Search

Plasma circulating tumor DNA (ctDNA) sequencing has demonstrated clinical utility for tumor molecular profiling at initial diagnosis or tumor progression in advanced solid cancers and is being rapidly incorporated into the clinical practice guidelines, including non–small cell lung and breast cancer. Despite relatively low sensitivity, plasma ctDNA sequencing has several advantages over tissue-based assays, including ease of sampling, rapid turnaround time, repeatability, and the ability to overcome spatial heterogeneity, which makes it ideal for investigating acquired resistance and monitoring tumor evolution and dynamics. With technological advancement and declining costs, the clinical application of plasma ctDNA is expanding, and numerous ongoing clinical trials are examining its potential to guide the management of advanced, localized, and even preclinical cancers of various tumor types. The ability of plasma ctDNA analysis to detect minimal residual disease following curative treatment in the absence of clinical disease is among its most promising attributes. Plasma ctDNA sequencing can also facilitate the conduct of clinical trials and drug development, particularly in immunotherapy. In order to incorporate plasma ctDNA sequencing for clinical decision-making, it is important to understand the preanalytical and analytical factors that may affect its sensitivity and reliability.

PURPOSE The combination of oxaliplatin and fluoropyrimidine for 6 months is one of the standard options for adjuvant therapy for high-risk stage II and III colorectal cancers (CRCs). The optimal duration of oxaliplatin to diminish neurotoxicity without compromising efficacy needs to be clarified. PATIENTS AND METHODS This open-label, randomized, phase III, noninferiority trial randomly assigned patients with high-risk stage II and III CRC to 3 and 6 months of oxaliplatin with 6 months of fluoropyrimidine groups (3- and 6-month arms, respectively). The primary end point was disease-free survival (DFS), and the noninferiority margin was a hazard ratio (HR) of 1.25. RESULTS In total, 1,788 patients were randomly assigned to the 6-month (n = 895) and 3-month (n = 893) arms, and 83.6% in the 6-month arm and 85.7% in the 3-month arm completed the treatment. The neuropathy rates with any grade were higher in the 6-month arm than in the 3-month arm (69.5% v 58.3%; P < .0001). The 3-year DFS rates were 83.7% and 84.7% in the 6-month and 3-month arms, respectively, with an HR of 0.953 (95% CI, 0.769 to 1.180; test for noninferiority, P = .0065) within the noninferiority margin. Among patients with stage III CRC treated by capecitabine plus oxaliplatin, the 3-year DFS of the 3-month arm was noninferior as compared with that of the 6-month arm with an HR of 0.713 (95% CI, 0.530 to 0.959; P = .0009). However, among patients with high-risk stage II and stage III CRC treated by infusional fluorouracil, leucovorin, and oxaliplatin, the noninferiority of the 3-month arm compared with the 6-month arm was not proven. CONCLUSION This study suggests that adding 3 months of oxaliplatin to 6 months of capecitabine could be considered an alternative adjuvant treatment for stage III CRC (ClinicalTrials.gov identifier: NCT01092481 ).

BACKGROUND: Circulating tumour DNA (ctDNA) has been spotlighted as an attractive biomarker because of its easy accessibility and real-time representation of tumour genetic profile. However, the clinical utility of longitudinal ctDNA monitoring has not been clearly defined. METHODS: Serial blood samples were obtained from metastatic colorectal cancer patients undergoing first-line chemotherapy. ctDNA was sequenced using a targeted next-generation sequencing platform which included 106 genes. Changes in ctDNA profile and treatment outcome were comprehensively analysed. RESULTS: A total of 272 samples from 62 patients were analysed. In all, 90.3% of patients had detectable ctDNA mutation before treatment. ctDNA clearance after chemotherapy was associated with longer progression-free survival which was independent of radiological response (adjusted hazard ratio 0.22, 95% confidence interval 0.10–0.46). Longitudinal monitoring was able to detect ctDNA progression which preceded radiological progressive disease (PD) in 58.1% (median 3.3 months). Diverse resistant mutations (34.9%) and gene amplification (7.0%) at the time of PD were discovered. For 16.3% of the PD patients, the newly identified mutations could be potential candidates of targeted therapy or clinical trial. CONCLUSION: ctDNA profile provided a more accurate landscape of tumour and dynamic changes compared to radiological evaluation. Longitudinal ctDNA monitoring may improve personalised treatment decision-making.

