Marker For Colon Cancer Research Articles

Electrochemical Determination of the KRAS Genetic Marker for Colon Cancer with Modified Graphete and Graphene Paste Electrodes

ABSTRACTThe determination of KRAS was performed using electrochemical sensing devices based on graphite and graphene pastes, modified with a phthalocyanine-boron dipyrromethene (BODIPY) and azulenes dyes. The limits of quantification for KRAS were 1.54 × 10−4 µg/mL using the sensor based on the phthalocyanine-BODIPY dye and graphite, 2.64 × 10−7 µg/mL using the sensor based on 2,6-bis((E)-2-(furan-2-yl)vinyl)-4-(4,6,8-trimethylazulen-1-yl)pyridine/TiO2Pt/reduced graphene oxide, and 3.84 × 10−3 µg/mL using the sensor based on 2,6-bis((E)-2-(thiophen-3-yl)vinyl)-4-(4,6,8-trimethylazulen-1-yl)pyridine/TiO2Pt/reduced graphene oxide. Recovery measurements demonstrated the suitable analytical performance of these sensors for the early detection of colon cancer by the analysis of whole blood samples.

Abstract A25: TEM8 specific CAR T cells induce regression of patient-derived xenograft and metastatic models of triple-negative breast cancer

Abstract Lacking marked expression of human epidermal growth factor receptor 2 (HER2), estrogen receptor (ER), and progesterone receptor (PR), triple-negative breast cancer (TNBC) is a breast cancer subtype in desperate need of targeted therapy options. Tumor endothelial marker 8 (TEM8), initially identified as a tumor endothelium marker in colon cancer, has been shown to be upregulated in TNBC. To confirm this, we stained primary TNBC tissues for TEM8; in all cases TEM8 was expressed with no expression in normal breast tissue. TEM8 is expressed by TNBC cell lines as indicated by flow cytometry and Western blot. We thus engineered chimeric antigen receptor (CAR) T cells to specifically target TEM8 in TNBC. TEM8 CAR T cells distinctly recognized TEM8, secreted immunostimulatory cytokines, and killed TEM8-positive TNBC cells in vitro. In vivo, the adoptive transfer of TEM8 CAR T cells induced regression against orthotopic patient-derived xenograft (PDX) models, including the aggressive claudin-low TNBC PDX, WHIM12. Systemic administration of TEM8 CAR T cells also induced regression against a lung metastasis TNBC model. In all models, treatment with TEM8 CAR T cells resulted in a survival advantage in mice compared to controls. Hence, TEM8 may serve as an attractive targeted immunotherapy of TNBC. Citation Format: Tiara Byrd, Kristen Fousek, Antonella Pignata, Christopher Szot, Heba Samaha, Lacey Dobrolecki, Htoo Zarni Oo, Poul Sorensen, Matthew Ellis, Michael Lewis, Meenakshi Hegde, Bradley Fletcher, Brad St. Croix, Nabil Ahmed. TEM8 specific CAR T cells induce regression of patient-derived xenograft and metastatic models of triple-negative breast cancer [abstract]. In: Proceedings of the AACR Special Conference: Advances in Breast Cancer Research; 2017 Oct 7-10; Hollywood, CA. Philadelphia (PA): AACR; Mol Cancer Res 2018;16(8_Suppl):Abstract nr A25.

Extensive screening of microRNA populations identifies hsa-miR-375 and hsa-miR-133a-3 p as selective markers for human rectal and colon cancer

Extensive screening of microRNA populations identifies hsa-miR-375 and hsa-miR-133a-3 p as selective markers for human rectal and colon cancer

Abstract 4512: Doublecortin-like kinase 1 (DCLK1) correlates with Notch pathway signaling, controls metastatic characteristics in head and neck cancer

