836880 increased the level of macrophage infiltration in both PDX tumor models of NPC, suggesting that BI 836880 may exert immunomodulatory effect on the NPC immune microenvironment. When compared with bevacizumab, BI 836880 appeared to show at least comparable activity as bevacizumab in terms of its anti-proliferative and anti-angiogenic effects. This study showed that BI 836880 has anti-proliferative, anti-angiogenic and possibly immunomodulatory effect in clinical models of NPC, therefore the dual targeting of VEGF and Ang2 signaling in NPC should be further investigated.

Targeting the polycomb repressive complex-2 related proteins with novel combinational strategies for nasopharyngeal carcinoma.

Aberrant epigenetic regulation is critically involved in the pathogenesis of nasopharyngeal carcinoma (NPC), where abnormal histone methylation can be found in polycomb repressive complex-2 (PRC2) related cancer gene loci. This study investigated some novel combinational strategies against NPC in vitro using PRC2-targeting agents as a backbone. PRC2 subunit proteins were overexpressed in over 70% of NPC tumors and enhancer of zeste homolog-2 (EZH2) expression correlated with more advanced T-stage. Basal expression of EZH2 and embryonic ectoderm development (EED) was higher in Epstein-Bar virus (EBV)+ NPC cells than EBV- cells. Treatment with an EED inhibitor (EED226) led to reduced levels of H3K27me3 with minimal inhibitory effect on NPC cell growth. The combination of an EZH2 inhibitor (EPZ-6438) and trichostatin-A (TSA) yielded the highest synergy score (12.64) in NPC cells in vitro than combinations using EED226 and agents like chemotherapy and azacitadine. Global gene expression analysis showed that EED226 predominantly affects the expression of major histocompatibility complex (MHC) class I genes and cell cycle-related genes in NPC cells. Furthermore, treatment with EED226 resulted in increased MHC-I proteins in vitro. Based on the prediction of an artificial neural network, a synergistic inhibitory effect on growth was found by combining EED226 with cyclin dependent kinase (CDK) 4/6 inhibitor (LEE011) in NPC cells. In summary, this study found that PRC2-targeting agents could exert synergistic effect on growth inhibition when combined with TSA or LEE011 in NPC cells. Since MHC-I genes alterations are found in a third of NPC tumors, the effect of EED226 on MHC-I genes expression on response to immunotherapy in NPC warrants further investigations.

Preclinical evaluation of ribociclib and its synergistic effect in combination with alpelisib in non-keratinizing nasopharyngeal carcinoma.

Ribociclib is a specific cyclin dependent kinase (Cdk) 4/6 inhibitor that induces G1 arrest by blocking the formation of cyclin D1-Cdk4/6 complex and inhibiting retinoblastoma (RB) phosphorylation. Cyclin D1 is overexpressed in over 90% of nasopharyngeal carcinoma (NPC) and CCND1 gene activation plays a critical role in NPC pathogenesis. This study evaluated the preclinical activities of ribociclib in NPC cell lines and patient derived xenograft (PDX) models. Over 95% cell growth inhibition was observed at 96 hours after ribociclib treatment. (IC50 concentrations: HK1 = 1.42 ± 0.23 µM; HK1-LMP1 = 2.18 ± 0.70 µM and C666-1 = 8.26 ± 0.92 µM). HK1 and C666-1 cells were chosen for analysis of ribociclib on kinase signaling, apoptosis and cell cycle. Treatment with ribociclib for 48 hours consistently showed a dose-dependent reduction in phosphorylated and total RB expression and G1 cycle arrest was only observed. Combining ribociclib with the alpha-specific PI3K inhibitor alpelisib showed a synergistic effect in two NPC PDX models in nude mice. The co-treatment induced a significant reduction in tumor volume in both xeno-666 and xeno-2117 compared with ribociclib treatment alone and control (p < 0.01). In summary, ribociclib is active in NPC models and the effect on growth inhibition was augmented when combined with alpelisib. This study supports the clinical evaluation of ribociclib in NPC.

Upregulation of Bcl2 in NSCLC with acquired resistance to EGFR-TKI.

Lung cancer has the highest incidence and mortality rate worldwide among all malignancy-associated mortalities, of which non-small cell lung cancer accounts for 80% of all cases. Resistance against epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) develops following 8-12 months of disease progression, and is a critical issue. HCC827 cell lines with resistance to EGFR-TKIs were successfully screened. The half maximal inhibitory concentration values were 1,000-fold higher than the values for the parental HCC827 cell line, thereby demonstrating cross-resistance against the same family of TKIs. The expression of B-cell lymphoma 2 (Bcl2) was markedly increased in the resistant clones, as well as in the patient biopsies. The phosphatase and tensin homolog phosphoinositide 3-kinase signaling axis is a potential mechanism for acquiring resistance, and therefore targeting Bcl2 may be a useful strategy for further investigations.

