Silencing of HIF-1alpha suppresses tumorigenicity of renal cell carcinoma through induction of apoptosis

Hypoxia-inducible factor-1alpha (HIF-1alpha) is a main responder to intracellular hypoxia and is overexpressed in many human cancers, including renal cell carcinoma (RCC). To better understanding of the role of HIF-1alpha in the tumorigenicity of RCC, we used short-hairpin RNA (shRNA) interference to inhibit HIF-1alpha expression in the human renal cancer cell line, Caki-1 and OS-RC-2. Silencing of HIF-1alpha significantly reduced the expression of HIF-1alpha in both of renal cancer cell lines. In vitro downregulation of HIF-1alpha inhibited Caki-1 and OS-RC-2 cell growth, migration and invasion. The results further showed that HIF-1alpha silencing resulted in caspase-dependent apoptosis of Caki-1 and OS-RC-2 through regulation of PI3K/Akt pathway and Bcl-2-related proteins expression. In vivo animal studies showed that tumor growth was significantly inhibited in HIF-1alpha shRNA-transfected RCC. Intratumor gene therapy with polyethylenimine-loaded HIF-1alpha shRNA also resulted in tumor growth suppression. Thus, this study demonstrates that downregulation of HIF-1alpha could suppress tumorigenicity of RCC through induction of apoptosis, and HIF-1alpha shRNA may be a promising strategy for the treatment of RCC.

COPD in Chinese nonsmokers

Little is known about chronic obstructive pulmonary disease (COPD) in Chinese nonsmokers. The present study aimed to investigate the profiles of COPD among nonsmokers based on the Chinese Epidemiological Survey of COPD (CESCOPD). In the CESCOPD, 20,245 subjects aged 40 yrs or older were interviewed with questionnaires and spirometry tests. Subjects with a post-bronchodilator forced expiratory volume in one second (FEV(1))/forced vital capacity (FVC) ratio of <0.70 were identified as having COPD. Data of 12,471 nonsmokers and 1,024 smoking COPD patients were analysed in the current study. The overall prevalence of COPD among nonsmokers was 5.2% (95% confidence interval 4.8-5.6). Being male, of advanced age, lower body mass index (BMI) and lower educational level, having exposure to environmental tobacco smoke, coal and/or biomass smoke, poor ventilation in the kitchen, a family history of respiratory disease and recurrent childhood cough were all independently associated with a higher risk of having COPD among nonsmokers. Nonsmokers with respiratory symptoms without airflow limitation showed a somewhat different pattern of risk factors. Nonsmokers with COPD were less likely to present with chronic productive coughs and lower BMI, while more likely to have received a physician diagnosis of asthma and respiratory diseases in childhood, than smokers with COPD. Chronic obstructive pulmonary disease is prevalent among Chinese nonsmokers, and nonsmoking chronic obstructive pulmonary disease may have different profiles from smoking chronic obstructive pulmonary disease.

Suppression of protein phosphatase 2 differentially modulates VEGF- and FGF2-induced signaling in ovine fetoplacental artery endothelial cells

Vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF2) elicit cellular responses via activation of protein kinases and phosphatases. We have reported that the MEK1/2/ERK1/2 and PI3K/AKT1 pathways are critical for VEGF- and FGF2-stimulated ovine fetoplacental artery endothelial (OFPAE) cell proliferation. We have also shown that protein phosphatase 3 (PPP3) differentially modulates VEGF- and FGF2-stimulated cell proliferation and activation of ERK1/2 and AKT1 in OFPAE cells. Herein, we investigated if protein phosphatase 2 (PPP2) modulated VEGF- and FGF2-induced ERK1/2, AKT1, and p38 MAPK activation and VEGF- and FGF2-stimulated cell proliferation in OFPAE cells. Small interfering RNA (siRNA) specifically targeting human PPP2CA catalytic subunit alpha (PPP2CA) was used to suppress PPP2CA expression in OFPAE cells. When compared with scrambled siRNA, PPP2CA siRNA decreased (p<0.05) PPP2CA protein levels (approximately 70%) and activity (approximately 50%) without altering protein levels of PPP3 catalytic subunit alpha (PPP3CA), nitric oxide synthase 3 (NOS3), ERK1/2, AKT1, and p38 MAPK. FGF2, but not VEGF rapidly (< or =5 min) induced p38 MAPK phosphorylation. Suppression of PPP2CA enhanced (p<0.05) VEGF-induced AKT1, but not ERK1/2 phosphorylation, whereas inhibited (p<0.05) FGF2-induced ERK1/2 and p38 MAPK and slightly attenuated FGF2-induced AKT1 phosphorylation. Suppression of PPP2CA did not significantly affect VEGF- and FGF2-stimulated OFPAE cell proliferation. Thus, suppression of PPP2CA alone differentially modulated VEGF- and FGF2-induced ERK1/2, AKT1, and p38 MAPK activation, without altering VEGF- and FGF2-stimulated cell proliferation in OFPAE cells. These data also suggest that signaling molecules other than ERK1/2, AKT1, and p38 MAPK are important mediators for VEGF- and FGF2-stimulated OFPAE cell proliferation after PPP2CA suppression.

A successful maintenance approach in inflammatory acne with adapalene gel 0.1% after an initial treatment in combination with clindamycin topical solution 1% or after monotherapy with clindamycin topical solution 1%

BACKGROUND

METHODS

A total of 300 acne subjects entered this multicentre, randomized, investigator-blinded study comparing the efficacy and safety of adapalene gel 0.1% plus clindamycin topical solution 1% versus clindamycin topical solution 1% alone. In the second part of the study (weeks 12-24), completed by 241 subjects, the efficacy and safety of adapalene gel 0.1% alone as a maintenance therapy was investigated.

RESULTS

A statistically significant greater reduction was observed from week 4 until week 12 in total lesion counts and from week 8 on for inflammatory and non-inflammatory lesion counts during the initial treatment for combination therapy compared with monotherapy. Results at week 24 for the reduction in all lesion counts during the maintenance phase were statistically significant in favour of adapalene (41.6%) compared with an increase for all lesion counts in the control group (92.1%). Adapalene alone or in combination with clindamycin topical solution was well tolerated. Few adverse events occurred, all of them during the initial treatment phase. Most of these local events were mild or moderate.

CONCLUSION

The present study confirmed the importance of a maintenance therapy after a successful initial treatment and underlined the benefit of a combination therapy with a topical retinoid such as adapalene and a topical antibiotic in the treatment of inflammatory acne.

Incidence, annualized cost, and utilization burden in patients with metastatic renal cell carcinoma

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Background: Data on burden of metastatic renal cell carcinoma (MRCC) is scarce. The objectives of this study are to examine the incidence of MRCC and the cost and utilization burden of MRCC over time. Methods: Administrative claims data from a large, US managed care plan were used to identify commercially insured and Medicare enrollees with newly diagnosed MRCC during 01/01/03–12/31/07 and continuous enrollment 12 months prior to and at least 90 days after MRCC diagnosis. Mean (median) costs and utilization during the follow-up period were annualized. Costs were 2007 CPI-adjusted. Results: 1,427 patients were identified with newly diagnosed MRCC (average age: 62.4 years 62.6% male). The annual incidence of MRCC in the managed care plan population was 3.4, 3.8, 2.9, 3.3, and 4.4 per 100,000 enrollees in 2003 through 2007, respectively. The mean (median) annual number of ambulatory visits per patient increased among patients diagnosed in 2003 to those diagnosed in 2007, from 44.9 (33.2) to 63.7 (54.8). Mean (median) annual medical costs per patient increased by year of diagnosis from $70,797 ($33,031) in 2003 to $92,521 ($48,117) in 2007. Pharmacy costs (excluding costs for medications delivered in medical settings) increased from $5,651 ($2,004) to $13,290 ($3,609), and were approximately 7.4%-14.3% of total costs during the time period. Conclusions: This study showed an apparent slight increase in MRCC incidence rates and revealed that treatment costs and health care utilization per patient increased substantially from 2003–2007 among members of this US managed care plan. The increases in health care utilization and cost suggest the evolution in treatment options over time as more therapies become available.