Abstract Despite advancements in the field, the 5 year survival rate of Head and Neck Squamous Cell Carcinoma (HNSCC) still hovers at 60%. In a quest for novel therapy targets for this disease, we performed an extensive and comprehensive quantitative phosphoproteomics scan on 10 HNSCC patient derived xenografts (PDXs) in order to find dysregulated phosphoproteins. DCLK1 is hyperphosphorylated but not over expressed in most of the HNSCC derived PDXs. DCLK1 has been shown to regulate epithelial-to-mesenchymal transition (EMT) as well as serving as a cancer stem cell marker in colon and pancreas cancer. DCLK1 is also associated with bad prognosis in colon, renal and oropharyngeal cancers. We performed a comprehensive transcriptome-based computational analysis on hundreds of HNSCC patients from TCGA and GEO databases. While our results confirm the role of DCLK1 in regulating EMT and focal adhesion kinase (FAK) mediated integrin signaling, we found that high DCLK1 expression also correlates with NOTCH pathway signaling signatures in HNSCC. We have selected 5 cell HNSCC cell lines (JHU-011, JHU-022, JHU-029, FaDu and Cal29) that express DCLK1, and inhibited DCLK1 with LRRK2-in1 inhibitor and siRNA. DCLK1 inhibition resulted in substantially decreased proliferation, migration, and colony formation. Furthermore, these effects paralleled downregulation NOTCH1 signaling in all cell lines tested. Overall, our results demonstrate the novel role of DCLK1 in regulating the NOTCH signaling network and suggest its potential as a therapeutic target in HNSCC. Citation Format: Esther Channah Broner, Tejaswini Subbannayya, Jayshree Advani, Alex Zhavoronkov, Artem Artemov, Ivan Ozerov, Ido Sloma, Harsha Gowda, David Sidransky, Eugene Izumchenko, Aditi Chatterjee. Doublecortin-like kinase 1 (DCLK1) correlates with Notch pathway signaling, controls metastatic characteristics in head and neck cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4512.

Extensive screening of microRNA populations identifies hsa-miR-375 and hsa-miR-133a-3p as selective markers for human rectal and colon cancer.

MicroRNAs (miRNAs) are ∼22-nt molecules exerting control of protein expression in cancer tissues. The current study determined the full spectrum of miRNA dysregulation in freshly isolated human colon or rectal cancer biopsies as well as in controls of healthy adjacent tissue (total of n = 100) using an Illumina sequencing technology. In this work, we aimed to identify miRNAs that may serve as future marker to discern between these two subtypes. DESeq2 analysis revealed 53 significantly dysregulated miRNAs in colon cancer, 67 miRNAs in rectal cancer, and 97 miRNAs in both at a Padj value < 0.05 and ≥ 10 read counts. 65% of miRNAs were upregulated in colon as well as rectal cancer. Highest significant dysregulation (Padj < 0.00001) was detected for hsa-miR-21-5p, -215-5p and -378a in both colon and rectal cancer. Among the group of miRNAs with Padj < 0.05 and more than 2-fold expression differences, hsa-miR-375 was detected in rectal cancer only, and hsa-miR-133a-3p only in colon cancer. Receiver operating characteristic (ROC) analysis confirmed highly distinct sensitivities for hsa-miR-375 to detect rectal cancer (area under the curve (AUC): 0.9), while hsa-miR-133a-3p (AUC: 0.89) had the highest sensitivity for detecting colon cancer. We conclude that hsa-miR-375 and hsa-miR-133a-3p may serve as new markers of rectal or colon cancer and should be further investigated to search for different etiologies of colorectal cancer.

SIGNATURES OF ANTI-THOMSEN — FRIEDENREICH ANTIGEN ANTIBODY DIVERSITY IN COLON CANCER PATIENTS

To determine whether the structural and functional diversities of naturally occurring antibodies to the Thomsen- Friedenreich (TF) antigen may be of diagnostic and prognostic value in colon cancer. Serum samples were taken from patients with colon cancer (n = 94) and healthy controls (n = 64). The level of TF-specific antibody isotypes and their sialylation were determined using ELISA and lectin-ELISA with synthetic TF-polyacrylamide conjugate as an antigen and a sialic acid-specific Sambucus nigra agglutinin (SNA). The avidity was determined using ammonium thiocyanate as a chaotrope. The accuracy of diagnostics was evaluated using the receiver operator characteristic curve analysis and the survival analysis employing the Kaplan- Meier method. Compared to healthy controls, patients with colon cancer exhibited a lower level of anti-TF IgG antibodies, significantly lower ratios of TF-specific IgG/IgM and IgG/IgA, an increased SNA reactivity of anti-TF antibodies, mostly on account of IgG, and a lower avidity of TF-specific antibodies, especially their SNA-reactive subset. An increased SNA reactivity of anti-TF IgG was observed already at the early stages of cancer (p = 0.0004). The decrease of the ratio of IgG/IgM and IgG/IgA showed a good accuracy of diagnostics with about 60% sensitivity at 90% specificity. A similar potential was found for the SNA binding/IgG level index. The high level of TF-specific IgA antibodies was associated with a lower survival rate (hazard ratio = 0.34). This is the first report ever on the colon cancer-related signatures of anti-TF antibody diversity which show diagnostic potential, including in early cancer, and prognostic value. The hypersialylation of TF-specific antibodies appeared to be a common phenomenon in cancer. The signatures may be used as non-invasive antibody-based markers for colon cancer.