Efficacy, Safety, and Pharmacokinetics of Axitinib in Nasopharyngeal Carcinoma: A Preclinical and Phase II Correlative Study.

Purpose: We hypothesized that axitinib is active with an improved safety profile in nasopharyngeal carcinoma (NPC).Experimental Design: We evaluated axitinib in preclinical models of NPC and studied its efficacy in a phase II clinical trial in recurrent or metastatic NPC patients who progressed after at least one line of prior platinum-based chemotherapy. We excluded patients with local recurrence or vascular invasion. Axitinib was started at 5 mg twice daily in continuous 4-week cycles. Primary endpoint was clinical benefit rate (CBR), defined as the percentage of patients achieving complete response, partial response, or stable disease by RECIST criteria for more than 3 months.Results: We recruited 40 patients, who received a median of 3 lines of prior chemotherapy. Axitinib was administered for a mean of 5.6 cycles, with 16 patients (40%) receiving ≥6 cycles. Of 37 patients evaluable for response, CBR was 78.4% (95% CI, 65.6%-91.2%) at 3 months and 43.2% (30.4%-56.1%) at 6 months. Grade 3/4 toxicities were uncommon, including hypertension (8%), diarrhea (5%), weight loss (5%), and pain (5%). All hemorrhagic events were grade 1 (15%) or grade 2 (3%). Elevated diastolic blood pressure during the first 3 months of axitinib treatment was significantly associated with improved overall survival (HR, 0.29; 95% CI, 0.13-0.64, P = 0.0012). Patient-reported fatigue symptom was associated with hypothyroidism (P = 0.039). Axitinib PK parameters (Cmax and AUC(0-t)) were significantly correlated with tumor response, toxicity, and serum thyroid-stimulating hormone changes.Conclusions: Axitinib achieved durable disease control with a favorable safety profile in heavily pretreated NPC patients. Clin Cancer Res; 24(5); 1030-7. ©2018 AACR.

Preclinical evaluation of PI3K inhibitor BYL719 as a single agent and its synergism in combination with cisplatin or MEK inhibitor in nasopharyngeal carcinoma (NPC).

Nasopharyngeal carcinoma (NPC) is endemic to Southeast Asia and over 40% of NPC tissues harbor PIK3CA amplifications. This study aims to study the preclinical activity of a novel PI3K inhibitor, BYL719, in 6 NPC cell lines: C666-1, CNE-2, HK1, HK1-EBV, HONE-1 and HONE-1-LMP1. Over 70% of growth inhibition was attained when NPC cell lines were exposed to increasing concentrations of BYL719, with IC50 values at the low micro-molar range. Two BYL719-sensitive cell lines that harbor PIK3CA mutations, CNE-2 and HONE-1, were selected for further analysis on the effect of BYL719 on cell cycle progression, apoptosis and PI3K signaling. BYL719 significantly reduced the phosphorylation of Akt, and the Akt-mTOR axis downstream effector S6 in these 2 cell lines, but a feedback activation of MAPK was observed at 72 hours post-treatment. BYL719 induced G0/G1 cell cycle arrest and apoptosis in both cell lines. In 3D cell culture models, the growth of NPC spheroids was significantly inhibited in a dose-depending manner. When BYL719 was combined with a MEK inhibitor (AZD6244) in a 3D cell culture system, strong synergism on NPC cell growth was observed with attenuation of MAPK activation. A synergistic inhibitory effect on growth was observed when BYL719 was combined with higher dose levels of cisplatin. These data suggest that BYL719 has preclinical activity in NPC cell lines especially in those which harbor PIK3CA mutation. Combination with a MEK inhibitor maybe a useful strategy that warrants further investigation.

Preclinical evaluation of afatinib (BIBW2992) in esophageal squamous cell carcinoma (ESCC).

