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High levels of IL1β can result in chronic inflammation, which in turn can promote tumor growth and metastasis. Inhibition of IL1β could therefore be a promising therapeutic option in the treatment of cancer. Here, the effects of IL1β blockade induced by the mAbs canakinumab and gevokizumab were evaluated alone or in combination with docetaxel, anti–programmed cell death protein 1 (anti–PD-1), anti-VEGFα, and anti-TGFβ treatment in syngeneic and humanized mouse models of cancers of different origin. Canakinumab and gevokizumab did not show notable efficacy as single-agent therapies; however, IL1β blockade enhanced the effectiveness of docetaxel and anti–PD-1. Accompanying these effects, blockade of IL1β alone or in combination induced significant remodeling of the tumor microenvironment (TME), with decreased numbers of immune suppressive cells and increased tumor infiltration by dendritic cells (DC) and effector T cells. Further investigation revealed that cancer-associated fibroblasts (CAF) were the cell type most affected by treatment with canakinumab or gevokizumab in terms of change in gene expression. IL1β inhibition drove phenotypic changes in CAF populations, particularly those with the ability to influence immune cell recruitment. These results suggest that the observed remodeling of the TME following IL1β blockade may stem from changes in CAF populations. Overall, the results presented here support the potential use of IL1β inhibition in cancer treatment. Further exploration in ongoing clinical studies will help identify the best combination partners for different cancer types, cancer stages, and lines of treatment.

Purpose: Claudin-6 (CLDN6) is expressed at elevated levels in multiple human cancers including ovarian and endometrial malignancies, with little or no detectable expression in normal adult tissue. This expression profile makes CLDN6 an ideal target for development of a potential therapeutic antibody–drug conjugate (ADC). This study describes the generation and preclinical characterization of CLDN6–23-ADC, an ADC consisting of a humanized anti-CLDN6 monoclonal antibody coupled to monomethyl auristatin E (MMAE) via a cleavable linker. Experimental Design: A fully humanized anti-CLDN6 antibody was conjugated to MMAE resulting in the potential therapeutic ADC, CLDN6–23-ADC. The antitumor efficacy of CLDN6–23-ADC was assessed for antitumor efficacy in CLDN6-positive (CLDN6+) and -negative (CLDN6−) xenografts and patient-derived xenograft (PDX) models of human cancers. Results: CLDN6–23-ADC selectively binds to CLDN6, versus other CLDN family members, inhibits the proliferation of CLDN6+ cancer cells in vitro, and is rapidly internalized in CLDN6+ cells. Robust tumor regressions were observed in multiple CLDN6+ xenograft models and tumor inhibition led to markedly enhanced survival of CLDN6+ PDX tumors following treatment with CLDN6–23-ADC. IHC assessment of cancer tissue microarrays demonstrate elevated levels of CLDN6 in 29% of ovarian epithelial carcinomas. Approximately 45% of high-grade serous ovarian carcinomas and 11% of endometrial carcinomas are positive for the target. Conclusions: We report the development of a novel ADC, CLDN6–23-ADC, that selectively targets CLDN6, a potential onco-fetal-antigen which is highly expressed in ovarian and endometrial cancers. CLDN6–23-ADC exhibits robust tumor regressions in mouse models of human ovarian and endometrial cancers and is currently undergoing phase I study.

Supplementary tables S1-S5 and figures S1-S7

High levels of IL1β can result in chronic inflammation, which in turn can promote tumor growth and metastasis. Inhibition of IL1β could therefore be a promising therapeutic option in the treatment of cancer. Here, the effects of IL1β blockade induced by the mAbs canakinumab and gevokizumab were evaluated alone or in combination with docetaxel, anti–programmed cell death protein 1 (anti–PD-1), anti-VEGFα, and anti-TGFβ treatment in syngeneic and humanized mouse models of cancers of different origin. Canakinumab and gevokizumab did not show notable efficacy as single-agent therapies; however, IL1β blockade enhanced the effectiveness of docetaxel and anti–PD-1. Accompanying these effects, blockade of IL1β alone or in combination induced significant remodeling of the tumor microenvironment (TME), with decreased numbers of immune suppressive cells and increased tumor infiltration by dendritic cells (DC) and effector T cells. Further investigation revealed that cancer-associated fibroblasts (CAF) were the cell type most affected by treatment with canakinumab or gevokizumab in terms of change in gene expression. IL1β inhibition drove phenotypic changes in CAF populations, particularly those with the ability to influence immune cell recruitment. These results suggest that the observed remodeling of the TME following IL1β blockade may stem from changes in CAF populations. Overall, the results presented here support the potential use of IL1β inhibition in cancer treatment. Further exploration in ongoing clinical studies will help identify the best combination partners for different cancer types, cancer stages, and lines of treatment.