No significant financial relationships to disclose.

Therapeutic care in metastatic renal cell carcinoma during the follow-up phase of the RECORD-1 phase III trial

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Background: Following drug discontinuation for progression or adverse event in a clinical trial for relapsed or stage IV kidney cancer, supportive care including surgery, palliative radiotherapy, or bisphosphonates continue to be recommended by National Comprehensive Cancer Network (NCCN). However, published data on active therapeutic agents given to patients following study drug discontinuation in recent clinical trials is limited. Methods: World Health Organization Anatomical Therapeutic Chemical codes or therapeutic names, captured from the follow-up phase in a phase III clinical trial (RECORD-1) of patients with metastatic renal cell carcinoma (mRCC) patients, were used to describe antineoplastic therapies following discontinuation of study drug. Prior to trial, patients had progressed on at least one VEGFr-TKI therapy. Results: Of the 130 patients with follow-up after discontinuation of study drug, 78.5% received at least one of the following: corticosteroids, radiotherapy, protein kinase inhibitors, mTOR inhibitor, pyrimidine analogues, monoclonal antibodies, interferons, and investigational drugs. Among patients who received an active agent, nearly three-quarters (73.5%) utilized targeted therapy (protein kinase inhibitors, mTOR inhibitor, monoclonal antibodies). Conclusions: In a clinical trial setting with mRCC patients who have received several classes of systemic therapy, care delivered following study drug discontinuation often includes an active antineoplastic agent, despite the limited supportive evidence in this setting. While the placebo control with supportive care in a double-blind phase is acceptable to evaluate the efficacy and safety of a therapy for regulatory approval purposes, decision makers must also consider how these data may inform comparisons with the usual alternatives available to and used by physicians and patients in the non-trial setting.

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Association between treatment effects on disease progression (DP) endpoints and overall survival (OS) in patients with metastatic renal cell carcinoma (mRCC)

5105

Background: Access to safe and effective novel therapies may be expedited if DP endpoints (progression-free survival [PFS], time to progression [TTP], or event-free survival) are established as valid surrogates for OS in pivotal studies in mRCC. While the association between DP endpoints and OS has been established in other cancers, it has not been rigorously examined in patients with mRCC. We assessed the association between treatment effects on DP endpoints and treatment effects on OS in controlled trials of patients with mRCC. Methods: A systematic literature search was conducted (Medline, conference abstracts, references of retrieved studies/ reviews) to identify studies meeting the following criteria: controlled trials in mRCC of IL-2, IFN-α, sunitinib, sorafenib, pazopanib, bevacizumab, temsirolimus, or everolimus; English language; publication date≥1997; median time to DP and OS reported for 2 or more treatment groups. For each treatment group comparison, we calculated the differences in median time to DP and median OS and analyzed the association between the differences in median time to DP and differences in median OS using weighted ordinary least-squares (OLS) regression. Results: A total of 21 studies representing 6182 patients, 52 treatment groups, and 35 comparisons were identified. The median difference between treatment groups in time to DP averaged 1.3 months; the median difference between treatment groups in OS averaged 2.8 months. The correlation between differences in median time to DP and differences in median OS was 0.69 (p < 0.0001). In weighted OLS regression, a 1 month difference in DP was associated with a 1.4 month difference in OS (p < 0.0001, adjusted R-sq = 0.46). Conclusions: In patients receiving treatment for mRCC, treatment effects on DP endpoints are predictive of treatment effects on OS.

