Validation of PRKCB Immunohistochemistry as a Biomarker for the Diagnosis of Ewing Sarcoma.

Background: Ewing sarcoma (ES) can be confirmed by identifying the EWSR1-FLI1 fusion transcript. This study is to investigate whether immunostaining (IHC) of PRKCB-a protein directly regulated by EWSR1-FLI1 is a surrogate maker for diagnosing ES in routine practice. Methods: Microarray gene expression analyses were conducted. RKCB IHC was applied to 69 ES confirmed by morphology and molecular methods, and 41 non-Ewing small round cell tumors. EWSR1 rearrangement, EWSR1-FLI1 fusion or t(11;22)(q24;q12) were identified by fluorescence in situ hybridization, reverse transcriptase polymerase chain reaction, or cytogenetic analysis, respectively. Results: Gene array analyses showed significant overexpression of the PRKCB in ES. PRKCB IHC was positive in 19 cases of ES with EWSR1-FLI1 fusion, 3 cases with cytogenetic 11:22 translocation and 59 cases with EWSR1 rearrangement while negative in only one EWSR1 rearranged case. PRKCB IHC is sensitive (98%) and specific (96%) in detecting EWSR1 rearranged ES. Conclusions: PRKCB is a reliable antibody for diagnosing ES in routine practice.

A phase I/randomized phase II study of GM.CD40L vaccine in combination with CCL21 in patients with advanced lung adenocarcinoma.

The GM.CD40L vaccine, which recruits and activates dendritic cells, migrates to lymph nodes, activating T cells and leading to systemic tumor cell killing. When combined with the CCL21 chemokine, which recruits T cells and enhances T-cell responses, additive effects have been demonstrated in non-small cell lung cancer mouse models. Here, we compared GM.CD40L versus GM.CD40L plus CCL21 (GM.CD40L.CCL21) in lung adenocarcinoma patients with ≥ 1 line of treatment. In this phase I/II randomized trial (NCT01433172), patients received intradermal vaccines every 14 days (3 doses) and then monthly (3 doses). A two-stage minimax design was used. During phase I, no dose-limiting toxicities were shown in three patients who received GM.CD40L.CCL21. During phase II, of evaluable patients, 5/33 patients (15.2%) randomized for GM.DCD40L (p = .023) and 3/32 patients (9.4%) randomized for GM.DCD40L.CCL21 (p = .20) showed 6-month progression-free survival. Median overall survival was 9.3 versus 9.5 months with GM.DCD40L versus GM.DCD40L.CCL21 (95% CI 0.70-2.25; p = .44). For GM.CD40L versus GM.CD40L.CCL21, the most common treatment-related adverse events (TRAEs) were grade 1/2 injection site reaction (51.4% versus 61.1%) and grade 1/2 fatigue (35.1% versus 47.2%). Grade 1 immune-mediated TRAEs were isolated to skin. No patients showed evidence of pseudo-progression or immune-related TRAEs of grade 1 or greater of pneumonitis, endocrinopathy, or colitis, and none discontinued treatment due to toxicity. Although we found no significant associations between vaccine immunogenicity and outcomes, in limited biopsies, one patient treated with GMCD40L.CCL21 displayed abundant tumor-infiltrating lymphocytes. This possible effectiveness warrants further investigation of GM.CD40L in combination approaches.

Advances in EGFR as a Predictive Marker in Lung Adenocarcinoma.

BACKGROUND: Worldwide, lung cancer is the most common cause of mortality. Toxins from tobacco smoke are known to increase the risk of lung cancer; however, up to 15% of lung cancer-related deaths in men and up to 50% of lung cancer-related deaths in women occur in people who do not smoke. Despite the fact that chemotherapy generally provides a survival benefit for non-small-cell lung cancer, not every patient will respond to therapy and many experience therapy-related adverse events. Thus, predictive markers are used to determine which patients are more likely to respond to a given regimen. METHODS: We reviewed the current medical literature in English relating to predictive markers that may be positive, such as the presence of an activating EGFR mutation. RESULTS: The advances in using EGFR as a molecular predictive marker were summarized. This biomarker influences therapeutic response in patients with lung adenocarcinoma. Clinical evidence supporting its value is also reviewed. CONCLUSIONS: The use of EGFR as a predictive factor in lung adenocarcinoma may help target therapy to individual tumors to achieve the best likelihood for long-term survival and to avoid adverse events from medications unlikely to be effective.

