Recent advances in treatment for colorectal liver metastasis

TGF-β Modulated Pathways in Colorectal Cancer: New Potential Therapeutic Opportunities

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide, with 20% of patients presenting with metastatic disease at diagnosis. TGF-β signaling plays a crucial role in various cellular processes, including growth, differentiation, apoptosis, epithelial-mesenchymal transition (EMT), regulation of the extracellular matrix, angiogenesis, and immune responses. TGF-β signals through SMAD proteins, which are intracellular molecules that transmit TGF-β signals from the cell membrane to the nucleus. Alterations in the TGF-β pathway and mutations in SMAD proteins are common in metastatic CRC (mCRC), making them critical factors in CRC tumorigenesis. This review first analyzes normal TGF-β signaling and then investigates its role in CRC pathogenesis, highlighting the mechanisms through which TGF-β influences metastasis development. TGF-β promotes neoangiogenesis via VEGF overexpression, pericyte differentiation, and other mechanisms. Additionally, TGF-β affects various elements of the tumor microenvironment, including T cells, fibroblasts, and macrophages, promoting immunosuppression and metastasis. Given its strategic role in multiple processes, we explored different strategies to target TGF-β in mCRC patients, aiming to identify new therapeutic options.

Enhanced Therapeutic Efficacy of the Nanoscale Fluoropyrimidine Polymer CF10 in a Rat Colorectal Cancer Liver Metastasis Model

Combination chemotherapy regimens that include fluoropyrimidine (FP) drugs, e.g., 5-fluorouracil (5-FU), are central to the treatment of colorectal cancer liver metastases (CRLMs), a major cause of cancer mortality. We tested a second-generation FP polymer, CF10, in a CC531/WAGRij syngeneic orthotopic rat model of liver metastasis to determine if CF10 improved response relative to 5-FU. CF10 displayed increased potency relative to 5-FU in CC531 rat colorectal cancer cells based on clonogenic assay results and caused increased apoptosis, as shown using a live/dead assay. The increased potency of CF10 to CC531 cells was associated with increased replication stress, as assessed by Western blot for biomarkers of ATR/Chk1 and ATM/Chk2 pathway activation. CF10 dosed to deliver equivalent FP content as an established dose of 5-FU in rats (50 mg/kg) did not cause weight loss in WAGRij rats even when combined with ethynyl uracil (EU), an inhibitor of dihydropyrimidine dehydrogenase, the enzyme primarily responsible for 5-FU degradation in the liver. In contrast, 5-FU caused significant weight loss that was exacerbated in combination with EU. Importantly, CF10 was significantly more effective than 5-FU at inhibiting tumor progression (~90% reduction) in the CC531/WAG/Rij CRLM model. Our results reveal strong potential for CF10 to be used for CRLM treatment.

Relationship between hepatic surgical margins of colorectal cancer liver metastases and prognosis: A review

Colorectal cancer (CRC) remains a significant global health concern, as characterized by its high mortality rate ranking second among all the leading causes of death. The liver serves as the primary site of CRC metastasis, and the occurrence of liver metastasis is a significant contributor to mortality among patients diagnosed with CRC. The survival rate of patients with colorectal liver metastasis has significantly increased with the advancement of comprehensive tumor therapy. However, radical surgery remains the key factor. Since there are frequently multiple liver metastases, which are prone to recurrence after surgery, it is crucial to preserve as much liver parenchyma as possible without affecting the prognosis. The issue of surgical margins plays a crucial role in this regard. In this review, we begin by examining the occurrence of positive surgical margins in liver metastases of patients diagnosed with CRC. We aim to define positive margins in hepatic surgery, examine the relationship between margins and prognosis and establish a foundation for future research in this field.

Prognostic Factors Influencing Survival in Stage II and Stage III Colorectal Cancer Patients

Background Colorectal cancer (CRC) is a global health concern with rising incidence. This study analyzed demographic and clinicopathological factors influencing overall survival (OS) and disease-free survival (DFS) in Jordanian CRC patients. Methodology This retrospective, single-center study collected data from CRC patients at the Royal Medical Services, Jordan, from January 2018 to June 2020. Patient variables included disease stage, stage risk, tumor location, history of chemotherapy, and metastasis status. OS and DFS were defined as the time from surgery to death, last follow-up, or metastasis confirmation. Kaplan-Meier curves and Cox models were used for survival analysis. Results Of 127 CRC patients, 33.3% died during the follow-up period. Most patients were males (55.1%), diagnosed with stage III (55.9%), and classified as high risk (59.2%). Metastasis occurred in 24.4%, and 65.4% received chemotherapy. OS at one, two, and end of the follow-up years was 85.2%, 75.6%, and 66.9%, respectively. Metastasis-free rates were 85%, 78.5%, and 71%, respectively. Multivariate analysis showed that stage III (hazard ratio (HR) = 2.968) and high-risk stage (HR = 2.966) were associated with shorter OS and increased metastasis risk. Right-sided tumors (HR = 2.183) had shorter OS, while chemotherapy recipients (HR = 0.430) had longer OS. Stage III and high-risk stages were strong predictors of mortality, while only stage III and high-risk stages were robust predictors of metastasis. Demographic variables (sex and age) showed no significant associations with survival outcomes. Conclusions Our findings highlight the prognostic significance of disease stage, stage risk, tumor location, and chemotherapy in CRC survival among Jordanian patients. Understanding these factors can guide tailored treatment and improve outcomes.

