Current treatment for colorectal liver metastases

Propensity-score matched outcomes of resection of stage IV primary colon cancer with and without simultaneous resection of liver metastases

There is controversy in the best management of colorectal cancer liver metastasis (CLM). This study aimed to compare short-term and survival outcomes of simultaneous resection of CLM and primary colon cancer compared to resection of only colon cancer. This retrospective matched cohort study included patients from the National Cancer Database (2015-2019) with stage IV colon adenocarcinoma and synchronous liver metastases who underwent colectomy. Patients were divided into two groups: colectomy-only (resection of primary colon cancer only) and colectomy-plus (simultaneous resection of primary colon cancer and liver metastases). The groups were matched using the propensity score method. The primary outcome was short-term mortality and readmission. Secondary outcomes were conversion, hospital stay, surgical margins, and overall survival. 4082 (37.6%) of 10,862 patients underwent simultaneous resection of primary colon cancer and liver metastases. After matching, 2038 patients were included in each group. There were no significant differences between the groups in 30-days mortality (3.1% vs 3.8%, p = 0.301), 90-days (6.6% vs 7.7%, p = 0.205) mortality, 30-days unplanned readmission (7.2% vs 5.3%, p = 0.020), or conversion to open surgery (15.5% vs. 13.8%, p = 0.298). Patients in the colectomy plus group had a higher rate of lower incidence of positive surgical margins (13.2% vs. 17.2%, p = 0.001) and longer overall survival (median: 41.5 vs 28.4 months, p < 0.001). Synchronous resection of CLM did not increase the rates of short-term mortality, readmission, conversion from minimally invasive to open surgery, or hospital stay and was associated with a lower incidence of positive surgical margins.

Exploring the mystery of colon cancer from the perspective of molecular subtypes and treatment

The molecular categorization of colon cancer patients remains elusive. Gene set enrichment analysis (GSEA), which investigates the dysregulated genes among tumor and normal samples, has revealed the pivotal role of epithelial-to-mesenchymal transition (EMT) in colon cancer pathogenesis. In this study, we employed multi-clustering method for grouping data, resulting in the identification of two clusters characterized by varying prognostic outcomes. These two subgroups not only displayed disparities in overall survival (OS) but also manifested variations in clinical variables, genetic mutation, and gene expression profiles. Using the nearest template prediction (NTP) method, we were able to replicate the molecular classification effectively within the original dataset and validated it across multiple independent datasets, underscoring its robust repeatability. Furthermore, we constructed two prognostic signatures tailored to each of these subgroups. Our molecular classification, centered on EMT, hold promise in offering fresh insights into the therapy strategies and prognosis assessment for colon cancer.

Extended Right Hepatectomy following Clearance of the Left Liver Lobe and Portal Vein Embolization for Curatively Intended Treatment of Extensive Bilobar Colorectal Liver Metastases: A Single-Center Case Series

BACKGROUND

Two-staged hepatectomy (TSH) including portal vein embolization (PVE) may offer surgical treatment for extensive bilobar colorectal liver metastases (CRLM). This study aimed to investigate the feasibility and outcomes of extended right hepatectomy (ERH) within TSH including PVE for patients with extended CRLM.

METHODS

We retrospectively collected data of patients who underwent TSH for extended CRLM between 2015 and 2021 at our institution. Clearance of the left liver lobe (clear-up, CU) associated with PVE was followed by ERH.

RESULTS

Minimally invasive (n = 12, 46%, MIH) or open hepatectomy (n = 14, 54%, OH) was performed. Postoperative major morbidity and 90-day mortality were 54% and 0%. Three-year overall survival was 95%. Baseline characteristics, postoperative and long-term outcomes were comparable between MIH and OH. However, hospital stay was significantly shorter after MIH (8 vs. 15 days, p = 0.008). Additionally, the need for intraoperative transfusions tended to be lower in the MIH group (17% vs. 50%, p = 0.110).

CONCLUSIONS

ERH following CU and PVE for extended CRLM is feasible and safe in laparoscopic and open approaches. MIH for ERH may result in shorter postoperative hospital stays. Further high-volume, multicenter studies are required to evaluate the potential superiority of MIH.

DPY30 promotes colorectal carcinoma metastasis by upregulating ZEB1 transcriptional expression

DPY30 belongs to the core subunit of components of the histone lysine methyltransferase complex, which is implicated in tumorigenesis, cell senescence, and other biological events. However, its contribution to colorectal carcinoma (CRC) progression and metastasis has yet to be elucidated. Therefore, this study aimed to investigate the biological function of DPY30 in CRC metastasis both in vitro and in vivo. Herein, our results revealed that DPY30 overexpression is significantly positively correlated with positive lymph nodes, epithelial-mesenchymal transition (EMT), and CRC metastasis. Moreover, DPY30 knockdown in HT29 and SW480 cells markedly decreased EMT progression, as well as the migratory and invasive abilities of CRC cells in vitro and lung tumor metastasis in vivo. Mechanistically, DPY30 increased histone H3K4me3 level and promoted EMT and CRC metastasis by upregulating the transcriptional expression of ZEB1. Taken together, our findings indicate that DPY30 may serve as a therapeutic target and prognostic marker for CRC.

Complete Blood Count Alterations Prior to the Diagnosis of Colorectal Cancer May Help in the Detection of Synchronous Liver Metastases

Background and Aims: Colorectal cancer (CRC) represents 10% of all cancers worldwide with the highest incidence in developed countries; its incidence is also increasing in middle- and low-income countries. Population screening programs facilitate early diagnosis of the disease. When the diagnosis is carried out in advanced stages, approximately 80% of patients with liver metastases (LM) are considered unresectable at the time of diagnosis. In our study, variations in blood counts prior to CRC diagnosis were analyzed to assess whether they could be useful in identifying smaller, more manageable metastases at earlier stages for more effective treatment. Methods: A study was carried out using complete blood counts (CBCs) from CRC patients, obtained from primary health centers and the La Ribera University Hospital within La Ribera Health Department, Valencian Community, Spain, between July 2012 and September 2020. Data from CRC patients who presented synchronous liver metastasis (CRLM) were compared with those with CRC without LM at diagnosis (CRC patients). Results: Our analysis shows that at least 15 months before CRC diagnosis, a progressive alteration was observed in CBC parameters in both groups. A higher incidence of anemia (p < 0.001) was observed among CRLM patients in the three months prior to CRC diagnosis than in CRC patients showing no LM. Conclusions: A statistically significant deterioration of CBC was observed in patients with advanced-stage CRC and synchronous or early LM (CRLM) in the three months prior to diagnosis. The primary goal of incorporating CBC variations into predictive models is to identify individuals who are at a greater risk of developing metastatic colon cancer, leading to early diagnosis. Our research improves these models by highlighting a more pronounced and rapid decline in hemoglobin levels among CRLM patients. Identification of metastases at an earlier stage when they are smaller, more manageable, and more amenable to treatment may be a valuable tool to prevent their further progression.

Circulating Tumor DNA in Colorectal Cancer Liver Metastasis: Analysis of Patients Receiving Liver Resection and Transplant

PURPOSE

Liver metastases occur in about 50% of colorectal cancer cases and drive patient outcomes. Circulating tumor DNA (ctDNA) is emerging as a diagnostic, surveillance, and tumor mutational information tool.

METHODS

Patients with colorectal cancer liver metastasis (CCLM) seen in a multidisciplinary liver tumor clinic from January to August 2022 received ctDNA testing on each visit. ctDNA was obtained using the Guardant360 platform. Tumor mutational burden (TMB) is defined as the number of identified mutations per megabase of genome analyzed.