PurposeWe aimed to assess the real-world efficacy of nab-paclitaxel in metastatic breast cancer patients.Materials and MethodsThis is a retrospective study performed in two tertiary referral hospitals in Korea. Patients with metastatic breast cancer treated with nab-paclitaxel (Abraxane®) between March 2016 and March 2020 were enrolled.ResultsA total of 102 patients with metastatic breast cancer were included. Patients were heavily pre-treated with a median of four prior lines of chemotherapy (5 lines when including endocrine therapy in hormone-receptor-positive patients), and 66 patients (64.7%) were exposed to taxanes in the metastatic setting. According to St. Gallen molecular subtypes, 36 patients (35.3%) were luminal A, 28 (27.5%) were luminal B, 18 (17.7%) were human epidermal growth factor receptor 2–positive and 20 (19.6%) had triple-negative disease. Fifty patients (49.0%) were treated with a 3-weekly regimen (260 mg/m2 on day 1 every 3 weeks), and 52 (51.0%) were treated with a weekly regimen (100 mg/m2 every week). Objective response rate was 22.9%. After a median follow-up of 22.0 months, median progression-free survival (PFS) was 4.0 months (95% confidence interval [CI], 2.6 to 4.8) and median overall survival was 8.7 months (95% CI, 7.5 to 11.2). Patients treated with weekly regimen had longer PFS compared to 3-weekly regimen (5.5 vs. 2.3 months, p < 0.001). Multivariate analysis revealed the treatment regimen as an independent prognostic factor for PFS. There was no grade 3 or 4 hypersensitivity reaction.ConclusionThis real-world data shows that nab-paclitaxel is a reasonable treatment option in heavily pre-treated and/or taxane-exposed metastatic breast cancer patients.

Immune-stimulator antibody conjugates (ISAC) combining tumor-targeting monoclonal antibodies with immunostimulatory agents allow targeted delivery of immune activators into tumors. NJH395 is a novel, first-in-class ISAC comprising a Toll‐like receptor 7 (TLR7) agonist conjugated to an anti-HER2 antibody via a noncleavable linker payload. Preclinical characterization showed ISAC-mediated activation of myeloid cells in the presence of antigen-expressing cancer cells, with antigen targeting and TLR7 agonism contributing to antitumor activity. Safety, efficacy, immunogenicity, pharmacokinetics, and pharmacodynamics were investigated in a phase I, multicenter, open-label study in patients with HER2+ non-breast advanced malignancies (NCT03696771). Data from 18 patients enrolled in single ascending dose escalation demonstrated delivery of the TLR7-agonist payload in HER2+ tumor cells and induction of type I IFN responses, which correlated with immune modulation in the tumor microenvironment. Cytokine release syndrome was a common, but manageable, drug-related adverse event. Antidrug antibodies and neuroinflammation at high doses represented significant clinical challenges. Data provide proof-of-mechanism and critical insights for novel immunotherapies.

Supplementary Figure from Preclinical Characterization and Phase I Study of an Anti–HER2-TLR7 Immune-Stimulator Antibody Conjugate in Patients with HER2+ Malignancies

Supplementary Data from Preclinical Characterization and Phase I Study of an Anti–HER2-TLR7 Immune-Stimulator Antibody Conjugate in Patients with HER2+ Malignancies

