Transient, multi-protein complexes are important facilitators of cellular functions. This includes the chaperome, an abundant protein family comprising chaperones, co-chaperones, adaptors, and folding enzymes—dynamic complexes of which regulate cellular homeostasis together with the protein degradation machinery1–6. Numerous studies have addressed the role of chaperome members in isolation, yet little is known about their relationships regarding how they interact and function together in malignancy7–17. As function is probably highly dependent on endogenous conditions found in native tumours, chaperomes have resisted investigation, mainly due to the limitations of methods needed to disrupt or engineer the cellular environment to facilitate analysis. Such limitations have led to a bottleneck in our understanding of chaperome-related disease biology and in the development of chaperome-targeted cancer treatment. Here we examined the chaperome complexes in a large set of tumour specimens. The methods used maintained the endogenous native state of tumours and we exploited this to investigate the molecular characteristics and composition of the chaperome in cancer, the molecular factors that drive chaperome networks to crosstalk in tumours, the distinguishing factors of the chaperome in tumours sensitive to pharmacologic inhibition, and the characteristics of tumours that may benefit from chaperome therapy. We find that under conditions of stress, such as malignant transformation fuelled by MYC, the chaperome becomes biochemically ‘rewired’ to form a network of stable, survival-facilitating, high-molecular-weight complexes. The chaperones heat shock protein 90 (HSP90) and heat shock cognate protein 70 (HSC70) are nucleating sites for these physically and functionally integrated complexes. The results indicate that these tightly integrated chaperome units, here termed the epichaperome, can function as a network to enhance cellular survival, irrespective of tissue of origin or genetic background. The epichaperome, present in over half of all cancers tested, has implications for diagnostics and also provides potential vulnerability as a target for drug intervention.

The rates of tumor growth during active surveillance in a US cohort with PTCs measuring 1.5 cm or less were low. Serial measurement of tumor volumes may facilitate early identification of tumors that will continue to grow and thereby inform the timing of surveillance imaging and therapeutic interventions.

Background: The Bethesda System for Reporting Thyroid Cytopathology is the standard for interpreting fine needle aspiration (FNA) specimens. The ''atypia of undetermined significance/follicular lesion of undetermined significance'' (AUS/FLUS) category, known as Bethesda Category III, has been ascribed a malignancy risk of 5-15%, but the probability of malignancy in AUS/FLUS specimens remains unclear. Our objective was to determine the risk of malignancy in thyroid FNAs categorized as AUS/FLUS at a comprehensive cancer center. Methods: The management of 541 AUS/FLUS thyroid nodule patients treated at Memorial Sloan-Kettering Cancer Center between 2008 and 2011 was analyzed. Clinical and radiologic features were examined as predictors for surgery. Target AUS/FLUS nodules were correlated with surgical pathology. Results: Of patients with an FNA initially categorized as AUS/FLUS, 64.7% (350/541) underwent immediate surgery, 17.7% (96/541) had repeat FNA, and 17.6% (95/541) were observed. Repeat FNA cytology was unsatisfactory in 5.2% (5/96), benign in 42.7% (41/96), AUS/FLUS in 38.5% (37/96), suspicious for follicular neoplasm in 5.2% (5/96), suspicious for malignancy in 4.2% (4/96), and malignant in 4.2% (4/96). Of nodules with two consecutive AUS/FLUS diagnoses that were resected, 26.3% (5/19) were malignant. Among all index AUS/FLUS nodules (triaged to surgery, repeat FNA, or observation), malignancy was confirmed on surgical pathology in 26.6% . Among AUS/FLUS nodules triaged to surgery, the malignancy rate was 37.8% . Incidental cancers were found in 22.3% of patients. On univariate logistic regression analysis, factors associated with triage to surgery were younger patient age ( p < 0.0001), increasing nodule size ( p < 0.0001), and nodule hypervascularity ( p = 0.032). Conclusions: In patients presenting to a comprehensive cancer center, malignancy rates in nodules with AUS/ FLUS cytology are higher than previously estimated, with 26.6-37.8% of AUS/FLUS nodules harboring cancer. These data imply that Bethesda Category III nodules in some practice settings may have a higher risk of malignancy than traditionally believed, and that guidelines recommending repeat FNA or observation merit reconsideration.

Purpose: To better direct targeted therapies to the patients with tumors that express the target, there is an urgent need for blood-based assays that provide expression information on a consistent basis in real time with minimal patient discomfort.We aimed to use immunomagnetic-capture technology to isolate and analyze circulating tumor cells (CTC) from small volumes of peripheral blood of patients with advanced prostate cancer. Experimental Design: Blood was collected from 63 patients with metastatic prostate cancer. CTCs were isolated by the CellSearch system, which uses antibodies to epithelial cell adhesion marker and immunomagnetic capture. CTCs were defined as nucleated cells positive for cytokeratins and negative for CD45. Captured cells were analyzed by immunofluorescence, Papanicolau staining, and fluorescence in situ hybridization. Results: Most patients (65%) had 5 or more CTCs per 7.5 mL blood sample. Cell counts were consistent between laboratories (c = 0.99) and did not change significantly over 72 or 96 h of storage before processing (c = 0.99). Their identity as prostate cancer cells was confirmed by conventional cytologic analysis. Molecular profiling, including analysis of epidermal growth factor receptor (EGFR) expression, chromosome ploidy, and androgen receptor (AR) gene amplification, was possible for all prostate cancer patients with z5 CTCs. Conclusions: The analysis of cancer-related alterations at the DNA and protein level from CTCs is feasible in a hospital-based clinical laboratory. The alterations observed in EGFR and AR suggest that the methodology may have a role in clinical decision making.