PI3K/AKT signaling pathway as a critical regulator of epithelial-mesenchymal transition in colorectal tumor cells

Colorectal cancer (CRC) is one of the most frequent gastrointestinal malignancies that are considered as a global health challenge. Despite many progresses in therapeutic methods, there is still a high rate of mortality rate among CRC patients that is associated with poor prognosis and distant metastasis. Therefore, investigating the molecular mechanisms involved in CRC metastasis can improve the prognosis. Epithelial-mesenchymal transition (EMT) process is considered as one of the main molecular mechanisms involved in CRC metastasis, which can be regulated by various signaling pathways. PI3K/AKT signaling pathway has a key role in CRC cell proliferation and migration. In the present review, we discussed the role of PI3K/AKT pathway CRC metastasis through the regulation of the EMT process. It has been shown that PI3K/AKT pathway can induce the EMT process by down regulation of epithelial markers, while up regulation of mesenchymal markers and EMT-specific transcription factors that promote CRC metastasis. This review can be an effective step toward introducing the PI3K/AKT/EMT axis to predict prognosis as well as a therapeutic target among CRC patients. Video Abstract.

Dynamics of the prognostic nutritional index in preoperative chemotherapy in patients with colorectal liver metastases

BACKGROUND

Identifying the prognostic indicators that reflect the efficacy of preoperative chemotherapy is necessary. In this study, we investigated the prognostic indicators targeting the systemic inflammatory response for the administration of preoperative chemotherapy in patients with colorectal liver metastases.

METHODS

Data for 192 patients were retrospectively analyzed. The relationship between overall survival and clinicopathological variables, including biomarkers such as the prognostic nutritional index, was investigated in patients who underwent upfront surgery or preoperative chemotherapy.

RESULTS

In the upfront surgery group, extrahepatic lesion (p=0.01) and low prognostic nutritional index (p < 0.01) were significant prognostic indicators, whereas a decrease in the prognostic nutritional index (p=0.01) during preoperative chemotherapy were independent poor prognostic factors in the preoperative chemotherapy group. In particular, a decrease in the prognostic nutritional index was a significant prognostic marker in patients aged <75 years (p=0.04). In patients with a low prognostic nutritional index aged <75 years, preoperative chemotherapy significantly prolonged overall survival (p=0.02).

CONCLUSION

A decrease in the prognostic nutritional index during preoperative chemotherapy predicted overall survival of patients with colorectal liver metastases after hepatic resection, and preoperative chemotherapy may be effective for patients aged <75 years with a low prognostic nutritional index.

Colon-cancer liver metastasis is effectively targeted by recombinant methioninase (rMETase) in an orthotopic mouse model

BACKGROUND

Colorectal cancer liver metastasis (CCLM) is the most frequent cause of death of colorectal cancer. Development of novel new effective therapy is needed for CCLM patients to improve outcome. The aim of the present study was to investigate the efficacy of recombinant methioninase (rMETase) on a CCLM orthotopic mouse model of liver metastasis established using the human colon cancer cell line HT29 expressing red fluorescent protein (RFP).

MATERIALS AND METHODS

Orthotopic CCLM nude mouse models were randomized into two groups: control group (n = 6, PBS 200 µl, i.p., daily); rMETase group (n = 6, 100 units/200 µl, i.p., daily). Tumor volume was measured on day 0 and day 15. Body weight was measured twice a week. All mice were sacrificed on day 15.

RESULTS

rMETase significantly inhibited the increase of the liver metastasis as determined by RFP fluorescence area and intensity (p = 0.016 and 0.015, respectively). There was no significant difference of body weight between either group on any day.

CONCLUSIONS

The present study suggests that rMETase has future potential therapy for CCLM in the clinic.

Delivery of Engineered Primary Tumor-Derived Exosomes Effectively Suppressed the Colorectal Cancer Chemoresistance and Liver Metastasis

Liver metastasis is one of the major causes of colorectal cancer (CRC)-related morbidity and mortality. Delivering small interfering RNAs (siRNAs) or noncoding RNAs has been reported as a promising method to target liver metastasis and chemoresistance in CRC. Here, we report a noncoding RNA delivery system using exosomes derived from primary patient cells. Coiled-coil domain-containing protein 80 (CCDC80) was strongly associated with CRC liver metastasis and chemoresistance, a finding validated by bioinformatic analysis and clinical specimens. Silencing CCDC80 significantly increased sensitivity to chemotherapy agents in OXA-resistant cell lines and a mouse model. The primary cell-derived exosome delivery system was designed to simultaneously deliver siRNAs targeting CCDC80 and increase chemotherapy sensitivity in the distant CRC liver metastasis mouse models and patient-derived xenograft mouse models. We further validated the antitumor effect in an ex vivo model of chemoresistant CRC organoids and a patient-derived organoid xenograft model. Tumor-bearing mice treated with the siRNA-delivering exosomes and hepatectomy showed ideal overall survival. Our results provide a therapeutic target and represent a possible therapeutic alternative for patients with CRC and distant metastasis and in cases of chemoresistance.

The dilemma of the disappearing colorectal liver metastases: defining international trends in management

OBJECTIVE

This survey sought to appraise the degree of consistency in the management of disappeared colorectal liver metastases (dCRLM) among liver surgeons in different countries.

BACKGROUND

Colorectal liver metastases (CRLM) account for half of the deaths secondary to colorectal cancer. Due to the high utilization of chemotherapy before surgery, some or all CRLM can disappear (dCRLM) but management of dCRLMs remains unclear.

METHODS

Seven simulated scenarios of dCRLM were presented to experienced liver surgeons using an online platform. Treatment decisions were submitted and analysed using the multi-rater kappa method. The effect of the experience, complexity of scenarios, and location and number of dCRLM on treatment decision were analysed.