Esophageal squamous cell carcinoma (ESCC) is the eighth most common cancer worldwide. Epidermal growth factor receptors (EGFR) are often overexpressed in esophageal cancers, thus anti-EGFR inhibitors have been evaluated in ESCC. Afatinib was an irreversible inhibitor of these ErbB family receptors. This study characterized the preclinical activity of afatinib in five ESCC cell lines: HKESC-1, HKESC-2, KYSE510, SLMT-1 and EC-1. ESCC cell lines were sensitive to afatinib with IC50 concentrations at lower micro-molar range (at 72 hour incubation: HKESC-1 = 0.002 µM, HKESC-2 = 0.002 µM, KYSE510 = 1.090 µM, SLMT-1 = 1.161 µM and EC-1 = 0.109 µM) with a maximum growth inhibition over 95%. Afatinib can strongly induce G0/G1 cell cycle arrest in HKESC-2 and EC-1 in a dose- and time-dependent manner. The phosphorylation of ErbB family downstream effectors such as pAKT, pS6 and pMAPK were significantly inhibited in HKESC-2 and EC-1. Apoptosis was observed in both cell lines at 24 hours after exposure to afatinib, as determined by the presence of cleaved PARP. Afatinib could effectively inhibit HKESC-2 tumor growth in mice without obvious toxicity. Afatinib alone has shown excellent growth inhibitory effect on ESCC in both in vitro and in vivo models, however, no synergistic effect was observed when it was combined with chemotherapeutic agents such as 5-fluorouracil (5-FU) and cisplatin. In summary, afatinib can inhibit cell proliferation effectively by arresting the cells in G0/G1 phase, as well as inducing apoptosis in ESCC. These findings warrant further studies of afatinib as therapeutic agent in treating ESCC.

Preclinical evaluation of the mTOR-PI3K inhibitor BEZ235 in nasopharyngeal cancer models.

The dual PI3K-mTOR inhibitor BEZ235 was evaluated in preclinical models of nasopharyngeal carcinoma (NPC). The IC50 value of BEZ235 for growth was in the nanomolar range in vitro, induce G1 cycle arrest and apoptosis, and inhibited AKT and mTOR signaling in most NPC cell lines. No synergistic effect was observed when BEZ235 was combined with chemotherapy. BEZ235 increased MAPK activation in vitro but not in vivo. A daily schedule was more effective than a weekly schedule on tumor growth and inhibition of downstream mTOR signaling in vivo. The activity of BEZ235 maybe independent of the PIK3CA amplification and mutation status.

Preclinical evaluation of the PI3K-mTOR dual inhibitor PF-04691502 as a novel therapeutic drug in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is common in Southeast Asia and over 40% of NPC tissues have PIK3CA amplification. This study characterized the preclinical activity of a novel potent dual PI3K/mTOR inhibitor, PF-04691502, in five NPC cell lines: CNE-1, HK1, CNE-2, HONE-1 and C666-1, in which all of the cell lines possessed basal and activated expression of Akt and p70S6K. Over 80% inhibition of cell growth in all of these cell lines were achieved after 72 h of PF-04691502 incubation and their IC50 were in hundred nanomolar range. CNE-2, HK1 and HONE-1 were selected to further evaluate the effect of PF-04691502 on cell cycle, apoptosis and Akt downstream signaling. PF-04691502 induced G0/G1 cell cycle arrest and apoptosis at 24 h incubation and it significantly abrogated Akt and its downstream signaling by suppressing the expression of p-mTOR, p-p70S6K, p-Akt(S473, T308), p-S6 and p-4E-BP1, suggesting its effectiveness in inhibition of translation and protein synthesis. Anti-proliferation was also observed in 3D culture system and spheroids formation of NPC cell line HONE-1-EBV was strongly inhibited by PF-04691502. Antitumor activity was observed in CNE-2 xenograft in 2 weeks of 10 mg/kg PF-09641502 treatment to tumor bearing athymic nude mice. Both tumor volume and weight in treatment group were significantly lower than those in vehicle group while no obvious body weight decrease was found, suggesting this working dose was effective and well-tolerated. Additive effects were observed in combination of PF-09641502 with either cisplatin or paclitaxel. There were no synergistic effect observed in drug combination but PF-09641502 alone was effective in treating cisplatin resistant cell lines as compared to its parental control. The beneficial effects of PF-09641502 in both in vitro and in vivo studies for NPC warrant a further investigation.

Preclinical evaluation of combined TKI-258 and RAD001 in hepatocellular carcinoma.