A B S T R A C T PurposeWe sought to define the prevalence and co-occurrence of actionable genomic alterations in patients with high-grade bladder cancer to serve as a platform for therapeutic drug discovery. Patients and MethodsAn integrative analysis of 97 high-grade bladder tumors was conducted to identify actionable drug targets, which are defined as genomic alterations that have been clinically validated in another cancer type (eg, BRAF mutation) or alterations for which a selective inhibitor of the target or pathway is under clinical investigation. DNA copy number alterations (CNAs) were defined by using array comparative genomic hybridization. Mutation profiling was performed by using both mass spectroscopy-based genotyping and Sanger sequencing. ResultsSixty-one percent of tumors harbored potentially actionable genomic alterations. A core pathway analysis of the integrated data set revealed a nonoverlapping pattern of mutations in the RTK-RAS-RAF and phosphoinositide 3-kinase/AKT/mammalian target of rapamycin pathways and regulators of G 1 -S cell cycle progression. Unsupervised clustering of CNAs defined two distinct classes of bladder tumors that differed in the degree of their CNA burden. Integration of mutation and copy number analyses revealed that mutations in TP53 and RB1 were significantly more common in tumors with a high CNA burden (P Ͻ .001 and P Ͻ .003, respectively). ConclusionHigh-grade bladder cancer possesses substantial genomic heterogeneity. The majority of tumors harbor potentially tractable genomic alterations that may predict for response to target-selective agents. Given the genomic diversity of bladder cancers, optimal development of target-specific agents will require pretreatment genomic characterization.

It appears that PBL are heterogenous in terms of clinical presentation and morphology. The outcome presented here is superior to that originally reported.

Context.— Fine-needle aspiration of thyroid nodules is a reliable diagnostic method to determine the nature of thyroid nodules. Nonetheless, indeterminate cytology diagnoses remain a diagnostic challenge. The development of multiplex molecular techniques and the identification of genetic alterations associated with different follicular cell–derived cancers in the thyroid have led to the introduction of several commercially available tests. Objective.— To summarize the most common commercially available molecular testing in thyroid cancer, focusing on the technical features and test performance validation. Data Sources.— Peer-reviewed original articles, review articles, and published conference abstracts were reviewed to analyze the advantages and limitations of the most common tests used in the evaluation of thyroid needle aspirations. Conclusions.— The most common tests available include the Afirma Gene Expression Classifier, ThyGenX, and ThyroSeq. The excellent negative predictive value (NPV) of the Afirma test allows it to be used as a “rule out” test. ThyGenX analyzes a panel of DNA mutations and RNA translocation fusion markers to assess the risk of malignancy with good NPV and positive predictive value. ThyroSeq is a next-generation sequencing–based gene mutation and fusion test that has been reported to have the best NPV and positive predictive value combined, suggesting that it can be used as a “rule in” and “rule out” test. Molecular testing of cytology specimens from thyroid nodules has the potential to play a major role in the evaluation of indeterminate thyroid lesions.

Background The Afirma gene expression classifier (GEC) is used to assess malignancy risk in indeterminate thyroid nodules (ITNs) classified as Bethesda category III/IV. Our objective was to analyze GEC performance at two institutions with high thyroid cytopathology volumes but differing prevalence of malignancy. Methods Retrospective analysis of all ITNs evaluated with the GEC at Memorial Sloan Kettering Cancer Center (MSK; n = 94) and Mount Sinai Beth Israel (MSBI; n = 71). These institutions have differing prevalences of malignancy in ITNs: 30–38 % (MSK) and 10–19 % (MSBI). Surgical pathology was correlated with GEC findings for each matched nodule. Performance characteristics were estimated using Bayes Theorem. Results Patient and nodule characteristics were similar at MSK and MSBI. The GEC-benign call rates were 38.3 % (MSK) and 52.1 % (MSBI). Of the GEC-benign nodules, 8.3 % (MSK) and 13.5 % (MSBI) were treated surgically. Surgical pathology indicated that all of GEC-benign nodules were benign. Of the GEC-suspicious nodules, 60.0 % (MSK) and 61.7 % (MSBI) underwent surgery. Positive predictive values (PPVs) for GEC-suspicious results were 57.1 % (95 % CI 41.0–72.3) at MSK and 14.3 % (95 % CI 0.2–30.2) at MSBI. The estimated negative predictive values (NPVs) were 86–92 % at MSK and 95–98 % at MSBI. Conclusions There were wide variations in the Afirma GEC-benign call rate, PPV, and NPV between MSBI (a comprehensive health system) and MSK (a tertiary referral cancer center), which had differing rates of malignancy in ITNs. The GEC could not routinely alter management in either institution. We believe that this assay would be expected to be most informative in practice settings where the prevalence of malignancy is 15–21 %, such that NPV >95 % and PPV >25 % would be anticipated. Knowing the prevalence of malignancy in ITNs at a particular institution is critical for reliable interpretation of GEC results.