Multidisciplinary approach of colorectal liver metastases. Clin Transl Oncol. 2011;13:721-727. [PMID: 21975333 DOI: 10.1007/s12094-011-0722-x]

Tumor-infiltrating immune cells based TMEscore and related gene signature is associated with the survival of CRC patients and response to fluoropyrimidine-based chemotherapy

Background

Tumor-infiltrating immune cells (TIICs) are associated with chemotherapy response. This study aimed to explore the prognostic value of a TIIC-related tumor microenvironment score (TMEscore) in patients with colorectal cancer (CRC) who underwent chemotherapy and construct a TMEscore-related gene signature to determine its predictive value.

Methods

Gene profiles of patients who underwent fluoropyrimidine-based chemotherapy were collected, and their TIIC fractions were calculated and clustered. Differentially expressed genes (DEGs) between clusters were used to calculate the TMEscore. The association between the TMEscore, chemotherapy response, and survival rate was analyzed. Machine learning methods were used to identify key TMEscore-related genes, and a gene signature was constructed to verify the predictive value.

Results

Two clusters based on the TIIC fraction were identified, and the TMEscore was calculated based on the DEGs of the two clusters. The TMEscore was higher in patients who responded to chemotherapy than in those who did not, and was associated with the survival rate of patients who underwent chemotherapy. Three machine learning methods, support vector machine (SVM), decision tree (DT), and Extreme Gradient Boosting (XGBoost), identified three TMEscore-related genes (ADH1C, SLC26A2, and NANS) associated with the response to chemotherapy. A TMEscore-related gene signature was constructed, and three external cohorts validated that the gene signature could predict the response to chemotherapy. Five datasets and clinical samples showed that the expression of the three TMEscore-related genes was increased in tumor tissues compared to those in control tissues.

Conclusions

The TIIC-based TMEscore was associated with the survival of CRC patients who underwent fluoropyrimidine-based chemotherapy, and predicted the response to chemotherapy. The TMEscore-related gene signature had a better predictive value for response to chemotherapy than for survival.

Chances, challenges and outcomes of patients with complex bilobar colorectal liver metastases approached by a combined multimodal therapy with liver resection and local ablative therapy

BACKGROUND AND OBJECTIVES

In treatment of colorectal liver metastases (CRC-LM), liver surgery combined with systemic therapies and local ablation (LAT) allows improved survival. This study aims at the outcomes of patients with complex bilobar CRC-LM who were intended to undergo multimodal therapy with liver resection and LAT.

METHODS

Forty-three CRC-LM patients with recommendation for multimodal treament were extracted from 5878 tumor board decisions between 2014 and 2017. Outcome variables included patient survival, as well as completion of hepatic clearance. Prognostic factors were identified by correlation and a Cox proportional hazards model.

RESULTS

Out of 43 patients only 23 achieved complete clearance of CRC-LM. One- and 3-year overall survival of patients with cleared liver disease was 100% and 91.7%, respectively, as compared to 83.8% and 12.1%. Incomplete hepatic clearance was the strongest independent risk factor for overall survival (hazards ratio [HR], 5.86; p = .009). Risk factors for incomplete clearance were higher age (r = .34; p = .026), comorbidities (r = .40; p = .008), major complications (r = .34; p = .024), and prolonged intensive care unit stay (r = .41; p = .017).

CONCLUSION

Completion of hepatic clearance is crucial to achieve long-term survival in patients with complex bilobar CRC-LM. Careful patient selection and treatment planning should avoid treatment failure before completing the intended therapy plan when multimodal treatments are planned.

