Implementation of a Molecular Tumor Board: The Impact on Treatment Decisions for 35 Patients Evaluated at Dartmouth-Hitchcock Medical Center.

BACKGROUND: Although genetic profiling of tumors is a potentially powerful tool to predict drug sensitivity and resistance, its routine use has been limited because clinicians are often unfamiliar with interpretation and incorporation of the information into practice. We established a Molecular Tumor Board (MTB) to interpret individual patients' tumor genetic profiles and provide treatment recommendations. PATIENTS AND METHODS: DNA from tumor specimens was sequenced in a Clinical Laboratory Improvement Amendments-certified laboratory to identify coding mutations in a 50-gene panel (n = 34) or a 255-gene panel (n = 1). Cases were evaluated by a multidisciplinary MTB that included pathologists, oncologists, hematologists, basic scientists, and genetic counselors. RESULTS: During the first year, 35 cases were evaluated by the MTB, with 32 presented for recommendations on targeted therapies, and 3 referred for potential germline mutations. In 56.3% of cases, MTB recommended treatment with a targeted agent based on evaluation of tumor genetic profile and treatment history. Four patients (12.5%) were subsequently treated with a MTB-recommended targeted therapy; 3 of the 4 patients remain on therapy, 2 of whom experienced clinical benefit lasting >10 months. CONCLUSION: For the majority of cases evaluated, the MTB was able to provide treatment recommendations based on targetable genetic alterations. The most common reasons that MTB-recommended therapy was not administered stemmed from patient preferences and genetic profiling at either very early or very late stages of disease; lack of drug access was rarely encountered. Increasing awareness of molecular profiling and targeted therapies by both clinicians and patients will improve acceptance and adherence to treatments that could significantly improve outcomes. IMPLICATIONS FOR PRACTICE: Case evaluation by a multidisciplinary Molecular Tumor Board (MTB) is critical to benefit from individualized genetic data and maximize clinical impact. MTB recommendations shaped treatment options for the majority of cases evaluated. In the few patients treated with MTB-recommended therapy, disease outcomes were positive and support genetically informed treatment.

Effective capture of circulating tumor cells from a transgenic mouse lung cancer model using dendrimer surfaces immobilized with anti-EGFR.

The lack of an effective detection method for lung circulating tumor cells (CTCs) presents a substantial challenge to elucidate the value of CTCs as a diagnostic or prognostic indicator in lung cancer, particularly in nonsmall cell lung cancer (NSCLC). In this study, we prepared a capture surface exploiting strong multivalent binding mediated by poly(amidoamine) (PAMAM) dendrimers to capture CTCs originating from lung cancers. Given that 85% of the tumor cells from NSCLC patients overexpress epidermal growth factor receptor (EGFR), anti-EGFR was chosen as a capture agent. Following in vitro confirmation using the murine lung cancer cell lines (ED-1 and ED1-SC), cyclin E-overexpressing (CEO) transgenic mice were employed as an in vivo lung tumor model to assess specificity and sensitivity of the capture surface. The numbers of CTCs in blood from the CEO transgenic mice were significantly higher than those from the healthy controls (on average 75.3 ± 14.9 vs 4.4 ± 1.2 CTCs/100 µL of blood, p < 0.005), indicating the high sensitivity and specificity of our surface. Furthermore, we found that the capture surface also offers a simple, effective method for monitoring treatment responses, as observed by the significant decrease in the CTC numbers from the CEO mice upon a treatment using a novel anti-miR-31 locked nucleic acid (LNA), compared to a vehicle treatment and a control-LNA treatment (p < 0.05). This in vivo evaluation study confirms that our capture surface is highly efficient in detecting in vivo CTCs and thus has translational potential as a diagnostic and prognostic tool for lung cancer.

Breast MRI-detected cystic apocrine metaplasia: imaging features with microvessel analysis and histologic correlation.