Special Technologies for Ex Vivo Analysis of Cancer.

BACKGROUND: Predictive assays for cancer treatment are not new technology, but they have failed to meet the criteria necessary for standardized use in clinical decision-making. METHODS: The authors summarize the use of predictive assays and the challenges and values associated with these assays in the clinical setting. RESULTS: Predictive assays commercially available in the clinical setting are not standardized, have significant obstacles to overcome, and cannot be relied upon by health care professionals due to the limited value these assays provide to the decision-making process for the treatment of patients. CONCLUSIONS: A method that more closely recapitulates the human tumor microenvironment and accurately predicts response with high reproducibility would be beneficial to patient outcomes and quality of life.

A miniaturized chemical proteomic approach for target profiling of clinical kinase inhibitors in tumor biopsies.

While targeted therapy based on the idea of attenuating the activity of a preselected, therapeutically relevant protein has become one of the major trends in modern cancer therapy, no truly specific targeted drug has been developed and most clinical agents have displayed a degree of polypharmacology. Therefore, the specificity of anticancer therapeutics has emerged as a highly important but severely underestimated issue. Chemical proteomics is a powerful technique combining postgenomic drug-affinity chromatography with high-end mass spectrometry analysis and bioinformatic data processing to assemble a target profile of a desired therapeutic molecule. Due to high demands on the starting material, however, chemical proteomic studies have been mostly limited to cancer cell lines. Herein, we report a down-scaling of the technique to enable the analysis of very low abundance samples, as those obtained from needle biopsies. By a systematic investigation of several important parameters in pull-downs with the multikinase inhibitor bosutinib, the standard experimental protocol was optimized to 100 µg protein input. At this level, more than 30 well-known targets were detected per single pull-down replicate with high reproducibility. Moreover, as presented by the comprehensive target profile obtained from miniaturized pull-downs with another clinical drug, dasatinib, the optimized protocol seems to be extendable to other drugs of interest. Sixty distinct human and murine targets were finally identified for bosutinib and dasatinib in chemical proteomic experiments utilizing core needle biopsy samples from xenotransplants derived from patient tumor tissue. Altogether, the developed methodology proves robust and generic and holds many promises for the field of personalized health care.

Phase 2 randomized study of enzastaurin (LY317615) for lung cancer prevention in former smokers.

BACKGROUND: Chemoprevention for lung cancer with nutraceutical or anti-inflammatory agents has had mixed clinical benefit. Novel targeted agents hold the promise of greater efficacy and selectivity. The authors of this report evaluated enzastaurin, a selective protein kinase C-ß (PKC-ß) inhibitor with antiproliferative and proapoptotic properties, in former smokers. METHODS: The primary objective of this study was to compare the average fraction of Ki-67-stained cells (the Ki-67 labeling index [LI]) in bronchial biopsy specimens that were collected before and after treatment. Participants were randomized (2:1) to receive either 6 months of daily oral enzastaurin (500 mg) or placebo. Stratification was based on morphology, history of lung cancer, and airway obstruction. RESULTS: In pretrial investigations, the rationale for PKC-ß inhibition and pathway interrogation was established in premalignant lesions and early stage lung cancer. In an intent-to-treat analysis, of 40 randomized participants, there was no significant difference in the pretreatment/post-treatment change in the Ki-67 LI between the enzastaurin group and the placebo group (P = .53). Six participants discontinued enzastaurin, including 4 participants who had adverse events, including abdominal distension, deep vein thrombosis, hyponatremia, and rash, and 2 participants who decided to discontinue. One participant in the placebo group was discontinued on the study because of noncompliance. Two participants had ≥1 serious adverse event (bradycardia, deep vein thrombosis, and hypotension). CONCLUSIONS: To the authors' knowledge, this represents the first chemoprevention trial with a non-US Food and Drug Administration-approved, oral, small-molecule-targeted agent. Although the primary endpoint was not met, enzastaurin was tolerable for 6 months by 75% of participants, and there was a suggestion of response in a subset analysis that was restricted to those who had metaplastic or dysplastic lesions.