RESULTS

Sixty-seven liver surgeons from 25 countries completed the survey. There was no agreement about the therapeutic strategies of dCRLM in all scenarios (kappa 0.12, IQR 0.20-0.32). In scenarios with lower difficulty scores, surgeons tended to offer surgical resection for dCRLM alongside the visible CRLM (vCRLM), however, with poor agreement (kappa 0.32, IQR 0.19-0.51). No agreement was seen for clinical scenario in which all CRLM lesions disappeared (kappa 0.20).

CONCLUSION

There are clear inconsistencies in the management decisions of dCRLM. Better evidence is required to define optimal management strategies.

Colorectal cancer with testicular metastasis: A case report and literature review

RATIONALE

Colorectal cancer is the second leading cause of cancer-related deaths in the world. About 50% of patients will have metastases during the course of the disease. The common sites of metastasis are the liver, lung, peritoneum, lymph, etc. Metastatic carcinoma to the testes is uncommon. We found a case of ascending colon cancer metastasized to the testis in the clinic.

PATIENT CONCERNS

We reported a 50-year-old male patient who was found to have testicular metastases >4 years after intestinal cancer surgery, and multiple metastases in the peritoneum and pelvis were found 1 week later.

DIAGNOSES

After enhanced computed tomography and pathological biopsy, the patient was diagnosed with testicular metastasis of colon cancer.

INTERVENTIONS

Capecitabine combined with bevacizumab is currently undergoing palliative treatment.

OUTCOMES

The patients died of tumor progression on June 28, 2021.

LESSONS

The testicular metastasis of colorectal cancer is a sign of peritoneum and multiple metastases. When the testicular metastasis occurs in colorectal cancer patients, it usually indicates that the patient has a poor prognosis.

Impact of C-reactive protein-albumin-lymphocyte (CALLY) index on prognosis after hepatectomy for colorectal liver metastasis

AIM

The C-reactive protein (CRP)-albumin-lymphocyte (CALLY) index is a novel inflammation-based biomarker. We aimed to investigate whether the CALLY can predict the prognosis in patients with colorectal liver metastases (CRLM) after hepatic resection.

METHODS

We included 183 patients with CRLM who underwent hepatectomy. The CALLY index was defined as (albumin × lymphocytes)/(CRP × 10⁴). We investigated the association of the CALLY index with overall survival by univariate and multivariate analyses.

RESULTS

In total, 101 (55%) patients had a low CALLY index (<4). In the univariate analysis, overall survival was significantly worse in patients with lymph node metastases (p = 0.02), extrahepatic lesions (p < 0.01), and a low CALLY index (p < 0.01). In the multivariate analysis, independent and significant predictors of overall survival were lymph node metastases (p = 0.04), extrahepatic lesions (p = 0.03), and a low CALLY index (p = 0.03). Patients with a low CALLY index had significantly more postoperative complications than those with a high CALLY index (29% vs. 11%, p < 0.01).

CONCLUSION

The CALLY index may be an independent and significant indicator of outcomes in patients who underwent liver resection for CRLM.

Mechanisms of colorectal liver metastasis development

Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide, largely due to the development of colorectal liver metastases (CRLM). For the establishment of CRLM, CRC cells must remodel their tumor-microenvironment (TME), avoid the immune system, invade the underlying stroma, survive the hostile environment of the circulation, extravasate into the liver, reprogram the hepatic microenvironment into a permissive pre-metastatic niche, and finally, awake from a dormant state to grow out into clinically detectable CRLM. These steps form part of the invasion-metastasis cascade that relies on reciprocal interactions between the tumor and its ever-changing microenvironment. Such interplay provides a strong rational for therapeutically targeting the TME. In fact, several TME constituents, such as VEGF, TGF-β coreceptor endoglin, and CXCR4, are already targeted in clinical trials. It is, however, of utmost importance to fully understand the complex interactions in the invasion-metastasis cascade to identify novel potential therapeutic targets and prevent the establishment of CRLM, which may ultimately greatly improve patient outcome.

TGF-β Signaling in Metastatic Colorectal Cancer (mCRC): From Underlying Mechanism to Potential Applications in Clinical Development

Colorectal cancer (CRC) is a serious public health issue, and it has the leading incidence and mortality among malignant tumors worldwide. CRC patients with metastasis in the liver, lung or other distant sites always have poor prognosis. Thus, there is an urgent need to discover the underlying mechanisms of metastatic colorectal cancer (mCRC) and to develop optimal therapy for mCRC. Transforming growth factor-β (TGF-β) signaling plays a significant role in various physiologic and pathologic processes, and aberrant TGF-β signal transduction contributes to mCRC progression. In this review, we summarize the alterations of the TGF-β signaling pathway in mCRC patients, the functional mechanisms of TGF-β signaling, its promotion of epithelial-mesenchymal transition, its facilitation of angiogenesis, its suppression of anti-tumor activity of immune cells in the microenvironment and its contribution to stemness of CRC cells. We also discuss the possible applications of TGF-β signaling in mCRC diagnosis, prognosis and targeted therapies in clinical trials. Hopefully, these research advances in TGF-β signaling in mCRC will improve the development of new strategies that can be combined with molecular targeted therapy, immunotherapy and traditional therapies to achieve better efficacy and benefit mCRC patients in the near future.

Clinical outcomes of neoadjuvant chemotherapy for resectable colorectal liver metastasis with intermediate risk of postoperative recurrence: A multi‐institutional retrospective study

Aims

Risk-scoring systems for colorectal liver metastasis (CRLM) after hepatectomy allow prognoses to be predicted preoperatively. We investigated the clinical outcomes of neoadjuvant chemotherapy for resectable CRLM according to patient risk status, aiming to determine the subgroup of patients who could benefit from neoadjuvant chemotherapy.

