Kristi Elkins - Academia.edu (original) (raw)

Papers by Kristi Elkins

Research paper thumbnail of Supplementary Figure 1 from Loss of NAPRT1 Expression by Tumor-Specific Promoter Methylation Provides a Novel Predictive Biomarker for NAMPT Inhibitors

Research paper thumbnail of Supplementary Methods and Tables from Loss of NAPRT1 Expression by Tumor-Specific Promoter Methylation Provides a Novel Predictive Biomarker for NAMPT Inhibitors

The concentration of NAD in cells was determined by a non-validated liquid chromatography-tandem ... more The concentration of NAD in cells was determined by a non-validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay using 13 C 5-NAD as an internal standard (IS). 150µL of 0.5 N perchloric acid was added to each cell

Research paper thumbnail of CD40 Pathway Activation Status Predicts Response to CD40 Targeted Therapy in Diffuse Large b-Cell Lymphoma

Blood, Nov 20, 2009

Abstract 2721 Poster Board II-697 The role of the CD40 pathway in B-cell cancers is rather enigma... more Abstract 2721 Poster Board II-697 The role of the CD40 pathway in B-cell cancers is rather enigmatic due to having polar opposite roles in tumor biology. Stimulation of the CD40 receptor can reduce cell viability of NHL cell lines and xenograft tumor models, whereas, in sharp contrast, constitutive CD40 stimulation can actually promote proliferation of NHL cell lines, as well as drive lymphomagenesis and transformation of primary B-cells. Therefore, targeting the CD40 pathway has been challenging due to a knowledge gap in understanding the factors that may dictate a pro- or anti-tumor role. To address this directly, we employed a large panel of NHL cell lines and xenografts models to simulate a patient population and to define the molecular parameters to test in the context of clinical trials. Using baseline gene expression profiling, we found that the in vitro activity of an antibody that stimulates the CD40 pathway, Dacetuzumab (SGN-40), correlated strikingly with a transcriptional profile that was representative of an inactive CD40 pathway. Resistant cells, on the other hand, displayed a transcriptional profile indicative of an activated CD40 pathway. Consistent with these observations, constitutive phosphorylation of ERK, a node downstream of CD40 signaling, was present predominantly in cell lines that were resistant to Dacetuzumab. Fifteen genes, based on their association with in vitro activity and their biology as components of the CD40 network, were selected as a classifier from these pre-clinical data and independently tested in a panel of cell lines and xenografts models. Testing the selected gene classifier by qRT-PCR from baseline fixed tumor tissue of 39 patients treated with Dacetuzumab in phase I and II clinical trials revealed the ability to predict sensitivity in patients, as determined by tumor shrinkage…

Research paper thumbnail of Supplementary Table 1 from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

XLSX file - 30K, IC50 concentrations and CD22 expression levels for cell lines.

Research paper thumbnail of Supplementary Figure 3 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 48KB, In vivo efficacy of anti-FcRL5-MC-vc-PAB-MMAE in combination with bortezomib

Research paper thumbnail of Supplementary Figure 1 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 282KB, In vivo efficacy of anti-FcRL5 ADCs with different linker-drugs

Research paper thumbnail of Data from Loss of NAPRT1 Expression by Tumor-Specific Promoter Methylation Provides a Novel Predictive Biomarker for NAMPT Inhibitors