Exosome-transmitted miRNA-335-5p promotes colorectal cancer invasion and metastasis by facilitating EMT via targeting RASA1

Exosomal microRNA (miRNA) secretion has been characterized as a vital factor in intercellular communication among cancer cells. However, little is known about cancer-secreted miRNAs specifically involved in metastasis of colorectal cancer (CRC). Here, we found that exosomes derived from metastatic CRC cell line SW620 promoted migration, invasion, and epithelial-mesenchymal transition (EMT) of CRC cells. The profiling of exosome miRNAs revealed that microRNA (miR)-335-5p was highly expressed in exosomes from metastatic SW620 cells compared to those derived from primary SW480 cells. miR-335-5p was transmitted from metastatic SW620 cells to CRC cells via exosomes and promoted migration, invasion, and EMT of CRC cells. Moreover, exosome-transmitted miRNA-335-5p promotes CRC cell invasion and metastasis by facilitating EMT via targeting RAS p21 protein activator 1 (RASA1). Overexpression of RASA1 abolished the promotive effects of exosomal miR-335-5p on CRC cell migration, invasion, and EMT. Collectively, our data revealed that exosomal miR-335-5p derived from metastatic CRC cells promotes CRC cell invasion and metastasis by facilitating EMT via targeting RASA1, which may serve as a potential therapeutic target for CRC metastasis.

SATB2 Shows Different Profiles Between Appendiceal Adenocarcinomas Ex Goblet Cell Carcinoids and Appendiceal/Colorectal Conventional Adenocarcinomas: An Immunohistochemical Study With Comparison to CDX2

Background

Special AT-rich sequence-binding protein 2 (SATB2) is a novel marker for colorectal adenocarcinomas but little is known about its expression in appendiceal adenocarcinomas. We aim to investigate SATB2 in these tumors and colorectal adenocarcinomas with comparison to CDX2.

Methods

Immunohistochemical stains for SATB2 and CDX2 were performed in 49 appendiceal adenocarcinomas (23 conventional, 26 adenocarcinoma ex goblet cell carcinoids (AdexGCCs)) and 57 colorectal adenocarcinomas. Their expression was correlated with tumor differentiation and growth patterns.

Results

SATB2 staining was positive in 26/26 (100%) appendiceal AdexGCCs and 15/23 (65%) appendiceal conventional adenocarcinomas (P = 0.001). Their mean percentage of SATB2-positive cells was 93% and 34%, respectively (P < 0.0001). CDX2 staining was seen in 26/26 (100%) AdexGCCs and 22/23 (96%) appendiceal conventional adenocarcinomas (P = 0.4694). SATB2 and CDX2 showed similar staining in AdexGCCs but CDX2 labeled more tumor cells than SATB2 in conventional adenocarcinomas (mean 84% vs. 34%, P < 0.0001). SATB2 and CDX2 staining was seen in 82% (47/57) and 96% (55/57) colorectal adenocarcinomas, respectively (P = 0.01). The mean percentage of cells positive for SATB2 and CDX2 was 48% and 91%, respectively (P < 0.00001). Decreased SATB2 immunoreactivity was associated with non-glandular differentiation particularly signet ring cells in colorectal (P = 0.001) and appendiceal conventional adenocarcinomas (P = 0.04) but not in appendiceal AdexGCCs.

Conclusions

SATB2 is a highly sensitive marker for appendiceal AdexGCCs with similar sensitivity as CDX2. In colorectal and appendiceal conventional adenocarcinomas, SATB2 is not as sensitive as CDX2 and its immunoreactivity is dependent on tumor differentiation.

Radioembolization treatment for liver metastases

The liver is an organ that, due to vascularisation and functions, is prone to metastases. Most liver metastases are observed in cases of gastrointestinal cancers in: stomach, colon, gallbladder, and bile ducts. Metastatic lesions are also observed in lung, breast, thyroid, kidney, and pancreatic cancer. One of the best known and most effective ways of liver lesion treatment is Metastasectomy. Unfortunately, lesions are frequently inoperable. Apart from chemotherapy, it is possible to apply local treatment such as TACE (trans-arterial chemoembolisation), RFA (Radio Frequency Ablation), and SBRT (Stereotactic Body Radiation Therapy). One of the newest methods of inoperable lesion treatment is radioembolisation (SIRT). Intravascular administration of microspheres containing radioisotope 90Y allows delivery of a higher dose of radiation directly to the tumour than traditional radiation with an external beam, while maintaining a small dose to healthy liver methods. Conducted clinical studies confirm the efficacy and safety of SIRT. It is an interesting alternative to other ways of treatment.