Methods

In this multi-institutional retrospective analysis, the preoperative risk score was calculated from six previously reported factors: synchronous metastases, primary lymph node positivity, tumor number, largest tumor diameter, extrahepatic metastasis, and the preoperative carbohydrate antigen 19-9 level. Patients were divided into three groups according to their risk scores: low risk (score = 0), intermediate risk (score 1-10), and high risk (score ≥11). Overall and recurrence-free survival curves were calculated using the Kaplan-Meier method. After propensity-score matching in the intermediate-risk group, we compared clinicopathological features and outcomes.

Results

There were 318 cases, from 20 institutions. The preoperative risk score could be calculated in 277 cases. There were 34, 192, and 51 patients in the low-, intermediate-, and high-risk groups, respectively. Intermediate-risk group patients who received neoadjuvant chemotherapy had significantly better recurrence-free survival than that of patients without neoadjuvant chemotherapy (P = .0453). After propensity-score matching in the intermediate-risk group, the recurrence-free survival rate was better in patients who received neoadjuvant chemotherapy (P = .0261). But the overall survival rate was not improved after the matching.

Conclusion

Neoadjuvant chemotherapy for resectable CRLM might prolong the recurrence-free survival period for intermediate-risk patients with preoperative risk scores in the range of 1-10, but the overall survival was not improved by neoadjuvant chemotherapy.

Oncogenic fusion transcript analysis identified ADAP1-NOC4L, potentially associated with metastatic colorectal cancer

PURPOSE

Fusion transcripts are transcriptome-mediated alterations involved in tumorigenesis and are considered as diagnostic, prognostic, and therapeutic biomarkers. In metastatic colorectal carcinoma (mCRC), fusion transcripts are rarely reported. The main challenge is to identify driver chimeras with a significant role in cancer progression.

METHODS

In the present study, 86 RNA sequencing data samples were analyzed to discover driver fusion transcripts. Functional assays included clonogenic cell survival, wound-healing, and transwell cell invasion. Quantitative expression analysis of epithelial-mesenchymal transition (EMT), apoptotic regulators, and metastatic markers were examined for the candidate fusion genes. Kaplan-Meier survival analysis was performed using patient overall survival (OS).

RESULTS

A variety of driver fusions were identified. Fourteen fusion genes (51% of mCRC), each at least found in two mCRC samples, were determined as oncogenic fusion transcripts by in silico analysis of their functions. Among them, two recurrent chimeric transcripts confirmed by Sanger sequencing were selected. Positive expression of ADAP1-NOC4L was significantly associated with an increased risk of poor OS in mCRC patients. In vitro transforming potential for the chimera, resulting from the fusion of ADAP1 and NOC4L was assessed. Overexpression of this fusion gene increased cell proliferation and enhanced migration and invasion of CRC cells. In addition, it significantly upregulated EMT and anti-apoptotic markers.

CONCLUSIONS

ADAP1-NOC4L transcript chimera, a driver chimera identified in this study, provides new insight into the underlying mechanisms involved in the development and spread of mCRC. It suggests the potential of RNA-based alterations as novel targets for personalized medicine in clinical practice.

Extracellular Matrix Protein 1 Regulates Colorectal Cancer Cell Proliferative, Migratory, Invasive and Epithelial-Mesenchymal Transition Activities Through the PI3K/AKT/GSK3β/Snail Signaling Axis

In prior reports, extracellular matrix protein 1 (ECM1) upregulation has been reported in colorectal cancer (CRC) patient tumor tissues, and has been suggested to be related to the metastatic progression of CRC, although the underlying mechanisms have yet to be clarified. In this study, we found that ECM1 was overexpressed in both CRC tissues and cell lines. Upregulation of ECM1 was correlated with tumor size, lymph node status and TNM stage in CRC patients. Knocking down ECM1 suppressed CRC cell growth, migration and invasion, in addition to reducing the expression of Vimentin and increasing E-cadherin expression. The overexpression of ECM1, in contrast, yielded the opposite phenotypic outcomes while also promoting the expression of p-AKT, p-GSK3β, and Snail, which were downregulated when ECM1 was knocked down. Treatment with LY294002 and 740 Y-P reversed the impact upregulation and downregulation of ECM1 on CRC cell metastasis and associated EMT induction. In vivo analyses confirmed that ECM1 overexpression was able to enhance EMT induction and CRC tumor progression. In conclusion, ECM1 influences CRC development and progression in an oncogenic manner, and regulates CRC metastasis and EMT processes via the PI3K/AKT/GSK3β/Snail signaling axis.

Long disease-free interval diminishes the prognostic value of primary tumor stage for patients with colorectal cancer liver metastases

BACKGROUND

It is assumed that the impact of primary tumor stage (PTS) on prognosis gradually weakens with increasing disease-free interval (DFI) from colorectal cancer resection to liver metastases.

METHODS

Data from 733 patients undergoing hepatectomy in the Hepato-pancreato-biliary Surgery Department I of Peking University Cancer Hospital were retrospectively analyzed. Early and late metastases were defined as DFI ≤ and >12 months, respectively.

RESULTS

In early metastases group, patients with T₄ stage had a significantly worse recurrence-free survival (RFS) and overall survival (OS) than those with T_1-3 stage (P = 0.002 and P < 0.001, respectively). Patients with N_1-2 stage disease also demonstrated a worse RFS and OS than those with N₀ stage (P = 0.006 and P = 0.007, respectively). In late metastases group, patients with T₄ and T_1-3 stages as well as patients with N_1-2 and N₀ stages, had comparable RFS (P = 0.395 and P = 0.996, respectively) and OS (P = 0.387 and P = 0.684, respectively). T and N stages were independent prognostic predictors only in patients with early metastases.