RESULTS

Fifty-two patients had available ctDNA, with 34 (65%) tested preoperatively and 18 (35%) postoperatively; nine patients had sequential pre- and postoperative testing. The median time to test result was 12 days (IQR, 10-13.5). There were a greater number of somatic mutations identified preoperatively (n = 29 v n = 11) and a greater genomic heterogeneity (P = .0069). The mean TMB score was 12.77 in those without pathologic response to cytotoxic therapy and 6.0 in those with pathologic response (P = .10). All nine patients with sequential testing were positive preoperatively, compared with just three (33.3%) postoperatively (P = .0090). Positive postoperative ctDNA was associated with the increased likelihood of disease recurrence after resection (57%) versus negative ctDNA (0%, P = .0419).

CONCLUSION

Routine ctDNA screening in patients with CCLM is logistically feasible. Liver resection and/or transplant may be associated with clearance of detectable ctDNA and a reduction in TMB or genomic heterogeneity. Persistence of ctDNA alterations postresection appears predictive of disease recurrence. Further studies are necessary to confirm these findings, and longitudinal ctDNA testing is needed to monitor changing tumor biology.

Plasma Methylated SEPT9 as a Novel Biomarker for Predicting Liver Metastasis in Colorectal Cancer

This study aimed to explore the role of plasma methylated SEPT9 (mSEPT9) in predicting liver metastasis (LM) in colorectal cancer (CRC) patients. The clinicopathological information of 115 consecutive CRC patients were collected. The differences of clinical characteristics and several biomarkers between CRC patients with LM and those with non-liver metastasis (NM) were analyzed. Multivariate logistic regression analysis was used to identify the risk factors for predicting LM in CRC patients. Receiver operating characteristic curve (ROC) analysis was applied to investigate the sensitivity and specificity of potential biomarkers in indicating the presence of LM in CRC. Compared with the CRC without LM, the levels of plasma mSEPT9 and carcinoembryonic antigen (CEA) were significantly increased in CRC with LM. Multivariate logistic regression analysis showed that plasma mSEPT9 was an independent risk factor for predicting LM in CRC. ROC curves showed that mSEPT9 and CEA could efficiently distinguish LM from NM in CRC. The area under the curve (AUC) of mSEPT9 was 0.850, which was slightly higher than that of CEA (0.842). The optimal cut-off value of mSEPT9 was 35.09 with a sensitivity of 81.82% and a specificity of 73.33%, both similar with that of CEA (sensitivity 87.27% and specificity 75.00%). In addition, the combination of mSEPT9 and CEA had a higher specificity than CEA alone (81.70% Vs 75.00%). Our findings suggest, for the first time, that plasma mSEPT9 might serve as a potential biomarker to predict LM in CRC, which deserves further in-depth study.

Cancer-on-chip: a 3D model for the study of the tumor microenvironment

The approval of anticancer therapeutic strategies is still slowed down by the lack of models able to faithfully reproduce in vivo cancer physiology. On one hand, the conventional in vitro models fail to recapitulate the organ and tissue structures, the fluid flows, and the mechanical stimuli characterizing the human body compartments. On the other hand, in vivo animal models cannot reproduce the typical human tumor microenvironment, essential to study cancer behavior and progression. This study reviews the cancer-on-chips as one of the most promising tools to model and investigate the tumor microenvironment and metastasis. We also described how cancer-on-chip devices have been developed and implemented to study the most common primary cancers and their metastatic sites. Pros and cons of this technology are then discussed highlighting the future challenges to close the gap between the pre-clinical and clinical studies and accelerate the approval of new anticancer therapies in humans.

Differences in genome, transcriptome, miRNAome, and methylome in synchronous and metachronous liver metastasis of colorectal cancer

Despite distant metastases being the critical factor affecting patients' survival, they remain poorly understood. Our study thus aimed to molecularly characterize colorectal cancer liver metastases (CRCLMs) and explore whether molecular profiles differ between Synchronous (SmCRC) and Metachronous (MmCRC) colorectal cancer. This characterization was performed by whole exome sequencing, whole transcriptome, whole methylome, and miRNAome. The most frequent somatic mutations were in APC, SYNE1, TP53, and TTN genes. Among the differently methylated and expressed genes were those involved in cell adhesion, extracellular matrix organization and degradation, neuroactive ligand-receptor interaction. The top up-regulated microRNAs were hsa-miR-135b-3p and -5p, and the hsa-miR-200-family while the hsa-miR-548-family belonged to the top down-regulated. MmCRC patients evinced higher tumor mutational burden, a wider median of duplications and deletions, and a heterogeneous mutational signature than SmCRC. Regarding chronicity, a significant down-regulation of SMOC2 and PPP1R9A genes in SmCRC compared to MmCRC was observed. Two miRNAs were deregulated between SmCRC and MmCRC, hsa-miR-625-3p and has-miR-1269-3p. The combined data identified the IPO5 gene. Regardless of miRNA expression levels, the combined analysis resulted in 107 deregulated genes related to relaxin, estrogen, PI3K-Akt, WNT signaling pathways, and intracellular second messenger signaling. The intersection between our and validation sets confirmed the validity of our results. We have identified genes and pathways that may be considered as actionable targets in CRCLMs. Our data also provide a valuable resource for understanding molecular distinctions between SmCRC and MmCRC. They have the potential to enhance the diagnosis, prognostication, and management of CRCLMs by a molecularly targeted approach.

Metachronous colorectal liver metastasis that occurred 10 years after laparoscopic colectomy: a case report

Background

Delayed onset of colorectal liver metastasis (CRLM) > 5 years after primary colorectal surgery is rare. Herein, we report a case of delayed-onset CRLM that occurred 10 years after primary surgery, for which laparoscopic hepatectomy was performed.

Case presentation

A 68-year-old man was admitted to the hospital. His medical history revealed double colon cancer detected 10 years ago, for which laparoscopic colectomy was performed. The pathological tumor–node–metastasis stages were stages I and II. Thereafter, oral floor cancer occurred 7 years after the primary surgery and was curatively resected. The annual follow-up with positron emission tomography–computed tomography (CT) identified a tumor at segment 7/8 (S7/8) of the liver with an abnormal accumulation of fluorodeoxyglucose. Dynamic CT showed a 23-mm tumor, with ring enhancement in the early phase. Magnetic resonance imaging with gadolinium–ethoxybenzyl-diethylenetriamine penta-acetic acid demonstrated that the tumor had high intensity in T2 weighted sequences and low intensity in the hepatobiliary phase. With a preoperative diagnosis of intrahepatic cholangiocarcinoma or delayed liver metastasis, laparoscopic S7/8 partial resection was performed. The operative time was 324 min, and the intraoperative bleeding volume was 35 mL. The patient was discharged on day 15 without any postoperative complications. Upon histopathological examination, the final diagnosis was CRLM. The patient has survived for 1 year without any recurrence.

Conclusions

It is important to pay attention to the occurrence of delayed-metachronous CRLM.

Nicotinamide N-Methyltransferase as Promising Tool for Management of Gastrointestinal Neoplasms

Gastrointestinal (GI) neoplasms include esophageal, gastric, colorectal, hepatic, and pancreatic cancers. They are characterized by asymptomatic behavior, being responsible for diagnostic delay. Substantial refractoriness to chemo- and radiotherapy, exhibited by late-stage tumors, contribute to determine poor patient outcome. Therefore, it is of outmost importance to identify new molecular targets for the development of effective therapeutic strategies. In this study, we focused on the enzyme nicotinamide N-methyltransferase (NNMT), which catalyzes the N-methylation reaction of nicotinamide and whose overexpression has been reported in numerous neoplasms, including GI cancers. The aim of this review was to report data illustrating NNMT involvement in these tumors, highlighting its contribution to tumor cell phenotype. Cited works clearly demonstrate the interesting potential use of enzyme level determination for both diagnostic and prognostic purposes. NNMT was also found to positively affect cell viability, proliferation, migration, and invasiveness, contributing to sustain in vitro and in vivo tumor growth and metastatic spread. Moreover, enzyme upregulation featuring tumor cells was significantly associated with enhancement of resistance to treatment with chemotherapeutic drugs. Taken together, these results strongly suggest the possibility to target NNMT for setup of molecular-based strategies to effectively treat GI cancers.

