Antibodies In Colorectal Cancer Research Articles

Fumarate Hydratase Enhances the Therapeutic Effect of PD-1 Antibody in Colorectal Cancer by Regulating PCSK9.

Despite the notable achievements of programmed death 1 (PD-1) antibodies in treating various cancers, the overall efficacy remains limited in the majority of colorectal cancer (CRC) cases. Metabolism reprogramming of tumors inhibits the tricarboxylic acid (TCA) cycle, leading to down-regulation of fumarate hydratase (FH), which is related to poor prognosis in CRC patients. By establishing a tumor-bearing mouse model of CRC with Fh1 expression deficiency, we confirmed that the therapeutic effect of PD-1 antibodies alone was suboptimal in mice with low Fh1 expression, which was improved by combination with a protein invertase subtilisin/kexin 9 (PCSK9) inhibitor. Mechanistically, FH binds to Ras-related nucleoprotein (RAN), which inhibits the nuclear import of the PCSK9 transcription factor SREBF1/2, thus reducing the expression of PCSK9. This leads to increased clonal expansion of CD8+ T cells while the number of Tregs remains unchanged, and the expression of PD-L1 does not change significantly, thus enhancing the immunotherapy response. On the contrary, the expression of PCSK9 increased in CRC cells with low FH expression, which antagonized the effects of immunotherapy. Overall, CRC patients with low FH expression may benefit from combinatorial therapy with PD-1 antibodies and PCSK9 inhibitors to enhance the curative effect.

The role of intestinal flora on tumorigenesis, progression, and the efficacy of PD-1/PD-L1 antibodies in colorectal cancer.

Intestinal flora affects the maturation of the host immune system, serves as a biomarker and efficacy predictor in the immunotherapy of several cancers, and has an important role in the development of colorectal cancer (CRC). Anti-PD-1/PD-L1 antibodies have shown satisfactory results in MSI-H/dMMR CRC but performed poorly in patients with MSS/pMMR CRC. In recent years an increasing number of studies have shown that intestinal flora has an important impact on anti-PD-1/PD-L1 antibody efficacy in CRC patients. Preclinical and clinical evidence have suggested that anti-PD-1/PD-L1 antibody efficacy can be improved by altering the composition of the intestinal flora in CRC. Herein, we summarize the studies related to the influence of intestinal flora on anti-PD-1/PD-L1 antibody efficacy in CRC and discuss the potential underlying mechanism(s). We have focused on the impact of the intestinal flora on the efficacy and safety of anti-PD-1/PD-L1 antibodies in CRC and how to better utilize the intestinal flora as an adjuvant to improve the efficacy of anti-PD-1/PD-L1 antibodies. In addition, we have provided a basis for the potential of the intestinal flora as a new treatment modality and indicator for determining patient prognosis.

P-131 - Evaluating the radionuclide theranostic potential of a MUC13-targeting antibody in colorectal cancer

P-131 - Evaluating the radionuclide theranostic potential of a MUC13-targeting antibody in colorectal cancer

CfDNA NGS detection of fusions acquired as mechanisms of resistance in the post-EGFR setting across multiple solid tumors.