CONCLUSION

The impact of PTS on prognosis is diminished with increasing DFI and limited only to patients with early metastases.

Indications for conversion hepatectomy for initially unresectable colorectal cancer with liver metastasis

PURPOSE

Selected patients with initially unresectable colorectal cancer (CRC) and liver metastases undergo conversion surgery after appropriate chemotherapy. The prognosis of these patients is good, with some even cured of the disease. This retrospective, single-institution study analyzes the clinical importance of patient characteristics on the outcomes of conversion hepatectomy.

METHODS

We evaluated 229 consecutive patients with initially unresectable CRC and liver metastasis, who underwent systemic chemotherapy. The patients were assigned to groups depending on conversion hepatectomy.

RESULTS

Conversion hepatectomy was performed in 30 patients (13.1%). The proportion of patients with extrahepatic metastasis was significantly lower in the conversion group than in the unresectable group (30.0 vs. 66.8%; P < 0.01). The rate of left-sided primary colorectal tumors was significantly higher in the conversion group than in the unresectable group (96.7 vs. 65.8%; P < 0.01). Multivariate analyses identified that left-sided tumors, no extrahepatic metastasis, H1 or H2 grade CLM, and treatment with molecular-targeted agents were associated with conversion hepatectomy (odds ratios: 16.314, 4.216, 7.631, and 4.070; P < 0.01). Overall survival was significantly longer in the conversion group than in the unresectable group (MST: 50.0 versus 14.7 months; P < 0.01).

CONCLUSION

Left-sided primary tumors, absence of extrahepatic metastases, H1 or H2 grade, and use of molecular-targeted agents were associated with successful conversion hepatectomy; thus, patients with these characteristics may be candidates for conversion therapy.

LINC01315 accelerates the growth and epithelial-mesenchymal transition of colorectal cancer cells via activating the Wnt/β-catenin signal

The pathological roles of long non-coding RNAs (lncRNAs) in colorectal carcinoma (CRC) have been corroborated. To date, the pathological contributions of LINC01315 in the epithelial-mesenchymal transition (EMT) property of CRC are still ambiguous. By silencing LINC01315, we disclosed that LINC01315 promoted the growth, metastatic characteristics, and the EMT of CRC cells in vitro. Mechanistically, LINC01315 activated Wnt/β-catenin signaling. LINC01315 bound to the β-catenin promoter and activated its transcription. In rescue experiments, ectopic overexpression of β-catenin counteracted the inhibiting effector-triggered by LINC01315 deletion. In summary, this preliminary study brings new insights to the pathological significance of the LINC01315/Wnt/β-catenin signaling pathway in CRC.

Proteome biology of primary colorectal carcinoma and corresponding liver metastases

Colorectal adenocarcinomas (CRC) are one of the most commonly diagnosed tumors worldwide. Colorectal adenocarcinomas primarily metastasize into the liver and (less often) into the peritoneum. Patients suffering from CRC-liver metastasis (CRC-LM) typically present with a dismal overall survival compared to non-metastasized CRC patients. The metastasis process and metastasis-promoting factors in patients with CRC are under intensive debate. However, CRC studies investigating the proteome biology are lacking. Formalin-fixed paraffin-embedded (FFPE) tissue specimens provide a valuable resource for comprehensive proteomic studies of a broad variety of clinical malignancies. The presented pilot study compares the proteome of primary CRC and patient-matched CRC-LM. The applied protocol allows a reproducible and straightforward identification and quantification of over 2,600 proteins within the dissected tumorous tissue. Subsequent unsupervised clustering reveals distinct proteome biologies of the primary CRC and the corresponding CRC-LM. Statistical analysis yields multiple differentially abundant proteins in either primary CRC or their corresponding liver metastases. A more detailed analysis of dysregulated biological processes suggests an active immune response in the liver metastases, including several proteins of the complement system. Proteins with structural roles, e.g. cytoskeleton organization or cell junction assembly appear to be less prominent in liver metastases as compared to primary CRC. Immunohistochemistry corroborates proteomic high expression levels of metabolic proteins in CRC-LM. We further assessed how the in vitro inhibition of two in CRC-LM enriched metabolic proteins affected cell proliferation and chemosensitivity. The presented proteomic investigation in a small clinical cohort promotes a more comprehensive understanding of the distinct proteome biology of primary CRC and their corresponding liver metastases.

The Therapeutic Potential of Tackling Tumor-Induced Dendritic Cell Dysfunction in Colorectal Cancer

Colorectal cancer (CRC) is the third most diagnosed malignancy and the second leading cause of cancer-related deaths worldwide. Locally advanced and metastatic disease exhibit resistance to therapy and are prone to recurrence. Despite significant advances in standard of care and targeted (immuno)therapies, the treatment effects in metastatic CRC patients have been modest. Untreatable cancer metastasis accounts for poor prognosis and most CRC deaths. The generation of a strong immunosuppressive tumor microenvironment (TME) by CRC constitutes a major hurdle for tumor clearance by the immune system. Dendritic cells (DCs), often impaired in the TME, play a critical role in the initiation and amplification of anti-tumor immune responses. Evidence suggests that tumor-mediated DC dysfunction is decisive for tumor growth and metastasis initiation, as well as for the success of immunotherapies. Unravelling and understanding the complex crosstalk between CRC and DCs holds promise for identifying key mechanisms involved in tumor progression and spread that can be exploited for therapy. The main goal of this review is to provide an overview of the current knowledge on the impact of CRC-driven immunosuppression on DCs phenotype and functionality, and its significance for disease progression, patient prognosis, and treatment response. Moreover, present knowledge gaps will be highlighted as promising opportunities to further understand and therapeutically target DC dysfunction in CRC. Given the complexity and heterogeneity of CRC, future research will benefit from the use of patient-derived material and the development of in vitro organoid-based co-culture systems to model and study DCs within the CRC TME.