PDF file - 114K, Chemical structures of investigated molecules in this article

PDF file - 135K, Treatment of saracatinib in LS174T and SKBR3 cells

PDF file - 176K

PDF file - 335K

PDF file - 173K, Induction of Bim by saracatinib treatment

A PARP inhibitor is a rationally designed targeted therapy for cancers with impaired DNA repair abilities. RAD51C is a paralog of RAD51 that has an important role in the DNA damage response. We found that cell lines sensitive to a novel oral PARP inhibitor, olaparib, had low levels of RAD51C expression using microarray analysis, and we therefore hypothesized that low expression of RAD51C may hamper the DNA repair process, resulting in increased sensitivity to olaparib. Compared with the cells with normal RAD51C expression levels, RAD51C-deficient cancer cells were more sensitive to olaparib, and a higher proportion underwent cell death by inducing G2–M cell-cycle arrest and apoptosis. The restoration of RAD51C in a sensitive cell line caused attenuation of olaparib sensitivity. In contrast, silencing of RAD51C in a resistant cell line enhanced the sensitivity to olaparib, and the number of RAD51 foci decreased with ablated RAD51C expression. We also found the expression of RAD51C was downregulated in cancer cells due to epigenetic changes and RAD51C expression was low in some gastric cancer tissues. Furthermore, olaparib significantly suppressed RAD51C-deficient tumor growth in a xenograft model. In summary, RAD51C-deficient cancer cells are highly sensitive to olaparib and offer preclinical proof-of-principle that RAD51C deficiency may be considered a biomarker for predicting the antitumor effects of olaparib. Mol Cancer Ther; 12(6); 865–77. ©2013 AACR.

Supplementary Table 1. The IC50 values of bosutinib, gemcitabine, and cisplatin in biliary tract cancer cell lines.

PDF file - 96K, Downregulation of thymidylate synthase (TS) by saracatinib

PDF file - 103K

PDF file - 3250K, Figure S1 Olaparib has variable levels of anti-tumor activity in human cancer cell lines. Figure S2 Olaparib sensitive cell lines have different patterns of gene expression compared to insensitive cell lines. Figure S3 PTEN expression does not affect olaparib sensitivity. Figure S4 RAD51C expression affects olaparib sensitivity in human cancer cell lines. Figure S5 RAD51C over-expression decreases sensitivity to olaparib in the BT-549 cell line. Figure S6 Olaparib induces G2/M cell cycle arrest and apoptosis in sensitive cell lines. Figure S7 RAD51C depletion increases the accumulation of DNA damage. Figure S8 RAD51C expression decreases in tumor tissues. Figure S9 RAD51C expression is down-regulated in gastric tumor tissues via DNA methylation. Table S1. Sequences of the primers for PCR and real-time PCR analyses. Table S2. BRCA1 and BRCA2 mutations in the gastric cancer cell lines.

PDF file - 215K, mRNA and protein expression level of integrin �8 in gastric cancer cell lines

To evaluate the safety and effectiveness of aflibercept in combination with fluorouracil, leucovorin, and irinotecan (FOLFIRI) in Korean patients with metastatic colorectal cancer (mCRC) who progressed with oxaliplatin-containing regimen.This was a prospective observational study conducted at 22 sites across Korea between February 2018 and September 2019. Patients aged 19 years with a diagnosis of mCRC who were prescribed aflibercept plus FOLFIRI, after progression with an oxaliplatin-containing regimen were included. Disease assessment was performed every 6 weeks.A total of 185 patients were included (males, 58.9%; right-sided tumors, 23.8%; and ECOG performance factor ≥ 1, 68.6%). A total of 514 adverse events (AEs) occurred in 134 patients, of which 206 (49.2%; 95% CI 42.0%, 56.4%) events were considered as adverse drug reactions (ADRs), 172 unexpected AEs (49.7%; 95% CI 42.5%, 56.9%), and 53 serious AEs (22.2%; 95% CI16.2%, 28.2%). The most common serious ADR was pneumonia (n = 2, 1.6%). The most common all grade hematological AE and non-hematological AE were neutropenia (21.6%) and nausea (16.2%), respectively. Over a median follow-up of 5.6 months, a total of five grade 5 (1.0%) AEs were reported. Median OS was 9.4 months, and median progression-free survival (PFS) was 7.3 months. The overall response rate was 14.6%. Right-sided tumor location and prior bevacizumab treatment were independent factors of poor PFS in multivariate analysis.Aflibercept in combination with FOLFIRI was effective and showed an acceptable safety profile in Korean patients with mCRC in daily clinical practice.