Special issue "The advance of solid tumor research in China": Discoidin domain receptor 2 promotes colorectal cancer metastasis by regulating epithelial mesenchymal transition via activating AKT signaling

Tumor metastasis is one of the main reasons for the high mortality rate associated with colorectal cancer (CRC). However, its underlying mechanisms have not been fully understood. Here, we reported that the expression of discoidin domain receptor 2 (DDR2) was significantly upregulated in CRC tissues compared with that in normal adjacent tissues. The expression level of DDR2 was negatively associated with prognosis of CRC patients. Therefore, DDR2 may play an oncogenic role in CRC development. Furthermore, DDR2 induced epithelial mesenchymal transition in CRC cells and regulated their invasive and metastatic capacity in vitro and in vivo. Mechanistically, increased DDR2 expression level activated the AKT/GSK-3β/Slug signaling pathway. In conclusion, these findings showed that DDR2 promoted CRC metastasis and DDR2 inhibition might represent an effective therapeutic strategy for local advanced and metastatic CRC treatment. This article is protected by copyright. All rights reserved.

Predictive Efficacy of Circulating Tumor Cells in First Drainage Vein Blood from Patients with Colorectal Cancer liver Metastasis

Circulating tumor cells (CTCs) are associated with metastasis. However, the low rate of detection of CTCs in peripheral vein blood (PVB) limits their clinical application. In this study, we observed higher positive rates of CTC in first drainage vein blood (FDVB) relative to peripheral venous blood (P < 0.001). Moreover, the CTC content was related to liver metastasis, T stage and CA19-9 levels. Our collective data suggest that CTCs in FDVB have good predictive utility for risk of liver metastasis of colorectal cancer (CRC), in particular, metachronous liver metastasis.

Upregulation of the transmembrane protease serine 3 mRNA level in radioresistant colorectal cancer tissues

Aim: To investigate the clinical role of transmembrane protease serine 3 (TMPRSS3) in radioresistance and prognosis of colorectal cancer (CRC). Methods: Standardized mean difference (SMD) and summary area under the curve (AUC) of TMPRSS3 were calculated by combining all available high-throughput data globally. The prognostic significance of TMPRSS3 was determined by Kaplan-Meier and Cox regression analyses. Results: TMPRSS3 was remarkably upregulated in 198 CRC radioresistant cases compared with nonradioresistance (SMD = 0.38, AUC = 0.71). Overexpression of TMPRSS3 was observed in 1601 CRC patients compared with control subjects without CRC. TMPRSS3 was a risk factor for disease-free survival of CRC with the summarized hazard ratio 1.28. Conclusion: TMPRSS3 contributes to the radioresistance and unfavorable prognosis of CRC.

Gene-Mutation-Based Algorithm for Prediction of Treatment Response in Colorectal Cancer Patients

Purpose: Despite the high mortality of metastatic colorectal cancer (mCRC), no new biomarker tools are available for predicting treatment response. We developed gene-mutation-based algorithms as a biomarker classifier to predict treatment response with better precision than the current predictive factors. Methods: Random forest machine learning (ML) was applied to identify the candidate algorithms using the MSK Cohort (n = 471) as a training set and validated in the TCGA Cohort (n = 221). Logistic regression, progression-free survival (PFS), and univariate/multivariate Cox proportional hazard analyses were performed and the performance of the candidate algorithms was compared with the established risk parameters. Results: A novel 7-Gene Algorithm based on mutation profiles of seven KRAS-associated genes was identified. The algorithm was able to distinguish non-progressed (responder) vs. progressed (non-responder) patients with AUC of 0.97 and had predictive power for PFS with a hazard ratio (HR) of 16.9 (p < 0.001) in the MSK cohort. The predictive power of this algorithm for PFS was more pronounced in mCRC (HR = 16.9, p < 0.001, n = 388). Similarly, in the TCGA validation cohort, the algorithm had AUC of 0.98 and a significant predictive power for PFS (p < 0.001). Conclusion: The novel 7-Gene Algorithm can be further developed as a biomarker model for prediction of treatment response in mCRC patients to improve personalized therapies.

Does pulmonary metastasectomy of colorectal metastases translate to better survival? A systematic review

ABSTRACT Introduction: Surgical resection of the primary and metastatic tumour is increasingly recommended in suitable patients with metastatic colorectal cancer (CRC). While the role of metastasectomy is well studied and established in colorectal liver metastasis, evidence remains limited in pulmonary metastases. This systematic review was conducted to examine the current evidence on the role of lung metastasectomy (LUM) in CRC. Methods: Three databases were systematically searched, to identify studies that compared survival outcomes of LUM, and factors that affected decision for LUM. Results: From a total of 5,477 records, 6 studies were eventually identified. Two papers reported findings from one randomised controlled trial and 4 were retrospective reviews. There was no clear survival benefit in patients who underwent LUM compared to those who did not. When compared against patients who underwent liver metastasectomy, there was also no clear survival benefit. Patients who underwent LUM were also more likely to have a single pulmonary tumour, and metachronous disease. Conclusion: The evidence suggests a role for LUM, but is limited by inherent selection bias in retrospective reviews, and the single randomised clinical trial performed was not completed. More prospective studies are required to understand the true effect of LUM on outcomes in metastatic CRC. Keywords: Colorectal cancer, pulmonary metastasectomy, pulmonary metastases, survival

Extra chromosomal DNA in different cancers: Individual genome with important biological functions

Cancer can be caused by various factors, including the malfunction of tumor suppressor genes and the hyper-activation of proto-oncogenes. Tumor-associated extrachromosomal circular DNA (eccDNA) has been shown to adversely affect human health and accelerate malignant actions. Whole-genome sequencing (WGS) on different cancer types suggested that the amplification of ecDNA has increased the oncogene copy number in various cancers. The unique structure and function of ecDNA, its profound significance in cancer, and its help in the comprehension of current cancer genome maps, renders it as a hotspot to explore the tumor pathogenesis and evolution. Illumination of the basic mechanisms of ecDNA may provide more insights into cancer therapeutics. Despite the recent advances, different features of ecDNA require further elucidation. In the present review, we primarily discussed the characteristics, biogenesis, genesis, and origin of ecDNA and later highlighted its functions in both tumorigenesis and therapeutic resistance of different cancers.

Morbidity and mortality after liver surgery for colorectal liver metastases: a cohort study in a high-volume fast-track programme

BACKGROUND

For colorectal liver metastases, surgery is a high-risk procedure due to perioperative morbidity. The objective was to assess severity of complications after fast-track liver surgery for colorectal liver metastases and their impact on morbidity and mortality.

METHODS

All patients were treated according to the same fast-track programme. Complications were graded according to the Clavien-Dindo classification for patients undergoing surgery from 2013 to 2015. Correlation between complications and length of stay was analysed by multivariate linear regression.

RESULTS

564 patient cases were included of which three patients died within 3 months (0.53%, 95% CI: 0.17-1.64%). Complications were common with Grade ≤ 2 in 167 patients (30%) and ≥ Grade 3a in 93 (16%). Patients without complications had a mean length of stay of 4.1 days, which increased with complications: 1.4 days (95% CI: 1.3-1.5) for Grade 2, 1.7 days (1.5-2.0) for Grade 3a, 2.3 days (1.7-3.0) for Grade 3b, 2.6 days (1.6-4.2) for Grade 4a, and 2.9 days (2.8-3.1) for Grade 4b. Following were associated with increased length of stay: complication severity grade, liver insufficiency, ascites, biliary, cardiopulmonary, and infectious complications.

