The chromosome breakage-fusion-bridge (BFB) cycle is a mutational process that produces gene amplification and genome instability. Signatures of BFB cycles can be observed in cancer genomes alongside ...chromothripsis, another catastrophic mutational phenomenon. We explain this association by elucidating a mutational cascade that is triggered by a single cell division error-chromosome bridge formation-that rapidly increases genomic complexity. We show that actomyosin forces are required for initial bridge breakage. Chromothripsis accumulates, beginning with aberrant interphase replication of bridge DNA. A subsequent burst of DNA replication in the next mitosis generates extensive DNA damage. During this second cell division, broken bridge chromosomes frequently missegregate and form micronuclei, promoting additional chromothripsis. We propose that iterations of this mutational cascade generate the continuing evolution and subclonal heterogeneity characteristic of many human cancers.
Overall survival rates for patients with advanced osteosarcoma have remained static for over three decades. An in vitro analysis of osteosarcoma cell lines for sensitivity to an array of approved ...cancer therapies revealed that panobinostat, a broad spectrum histone deacetalyase (HDAC) inhibitor, is highly effective at triggering osteosarcoma cell death. Using in vivo models of orthotopic and metastatic osteosarcoma, here we report that panobinostat impairs the growth of primary osteosarcoma in bone and spontaneous metastasis to the lung, the most common site of metastasis for this disease. Further, pretreatment of mice with panobinostat prior to tail vein inoculation of osteosarcoma prevents the seeding and growth of lung metastases. Additionally, panobinostat impaired the growth of established lung metastases and improved overall survival, and these effects were also manifest in the lung metastatic SAOS2‐LM7 model. Mechanistically, the efficacy of panobinostat was linked to high expression of HDAC1 and HDAC2 in osteosarcoma, and silencing of HDAC1 and 2 greatly reduced osteosarcoma growth in vitro. In accordance with these findings, treatment with the HDAC1/2 selective inhibitor romidepsin compromised the growth of osteosarcoma in vitro and in vivo. Analysis of patient‐derived xenograft osteosarcoma cell lines further demonstrated the sensitivity of the disease to panobinostat or romidepsin. Collectively, these studies provide rationale for clinical trials in osteosarcoma patients using the approved therapies panobinostat or romidepsin.
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Clinical trials of osteosarcoma therapies are difficult to conduct given the low incidence of the disease. While in vitro studies have identified histone deacetylase (HDAC) inhibitors as a potential treatment, their efficacy in vivo largely remains untested. This study found that the broad‐spectrum HDAC inhibitor panobinostat blocks spontaneous osteosarcoma metastasis to the lung when used as a single agent. Panobinostat also impaired growth of established lung metastases and improved overall survival. Mechanistically, HDAC1/2 emerged as important drivers of osteosarcoma growth and metastasis. Altogether, the findings provide a strong rationale for the design of clinical trials to test panobinostat in humans.
Epidermal growth factor receptor inhibitors (EGFRIs) have demonstrated improved overall survival in patients with non‐small cell lung cancer, pancreatic cancer, and colorectal cancer; however, their ...use is associated with dermatologic reactions of varying severity. The similar spectrum of events observed with monoclonal antibodies and tyrosine kinase inhibitors suggests such toxicities are a class effect. While such reactions do not necessarily require any alteration in EGFRI treatment, being best addressed through symptomatic treatment, there is limited evidence on which to base such therapies. In October 2006, at an international and interdisciplinary EGFRI dermatologic toxicity forum, the underlying mechanisms of these toxicities were discussed and commonly used therapeutic interventions were evaluated. Our aim was to reach a current consensus on management strategies. A three‐tiered, EGFRI‐focused toxicity grading system is suggested for the purposes of therapeutic decision making, and as a framework on which to build a stepwise approach to intervention. This approach to successful management is specifically tailored to accurately categorize dermatologic toxicity associated with EGFRIs, and can be easily applied by all health care professionals. The goal is to maximize quality of life in patients who are being treated with these agents—many of whom will be on these drugs for several months or even years.
Disclosure of potential conflicts of interest is found at the end of this article.
Ipilimumab, which is an anti-cytotoxic T-cell lymphocyte-4 monoclonal antibody, showed a survival benefit in melanoma with adverse events (AEs) managed by protocol-defined guidelines. A phase II ...study in lung cancer assessed the activity of ipilimumab plus paclitaxel and carboplatin.
