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161
Background: DKK1 is a modulator of Wnt signaling that is frequently overexpressed in tumors and such expression has been associated with worse survival. Preclinical studies have ...shown that DKK1 can promote tumor growth by increasing angiogenesis and contributing to an immunosuppressive tumor microenvironment. DKN-01 is a humanized IgG4 monoclonal antibody against DKK1 that has shown encouraging efficacy signals in patients (pts) with advanced esophageal (EC) or esophagogastric junction (EGJ) cancer when administered in combination with paclitaxel. Correlative studies are evaluating DKK1 expression and genetics in archived tumor specimens and baseline and on-treatment plasma levels of angiogenesis and inflammation biomarkers as predictors of response. Methods: Formalin fixed paraffin embedded (FFPE) archived tumor tissue was evaluated for DKK1 expression by immunohistochemistry (IHC) and scored for fraction of positive cells, intensity, and localization of DKK1. Genetics were collected if known and/or performed using an Archer VariantPlex Solid Tumor Panel covering 67 genes. Plasma samples, pre- and on DKN-01 treatment were evaluated by multiplexed array for angiogenesis (bFGF, PIGF/PGF, sFLT1/sVEGFR1, sTIE-2/TEK, VEGF, VEGF-C, and VEGF-D) and inflammation (IFN-γ, TNF-α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70 and IL-13) markers (Meso-Scale Discovery) and by ELISA for HGF and SDF-1α (R&D Systems). Results: ~90% of tissue samples showed DKK1+ expression in tumor cells (range 1 to 100%); intensity (weak 1+ to strong 3+); and localization (cytoplasmic and/or nuclear). Early data has not identified a correlation between DKK1 staining and response. One pt with an ongoing durable response had an activating mutation in β-catenin. Analysis of plasma biomarkers is ongoing. Conclusions: Analysis of DKK1 staining, tumor genetics, and prospective angiogenic/inflammatory biomarkers are ongoing to identify a predictive biomarker for DKN-01. The majority of EC/EGJ tumor biopsies were IHC DKK1+. Broader genomic screens are underway to further characterize DKN-01 sensitivity; mechanistically plausible activating mutations in β-catenin may be a biomarker for DKN-01. Clinical trial information: NCT02013154.
Abstract only
48
Background: C-terminal binding protein 2 (CtBP2) is an oncogenic transcription factor that promotes cancer stem cell (CSC) growth and self-renewal, and controls pathways for tumor ...initiation, progression, and response to therapy. Expression of CtBP2 is linked to aggressive behavior in ovarian cancer, while genetic or pharmacologic targeting of CtBP2 disrupts CSC growth and self-renewal. CD44 is a cell surface marker that has been linked to CSC populations in many solid tumors, though data is conflicting on its role as tumor suppressor or oncogene. Gastrointestinal stromal tumors (GIST) is an increasingly common malignancy where risk stratification is essential for guiding post-surgical adjuvant therapy. We hypothesized that CtBP2 and CD44 staining would enhance risk stratification of GIST which currently relies on purely non-molecular clinicopathologic criteria. Methods: We identified 149 GIST cases from 1990 to 2016 in the Virginia Commonwealth University Medical Center pathology archive. Clinical data for 121 patients was available. The Armed Forces Institute of Pathology (AFIP) criteria (Miettinen's criteria) was used to risk stratify GISTs using the size, site, and mitotic index of the primary tumor. Immunohistochemistry for CtBP2 and CD44 was then performed on GIST samples with adequate tumor (86, CD44; 87, CtBP2). Stains were scored 0 (negative) to 3 (maximum) by two independent pathologists. Statistical analysis (χ
2
) correlating AFIP risk category with CD44 and CtBP2 staining was performed using PRISM6. Results: Moderate and high risk GISTs, based on AFIP criteria, significantly correlated with high CtBP2 expression (score = 3, p = 0.046) and low CD44 expression (score = 0-2, p = 0.034). Conclusions: CD44 and CtBP2 staining can be used to risk stratify GIST, and may enhance and complement current clinical risk stratification systems. Our data also suggests a potential tumor suppressive role of CD44 in GIST. Additionally, based on our findings, investigation of therapeutics that target CtBP2 in GISTs should be pursued.
Aims
A recently characterized group of undifferentiated small round cell sarcomas harbours fusions of the genes
CIC
and
DUX
4
. Studies report a distinctive gene expression profile for these ...sarcomas, including expression of E26 transformation‐specific (
ETS
) family proto‐oncogenic transcription factors
ETV
1,
ETV
4
and
ETV
5
. To test the utility of an ancillary diagnostic technique for these tumours, we evaluated chromogenic
RNA
in‐situ
hybridization assays for
ETV
1
,
ETV
4
and
ETV
5
as diagnostic adjuncts for this emerging group of highly malignant sarcomas.
