Prognostic value of MACC1 and proficient mismatch repair status for recurrence risk prediction in stage II colon cancer patients: the BIOGRID studies

Prognostic risk stratification value of MACC1 expression in patients with gastric cancer

BACKGROUND

The prognostic significance of metastasis-associated in colon cancer-1 (MACC1) has been explored in a variety of malignancies. However, its clinical relevance in patients with gastric cancer (GC) is limited, also remains controversial.

METHOD

In this study, we retrospectively evaluated the prognostic value of lesion MACC1 expression in 347 GC patients. Lesion MACC1 expression was analyzed with immunohistochemistry and grouped as MACC1low (n = 172) and MACC1high (n = 175) cases.

RESULTS

Data revealed that the degree of MACC1 expression is not related to patient sex, age and disease stage (all p > 0.05). Survival analysis showed that only post-operation advanced pT (p = 0.018), pN (p < 0.001), pM (p = 0.001) and AJCC stages (p < 0.001) are significantly associated with shorter survival, while no obvious difference was observed between MACC1low and MACC1high cases (p = 0.158). However, we found that survival for female (p = 0.032), older (p = 0.028), and early disease stage (pT stage I + II, p = 0.033) patients with MACC1high are remarkably worse than those with MACC1low.

CONCLUSION

In summary, our findings revealed that, though MACC1 expression is not associated with the survival of the whole cohort, the prognostic risk stratification value of lesion MACC1 expression in subgroups of patients with gastric cancer should be noted.

Identification of MACC1 as a potential biomarker for pulmonary arterial hypertension based on bioinformatics and machine learning

BACKGROUND

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by abnormal early activation of pulmonary arterial smooth muscle cells (PASMCs), yet the underlying mechanisms remain to be elucidated.

METHODS

Normal and PAH gene expression profiles were obtained from the Gene Expression Omnibus (GEO) database and analyzed using gene set enrichment analysis (GSEA) to uncover the underlying mechanisms. Weighted gene co-expression network analysis (WGCNA) and machine learning methods were deployed to further filter hub genes. A number of immune infiltration analysis methods were applied to explore the immune landscape of PAH. Enzyme-linked immunosorbent assay (ELISA) was employed to compare MACC1 levels between PAH and normal subjects. The important role of MACC1 in the progression of PAH was verified through Western blot and real-time qPCR, among others.

RESULTS

39 up-regulated and 7 down-regulated genes were identified by 'limma' and 'RRA' packages. WGCNA and machine learning further narrowed down the list to 4 hub genes, with MACC1 showing strong diagnostic capacity. In vivo and in vitro experiments revealed that MACC1 was highsly associated with malignant features of PASMCs in PAH.

CONCLUSIONS

These findings suggest that targeting MACC1 may offer a promising therapeutic strategy for treating PAH, and further clinical studies are warranted to evaluate its efficacy.

Discovery of tetrazolo-pyridazine-based small molecules as inhibitors of MACC1-driven cancer metastasis

Metastasis is directly linked to poor prognosis of cancer patients and warrants search for effective anti-metastatic drugs. MACC1 is a causal key molecule for metastasis. High MACC1 expression is prognostic for metastasis and poor survival. Here, we developed novel small molecule inhibitors targeting MACC1 expression to impede metastasis formation. We performed a human MACC1 promoter-driven luciferase reporter-based high-throughput screen (HTS; 118.500 compound library) to identify MACC1 transcriptional inhibitors. HTS revealed 1,2,3,4-tetrazolo[1,5-b]pyridazine-based compounds as efficient transcriptional inhibitors of MACC1 expression, able to decrease MACC1-induced cancer cell motility in vitro. Structure-activity relationships identified the essential inhibitory core structure. Best candidates were evaluated for metastasis inhibition in xenografted mouse models demonstrating metastasis restriction. ADMET showed high drug-likeness of these new candidates for cancer therapy. The NFκB pathway was identified as one mode of action targeted by these compounds. Taken together, 1,2,3,4-tetrazolo[1,5-b]pyridazine-based compounds are effective MACC1 inhibitors and pose promising candidates for anti-metastatic therapies particularly for patients with MACC1-overexpressing cancers, that are at high risk to develop metastases. Although further preclinical and clinical development is necessary, these compounds represent important building blocks for an individualized anti-metastatic therapy for solid cancers.