Patients (N = 204) with chemotherapy-naive non-small-cell lung cancer (NSCLC) were randomly assigned 1:1:1 to receive paclitaxel (175 mg/m(2)) and carboplatin (area under the curve, 6) with either placebo (control) or ipilimumab in one of the following two regimens: concurrent ipilimumab (four doses of ipilimumab plus paclitaxel and carboplatin followed by two doses of placebo plus paclitaxel and carboplatin) or phased ipilimumab (two doses of placebo plus paclitaxel and carboplatin followed by four doses of ipilimumab plus paclitaxel and carboplatin).Treatment was administered intravenously every 3 weeks for ≤ 18 weeks (induction). Eligible patients continued ipilimumab or placebo every 12 weeks as maintenance therapy. Response was assessed by using immune-related response criteria and modified WHO criteria. The primary end point was immune-related progression-free survival (irPFS). Other end points were progression-free survival (PFS), best overall response rate (BORR), immune-related BORR (irBORR), overall survival (OS), and safety.
The study met its primary end point of improved irPFS for phased ipilimumab versus the control (hazard ratio HR, 0.72; P = .05), but not for concurrent ipilimumab (HR, 0.81; P = .13). Phased ipilimumab also improved PFS according to modified WHO criteria (HR, 0.69; P = .02). Phased ipilimumab, concurrent ipilimumab, and control treatments were associated with a median irPFS of 5.7, 5.5, and 4.6 months, respectively, a median PFS of 5.1, 4.1, and 4.2 months, respectively, an irBORR of 32%, 21% and 18%, respectively, a BORR of 32%, 21% and 14%, respectively, and a median OS of 12.2, 9.7, and 8.3 months. Overall rates of grade 3 and 4 immune-related AEs were 15%, 20%, and 6% for phased ipilimumab, concurrent ipilimumab, and the control, respectively. Two patients (concurrent, one patient; control, one patient) died from treatment-related toxicity.
Phased ipilimumab plus paclitaxel and carboplatin improved irPFS and PFS, which supports additional investigation of ipilimumab in NSCLC.
CONTEXT More persons in the United States die from non–small cell lung
cancer (NSCLC) than from breast, colorectal, and prostate cancer combined.
In preclinical testing, oral gefitinib inhibited the ...growth of NSCLC tumors
that express the epidermal growth factor receptor (EGFR), a mediator of cell
signaling, and phase 1 trials have demonstrated that a fraction of patients
with NSCLC progressing after chemotherapy experience both a decrease in lung
cancer symptoms and radiographic tumor shrinkages with gefitinib. OBJECTIVE To assess differences in symptomatic and radiographic response among
patients with NSCLC receiving 250-mg and 500-mg daily doses of gefitinib. DESIGN, SETTING, AND PATIENTS Double-blind, randomized phase 2 trial conducted from November 2000
to April 2001 in 30 US academic and community oncology centers. Patients (N
= 221) had either stage IIIB or IV NSCLC for which they had received at least
2 chemotherapy regimens. INTERVENTION Daily oral gefitinib, either 500 mg (administered as two 250-mg gefitinib
tablets) or 250 mg (administered as one 250-mg gefitinib tablet and 1 matching
placebo). MAIN OUTCOME MEASURES Improvement of NSCLC symptoms (2-point or greater increase in score
on the summed lung cancer subscale of the Functional Assessment of Cancer
Therapy-Lung FACT-L instrument) and tumor regression (>50% decrease in lesion
size on imaging studies). RESULTS Of 221 patients enrolled, 216 received gefitinib as randomized. Symptoms
of NSCLC improved in 43% (95% confidence interval CI, 33%-53%) of patients
receiving 250 mg of gefitinib and in 35% (95% CI, 26%-45%) of patients receiving
500 mg. These benefits were observed within 3 weeks in 75% of patients. Partial
radiographic responses occurred in 12% (95% CI, 6%-20%) of individuals receiving
250 mg of gefitinib and in 9% (95% CI, 4%-16%) of those receiving 500 mg.
Symptoms improved in 96% of patients with partial radiographic responses.
