Probes for DKK1

Dickkopf-1 (DKK1) is a secreted modulator of Wnt signaling that is frequently overexpressed in tumors and associated with poor clinical outcomes. DKN-01 is a humanized monoclonal therapeutic antibody that binds DKK1 with high affinity and has demonstrated clinical activity in gastric/gastroesophageal junction (G/GEJ) patients with elevated tumoral expression of DKK1. Here we report on the validation of a DKK1 RNAscope chromogenic in situ hybridization assay to assess DKK1 expression in G/GEJ tumor tissue. To reduce pathologist time, potential pathologist variability from manual scoring and support pathologist decision making, a digital image analysis algorithm that identifies tumor cells and quantifies the DKK1 signal was developed. Following CLIA guidelines the DKK1 RNAscope chromogenic in situ hybridization assay and digital image analysis algorithm were successfully validated for sensitivity, specificity, accuracy, and precision. The DKK1 RNAscope assay in conjunction with the digital image analysis solution is acceptable for prospective screening of G/GEJ adenocarcinoma patients. The work described here will further advance the companion diagnostic development of our DKK1 RNAscope assay and could generally be used as a guide for the validation of RNAscope assays with digital image quantification.

Background Despite recent approval of anti-PD-1 antibodies as 1L therapy in advanced GEA, benefit is largely limited to PD-L1 combined positive scores (CPS) ≥5 patients (pts); novel therapeutic approaches are needed. DKN-01 is a targeted anti-DKK1 mAb which has demonstrated activity in GEA pts with elevated tumoral DKK1 expression, a subset of pts with more aggressive disease and shorter overall survival. Methods Phase IIa single arm trial investigating DKN-01 300 mg (D) + tislelizumab (TS) + CAPOX as 1L therapy in advanced HER2(-) GEA regardless of DKK1 status. Tumoral DKK1 mRNA expression was assessed by a chromogenic in situ hybridization RNAscope assay and assigned an H-score (0-300). Primary endpoint was ORR in modified intent to treat (mITT) population (>1 dose D); secondary endpoints included PFS and OS in intent to treat (ITT) population overall and by DKK1 expression: high (H-score ≥35) vs low. Results 25 pts enrolled (01 Sept 2020 - 08 Apr 2021). Median age 61 years (22, 80); 17 pts gastroesophageal junction adenocarcinoma; 8 pts gastric cancer. 21 GEA pts had RNAscope DKK1 expression; 57% were DKK1-high. 22 of 25 pts had vCPS: 73% were vCPS

Background Dickkopf-1 (DKK1) modulates Wnt signaling and contributes to an immune suppressive tumor microenvironment. DKN-01 (D), a neutralizing DKK1 antibody, in combination with an anti-PD1 antibody, has demonstrated safety and clinical activity in advanced previously treated DKK1-high GEA. We report response and survival outcomes in GEA patients (pts) treated with D + tislelizumab (T) + capecitabine/oxaliplatin (CAPOX) as a first line therapy. Methods We enrolled advanced GEA pts in a phase IIa study of D + T + CAPOX (NCT04363801). Tumoral DKK1 mRNA expression was assessed by a chromogenic in situ hybridization RNAscope assay and assigned an H-score (0-300). Objective response rate (ORR) [primary efficacy objective], duration of response (DoR), disease control rate (DCR), and progression free survival (PFS) were evaluated in a modified intent to treat (mITT) population (completed ≥ 1 cycle) as well as compared between DKK1 high (H-score ≥35) and low groups. Results Twenty-five GEA pts were enrolled. Median age was 61 (22, 80); 19 males, 6 females. 17 pts (68%) had gastroesophageal junction (GEJ) adenocarcinoma; 8 pts (32%) had gastric cancer (GC). 18 GEA pts had RNAscope DKK1 expression available; 9 pts DKK1-high [5 GEJ, 4 GC) and 9 pts DKK1-low [7 GEJ, 2 GC]. Mean duration of treatment 3 mos, longest duration to date on study 7 mos, 19 pts remain on therapy. Most common D + T + CAPOX regimen related TEAEs were G1/2: anemia, thrombocytopenia, fatigue, diarrhea, nausea each in 3 pts. No related G3/4 toxicities; overall four G5 events; 1 related event pulmonary embolism. mITT analysis included 22 pts. Preliminary ORR in response evaluable (RE) mITT was 68% (13 PR, 6 SD, 1 NE, 2 pending first scan) and DCR 100%. In RE DKK1 high pts (n=7) there was an ORR of 100% (6 PR, 1 NE) compared with DKK1 low pts (n=9) ORR of 56% (5 PR, 4 SD). Median DoR and PFS were not reached. Conclusions D + T + CAPOX was well tolerated and has encouraging early activity as first line treatment for advanced GEA (unselected for PD-L1), with a preliminary ORR of 68% and DCR of 100%. Higher ORR in biomarker RE population: DKK1 high compared with DKK1 low (ORR 100% vs 56%). Updated ORR, DoR, PFS and PD-L1 expression will be reported.