BMP4 and PHLDA1 are plausible drug-targetable candidate genes for KRAS G12A-, G12D-, and G12V-driven colorectal cancer

Despite the frequent detection of KRAS driver mutations in patients with colorectal cancer (CRC), no effective treatments that target mutant KRAS proteins have been introduced into clinical practice. In this study, we identified potential effector molecules, based on differences in gene expression between CRC patients carrying wild-type KRAS (n = 390) and those carrying KRAS mutations in codon 12 (n = 240). CRC patients with wild-type KRAS harboring mutations in HRAS, NRAS, PIK3CA, PIK3CD, PIK3CG, RALGDS, BRAF, or ARAF were excluded from the analysis. At least 11 promising candidate molecules showed greater than two-fold change between the KRAS G12 mutant and wild-type and had a Benjamini-Hochberg-adjusted P value of less than 1E-08, evidence of significantly differential expression between these two groups. Among these 11 genes examined in cell lines transfected with KRAS G12 mutants, BMP4, PHLDA1, and GJB5 showed significantly higher expression level in KRAS G12A, G12D, and G12V transfected cells than in the wild-type transfected cells. We expect that this study will lead to the development of novel treatments that target signaling molecules functioning with KRAS G12-driven CRC.

Conversion therapy combined with individualized surgical treatment strategy improves survival in patients with colorectal cancer liver metastases

OBJECTIVE

To explore surgical treatment strategies for patients with liver metastases from colorectal cancer (CRLM), and analyze the prognosis and influencing factors.

METHODS

The clinical data of 156 inpatients with CRLM admitted to our hospital from January 2009 to June 2019 were retrospectively analyzed. Patients were divided into initially resectable group (80 cases) and initially unresectable group (76 cases). For patients with initially unresectable CRLM, conversion therapy (chemotherapy plus targeted therapy) combined with individualized surgical treatment strategy was used. The individualized surgical treatment strategy mainly included hepatectomy combined with ablation. Portal vein ligation and staged resection were adopted according to the patients' specific conditions. All patients were followed up until death. The Kaplan-Meier method and Log-rank test were used for survival analysis.

RESULTS

Median overall survival (OS) time of patients in the initially resectable group and initially unresectable group were 36 months and 17 months, respectively (P = 0.001). Median OS time of 24 patients who underwent surgical resection after successful conversion therapy was significantly longer than that of 52 patients with unsuccessful conversion therapy (20 months versus 15 months, respectively, P = 0.034). Univariate analysis showed that a maximum diameter of liver metastases < 6 cm and a number of metastases ≤ 4 were independent factors associated with successful conversion therapy. According to patients' specific conditions, 6 cases accepted hepatectomy combined with ablation, and 1 case accepted portal vein ligation and staged resection.

CONCLUSION

Treatment of patients with CRLM should follow the principles of standardization and individualization. For patients with initially unresectable CRLM, successful conversion therapy should be pursued whenever possible. The maximum size and number of liver metastases were significantly associated with successful conversion therapy. Surgical resection-based comprehensive treatment is key.

Nomogram for predicting occurrence and prognosis of liver metastasis in colorectal cancer: a population-based study

PURPOSE

This study aimed to investigate the prevalence, risk, and prognostic factors for synchronous liver metastasis (LM) in colorectal cancer (CRC) and to construct nomogram for predicting occurrence and prognosis of synchronous LM.

METHODS

A total of 203,998 CRC patients who were registered in the SEER database between 2010 and 2016 were included. Logistic regression was used to analyze risk factors and Kaplan-Meier was used to estimate the overall survival of CRC patients with LM. Potential prognostic factors were identified by multivariable Cox regression. For predicting the risk for development and prognosis in CRC patients with LM, we constructed nomogram and the predictive performance was estimated by the receiver operating characteristics cure, the concordance index, and calibration curve.

RESULTS

In total, 15.3% of the CRC patients (N = 31,288) had synchronous LM. Male gender, black, uninsured status, left colon, T4/T1, and bone and lung metastases were positively associated with synchronous LM risk. The 1-year, 3-year, and 5-year overall survival rate was 49.1%, 18.4%, and 9.2%, respectively. Older age, male gender, black, uninsured status, poor histological differentiation, lymphatic metastasis, T4/T1, positive carcinoembryonic antigen, and lung, bone, and brain metastases were associated with the overall survival. Nomogram was constructed to predict the development and prognosis of synchronous LM and both of them were proved to have good calibration and discrimination.

CONCLUSION

LM is highly prevalent in CRC patients. Nomogram basing on the risk and prognostic factors for synchronous LM was proved to have good performance for predicting the probability of LM occurrence and prognosis.