OBJECTIVE: The purpose of this article is to characterize the histologic vascular features and distinguishing MRI features of cystic apocrine metaplasia to better understand imaging-pathology concordance. MATERIALS AND METHODS: Retrospective review of 261 consecutive MRI-guided biopsy cases was performed. Pathology results were reviewed for all biopsies; cystic apocrine metaplasia was identified as the predominant finding in 19 cases (7%). CD31 immunohistochemistry was subsequently performed on the most representative block of cystic apocrine metaplasia, and microvasculature was evaluated using computer-assisted image analysis. The contrast-enhanced MRI examinations correlating with the cystic apocrine metaplasia cases were independently reviewed by two radiologists specializing in breast imaging; lesions were analyzed for morphologic, kinetic, and T2 characteristics. RESULTS: On MRI review, 17 of 19 (89%) lesions were 10 mm or smaller. Washout kinetics were present in 11 of 19 (58%) lesions, and 14 of 19 (74%) lesions were at least partially hyperintense on T2-weighted sequences relative to adjacent glandular tissue. Cystic apocrine metaplasia had a higher percentage area (mean, 4.1%) of CD31-immunostained microvessels compared with background fibroglandular tissue (mean, 1.2%). CONCLUSION: Cystic apocrine metaplasia should be considered in the differential diagnosis of a T2-hyperintense enhancing focus or subcentimeter smoothly marginated mass, even if associated with washout kinetics. Cystic apocrine metaplasia contains a statistically significant increase in microvessel area compared with background fibroglandular tissue and fat and, therefore, may be considered a concordant result for this set of imaging findings.

Native MAG-1 antibody almost destroys human breast cancer xenografts.

A native form of mouse monoclonal IgG1 antibody called MAG-1, which recognizes an epitope on provasopressin, has been found to shrink and produce extensive necrosis of human breast tumor xenografts in nu/nu mice. We examined the ability of (90)Yttrium-labeled and native MAG-1 to affect the growth in nu/nu mice of cancer xenografts that were estrogen-responsive (from MCF-7 cells) and triple-negative (from MDA-MB231 cells). The growth rates of treated cells were compared to those receiving saline vehicle and those receiving (90)Yttrium-labeled and native forms of the ubiquitous antibody, MOPC21. Short-term treatments (4 doses over 6 days) not only with (90)Yttrium-MAG-1 but also native MAG-1 produced large reductions in size of rapidly growing tumors of both types, while both (90)Yttrium- MOPC21 and native MOPC21 had no effect. Native and (90)Yttrium-MAG-1 effects were similar, and arrested tumors recommenced growing soon after treatments stopped. Increasing native MAG-1 treatment to single dosing for 16 consecutive days shrank tumors of both types with no regrowth apparent over a 20-day post-treatment period of observation. Pathological examination of such tumors revealed they had undergone very extensive (>66%) necrosis.

Orthopaedic specimen preparation: what pathologists should know and do.

The purpose of this article is to stress the importance of imaging studies to the surgical pathologist when studying orthopaedic specimens and to emphasize specimen preparation, including sawing and decalcification techniques.

Breast cancer expresses functional NMDA receptors.

We demonstrate here that functional NMDAR1 and NMDAR2 receptors are expressed by Mcf-7 and SKBR3 breast cancer cell lines, and possibly by most or all high-grade breast tumors, and that these receptors are important for the growth of human breast cancer xenografts in mice. RT-PCR demonstrated mRNA for both NMDAR1 and NMDAR2 receptors are expressed in both Mcf-7 and SKBR3 cell lines, and these messages likely have sequences identical to those reported for human mRNAs. Proteins of the expected respective sizes 120 and 170 kD are generated from these mRNAs by the tumor cells. Cell growth was found to be significantly (P < 0.0001) impaired down to 10% of normal growth by the irreversible NMDAR1 antagonists MK-801 and memantine with IC 50s ranging from 600 to >800 microM and from 200 to 300 microM for the two lines. Paradoxically, memantine with a lower binding affinity had the greater influence of the two inhibitors on cell viability. Immunohistochemical examination of high-grade invasive ductal and lobular breast cancer with our polyclonal antibodies against a peptide (-Met-Ser-Ile-Tyr-Ser-Asp-Lys-Ser-Ile-His-) in the extracellular domain of the NMDAR1 receptor gave specific positive staining for the receptor in all 10 cases examined. Positive staining was chiefly concentrated at the membranes of these tumor tissues. No staining with these antibodies was found for normal breast and kidney tissues. When Mcf-7 cells were grown as tumor xenografts in nu/nu mice, the growth of these tumors was completely arrested by daily treatments with MK-801 over 5 days. All of these data point to active NMDAR receptors being expressed by most breast cancers, and having an important influence on their survival.