Antibiotic resistance in bacteria, especially Gram-positive bacteria like

Supplemental Figure S2: Amino acid sequence alignment of CLDN6 (P56747) and CLDN9 (O95484) with the extracellular loops highlighted

Methods for Supplemental Data

Purpose:Claudin-6 (CLDN6) is expressed at elevated levels in multiple human cancers including ovarian and endometrial malignancies, with little or no detectable expression in normal adult tissue. This expression profile makes CLDN6 an ideal target for development of a potential therapeutic antibody–drug conjugate (ADC). This study describes the generation and preclinical characterization of CLDN6–23-ADC, an ADC consisting of a humanized anti-CLDN6 monoclonal antibody coupled to monomethyl auristatin E (MMAE) via a cleavable linker.Experimental Design:A fully humanized anti-CLDN6 antibody was conjugated to MMAE resulting in the potential therapeutic ADC, CLDN6–23-ADC. The antitumor efficacy of CLDN6–23-ADC was assessed for antitumor efficacy in CLDN6-positive (CLDN6+) and -negative (CLDN6−) xenografts and patient-derived xenograft (PDX) models of human cancers.Results:CLDN6–23-ADC selectively binds to CLDN6, versus other CLDN family members, inhibits the proliferation of CLDN6+ cancer cells in vitro, and is rapidly internalized in CLDN6+ cells. Robust tumor regressions were observed in multiple CLDN6+ xenograft models and tumor inhibition led to markedly enhanced survival of CLDN6+ PDX tumors following treatment with CLDN6–23-ADC. IHC assessment of cancer tissue microarrays demonstrate elevated levels of CLDN6 in 29% of ovarian epithelial carcinomas. Approximately 45% of high-grade serous ovarian carcinomas and 11% of endometrial carcinomas are positive for the target.Conclusions:We report the development of a novel ADC, CLDN6–23-ADC, that selectively targets CLDN6, a potential onco-fetal-antigen which is highly expressed in ovarian and endometrial cancers. CLDN6–23-ADC exhibits robust tumor regressions in mouse models of human ovarian and endometrial cancers and is currently undergoing phase I study.

File containing supplemental data

PDF file, 66K, Quantification of proteins from Western blots in Supplementary Figure S7 by densitometry using ImageJ software.

EMP2 and ALDH1 staining in breast cancer

PDF file, 58K.

Supplementary Figure 2 PDF file - 91K, Speed of recovery of downstream targets in NCI-N87

Supplementary Table 1 PDF file - 69K, NVP-AUY922 IC50 concentrations and response to trastuzumab in HER2 amplified breast cancer cell lines

PDF file, 77K, Comparison of the effect of dacomitinib at 48 hrs and 5 days on cell cycle and apoptosis in BT-474 and SK-BR-3 lines.

Selected functional pathways affected by changes in EMP2 expression.

Supplemental Methods

PDF file, 55K.

PDF file, 60K, Effect of dacomitinib on apoptosis in BT-474 and SK-BR-3 parental lines and lines resistant to trastuzumab and lapatinib.

PDF file, 68K, Quantification of proteins from Western blots in Figure 3 by densitometry using ImageJ software.

Supplementary Legends PDF file - 78K, Supplementary Figure Legends

Supplementary Table from Tucatinib has Selective Activity in HER2-Positive Cancers and Significant Combined Activity with Approved and Novel Breast Cancer–Targeted Therapies

The human EGF (HER) family of receptors has been pursued as therapeutic targets in breast cancer and other malignancies. Trastuzumab and lapatinib are standard treatments for HER2-amplified breast cancer, but a significant number of patients do not respond or develop resistance to these drugs. Here we evaluate the in vitro activity of dacomitinib (PF-00299804), an irreversible small molecule pan-HER inhibitor, in a large panel of human breast cancer cell lines with variable expression of the HER family receptors and ligands, and with variable sensitivity to trastuzumab and lapatinib. Forty-seven human breast cancer and immortalized breast epithelial lines representing the known molecular subgroups of breast cancer were treated with dacomitinib to determine IC50 values. HER2-amplified lines were far more likely to respond to dacomitinib than nonamplified lines (RR, 3.39; P < 0.0001). Furthermore, HER2 mRNA and protein expression were quantitatively associated with response. Dacomitinib reduced the phosphorylation of HER2, EGFR, HER4, AKT, and ERK in the majority of sensitive lines. Dacomitinib exerted its antiproliferative effect through a combined G0–G1 arrest and an induction of apoptosis. Dacomitinib inhibited growth in several HER2-amplified lines with de novo and acquired resistance to trastuzumab. Dacomitinib maintained a high activity in lines with acquired resistance to lapatinib. This study identifies HER2-amplified breast cancer lines as most sensitive to the antiproliferative effect of dacomitinib and provides a strong rationale for its clinical testing in HER2-amplified breast cancers resistant to trastuzumab and lapatinib. Mol Cancer Ther; 11(9); 1978–87. ©2012 AACR.

PDF file, 247K, The effects of dacomitinib on protein expression in lines resistant to trastuzumab and lapatinib.