3053 Background: Oncogenic fusions are rare but have targetable, FDA-approved therapies across all solid tumor types. These fusions have been associated with resistance to EGFR-TKI (EGFRi) in advanced non-small cell lung cancer (NSCLC) and anti-EGFR antibodies in colorectal cancer (CRC), but the prevalence of acquired fusions and their associated clinical outcomes have not been well-studied. We examined fusions in >5,000 patients with advanced NSCLC or CRC who had a history of EGFR-directed therapy in the GuardantINFORM clinical-genomic database. Methods: Fusions in ALK, FGFR1-3, NTRK1-3, ROS1 and RET were examined in a cohort of 2,379 patients with NSCLC and 1,072 with CRC tested with Guardant360 or Guardant360 CDx (Guardant Health, Redwood City, CA) before approved EGFR-targeting therapies, and in 3,531 patients with NSCLC and 2,132 patients with CRC tested after EGFR therapy. Fusion clonality was calculated as the fusion variant allele fraction (VAF):max somatic VAF for each patient, with subclonal fusions defined as having clonality < 0.5. Clinical outcomes were compared between patients with and without fusions in the post-EGFR population, adjusting for age, gender, regimen/line of therapy, and max VAF. Comparisons of fusion prevalence pre- and post-EGFR therapy were performed using Fisher’s exact test. Results: Fusions were detected more frequently in patients with NSCLC and CRC after EGFR therapy relative to pretreatment (NSCLC: 3.2% vs. pre-EGFR 0.5%, p<0.05; CRC: 6.4% vs. pre-EGFR 1.1%, p<0.05). Fusions in RET were most enriched in the post-EGFR NSCLC population (1.0% vs. pre-EGFR 0.1%, OR=11.6, p<0.05), while fusions in the FGFR family were most enriched in the post-EGFR CRC population (3.0% vs. pre-EGFR 0.3%, OR=10.8, p<0.05). The majority of fusions post-EGFR were subclonal in patients with NSCLC (86%) and CRC (96%), consistent with these fusions emerging as mechanisms of resistance. In patients with NSCLC, clinical outcomes (as measured by time-to-next-treatment (TTNT)) were significantly shorter in patients who acquired fusions compared to those without fusions (median 5.9 vs. 9.5 months, log-rank p=0.01, adjusted HR=1.7, adjusted p=0.02). Patients with CRC showed no significant difference in TTNT between those with and without acquired fusions. In patients with NSCLC who acquired fusions, 45% received an EGFRi in the next line and 23% received a TKI targeted to their fusion; TTNT on these therapies was not significantly different (median 5.3 months vs. 6.4 months, respectively). Conclusions: Fusions in patients with NSCLC and CRC were enriched post-EGFR therapy and were associated with inferior clinical outcomes in NSCLC. Recognition of the subclonal prevalence of acquired fusions provides important context as oncologists consider the next line of therapy. This work highlights the potential utility of genomic profiling in patients over the course of treatment.

Prognostic and diagnostic significance of preoperative Jumonji domain‑containing 6 antibodies in colorectal cancer.

Jumonji domain-containing 6 (JMJD6) protein has been reported to be upregulated in different cancer cells; however, to the best of our knowledge, no report has analyzed serum anti-JMJD6 antibodies (s-JMJD6-Abs) in patients with cancer. Therefore, the present study evaluated the clinical significance of s-JMJD6-Abs in patients with colorectal cancer. Preoperative serum samples were analyzed from 167 patients with colorectal cancer who underwent radical surgery between April 2007 and May 2012. The pathological stages were as follows Stage I (n=47), stage II (n=56), stage III (n=49) and stage IV (n=15). In addition, 96 healthy participants were analyzed as controls. s-JMJD6-Abs were analyzed by amplified luminescent proximity homology assay-linked immunosorbent assay. The cutoff value of s-JMJD6-Abs for detecting colorectal cancer was calculated to be 5,720 using the receiver operating characteristic curve. The positive rate of s-JMJD6-Abs was 37% in patients with colorectal cancer (61 of 167), independent of carcinoembryonic antigen or carbohydrate antigen 19-9 and p53-Abs. Clinicopathological factors and prognosis were compared between the s-JMJD6-Abs-positive group and the s-JMJD6-Abs-negative group. The s-JMJD6-Ab-positive status was significantly associated with older age (P=0.03), but was not associated with other clinicopathological variables. Regarding recurrence-free survival, the s-JMJD6-positive status was a significant poor prognostic factor in both univariate (P=0.02) and multivariate (P<0.01) analyses. Similarly, regarding overall survival, the s-JMJD6-Abs-positive status was a significant poor prognostic factor in both univariate (P=0.03) and multivariate (P=0.01) analyses. In conclusion, preoperative s-JMJD6-Abs was positive in 37% of patients with colorectal cancer and may be considered an independent poor prognostic biomarker.

The Sesquiterpene Lactone-Rich Fraction of Inula helenium L. Enhances the Antitumor Effect of Anti-PD-1 Antibody in Colorectal Cancer: Integrative Phytochemical, Transcriptomic, and Experimental Analyses.