CONCLUSIONS

Complications after liver surgery for colorectal liver metastases, in a fast track setting, were associated with low mortality, and even severe complications only prolonged length of stay to a minor degree.

Recent Advances on Immune Targeted Therapy of Colorectal Cancer Using bi-Specific Antibodies and Therapeutic Vaccines

Colorectal cancer (CRC) is a universal heterogeneous disease that is characterized by genetic and epigenetic alterations. Immunotherapy using monoclonal antibodies (mAb) and cancer vaccines are substitute strategies for CRC treatment. When cancer immunotherapy is combined with chemotherapy, surgery, and radiotherapy, the CRC treatment would become excessively efficient. One of the compelling immunotherapy approaches to increase the efficiency of CRC therapy is the deployment of therapeutic mAbs, nanobodies, bi-specific antibodies and cancer vaccines, which improve clinical outcomes in patients. Also, among the possible therapeutic approaches for CRC patients, gene vaccines in combination with antibodies are recently introduced as a new perspective. Here, we aimed to present the current progress in CRC immunotherapy, especially using Bi-specific antibodies and dendritic cells mRNA vaccines. For this aim, all data were extracted from Google Scholar, PubMed, Scopus, and Elsevier, using keywords cancer vaccines; CRC immunotherapy and CRC mRNA vaccines. About 97 articles were selected and investigated completely based on the latest developments and novelties on bi-specific antibodies, mRNA vaccines, nanobodies, and MGD007.

Liver Immune Microenvironment and Metastasis from Colorectal Cancer-Pathogenesis and Therapeutic Perspectives

A drastic difference exists between the 5-year survival rates of colorectal cancer patients with localized cancer and distal organ metastasis. The liver is the most favorable organ for cancer metastases from the colorectum. Beyond the liver-colon anatomic relationship, emerging evidence highlights the impact of liver immune microenvironment on colorectal liver metastasis. Prior to cancer cell dissemination, hepatocytes secrete multiple factors to recruit or activate immune cells and stromal cells in the liver to form a favorable premetastatic niche. The liver-resident cells including Kupffer cells, hepatic stellate cells, and liver-sinusoidal endothelial cells are co-opted by the recruited cells, such as myeloid-derived suppressor cells and tumor-associated macrophages, to establish an immunosuppressive liver microenvironment suitable for tumor cell colonization and outgrowth. Current treatments including radical surgery, systemic therapy, and localized therapy have only achieved good clinical outcomes in a minority of colorectal cancer patients with liver metastasis, which is further hampered by high recurrence rate. Better understanding of the mechanisms governing the metastasis-prone liver immune microenvironment should open new immuno-oncology avenues for liver metastasis intervention.

The CK1δ/ε-AES axis regulates tumorigenesis and metastasis in colorectal cancer

Background: Amino-terminal enhancer of split (AES) has been identified as a tumor and metastasis suppressor in some cancers including colorectal cancer (CRC), but very little is known about the regulation of AES expression.

Methods: Bioinformatics analysis was used to investigate the expression patterns of AES, CK1δ and CK1ε. The co-immunoprecipitation, GST pull-down, Western Blot, real-time PCR and immunohistochemistry were performed to study the mechanism underlying the regulation of AES expression by CK1δ/ε. The biological function was assessed by in vitro colony formation, transwell, sphere formation, tumor organoids, in vivo tumor metastasis model and patient-derived colorectal tumor xenografts (PDTX) model.

Results: A strong inverse relationship was observed between the expression of AES and the expression of CK1δ/ε. Mechanically, AES could interact with CK1δ/ε and SKP2 using its Q domain. SKP2 mediated the ubiquitination and degradation of AES in a CK1δ/ε-dependent manner. CK1δ/ε phosphorylated AES at Ser121 and accelerated the SKP2-mediated ubiquitination and degradation of AES. In colon cancer cells, CK1δ/ε antagonized the effect of wild-type AES but not that of its mutant (S121A) on Wnt and Notch signaling, leading to an increase in the expression of Wnt target genes and Notch target genes. By downregulating the expression of AES, CK1δ/ε enhanced anchorage-independent growth, migration, invasion and sphere formation in colon cancer cells. CK1δ/ε also promoted the growth of APC^min/+ colorectal tumor organoids and liver metastasis in colon cancer mouse models through the regulation of AES degradation. Furthermore, CK1 inhibitor SR3029 treatment suppressed tumor growth via stabilizing AES in APC^min/+ colorectal tumor organoids and patient-derived colorectal tumor xenografts (PDTX).

Conclusions: Our results revealed that the CK1δ/ε-AES axis is important for CRC tumorigenesis and metastasis, and targeted inhibition of this axis may be a potential therapeutic strategy for CRC.

Circulating miRNA as Biomarkers for Colorectal Cancer Diagnosis and Liver Metastasis

Colorectal cancer (CRC) is the second leading cause of cancer deaths worldwide. Stage IV CRC patients have poor prognosis with a five-year survival rate of 14%. Liver metastasis is the main cause of mortality in CRC patients. Since current screening tests have several drawbacks, effective stable non-invasive biomarkers such as microRNA (miRNA) are needed. We aim to investigate the expression of miRNA (miR-21, miR-19a, miR-23a, miR-29a, miR-145, miR-203, miR-155, miR-210, miR-31, and miR-345) in the plasma of 62 Lebanese Stage IV CRC patients and 44 healthy subjects using RT-qPCR, as well as to evaluate their potential for diagnosis of advanced CRC and its liver metastasis using the Receiver Operating Characteristics (ROC) curve. miR-21, miR-145, miR-203, miR-155, miR-210, miR-31, and miR-345 were significantly upregulated in the plasma of surgery naïve CRC patients when compared to healthy individuals. We identified two panels of miRNA that could be used for diagnosis of Stage IV CRC (miR-21 and miR-210) with an area under the curve (AUC) of 0.731 and diagnostic accuracy of 69% and liver metastasis (miR-210 and miR-203) with an AUC = 0.833 and diagnostic accuracy of 72%. Panels of specific circulating miRNA, which require further validation, could be potential non-invasive diagnostic biomarkers for CRC and liver metastasis.

ctDNA MRD Detection and Personalized Oncogenomic Analysis in Oligometastatic Colorectal Cancer From Plasma and Urine

We hypothesized that circulating tumor DNA (ctDNA) molecular residual disease (MRD) analysis without prior mutational knowledge could be performed after neoadjuvant chemotherapy to assess oligometastatic colorectal cancer (CRC) treated surgically with curative intent. We also investigated urine as an alternative analyte for ctDNA MRD detection in this nongenitourinary setting.

PATIENTS AND METHODS

We applied AVENIO targeted next-generation sequencing to plasma, tumor, and urine samples acquired on the day of curative-intent surgery from 24 prospectively enrolled patients with oligometastatic CRC. Age-related clonal hematopoiesis was accounted for by removing variants also present in white blood cells. Plasma and urine ctDNA MRD were correlated with tumor cells detected in the surgical specimen, and adjuvant treatment strategies were proposed based on ctDNA-inferred tumor mutational burden (iTMB) and targetable alterations.