Purpose: We sought to identify predictive biomarkers for a novel nicotinamide phosphoribosyltrans... more Purpose: We sought to identify predictive biomarkers for a novel nicotinamide phosphoribosyltransferase (NAMPT) inhibitor. Experimental Design: We use a NAMPT inhibitor, GNE-617, to evaluate nicotinic acid rescue status in a panel of more than 400 cancer cell lines. Using correlative analysis and RNA interference (RNAi), we identify a specific biomarker for nicotinic acid rescue status. We next determine the mechanism of regulation of expression of the biomarker. Finally, we develop immunohistochemical (IHC) and DNA methylation assays and evaluate cancer tissue for prevalence of the biomarker across indications. Results: Nicotinate phosphoribosyltransferase (NAPRT1) is necessary for nicotinic acid rescue and its expression is the major determinant of rescue status. We demonstrate that NAPRT1 promoter methylation accounts for NAPRT1 deficiency in cancer cells, and NAPRT1 methylation is predictive of rescue status in cancer cell lines. Bisulfite next-generation sequencing mapping of the NAPRT1 promoter identified tumor-specific sites of NAPRT1 DNA methylation and enabled the development of a quantitative methylation-specific PCR (QMSP) assay suitable for use on archival formalin-fixed paraffin-embedded tumor tissue. Conclusions: Tumor-specific promoter hypermethylation of NAPRT1 inactivates one of two NAD salvage pathways, resulting in synthetic lethality with the coadministration of a NAMPT inhibitor. NAPRT1 expression is lost due to promoter hypermethylation in most cancer types evaluated at frequencies ranging from 5% to 65%. NAPRT1-specific immunohistochemical or DNA methylation assays can be used on archival formalin paraffin-embedded cancer tissue to identify patients likely to benefit from coadministration of a Nampt inhibitor and nicotinic acid. Clin Cancer Res; 19(24); 6912-23. Ó2013 AACR.

Research paper thumbnail of Supplementary Figure 1 from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

PDF file - 61K, Supplemental Figure 1. Human, cynomolgus monkey, and rat PBMCs were isolated from... more PDF file - 61K, Supplemental Figure 1. Human, cynomolgus monkey, and rat PBMCs were isolated from whole blood in accordance with BD Vacutainer CPT protocol. Mouse PBMCs were isolated from whole blood by ACK lysis buffer treatment to lyse red blood cells followed by centrifucation to recover PBMCs. Human antibodies were labeled in accordance with the protocol with Zenon Alexa Fluor 647 Human IgG Labeling Kit. Mean fluorescent intensity (MFI) was calculated from the CD20‑positive B cells (human and cynomolgus monkey), CD45RA‑positive B cells (rat), or CD45R‑positive B cells (mouse).

Research paper thumbnail of Supplementary Figure Legends from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

Research paper thumbnail of Data from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

Research paper thumbnail of Supplementary Figure 2 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

Research paper thumbnail of Data from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

Fc receptor-like 5 (FcRL5/FcRH5/IRTA2/CD307) is a surface protein expressed selectively on B cell... more Fc receptor-like 5 (FcRL5/FcRH5/IRTA2/CD307) is a surface protein expressed selectively on B cells and plasma cells. We found that FcRL5 was expressed at elevated levels on the surface of plasma cells from the bone marrow of patients diagnosed with multiple myeloma. This prevalence in multiple myeloma and narrow pattern of normal expression indicate that FcRL5 could be a target for antibody-based therapies for multiple myeloma, particularly antibody–drug conjugates (ADC), potent cytotoxic drugs linked to antibodies via specialized chemical linkers, where limited expression on normal tissues is a key component to their safety. We found that FcRL5 is internalized upon antibody binding, indicating that ADCs to FcRL5 could be effective. Indeed, we found that FcRL5 ADCs were efficacious in vitro and in vivo but the unconjugated antibody was not. The two most effective consisted of our anti-FcRL5 antibody conjugated through cysteines to monomethylauristatin E (MMAE) by a maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl (MC-vcPAB) linker (anti-FcRL5-MC-vcPAB-MMAE) or conjugated via lysines to the maytansinoid DM4 through a disulfide linker (anti-FcRL5-SPDB-DM4). These two ADCs were highly effective in vivo in combination with bortezomib or lenalidomide, drugs in use for the treatment of multiple myeloma. These data show that the FcRL5 ADCs described herein show promise as an effective treatment for multiple myeloma. Mol Cancer Ther; 11(10); 2222–32. ©2012 AACR.

Research paper thumbnail of Supplementary Table 1 from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

XLSX file - 30K, IC50 concentrations and CD22 expression levels for cell lines.