The overall survival at 1 year was 25%. There were no significant differences
between the 250-mg and 500-mg doses in rates of symptom improvement (P = .26), radiographic tumor regression (P = .51), and projected 1-year survival (P =
.54). The 500-mg dose was associated more frequently with transient acne-like
rash (P = .04) and diarrhea (P = .006). CONCLUSIONS Gefitinib, a well-tolerated oral EGFR-tyrosine kinase inhibitor, improved
disease-related symptoms and induced radiographic tumor regressions in patients
with NSCLC persisting after chemotherapy.
The EML4-ALK fusion oncogene represents a novel molecular target in a small subset of non-small-cell lung cancers (NSCLC). To aid in identification and treatment of these patients, we examined the ...clinical characteristics and treatment outcomes of patients who had NSCLC with and without EML4-ALK.
Patients with NSCLC were selected for genetic screening on the basis of two or more of the following characteristics: female sex, Asian ethnicity, never/light smoking history, and adenocarcinoma histology. EML4-ALK was identified by using fluorescent in situ hybridization for ALK rearrangements and was confirmed by immunohistochemistry for ALK expression. EGFR and KRAS mutations were determined by DNA sequencing.
Of 141 tumors screened, 19 (13%) were EML4-ALK mutant, 31 (22%) were EGFR mutant, and 91 (65%) were wild type (WT/WT) for both ALK and EGFR. Compared with the EGFR mutant and WT/WT cohorts, patients with EML4-ALK mutant tumors were significantly younger (P < .001 and P = .005) and were more likely to be men (P = .036 and P = .039). Patients with EML4-ALK-positive tumors, like patients who harbored EGFR mutations, also were more likely to be never/light smokers compared with patients in the WT/WT cohort (P < .001). Eighteen of the 19 EML4-ALK tumors were adenocarcinomas, predominantly the signet ring cell subtype. Among patients with metastatic disease, EML4-ALK positivity was associated with resistance to EGFR tyrosine kinase inhibitors (TKIs). Patients in the EML4-ALK cohort and the WT/WT cohort showed similar response rates to platinum-based combination chemotherapy and no difference in overall survival.
EML4-ALK defines a molecular subset of NSCLC with distinct clinical characteristics. Patients who harbor this mutation do not benefit from EGFR TKIs and should be directed to trials of ALK-targeted agents.
Multitargeted agents represent the next generation of targeted therapies in solid tumors. The benefits of individually targeting the vascular endothelial growth factor receptor (VEGFR) and epidermal ...growth factor receptor (EGFR) signaling pathways have been clinically validated in recent years in a number of solid tumor types including non‐small cell lung cancer (NSCLC). Given the heterogeneity of this tumor type and potential crosstalk between these key signaling pathways (which are known to play a critical role in tumor growth, metastasis, and angiogenesis), dual inhibition of the VEGFR and EGFR signaling pathways has the potential to offer additional clinical benefits in NSCLC. A number of approaches to inhibiting both VEGFR and EGFR signaling are currently under investigation, including monotherapy with a multitargeted tyrosine kinase inhibitor (e.g., vandetanib, AEE788, XL647, BMS‐690514) or a combination of single‐targeted therapies (e.g., bevacizumab, cetuximab, erlotinib, gefitinib). Preclinical and early clinical data (phase I and II trials) support combined inhibition of the VEGFR and EGFR pathways in NSCLC. Overall, combined inhibition strategies are well tolerated and have shown promise in early clinical studies. Ongoing phase II and phase III trials will determine the clinical potential of a number of dual inhibition strategies in the treatment of advanced NSCLC.
This manuscript focuses on the clinical potential for inhibition of both the vascular endothelial growth factor receptor and the epidermal growth factor receptor signaling pathways in non‐small cell lung cancer. The authors describe the rationale and strategies to achieve dual inhibition and summarize key clinical data and ongoing investigations.
Understanding of prognosis among terminally ill patients impacts medical decision making. The aims of this study were to explore perceptions of prognosis and goals of therapy in patients with ...metastatic non-small-cell lung cancer (NSCLC) and to examine the effect of early palliative care on these views over time.
Patients with newly diagnosed metastatic NSCLC were randomly assigned to receive either early palliative care integrated with standard oncology care or standard oncology care alone. Participants completed baseline and longitudinal assessments of their perceptions of prognosis and the goals of cancer therapy over a 6-month period.