RESULTS

Seventy-one percent of patients were treated with neoadjuvant chemotherapy. Tumor-naive plasma ctDNA analysis detected MRD at a median level of 0.62% with 95% sensitivity and 100% specificity, and 94% and 77% sensitivity when only considering patients treated with neoadjuvant chemotherapy and putative driver mutations, respectively. In urine, ctDNA MRD detection specificity remained high at 100%, but sensitivity decreased to 64% with median levels being 11-fold lower than in plasma (P < .0001). Personalized ctDNA MRD oncogenomic analysis revealed 81% of patients might have been candidates for adjuvant immunotherapy based on high iTMB or targeted therapy based on actionable PIK3CA mutations.

CONCLUSION

Tumor-naive plasma ctDNA analysis can sensitively and specifically detect MRD in patients with oligometastatic CRC after neoadjuvant chemotherapy. Urine-based ctDNA MRD detection is also feasible; however, it is less sensitive than plasma because of significantly lower levels. Oligometastatic patients with detectable MRD may benefit from additional personalized treatment based on ctDNA-derived oncogenomic profiling.

Advances in Modeling the Immune Microenvironment of Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer and second leading cause of cancer-related death in the US. CRC frequently metastasizes to the liver and these patients have a particularly poor prognosis. The infiltration of immune cells into CRC tumors and liver metastases accurately predicts disease progression and patient survival. Despite the evident influence of immune cells in the CRC tumor microenvironment (TME), efforts to identify immunotherapies for CRC patients have been limited. Here, we argue that preclinical model systems that recapitulate key features of the tumor microenvironment-including tumor, stromal, and immune cells; the extracellular matrix; and the vasculature-are crucial for studies of immunity in the CRC TME and the utility of immunotherapies for CRC patients. We briefly review the discoveries, advantages, and disadvantages of current in vitro and in vivo model systems, including 2D cell culture models, 3D culture systems, murine models, and organ-on-a-chip technologies.

Androsamide, a Cyclic Tetrapeptide from a Marine Nocardiopsis sp., Suppresses Motility of Colorectal Cancer Cells

A cyclic tetrapeptide, androsamide (1), was isolated from a marine actinomycete of the genus Nocardiopsis, strain CNT-189. The planar structure of 1 was assigned by the interpretation of 1D and 2D NMR spectroscopic data. The absolute configurations of constituent amino acids of 1 were determined by application of the Marfey's and advanced Marfey's methods. Androsamide (1) strongly suppressed the motility of Caco2 cells caused by epithelial-mesenchymal transition.

Taiwan Society of Colon and Rectal Surgeons (TSCRS) Consensus for Cytoreduction Selection in Metastatic Colorectal Cancer

BACKGROUND

Taiwan has witnessed a surge in the incidence of colorectal cancer (CRC), of which 40-60% metastasize. Continuous updating of cytoreductive strategies in metastatic CRC (mCRC) has contributed to median overall survival reaching 40 months. In this changing scenario, to standardize the approaches across Taiwan, a group of experts from the Taiwan Society of Colon and Rectal Surgeons (TSCRS) convened to establish evidence- and opinion-based recommendations for defining the criteria of "resectability" in mCRC.

METHODS

Over the course of one-on-one consultations, lasting 30-40 min each, with 30 medical specialists (19 colorectal surgeons, 4 general surgeons, and 7 medical oncologists) from 16 hospitals in Taiwan followed by a 2-h meeting with 8 physician experts (3 general surgeons, 4 colorectal surgeons, and 1 thoracic surgeon), 12 key questions on cytoreduction were addressed. This was further contextualized based on published literature.

RESULTS

The final consensus includes eight recommendations regarding the criteria for metastasis resection, role of local control treatment in liver potentially resectable patients, management of synchronous liver metastases, approach for peritoneal metastasis, place for resection in multiple-organ metastasis, and general criteria for resectability.

CONCLUSIONS

mCRC patients undergoing R0 resection have the greatest survival advantage following surgery. Our role as a multidisciplinary team (MDT) should be to treat potentially resectable mCRC patients as rapidly and safely as possible, and achieve R0 resection as far as possible and for as long as possible (continuum of care). This TSCRS consensus statement aims to help build clinical capacity within the MDTs, while making better use of existing healthcare resources.

Critical steps to tumor metastasis: alterations of tumor microenvironment and extracellular matrix in the formation of pre-metastatic and metastatic niche

For decades, cancer metastasis has been a heated topic for its high mortality. Previous research has shown that pre-metastatic niche and metastatic niche are the 2 crucial steps in cancer metastasis, assisting cancerous cells' infiltration, survival, and colonization at target sites. More recent studies have unraveled details about the specific mechanisms related to the modification of pro-invasion environments. Here, we will review literatures on extracellular matrix (ECM) alterations, general cancer metastasis, organ specificity, pre-metastatic niche, metastatic niche, colony formation and impact on the course of metastasis. Respectively, the metastatic mechanisms like effect of hypoxia or inflammation on pre-metastatic niche construction, as well as the interaction between cancer cells and local milieu will be discussed. Based on the evidences of metastatic niches, we revisit and discussed the "Seed and Soil" hypothesis by Paget. This review will seek to provide insight into the mechanism of metastatic organ specificity which pre-metastatic niche and metastatic niche might suggest from an evolutionary aspect.

Distant Metastasis in Colorectal Cancer Patients-Do We Have New Predicting Clinicopathological and Molecular Biomarkers? A Comprehensive Review

Colorectal cancer (CRC) remains a serious health problem worldwide. Approximately half of patients will develop distant metastasis after CRC resection, usually with very poor prognosis afterwards. Because patient performance after distant metastasis surgery remains very heterogeneous, ranging from death within 2 years to a long-term cure, there is a clinical need for a precise risk stratification of patients to aid pre- and post-operative decisions. Furthermore, around 20% of identified CRC cases are at IV stage disease, known as a metastatic CRC (mCRC). In this review, we overview possible molecular and clinicopathological biomarkers that may provide prognostic and predictive information for patients with distant metastasis. These may comprise sidedness of the tumor, molecular profile and epigenetic characteristics of the primary tumor and arising metastatic CRC, and early markers reflecting cancer cell resistance in mCRC and biomarkers identified from transcriptome. This review discusses current stage in employment of these biomarkers in clinical practice as well as summarizes current experience in identifying predictive biomarkers in mCRC treatment.

Loss of Interleukin-17RA Expression is Associated with Tumour Progression in Colorectal Carcinoma

Interleukin-17 (IL-17) is a pro-inflammatory cytokine found in various cancers. Current evidence indicates that IL-17 plays a vital role in tumour initiation and progression in colorectal carcinoma (CRC) via binding with its receptor, IL-17RA. However, the association between clinicopathological features and presence of IL-17 and IL-17RA protein in primary CRC tissues remains unclear. This study also investigates the difference between the presence of IL-17 and IL-17RA in the paired tumour tissues versus adjacent normal tissues. The presence of IL-17RA and IL-17 protein in primary CRC tissues was determined by immunohistochemistry. Associations between clinicopathological features and IL-17RA and IL-17 immunoreactivity, were analyzed by χ2 tests. We found that both IL-17RA (p = 0.001) and IL-17 (p = 0.025) in tumour cells of primary CRC tissues was significantly lower as compared to adjacent normal tissue. Positive immunoreactivity for IL-17RA and IL-17 were detected in 51.0% and 16.8% of tumour tissues, respectively. Furthermore, negative immunoreactivity of IL-17R was significantly associated with advanced stage according to TNM classifier (p = 0.027), high grade of tumour (p = 0.019), increased depth of tumour invasion (p = 0.023) and vascular invasion (p = 0.039). Positive IL-17 immunoreactivity was associated with advanced stage (p = 0.008) and lymph node metastasis (p = 0.008). Thus, this study suggests that the loss of IL-17RA expression occurs as tumour progresses and this may predict the aggressiveness of tumour whilst expression of IL-17 promotes tumour progression and lymph node metastasis. Thus, loss of IL-17RA could be a useful prognostic biomarker for tumour progression in CRC patients.