MACC1-Dependent Antitumor Effect of Curcumin in Colorectal Cancer

Metastasis is the main reason for the high mortality rate of colorectal cancer (CRC) patients. Despite the whole improvement in the field of cancer medicine, the treatment options for the patient in the late stages are very restricted. Our previous studies have elucidated metastasis-associated in colon cancer 1 (MACC1) as a direct link to metastasis formation. Therefore, we have aimed to inhibit its expression by using natural products, which are recently the center of most studies due to their low side effects and good tolerability. In this study, we have investigated the effect of one of the promising natural products, curcumin, on MACC1 expression and MACC1-induced tumor-promoting pathways. Curcumin reduced the MACC1 expression, restricted the MACC1-induced proliferation, and was able to reduce the MACC1-induced cell motility as one of the crucial steps for the distant dissemination of the tumor. We further showed the MACC1-dependent effect of curcumin on clonogenicity and wound healing. This study is, to our knowledge, the first identification of the effect of curcumin on the restriction of cancer motility, proliferation, and colony-forming ability by using MACC1 as a target.

Combinatorial treatment with statins and niclosamide prevents CRC dissemination by unhinging the MACC1-β-catenin-S100A4 axis of metastasis

Colorectal cancer (CRC) is the second-most common malignant disease worldwide, and metastasis is the main culprit of CRC-related death. Metachronous metastases remain to be an unpredictable, unpreventable, and fatal complication, and tracing the molecular chain of events that lead to metastasis would provide mechanistically linked biomarkers for the maintenance of remission in CRC patients after curative treatment. We hypothesized, that Metastasis-associated in colorectal cancer-1 (MACC1) induces a secretory phenotype to enforce metastasis in a paracrine manner, and found, that the cell-free culture medium of MACC1-expressing CRC cells induces migration. Stable isotope labeling by amino acids in cell culture mass spectrometry (SILAC-MS) of the medium revealed, that S100A4 is significantly enriched in the MACC1-specific secretome. Remarkably, both biomarkers correlate in expression data of independent cohorts as well as within CRC tumor sections. Furthermore, combined elevated transcript levels of the metastasis genes MACC1 and S100A4 in primary tumors and in blood plasma robustly identifies CRC patients at high risk for poor metastasis-free (MFS) and overall survival (OS). Mechanistically, MACC1 strengthens the interaction of β-catenin with TCF4, thus inducing S100A4 synthesis transcriptionally, resulting in elevated secretion to enforce cell motility and metastasis. In cell motility assays, S100A4 was indispensable for MACC1-induced migration, as shown via knock-out and pharmacological inhibition of S100A4. The direct transcriptional and functional relationship of MACC1 and S100A4 was probed by combined targeting with repositioned drugs. In fact, the MACC1-β-catenin-S100A4 axis by statins (MACC1) and niclosamide (S100A4) synergized in inhibiting cancer cell motility in vitro and metastasis in vivo. The MACC1-β-catenin-S100A4 signaling axis is causal for CRC metastasis. Selectively repositioned drugs synergize in restricting MACC1/S100A4-driven metastasis with cross-entity potential.

A potential role for metastasis-associated in colon cancer 1 (MACC1) as a pan-cancer prognostic and immunological biomarker

BACKGROUND

Metastasis-Associated in Colon Cancer 1(MACC1) is a validated biomarker for metastasis and is linked to survival. Although extensive experimental evidence indicates an association between MACC1 and diverse cancers, no pan-cancer analyses have yet been performed for this marker, and the role of MACC1 in immunology remains unknown.

MATERIAL AND METHODS

In our study, we performed the analysis of MACC1 expression and its influence on prognosis using multiple databases, including TIMER2, GEPIA2, Kaplan-Meier plotter. MACC1 promoter methylation levels were evaluated using the UALCAN database. Based on the TCGA database, we explored the relationship between MACC1 and tumor mutational burden (TMB), microsatellite instability (MSI), immune checkpoints using the R programming language. We evaluated the association between MACC1 and immune infiltration via TIMER and UALCAN.