Gene and protein expression of mTOR and LC3 in hepatocellular carcinoma, colorectal liver metastasis and "normal" liver tissues

The physiological role of autophagy in the progression of liver diseases is still debated. To understand the clinical relevance of autophagy in primary e secondary hepatic tumors, we analyzed the expression of mTOR (mammalian target of rapamycin), a key regulator of autophagy; Raptor (regulatory-associated protein of mTOR); ULK1 (Unc-51 like kinase 1) determinant in the autophagy initiation; LC3 (microtubule-associated protein 1A/1B-light chain 3), a specific marker of autophagosomes; and p62, a selective autophagy receptor. Samples from subjects with chronic hepatitis (n.58), cirrhosis (n.12), hepatocellular carcinoma (HCC, n.56), metastases (n.48) from colorectal cancer and hyperplasia or gallbladder stones (n.7), the latter considered as controls, were examined. Gene expression analysis was carried out in n.213 tissues by absolute q-PCR, while protein expression by Western Blot in n.191 lysates, including tumoral, surrounding tumoral and normal tissues. Nonparametric statistical tests were used for comparing expression levels in the above-mentioned groups. Subgroup analysis was performed considering viral infection and chemotherapy treatment. The mTOR transcriptional level was significantly lower in metastases compared to HCC (P = 0.0001). p-mTOR(Ser2448) and LC3II/LC3I protein levels were significantly higher in metastases compared to HCC (P = 0.008 and P<0.0001, respectively). ULK(Ser757) levels were significantly higher in HCC compared to metastases (P = 0.0002) while the HCV- and HBV- related HCC showed the highest p62 levels. Chemotherapy induced a down-regulation of the p-mTOR(Ser2448) in metastases and in non-tumor surrounding tissues in treated patients compared to untreated (P = 0.001 and P = 0.005, respectively). Conclusions: the different expression of proteins considered, owning their interaction and diverse tissue microenvironment, indicate an impairment of the autophagy flux in primary liver tumors that is critical for the promotion of tumorigenesis process and a coexistence of autophagy inhibition and activation mechanisms in secondary liver tumors. Differences in mTOR and LC3 transcripts emerged in tumor-free tissues, therefore particular attention should be considered in selecting the control group.

Antitumor properties of arsenic trioxide-loaded CalliSpheres® microspheres by transarterial chemoembolization in VX2 liver tumor rabbits: suppression of tumor growth, angiogenesis, and metastasis and elongation of survival

This study aimed to investigate the antitumor effect of arsenic trioxide (ATO)-loaded CalliSpheres^® microspheres (CSM) by transarterial chemoembolization (TACE) in rabbits with VX2 liver tumors. A total of 120 VX2 liver tumor rabbits were randomized into four groups (N = 30 for each group), which received ATO-loaded CSM by TACE (CSM-ATO group), ATO by conventional TACE (cTACE-ATO group), transcatheter arterial embolization using CSM (TAE-CSM group), and saline arterial injection (control group). Five rabbits in each group were sacrificed at 12 h, 3 d, 7 d and 14 d, and then tumor proliferation, apoptosis, and angiogenesis/epithelial-mesenchymal transition (EMT) markers were detected. Tumor volume, metastasis status and ascites were assessed at 14 d. Ten rabbits in each group were observed until death for accumulating survival calculation. Tumor volume and ascites were decreased in the CSM-ATO group compared to the cTACE-ATO and TAE-CSM groups. Pulmonary, abdominal wall and omentum metastases were reduced while accumulating survival was increased in the CSM-ATO group compared to the TAE-CSM group. However, no difference in metastasis foci or survival between the CSM-ATO and cTACE-ATO groups was discovered. Meanwhile, tumor apoptosis was promoted while proliferation was suppressed in the CSM-ATO group compared to the cTACE-ATO and TAE-CSM groups. Additionally, HIF-1α, VEGF and microvessel density were decreased in the CSM-ATO group compared to the cTACE-ATO and TAE-CSM groups. Additionally, twist, N-cadherin, vimentin and MMP-9 were reduced while E-cadherin was enhanced in the CSM-ATO group compared to the cTACE-ATO and TAE-CSM groups. In conclusion, ATO-loaded CSM by TACE suppressed tumor growth, angiogenesis, and metastasis and elongated survival in VX2 liver tumor rabbits.

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.

Fibrosis-4 Index, a Noninvasive Fibrosis Marker, Predicts Survival Outcomes After Hepatectomy for Colorectal Cancer Liver Metastases

BACKGROUND

Liver fibrosis influences liver regeneration and surgical outcomes, and several noninvasive models based on laboratory data have been developed to predict liver fibrosis. This study was performed to determine whether the Fibrosis-4 (FIB-4) index, a noninvasive fibrosis marker, can predict the prognosis in patients with colorectal liver metastases (CRLM) undergoing hepatectomy.

METHODS

This retrospective study involved 193 consecutive patients with CRLM who underwent hepatectomy. The FIB-4 index was calculated by laboratory data and age before hepatectomy and before preoperative chemotherapy. The FIB-4 cut-off was determined using survival classification and regression tree analysis. Patients were divided into two groups (high and low FIB-4 index), and post-hepatectomy overall survival (OS) and recurrence-free survival (RFS) were investigated.

RESULTS

In total, 193 patients were evaluated. Chemotherapy before hepatectomy was performed in 105 (54.4%) patients. A high FIB-4 index (> 2.736) was found in 39 (20.2%) patients. OS was significantly shorter in patients with a high FIB-4 index than those with a low FIB-4 index in the univariate (45.9 vs. 74.4 months, log-rank p = 0.007) and multivariate analysis (hazard ratio 2.28, 95% confidence interval 1.39-3.74; p = 0.001). Among patients who received chemotherapy before hepatectomy, those with a high FIB-4 index had significantly shorter RFS (6.9 vs. 45.3 months, log-rank p = 0.047) and OS (23.9 vs. 55.0 months, log-rank p = 0.003) than those with a low FIB-4 index. This association was also confirmed by multivariate analysis (hazard ratio 4.28, 95% confidence interval 1.46-12.6; p = 0.008).