Lymphatic invasion, vascular invasion, and perineural invasion are prognostic factors for colon cancer. However, the prognostic significance of those factors according to the location of permeation (intramural and extramural invasion) in stage II colon cancer is still unclear.This study aims to clarify whether the location of lymphatic invasion, vascular invasion, and perineural invasion could affect survival of stage II colon cancer patients.This was a retrospective cohort study.This study took place at a university teaching hospital.A total of 1130 patients with stage II colon cancers who underwent radical surgery at the Seoul National University Hospital between July 2003 and December 2015 were included.Patients were classified according to the location of lymphatic invasion, vascular invasion, and perineural invasion. Survival outcomes were compared among those without invasion, and those with intramural and extramural invasion. Primary end point is overall survival and secondary end point is disease free survival.Disease-free survival and overall survival of patients with extramural invasion were worse than those of patients without invasion and those with intramural invasion. Multivariate analysis for survival outcomes confirmed that extramural invasion were significant independent prognostic factors. However, both disease free survival and overall survival were not significantly different between patients without invasion and those with intramural invasion.This study was limited by its retrospective design.Extramural invasion was associated with worse prognosis in stage II colon cancer, but intramural invasion was not. Therefore, pathologic reports about the location of lymphatic invasion, vascular invasion, and perineural invasion might be helpful for predicting prognosis and for determining the need of adjuvant chemotherapy in stage II colon cancers. See Video Abstract at http://links.lww.com/DCR/B939.

Background Sotorasib, a specific, irreversible KRAS(G12C) protein inhibitor, has shown monotherapy clinical activity in KRAS(G12C)-mutated solid tumours, including colorectal cancer, in the CodeBreaK100 phase 1 trial. We aimed to investigate the activity and safety of sotorasib in phase 2 of the trial. Methods In this single-arm, phase 2 trial, adult patients with KRAS(G12C)-mutated advanced solid tumours were enrolled, from 59 medical centres in 11 countries, if they were aged 18 years or older, had at least one measurable lesion according to the Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1, and had an Eastern Cooperative Oncology Group performance status of 1 or lower. Only data for patients with colorectal cancer, enrolled at 33 medical centres in nine countries, are presented from this basket trial. To be enrolled, the patients had to have progressed after receiving fluoropyrimidine, oxaliplatin, and irinotecan treatment. These patients were administered 960 mg sotorasib orally once per day until disease progression, development of unacceptable side-effects, withdrawal of consent, or death. The primary endpoint was objective response (complete or partial response) as assessed by blinded independent central review. Response was evaluated in patients who received at least one dose of sotorasib and had at least one measurable lesion at baseline; safety was evaluated in patients who received at least one dose of sotorasib. This analysis is a prespecified analysis triggered by the phase 2 colorectal cancer cohort. This study is registered with ClinicalTrials.gov, NCT03600883, and is active but no longer recruiting. Findings On March 1, 2021, at data cutoff, 62 patients with KRAS(G12C)-mutant colorectal cancer had been enrolled between Aug 14, 2019, and May 21, 2020, and had received at least one dose of sotorasib monotherapy. Objective response was observed in six (9.7%, 95% CI 3.6-19.9) of 62 patients, all with partial response. Treatment-related adverse events at grade 3 occurred in six (10%) patients, the most common of which was diarrhoea (two [3%] of 62 patients), and at grade 4 occurred in one (2%) patient (blood creatine phosphokinase increase); no fatal events were recorded. Serious treatment-related adverse events occurred in two (3%) patients (back pain and acute kidney injury). Interpretation Although the 9.7% overall response rate did not reach the benchmark, oral administration of sotorasib once per day showed modest anti-tumour activity and manageable safety in these heavily pretreated chemorefractory patients. Sotorasib is under evaluation in combination with other therapeutics to increase potential activity and overcome potential resistance mechanisms.