Treatment strategies combining immune checkpoint inhibitors with sesquiterpene lactones have attracted much attention as a promising approach for cancer treatment. We systemically analyzed gene expression profiles of cells in response to two major sesquiterpene lactones, alantolactone and isoalantolactone, and determined whether the sesquiterpene lactone-rich fraction of Inula helenium L. (SFIH) enhances the antitumor effect of anti-PD-1 antibody in MC38 colorectal cancer-bearing mice. Gene expression and pathway analysis using RNA sequencing data were used to identify the SFIH-driven combined activity with anti-PD-1 antibody. The results showed that SFIH significantly enhanced the antitumor effect of anti-PD-1 antibody by reducing tumor growth and increasing the survival time of mice. Specifically, SFIH exhibited antitumor activity when combined with anti-PD-1 antibody, and the effects were further enhanced compared with monotherapy. An analysis of immune cells indicated that combination treatment with SFIH and anti-PD-1 antibody significantly increased the proportion of CD8+ T cells. Moreover, combination treatment enhanced antitumor immunity by decreasing the population of myeloid-derived suppressor cells and increasing the number of M1-like macrophages. Pathway enrichment analysis revealed that combination therapy activated immune-related pathways to a greater extent than monotherapy. In conclusion, our integrative analysis demonstrates that SFIH enhances the response of murine tumors to anti-PD-1 antibody. These findings provide insight into developing integrative therapeutics and molecular data for the use of natural products as an adjunct treatment for colorectal cancer.

KRAS mutation as a predictor of insufficient trastuzumab efficacy and poor prognosis in HER2-positive advanced gastric cancer.

Although RAS and PIK3CA mutations have been associated with resistance to anti-EGFR antibody in colorectal cancer or trastuzumab in breast cancer, their implications for trastuzumab resistance in HER2-positive advanced gastric cancer (AGC) remains unclear. We aimed to assess the relationship between trastuzumab efficacy and mutation status in the HER family signaling pathway. This study retrospectively evaluated patients with HER2-positive AGC who received first-line trastuzumab-containing chemotherapy between March 2011 and November 2015. Multiplex genotyping, including KRAS, NRAS, PIK3CA, and BRAF, was then performed using the Luminex Assay, after which KRAS amplification was measured using quantitative real-time reverse transcription-polymerase chain reaction. Thereafter, the association between genetic alterations and clinical outcomes were evaluated. KRAS mutation (MT) was detected in 6 of 77 patients (7.8%), whereas KRAS amplification was found in 15 of 67 patients (22%). No mutations in NRAS, PIK3CA, or BRAF were identified. The KRAS MT group showed significantly worse response rates (16.7% vs. 66.2%, P = 0.016), progression-free survival [median, 4.8 vs. 11.6months; hazard ratio (HR), 3.95; 95% CI, 1.60-9.76; P = 0.0029], and overall survival (11.5 vs. 23.6months; HR, 3.80; 95% CI, 1.56-9.28; P = 0.033) compared to the KRAS wild-type group. KRAS amplification had no effect on clinical outcomes. KRAS mutation was an independent prognostic factor for poor survival and might predict insufficient trastuzumab efficacy, whereas KRAS amplification showed no prognostic significance during trastuzumab treatment. Further investigations are warranted to confirm the predictive value of KRAS status in HER2-positive AGC.

Photothermal-Chemotherapy Enhancing Tumor Immunotherapy by Multifunctional Metal-Organic Framework Based Drug Delivery System.

Immunotherapy holds great promise for patients undergoing tumor treatment. However, the clinical effect of immunotherapy is limited because of tumor immunogenicity and its immunosuppressive microenvironment. Herein, the metal-organic framework (MIL-100) loaded with chemotherapeutic agent mitoxantrone (MTO) was combined with photothermal-chemotherapy for enhancing immunogenic cell death. MIL-100 loaded with MTO and hyaluronic acid as nanoparticles (MMH NPs) yielded an NP with two therapeutic properties (photothermal and chemotherapy) with dual imaging modes (photoacoustic and thermal). When MMH NPs were coinjected with an anti-OX40 antibody in colorectal cancer, the highest antitumor efficacy and a robust immune effect were achieved. This work provides a novel combined therapeutic strategy, which will hold great promise in future tumor therapy.