Central xanthoma of the jaw in association with Noonan syndrome.

Xanthomas are histiocytic lesions of the skin, soft tissue, and bone and are generally considered to be reactive in nature. When they arise in the bones of the jaw, they are referred to as central xanthomas. New evidence supports the hypothesis that central xanthomas are a separate and distinct entity from their extragnathic counterparts. Noonan syndrome (NS) is an autosomal dominant disorder that has been associated with giant cell lesions, which also commonly occur in the jaw. We present a case of a 15-year-old boy with NS who presented with a radiolucent lesion of the mandible that on excision was found to be a central xanthoma. Although giant cell lesions have been well described in NS, xanthomas of the jaw have not been reported. We will also discuss the entities that must be excluded before making a diagnosis of central xanthoma, as this can affect both treatment and follow-up.

Repression of cyclin D1 as a target for germ cell tumors.

Metastatic germ cell tumors (GCT) are curable, however GCTs refractory to cisplatin-based chemotherapy have a poor prognosis. This study explores D-type cyclins as molecular targets in GCTs because all-trans-retinoic acid (RA)-mediated differentiation of the human embryonal carcinoma (EC) cell line NT2/D1 is associated with G1 cell cycle arrest and proteasomal degradation of cyclin D1. RA effects on D-type cyclins are compared in human EC cells that are RA sensitive or dually RA and cisplatin resistant (NT2/D1-R1) and in clinical GCTs that have both EC and mature teratoma components. Notably, GCT differentiation was associated with reduced cyclin D1 but increased cyclin D3 expression. RA was shown here to repress cyclin D1 through a transcriptional mechanism in addition to causing its degradation. The siRNA-mediated repression of individual cyclin D species resulted in growth inhibition in both RA sensitive and resistant EC cells. Only repression of cyclin D1 occurred in vitro and when clinical GCTs mature, implicating cyclin D1 as a molecular therapeutic target. To confirm this, the EGFR-tyrosine kinase inhibitor, Erlotinib, was used to repress cyclin D1. This inhibited proliferation in RA and cisplatin sensitive and resistant EC cells. Taken together, these findings implicate cyclin D1 targeting agents for the treatment of GCTs.

Clinical Genotyping of Non-Small Cell Lung Cancers Using Targeted Next-Generation Sequencing: Utility of Identifying Rare and Co-mutations in Oncogenic Driver Genes.

Detection of somatic mutations in non-small cell lung cancers (NSCLCs), especially adenocarcinomas, is important for directing patient care when targeted therapy is available. Here, we present our experience with genotyping NSCLC using the Ion Torrent Personal Genome Machine (PGM) and the AmpliSeq Cancer Hotspot Panel v2. We tested 453 NSCLC samples from 407 individual patients using the 50 gene AmpliSeq Cancer Hotspot Panel v2 from May 2013 to July 2015. Using 10 ng of DNA, up to 11 samples were simultaneously sequenced on the Ion Torrent PGM (316 and 318 chips). We identified variants with the Ion Torrent Variant Caller Plugin, and Golden Helix's SVS software was used for annotation and prediction of the significance of the variants. Three hundred ninety-eight samples were successfully sequenced (12.1% failure rate). In all, 633 variants in 41 genes were detected with a median of 2 (range of 0 to 7) variants per sample. Mutations detected in BRAF, EGFR, ERBB2, KRAS, NRAS, and PIK3CA were considered potentially actionable and were identified in 237 samples, most commonly in KRAS (37.9%), EGFR (11.1%), BRAF (4.8%), and PIK3CA (4.3%). In our patient population, all mutations in EGFR, KRAS, and BRAF were mutually exclusive. The Ion Torrent Ampliseq technology can be utilized on small biopsy and cytology specimens, requires very little input DNA, and can be applied in clinical laboratories for genotyping of NSCLC. This targeted next-generation sequencing approach allows for detection of common and also rare mutations that are clinically actionable in multiple patients simultaneously.