RESULTS

Our results revealed that abnormal DNA methylation may be an important cause for the different expression of MACC1 across cancer types. Meanwhile, we explored the potential oncogenic roles of MACC1 and found significant prognostic value. MACC1 may be related to T-cell function and the polarization of tumor-associated macrophages, especially in STAD and LGG. Its expression was associated with immune infiltration and was found to be closely related to immune checkpoint-associated genes, especially CD274 and SIGLEC15, indicating that MACC1 may be a potential immune therapeutic target for several malignancies. Our paper reveals for the first time the relationship between MACC1 and cancer immunology.

CONCLUSIONS

MACC1 might act as a predictor for the immune response in cancer patients, and could also represent a new potential immunotherapeutic target.

Association of MACC1 expression with lymphatic metastasis in colorectal cancer: A nested case-control study

MACC1 gene is a newly discovered gene and plays an important role in the metastasis of colorectal cancer (CRC). The objective of this study was to investigate whether MACC1 is an independent factor associated with lymphatic metastasis in CRC patients. We analyzed the association between MACC1 expression and lymphatic metastasis in a nested case-control study including 99 cases and 198 matched controls in CRC patients, assessed from August 2001 to March 2015. Cases were defined as lymphatic metastasis and non-lymphatic metastasis according to AJCC TNM stages; for each case, two age-matched control without lymphatic and distant metastasis was randomly selected from the study participants. Demographic, variables about metastasis and MACC1 expression were collected. In multivariate analysis, the OR (95% CI) of MACC1 expression was 1.5 (1.1 to 2.0) in patients with lymphatic metastasis versus non-lymphatic metastasis after adjusting all variables. After adjustment for all variables and age stratification, MACC1 expression was found to be an independent risk factor for lymph node metastasis in the middle-aged group (OR 2.1, 95%CI 1.1–4.0). A nonlinear relationship between MACC1 expression and 64–75 age group was observed. The probability of metastasis slightly increased with the MACC1 level lower than turning point 1.4. At the same time, the probability of lymphatic metastasis was obviously increased even after adjusting all variables when MACC1 level higher than 1.4 (OR 11.2, 95% CI 1.5–81.5; p = 0.017) in the middle age group. The expression of MACC1 was not associated with lymphatic metastasis in populations younger than 64 or older than 75. The results demonstrates that increased MACC1 level in 64–75 age group might be associated with lymphatic metastasis in CRC patients.

The newly identified MEK1 tyrosine phosphorylation target MACC1 is druggable by approved MEK1 inhibitors to restrict colorectal cancer metastasis

Cancer metastasis causes >90% of cancer deaths and remains a major treatment challenge. Here we deciphered the impact of tyrosine phosphorylation of MACC1, a causative driver for cancer metastasis, for cancer cell signaling and novel interventions to restrict cancer metastasis. We identified MACC1 as new MEK1 substrate. MEK1 directly phosphorylates MACC1, leading to accelerated and increased ERK1 activation. Mutating in silico predicted hierarchical MACC1 tyrosine phosphorylation sites abrogates MACC1-induced migration, invasion, and MET expression, a transcriptional MACC1 target. Targeting MEK1 by RNAi or clinically applicable MEK1 inhibitors AZD6244 and GSK1120212 reduces MACC1 tyrosine phosphorylation and restricts MACC1-induced metastasis formation in mice. Although MEK1 levels, contrary to MACC1, are not of prognostic relevance for CRC patients, MEK1 expression was found indispensable for MACC1-induced metastasis. This study identifies MACC1 as new MEK1 substrate for tyrosine phosphorylation decisively impacting cell motility, tumor growth, and metastasis. Thus, MAP kinase signaling is not linear leading to ERK activation, but branches at the level of MEK1. This fundamental finding opens new therapeutic options for targeting the MEK1/MACC1 axis as novel vulnerability in patients at high risk for metastasis. This might be extended from CRC to further solid tumor entities.