Surface enhanced Raman detection of the colon cancer biomarker cytidine by using magnetized nanoparticles of the type Fe3O4/Au/Ag.

Cytidine is regarded as an early marker of colon cancer. The authors describe a surface enhanced Raman scattering (SERS) technique to detect trace levels of cytidine in urine. The Raman band at 784cm-1 can be acquired best. Compared to earlier methods, an improvement in detection sensitivity by a factor of 6.2 × 105 is achieved by using a magnetically induced method in which cytidine is captured in the vicinity of the SERS hot spots of the type Fe3O4/Au/Ag. Cytidine can be quantified at 1nM levels by this method which is simple and reliable. Graphical Abstract Clusters consisting of magnetite (Fe3O4) nanoparticles, gold nanoparticles and silver nanoparticles were prepared and used in a SERS based method for detection of cytidine in urine by using magnetic improvement. The lowest detectable concentration of cytidine are at the nM level.

Microsatellite instability as a predictive marker for response to neoadjuvant chemoradiation in locally advanced rectal cancer.

806 Background: Microsatellite instability (MSI) is a marker for hypermutability due to impaired DNA mismatch repair and has been shown to be a favorable prognostic marker in colon cancer. We examined the role of MSI in locally advanced rectal cancer (LARC) as a predictive marker for response to neoadjuvant chemoradiation (CRT). Methods: We identified T3-T4 or ≥ N1 rectal cancer with reported MSI status in the National Cancer Data Base from 2007 – 2012. Patients were eligible if they were treated with CRT followed by surgical resection. Squamous cell and carcinoid histologies were excluded. The primary outcome was neoadjuvant rectal (NAR) score, categorized as low ( &lt; 8), intermediate (8-16), and high ( &gt; 16), representing a good, intermediate, and poor response to CRT, respectively. The secondary outcomes were complete pathologic response (ypCR) rate and overall survival (OS). Chi-square, Fisher’s exact, and independent sample t-tests were used to compare MSI status. Multivariable logistic regression models were used to examine factors associated with increasing level of NAR score and ypCR. OS was examined using multivariable Cox proportional hazards models. Results: A total of 1849 patients were eligible for the study and were classified as MSI-high (n = 52) or MSI-low/stable (n = 1797). Patients in the MSI-high group were younger (median age 50.5 vs 57.0, p = 0.005) and had higher rates of mucinous and signet ring histology (p &lt; 0.001), clinical T4 disease (p = 0.001), and clinically positive lymph nodes (p = 0.049). The two groups did not differ in gender, race, grade, or resection margin status. While clinical T and N stage, histology, LVI, tumor grade, and PNI were correlated with the NAR score groups, MSI-high status was not significantly associated with a higher NAR score group on multivariable analysis (OR 1.168, 95% CI 0.673 – 2.028). The MSI-high group also did not differ significantly from MSI-low/stable group in ypCR rate (OR 0.748, 95% CI 0.179 – 3.115) or OS (HR 1.727, 95% CI 0.864 – 3.453) on multivariable analysis. Conclusions: MSI status in LARC was not associated with NAR score, ypCR rate, or OS. Our results do not support the use of MSI status as a predictive marker for response to CRT in LARC.

Nuclear factor-kappa B as potential therapeutic target in human colon cancer

It has been proved that nuclear factor-kappa B (NF-κB) is activated in all cells, promotes proliferation of cells, regulates the immunological and inflammatory response, and contribute to the pathogenesis of many conditions, including cancer. Many studies pointed to constitutive activation of NF-κB in cells of certain malignant tumors. The aim of the study was to analyze the role of nuclear growth factor κB as colon cancer marker and prognostic factor. The study included 59 primary colorectal tumor patients and 15 patients in control group. The tumor samples were taken during partial colectomy and colonoscopy in control group. Tissues samples were fixed and embedded in paraffin blocks and cut. Sections were used for schedule immunohistochemical staining with the application of specific antibody for NF-κB epitope. The marker expression was compared with well-known prognostic factors in colon tumors such as tumor type, stage, and grade to establish if it might be a potential prognostic factor. The results showed statistically significant difference between control group and cancer group. The expression NF-κB did not depend on the stage and grade of colon tumors.