Supplementary Figure 3 PDF file - 58K, Activation of HSP70 in both N87-Parental and N87-TRC cell lines

PDF file, 75K, Dacomitinib response is marginally inversely correlated with relative HER3 mRNA levels.

PDF file, 50K, Effect of dacomitinib on cell cycle in BT-474 and SK-BR-3 parental lines and lines resistant to trastuzumab and lapatinib.

PDF file, 45K, Dacomitinib response is associated with the total HER2 protein levels in HER2-amplified cell lines.

Pharmacologically targeting the HER2 oncoprotein with therapeutics such as the mAb, trastuzumab, provides clinical benefit for patients with HER2-positive (HER2+) cancers. However, a significant number of patients eventually progress on these therapies. Efforts to overcome therapeutic resistance through combination therapy with small-molecule inhibitors of HER2 have been limited by toxicities associated with off-target activity and/or limited efficacy. In this preclinical study, we explore single-agent and combined activity of tucatinib, a novel HER2-selective small-molecule inhibitor. Tucatinib demonstrated potent, selective activity in a panel of 456 human cancer cell lines, with activity restricted to cell lines (breast and non-breast) with HER2-amplification, including models of acquired resistance to trastuzumab. Within the HER2+ population, tucatinib response tracked strongly with HER2-driven signaling. Single-agent tucatinib induced tumor regressions in xenograft models of HER2+ breast cancer and combination with trastuzumab induced a complete and sustained blockade of HER2/PI3K/AKT signaling. Efficacy of the tucatinib/trastuzumab combination matched that induced by current standard-of-care trastuzumab/pertuzumab/docetaxel combination, with the exception that the chemotherapy-sparing tucatinib/trastuzumab combination did not require a dosing holiday to achieve the same efficacy. In xenograft models of HER2+ breast cancer that also express estrogen receptor (ER; HER2+/ER+), tucatinib showed combined efficacy with inhibitors of CDK4/6 and ER, indicating potential novel therapeutic strategies for difficult-to-treat subtypes of HER2+ breast cancer. These data support expanded clinical investigations of tucatinib as a combination partner for other novel and approved targeted therapies for HER2-driven malignancies.

PDF file, 60K, Dacomitinib response is associated with relative HER2 mRNA levels.

Little is known about the role of epithelial membrane protein-2 (EMP2) in breast cancer development or progression. In this study, we tested the hypothesis that EMP2 may regulate the formation or self-renewal of breast cancer stem cells (BCSC) in the tumor microenvironment. In silico analysis of gene expression data demonstrated a correlation of EMP2 expression with known metastasis-related genes and markers of cancer stem cells (CSC) including aldehyde dehydrogenase (ALDH). In breast cancer cell lines, EMP2 overexpression increased and EMP2 knockdown decreased the proportion of stem-like cells as assessed by the expression of the CSC markers CD44+/CD24−, ALDH activity, or by tumor sphere formation. In vivo, upregulation of EMP2 promoted tumor growth, whereas knockdown reduced the ALDHhigh CSC population as well as retarded tumor growth. Mechanistically, EMP2 functionally regulated the response to hypoxia through the upregulation of HIF-1α, a transcription factor previously shown to regulate the self-renewal of ALDHhigh CSCs. Furthermore, in syngeneic mouse models and primary human tumor xenografts, mAbs directed against EMP2 effectively targeted CSCs, reducing the ALDH+ population and blocking their tumor-initiating capacity when implanted into secondary untreated mice. Collectively, our results show that EMP2 increases the proportion of tumor-initiating cells, providing a rationale for the continued development of EMP2-targeting agents.

PDF file - 60K

Supplementary Table 2 from Activated Phosphoinositide 3-Kinase/AKT Signaling Confers Resistance to Trastuzumab but not Lapatinib

Supplementary Table 1 from Activated Phosphoinositide 3-Kinase/AKT Signaling Confers Resistance to Trastuzumab but not Lapatinib

PDF file - 40K, Figure S2: Biomarkers of in vivo response to inhibitors of PI3K/mTOR signaling. Reverse Phase Protein Analysis (RPPA) of KPL-1 tumor samples taken after 7 days treatment with the molecules indicated. Tumors taken 24 hours post final dose. A, pAKT Ser473. B, pS6 Ser235/236.

PDF file - 36K, Figure S3. Xenograft response data for 7-day tissue acquisition studies. A-C, SUM190, UACC812 and KPL-1 xenografts (6 mice per arm) were treated with BKM120 at 35 mg/kg, BYL719 at 50 mg/kg, RAD001 at 10 mg/kg and BEZ235 at 30 mg/kg, all daily PO. Trastuzumab was given at given at 10 mg/kg IP twice weekly. For SUM190 (A), tumors were collected 2.5 hours post final dose, for UACC812 (B) and KPL-1 (C), samples were collected 24 hours post final dose.