Consequences of altered TGF-beta expression and responsiveness in breast cancer: evidence for autocrine and paracrine effects.

To characterize the impact of increased production of TGF-beta in a xenograft model of human breast cancer, TGF-beta-responsive MDA-231 cells were genetically modified by stable transfection so as to increase their production of active TGF-beta1. Compared with control cells, cells that produced increased amounts of TGF-beta proliferated in vitro more slowly. In vivo, however, tumors derived from these cells exhibited increased proliferation and grew at an accelerated pace. To evaluate the role of autocrine TGF-beta signaling, cells were also transfected with a dominant-negative truncated type II TGF-beta receptor (TbetaRII). Disruption of autocrine TGF-beta signaling in the TGF-beta-overexpressing cells reduced their in vivo growth rate. Co-inoculation of Matrigel with the TGF-beta-overexpressing cells expressing the truncated TbetaRII compensated for their diminished in vivo growth capacity, compared with the TGF-beta-overexpressing cells with an intact autocrine loop. Tissue invasion by the tumor was a distinctive feature of the TGF-beta-overexpressing cells, whether or not the autocrine loop was intact. Furthermore, tumors derived from TGF-beta-overexpressing cells, irrespective of the status of the autocrine TGF-beta-signaling pathway, had a higher incidence of lung metastasis. Consistent with the suggestion that TGF-beta's enhancement of invasion and metastasis is paracrine-based, we observed no significant differences among the cell clones in an in vitro invasion assay. Thus, in this experimental model system in vitro assays of cell proliferation and invasion do not accurately reflect in vivo observations, perhaps due to autocrine and paracrine effects of TGF-beta that influence the important in vivo-based phenomena of tumor growth, invasion, and metastasis.

Immunohistochemical detection of NRSA on small cell lung cancer with a monoclonal antibody (MAG-1) that recognizes the carboxyl terminus of provasopressin.

A single monoclonal antibody (MAG-1) directed against the C-terminal 18-amino acid region (VAGc18) of provasopressin was examined as an agent for recognizing the tumor-specific NRSA marker common to small cell lung cancer (SCLC) in formalin-fixed tissues with ABC immunohistochemistry. SCLC tumors were obtained from several tissue locations and included primary, metastatic, and recurrent disease. Positive staining was found in 91% of cases (53/58). All five of the unreactive tumors were of the lungs or chest wall, and there did not appear to be an association of this negativity with disease stage, age, or sex. Alternatively, almost all primary lesions, almost all metastatic lesions, and all recurrent lesions examined gave a positive reaction with MAG-1. For this study, vasopressin-producing cells of the human anterior hypothalamus served as a positive control, while negative controls comprised normal lung tissue, tumor that received MAG-1 in the presence of an excess of antigen (VAGc18 peptide), or tumor reacted with a commercial IgG1 isotype as primary antibody. All of the results indicate that MAG-1 can be effectively used to selectively identify the NRSA marker on almost all SCLC tumors, at all disease stages, and at all locations. Since all four tumors tested showing no reactivity with MAG-1 gave a positive reaction for synaptophysin, it is proposed that a combined use of MAG-1 with synaptophysin antibodies could allow all SCLC tumors to be detected by ABC immunohistochemistry.

Epidermal growth factor receptor tyrosine kinase inhibition represses cyclin D1 in aerodigestive tract cancers.