EGFR/Src/Akt signaling modulates Sox2 expression and self-renewal of stem-like side-population cells in non-small cell lung cancer.

BACKGROUND: Cancer stem cells are thought to be responsible for the initiation and progression of cancers. In non-small cell lung cancers (NSCLCs), Hoechst 33342 dye effluxing side population (SP) cells are shown to have stem cell like properties. The oncogenic capacity of cancer stem-like cells is in part due to their ability to self-renew; however the mechanistic correlation between oncogenic pathways and self-renewal of cancer stem-like cells has remained elusive. Here we characterized the SP cells at the molecular level and evaluated its ability to generate tumors at the orthotopic site in the lung microenvironment. Further, we investigated if the self-renewal of SP cells is dependent on EGFR mediated signaling. RESULTS: SP cells were detected and isolated from multiple NSCLC cell lines (H1650, H1975, A549), as well as primary human tumor explants grown in nude mice. SP cells demonstrated stem-like properties including ability to self-renew and grow as spheres; they were able to generate primary and metastatic tumors upon orthotopic implantation into the lung of SCID mice. In vitro study revealed elevated expression of stem cell associated markers like Oct4, Sox2 and Nanog as well as demonstrated intrinsic epithelial to mesenchymal transition features in SP cells. Further, we show that abrogation of EGFR, Src and Akt signaling through pharmacological or genetic inhibitors suppresses the self-renewal growth and expansion of SP-cells and resulted in specific downregulation of Sox2 protein expression. siRNA mediated depletion of Sox2 significantly blocked the SP phenotype as well as its self-renewal capacity; whereas other transcription factors like Oct4 and Nanog played a relatively lesser role in regulating self-renewal. Interestingly, Sox2 was elevated in metastatic foci of human NSCLC samples. CONCLUSIONS: Our findings suggest that Sox2 is a novel target of EGFR-Src-Akt signaling in NSCLCs that modulates self-renewal and expansion of stem-like cells from NSCLC. Therefore, the outcome of the EGFR-Src-Akt targeted therapy may rely upon the expression and function of Sox2 within the NSCLC-CSCs.

Mass spectrometry mapping of epidermal growth factor receptor phosphorylation related to oncogenic mutations and tyrosine kinase inhibitor sensitivity.

The epidermal growth factor receptor (EGFR) plays an important role in cancer by activating downstream signals important in growth and survival. Inhibitors of EGFR are frequently selected as treatment for cancer including lung cancer. We performed an unbiased and comprehensive search for EGFR phosphorylation events related to somatic activating mutations and EGFR inhibitor (erlotinib) sensitivity. EGFR immunoprecipitation combined with high resolution liquid chromatography-mass spectrometry and label free quantitation characterized EGFR phosphorylation. Thirty (30) phosphorylation sites were identified including 12 tyrosine (pY), 12 serine (pS), and 6 threonine (pT). Site-specific phosphorylation was monitored by comparing ion signals from the corresponding unmodified peptide. Phosphorylation sites related to activating mutations in EGFR as well as sensitivity to erlotinib were identified using 31 lung cancer cell lines. We identified three sites (pY1092, pY1110, pY1172) correlated with activating mutations and three sites (pY1110, pY1172, pY1197) correlated with erlotinib sensitivity. Five sites (pT693, pY1092, pY1110, pY1172, and pY1197) were inhibited by erlotinib in concentration-dependent manner. Erlotinib sensitivity was confirmed using liquid chromatography coupled to multiple reaction monitoring (LC-MRM) and quantitative Western blotting. This LC-MS/MS strategy can quantitatively assess site-specific EGFR phosphorylation and can identify relationships between somatic mutations or drug sensitivity and protein phosphorylation.

Metastatic soft tissue sarcoma chemotherapy: an opportunity for personalized medicine.