Supplementary Table 7: Next-generation sequencing of tumor biopsy samples (see separate Excel file) Supplementary Table 8: Copy number variations for patients with tumor biopsy samples available (see separate Excel file) Supplementary Table 9: Summary of copy number variations as assessed by polymerase chain reaction (see separate Excel file)

Supplementary Tables 1-2. Table S1. HER2/CEP17 ratio and HER2 gene copy number by HER2 IHC; Table S2: Univariateand multivariate Cox analysis of overall survival

Prognostic role of tumor mutation burden (TMB) stratified by microsatellite instability (MSI) status.

EGFR tyrosine kinase inhibitors have shown promising efficacy in the treatment of tumors with EGFR mutations and amplifications. However, tyrosine kinase inhibitors have also proven ineffective against most tumors with EGFR wild-type (WT) alleles. Although some genetic changes, including the KRAS mutation, have been shown to confer resistance to tyrosine kinase inhibitors, novel strategies for the treatment of cancer patients with tumors harboring EGFR WT alleles have yet to be thoroughly delineated. The principal objective of this study was to improve our current understanding of drug interactions between EGFR and MAP/ERK kinase (MEK) inhibitors in an effort to gain insight into a novel therapeutic strategy against EGFR WT tumors. Using a panel of human EGFR WT gastric cancer cell lines, we showed that gastric cancer cells harboring the KRAS mutation were selectively sensitive to MEK inhibition as compared with those cells harboring KRAS and PI3K mutations and KRAS WT alleles. However, all cell lines were found to be resistant to EGFR inhibition. The results from Western blots and phosphoprotein arrays showed that, in MEK inhibitor resistant cell lines, AKT was activated through the EGFR/HER3/PI3K pathway following AZD6244 (ARRY-142886) treatment. Blockade of this feedback mechanism through the targeting of MEK and EGFR resulted in detectable synergistic effects in some cell lines in vitro and in vivo. Our results provide the basis for a rational combination strategy against human EGFR WT gastric cancers, predicated on the understanding of cross-talk between the MEK and EGFR pathways. [Mol Cancer Ther 2009;8(9):2526–36]

Supplementary Figure 1: Study design

Supplementary Data from Combination of EGFR and MEK1/2 inhibitor shows synergistic effects by suppressing EGFR/HER3-dependent AKT activation in human gastric cancer cells

Purpose:Recent sequencing studies revealed that a subset of colorectal cancer harbors a significantly higher number of somatic mutations. These hypermutated tumors show distinct clinicopathologic features. However, the prognostic impact of the hypermutated tumors is not clearly established.Experimental Design:We analyzed tumor mutation burden (TMB) from targeted next-generation sequencing data of 40 major genes in 516 patients with colorectal cancer. TMB was defined as total number of nonsynonymous mutations per tumor. Cutoff value for TMB-high was chosen by which best discriminated relapse-free survival (RFS) using the Contal and O'Quigley method.Results:In the TCGA data, mutation count of the selected 40 genes reflected the whole exome mutation burden (Pearson correlation = 0.873, P < 0.001). In our patient cohort, 8 or more mutations in the 40 genes was defined as TMB-high, which best discriminated RFS. A total of 55 patients (10.7%) had TMB-high. TMB-high tumors were more frequently found in a proximal location (63.6%) and had a higher proportion of N0 disease (30.9%) and MSI-H (49.1%) compared with TMB-low. Most importantly, TMB-high was associated with better 5-year RFS compared with TMB-low (96.3% vs. 79.8%, P = 0.005). Although there was significant overlap between TMB-high and MSI-H, MSI-H status was not significantly associated with RFS. Multivariate analysis revealed TMB-high as an independent positive prognostic factor for RFS [adjusted HR, 0.16 (95% confidence interval, 0.04–0.66), P = 0.011].Conclusions:TMB-high is associated with better prognosis in patients with colorectal cancer treated with curative surgery followed by adjuvant fluoropyrimidine and oxaliplatin chemotherapy.