CONCLUSION

Both the preoperative and prechemotherapy FIB-4 index can predict long-term outcomes after hepatectomy in patients with CRLM.

Conversion Chemotherapy With a Modified FLOX Regimen for Borderline or Unresectable Liver Metastases From Colorectal Cancer: An Alternative for Limited-Resources Settings

PURPOSE

Conversion chemotherapy is often used for borderline or unresectable (B/U) liver metastases from colorectal cancer (CRC) with the aim of achieving resectability. Although intensive and costly regimens are often used, the best regimen in this scenario remains unclear. We aimed to evaluate the outcomes of patients with B/U liver metastases from CRC treated with conversion chemotherapy with the modified fluorouracil, leucovorin, and oxaliplatin (mFLOX) regimen followed by metastasectomy.

METHODS

We performed a single-center retrospective analysis of patients with B/U liver metastases from CRC treated with chemotherapy with the mFLOX regimen followed by surgery. B/U disease was defined as at least one of the following: more than four lesions, involvement of hepatic artery or portal vein, or involvement of biliary structure.

RESULTS

Fifty-four consecutive patients who met our criteria for B/U liver metastases were evaluated. Thirty-five patients (64%) had more than four liver lesions, 16 (29%) had key vascular structure involvement, and 16 (29%) had biliary involvement. After chemotherapy, all patients had surgery and 42 (77%) had R0 resection. After a median follow-up of 37.2 months, median progression-free survival (PFS) was 16.9 months and median overall survival (OS) was 68.3 months. R1-R2 resections were associated with worse PFS and OS compared with R0 resection (PFS: hazard ratio, 2.65; P = .007; OS: hazard ratio, 2.90; P = .014).

CONCLUSION

Treatment of B/U liver metastases from CRC with conversion chemotherapy using mFLOX regimen followed by surgical resection was associated with a high R0 resection rate and favorable survival outcomes. On the basis of our results, we consider mFLOX a low-cost option for conversion chemotherapy among other options that have been proposed.

Response to preoperative chemotherapy: impact of change in total burden score and mutational tumor status on prognosis of patients undergoing resection for colorectal liver metastases

BACKGROUND

Progression of colorectal liver metastasis (CRLM) on preoperative chemotherapy has been associated with a worse prognosis compared with patients who have responsive disease. Defining response can be challenging as traditional criteria largely assess only tumor size.

METHODS

Patients who underwent hepatectomy between 2010 and 2017 were identified using a multi-centric database. This study aimed to define the impact of preoperative chemotherapy response relative to initial tumor burden score (TBS) and determine impact of clinico-pathological variables on overall survival (OS).

RESULTS

Among 784 patients who received preoperative chemotherapy, the regimen was oxaliplatin- (66%) or irinotecan-based (34%). Among patients with a TBS<6 at diagnosis, genetic status was the most important prognostic variable. Patients with a TBS<6, 5-year OS was 55%, 35%, and 0% for patients with KRAS/NRAS/BRAF wild-type, KRAS/NRAS, and BRAF mutations, respectively. Among patients who presented with CRLM with a TBS≥6, only Δ-TBS was prognostically important and patients with a Δ-TBS ≥ -10% had a 5-year OS of 27% compared with 49% for patients with a Δ-TBS < -10%.

CONCLUSIONS

Prognostic stratification of patients with CRLM receiving preoperative chemotherapy should be multi-faceted and include consideration of initial tumor burden, change in tumor burden due to chemotherapy, and tumor genetic status.

Baseline 3D-ADC outperforms 2D-ADC in predicting response to treatment in patients with colorectal liver metastases

OBJECTIVES

To examine the value of baseline 3D-ADC and to predict short-term response to treatment in patients with hepatic colorectal metastases (CLMs).

METHODS

Liver MR images of 546 patients with CLMs (2008-2015) were reviewed retrospectively and 68 patients fulfilled inclusion criteria. Patients had received systemic chemotherapy (n = 17), hepatic trans-arterial chemoembolization or TACE (n = 34), and ⁹⁰Y radioembolization (n = 17). Baseline (pre-treatment) 3D-ADC (volumetric) of metastatic lesions was calculated employing prototype software. RECIST 1.1 was used to assess short-term response to treatment. Prediction of response to treatment by baseline 3D-ADC and 2D-ADC (ROI-based) was also compared in all patients.

RESULTS

Partial response to treatment (minimum 30% decrease in tumor largest transverse diameter) was seen in 35.3% of patients; 41.2% with systemic chemotherapy, 32.4% with TACE, and 35.3% with ⁹⁰Y radioembolization (p = 0.82). Median baseline 3D-ADC was significantly lower in responding than in nonresponding lesions. Area under the curve (AUC) of 3D-ADC was 0.90 in ⁹⁰Y radioembolization patients, 0.88 in TACE patients, and 0.77 in systemic chemotherapy patients (p < 0.01). Optimal prediction was observed with the 10th percentile of ADC (1006 × 10^-6 mm²/s), yielding sensitivity and specificity of 77.4% and 91.3%, respectively. 3D-ADC outperformed 2D-ADC in predicting response to treatment (AUC; 0.86 vs. 0.71; p < 0.001).

CONCLUSION

Baseline 3D-ADC is a highly specific biomarker in predicting partial short-term response to treatment in hepatic CLMs.

KEY POINTS

• Baseline 3D-ADC is a highly specific biomarker in predicting response to different treatments in hepatic CLMs. • The prediction level of baseline ADC is better for⁹⁰Y radioembolization than for systemic chemotherapy/TACE in hepatic CLMs. • 3D-ADC outperforms 2D-ADC in predicting short-term response to treatment in hepatic CLMs.