BACKGROUND: Soft tissue sarcoma (STS) includes biologically and histologically diverse mesenchymal tumors that are relatively chemotherapy-resistant compared with other sarcoma subtypes. METHODS: The authors discuss the clinical challenges frequently encountered by medical oncologists and review the literature for predictive strategies to systematically approach chemotherapy decision making. RESULTS: There are no clinically validated predictive tests for chemotherapeutic response or resistance in STS. Clinical features including histology, stage, and patient age are currently used to guide therapy decisions in STS. CONCLUSIONS: A method to predict response or resistance to chemotherapy, utilizing both targeted and conventional agents, would be beneficial in reducing toxicity and improving response rates for patients with STS and also in designing clinical trials for this disease.

MUC1 is a downstream target of STAT3 and regulates lung cancer cell survival and invasion.

Signal transducer and activator of transcription 3 (STAT3) is aberrantly activated in human cancer including lung cancer and has been implicated in transformation, tumorigenicity, and metastasis. One putative downstream gene regulated by Stat3 is MUC1 which also has important roles in tumorigenesis. We determined if Stat3 regulates MUC1 in lung cancer cell lines and what function MUC1 plays in lung cancer cell biology. We examined MUC1 expression in non-small cell lung cancer (NSCLC) cell lines and found high levels of MUC1 protein expression associated with higher levels of tyrosine phosphorylated STAT3. STAT3 knockdown downregulated MUC1 expression whereas constitutive STAT3 expression increased MUC1 expression at mRNA and protein levels. MUC1 knockdown induced cellular apoptosis concomitant with reduced Bcl-XL and sensitized cells to cisplatin treatment. MUC1 knockdown inhibited tumor growth and metastasis in an orthotopic mouse model of lung cancer by activating apoptosis and inhibiting cell proliferation in vivo. These results demonstrate that constitutively activated STAT3 regulates expression of MUC1, which mediates lung cancer cell survival and metastasis in vitro and in vivo. MUC1 appears to be a cooperating oncoprotein with multiple oncogenic tyrosine kinase pathways and could be an effective target for the treatment of lung cancer.

Optimizing the development of targeted agents in pancreatic cancer: tumor fine-needle aspiration biopsy as a platform for novel prospective ex vivo drug sensitivity assays.

At the present time, the optimal development of molecularly targeted anticancer agents is limited by the lack of clinically applicable tools to predict drug effects. This study aimed to develop methods that might be useful in predicting the efficacy of targeted agents in a novel model system of human pancreatic cancer. A series of xenografts were established in nude mice by implanting human pancreatic cancer tissue surgically resected from cancer patients. Animals were treated with the epidermal growth factor receptor inhibitor erlotinib, the mammalian target of rapamycin inhibitor temsirolimus, or vehicle. Tumor cells were sampled by fine-needle aspiration biopsy (FNAB) before (baseline, day 0) and at the completion of 28 days of treatment. Cells obtained at baseline were exposed to erlotinib or temsirolimus in short-term cell culture conditions (ex vivo). Western blot analysis was done to determine the degree of inhibition in the phosphorylation of extracellular signal-regulated kinase 1/2 and S6-ribosomal protein (downstream effectors of epidermal growth factor receptor and mammalian target of rapamycin, respectively) ex vivo and in vivo. Five of six xenografted tumors responded to temsirolimus, whereas only one tumor responded to erlotinib. The results of the ex vivo studies correctly predicted the pharmacodynamic effect of the agents in vivo as well as their gross antitumor effects. Finally, we showed the clinical feasibility of this approach, performing ex vivo assessment of drug-target response in FNAB samples from three patients with pancreatic cancer. Cancer cells obtained by FNAB, an established minimally invasive diagnostic procedure, can be used to test ex vivo the effects of targeted anticancer agents. These effects correlate with antitumor activity in vivo and may therefore provide an important tool applicable to clinical trials. Ultimately, an approach of this nature may facilitate the further refinement of patient selection in favor of individuals with molecular profiles, predicting a greater likelihood of therapeutic benefit.

An in vivo platform for translational drug development in pancreatic cancer.