Serum anti-laminarin antibodies in colorectal cancer: a prospective pilot study

ntroduction and objectives: Laminarin is a low molecular weight (504 Da) glucose branched polysaccharide which modulates humoral and cellular immune response, both non-specific and specific. Laminarin possesses anti-tumorous activity as it induces apoptosis and modulates the colonic microbio­ta. The aim of our current study was to evaluate anti-laminarin antibodies in colorectal carcinoma. Methods: A total of 46 individuals were enrolled in the prospective study including 14 controls (5 men, 9 women, age 29–80, mean 55 ± 13) and 32 patients with colorectal carcinoma, CRC (14 men, 18 women, age 46–86, mean 66 ± 11). Two outliers were identified in the CRC group. Out of 30 CRC patients, 12 individuals had right-sided CRC (12/30; 40%). Majority of the CRC patients had stage III (13/30; 43%) or IV (13/30; 43%) cancer. Most of the CRC patients had moderately (15/30; 50%) or poorly (11/30; 37%) differentiated CRC. Samples were obtained from the peripheral venous blood and investigation of the serum IgG anti-laminarin antibodies was performed by means of ELISA and measured in U/mL. Results: Serum anti-laminarin antibodies were significantly higher in controls compared to the CRC group (16.23 ± 6.60; 11.41 ± 5.53; p = 0.015) and in controls compared to left-sided carcinoma (11.38 ± 5.39; p = 0.046). A statistically significant difference was observed between controls and CRC stage III (11.01 ± 3.36; p = 0.017) and between controls and CRC stage IV (10.98 ± 6.06; p = 0.049). Anti-laminarin antibodies were significantly lower in moderately differentiated CRC compared to controls (10.78 ± 5.22; p = 0.020), but not in poorly differentiated CRC (12.10 ± 6.28; p = 0.755). No difference was identified between controls and females with CRC (11.94 ± 6.39; p = 0.092). There was a significant difference between controls and males with CRC (10.72 ± 4.32; p = 0.017). Conclusion: Serum anti-laminarin antibodies were significantly lower in the CRC group and CRC subgroups compared to controls. Key words: colorectal cancer– anti-laminarin antibodies – tumorous bio­logy

Diagnostic accuracy of Fusobacterium nucleatum IgA and IgG ELISA test in colorectal cancer

The colorectal cancer is a serious health problem. The diagnosis of the disease mostly relies on an invasive procedure. A non-invasive diagnostic test such as an immunoassay, may facilitate diagnosis of colorectal cancer. The purpose of the study was to evaluate the use of antibodies against Fusobacterium nucleatum in the diagnosis of colorectal cancer (CRC). Totally 78 patients in three groups were included in the study. F. nucleatum in the tissues was detected using quantitative polymerase chain reaction assay. F. nucleatum IgA and IgG were measured using enzyme linked immunosorbent assay. F. nucleatum was detected in 86.7% and 73.1% cases of CRC and precancerous-benign colon disease (P-BCD), respectively. The OD values from F. nucleatum IgA and IgG ELISA tests were higher in CRC group compared with healthy individuals. The sensitivity of IgA ELISA test varied between 31.8 and 95.5% depending on the chosen cut-off values. The positivity rate of antibodies in patients with high amount of F. nucleatum in tissue was significantly greater than in the negative group. The F. nucleatum IgA and IgG antibodies in CRC were higher than the ones in healthy controls but the discriminative ability of the ELISA test was not adequate to be considered as a diagnostic tool.

Sequencing of RAS/RAF pathway genes in primary colorectal cancer and matched liver and lung metastases

BackgroundMutations in the RAS/RAF pathway predict resistance to anti-epidermal growth factor receptor antibodies in colorectal cancer (CRC), and may be targets for future therapies. This study investigates concordance of BRAF, HRAS, KRAS, NRAS and PIK3CA mutation status in primary CRC with matched liver (n = 274), lung (n = 114) or combined liver and lung metastases (n = 14).MethodsNext generation sequencing was performed on DNA from formalin-fixed paraffin embedded CRC and matched liver and/or lung metastases, for recurrent mutations in BRAF, HRAS, KRAS, NRAS and PIK3CA and using the single-molecule molecular inversion probe method.ResultsPaired sequencing results on all five genes were reached in 249 of the 402 cases (62%). The obtained number of unique reads was not always sufficient to confidently call the absence or presence of mutations for all regions of interest. The mutational status of matched pairs was highly concordant; 91.1% concordance for all five genes, 95.5% for KRAS, 99.1% for NRAS. Lung metastases more often harboured RAS mutations compared to liver metastases (71% vs. 48%, p < 0.001).ConclusionsIn this large series of CRC we show that both primary tumors and corresponding metastases can be used to determine the mutational status for targeted therapy, given the high concordance rates. Next generation sequencing including a single molecule tags is feasible, however in combination with archival formalin-fixed paraffin embedded material is limited by coverage depth.

Analysis of Anti-Glycan IgG and IgM Antibodies in Colorectal Cancer.