We enrolled 151 participants on the study. Despite having terminal cancer, one third of patients (46 of 145 patients) reported that their cancer was curable at baseline, and a majority (86 of 124 patients) endorsed getting rid of all of the cancer as a goal of therapy. Baseline perceptions of prognosis (ie, curability) and goals of therapy did not differ significantly between study arms. A greater percentage of patients assigned to early palliative care retained or developed an accurate assessment of their prognosis over time (82.5% v 59.6%; P = .02) compared with those receiving standard care. Patients receiving early palliative care who reported an accurate perception of their prognosis were less likely to receive intravenous chemotherapy near the end of life (9.4% v 50%; P = .02).
Many patients with newly diagnosed metastatic NSCLC hold inaccurate perceptions of their prognoses. Early palliative care significantly improves patient understanding of prognosis over time, which may impact decision making about care near the end of life.
Summary Background Observational studies report reduced colorectal cancer in regular aspirin consumers. Randomised controlled trials have shown reduced risk of adenomas but none have employed ...prevention of colorectal cancer as a primary endpoint. The CAPP2 trial aimed to investigate the antineoplastic effects of aspirin and a resistant starch in carriers of Lynch syndrome, the major form of hereditary colorectal cancer; we now report long-term follow-up of participants randomly assigned to aspirin or placebo. Methods In the CAPP2 randomised trial, carriers of Lynch syndrome were randomly assigned in a two-by-two factorial design to 600 mg aspirin or aspirin placebo or 30 g resistant starch or starch placebo, for up to 4 years. Randomisation was in blocks of 16 with provision for optional single-agent randomisation and extended postintervention double-blind follow-up; participants and investigators were masked to treatment allocation. The primary endpoint was development of colorectal cancer. Analysis was by intention to treat and per protocol. This trial is registered, ISRCTN59521990. Results 861 participants were randomly assigned to aspirin or aspirin placebo. At a mean follow-up of 55·7 months, 48 participants had developed 53 primary colorectal cancers (18 of 427 randomly assigned to aspirin, 30 of 434 to aspirin placebo). Intention-to-treat analysis of time to first colorectal cancer showed a hazard ratio (HR) of 0·63 (95% CI 0·35–1·13, p=0·12). Poisson regression taking account of multiple primary events gave an incidence rate ratio (IRR) of 0·56 (95% CI 0·32–0·99, p=0·05). For participants completing 2 years of intervention (258 aspirin, 250 aspirin placebo), per-protocol analysis yielded an HR of 0·41 (0·19–0·86, p=0·02) and an IRR of 0·37 (0·18–0·78, p=0·008). No data for adverse events were available postintervention; during the intervention, adverse events did not differ between aspirin and placebo groups. Interpretation 600 mg aspirin per day for a mean of 25 months substantially reduced cancer incidence after 55·7 months in carriers of hereditary colorectal cancer. Further studies are needed to establish the optimum dose and duration of aspirin treatment. Funding European Union; Cancer Research UK; Bayer Corporation; National Starch and Chemical Co; UK Medical Research Council; Newcastle Hospitals trustees; Cancer Council of Victoria Australia; THRIPP South Africa; The Finnish Cancer Foundation; SIAK Switzerland; Bayer Pharma.
Lung cancers harboring mutations in the epidermal growth factor receptor (EGFR) respond to EGFR tyrosine kinase inhibitors, but drug resistance invariably emerges. To elucidate mechanisms of acquired ...drug resistance, we performed systematic genetic and histological analyses of tumor biopsies from 37 patients with drug-resistant non-small cell lung cancers (NSCLCs) carrying EGFR mutations. All drug-resistant tumors retained their original activating EGFR mutations, and some acquired known mechanisms of resistance including the EGFR T790M mutation or MET gene amplification. Some resistant cancers showed unexpected genetic changes including EGFR amplification and mutations in the PIK3CA gene, whereas others underwent a pronounced epithelial-to-mesenchymal transition. Surprisingly, five resistant tumors (14%) transformed from NSCLC into small cell lung cancer (SCLC) and were sensitive to standard SCLC treatments. In three patients, serial biopsies revealed that genetic mechanisms of resistance were lost in the absence of the continued selective pressure of EGFR inhibitor treatment, and such cancers were sensitive to a second round of treatment with EGFR inhibitors. Collectively, these results deepen our understanding of resistance to EGFR inhibitors and underscore the importance of repeatedly assessing cancers throughout the course of the disease.
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