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Impact on disease-free survival of adjuvant erlotinib or gefitinib in patients with resected lung adenocarcinomas that harbor epidermal growth factor receptor (EGFR) mutations

7523

Background: Patients with stage IV adenocarcinoma whose tumors harbor EGFR mutations have high rates of response (∼ 75%) and prolonged progression free survival after EGFR tyrosine kinase inhibitor (TKI) treatment. Adjuvant cisplatin-based chemotherapy improves disease free survival (DFS) and overall survival (OS) in patients with resected stages IB-IIIA NSCLC. To see if adjuvant treatment with EGFR TKI (gefitinib or erlotinib) improves DFS in patients with EGFR mutation NSCLC, we conducted a retrospective review of patients with resected lung adenocarcinoma harboring EGFR mutations, some of whom received EGFR TKIs postoperatively. Methods: With Institutional Review Board approval, clinical information was obtained on all patients with stage I-III lung adenocarcinoma harboring EGFR exon 19 or 21 mutations that underwent resection at MSKCC between May 2002 and August 2008. Age, gender, type of surgery, histology, EGFR mutation status (exon 19 deletions and exon 21 L858R), stage, perioperative therapy and survival were recorded. Kaplan-Meier analysis and Cox regression analysis were performed. Results: We studied 150 patients (112 women, 38 men) with completely resected stage I-III lung adenocarcinoma whose resection specimens contained EGFR activating mutations in exon 19 or 21. Median age was 69. Forty two patients (28%) received cytotoxic chemotherapy. Forty eight (32%) received either erlotinib (n=26) or gefitinib (n=22) postoperatively. The median time on TKI was 16 months. The median DFS was 43 months in the group that received a TKI vs. 31 months for those that did not. After controlling for stage, individuals who received adjuvant gefitinib or erlotinib had a better DFS (HR=0.38, 95%CI: 0.16–0.90) than the non-TKI group (p=0.03). The median overall survival has not been reached. Conclusions: These data indicate that the adjuvant use of either gefitinib or erlotinib improves DFS in patients with completely resected stage I -III lung adenocarcinomas with mutations in EGFR exons 19 and 21. These data justify a randomized trial in similar patients.

[Table: see text]

Survival and association with time to treatment change in patients with metastatic renal cell carcinoma

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Background: Metastatic renal cell carcinoma (MRCC) is associated with high mortality rates. The objectives of this study are to examine survival rates among patients using targeted therapies (Sunitinib, Sorafenib) for MRCC and the association of time to treatment change with survival. Methods: Administrative claims data from a large, US managed care plan were used to identify commercially insured and Medicare patients with newly diagnosed MRCC from 01/01/03–12/31/07 and continuous enrollment for 12 months prior to and at least 90 days after MRCC diagnosis. Survival from earliest evidence of targeted therapy (TT) was assessed through 9/16/2008. Treatment change was defined as stopping TT, switching TT or the addition of other treatments for MRCC. Results: 253 patients were identified with newly diagnosed MRCC (average age: 60.5 years; 71.5% male) who also received TT. Mean (median) survival time from initiation of therapy was 533 (507) days. A majority of those on TT (n = 205, 81.0%) experienced treatment change within 6 months after initiating the therapy; two-thirds within 30 days of therapy initiation. Unadjusted survival rates increased significantly with longer time to change in treatment (p=0.0075), with a mean survival time of 437 days for those with treatment change within 30 days and 724 days among those with treatment change 5–6 months post therapy initiation. Conclusions: Early treatment changes are associated with shorter survival times. High rates of early treatment changes indicate inadequacies in currently available targeted therapies for MRCC patients.

No significant financial relationships to disclose.

The biological characteristics of human third trimester amniotic fluid stem cells

Third trimester amniotic fluid (AF)-derived human mesenchymal stem cells (MSCs) can be greatly expanded in vitro and induced to differentiate into multiple mesenchymal cell types. This study aimed to investigate the biological characteristics of MSCs from third trimester AF as a new source of therapeutic stem cells. Forty third trimester AF samples were obtained from healthy women who underwent elective caesarean section for breech presentation. A simple culture protocol for MSCs was used. A cell growth curve was drawn, and cell surface antigens and cytokines were analysed by immunofluorescent staining, reverse transcription-polymerase chain reaction and flow cytometry. MSCs from third-trimester AF were successfully isolated, cultured and enriched. MSCs expanded extensively without feeders, they were not tumourigenic and were induced to differentiate into osteocytes. Surface antigens were analysed and found to express the pluripotency marker Oct-4. Considering the great feasibility of biomedical engineering using MSCs, third trimester AF may provide a rich source for investigation of human MSCs.