Research paper thumbnail of Supplementary Figure 1 from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

PDF file - 61K, Supplemental Figure 1. Human, cynomolgus monkey, and rat PBMCs were isolated from... more PDF file - 61K, Supplemental Figure 1. Human, cynomolgus monkey, and rat PBMCs were isolated from whole blood in accordance with BD Vacutainer CPT protocol. Mouse PBMCs were isolated from whole blood by ACK lysis buffer treatment to lyse red blood cells followed by centrifucation to recover PBMCs. Human antibodies were labeled in accordance with the protocol with Zenon Alexa Fluor 647 Human IgG Labeling Kit. Mean fluorescent intensity (MFI) was calculated from the CD20‑positive B cells (human and cynomolgus monkey), CD45RA‑positive B cells (rat), or CD45R‑positive B cells (mouse).

Research paper thumbnail of Supplementary Figure Legends from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

Research paper thumbnail of Supplementary Data from Nonclinical Efficacy and Safety of CX-2029, an Anti-CD71 Probody–Drug Conjugate

Supplementary Data from Nonclinical Efficacy and Safety of CX-2029, an Anti-CD71 Probody–Drug Con... more Supplementary Data from Nonclinical Efficacy and Safety of CX-2029, an Anti-CD71 Probody–Drug Conjugate

Research paper thumbnail of Supplementary Figure 3 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 48KB, In vivo efficacy of anti-FcRL5-MC-vc-PAB-MMAE in combination with bortezomib

Research paper thumbnail of Supplementary Figure 1 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 282KB, In vivo efficacy of anti-FcRL5 ADCs with different linker-drugs

Research paper thumbnail of Supplementary Figure 2 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 62KB, In vivo efficacy of anti-FcRL5-SPDB-DM4 in combination with bortezomib

Research paper thumbnail of Supplementary Figure 4 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 48KB, In vivo efficacy of anti-FcRL5-MC-vc-PAB-MMAE in combination with lenalidomide

Research paper thumbnail of Supplementary Figure 1 from Loss of NAPRT1 Expression by Tumor-Specific Promoter Methylation Provides a Novel Predictive Biomarker for NAMPT Inhibitors

Research paper thumbnail of Supplementary Methods and Tables from Loss of NAPRT1 Expression by Tumor-Specific Promoter Methylation Provides a Novel Predictive Biomarker for NAMPT Inhibitors

The concentration of NAD in cells was determined by a non-validated liquid chromatography-tandem ... more The concentration of NAD in cells was determined by a non-validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay using 13 C 5-NAD as an internal standard (IS). 150µL of 0.5 N perchloric acid was added to each cell

Research paper thumbnail of CD40 Pathway Activation Status Predicts Response to CD40 Targeted Therapy in Diffuse Large b-Cell Lymphoma

Blood, Nov 20, 2009

Abstract 2721 Poster Board II-697 The role of the CD40 pathway in B-cell cancers is rather enigma... more Abstract 2721 Poster Board II-697 The role of the CD40 pathway in B-cell cancers is rather enigmatic due to having polar opposite roles in tumor biology. Stimulation of the CD40 receptor can reduce cell viability of NHL cell lines and xenograft tumor models, whereas, in sharp contrast, constitutive CD40 stimulation can actually promote proliferation of NHL cell lines, as well as drive lymphomagenesis and transformation of primary B-cells. Therefore, targeting the CD40 pathway has been challenging due to a knowledge gap in understanding the factors that may dictate a pro- or anti-tumor role. To address this directly, we employed a large panel of NHL cell lines and xenografts models to simulate a patient population and to define the molecular parameters to test in the context of clinical trials. Using baseline gene expression profiling, we found that the in vitro activity of an antibody that stimulates the CD40 pathway, Dacetuzumab (SGN-40), correlated strikingly with a transcriptional profile that was representative of an inactive CD40 pathway. Resistant cells, on the other hand, displayed a transcriptional profile indicative of an activated CD40 pathway. Consistent with these observations, constitutive phosphorylation of ERK, a node downstream of CD40 signaling, was present predominantly in cell lines that were resistant to Dacetuzumab. Fifteen genes, based on their association with in vitro activity and their biology as components of the CD40 network, were selected as a classifier from these pre-clinical data and independently tested in a panel of cell lines and xenografts models. Testing the selected gene classifier by qRT-PCR from baseline fixed tumor tissue of 39 patients treated with Dacetuzumab in phase I and II clinical trials revealed the ability to predict sensitivity in patients, as determined by tumor shrinkage…