Effective development of targeted anticancer agents includes the definition of the optimal biological dose and biomarkers of drug activity. Currently available preclinical models are not optimal to this end. We aimed at generating a model for translational drug development using pancreatic cancer as a prototype. Resected pancreatic cancers from 14 patients were xenografted and expanded in successive groups of nude mice to develop cohorts of tumor-bearing mice suitable for drug therapy in simulated early clinical trials. The xenografted tumors maintain their fundamental genotypic features despite serial passages and recapitulate the genetic heterogeneity of pancreatic cancer. The in vivo platform is useful for integrating drug screening with biomarker discovery. Passages of tumors in successive cohorts of mice do not change their susceptibility to anticancer agents and represent a perpetual live bank, facilitating the application of new technologies that will result in the creation of an integrated stable database of tumor-drug response data and biomarkers.

Assessment of gefitinib- and CI-1040-mediated changes in epidermal growth factor receptor signaling in HuCCT-1 human cholangiocarcinoma by serial fine needle aspiration.

One specific limitation to the clinical development of targeted cancer therapeutics is the lack of well-validated pharmacodynamic markers. Such tools might conceivably provide a framework within which to better evaluate the selection of specific molecules as therapeutic targets. Nevertheless, the practical application of this hypothesis in clinical development remains elusive. In this study, we present a minimally invasive pharmacodynamic assay for monitoring therapy-mediated changes in the activity of target signaling pathways by using fine needle aspiration (FNA) samples and quantitative ELISA methods. To this end, we used the HuCCT-1 cholangiocarcinoma cell line treated with gefitinib (ZD1839, Iressa), a selective blocker of the epidermal growth factor receptor (EGFR), and CI-1040, a selective inhibitor of the mitogen extracellular regulated kinase [mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase 1/2]. HuCCT-1 cells were resistant to gefitinib and CI-1040 alone but susceptible to the combination of these drugs in vitro and in vivo. This effect was associated with a greater inhibition of ERK1/2 activation, a downstream mediator in the EGFR-mitogen-activated protein/ERK kinase pathway. Using this model, we sought to assess whether FNA-obtained tumor biopsies could be used to measure signaling pathway activation. Cellular extracts prepared from FNA samples yielded adequately cellular, high-quality samples to assess therapy-mediated changes in EGFR and ERK1/2 phosphorylation by Western blotting and quantitative ELISA assays. Treatment with gefitinib alone effectively inhibited EGFR activation but failed to block ERK1/2 phosphorylation and tumor growth. Blocking was achieved by the addition of CI-1040 to the treatment regimen. These results show that the combination of serial FNA sampling with highly sensitive quantitative ELISA assays permits assessment of therapy-mediated changes in signaling pathways, which correlate well with antitumor effects. This assay is simple to implement and broadly applicable to diverse tumor types in clinical studies with cancer patients and may be useful in the development of targeted anticancer agents.

Microfluidic Biopsy Trapping Device for the Real-Time Monitoring of Tumor Microenvironment.

The tumor microenvironment is composed of cellular and stromal components such as tumor cells, mesenchymal cells, immune cells, cancer associated fibroblasts and the supporting extracellular matrix. The tumor microenvironment provides crucial support for growth and progression of tumor cells and affects tumor response to therapeutic interventions. To better understand tumor biology and to develop effective cancer therapeutic agents it is important to develop preclinical platforms that can faithfully recapitulate the tumor microenvironment and the complex interaction between the tumor and its surrounding stromal elements. Drug studies performed in vitro with conventional two-dimensional cancer cell line models do not optimally represent clinical drug response as they lack true tumor heterogeneity and are often performed in static culture conditions lacking stromal tumor components that significantly influence the metabolic activity and proliferation of cells. Recent microfluidic approaches aim to overcome such obstacles with the use of cell lines derived in artificial three-dimensional supportive gels or micro-chambers. However, absence of a true tumor microenvironment and full interstitial flow, leads to less than optimal evaluation of tumor response to drug treatment. Here we report a continuous perfusion microfluidic device coupled with microscopy and image analysis for the assessment of drug effects on intact fresh tumor tissue. We have demonstrated that fine needle aspirate biopsies obtained from patient-derived xenograft models of adenocarcinoma of the lung can successfully be analyzed for their response to ex vivo drug treatment within this biopsy trapping microfluidic device, wherein a protein kinase C inhibitor, staurosporine, was used to assess tumor cell death as a proof of principle. This approach has the potential to study tumor tissue within its intact microenvironment to better understand tumor response to drug treatments and eventually to choose the most effective drug and drug combination for individual patients in a cost effective and timely manner.