Dickkopf-1 (DKK1) is a Wnt signaling modulator promoting tumor growth, metastasis, angiogenesis, and immunosuppression by regulating innate immunity. DKK1 is over-expressed in gynecologic cancers and is associated with shortened survival. DKN-01 is a humanized monoclonal antibody with DKK1 neutralizing activity that may provide clinical benefit to patients whose tumors have overexpression of DKK1 or Wnt genetic alterations.We conducted an open-label, Phase 2 basket study with 2-stage design in patients with endometrial carcinoma (EC) and platinum-resistant/refractory epithelial ovarian cancer. DKN-01 was administered either as monotherapy or in combination with weekly paclitaxel at investigator's discretion. All patients underwent NGS testing prior to enrollment; tumor tissue was also tested for DKK1 expression by RNAscope pre-treatment and after cycle 1 if available. At least 50% of patients were required to have a Wnt signaling alteration either directly or tangentially. This publication reports results from the EC population overall and by DKK1-expression.DKN-01 monotherapy and in combination with paclitaxel was more effective in patients with high DKK1-expressing tumors compared to low-expressing tumors. DKN-01 monotherapy demonstrated an objective response rate [ORR] of 25.0% vs. 0%; disease control rate [DCR] of 62.5% vs. 6.7%; median progression-free survival [PFS] was 4.3 vs. 1.8 months, and overall survival [OS] was 11.0 vs. 8.2 months in DKK1-high vs DKK1-low patients. Similarly, DKN-01 in combination with paclitaxel demonstrated greater clinical activity in patients with DKK1-high tumors compared to DKK1-low tumors: DCR was 55% vs. 44%; median PFS was 5.4 vs. 1.8 months; and OS was 19.1 vs. 10.1 months. Wnt activating mutations correlated with higher DKK1 expression. DKN-01 was well tolerated as a monotherapy and in combination with paclitaxel.Collectively, data demonstrates promising clinical activity of a well-tolerated drug, DKN-01, in EC patients with high tumoral DKK1 expression which frequently corresponded to the presence of a Wnt activating mutation. Future development will focus on using DKN-01 in DKK1-high EC patients in combination with immunotherapy.

Targeted therapies are being increasingly used in clinical practice and trials. However, tumor heterogeneity among sites of metastatic disease can occur creating a conundrum when utilizing biomarker directed therapies. Here we demonstrate a patient with recurrent uterine carcinosarcoma whose local recurrence and metastatic recurrence had a varied response to paclitaxel in combination with DKN-01, a monoclonal antibody against DKK1, a modulator of Wnt/β-catenin and PI3K/AKT signaling pathways. This may be explained by differences in mutational profile found between the two sites. Our findings highlight the importance of analyzing tissue from the primary tumor as well as metastatic lesions, especially if there is a discrepancy in their response to treatment.

Up-regulation of the long non-coding RNA LINC00152 can contribute to cancer development, proliferation and invasion, including colorectal cancer, however, its mechanism of action in colorectal carcinogenesis and progression is only insufficiently understood. In this work we correlated LINC00152 expression with promoter DNA methylation changes in colorectal tissues along the normal-adenoma-carcinoma sequence and studied the effects of LINC00152 silencing on the cell cycle regulation and on the whole transcriptome in colon carcinoma cells using cell and molecular biology techniques. LINC00152 was significantly up-regulated in adenoma and colorectal cancer (p?