Carcinoembryonic antigen levels of tumor-draining venous blood as a prognostic marker in colon cancer

Purpose Carcinoembryonic antigen (CEA) is a tumor marker for colorectal cancer (CRC) related to recurrence and prognosis. We examined the ability of the CEA level measured directly from a tumor drainage vein (dCEA) to predict the prognosis of CRC more accurately than those from a peripheral vein (pCEA). Methods Fifty-two patients who received curative resection for colon adenocarcinoma were enrolled. The patients were categorized into two groups according to normal pCEA (<5.9425 ng/mL, n=24) or elevated pCEA levels (≥5.9425 ng/mL, n=28). Blood was sampled at the time of surgery simultaneously from the tumor drainage vein and from the peripheral vein. Results The clinicopathologic variables showed no significant difference between the two groups. Patients with dCEA levels <20.192 ng/mL showed better disease-free (P=0.009) and overall survival (P=0.033) curves than those with dCEA levels ≥20.192 ng/mL. Elevated dCEA levels were a significant prognostic factor for overall survival and disease-free survival in Cox proportional hazard model analysis (hazard ratio [HR]=399; 95% confidence interval [CI], 16.4–9,747; P<0.001; HR=9.39, 95% CI, 1.29–68.006; P=0.026). In subgroup analysis, we compared the data of normal range of dCEA group and elevated dCEA group with normal pCEA; the overall survival rate of patients with normal dCEA was better and the disease-free survival rate was significantly better (P=0.003). Conclusion CEA levels from a tumor drainage vein can be used as more accurate prognostic markers than levels from a peripheral vein in patients with colon cancer. Keywords: Carcinoembryonic antigen, Prognosis, Colorectal cancer

Proteomic profiling of antibody-inducing immunogens in tumor tissue identifies PSMA1, LAP3, ANXA3, and maspin as colon cancer markers.

We hypothesized that cancer tissue immunogens – antigens capable of inducing specific antibody production in patients – are promising targets for development of precision diagnostics and humoral immunotherapies. We developed an innovative immuno-proteomic strategy and identified new immunogenic markers of colon cancer.Proteins from cancers and matched normal tissues were separated by 2D gel electrophoresis and blotted with serum antibodies from the same patients. Antibody-reactive proteins were sequenced by mass spectrometry and validated by Western blotting and immunohistochemistry.170 serum antibody-reactive proteins were identified only in cancerous but not matched normal. Among these, proteasome subunit alpha type 1 (PSA1), leucine aminopeptidase 3 (LAP3), annexin A3 (ANXA3), and maspin (serpin B5) were reproducibly found in tissues from three patients. Differential expression patterns were confirmed in samples from eight patients with various stages of colon adenocarcinoma and liver metastases.These tumor-resident proteins and/or their associated serum antibodies may be promising markers for colon cancer screening and early diagnosis. Furthermore, tumor tissue-specific antibodies could potentially be exploited as immunotherapeutic targets against cancer. More generally, proteomic profiling of antibody-inducing cancer-associated immunogens represents a powerful generic method for uncovering the tumor antigen-ome, i.e., the totality of immunogenic tumor-associated proteins.

The prognostic value of cancer stem-like cell markers SOX2 and CD133 in stage III colon cancer is modified by expression of the immune-related markers FoxP3, PD-L1 and CD3

Cancer stem-like cells are highly tumourigenic cells that can repopulate entire tumours after apparent successful treatment. Recent evidence suggests they interact with other cells in the tumour microenvironment, including immune cell subsets, to enhance their survival. The aim of this study was to determine whether the expression of immune cell markers in primary colon cancer impacts the prognostic significance of cancer stem-like cell marker expression. Immunohistochemistry was used to assess the expression of putative stem cell markers (ALDH1, CD44v6, CD133, Lgr5, SOX2) and immune cell related markers (CD3, CD8, FoxP3, PD-L1) in 104 patients with stage III colon cancer. Associations of marker expression with overall and cancer-specific survival were determined using Kaplan-Meier analysis. High SOX2 expression in the central tumour area was found to be an independent factor for poor cancer-specific survival [hazard ratio (HR) 6.19; 95% confidence interval (CI) 2.24-17.14; p=0.001]. When immune-related factors were taken into account, patients categorised as SOX2low/FoxP3high had good outcome (HR 0.164; 95%CI 0.066-0.406; p<0.0001) whereas patients categorised as SOX2high/PD-L1low had poor outcome (HR 8.992; 95%CI 3.397-23.803; p<0.0001). The prognostic value of the SOX2 cancer stem-like cell marker in colon cancer is modified by expression of immune-cell related factors FoxP3 and PD-L1.