Chemotherapy-associated liver injury in colorectal cancer

Patients with colorectal cancer (CRC) have benefited significantly from advances in multimodal treatment with significant improvements in long-term survival. More patients are currently being treated with surgical resection or ablation following neoadjuvant or adjuvant chemotherapy. However, several cytotoxic agents that are administered routinely have been linked to liver toxicities that impair liver function and regeneration. Recognition of chemotherapy-related liver toxicity emphasizes the importance of multidisciplinary planning to optimize care. This review aims to summarize current data on multimodal treatment concepts for CRC, provide an overview of liver damage caused by commonly administered chemotherapeutic agents, and evaluate currently suggested protective agents.

Neoantigen-based EpiGVAX vaccine initiates antitumor immunity in colorectal cancer

Metastatic colorectal cancer (CRC) is poorly immunogenic, with limited neoantigens that can be targeted by cancer vaccine. Previous approaches to upregulate neoantigen have had limited success. In this study, we investigated the role of a DNA methyltransferase inhibitor (DNMTi), 5-aza-2'-deoxycytidine (DAC), in inducing cancer testis antigen (CTA) expression and evaluated the antitumor efficacy of a combinatorial approach with an epigenetically regulated cancer vaccine EpiGVAX and DAC. A murine model of metastatic CRC treated with combination therapy with an irradiated whole-cell CRC vaccine (GVAX) and DAC was used to assess the antitumor efficacy. DAC significantly induced expression of CTAs in CRC, including a new CTA Tra-P1A with a known neoepitope, P1A. Epigenetically modified EpiGVAX with DAC improved survival outcomes of GVAX. Using the epigenetically regulated antigen Tra-P1A as an example, our study suggests that the improved efficacy of EpiGVAX with DAC may due in part to the enhanced antigen-specific antitumor immune responses. This study shows that epigenetic therapy with DNMTi can not only induce new CTA expression but may also sensitize tumor cells for immunotherapy. Neoantigen-based EpiGVAX combined with DAC can improve the antitumor efficacy of GVAX by inducing antigen-specific antitumor T cell responses to epigenetically regulated proteins.

MiR-377-3p suppresses colorectal cancer through negative regulation on Wnt/β-catenin signaling by targeting XIAP and ZEB2

Aberrant activation of Wnt/β-catenin signaling is a common event in the development of colorectal cancer (CRC). It is important to identify new molecules and mechanisms that can negatively regulate Wnt/β-catenin signaling. MicroRNAs are considered as promising candidates for cancer diagnosis and therapy. In our study, we found that miR-377-3p was significantly decreased in CRC samples compared to the normal mucosa tissues, especially in the patients at stage III/IV. Functional studies showed that overexpression of miR-377-3p suppressed and silence of miR-377-3p enhanced the proliferation, migration and chemoresistance of CRC cells. Molecularly, miR-377-3p inhibited Wnt/β-catenin signaling by directly targeting ZEB2 and XIAP, which were the positive regulators of Wnt/β-catenin signaling. Overexpression of ZEB2/XIAP could counteract the tumor suppressing phenotypes induced by miR-377-3p. Therefore, we uncovered the anti-cancer role and the relevant mechanisms of miR-377-3p in CRC, which might provide novel targets for designing new anti-tumor strategies.

Current state of the art imaging approaches for colorectal liver metastasis

One of the most common cancers worldwide, colorectal cancer (CRC) has been associated with significant morbidity and mortality and therefore represents an enormous burden to the health care system. Recent advances in CRC treatments have provided patients with primary and metastatic CRC a better long-term prognosis. The presence of synchronous or metachronous metastasis has been associated, however, with worse survival. The most common site of metastatic disease is the liver. A variety of treatment modalities aimed at targeting colorectal liver metastases (CRLM) has been demonstrated to improve the prognosis of these patients. Loco-regional approaches such as surgical resection and tumor ablation (operative and percutaneous) can provide patients with a chance at long-term disease control and even cure in select populations. Patient selection is important in defining the most suitable treatment option for CRLM in order to provide the best possible survival benefit while avoiding unnecessary interventions and adverse events. Medical imaging plays a crucial role in evaluating the characteristics of CRLMs and disease resectability. Size of tumors, proximity to adjacent anatomical structures, and volume of the unaffected liver are among the most important imaging parameters to determine the suitability of patients for surgical management or other appropriate treatment approaches. We herein provide a comprehensive overview of current-state-of-the-art imaging in the management of CRLM, including staging, treatment planning, response and survival assessment, and post-treatment surveillance. Computed tomography (CT) scan and magnetic resonance imaging (MRI) are two most commonly used techniques, which can be used solely or in combination with functional imaging modalities such as positron emission tomography (PET) and diffusion weighted imaging (DWI). Providing up-to-date evidence on advantages and disadvantages of imaging modalities and tumor assessment criteria, the current review offers a practice guide to assist providers in choosing the most suitable imaging approach for patients with CRLM.

20(R)-Ginsenoside Rg3 Influences Cancer Stem Cell Properties and the Epithelial-Mesenchymal Transition in Colorectal Cancer via the SNAIL Signaling Axis

Background

Cancer stem cells (CSCs) have been proposed as central drivers of cancer relapse in many cancers. In the present study, we investigated the inhibitory effect of 20(R)-Ginsenoside Rg3 (Rg3R), a major active component of ginseng saponin, on CSC-like cells and the Epithelial-Mesenchymal Transition (EMT) in colorectal cancer (CRC).

Methods

The effects of ginsenoside Rg3R on the colony-forming, migration, invasion, and wound-healing abilities of CRC cells were determined in HT29 and SW620 cell lines in vitro. Further, ginsenoside Rg3R was given intraperitoneally at 5mg/kg of mouse body weight to check its effect on the metastasis of CRC cells in vivo.

Results

Ginsenoside Rg3R significantly inhibited CSC properties, but did not affect cell proliferation. Moreover, ginsenoside Rg3R treatment significantly inhibited the motility of CRC cells based on migration, invasion, and wound-healing assays. The inhibitory effects of ginsenoside Rg3R on CRC are potentially mediated by significant down-regulation of the expression of stemness genes and EMT markers in CRC cells in a SNAIL-dependent manner. Furthermore, ginsenoside Rg3R treatment decreased both the number and size of tumor nodules in the liver, lung, and kidney tissues in a metastasis mouse model.

Conclusion

These findings highlighted the potential use of ginsenoside Rg3R in clinical applications for colorectal cancer treatment.

Endoscopic stenting in colorectal cancer

Acute malignant large bowel obstruction presents as one of the few emergencies of colorectal cancer (CRC). Management of this condition can either be by (I) upfront surgery or (II) the use of self-expanding metallic stent (SEMS) as a bridge to elective surgery. For patients with metastasis, the use of SEMS is reported to enable earlier commencement of chemotherapy. Although the use of SEMS in patients with acute malignant large bowel obstruction looks promising, it is plagued by its own set of complications and divided opinion over its long-term outcomes. Conflicting data are present, and definitive indication requires further evaluation and debate. This article will describe the typical presentation of patients with acute malignant large bowel obstruction. An introduction to the SEMS insertion procedural steps will be undertaken. Following which the article aims to review the safety profile of SEMS and the short- and long-term outcomes of SEMS in both the curative and palliative setting.

miRNAs derived from cancer-associated fibroblasts in colorectal cancer

Currently, the incidence of colorectal cancer (CRC) is increasing across the world. The cancer stroma exerts an impact on the spread, invasion and chemoresistance of CRC. The tumor microenvironment involves a complex interaction between cancer cells and stromal cells, for example, cancer-associated fibroblasts (CAFs). CAFs can promote neoplastic angiogenesis and tumor development in CRC. Mounting evidence suggests that many miRNAs are overexpressed (miR-21, miR-329, miR-181a, miR-199a, miR-382 and miR-215) in CRC CAFs, and these miRNAs can influence the spread, invasiveness and chemoresistance in neighboring tumor cells via paracrine signaling. Herein, we summarize the pathogenic roles of miRNAs and CAFs in CRC. Moreover, for first time, we highlight the miRNAs derived from CRC-associated CAFs and their roles in CRC pathogenesis.