Characteristics and outcomes of participants in colorectal cancer biomarker trials versus a real-world cohort

BACKGROUND

The restrictive eligibility criteria of therapy-focused cancer clinical trials can limit the external validity of the results. The characteristics and survival outcomes of patients enrolled in stand-alone biomarker studies have yet to be explored. We examined the characteristics of patients enrolled in a series of biomarker studies in stage II and III colorectal cancer (CRC) and of the broader patient population from which the study cohorts were recruited.

MATERIAL AND METHODS

We examined three distinct trial scenarios: a retrospective cohort study (RCS) where archival tissue samples were analyzed, a prospective observational study (POS) where blood samples were collected but patients received standard treatment and a randomized clinical trial (RCT) where biomarker analysis could inform clinical care. Clinical data for each study time period were extracted from a prospective registry.

RESULTS

For all CRC patients (n = 4033) in this study, the median age was 70 years and 54% were ECOG 0. For patients in the RCS (n = 450), POS (n = 284) and RCT (n = 230), the median age was 72, 65 and 64 years, with 45%, 74% and 79% being ECOG 0. For the POS and RCT, 33% and 36% of all patients with the relevant disease stage were enrolled over the study recruitment period. Survival outcomes were similar for patients in the RCS and POS. RCT outcome data are not available.

CONCLUSION

As for therapy-based trials, enrollment in prospective biomarker studies may be selective, despite relatively broad eligibility criteria. Characteristics and recruitment were similar for POS and RCT patients, indicating study complexity may not necessarily limit patient recruitment. For the prospective biomarker study cohorts examined, the selective recruitment did not significantly impact survival outcomes, suggesting potential for high external validity.

Immunohistochemistry-Based Consensus Molecular Subtypes as a Prognostic and Predictive Biomarker for Adjuvant Chemotherapy in Patients with Stage II Colorectal Cancer

Background

For stage II colorectal cancer (CRC), the efficacy of adjuvant chemotherapy remains controversial. Consensus molecular subtype (CMS) has been validated to be a prognostic tool for CRCs. In this study, CMS status was investigated as a prognostic biomarker for the efficacy of adjuvant chemotherapy for stage II colorectal cancer.

Materials and Methods

The tissue microarray was retrospectively constructed of 165 nonconsecutive, primary, and sporadic stage II CRCs. CMS status was determined by immunohistochemistry staining of CDX2, HTR2B, FRMD6, and ZEB1, combining with microsatellite instability testing. The prognostic for adjuvant chemotherapy efficacy of CMS status was calculated by Kaplan‐Meier curves and Cox regression analysis. Subgroup analyses were conducted according to tumor location.

Results

Kaplan‐Meier curves indicated that CMS was associated with overall survival (OS) and disease‐free survival for stage II CRCs. Cox regression analysis showed that CMS was an independent risk factor for OS. Among high‐risk clinicopathological factors, patients with CMS2/3 (hazard ratio [HR]: 0.445, 95% confidence interval [CI]: 0.227–0.875), left‐sided tumors (HR: 0.488, 95% CI: 0.247–0.968), or fewer than 12 lymph nodes examined (HR: 0.307, 95% CI: 0.097–0.974) had survival benefit from adjuvant chemotherapy. Subgroup analysis showed that adjuvant chemotherapy only improved OS for patients with left‐sided tumors of CMS2/3 subtype. Regardless of CMS, right‐sided tumors had no benefit from adjuvant chemotherapy.

Conclusion

CMS is a better prognostic factor for adjuvant chemotherapy for stage II CRCs. Together with tumor location, CMS classification will aid in personalized treatment for stage II CRCs.

Implications for Practice

For stage II colorectal cancer (CRC), the efficacy of adjuvant chemotherapy remains controversial, in that its minimal benefit (no more than 5% on average) is considered not worth the toxic effects of the drugs. There are still no effective prognostic and predictive biomarkers. This study showed that consensus molecular subtype (CMS) status is a predictive marker for adjuvant chemotherapy efficacy. Patients with left‐sided tumors of CMS2/3 subtype have survival benefit by receiving adjuvant chemotherapy, which will aid in personalized treatment for stage II CRCs. Moreover, this test of CMS based on immunohistochemistry is cheap, not time consuming, and easily conducted in the laboratories of most hospitals.