PURPOSE: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are active in cancer therapy. Mechanisms engaged during these clinical responses need to be determined. We reported previously that epidermal growth factor stimulation markedly increased cyclin D1 protein expression in human bronchial epithelial (HBE) cells, and this was opposed by chemoprevention with all-trans-retinoic acid. The current study sought to determine whether the EGFR TKI erlotinib repressed cyclin D1 protein expression in immortalized HBE cells, lung cancer cell lines, and clinical aerodigestive tract cancers. EXPERIMENTAL DESIGN: The BEAS-2B immortalized HBE cell line was exposed to varying concentrations of erlotinib, and effects on proliferation, cell cycle distribution, G1 cyclin expression, and cyclin D1 reporter activity were measured. Non-small-cell lung cancer cell lines were also evaluated for changes in proliferation and cyclin protein expression after erlotinib treatments. A proof of principle clinical trial was conducted. During this study, patients underwent a 9-day course of erlotinib treatment. Pretreatment and posttreatment tumor biopsies were obtained, and changes in candidate biomarkers were determined by immunostaining. Plasma pharmacokinetics and tumor tissue erlotinib concentrations were measured. RESULTS: Erlotinib, at clinically achievable dosages, repressed BEAS-2B cell growth, triggered G1 arrest, and preferentially reduced cyclin D1 protein expression and transcriptional activation. Erlotinib also preferentially repressed proliferation and cyclin D1 protein expression in responsive, but not resistant, non-small-cell lung cancer cell lines. This occurred in the presence of wild-type EGFR sequence at exons 18, 19, and 21. Five patients were enrolled onto an erlotinib proof of principle clinical trial, and four cases were evaluable. Pharmacokinetic studies established therapeutic erlotinib plasma levels in all patients, but tissue levels exceeding 2 micromol/L were detected in only two cases. Notably, these cases had pathological evidence of response (necrosis) in posttreatment biopsies as compared with pretreatment biopsies. In these cases, marked repression of cyclin D1 and the proliferation marker Ki-67 was detected by immunohistochemical assays. Cases without pathological response to erlotinib did not exhibit changes in cyclin D1 or Ki-67 immunohistochemical expression and had much lower erlotinib tissue levels than did responding cases. CONCLUSIONS: Taken together, these in vitro and in vivo findings provide direct evidence for repression of cyclin D1 protein as a surrogate marker of response in aerodigestive tract cancers to erlotinib treatment. These findings also provide a rationale for combining an EGFR TKI with an agent that would cooperatively repress cyclin D1 expression in clinical trials for aerodigestive tract cancer therapy or chemoprevention.

Targeting the neurophysin-related cell surface antigen on small cell lung cancer cells using a monoclonal antibody against the glycopeptide region (MAG-1) of provasopressin.

The vasopressin (VP) gene is largely expressed in hypothalamic neurons, where the resultant pro-VP protein is enzymatically cleaved into its peptide hormone components, which include the neuropeptide VP, VP-associated neurophysin, and VP-associated glycopeptide (VAG). Small cell lung cancer (SCLC) tumors also express the VP gene, but the tumor pro-VP protein can remain intact and localize to the cell surface membrane. Previous studies have shown that polyclonal antibodies directed against different regions of the pro-VP protein bind specifically to the surface of cultured SCLC cells and recognize proteins of approximately 20 and approximately 40 kDa in cultured SCLC whole-cell lysate. Thus, these proteins have been designated neurophysin-related cell surface antigen (NRSA). A monoclonal antibody (mAb) designated MAG-1 was raised in this laboratory using a synthetic peptide representing the COOH-terminal sequence of VAG. The MAG-1 mAb recognizes NRSA in SCLC cell and tissue lysates by Western analysis, whereas immunofluorescent cytometric and microscopic analyses indicate that MAG-1 reacts specifically with NRSA on the surface of viable SCLC cells of both the classical and the variant subtype. Immunohistochemical analysis demonstrates that MAG-1 reacts with human SCLC tumor, but not with normal pulmonary epithelial cells in lung tissue. Additionally, a MAG-1 Fab fragment was generated that was also able to recognize NRSA. This is the first study to demonstrate that a mAb directed to the VAG region of the pro-VP protein has the potential for development into an in vivo diagnostic and therapeutic tool that targets plasma membrane-incorporated NRSA.