Establishment of a new non-invasive imaging prediction model for liver metastasis in colon cancer

The aim of this study was to develop and validate a new non-invasive artificial intelligence (AI) model based on preoperative computed tomography (CT) data to predict the presence of liver metastasis (LM) in colon cancer (CC). A total of forty-eight eligible CC patients were enrolled, including twenty-four patients with LM and twenty-four patients without LM. Six clinical factors and one hundred and fifty-two tumor image features extracted from CT data were utilized to develop three models: clinical, radiomics, and hybrid (a combination of clinical and radiomics features) using support vector machines with 5-fold cross-validation. The performance of each model was evaluated in terms of accuracy, specificity, sensitivity, and area under the curve (AUC). For the radiomics model, a total of four image features utilized to construct the model resulting in an accuracy of 83.87% for training and 79.50% for validation. The clinical model that employed two selected clinical variables had an accuracy of 69.82% and 69.50% for training and validation, respectively. The hybrid model that combined relevant image features and clinical variables improved accuracy of both training (90.63%) and validation (85.50%) sets. In terms of AUC, hybrid (0.96; 0.87) and radiomics models (0.91; 0.85) demonstrated a significant improvement compared with the clinical model (0.71; 0.69), and the hybrid model had the best prediction performance. In conclusion, the AI model developed using preoperative conventional CT data can accurately predict LM in CC patients without additional procedures. Furthermore, combining image features with clinical characteristics greatly improved the model's prediction performance. We have thus generated a promising tool that allows guidance and individualized surveillance of CC patients with high risks of LM.

Preparation and characterization of inorganic radioactive holmium-166 microspheres for internal radionuclide therapy

Microspheres with high specific activities of radionuclides are very interesting for internal radiotherapy treatments. This work focuses on the formulation and characterization of inorganic microspheres with a high content of holmium and therefore a high specific radioactivity of holmium-166. Two novel formulations of inorganic microspheres were obtained by dispersing solid holmium acetylacetonate microspheres (Ho₂(AcAc)₃-ms) in NaH₂PO₄ or NaOH solutions followed by 2 h incubation at room temperature. By exchange of acetylacetonate with phosphate or hydroxyl ions, holmium phosphate microspheres (HoPO₄-ms) and holmium hydroxide microspheres (Ho(OH)₃-ms) were formed respectively. The inorganic microspheres had a significantly smaller diameter (28.5 ± 4.4 μm (HoPO₄-ms) and 25.1 ± 3.5 μm (Ho(OH)₃-ms)) than those of Ho₂(AcAc)₃-ms (32.6 ± 5.2 μm). The weight percentage of holmium-165 in the microspheres increased significantly from 47% (Ho₂(AcAc)₃-ms) to 55% (HoPO₄-ms) and 73% (Ho(OH)₃-ms). After preparation of both HoPO₄-ms and Ho(OH)₃-ms, the stable holmium-165 isotope was partly converted by neutron activation into radioactive holmium-166 to yield radioactive microspheres. High specific activities were achieved ranging from 21.7 to 59.9 MBq/mg (¹⁶⁶HoPO₄-ms) and from 28.8 to 79.9 MBq/mg (¹⁶⁶Ho(OH)₃-ms) depending on the neutron activation time. The structure of both microspheres was preserved up to neutron activations of 6 h in a thermal neutron flux of 4.72 × 10¹⁶ n m^-2 s^-1. After activation, both microspheres revealed excellent stability in administration fluids (saline and phosphate buffer) having less than 0.05% of holmium released after 72 h incubation. Finally, the hemocompatibility of these inorganic microspheres was evaluated and it was shown that the microspheres did cause neither hemolysis nor depletion or inhibition of the coagulation factors of the intrinsic blood coagulation pathway meaning that the microspheres have a good hemocompatibility. Overall, this work shows that radioactive inorganic microspheres with high specific activities of holmium-166 can be prepared which potentially can be used for internal radionuclide therapy.

Intra-arterial EmboCept S® and DC Bead® effectively inhibit tumor growth of colorectal rat liver metastases

BACKGROUND

Intra-arterial therapy with embolics is established for the treatment of malignancies of the liver. However, there are no studies comparing the different effects of various embolics used in clinical practice. Herein, we analyzed the effect of 3 different embolics on tumor growth in a rat model of colorectal liver metastases.

METHODS

Eight days after subcapsular implantation of 5 × 105 colorectal cancer cells (CC531) in the left liver lobe of WAG/Rij rats were randomized into 4 groups (n = 8) and underwent intra-arterial hepatic therapy. Animals received either EmboCept S®, DC Bead® or Lipiodol® Ultra-Fluid. Animals of the control group received a comparable amount of saline. Tumor growth was measured on day 8 and 11 using a three-dimensional 40 MHz ultrasound device. On day 11 tumor and liver tissue were removed for histological and immunohistochemical analyses.

RESULTS

On day 11 animals of the control group showed a tumor growth of ~ 60% compared to day 8. Application of Lipiodol Ultra-Fluid® did not significantly influence tumor growth (~ 40%). In contrast, treatment with EmboCept S® or DC Bead® completely inhibited tumor growth. Of interest, application of EmboCept S® did not only completely inhibit tumor growth but even decreased tumor size. Immunohistochemical analysis showed a significant increase of necrotic areas within the tumors after application of EmboCept S® and DC Bead® compared to Lipiodol® Ultra-Fluid.

CONCLUSION

The present study demonstrates that an intra-arterial therapy with EmboCept S® and DC Bead®, but not Lipiodol® Ultra-Fluid, results in a complete inhibition of rat colorectal liver metastatic growth.

Prevalence, prognosis and predictive status of HER2 amplification in anti-EGFR-resistant metastatic colorectal cancer

Numerous inherent and acquired genetic alterations have been demonstrated with resistance to anti-epidermal growth factor receptor (anti-EGFR) therapy in metastatic colorectal cancer (mCRC) patients. Although the common oncogenic driver mutations identified include KRAS, NRAS, BRAF, and PI3K, recent studies report a vital role played by human epithelial growth factor receptor-2 (HER2) amplification in acquired resistance to anti-EGFR therapy. HER2 amplification has been associated with poor prognosis in many malignancies including breast and gastric cancer and is also a negative predictor of anti-EGFR therapy. Given the relevance of HER2 amplification in conferring an anti-EGFR resistance, this paper reviews the prevalence of HER2 amplification in mCRC while exploring the prognostic and predictive values of this biomarker. Further, we also discuss the results of the studies that explored the utilization of anti-HER2-targeted therapies in mCRC. HER2-directed therapies have the ability to change the treatment algorithm in clinically relevant small subset of patients with HER2-amplified mCRC.

