In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

Ever since Stephen Paget’s 1889 hypothesis, metastatic organotropism has remained one of cancer’s greatest mysteries. Here we demonstrate that exosomes from mouse and human lung-, liver- and brain-tropic tumour cells fuse preferentially with resident cells at their predicted destination, namely lung fibroblasts and epithelial cells, liver Kupffer cells and brain endothelial cells. We show that tumour-derived exosomes uptaken by organ-specific cells prepare the pre-metastatic niche. Treatment with exosomes from lung-tropic models redirected the metastasis of bone-tropic tumour cells. Exosome proteomics revealed distinct integrin expression patterns, in which the exosomal integrins α6β4 and α6β1 were associated with lung metastasis, while exosomal integrin αvβ5 was linked to liver metastasis. Targeting the integrins α6β4 and αvβ5 decreased exosome uptake, as well as lung and liver metastasis, respectively. We demonstrate that exosome integrin uptake by resident cells activates Src phosphorylation and pro-inflammatory S100 gene expression. Finally, our clinical data indicate that exosomal integrins could be used to predict organ-specific metastasis.

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Colorectal cancer patients with EGFR-negative tumors have the potential to respond to cetuximab-based therapies. EGFR analysis by current IHC techniques does not seem to have predictive value, and selection or exclusion of patients for cetuximab therapy on the basis of currently available EGFR IHC does not seem warranted.

Context Some melanomas arising from acral, mucosal, and chronically sun-damaged sites harbor activating mutations and amplification of the type III transmembrane receptor tyrosine kinase KIT. We explored the effects of KIT inhibition using imatinib mesylate in this molecular subset of disease. Objective To assess clinical effects of imatinib mesylate in patients with melanoma harboring KIT alterations. Design, Setting, and Patients A single-group, open-label, phase 2 trial at 1 community and 5 academic oncology centers in the United States of 295 patients with melanoma screened for the presence of KIT mutations and amplification between April 23, 2007, and April 16, 2010. A total of 51 cases with such alterations were identified and 28 of these patients were treated who had advanced unresectable melanoma arising from acral, mucosal, and chronically sun-damaged sites. Intervention Imatinib mesylate, 400 mg orally twice daily. Main Outcome Measures Radiographic response, with secondary end points including time to progression, overall survival, and correlation of molecular alterations and clinical response. Results Two complete responses lasting 94 (ongoing) and 95 weeks, 2 durable partial responses lasting 53 and 89 (ongoing) weeks, and 2 transient partial responses lasting 12 and 18 weeks among the 25 evaluable patients were observed. The overall durable response rate was 16% (95% confidence interval [CI], 2%–30%), with a median time to progression of 12 weeks (interquartile range [IQR], 6–18 weeks; 95% CI, 11–18 weeks), and a median overall survival of 46.3 weeks (IQR, 28 weeks-not achieved; 95% CI, 28 weeks-not achieved). Response rate was better in cases with mutations affecting recurrent hotspots or with a mutant to wild-type allelic ratio of more than 1 (40% vs 0%, P=.05), indicating positive selection for the mutated allele. Conclusions Among patients with advanced melanoma harboring KIT alterations, treatment with imatinib mesylate results in significant clinical responses in a subset of patients. Responses may be limited to tumors harboring KIT alterations of proven functional relevance.

The cell cycle represents a series of tightly integrated events that allow the cell to grow and proliferate. Critical parts of the cell cycle machinery are the cyclin-dependent kinases (CDKs), which, when activated, provide a means for the cell to move from one phase of the cell cycle to the next. The CDKs are regulated positively by cyclins and regulated negatively by naturally occurring CDK inhibitors (CDKIs). Cancer represents a dysregulation of the cell cycle such that cells that overexpress cyclins or do not express the CDKIs continue to undergo unregulated cell growth. The cell cycle also serves to protect the cell from DNA damage. Thus, cell cycle arrest, in fact, represents a survival mechanism that provides the tumor cell the opportunity to repair its own damaged DNA. Thus, abrogation of cell cycle checkpoints, before DNA repair is complete, can activate the apoptotic cascade, leading to cell death. Now in clinical trials are a series of targeted agents that directly inhibit the CDKs, inhibit unrestricted cell growth, and induce growth arrest. Recent attention has also focused on these drugs as inhibitors of transcription. In addition, there are now agents that abrogate the cell cycle checkpoints at critical time points that make the tumor cell susceptible to apoptosis. An understanding of the cell cycle is critical to understanding how best to clinically develop these agents, both as single agents and in combination with chemotherapy.

Alliance Clinical Trials in Oncology, National Cancer Institute Cancer Therapy Evaluation Program, Bristol-Myers Squibb, Cycle for Survival.

Background Median overall survival for patients with metastatic soft tissue sarcoma is 12 to 16 months. Olaratumab is a human anti–platelet-derived growth factor receptor α monoclonal antibody which has antitumour activity in human sarcoma xenografts. Methods We conducted an open-label phase 1b, randomised, phase 2 study of doxorubicin ± olaratumab in patients with unresectable/metastatic soft tissue sarcoma. The phase 1b primary endpoint was safety; the phase 2 primary endpoint was progression-free survival using a two-sided alpha level of 0·2 and statistical power of 0·8. This study was registered with ClinicalTrials.gov, number NCT01185964. Findings Fifteen patients were enrolled and treated with olaratumab+doxorubicin in the phase 1b portion; 133 patients were randomised (66 to olaratumab+doxorubicin; 67 to doxorubicin) in the phase 2 portion, 129 of whom (97%) received at least one dose of study treatment (64 olaratumab+doxorubicin; 65 doxorubicin). Median progression-free survival in phase 2 was 6·6 months (95% confidence interval [CI], 4·1–8·3) with olaratumab+doxorubicin and 4·1 months (95% CI, 2·8–5·4) with doxorubicin (stratified hazard ratio [HR], 0·672; 95% CI, 0·442–1·021; p=0·0615). Median overall survival was 26·5 months (95% CI, 20·9–31·7) with olaratumab+doxorubicin and 14·7 months (95% CI, 9·2–17·1) with doxorubicin (stratified HR, 0·463; 95% CI, 0·301–0·710; p=0·0003). Adverse events more frequent with olaratumab+doxorubicin vs doxorubicin alone included neutropenia (38 [59%] vs 25 [39%]), mucositis (34 [53%] vs 23 [35%]), nausea (47 [73%] vs 34 [52%]), vomiting (29 [45%] vs 12 [19%]), and diarrhea (22 [34%] vs 15 [23%]). Febrile neutropenia of grade ≥3 was similar in both groups (olaratumab plus doxorubicin 8 (13%) vs doxorubicin 9 (14%). Interpretation This study of olaratumab with doxorubicin in patients with advanced soft tissue sarcoma met its predefined primary endpoint for progression-free survival and achieved a highly significant improvement of 11·8 months in median overall survival (P=0·0003; HR 0·46). Funding Eli Lilly and Company.