PURPOSE: RAD001 targets at the mammalian target of rapamycin (mTOR), while TKI-258 is a potent tyrosine kinase inhibitor targeting at fibroblast growth factor receptor, vascular endothelial growth factor receptor, platelet-derived growth factor receptor and c-kit. We aim to study the activity of combined RAD001 and TKI-258 in cell lines and xenograft model of hepatocellular carcinoma (HCC), with reference to the parallel and upstream pathways of Akt-mTOR axis. METHODS: A panel of 4 human HCC cell lines HepG2, Hep3B, PLC/PRF/5 and Huh7 and the Hep3B-derived xenograft were treated with TKI-258 or/and RAD001, respectively. Related mechanistic studies (including apoptosis and angiogenesis) were conducted. RESULTS: There was an enhanced increase in suppression of cell proliferation with combined TKI-258 and RAD001 compared with either drug alone. The combination could significantly suppress the phosphorylation of mTOR, MEK1/2 and p38 MAPK. Although the addition of the TKI258 only slightly suppressed the phosphorylation of AKT induced by RAD001, the pi-mTOR and its downstream signaling pathways including pi-p70S6K, pi-S6 and pi-4EBP1 were lowered in the combination. In Hep3B-derived xenograft, TKI-258 and RAD001 had shown an enhanced inhibition of tumor growth without impact on the weight of animals. There was a reduction in microvessel density in the xenograft with the combination, which indicated an enhanced inhibition on angiogenesis. Pro-caspases-3 and PARP cleavage were slightly detected at 48 h after treatment, suggesting that the combination mainly increased the cytostatic arrest ability. CONCLUSIONS: The combination of RAD001 and TKI-258 was active in HCC via inhibition of both mTOR-mediated signaling and its parallel pathways.

Enhanced Antitumor Activity with Combining Effect of mTOR Inhibition and Microtubule Stabilization in Hepatocellular Carcinoma.

Mammalian target of rapamycin (mTOR) and the microtubules are shown to be potential targets for treating hepatocellular carcinoma (HCC). PI3K/Akt/mTOR activation is associated with resistance to microtubule inhibitors. Here, we evaluated the antitumor activity by cotargeting of the mTOR (using allosteric mTOR inhibitor everolimus) and the microtubules (using novel microtubule-stabilizing agent patupilone) in HCC models. In vitro studies showed that either targeting mTOR signaling with everolimus or targeting microtubules with patupilone was able to suppress HCC cell growth in a dose-dependent manner. Cotargeting of the mTOR (by everolimus) and the microtubules (by patupilone, at low nM) resulted in enhanced growth inhibition in HCC cells (achieving maximal growth inhibition of 60-87%), demonstrating potent antitumor activity of this combination. In vivo studies showed that everolimus treatment alone for two weeks was able to inhibit the growth of Hep3B xenografts. Strikingly, the everolimus/patupilone combination induced a more significant antitumor activity. Mechanistic study demonstrated that this enhanced antitumor effect was accompanied by marked cell apoptosis induction and antiangiogenic activity, which were more significant than single-agent treatments. Our findings demonstrated that the everolimus/patupilone combination, which had potent antitumor activity, was a potential therapeutic strategy for HCC.

Preclinical evaluation of the AKT inhibitor MK-2206 in nasopharyngeal carcinoma cell lines.

Nasopharyngeal carcinoma (NPC) is endemic to Asia and over 40 % of NPC tissues harbor PIK3CA amplifications. This study characterized the preclinical activity of MK-2206, an oral allosteric inhibitor of AKT in 6 NPC cell lines: C666-1, HK1, HONE-1-EBV, HONE-1, CNE-2 and HNE-1. Exposure to increasing concentrations of MK-2206 resulted in over 95 % of growth inhibition in all NPC cell lines with IC50 values in the low micromolar range. Further experiments were performed in 3 representative NPC cell lines: CNE-2 (harbor PIK3CA mutation and most sensitive to MK-2206), C666-1 (carries PIK3CA amplification), and HONE-1-EBV (least sensitive to MK-2206). MK-2206 induced G0/G1 cycle arrest in all 3 cell lines, but could induce apoptosis only in CNE-2 cells. MK-2206 significantly abrogated AKT signaling in all 3 cell lines by inhibiting the activation of AKT and its downstream effectors (FKHR, GSK3ß and BAD). MK-2206 also reduced mTOR signaling by reducing activation of mTOR and its downstream 4E-BP1 and p70S6 kinase. MAPK activation was observed in HONE-1 and C666-1 cells, but not in CNE-2 cells following exposure to MK-2206. The addition of MK-2206 to cisplatin (but not with paclitaxel) has a supra-additive inhibitory effect on growth in vitro. In summary, MK-2206 can inhibit growth and abrogate AKT and mTOR signaling in NPC cell lines. This agent is currently being evaluated in a phase II study in metastatic NPC.