Cell cycle and apoptosis regulatory proteins, proliferative markers, cell signaling molecules, CD209, and decorin immunoreactivity in low-grade myxofibrosarcoma and myxoma.

The histologic differential diagnosis between intramuscular myxoma and low-grade myxofibrosarcoma can be quite difficult in some cases. To identify a diagnostic immunohistochemical marker, we compared the staining profiles of 19 different antigens, including cell cycle proteins, apoptosis proteins, and proliferative markers, and selected other signaling and structural proteins in these two tumors. Ten cases each of intramuscular myxoma and low-grade myxofibrosarcoma were stained with antibodies directed against apoptosis regulatory proteins (Bcl2, activated caspase-3, phospho-H2A.X, and cleaved PARP), cell cycle regulatory proteins (Rb1, Cyclin-A, CDKN1B, and Cdt1), proliferative markers (KI67, MCM2, phospho-histone H3, and geminin), cell signalling molecules (c-Myc, EGF, EGFR, PLA2G4A, and HSP90), a dendritic cell marker (CD209), and the extracellular matrix proteoglycan decorin. Staining patterns of myxoma and myxofibrosarcoma were compared using Fisher's exact test and the Mann-Whitney test. For each potential diagnostic marker studied, the proportions of cases scored as positive on both dichotomous or ordinal scales were not significantly different between myxoma and myxofibrosarcoma. Myxoma and myxofibrosarcoma share a common immunophenotype for each of the markers studied. Distinction between these tumors is still predominantly based on morphologic criteria.

Small cell neuroendocrine carcinomas of the lung do not harbor high-risk human papillomavirus.

High-risk subtypes of the human papillomavirus (HPV) are known to drive the pathogenesis of cervical, anogenital, and oropharyngeal squamous cell carcinomas. Recent reports have shown that HPV is also associated with small cell neuroendocrine carcinomas of the cervix and oropharynx. Little is known about HPV as a driver of neuroendocrine tumors at other sites, in particular, small cell lung cancer (SCLC). The aim of this study was to evaluate SCLC for the presence of high-risk HPV to further elucidate the role of HPV in SCLC. Archived formalin-fixed, paraffin-embedded surgical resection specimens from 20 primary SCLC from 19 patients were identified from 2004 to 2013. Two cervical small cell carcinomas were included as controls. Small cell neuroendocrine phenotype was confirmed by review of morphology and prior immunohistochemistry staining. Immunohistochemistry for p16 (INK4a) expression was performed in all cases. DNA was extracted from formalin-fixed, paraffin-embedded specimens and run on the Roche Linear Array HPV Genotyping test and a real-time polymerase chain reaction HPV assay. Pathologic tumor stage was collected from surgical pathology reports. High-risk HPV genotypes were not detected in any of the 20 SCLC specimens, whereas p16 was up-regulated in 14 (70%) of 20. p16 up-regulation can be used as an indicator of disruption of the Rb pathway either by integration of the HPV E7 oncoprotein or other mechanisms. In conclusion, our findings indicate that, unlike some other small cell neuroendocrine carcinomas, the pathogenesis of SCLC does not appear to be associated with high-risk HPV infection, a potentially very useful characteristic when determining primary from metastatic tumors.

Impact of the 2013 ASCO/CAP HER2 Guideline Updates at an Academic Medical Center That Performs Primary HER2 FISH Testing: Increase in Equivocal Results and Utility of Reflex Immunohistochemistry.