A transcriptome-based protein network that identifies new therapeutic targets in colorectal cancer

BackgroundColon cancer occurrence is increasing worldwide, making it the third most frequent cancer. Although many therapeutic options are available and quite efficient at the early stages, survival is strongly decreased when the disease has spread to other organs. The identification of molecular markers of colon cancer is likely to help understanding its course and, eventually, to uncover novel genes to be targeted by drugs. In this study, we compared gene expression in a set of 95 human colon cancer samples to that in 19 normal colon mucosae, focusing on 401 genes from 5 selected pathways (Apoptosis, Cancer, Cholesterol metabolism and lipoprotein signaling, Drug metabolism, Wnt/beta-catenin). Deregulation of mRNA levels largely matched that of proteins, leading us to build in silico protein networks, starting from mRNA levels, to identify key proteins central to network activity.ResultsAmong the analyzed genes, 10.5% (42) had no reported link with colon cancer, including the SFRP1, IGF1 and ADH1B (down), and MYC and IL8 (up), whose encoded proteins were most interacting with other proteins from the same or even distinct networks. Analyzing all pathways globally led us to uncover novel functional links between a priori unrelated or rather remotely connected pathways, such as the Drug metabolism and the Cancer pathways or, even more strikingly, between the Cholesterol metabolism and lipoprotein signaling and the Cancer pathways. In addition, we analyzed the responsiveness of some of the deregulated genes essential to network activities, to chemotherapeutic agents used alone or in presence of Lovastatin, a lipid-lowering drug. Some of these treatments could oppose the deregulations occurring in cancer samples, including those of the CHECK2, CYP51A1, HMGCS1, ITGA2, NME1 or VEGFA genes.ConclusionsOur network-based approach allowed discovering genes not previously known to play regulatory roles in colon cancer. Our results also showed that selected drug treatments might revert the cancer-specific deregulation of genes playing prominent roles within the networks operating to maintain colon homeostasis. Among those genes, some could constitute novel testable targets to eliminate colon cancer cells, either directly or, potentially, through the use of lipid-lowering drugs such as statins, in association with selected anticancer drugs.

MicroRNA-449a deficiency promotes colon carcinogenesis

MicroRNAs have broad roles in tumorigenesis and cell differentiation through regulation of target genes. Notch signaling also controls cell differentiation and tumorigenesis. However, the mechanisms through which Notch mediates microRNA expression are still unclear. In this study, we aimed to identify microRNAs regulated by Notch signaling. Our analysis found that microRNA-449a (miR-449a) was indirectly regulated by Notch signaling. Although miR-449a-deficient mice did not show any Notch-dependent defects in immune cell development, treatment of miR-449a-deficient mice with azoxymethane (AOM) or dextran sodium sulfate (DSS) increased the numbers and sizes of colon tumors. These effects were associated with an increase in intestinal epithelial cell proliferation following AOM/DSS treatment. In patients with colon cancer, miR-449a expression was inversely correlated with disease-free survival and histological scores and was positively correlated with the expression of MLH1 for which loss-of function mutations have been shown to be involved in colon cancer. Colon tissues of miR-449a-deficient mice showed reduced Mlh1 expression compared with those of wild-type mice. Thus, these data suggested that miR-449a acted as a key regulator of colon tumorigenesis by controlling the proliferation of intestinal epithelial cells. Additionally, activation of miR-449a may represent an effective therapeutic strategy and prognostic marker in colon cancer.