Currently, no clinical evidence exists for the ability of consensus molecular subtype status to predict the efficacy of adjuvant chemotherapy for stage II colorectal cancer. This article reports results of a study that adopted an immunohistochemical‐based classifier to validate the feasibility of this approach, assessing the prognostic and predictive accuracy of consensus molecular subtype status as a biomarker for adjuvant chemotherapy compared with traditional clinicopathological high‐risk factors.

Somatic POLE exonuclease domain mutations elicit enhanced intratumoral immune responses in stage II colorectal cancer

Previous studies found patients with POLE exonuclease domain mutations (EDMs) in targeted exons were related to significant better outcomes in stage II-III colorectal cancer (CRC). The detailed mutational profile of the entire POLE exonuclease domain, tumor mutation burden (TMB) and immune cell infiltration in POLE EDMs tumors, and the prognostic value of such mutations in stage II CRCs were largely unknown to us. This study was to clarify the characteristics, immune response and prognostic value of somatic POLE EDMs in stage II CRC. A total of 295 patients with stage II CRC were sequenced by next-generation sequencing with a targeted genetic panel. Simultaneous detection of the immune cells was conducted using a five-color immunohistochemical multiplex technique. The detailed molecular characteristics, tumor-infiltrating lymphocyte (TIL) and prognostic effect of POLE EDMs in stage II CRC were analyzed. For stage II CRCs, the POLE EDMs were detected in 3.1% of patients. Patients with POLE EDMs were more prone to be microsatellite instability-high (MSI-H) (33.3% vs 11.2%, p=0.043), younger at diagnosis (median 46 years vs 62 years, p<0.001) and more common at right-sided location (66.7% vs 23.1%; p=0.003). All patients with POLE EMDs were assessed as extremely high TMB, with a mean TMB of 200.8. Compared with other stage II CRCs, POLE EDMs displayed an enhanced intratumoral cytotoxic T cell response, evidenced by increased numbers of CD8+TILs and CD8A expression. Patients with stage II CRCs could be classified into three risk subsets, with significant different 5 years disease-free survival rates of 100% for POLE EDMs, 82.0% for MSI-H and 63.0% for MSS, p=0.013. In conclusion, characterized by a robust intratumoral T cell response, ultramutated POLE EDMs could be detected in a small subset of stage II CRCs with extremely high TMB. Patients with POLE EDMs had excellent outcomes in stage II CRCs, regardless of MSI status. Sequencing of all the exonuclease domain of POLE gene is recommended in clinical practice.

Saffron Crudes and Compounds Restrict MACC1-Dependent Cell Proliferation and Migration of Colorectal Cancer Cells

The high mortality rate of colorectal cancer (CRC) patients is directly associated with metastatic dissemination. However, therapeutic options specifically for metastasis are still limited. We previously identified Metastasis-Associated in Colon Cancer 1 (MACC1) as a major causal metastasis-inducing gene. Numerous studies confirmed its value as a biomarker for metastasis risk. We investigated the inhibitory impact of saffron on MACC1-induced cancer cell growth and motility. Saffron crudes restricted the proliferation and migration of MACC1-expressing CRC cells in a concentration- and MACC1-dependent manner. Saffron delays cell cycle progression at G2/M-phase and does not induce apoptosis. Rescue experiments showed that these effects are reversible. Analysis of active saffron compounds elucidated that crocin was the main compound that reproduced total saffron crudes effects. We showed the interaction of MACC1 with the cancer stem cell (CSC) marker DCLK1, which contributes to metastasis formation in different tumor entities. Saffron extracts reduced DCLK1 with crocin being responsible for this reduction. Saffron's anti-proliferative and anti-migratory effects in MACC1-expressing cells are mediated by crocin through DCLK1 down-regulation. This research is the first identification of saffron-based compounds restricting cancer cell proliferation and motility progression via the novel target MACC1.