OBJECTIVES: The 2013 American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guideline updates lowered the threshold for HER2 positivity and altered the equivocal category. The goal of this study was to evaluate the impact of these changes on the distribution of HER2 fluorescence in situ hybridization (FISH) status. The utility of reflex HER2 immunohistochemistry (IHC) for FISH equivocal cases was also examined. METHODS: We retrospectively reviewed all invasive breast cancers analyzed for HER2 via dual-probe FISH (PathVysion; Abbott Laboratories. Abbott Park, IL) 12 months before and after the HER2 guidelines updates were implemented. Reflex HER2 IHC results were recorded for HER2 FISH equivocal cases. RESULTS: There was a significant increase in the number of HER2 FISH equivocal results after the guideline updates (4.9% vs 1.4%, P = .0087) that was independent of specimen type (core vs surgical, P = .6). All 17 FISH equivocal cases after the updates had reflex HER2 IHC: two (12%) of 17 were positive, 12 (71%) of 17 remained equivocal, and three (18%) of 17 were negative. CONCLUSIONS: Implementation of the 2013 ASCO/CAP HER2 guideline updates resulted in an increase in HER2 FISH equivocal results, which can be attributed to HER2 copy number, regardless of the HER2/CEP17 ratio. Reflex IHC for FISH equivocal cases is of limited utility; however, IHC does assign HER2 positivity or negativity in a small percentage of cases.

CDK2 Inhibition Causes Anaphase Catastrophe in Lung Cancer through the Centrosomal Protein CP110.

Aneuploidy is frequently detected in human cancers and is implicated in carcinogenesis. Pharmacologic targeting of aneuploidy is an attractive therapeutic strategy, as this would preferentially eliminate malignant over normal cells. We previously discovered that CDK2 inhibition causes lung cancer cells with more than two centrosomes to undergo multipolar cell division leading to apoptosis, defined as anaphase catastrophe. Cells with activating KRAS mutations were especially sensitive to CDK2 inhibition. Mechanisms of CDK2-mediated anaphase catastrophe and how activated KRAS enhances this effect were investigated. Live-cell imaging provided direct evidence that following CDK2 inhibition, lung cancer cells develop multipolar anaphase and undergo multipolar cell division with the resulting progeny apoptotic. The siRNA-mediated repression of the CDK2 target and centrosome protein CP110 induced anaphase catastrophe of lung cancer cells. In contrast, CP110 overexpression antagonized CDK2 inhibitor-mediated anaphase catastrophe. Furthermore, activated KRAS mutations sensitized lung cancer cells to CDK2 inhibition by deregulating CP110 expression. Thus, CP110 is a critical mediator of CDK2 inhibition-driven anaphase catastrophe. Independent examination of murine and human paired normal-malignant lung tissues revealed marked upregulation of CP110 in malignant versus normal lung. Human lung cancers with KRAS mutations had significantly lower CP110 expression as compared with KRAS wild-type cancers. Thus, a direct link was found between CP110 and CDK2 inhibitor antineoplastic response. CP110 plays a mechanistic role in response of lung cancer cells to CDK2 inhibition, especially in the presence of activated KRAS mutations.

A novel Streptococcus organism identified in a case of fulminant endocarditis using 16S rDNA sequencing.

We report the identification of a virulent Streptococcus organism associated with fulminant endocarditis, using 16S rRNA gene amplification, sequencing and assembly from formalin-fixed, paraffin-embedded archival heart valve tissue, years after the autopsy of a patient.

Immunohistochemical evaluation of vasopressin expression in breast fibrocystic disease and ductal carcinoma in situ (DCIS).

We previously found that expression of the vasopressin gene is a common feature of human breast cancer. In the present study we first examined 21 different cases of benign fibrocystic breast disease for vasopressin expression using immunohistochemistry and antibodies directed against vasopressin (anti-VP) and against vasopressin-associated glycopeptide (anti-VAG). All cases examined were negative for vasopressin gene expression using these antibodies. Alternatively, we examined 16 cases of breast ductal carcinoma in situ (DCIS) using the second of these antibodies (anti-VAG), and all of these cases were positive for vasopressin gene expression. Our results suggest that products of vasopressin gene expression are not markers of cellular proliferation in the breast, and might rather represent an early part of the carcinogenic process in this tissue.