Prognostic significance of the genetic and the immunohistochemical expression of epithelial-mesenchymal-related markers in colon cancer

Epithelial-mesenchymal transition (EMT) is one of the main events in colorectal cancer (CRC) spread. Snail-1 is a zinc transcription factor that mediates EMT in tumor cells probably by down-regulation of E-cadherin and claudin-1. To detect the expression of epithelial markers (claudin-1 and E-cadherin) and mesenchymal markers (snail-1 and vimentin) in primary cancer colon. Also, to select stage II cancer patients of a high risk that can benefit from postoperative adjuvant chemotherapy. Reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical analysis were performed to investigate snail-1, claudin-1, E-cadherin and vimentin expressions at mRNA and protein levels in fresh tissues of cancer colon and normal colonic mucosa. The correlations between the expression of these markers and clinicopathological parameters were performed. Normal colonic mucosa revealed complete membranous expression of claudin-1, preserved E-cadherin and negative snail-1 and vimentin expressions. Compared to control, the expression of snail-1 and vimentin mRNA in cancer colon was significantly up-regulated while the expression of claudin-1 and E-cadherin mRNA was significantly down-regulated. These changes were significantly associated with stage and lymph node involvement at both mRNA and protein levels (p< 0.05). There were significant negative correlations between vimentin and each of E-cadherin and claudin-1 gene expression and between snail-1 and each of E-cadherin and claudin-1 gene expression. Moreover, these changes were independent predictors of recurrence of stage II cancer colon cases. There is a clinical significance of snail-1, claudin-1, E-cadherin and vimentin as possible markers for recognizing patients with lymph node involvement, advanced stage and high incidence of tumor recurrence in cancer colon.

Association of microsatellite instability with distinct clinical and molecular characteristics in resected colon cancer: Analysis of a platform trial of the AIO colorectal study group—Colopredict Plus.

e15086 Background: High microsatellite instability (MSI-H) is a prognostic marker in resected colon cancer (CC) identified in post-hoc analysis of multiple trials. However, validation in real-life cohorts and its association with clinical and molecular markers is lacking. Methods: In Sep 2013 we started a platform trial in 49 German cancer centers recruiting patients with UICC stage II and III CC diagnosed between 2008 to 2016. MSI was tested by immunohistochemistry (IHC) of mismatch repair proteins MLH1, MSH2, MSH6 and PMS2. In case of any loss of protein expression (IHC neg), fragment length analysis (FLA) was performed, defining MSI high tumors (MSI-H) and MS stable tumors (MSS). Besides, mutations in known prognostic factors for CC such as RAS, BRAF, PI3K and others were determined by next generation sequencing (NGS). Results: By end of 2016, 1249 patients have been recruited into the trial: median age 73yrs., stage II/III: 686/563 pts. So far, tissue was analysed in 512 pts. Of these, 182 pts. were IHC neg with 116 pts. tested MSI-H upon FLA (22.7%). Median age was 73yrs., female/male: 260/252 pts., stageII/III: 292/220 pts. Association of MS status with clinical factors is shown in Table 1. Upon NGS analysis we found 16.3% BRAF mutations, 39% KRAS mutations, 2.8% NRAS mutations and 22.6% PI3K mutations. MSI-H status was significantly associated with BRAF mutation and wildtype status of RAS. Conclusions: We found a higher percentage of MSI-H cancers in our registry compared to reported data from randomised trials, possibly related to a higher median age in this real-life cohort. MSI-H was associated with female sex, primary tumor site, and distinct molecular markers and should therefore be considered a heterogeneous subgroup of CC. Updated analysis including NGS data and survival will be presented at the meeting. Clinical trial information: AIO- KRK-0413, DKRS:00004305. [Table: see text]

Association of high microsatellite instability (MSI-H) with a high immunoscore (IS) compared to PD-L1 expression and increased survival in patients (pts) with metastatic colorectal cancer (mCRC) treated with oxaliplatin (Ox) and fluoropyrimidine (FP): A pooled analysis of the AIO KRK 0207 and RO91 trials.