Research paper thumbnail of Supplementary Table 1 from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

XLSX file - 30K, IC50 concentrations and CD22 expression levels for cell lines.

Research paper thumbnail of Supplementary Figure 3 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 48KB, In vivo efficacy of anti-FcRL5-MC-vc-PAB-MMAE in combination with bortezomib

Research paper thumbnail of Supplementary Figure 1 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 282KB, In vivo efficacy of anti-FcRL5 ADCs with different linker-drugs

Research paper thumbnail of Data from Loss of NAPRT1 Expression by Tumor-Specific Promoter Methylation Provides a Novel Predictive Biomarker for NAMPT Inhibitors

Purpose: We sought to identify predictive biomarkers for a novel nicotinamide phosphoribosyltrans... more Purpose: We sought to identify predictive biomarkers for a novel nicotinamide phosphoribosyltransferase (NAMPT) inhibitor. Experimental Design: We use a NAMPT inhibitor, GNE-617, to evaluate nicotinic acid rescue status in a panel of more than 400 cancer cell lines. Using correlative analysis and RNA interference (RNAi), we identify a specific biomarker for nicotinic acid rescue status. We next determine the mechanism of regulation of expression of the biomarker. Finally, we develop immunohistochemical (IHC) and DNA methylation assays and evaluate cancer tissue for prevalence of the biomarker across indications. Results: Nicotinate phosphoribosyltransferase (NAPRT1) is necessary for nicotinic acid rescue and its expression is the major determinant of rescue status. We demonstrate that NAPRT1 promoter methylation accounts for NAPRT1 deficiency in cancer cells, and NAPRT1 methylation is predictive of rescue status in cancer cell lines. Bisulfite next-generation sequencing mapping of the NAPRT1 promoter identified tumor-specific sites of NAPRT1 DNA methylation and enabled the development of a quantitative methylation-specific PCR (QMSP) assay suitable for use on archival formalin-fixed paraffin-embedded tumor tissue. Conclusions: Tumor-specific promoter hypermethylation of NAPRT1 inactivates one of two NAD salvage pathways, resulting in synthetic lethality with the coadministration of a NAMPT inhibitor. NAPRT1 expression is lost due to promoter hypermethylation in most cancer types evaluated at frequencies ranging from 5% to 65%. NAPRT1-specific immunohistochemical or DNA methylation assays can be used on archival formalin paraffin-embedded cancer tissue to identify patients likely to benefit from coadministration of a Nampt inhibitor and nicotinic acid. Clin Cancer Res; 19(24); 6912-23. Ó2013 AACR.

Research paper thumbnail of Supplementary Figure 1 from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

PDF file - 61K, Supplemental Figure 1. Human, cynomolgus monkey, and rat PBMCs were isolated from... more PDF file - 61K, Supplemental Figure 1. Human, cynomolgus monkey, and rat PBMCs were isolated from whole blood in accordance with BD Vacutainer CPT protocol. Mouse PBMCs were isolated from whole blood by ACK lysis buffer treatment to lyse red blood cells followed by centrifucation to recover PBMCs. Human antibodies were labeled in accordance with the protocol with Zenon Alexa Fluor 647 Human IgG Labeling Kit. Mean fluorescent intensity (MFI) was calculated from the CD20‑positive B cells (human and cynomolgus monkey), CD45RA‑positive B cells (rat), or CD45R‑positive B cells (mouse).

