Efficacy, tolerability, and biomarker analyses from a phase III, randomized, placebo-controlled, parallel group study of gefitinib as maintenance therapy in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC; INFORM; C-TONG 0804)

LBA7511

Background: INFORM (a phase III, randomized, multicenter, parallel group study; NCT00770588 ) investigated the efficacy, safety and tolerability of gefitinib (G) vs. placebo (P) as maintenance therapy in pts with locally advanced/metastatic NSCLC following standard first-line platinum based chemotherapy. Methods: Pts (≥18 years, with stage IIIB/IV NSCLC and WHO performance status 0-2) had completed 4 cycles of first-line platinum based doublet chemotherapy without progression/unacceptable toxicity. Pts were randomized 1:1 to G 250mg/day or P on discontinuation of first-line therapy. Progression-free survival (PFS; primary endpoint) was assessed in the intent to treat population (Cox proportional hazards adjusted for histology [adenocarcinoma vs. non-adenocarcinoma], smoking status [never-smoker vs. smoker], EGFR mutation status [positive vs. negative vs. unknown] and best response to first-line chemotherapy [complete response/partial response vs. stable disease]). PFS was considered superior with gefitinib if the G:P hazard ratio (HR) upper confidence interval (CI) was <1.00. Secondary endpoints included overall survival (OS), objective response rate, disease control rate, symptom improvement and tolerability. Results: 296 pts (n=148 G, n=148 P) were randomized (27 centers in china; 26 September 2008-10 August 2009). PFS data cutoff on 24 January 2011. Median duration of follow-up was 16.8 months: 91% pts progressed; 59% deaths. Demography was balanced between treatments; overall, 54.1% pts were never-smokers, 70.6% had adenocarcinoma, and 40.9% were female. For G vs. P, PFS HR=0.42; 95% CI 0.32-0.54; p<0.0001; median PFS 4.8 vs. 2.6 months. Most common AEs (any grade) with G were rash (49.7%), diarrhea (25.2%), and ALT increase (21.1%) which were generally mild/moderate. Overall incidence of serious AEs: G (6.8%); P (3.4%). Other secondary endpoint data (including OS and biomarkers) will be presented. Conclusions: PFS was significantly longer with G compared with P as maintenance therapy in Chinese patients with locally advanced NSCLC.

C10ORF97 is a novel tumor-suppressor gene of non-small-cell lung cancer and a functional variant of this gene increases the risk of non-small-cell lung cancer

In an earlier study we showed that C10ORF97 (chromosome-10, open reading frame-97) was expressed in almost all of the tissues and cell lines tested, and that it inhibited the growth of seven tumor cell lines, including two lung carcinoma cell lines (A549 and PG). Here, we show that C10ORF97 is downregulated in non-small-cell lung cancer (NSCLC) tissue compared with normal lung tissue. Overexpression of C10ORF97 significantly suppressed human lung carcinoma A549 cell growth (proliferation and anchorage-independent growth in soft agar) and motility (migration and adhesion). This tumor-suppressive function of C10ORF97 was also verified in vivo. We further found that C10ORF97 caused G(1) arrest of A549 cells and modulated the expression level of several cell-cycle regulators (such as CDK2, cyclin-E and p27). These effects of C10ORF97 were mediated by physical association between C10ORF97 and Jun-activating domain-binding protein-1 (JAB1), and blocking of JAB1-mediated translocation of p27 from the nucleus to the cytoplasm. Together, these results indicated that C10ORF97 functions as a novel tumor suppressor by modulating several key G(1)/S-regulatory proteins by interacting with JAB1. These findings led us to hypothesize that a single-nucleotide polymorphism (SNP) in the C10ORF97 gene that affects its expression might be associated with susceptibility to NSCLC. SNP216 C>T (rs2297882) in the C10ORF97 Kozak sequence was identified, and allele T of SNP216 suppressed C10ORF97 expression in vitro and in vivo. Furthermore, the TT genotype of SNP216 was associated with an increased risk of NSCLC (adjusted odds ratio=1.73 (95% confidence interval: 1.33-2.25), P=4.6 × 10(-5)). These data indicated that C10ORF97 is a tumor suppressor of NSCLC progression and C10ORF97-SNP216 may serve as a predictor of NSCLC.

Abstract P2-12-02: How Common Is Sexual Dysfunction among Women with Early Stage Breast Cancer?