Methods and results
We tested six confirmed
CIC
–
DUX
4 sarcomas and 105 lesions in the differential, including 48 Ewing sarcomas for expression of
ETV
1
,
ETV
4
and
ETV
5
, scoring expression utilizing a previously validated scale.
ETV
1
and
ETV
4
were positive in five of six cases, while
ETV
5
was positive in six of six. No Ewing sarcoma or other sarcoma tested showed coexpression of these transcripts, while one ETV1/ETV4/ETV5 triple positive previously unclassified round cell sarcoma was identified as harbouring a
CIC
rearrangement by break‐apart fluorescence
in‐situ
hybridization (
FISH
).
Conclusion
We identified overexpression of
ETV
1
,
ETV
4
and
ETV
5
transcripts
in situ
in
CIC
–
DUX
4 sarcomas using a robust assay in routine archival sections. One previously unclassified round cell sarcoma showed
ETV
1/4/5
positivity, and was proved to harbour a
CIC
rearrangement by break‐apart
FISH
. The sensitivity and specificity observed with our
in‐situ
hybridization assay implies potential utility as an ancillary diagnostic technique, particularly when faced with limited biopsy samples.
Full text
Available for:
BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Aims A recently characterized group of undifferentiated small round cell sarcomas harbours fusions of the genes CIC and DUX4. Studies report a distinctive gene expression profile for these sarcomas, ...including expression of E26 transformation-specific (ETS) family proto-oncogenic transcription factors ETV1, ETV4 and ETV5. To test the utility of an ancillary diagnostic technique for these tumours, we evaluated chromogenic RNAin-situ hybridization assays for ETV1,ETV4 and ETV5 as diagnostic adjuncts for this emerging group of highly malignant sarcomas. Methods and results We tested six confirmed CIC-DUX4 sarcomas and 105 lesions in the differential, including 48 Ewing sarcomas for expression of ETV1,ETV4 and ETV5, scoring expression utilizing a previously validated scale. ETV1 and ETV4 were positive in five of six cases, while ETV5 was positive in six of six. No Ewing sarcoma or other sarcoma tested showed coexpression of these transcripts, while one ETV1/ETV4/ETV5 triple positive previously unclassified round cell sarcoma was identified as harbouring a CIC rearrangement by break-apart fluorescence in-situ hybridization (FISH). Conclusion We identified overexpression of ETV1,ETV4 and ETV5 transcripts in situ in CIC-DUX4 sarcomas using a robust assay in routine archival sections. One previously unclassified round cell sarcoma showed ETV1/4/5 positivity, and was proved to harbour a CIC rearrangement by break-apart FISH. The sensitivity and specificity observed with our in-situ hybridization assay implies potential utility as an ancillary diagnostic technique, particularly when faced with limited biopsy samples.
Full text
Available for:
BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Interactions between the Bcr/Abl kinase inhibitor STI571 (Gleevec, imatinib mesylate) and histone deacetylase inhibitors (HDIs) have been examined in STI571-sensitive and -resistant Bcr/Abl(+) human ...leukemia cells (K562 and LAMA 84). Cotreatment of K562 cells with 250 nM imatinib mesylate and 2.0 micro M suberoylanilide hydroxamic acid (SAHA) for 24 h, exposures that were minimally toxic alone, resulted in a marked increase in mitochondrial damage (e.g., cytochrome c, Smac/DIABLO, and apoptosis-inducing factor release), caspase activation, and apoptosis. Similar events were observed in other Bcr/Abl(+) cells (i.e., LAMA 84), and in cells exposed to STI571 in combination with the HDI sodium butyrate. Coexposure of cells to HDIs in conjunction with STI571 resulted in multiple perturbations in signaling and cell cycle-regulatory proteins, including down-regulation of Raf, phospho-mitogen-activated protein kinase kinase (MEK), phospho-extracellular signal-regulated kinase (ERK), phospho-Akt, phospho-signal transducers and activators of transcription 5, cyclin D1, and Mcl-1, accompanied by dephosphorylation and cleavage of retinoblastoma protein and a striking increase in phosphorylation of c-Jun NH(2)-terminal kinase. Coexposure of Bcr/Abl(+) cells to STI571 also blocked SAHA-mediated induction of p21(CIP1) and resulted in down-regulation of Bcr/Abl protein expression. STI571 and SAHA also interacted synergistically to induce apoptosis in STI571-resistant K562 and LAMA 84 cells that display increased Bcr/Abl protein expression. Lastly, inducible expression of a constitutively active MEK1/2 construct significantly attenuated SAHA/STI571-mediated apoptosis in K562 cells, implicating disruption of the Raf/MEK/ERK axis in synergistic antileukemic effects of this drug combination. Together, these findings indicate that combined exposure of Bcr/Abl(+) cells to the kinase inhibitor STI571 and HDIs leads to diverse perturbations in signaling and cell cycle-regulatory proteins, associated with a marked increase in mitochondrial damage and cell death. They also raise the possibility that this strategy may be effective in some Bcr/Abl(+) cells that are resistant to STI571 through increased Bcr/Abl expression.