Research paper thumbnail of Supplementary Figure Legends from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

Research paper thumbnail of Data from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

Research paper thumbnail of Supplementary Figure 2 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

Research paper thumbnail of Data from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

Fc receptor-like 5 (FcRL5/FcRH5/IRTA2/CD307) is a surface protein expressed selectively on B cell... more Fc receptor-like 5 (FcRL5/FcRH5/IRTA2/CD307) is a surface protein expressed selectively on B cells and plasma cells. We found that FcRL5 was expressed at elevated levels on the surface of plasma cells from the bone marrow of patients diagnosed with multiple myeloma. This prevalence in multiple myeloma and narrow pattern of normal expression indicate that FcRL5 could be a target for antibody-based therapies for multiple myeloma, particularly antibody–drug conjugates (ADC), potent cytotoxic drugs linked to antibodies via specialized chemical linkers, where limited expression on normal tissues is a key component to their safety. We found that FcRL5 is internalized upon antibody binding, indicating that ADCs to FcRL5 could be effective. Indeed, we found that FcRL5 ADCs were efficacious in vitro and in vivo but the unconjugated antibody was not. The two most effective consisted of our anti-FcRL5 antibody conjugated through cysteines to monomethylauristatin E (MMAE) by a maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl (MC-vcPAB) linker (anti-FcRL5-MC-vcPAB-MMAE) or conjugated via lysines to the maytansinoid DM4 through a disulfide linker (anti-FcRL5-SPDB-DM4). These two ADCs were highly effective in vivo in combination with bortezomib or lenalidomide, drugs in use for the treatment of multiple myeloma. These data show that the FcRL5 ADCs described herein show promise as an effective treatment for multiple myeloma. Mol Cancer Ther; 11(10); 2222–32. ©2012 AACR.

Research paper thumbnail of Supplementary Table 1 from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

XLSX file - 30K, IC50 concentrations and CD22 expression levels for cell lines.

Research paper thumbnail of Supplementary Figure 1 from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma

PDF file - 61K, Supplemental Figure 1. Human, cynomolgus monkey, and rat PBMCs were isolated from... more PDF file - 61K, Supplemental Figure 1. Human, cynomolgus monkey, and rat PBMCs were isolated from whole blood in accordance with BD Vacutainer CPT protocol. Mouse PBMCs were isolated from whole blood by ACK lysis buffer treatment to lyse red blood cells followed by centrifucation to recover PBMCs. Human antibodies were labeled in accordance with the protocol with Zenon Alexa Fluor 647 Human IgG Labeling Kit. Mean fluorescent intensity (MFI) was calculated from the CD20‑positive B cells (human and cynomolgus monkey), CD45RA‑positive B cells (rat), or CD45R‑positive B cells (mouse).

Research paper thumbnail of Supplementary Figure Legends from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

Research paper thumbnail of Supplementary Data from Nonclinical Efficacy and Safety of CX-2029, an Anti-CD71 Probody–Drug Conjugate

Supplementary Data from Nonclinical Efficacy and Safety of CX-2029, an Anti-CD71 Probody–Drug Con... more Supplementary Data from Nonclinical Efficacy and Safety of CX-2029, an Anti-CD71 Probody–Drug Conjugate

Research paper thumbnail of Supplementary Figure 3 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 48KB, In vivo efficacy of anti-FcRL5-MC-vc-PAB-MMAE in combination with bortezomib

Research paper thumbnail of Supplementary Figure 1 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 282KB, In vivo efficacy of anti-FcRL5 ADCs with different linker-drugs

Research paper thumbnail of Supplementary Figure 2 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 62KB, In vivo efficacy of anti-FcRL5-SPDB-DM4 in combination with bortezomib

Research paper thumbnail of Supplementary Figure 4 from FcRL5 as a Target of Antibody–Drug Conjugates for the Treatment of Multiple Myeloma

PDF file - 48KB, In vivo efficacy of anti-FcRL5-MC-vc-PAB-MMAE in combination with lenalidomide