We propose an approach that allows simultaneous determination of the levels of M and G isotypes of antibodies to the panel of glycans using microarrays. The level of IgG antibodies to 3'-O-su-Lea glycan detects patients with colorectal cancer with a sensitivity of 69.77% and specificity of 62.75%. The percentage of correctly classified colorectal cancer patients with the use of a combination of two markers IgM antibodies to glycans 3'-sialyl-TF and 3'-O-su-Lea is as high as 74.23%. The levels of IgM antibodies to 3'-O-su-Lea glycan differ significantly in patients with and without regional metastases. The levels of some of antiglycan IgM or IgG antibodies differed significantly in patients with tumors of different location and differentiation.

Clinicopathological Significance of BRAFV600E Mutation in Colorectal Cancer: An Updated Meta-Analysis.

Background and Aims: Numerous studies have identified BRAFV600E mutation as a predictive factor of anti-EGFR antibodies in colorectal cancer (CRC). However, the association between BRAFV600E mutation and clinicopathological features remains unclear. Therefore, we aimed to conduct an updated and comprehensive meta-analysis to evaluate the above issues.Methods: We performed a systematic literature search from PubMed, Web of Science, Embase, and PMC database examining the association between BRAFV600E mutation and clinicopathological features in CRC patients. Odds ratio with 95% confidence interval were used to estimate the effects of BRAFV600E mutation on each clinicopathological parameter with fixed-effect model or random-effect model.Results: Sixty-one studies published, including 32407 CRC patients from multiple countries, were included in the meta-analysis. The overall BRAFV600E mutation rate was 11.38%, and BRAFV600E mutation was positively related to high disease stage (OR=0.81; 95% CI=0.72-0.92; P=0.001), high T stage (OR=0.51; 95% CI=0.40-0.65; P<0.00001), proximal colon (OR=4.76; 95% CI=3.81-5.96; P<0.00001) or right colon (OR=5.15; 95% CI=4.35-6.10, P<0.00001) tumor location, poor tumor differentiation (OR=0.27; 95% CI=0.21-0.34; P<0.00001), mucinous histology (OR=2.97; 95% CI=2.37-3.72; P<0.00001), K-ras-wild type (OR=0.04; 95% CI=0.02-0.07; P<0.00001), TP53-wild type (OR=0.50; 95% CI=0.31-0.78; P=0.003), deficient DNA mismatch repair (OR=2.93; 95% CI=1.78-4.82; P<0.00001), high microsatellite instability (OR=11.15; 95% CI=8.51-14.61; P<0.00001) and high CpG island methylator phenotype (OR=0.04; 95% CI=0.03-0.08; P<0.00001).Conclusions: Our updated meta-analysis demonstrated that BRAFV600E mutation was related to poor prognosis of CRC and associated with the distinct molecular phenotypes.

PO-306 Targeting CD70-positive cancer associated fibroblasts to tackle the immune suppressive tumour microenvironment in colorectal cancer

IntroductionTumour progression and invasiveness are determined not only by the malignant cancer cells themselves but also by the surrounding tumour microenvironment, comprising of cancer-associated fibroblasts (CAFs). CAFs represent a heterogeneous population with both cancer-promoting and cancer-restraining actions, lacking specific markers to target them. Expression of the immune checkpoint CD70 is normally tightly regulated and limited to cells of the lymphoid lineage. Instead, tumours hijack CD70 to facilitate immune evasion by increasing the amount of suppressive regulatory T cells (Tregs), inducing T cell apoptosis and skewing T cells towards T cell exhaustion. In this study, we aimed at exploring the expression patterns of CD70 in colorectal cancer (CRC), not merely focusing on the tumour cells, but also taking the tumour microenvironment into account.Material and methodsWe have analysed the prognostic value of CD70 expression by immunohistochemistry in CRC specimens and studied its relationship with well-known fibroblast markers, microsatellite instability and Tregs. Furthermore, primary CAF cell lines were used to study the role of CD70 on migration and immune escape.Results and discussionsWe revealed prominent expression of CD70 on a specific subset of CAFs in invasive CRC specimens. Cancer cells show almost no expression of CD70. CD70+ CAFs proved to be an independent adverse prognostic marker. Functionally, CD70+ CAFs stimulated migration and significantly increased the frequency of naturally occurring Tregs. Finally, experiments aimed at therapeutically targeting these CD70-positive CAFs are currently being analysed using 2D and 3D models.ConclusionWe have identified the expression of CD70 on CAFs as a novel prognostic marker for CRC. Performing this research, we found evidence of a cross talk between CD70+ CAFs and naturally occurring Tregs, paving the way towards immune escape. As such, this study provides a strong rationale for our ongoing exploration of CD70-targeting antibodies in CRC, especially in light of the limited immunotherapeutic options available in CRC.