PTPRB promotes metastasis of colorectal carcinoma via inducing epithelial-mesenchymal transition

Dysregulation of protein tyrosine phosphatase, receptor type B (PTPRB) correlates with the development of a variety of tumors. Here we show that PTPRB promotes metastasis of colorectal cancer (CRC) cells via inducing epithelial-mesenchymal transition (EMT). We find that PTPRB is expressed at significantly higher levels in CRC tissues compared to adjacent nontumor tissues and in CRC cell lines with high invasion. PTPRB knockdown decreased the number of invasive CRC cells in an in vitro wound healing model, and also reduced tumor metastasis in vivo. Conversely, PTPRB overexpression promoted CRC cell invasion in vitro and metastasis in vivo. PTPRB overexpression decreased vimentin expression and promoted E-cadherin expression, consistent with promotion of EMT, while PTPRB knockdown had the opposite effect. Hypoxic conditions induced EMT and promoted invasion in CRC cells, but these effects were eliminated by PTPRB knockdown. EMT blockade via TWIST1 knockdown inhibited the migration and invasiveness of CRC cells, and even increased PTPRB expression could not reverse this effect. Altogether, these data support the conclusion that PTPRB promotes invasion and metastasis of CRC cells via inducing EMT, and that PTPRB would be a novel therapeutic target for the treatment of CRC.

First report on extended distance between tumor lesion and adjacent organs at risk using interventionally applied balloon catheters: a simple procedure to optimize clinical target volume covering effective isodose in interstitial high-dose-rate brachytherapy of liver malignomas

Purpose

Organs at risk (OARs), which are very close to a clinical target volume (CTV), can compromise effective tumor irradiation. The present study investigated the feasibility and safety of a novel approach, in particular, the extent of the dosimetric effect of distancing CTV from adjacent OARs by means of interventionally applied balloon catheters.

Material and methods

Patients with peripheral hepatic malignancies, in whom the critical proximity of an OAR to the CTV in the assessment by contrast-enhanced magnetic resonance imaging (MRI) scans and the preplanning process were included. Additionally, patients underwent placement of an interventional balloon catheter during computed tomography (CT)-guided application of interstitial brachytherapy (iBT) catheters inserted into the tissue between hepatic capsule and adjacent OAR. The virtual position of an OAR without balloon catheter was anticipated and contoured in addition to contouring of CTV and OAR. The calculated dose values for CTV as well as 1 cc of the relevant OAR (D_1cc) with and without balloon were recorded. The D_1cc of the realized irradiation plan was statistically compared to the D_1cc of the virtually contoured OARs.

Results

In 31 cases, at least one balloon catheter was administered. The mean D_1cc of the OAR in the group with balloon(s) was 12.6 Gy compared with 16 Gy in the virtual cohort without the device, therefore significantly lower (p < 0.001). Overall, there were no acute complications. Severe (> 2 CTCAEv4.03) late complications observed in 3/31 (9.6%) patients during follow-up period after brachytherapy were most certainly not due to the balloon application. Side effects were probably associated with pre-existing serious diseases and potentially additional local late effects of the irradiation in general rather than with the balloon catheters.

Conclusions

The distancing of the adjacent OARs allows a higher D₁₀₀ value of CTV, therefore allowing for more efficient local control.

A Concise Review of Pelvic Radiation Therapy (RT) for Rectal Cancer with Synchronous Liver Metastases

Background and Objective

Colorectal cancer is a major health concern as a very common cancer and a leading cause of cancer-related mortality worldwide. The liver is a very common site of metastatic spread for colorectal cancers, and, while nearly half of the patients develop metastases during the course of their disease, synchronous liver metastases are detected in 15% to 25% of cases. There is no standardized treatment in this setting and no consensus exists on optimal sequencing of multimodality management for rectal cancer with synchronous liver metastases.

Methods

Herein, we review the use of pelvic radiation therapy (RT) as part of potentially curative or palliative management of rectal cancer with synchronous liver metastases.

Results

There is accumulating evidence on the utility of pelvic RT for facilitating subsequent surgery, improving local tumor control, and achieving palliation of symptoms in patients with stage IV rectal cancer. Introduction of superior imaging capabilities and contemporary RT approaches such as Intensity Modulated Radiation Therapy (IMRT) and Image Guided Radiation Therapy (IGRT) offer improved precision and toxicity profile of radiation delivery in the modern era.

Conclusion

Even in the setting of stage IV rectal cancer with synchronous liver metastases, there may be potential for extended survival and cure by aggressive management of primary tumor and metastases in selected patients. Despite lack of consensus on sequencing of treatment modalities, pelvic RT may serve as a critical component of multidisciplinary management. Resectability of primary rectal tumor and liver metastases, patient preferences, comorbidities, symptomatology, and logistical issues should be thoroughly considered in decision making for optimal management of patients.

Oxaliplatin-Based Intra-arterial Chemotherapy in Colo-Rectal Cancer Liver Metastases: A Review from Pharmacology to Clinical Application

Liver metastases (LM) are often consequences of colo-rectal cancer (CRC)and the majority of patients have unresectable LM. Oxaliplatin-based intravenous chemotherapy represents the gold standard treatment for CRC. Intravenous oxaliplatin has several side effects i.e., nephrologic, hematologic and neurological toxicity. Moreover, hepatic arterial infusion (HAI) of antitumor drugs deeply modifies the treatment of LMCRC due to the knowledge that LM are perfused by the hepatic artery network, whereas healthy tissue is perfused by the portal vein. Therefore, oxaliplatin-based HAI becomes an interesting possibility to treat LMCRC. The aim of this review is to shed light on the important impact of the oxaliplatin-based chemotherapy from a non-conventional clinical point of view, considering that, being universally accepted its antitumor effect if administered intravenously, fragmentary information are known about its clinical applications and benefits deriving from intra-arterial administration in loco-regional chemotherapy.

Angiopoietin-like protein 1 inhibits epithelial to mesenchymal transition in colorectal cancer cells via suppress Slug expression

The role of ANGPTL1 in cancer development is still little known, especially in colorectal cancer (CRC). We investigated the clinical significance of ANGPTL1 expression in CRC tissues and its potential role in the progression of epithelial to mesenchymal transition (EMT) in CRC cells, which has not been reported to our knowledge. ANGPTL1 expression in CRC tissues was much lower that than in paired adjacent normal tissues by IHC, WB and qRT-PCR assays. ANGPTL1 positive expression was negatively associated with tumor size (P = 0.034), T stage (P = 0.015), lymph nodes metastasis (P = 0.045) and TNM stage (P = 0.009) and poor prognosis of CRC patients (P = 0.003). In vitro, ANGPTL1 showed decreasing expression in CRC cell lines from primary tumor to ascites metastasis. Meanwhile, ANGPTL1 silencing enhanced EMT in HCT116 cells followed with the increase of Slug, Fibronectin and Vimentin, the decrease of E-cad, and the enhancement of EMT-like cell morphology and cell invasion and migration. Low ANGPTL1 expression is closely associated with multiple clinical significance and prognosis of CRC patients. ANGPTL1 inhibits EMT of CRC cells via inhibiting E-cad suppressor Slug expression.

Ginsenoside Rd Inhibits the Metastasis of Colorectal Cancer via Epidermal Growth Factor Receptor Signaling Axis

Ginsenoside Rd is a saponin from ginseng and has been reported to have various biological activities. However, the effect of ginsenoside Rd on the metastasis of colorectal cancer (CRC) remains unknown. Here, we found that ginsenoside Rd decreased the colony-forming ability, migration, invasion, and wound-healing abilities of CRC cells, although it did not affect cell proliferation. In addition, using an inverse-docking assay, we found that ginsenoside Rd bound to epidermal growth factor receptor (EGFR) with a high binding affinity, inducing the downregulation of stemness- and epithelial-mesenchymal transition-related genes; these were partially rescued by either exogenous EGF treatment or ectopic expression of SOX2. Furthermore, ginsenoside Rd significantly decreased the number and size of tumor metastasis nodules in the livers, lungs, and kidneys of mouse model of metastasis. © 2018 IUBMB Life, 71(5):601-610, 2019.