Lung ischaemia-reperfusion induced gene expression.

OBJECTIVES: Pulmonary dysfunction following lung ischaemia-reperfusion is a well-known phenomenon, which may contribute to post-cardiac surgical morbidity. The process is associated with pulmonary inflammatory response and cellular apoptosis. Early molecular mechanisms leading to such lung injury remain largely unknown. We examined whether lung ischaemia and reperfusion cause significant expression changes in numerous genes in the lungs involved in pulmonary apoptosis and other cellular processes by using oligonucleotide microarrays in an experimental model of rodent lung ischaemia-reperfusion injury. METHODS: Sprague-Dawley rodents (n=5 in each group) were anaesthetised and underwent controlled ventilation, with varying durations of warm lung ischaemia (60 and 90 min) followed by a short reperfusion period. The right middle lobe of the lung was harvested. Gene expression changes in the lungs were analysed by rodent DNA microarray chips, and reverse transcription polymerase chain reaction (RT-PCR) performed to validate changes in gene expression. RESULTS: Significant expression changes, with reference to false discovery rate (FDR) controls, were detected in over 80 genes following controlled lung ventilation, and more than 50 were up-regulated more than 2-fold. Lung ischaemia-reperfusion caused expression changes in over 50 additional genes, including many novel genes not previously associated with lung ischaemia-reperfusion. Up-regulated genes identified include those associated with apoptosis, inflammation and cell-cycle control. CONCLUSIONS: Large numbers of genes relating to cell metabolism, transcription control, inflammation and apoptosis were significantly up- and down-regulated following controlled ventilation and early lung ischaemia-reperfusion, consistent with previous studies. In addition, novel genes related to lung injury were identified. These genetic signatures provide new insights into early molecular mechanisms of ischaemia-reperfusion lung injury and help refine therapeutic strategies to lessen pulmonary dysfunction following cardiac surgery.

Ventilation during cardiopulmonary bypass: impact on neutrophil activation and pulmonary sequestration.

BACKGROUND: Cardiopulmonary bypass (CPB) is associated with neutrophil activation, pulmonary sequestration, and release of inflammatory mediators leading to pulmonary dysfunction. We investigate the effect of continuous ventilation during cardiopulmonary bypass on neutrophil activation and pulmonary sequestration. METHODS: Forty-six patients undergoing coronary artery bypass grafting with cardiopulmonary bypass were prospectively randomized to continuous ventilation and nonventilation groups. Blood samples were collected, and bronchoalveolar lavage (BAL) was performed following induction of anesthesia and at 4 hr after aortic declamping. Differential white cell count was measured, and flow cytometry to determine cell count numbers and quantify CD45 and CD11b leukocyte cell surface adhesion molecule expression was performed on the blood and BAL samples. RESULTS: Twenty-three patients were randomized to standard nonventilated CPB and 23 patients to ventilation throughout CPB. Significant increases in blood and BAL neutrophil numbers were detected at 4 hr following aortic declamping in both groups (Blood: NV p < .0001, V p < .0001; BAL: NV p = .017, V p = .0007). No significant inter-group differences in BAL and blood neutrophil numbers were found. Significantly higher blood neutrophil CD11b mean fluorescent intensity levels were present 4 hr following declamping compared with baseline in both groups (NV Blood, p = .021; V Blood p < .0001). No significant inter- or intragroup differences in BAL neutrophil CD11b mean fluorescent intensity levels were found. There was no death or major complication. CONCLUSIONS: Cardiopulmonary bypass during coronary artery bypass grafting is associated with increased neutrophil pulmonary sequestration, and blood neutrophil CD11b activation. Continuous ventilation during cardiopulmonary bypass does not significantly reduce neutrophil pulmonary sequestration or activation.

Video-assisted thoracic surgery lobectomy for lung cancer is associated with less immunochemokine disturbances than thoracotomy.