Restoring PUMA induction overcomes KRAS-mediated resistance to anti-EGFR antibodies in colorectal cancer.

Intrinsic and acquired resistance to anti-EGFR antibody therapy, frequently mediated by mutant or amplified KRAS oncogene, is a significant challenge in the treatment of colorectal cancer (CRC). However, the mechanism of KRAS-mediated therapeutic resistance is not well understood. In this study, we demonstrate that clinically used anti-EGFR antibodies, including cetuximab and panitumumab, induce killing of sensitive CRC cells through p73-dependent transcriptional activation of the pro-apoptotic Bcl-2 family protein PUMA. PUMA induction and p73 activation are abrogated in CRC cells with acquired resistance to anti-EGFR antibodies due to KRAS alterations. Inhibition of aurora kinases preferentially kills mutant KRAS CRC cells and overcomes KRAS-mediated resistance to anti-EGFR antibodies in vitro and in vivo by restoring PUMA induction. Our results suggest that PUMA plays a critical role in meditating the sensitivity of CRC cells to anti-EGFR antibodies, and that restoration of PUMA-mediated apoptosis is a promising approach to improve the efficacy of EGFR-targeted therapy.

Unveiling a CD70-positive subset of cancer-associated fibroblasts marked by pro-migratory activity and thriving regulatory T cell accumulation

ABSTRACTCancer-associated fibroblasts (CAFs) are involved in the proliferative and invasive behavior of colorectal cancer (CRC). Nonetheless, CAFs represent a heterogeneous population with both cancer-promoting and cancer-restraining actions, lacking specific markers to target them. Expression of the immune checkpoint molecule CD70 is normally limited to cells of the lymphoid lineage. Instead, tumor cells hijack CD70 to facilitate immune evasion by increasing the amount of suppressive regulatory T cells (Tregs). The aim of this study was to explore CD70 expression patterns in CRC, not merely focusing on the tumor cells, but also taking the tumor stromal cells into account. We have analyzed the prognostic value of CD70 expression by immunohistochemistry in CRC specimens and its relationship with well-known fibroblast markers and Tregs. In addition, in vitro experiments were conducted to unravel the role of CD70-positive CAFs on migration and immune escape. We reveal prominent expression of CD70 on a specific subset of CAFs in invasive CRC specimens. Cancer cells show almost no expression of CD70. The presence of CD70-positive CAFs proved to be an independent adverse prognostic marker. Functionally, CD70-positive CAFs stimulated migration and significantly increased the frequency of naturally occurring Tregs. In conclusion, we have identified the expression of CD70 on CAFs as a novel prognostic marker for CRC. We have found evidence of a cross talk between CD70+ CAFs and naturally occurring Tregs, paving the way towards immune escape. As such, this study provides a strong rationale for the exploration of CD70-targeting antibodies in CRC.

Potential diagnostic value of serum p53 antibody for detecting colorectal cancer: A meta-analysis.

Numerous studies have assessed the diagnostic value of serum p53 (s-p53) antibody in patients with colorectal cancer (CRC); however, results remain controversial. The present study aimed to comprehensively and quantitatively summarize the potential diagnostic value of s-p53 antibody in CRC. The present study utilized databases, including PubMed and EmBase, systematically regarding s-p53 antibody diagnosis in CRC, accessed on and prior to 31 July 2016. The quality of all the included studies was assessed using quality assessment of studies of diagnostic accuracy (QUADAS). The result of pooled sensitivity, pooled specificity, positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were analyzed and compared with overall accuracy measures using diagnostic odds ratios (DORs) and area under the curve (AUC) analysis. Publication bias and heterogeneity were also assessed. A total of 11 trials that enrolled a combined 3,392 participants were included in the meta-analysis. Approximately 72.73% (8/11) of the included studies were of high quality (QUADAS score >7), and all were retrospective case-control studies. The pooled sensitivity was 0.19 [95% confidence interval (CI), 0.18–0.21] and pooled specificity was 0.93 (95% CI, 0.92–0.94). Results also demonstrated a PLR of 4.56 (95% CI, 3.27–6.34), NLR of 0.78 (95% CI, 0.71–0.85) and DOR of 6.70 (95% CI, 4.59–9.76). The symmetrical summary receiver operating characteristic curve was 0.73. Furthermore, no evidence of publication bias or heterogeneity was observed in the meta-analysis. Meta-analysis data indicated that s-p53 antibody possesses potential diagnostic value for CRC. However, discrimination power was somewhat limited due to the low sensitivity.