Invasive fungal sinusitis is a morbid pathology that typically affects immunocompromised patients and may quickly progress to fulminant disease. The purpose of this study was to measure the ...sensitivity and specificity of touch preparation of nasal debridement specimens as a rapid diagnostic tool for invasive fungal sinusitis. A retrospective chart review was performed of 22 patients undergoing nasal debridement due to suspicion for invasive fungal sinusitis over a 10-year period. Thirteen patients had touch preparation of nasal specimens followed by routine histologic processing; two of these patients underwent 2, and 1 patient had 3 separate debridements, for a total of 17 touch preparations performed. The sensitivity and specificity of touch preparation were calculated by correlating the initial results with the presence of fungal invasion on final pathologic analysis. The sensitivity of touch preparation was 56% (95% confidence interval CI: 0.23-0.85), specificity was 100% (95% CI: 0.60-1.00), positive predictive value was 100% (95% CI: 0.46-1.00), and negative predictive value was 67% (95% CI: 0.35-0.89). This procedure may be a useful adjunct in situations requiring rapid diagnosis of invasive fungal sinusitis but should not be used as the sole criteria for determining the need for surgical intervention.
Abstract only
e22203
Background: Dkk-1 is an inhibitor of the canonical Wnt/β-catenin signaling pathway. Inhibition of Wnt pathway results in the stabilization of β-catenin, leading to target gene ...expression such as cyclin D1, c-myc, VEGF and other factors associated with cell growth. Elevated levels of serum Dkk-1 in a variety of tumor types are well established, and are hypothesized to have a negative prognostic value. Tumor tissue expression of Dkk-1 has not been systematically examined. We evaluated Dkk-1 expression in various tumors. Methods: Utilizing an anonymous banked tumor repository, we identified 119 patient samples (NSCLC (squamous, n=19; adenocarcinoma, n=47), esophageal (squamous, n=15; adenocarcinoma, n=17) and gastric (n=20)). Immunohistochemical (IHC) staining was performed using commercially available antibodies. One pathologist evaluated all slides using IHC staining quantification on a 4-point scale (0, 1+, 2+, 3+). Results: Dkk-1 expression is more pronounced in tumor tissues than peritumoral normal tissues of lung and esophagus. Unexpectedly, Dkk-1 expression is seen in two staining patterns, perinuclear and cytoplasmic that varied by primary location and histology. Conclusions: Elevated Dkk-1 expression is demonstrated in lung, esophageal and gastric cancer regardless of histology. All except squamous cell lung express perinuclear Dkk-1 more frequently than cytoplasmic pattern. Additional studies are needed to understand significance of these patterns and potentially define Dkk-1 as a novel therapeutic target in these malignancies. Table: see text
The functional significance of disruption of p21 WAF1 / CIP1 induction by flavopiridol (FP) in human leukemia cells (Jurkat) exposed to the histone deacetylase (HDAC) inhibitor sodium
butyrate (SB) ...was investigated. Coexposure of leukemic cells to FP blocked SB-mediated induction of p21 WAF1 / CIP1 and resulted in a marked increase in mitochondrial injury, activation of procaspases-3 and -8, Bid cleavage, and PARP degradation.
Enforced expression of p21 WAF1 / CIP1 (i.e., in Jurkat cells inducibly expressing p21 WAF1 / CIP1 under the control of a doxycycline-responsive promoter) partially but significantly reduced cytochrome c and apoptosis-inducing factor release, loss of mitochondrial membrane potential, caspase-3 and -8 activation, Bid cleavage,
poly(ADP-ribose)polymerase (PARP) degradation, and apoptosis in response to SB/FP. Furthermore, increasing expression of p21 WAF1 / CIP1 (i.e., by culturing cells in the presence of higher concentrations of doxycycline) rendered cells more resistant to SB/FP-mediated
lethality. Enforced expression of p21 WAF1 / CIP1 did not modify SB/FP-mediated JNK activation or generation of reactive oxygen species. Consistent with these results, Jurkat
cells stably expressing a p21 WAF1 / CIP1 nuclear localization mutant (p21ÎNLS) were also resistant to SB/FP-mediated mitochondrial injury, activation of procaspases-3
and -8, PARP cleavage, and apoptosis. Finally, enforced expression of full-length or ectopic expression of ÎNLS p21 WAF1 / CIP1 increased the amount of p21 WAF1 / CIP1 coimmunoprecipitating with procaspase-3. Together, these findings suggest that interruption of HDAC-mediated p21 WAF1 / CIP1 induction by FP plays a significant functional role in potentiating apoptosis, possibly by preventing the formation of a
procaspase-3/p21 WAF1 / CIP1 complex.
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