Identification of Synergistic, Clinically Achievable, Combination Therapies for Osteosarcoma.

Systemic therapy has improved osteosarcoma event-free and overall survival, but 30-50% of patients originally diagnosed will have progressive or recurrent disease, which is difficult to cure. Osteosarcoma has a complex karyotype, with loss of p53 in the vast majority of cases and an absence of recurrent, targetable pathways. In this study, we explored 54 agents that are clinically approved for other oncologic indications, agents in active clinical development, and others with promising preclinical data in osteosarcoma at clinically achievable concentrations in 5 osteosarcoma cell lines. We found significant single-agent activity of multiple agents and tested 10 drugs in all permutations of two-drug combinations to define synergistic combinations by Chou and Talalay analysis. We then evaluated order of addition to choose the combinations that may be best to translate to the clinic. We conclude that the repurposing of chemotherapeutics in osteosarcoma by using an in vitro system may define novel drug combinations with significant in vivo activity. In particular, combinations of proteasome inhibitors with histone deacetylase inhibitors and ixabepilone and MK1775 demonstrated excellent activity in our assays.

Annotation of human cancers with EGFR signaling-associated protein complexes using proximity ligation assays.

Strategies to measure functional signaling-associated protein complexes have the potential to augment current molecular biomarker assays, such as genotyping and expression profiling, used to annotate diseases. Aberrant activation of epidermal growth factor receptor (EGFR) signaling contributes to diverse cancers. We used a proximity ligation assay (PLA) to detect EGFR in a complex with growth factor receptor-bound protein 2 (GRB2), the major signaling adaptor for EGFR. We used multiple lung cancer cell lines to develop and characterize EGFR:GRB2 PLA and correlated this assay with established biochemical measures of EGFR signaling. In a panel of patient-derived xenografts in mice, the intensity of EGFR:GRB2 PLA correlated with the reduction in tumor size in response to the EGFR inhibitor cetuximab. In tumor biopsies from three cohorts of lung cancer patients, positive EGFR:GRB2 PLA was observed in patients with and without EGFR mutations, and the intensity of EGFR:GRB2 PLA was predictive of overall survival in an EGFR inhibitor-treated cohort. Thus, we established the feasibility of using PLA to measure EGFR signaling-associated protein complexes in patient-based materials, suggesting the potential for similar assays for a broader array of receptor tyrosine kinases and other key signaling molecules.

Molecular markers in cervical cytology.

It is expected that in the near future, the high sensitivity of array-based technologies and identification of panels of molecular fingerprints that are specific for each disease process will allow the pathologist to analyze cytologic samples and tissue biopsies by these technologies in conjunction with morphologic evaluation. This approach could lead to a new era in diagnosis and patient management, where each patient may receive individualized treatment according to the molecular characteristics of the disease that are obtained from a minute amount of tissue. Therefore, it is important for pathologists and other clinical specialists to have an understanding of these molecular technologies. It is hoped that this article will allow practitioners to incorporate these concepts into their training, and, eventually, into their daily practice.

Antitumor efficacy of the anti-interleukin-6 (IL-6) antibody siltuximab in mouse xenograft models of lung cancer.