PL 04.02 Where We Are Now, and Where We Will Be in 10 years: From Asian Perspective

PL 04.02 Where We Are Now, and Where We Will Be in 10 years: From Asian Perspective

MABp1 for the treatment of colorectal cancer

ABSTRACTIntroduction: Inflammation is an established process in colorectal cancer development and a hallmark of progression, and pro-inflammatory cytokines have been implicated in the morbidity and functional compromise associated with malignancy. MABp1, described as a first-in-class true human antibody against interleukin-1α, has undergone clinical trial evaluation in a number of indications, recently completing late phase clinical trial testing under Fast Track designation for cancer anorexia-cachexia syndrome in colorectal cancer patients. To date, MABp1 has been evaluated as a novel therapeutic strategy to ameliorate phenotypic factors associated with poor prognosis in colorectal cancer patients.Areas covered: In this review, the authors discuss the clinical trial data available to date for this antibody in colorectal cancer, including novel clinical trial endpoints utilized to evaluate sarcopenia and inflammation, as well as the proposed role of interleukin-1α antagonism in leading to improved patient outcomes.Expert opinion: There is a multitude of antibodies in therapeutic development in oncology, and MABp1 is a novel class of antibody which has been safely tolerated to date. Clinical studies of this agent suggest a significant improvement in lean body mass, though additional results evaluating the impact of targeting inflammation as a strategy to delay disease progression in this population are awaited.

Abstract 642: Detection of circulating antibodies against KRAS in patients with advanced cancers

Abstract Introduction: KRAS gene plays a major role in tumorigenesis, cell proliferation and survival. Yet, there has been no effective targeted therapy against KRAS mutation-mediated tumors. We hypothesized that KRAS can induce humoral-mediated immune response. Methods: Plasma or serum samples from patients with progressing advanced cancers with or without KRAS mutations were tested for the presence of circulating KRAS antibodies. We used the Maverick Detection System (Genalyte, San Diego, CA), which can perform real-time detection of macromolecules in crude samples using biologically functionalized silicon photonic biosensors lithographically printed on disposable silicon chips. Results: We collected serum or plasma samples from 213 patients with advanced cancers (KRAS-mutant, N=100; KRAS wild-type, N=113) and 50 (23%) were found to have circulating KRAS antibodies. There was no association between KRAS antibodies and tumor KRAS mutation status (21/100, 21% for KRAS-mutant vs. 29/113, 26% for KRAS wild-type; P=0.52). In addition, there was no difference in detection of KRAS antibodies in colorectal cancer (21/89, 24%) compared to other cancers (29/124, 23%; P=1.00). There was no difference in the median survival in patients with KRAS antibodies compared to patients without KRAS antibodies (9.0 months vs. 10.1 months; P= 0.825). Similarly, there was no difference in the median survival according to the presence of circulating KRAS antibodies in subgroups of patients with tumor KRAS mutations (P= 0.96) and without tumor KRAS mutations (P=0.63). On the contrary, the median survival of patients with tumor KRAS mutation was shorter compared to patients with KRAS wild-type (7.2 months vs. 11.5 months; P&amp;lt;0.001). Conclusion: Circulating KRAS antibodies can be detected in 23% of patients with advanced cancers. Biological implications of circulating KRAS antibodies remain to be understood. Citation Format: Ed Kheder, Helen J. Huang, Alice Wu, David S. Hong, Sarina A. Piha-Paul, Daniel D. Karp, Siqing Fu, Vivek Subbiah, Apostolia M. Tsimberidou, Aung Naing, Adi Diab, Milind Javle, Scott Kopetz, Anil K. Sood, Jonathan M. Kurie, Funda Meric-Bernstam, Martin Gleeson, Filip Janku. Detection of circulating antibodies against KRAS in patients with advanced cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 642. doi:10.1158/1538-7445.AM2017-642