Decoding and targeting the molecular basis of MACC1-driven metastatic spread: Lessons from big data mining and clinical-experimental approaches

Metastasis remains the key issue impacting cancer patient survival and failure or success of cancer therapies. Metastatic spread is a complex process including dissemination of single cells or collective cell migration, penetration of the blood or lymphatic vessels and seeding at a distant organ site. Hundreds of genes involved in metastasis have been identified in studies across numerous cancer types. Here, we analyzed how the metastasis-associated gene MACC1 cooperates with other genes in metastatic spread and how these coactions could be exploited by combination therapies: We performed (i) a MACC1 correlation analysis across 33 cancer types in the mRNA expression data of TCGA and (ii) a comprehensive literature search on reported MACC1 combinations and regulation mechanisms. The key genes MET, HGF and MMP7 reported together with MACC1 showed significant positive correlations with MACC1 in more than half of the cancer types included in the big data analysis. However, ten other genes also reported together with MACC1 in the literature showed significant positive correlations with MACC1 in only a minority of 5 to 15 cancer types. To uncover transcriptional regulation mechanisms that are activated simultaneously with MACC1, we isolated pan-cancer consensus lists of 1306 positively and 590 negatively MACC1-correlating genes from the TCGA data and analyzed each of these lists for sharing transcription factor binding motifs in the promotor region. In these lists, binding sites for the transcription factors TELF1, ETS2, ETV4, TEAD1, FOXO4, NFE2L1, ELK1, SP1 and NFE2L2 were significantly enriched, but none of them except SP1 was reported in combination with MACC1 in the literature. Thus, while some of the results of the big data analysis were in line with the reported experimental results, hypotheses on new genes involved in MACC1-driven metastasis formation could be generated and warrant experimental validation. Furthermore, the results of the big data analysis can help to prioritize cancer types for experimental studies and testing of combination therapies.

MACC1-the first decade of a key metastasis molecule from gene discovery to clinical translation

Deciphering the paths to metastasis and identifying key molecules driving this process is one important issue for understanding and treatment of cancer. Such a key driver molecule is Metastasis Associated in Colon Cancer 1 (MACC1). A decade long research on this evolutionarily conserved molecule with features of a transcription factor as well as an adapter protein for versatile protein-protein interactions has shown that it has manifold properties driving tumors to their metastatic stage. MACC1 transcriptionally regulates genes involved in epithelial-mesenchymal transition (EMT), including those which are able to directly induce metastasis like c-MET, impacts tumor cell migration and invasion, and induces metastasis in solid cancers. MACC1 has proven as a valuable biomarker for prognosis of metastasis formation linked to patient survival and gives promise to also act as a predictive marker for individualized therapies in a broad variety of cancers. This review discusses the many features of MACC1 in the context of the hallmarks of cancer and the potential of this molecule as biomarker and novel therapeutic target for restriction and prevention of metastasis.

Clinical relevance of circulating MACC1 and S100A4 transcripts for ovarian cancer

Metastasis‐associated in colon cancer 1 (MACC1) and S100 calcium‐binding protein A4 (S100A4) are prominent inducers of tumor progression and metastasis. For the first time, we systematically tracked circulating serum levels of MACC1 and S100A4 transcripts in the course of surgery and chemotherapy and analyzed their clinical relevance for ovarian cancer. MACC1 and S100A4 transcripts were quantified in a total of 318 serum samples from 79 ovarian cancer patients by RT‐qPCR and digital droplet PCR, respectively. MACC1 and S100A4 transcripts were significantly elevated in serum of ovarian cancer patients, compared to healthy controls (P = 0.024; P < 0.001). At primary diagnosis, high levels of MACC1 or S100A4 correlated with advanced FIGO stage (P = 0.042; P = 0.008), predicted suboptimal debulking surgery and indicated shorter progression‐free survival (PFS; P = 0.003; P = 0.001) and overall survival (OS; P = 0.001; P = 0.002). This is the first study in ovarian cancer to propose circulating MACC1 and S100A4 transcripts as potential liquid biopsy markers.