INTRODUCTION: Interleukin-6 (IL-6) can activate downstream signaling pathways in lung cancer cells, such as the STAT3 pathway, and is reported to be produced by tumor cells with activating EGFR mutations. We examined IL-6/STAT3 in lung cancer tumor tissues and the effects of siltuximab, a neutralizing antibody to human IL-6, in mouse models of lung cancer. METHODS: IL-6 and STAT3 activation levels were compared with tumor histology and presence of KRAS mutations in snap-frozen, non-small-cell lung cancer tumors. The effects of siltuximab alone or in combination with erlotinib were examined in mouse xenograft models constructed using three cell line xenograft models and one primary explant mouse model. We examined the influence of cancer-associated fibroblasts (CAFs) on tumor growth and siltuximab effects. RESULTS: IL-6 levels were higher in tumors of squamous cell versus adenocarcinoma histology and were not associated with presence of KRAS mutations. Tyrosine phosphorylation status of STAT3 did not correlate with tumor IL-6 levels. Serine phosphorylation of STAT3 was correlated with KRAS mutation status. Both tumor and stromal cells contributed to total IL-6 within tumors. Siltuximab had minimal effect as a single agent in xenografts with tumor cells alone; however, in models coadministered with CAFs, siltuximab had more potent effects on tumor inhibition. We observed no effects of combined erlotinib and siltuximab. CONCLUSIONS: IL-6 is elevated in subsets of human NSCLCs, especially with squamous cell histology. Tumors supported by stromal production of IL-6 seem to be the most vulnerable to tumor growth inhibition by siltuximab.

A phase I, pharmacokinetic, and pharmacodynamic study of panobinostat, an HDAC inhibitor, combined with erlotinib in patients with advanced aerodigestive tract tumors.

PURPOSE: Panobinostat, a histone deacetylase (HDAC) inhibitor, enhances antiproliferative activity in non-small cell lung cancer (NSCLC) cell lines when combined with erlotinib. We evaluated this combination in patients with advanced NSCLC and head and neck cancer. EXPERIMENTAL DESIGN: Eligible patients were enrolled in a 3+3 dose-escalation design to determine the maximum tolerated dose (MTD) of twice weekly panobinostat plus daily erlotinib at four planned dose levels (DL). Pharmacokinetics, blood, fat pad biopsies (FPB) for histone acetylation, and paired pre and posttherapy tumor biopsies for checkpoint kinase 1 (CHK1) expression were assessed. RESULTS: Of 42 enrolled patients, 33 were evaluable for efficacy. Dose-limiting toxicities were prolonged-QTc and nausea at DL3. Adverse events included fatigue and nausea (grades 1-3), and rash and anorexia (grades 1-2). Disease control rates were 54% for NSCLC (n = 26) and 43% for head and neck cancer (n = 7). Of 7 patients with NSCLC with EGF receptor (EGFR) mutations, 3 had partial response, 3 had stable disease, and 1 progressed. For EGFR-mutant versus EGFR wild-type patients, progression-free survival (PFS) was 4.7 versus 1.9 months (P = 0.43) and overall survival was 41 (estimated) versus 5.2 months (P = 0.39). Erlotinib pharmacokinetics was not significantly affected. Correlative studies confirmed panobinostat's pharmacodynamic effect in blood, FPB, and tumor samples. Low CHK1 expression levels correlated with PFS (P = 0.006) and response (P = 0.02). CONCLUSIONS: We determined MTD at 30 mg (panobinostat) and 100 mg (erlotinib). Further studies are needed to further explore the benefits of HDAC inhibitors in patients with EGFR-mutant NSCLC, investigate FPB as a potential surrogate source for biomarker investigations, and validate CHK1's predictive role.

Squamous cell carcinoma with rhabdoid phenotype of skin/soft tissue in a transplant patient: an exceptional case and review of the literature.

Squamous cell carcinoma with rhabdoid features (SCCRF) is a very rare and unusual cutaneous tumor. Here, we report an extraordinary case diagnosed by fine needle aspiration biopsy, in a 66-year-old man, status post multiple organ transplantation. The patient presented with a large ulcerating fungating mass in his forearm that had all the light microscopic and immunohistochemical features of a SCCRF. Previously six cases of SCCRF phenotype diagnosed by surgical pathology have been reported. This is the first case diagnosed cytologically. A review of the literature with emphasis on the differential diagnoses of such unusual rhabdoid-like tumors in fine-needle aspiration biopsy and the potential molecular mechanism for rhabdoid phenotype in transplant patients are discussed.