3595 Background: MSI-H is an established prognostic marker in early colon cancer. Moreover, MSI-H, tumor immune cell infiltration and PD-L1 expression are also discussed as potential predictive biomarkers for immunotherapy. However, little is known about the prognostic value of these biomarkers and their association among each other in mCRC. Methods: We analyzed samples from pts. with mCRC uniformly treated with a FP and Ox within two randomized AIO trials (KRK 0207 and RO91). MS status was assessed by immunohistochemistry (IHC) of mismatch repair proteins and subsequent fragment length analysis in case of protein loss or incoherent results. PD-L1 expression was determined by IHC (1% expression threshold). Tumor lymphocytic infiltration (CD8 and CD45RO) was scored according to the immunoscore (IS) concept by Galon et al (J Transl Med 2016). Results: 41/550 cases (7.5%) displayed MSI-H. The mean IS of the total population was 0.57 (SD 0.97), the IS of MSI-H pts. was significantly higher (mean of 2.4; SD 1.4; p≤0.0001). 17 cases were PD-L1 positive (pos.) (3 %), only four of these were MSI-H. MSI-H status was significantly correlated with a higher IS, but not with PD-L1 expression (table 1). There was no difference in median overall survival (mOS) between MSI-H and MS stable (MSS) pts. (mOS MSI-H/MSS: 17.6/22.5 months (mos.), log rank: p=0.85), PD-L1 negative (neg.) and pos. pts. (mOS PD-L1 neg./pos.: 22.1/28.9 mos., log rank: p=0.49) and IS high or low pts. (mOS IS high/low: 21.1/22.1mo., log rank: p=0.25). Conclusions: In contrast to early stage colon cancer, none of these parameters was prognostic in mCRC patients. Panel-sequencing with a total of 35 genes including RAS, BRAF and POL-E on cases with PD-L1 expression, high IS or MSI-H status to further characterize these cases will be reported. Clinical trial information: AIO-R091, AIO-KRK-0207: EudraCT-Nr: 2008-007974-39. [Table: see text]

Tu2026 - StarD10 as a Novel Diagnostic Marker in Colon Cancer

Tu2026 - StarD10 as a Novel Diagnostic Marker in Colon Cancer

Decreased expression of MS4A12 inhibits differentiation and predicts early stage survival in colon cancer.

Lack of normal differentiation was considered as a common defect in cancer cells. MS4A12, a colon-specific gene, belongs to MS4A family that plays an important role in differentiation, proliferation and cell cycle regulation. The aim of the study was to investigate MS4A12 role in colon cancer cell differentiation and its prognostic value in colon cancer. We used sodium butyrate (BS) to set up differentiated model of colon cancer cell line LoVo. Cell differentiation was evaluated with ALP activity and E-cadherin. We used BS (4 mmol/L) inducing differentiation of LoVo cell and found after BS treated over 48h MS4A12 variant-1 (one of MS4A12 gene transcripts) as well as ALP and E-cadherin of LoVo cells were all increased significantly. When silence MS4A12 variant-1, the elevation of ALP and E-cadherin in BS-treated cells were all inhibited. Besides, after silence MS4A12 variant-1, the cells showed significant resistances to BS function of induction cell cycle arrest and apoptosis. Survival analysis used GEO datasets GSE39582 and GSE38832 that include 681 distinct colon cancer samples. Log-rank test and Cox's proportional hazards regression were applied to analyzing single and multiple prognostic variables, respectively. In early stage colon cancer, the patients with low MS4A12 expression had a poor survival (HR=1.72; p=0.036), while in advanced stage colon cancer MS412 had little prognostic value (HR=0.89; p=0.601). These results indicated MS4A12 might relate to colon cancer cell differentiation and supposed to be a risk classification marker for early stage colon cancer.

Serine/arginine-rich splicing factors 2 (SRSF2) and SRSF4 expression patterns in Korean with colon cancer

Purpose Splicing factors play important roles in tumorigenesis. Serine/arginine-rich splicing factors 2 (SRSF2) and SRSF4 proteins, the members of SR family proteins, are dysregulated in various cancers. However, their protein expression levels and diagnostic values are unclear in colorectal cancer. Methods We quantified the protein levels of SRSF2, SRSF4, and previously known colon cancer markers (heterogeneous nuclear ribonucleoprotein A1 [HNRNPA1] and carcinoembryonic antigen [CEA]) in tumor compared with adjacent normal-looking areas (non-tumor) of the colon in Korean patients with colon cancer using immunoblot analysis. Results The protein levels of HNRNPA1 and CEA were remarkably increased in tumor compared to non-tumor tissue and up-regulated in all of the tumor samples. However, the protein levels of SRSF2 and SRSF4 in tumor tissue were reduced in contrast with those of non-tumor tissue. Conclusion None of the SRSF proteins were significantly different between the low (≤II) and high (>II) stages. Keywords: Colon cancer, Splicing factor, Serine/arginine-rich splicing factors 2, Serine/arginine-rich splicing factors 4