Background: Despite the high prevalence of sexual problems (50—90%) among women with early stage breast cancer (EBC), relatively little is known about the prevalence of clinically significant post-systemic treatment sexual dysfunction (SD) and its impact on quality of life (QOL). According to the American Psychiatric Association (APA), SD consists of sexual problems causing marked personal distress. While 40% of healthy US women report sexual problems, only 12% experience SD. No study has applied the APA criterion to document the prevalence of SD in women with EBC who have completed systemic therapy. The goal of this study is to address this gap and to examine some correlates (anxious predispositions and menopausal symptoms) of SD and the impact of SD on QOL. Methods: Post-menopausal women receiving cancer therapy for EBC or early colon cancer were approached for this study. Sexual problems were evaluated with the Female Sexual Function Index while sexual distress was assessed with the Female Sexual Distress Scale. QOL was measured with FACT-B, using its endocrine symptoms subscale (ES) to assess menopausal symptoms. Spielberger State-Trait Anxiety Inventory measured anxious predispositions. Participants completed questionnaires upon completion of adjuvant chemotherapy but prior to initiation of hormonal therapy (estrogen sensitive EBC). SD was assessed using the APA classification. Results: Between January 2009 and May 1 2010, 70 EBC patients entered this study. The proportion of women (mean age 61) reporting 1 or more sexual problems was high (93%) and included problems with 1) frequency (66%) and level (65%) of sexual desire, 2) frequency (66%), level (52%) and satisfaction (43%) of arousal, 3) frequency (21%) of vaginal dryness and difficulty becoming lubricated (47%) during sexual activity, 4) satisfaction with their sexual life (30%) and 5) pain during intercourse (18%). However, the APA criterion identified only 30% of patients as having SD. Multiple logistic regression showed that anxiety predispositions and menopausal symptoms predicted SD (p&lt; .01). Women classified as having SD had higher anxiety scores (No SD=34 SD=41, p&lt;.05) as well as higher levels of menopausal symptoms (i.e, lower ES scores; No SD= 62 SD=54, p&lt;.01). QOL was negatively impacted by SD (r=-0.42, p&lt;.01). Discussion: Despite the fact that an overwhelming majority of patients had sexual difficulties, the APA distress criterion identified far fewer patients (30 %) with SD. Nevertheless, we found a high prevalence rate of SD, which was 2.5 times higher (%2 &lt; .01) than that reported in women without a cancer diagnosis. Women with anxious predispositions and high menopausal symptoms may be at risk for SD and may benefit from early interventions to prevent SD.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-12-02.

Arrestin-1 expression level in rods: balancing functional performance and photoreceptor health

In rod photoreceptors, signaling persists as long as rhodopsin remains catalytically active. Phosphorylation by rhodopsin kinase followed by arrestin-1 binding completely deactivates rhodopsin. Timely termination prevents excessive signaling and ensures rapid recovery. Mouse rods express arrestin-1 and rhodopsin at ∼0.8:1 ratio, making arrestin-1 the second most abundant protein in the rod. The biological significance of wild type arrestin-1 expression level remains unclear. Here we investigated the effects of varying arrestin-1 expression on its intracellular distribution in dark-adapted photoreceptors, rod functional performance, recovery kinetics, and morphology. We found that rod outer segments isolated from dark-adapted animals expressing arrestin-1 at wild type or higher level contain much greater fraction of arrestin-1 than previously estimated, 15-25% of the total. The fraction of arrestin-1 residing in the outer segments (OS) in animals with low expression (4-12% of wild type) is much lower, 5-7% of the total. Only 4% of wild type arrestin-1 level in the outer segments was sufficient to maintain near-normal retinal morphology, whereas rapid recovery required at least ∼12%. Supra-physiological arrestin-1 expression improved light sensitivity and facilitated photoresponse recovery, but was detrimental for photoreceptor health, particularly in the peripheral retina. Thus, physiological level of arrestin-1 expression in rods reflects the balance between short-term functional performance of photoreceptors and their long-term health.

BP neural network classification for bleeding detection in wireless capsule endoscopy

Bleeding in the digestive tract is one of the most common gastrointestinal tract (GI) diseases, as well as the complication of some fatal diseases. Wireless capsule endoscopy (WCE) allows physicians to noninvasively examine the entire GI tract. However it is very laborious and time-consuming to inspect large numbers of WCE images, which limits the wider application of WCE. It is therefore important to develop an automatic and intelligent computer-aided bleeding detection technique. In this paper, a new method aimed at bleeding detection in WCE images is proposed. Colour texture features distinguishing the bleeding regions from non-bleeding regions are extracted in RGB and HSI colour spaces; then a neural network using the colour texture features as the feature vector inputs is designed to recognize the bleeding regions. The experiments demonstrate that the bleeding regions can be correctly recognized and clearly marked out. The sensitivity of the algorithm is 93% and the specificity is 96%.

Functional expression of large-conductance Ca2+-activated potassium channels in lateral globus pallidus neurons

The presence of large-conductance Ca(2+)-activated potassium (BK) channels, which are considered to play an important role in the excitability of neurons, in the highly-excitable lateral globus pallidus (LGP) neurons has yet to be confirmed. In this study, we confirmed the functional expression of BK channels in mouse LGP neurons and investigated the characteristics of their single-channel currents using inside-out patch-clamp recordings. These BK channels had a conductance of 276 pS, were activated by the elevation of both the transmembrane potential and intracellular calcium concentration ([Ca(2+)](i)), and were completely blocked by the BK channel-specific blocker paxilline (100 nM). In addition, the channel currents were sensitive to high-energy phosphate compounds and low internal pH. The cellular function of these BK channels was then investigated by nystatin-perforated whole-cell recording. Paxilline (100 nM) had no effect on the frequency and half-width of the action potential (AP) in LGP neurons under control conditions, but significantly attenuated the hyperpolarization that was caused by carbonyl cyanide m-chlorophenylhydrazone (CCCP), an inhibitor of ATP synthesis. In addition, the pancreatic beta-cell type ATP-sensitive potassium channel (K(ATP) channel) blocker tolbutamide (0.25 mM) also attenuated the hyperpolarization, in a manner similar to paxilline. The voltage-dependent potassium channel blocker tetraethylammonium (TEA, 2 mM) significantly decreased the frequency and increased the half-width of the AP in LGP neurons under control conditions, and attenuated CCCP-induced hyperpolarization to an extent close to that of paxilline. The results presented here suggest that functional BK channels are present in LGP neurons, and may behave as partners of K(ATP) channels in the regulation of neuronal activity under metabolic stress conditions.