OBJECTIVE: Major surgery is immunosuppressive and could have an impact on postoperative tumor immunosurveillance and recurrence in cancer patients. Low circulating levels of insulin growth factor binding protein (IGFBP)-3 have been linked to advance prostate and the development of colonic cancers. This prospective study examined the early postoperative circulating levels of IGFBP-3, matrix metalloproteinase (MMP)-9, and tissue inhibitor of metalloproteinase (TIMP)-1 in early stage non-small cell lung cancer (NSCLC) patients undergoing major lung resection by VATS versus thoracotomy. METHODS: Forty-two consecutive patients with resectable primary NSCLC were assigned to VATS or thoracotomy approach over a 7-month-period. Blood samples were collected preoperatively and postoperatively on days (POD) 1 and 3 for enzyme linked immunosorbent assay determination of IGFBP-3, MMP-9 and TIMP-1 levels in the serum. RESULTS: There were no demographic differences between the two groups. VATS lung resection was associated with lower levels of MMP-9 and TIMP-1 on POD1 (median 628 vs 1311ng/ml, p=0.009; and 131 vs 211ng/ml, p=0.004, respectively) but higher levels of IGFBP-3 on POD3 (1366 vs 1144ng/ml, p=0.02), when compared with the thoracotomy approach. There was no perioperative mortality. CONCLUSIONS: VATS major lung resection for NSCLC is associated with higher circulating levels of IGFBP-3, and lower levels of MMP-9 and TIMP-1, compared to the thoracotomy approach. The clinical relevance of these postoperative changes on tumor biology following lung resection for cancer warrants further investigation.

Video-assisted thoracic surgery for early stage lung cancer - can short-term immunological advantages improve long-term survival?

The development of video-assisted thoracic surgery (VATS) in the past decade has changed the way many pulmonary conditions are being treated. VATS has gained popularity among clinicians due to faster recovery following surgery, less postoperative pain and better cosmesis. It is well known that surgical trauma can induce a systemic inflammatory response and affect postoperative systemic immunity. Minimal access VATS has been shown to be associated with a reduced postoperative systemic inflammatory response. Recent evidence suggests VATS is also associated with better cellular immunity, and produces less immunochemokine disturbance following surgery, when compared with the thoracotomy approach. Circulating natural killer (NK) cell numbers and levels of insulin growth factor binding protein (IGFBP) are found to be higher, and plasma levels of matrix metalloproteinases are lower following VATS than that after thoracotomy. Maintenance of immune function with VATS may have important clinical implications in lung cancer surgery.

Revisiting ischemia and reperfusion injury as a possible cause of necrotizing enterocolitis: Role of nitric oxide and superoxide dismutase.

BACKGROUND/PURPOSE: The pathogenesis of necrotizing enterocolitis (NEC) is unknown. Ischemia and reperfusion (I/R) injury has been considered a major contributing factor. Nitric oxide (NO) and superoxide dismutases (SODs) have been shown to protect bowel from I/R injury. This study aims to assess (1) the ability of premature intestine to resist I/R injury compared with mature intestine and (2) the possible role of NO and SODs in modulating such response. METHODS: Intestines from 5 groups of rats (n = 6 for each study group) were studied: (1) premature, gestational age 20 days; (2) premature, gestational age 22 days; (3) full-term, newborn; (4) infant, day 15; (5) infant, day 30. EXPERIMENTS: (1) The degrees of I/R injury after 0, 30, 60, 90 and 120 minutes, respectively, of ischemia and 25 minutes of I/R were assessed histologically by a pathologist who was unaware of the operative details. (2) Tissue NO and copper levels were measured by electroparamagnetic resonance (EPR) study; and nitric oxide synthases, copper zinc (CuZn) SODs and manganese (Mn) SODs were examined immunohistochemically. (3) and (4) I/R injury was assessed in rats that had received intraperitoneal injections of L-arginine (NO donor) and L-NAME (NO antagonist), respectively. RESULTS: For premature (1,2), newborn (3) and mature (4,5) intestines, grades of injury at maximum I/R period studied (120 minutes of ischemia, 25 minutes of reperfusion) were 0, 0, and 3, respectively (P <.05); NO levels were 1 u +/- 1.5, 3 +/- 2.5, and 22 u +/- 3.5, respectively (P <.05); Cu levels were 150 u +/- 15, 200 u +/- 41 and 12 u +/- 2, respectively (P <.05); NOS in intestines were +, +, +++ and CuZnSODs were ++, +++, +, respectively; and MnSODs were +++, ++, -, respectively. No change in NO levels was detected in groups (1), (2), or (3) after L-arginine and L-NAME injections. CONCLUSIONS: Premature rat intestine is highly resistant to I/R injury, which may indicate that I/R alone, in the absence of other predisposing factors (eg, bacterial colonization) may not be sufficient in causing NEC. Nitric oxide does not have a protective role for immature and newborn intestines in I/R as in mature intestine. The high level of SODs of the immature and newborn intestine may play an important role in its high resistance to I/R injury.