Prognostic and Risk Stratification Value of Lesion MACC1 Expression in Colorectal Cancer Patients

The up-regulated metastasis-associated in colon cancer 1 (MACC1) expression and its clinical significance has been explored in a varity of malignancies. In this study, lesion MACC1 expression in 503 CRC patients (N_colon = 332, N_rectal = 171) were analyzed with immunohistochemistry, and its correlation with clinical parameters, patient survival, and its impact on prognostic stratification were evaluated. Data revealed the survival of patient with MACC1_high is markedly worse than that of MACC1_low (mean overall survival: 80.1 vs. 90.4 months; p = 0.001) and is an independent prognostic predictor (hazard ratio = 1.533; p = 0.005). More importantly, for the first time, we demonstrated that MACC1 status exhibited a significantly prognostic power for stratified clinical parameters such as patient age and gender, particular TNM status, and distinct AJCC disease stage. In summary, our findings indicated that MACC1 is a valuable prognostic and risk stratification biomarker for colorectal cancer patients.

Significance of plasma MACC1 levels on the prognostic stratification in patients with colorectal cancer

The clinical significance of metastasis‐associated in colon cancer‐1 (MACC1) has been investigated but the relevance of peripheral MACC1 levels was rather limited. Herein, our data revealed that plasma MACC1 levels in 117 colorectal cancer patients (CRC) were dramatically higher than that in normal controls (P < 0.001), and with a strong discrimination power between the two groups (AUC = 0.960, P < 0.001). Moreover, MACC1 is an independent prognostic factor for CRC patients. When clinical parameters stratified by MACC1_low and MACC1_high, MACC1 levels exhibited further significant predictive value. Summary, plasma MACC1 levels could be a useful prognostic and diagnostic biomarker, and could improve the prognostic value of traditional prognosticators for colorectal cancer patients.

EACR-MRS conference on Seed and Soil: In Vivo Models of Metastasis

New experimental tools are urgently required to better understand the metastatic process. The importance of such tools is underscored by the fact that many anti-cancer therapies are generally ineffective against established metastases. This makes a major contribution to the fact that metastatic spread is responsible for over 90% of cancer patient deaths. It was therefore timely that the recent "Seed and Soil: In Vivo Models of Metastasis" conference held in Berlin, Germany (27-29 of November 2017) aimed to give an in-depth overview of the latest research models and tools for studying metastasis, and to showcase recent findings from world-leading metastasis researchers. This Meeting Report summarises the major themes of this ground-breaking conference.

Combination of primary tumor location and mismatch repair status guides adjuvant chemotherapy in stage II colon cancer

Background

Current opinions on the benefits of adjuvant chemotherapy for stage II colon cancer are divided and reformative election of these patients is required. We examined whether the primary tumor location based on mismatch repair status and other risk factors could better inform the current guideline.

Materials and Methods

A total of 673 consecutive patients with stage II colon cancer were included in the analysis. Differences in the common clinicopathological factors between left-sided colon cancer and right-sided colon cancer were analyzed using Fisher's exact analysis. Kaplan-Meier analysis was used to distinguish the survival difference by primary tumor location and/or MMR status.

Results

RCC had a shorter overall survival (P = 0.001) and Disease-free survival (P = 0.050) than LCC but was associated with survival benefit from adjuvant chemotherapy (P = 0.001 and P = 0.011 for OS and DFS, respectively). Mismatch repair-proficient had a shorter OS (P = 0.036) and disease free survival (P = 0.034) than mismatch-repair deficient but chemotherapy improved the OS (P = 0.007). When the primary tumor location and MMR status were combined, the PMMR/RCC was the only subgroup that could benefit from adjuvant chemotherapy (P < 0.001 and P = 0.002 for OS and DFS, respectively). Other tumors such as DMMR/RCC, DMMR/LCC, and PMMR/LCC did not benefit.

Conclusions

The observed survival benefits in PMMR/RCC patients treated with adjuvant chemotherapy will allow better selection of patients for chemotherapy who are in stage II.