Supplementary Figure 2. Representative images of HER2 IHC and HER2 FISH

Supplementary Figure 3: Glucose and insulin levels after treatment with GSK2636771 in fasted mice.

Purpose:Despite the well-known prognostic value of the tumor–immune microenvironment (TIME) in colorectal cancers, objective and readily applicable methods for quantifying tumor-infiltrating lymphocytes (TIL) and the tumor–stroma ratio (TSR) are not yet available.Experimental Design:We established an open-source software-based analytic pipeline for quantifying TILs and the TSR from whole-slide images obtained after CD3 and CD8 IHC staining. Using a random forest classifier, the method separately quantified intraepithelial TILs (iTIL) and stromal TILs (sTIL). We applied this method to discovery and validation cohorts of 578 and 283 stage III or high-risk stage II colorectal cancers patients, respectively, who were subjected to curative surgical resection and oxlaliplatin-based adjuvant chemotherapy.Results:Automatic quantification of iTILs and sTILs showed a moderate concordance with that obtained after visual inspection by a pathologist. The K-means–based consensus clustering of 197 TIME parameters that showed robustness against interobserver variations caused colorectal cancers to be grouped into five distinctive subgroups, reminiscent of those for consensus molecular subtypes (CMS1-4 and mixed/intermediate group). In accordance with the original CMS report, the CMS4-like subgroup (cluster 4) was significantly associated with a worse 5-year relapse-free survival and proved to be an independent prognostic factor. The clinicopathologic and prognostic features of the TIME subgroups have been validated in an independent validation cohort.Conclusions:Machine-learning–based image analysis can be useful for extracting quantitative information about the TIME, using whole-slide histopathologic images. This information can classify colorectal cancers into clinicopathologically relevant subgroups without performing a molecular analysis of the tumors.

Background: The PI3K/protein kinase B (AKT) pathway is commonly activated in several tumor types. Selective targeting of p110β could result in successful pathway inhibition while avoiding the on- and off-target effects of pan-PI3K inhibitors. GSK2636771 is a potent, orally bioavailable, adenosine triphosphate-competitive, selective inhibitor of PI3Kβ.Methods: We evaluated the safety, pharmacokinetics, pharmacodynamics and antitumor activity of GSK2636771 to define the recommended phase II dose (RP2D). During the dose-selection and dose-escalation stages (parts 1 and 2), patients with PTEN-deficient advanced solid tumors received escalating doses of GSK2636771 (25–500 mg once daily) using a modified 3+3 design to determine the RP2D; tumor type-specific expansion cohorts (part 3) were implemented to further assess tumor responses at the RP2D.Results: A total of 65 patients were enrolled; dose-limiting toxicities were hypophosphatemia and hypocalcemia. Adverse events included diarrhea (48%), nausea (40%), and vomiting (31%). Single- and repeat-dose exposure increased generally dose proportionally. GSK2636771 400 mg once daily was the RP2D. Phospho/total AKT ratio decreased with GSK2636771 in tumor and surrogate tissue. A castrate-resistant prostate cancer (CRPC) patient harboring PIK3CB amplification had a partial response for over a year; an additional 10 patients derived durable (≥24 weeks) clinical benefit, including two other patients with CRPC with PIK3CB alterations (≥34 weeks). GSK2636771 400 mg once daily orally induced sufficient exposure and target inhibition with a manageable safety profile.Conclusions: Genomic aberrations of PIK3CB may be associated with clinical benefit from GSK2636771. Clin Cancer Res; 23(19); 5981–92. ©2017 AACR.

Supplementary Figure 1. CONSORT diagram

Supplementary Table 1: 3 + 3 dose escalation guidelines Supplementary Table 2: Customized sequencing panel Supplementary Table 3: Summary of AEs occurring in >20% of all patients, treatment-related AEs and SAEs Supplementary Table 4: PK parameters following single dose oral dosing of GSK2636771 (PK population) Supplementary Table 5: PK parameters following single daily oral dosing of GSK2636771 (PK population) Supplementary Table 6: PK parameters following multiple dose oral dosing of GSK2636771 (PK population)