Upregulation of microRNA-125b by G-CSF promotes metastasis in colorectal cancer

Although there are reports of miR-125b being dysregulated in colorectal cancer (CRC) and associated with CRC progression, little is known about its intrinsic regulatory mechanisms. Here we detected the expression of miR-125b in CRC tissues, subsequently investigated the effect of miR-125b on the proliferation, apoptosis, cell cycle and metastasis on CRC cells. Our results showed that the expression of miR-125b was significantly decreased in CRC tissues comparing to adjacent tissues. However, with the stimulation of Granulocyte colony-stimulating factor (G-CSF), which was highly expressed in CRC tissues, the expression of miR-125b could be improved. Analysis of patient samples revealed that miR-125b presented a clear association with poor differentiation, positive lymph node metastasis, and advanced TNM stage. Overexpression of miR-125b inhibited cell proliferation, triggered G2/M cell cycle arrest, induced subsequent apoptosis, and promoted cell migration and invasion. Moreover, luciferase reporter assays and western blot clarified that the myeloid cell leukemia 1 (MCL1) was a direct target of miR-125b. Thus overexpression of MCL1 attenuated the pro-metastasis function of miR-125b in CRC cell lines. In addition, the protein expression level of MCL1 was decreased in CRC tissues from patients with positive lymph node metastasis, which had high miR-125b expression. Collectively, our study suggested that miR-125b induced by G-CSF plays a promoting role in the metastasis of CRC by targeting MCL1, which may serve as a novel therapeutic target for CRC metastasis.

Prognostic prediction by liver tissue proteomic profiling in patients with colorectal liver metastases

AIM

To obtain proteomic profiles in patients with colorectal liver metastases (CRLM) and identify the relationship between profiles and the prognosis of CRLM patients.

MATERIALS & METHODS

Prognosis prediction (favorable or unfavorable according to Fong's score) by a classification and regression tree algorithm of surface-enhanced laser desorption/ionization TOF-MS proteomic profiles from cryopreserved CRLM (patients) and normal liver tissue (controls).

RESULTS

The protein peak 7371 m/z showed the clearest differences between CRLM and control groups (94.1% sensitivity, 100% specificity, p < 0.001). The algorithm that best differentiated favorable and unfavorable groups combined 2970 and 2871 m/z protein peaks (100% sensitivity, 90% specificity).

CONCLUSION

Proteomic profiling in liver samples using classification and regression tree algorithms is a promising technique to differentiate healthy subjects from CRLM patients and to classify the severity of CRLM patients.

MicroRNA-375 suppresses human colorectal cancer metastasis by targeting Frizzled 8

microRNAs are aberrantly expressed during the development and progression of a variety of human cancers, including colorectal cancer (CRC). Of these microRNAs, microRNA-375 (miR-375) was previously observed to be downregulated in human colorectal cancer(CRC) plasma and tissues, but its functions are largely unknown. Here, we investigated the impact of miR-375 on CRC metastasis. Specifically, miR-375 expression was significantly decreased in human CRC tissues compared with their matched noncancerous tissues (NCTs), and low levels of miR-375 predicted tumor metastatic potential. The up-regulation of miR-375 suppressed colorectal cancer cell migration and invasion in vitro and reduced tumor metastases in murine models established by both orthotopic implantation and spleen injection. Furthermore, we identified Frizzled 8 (FZD8) as a direct target of miR-375 in CRC, and miR-375 negatively regulated Wnt/β-catenin signaling by suppressing FZD8. More importantly, FZD8 expression inversely correlated with overall survival in human CRC patients and is a likely independent predictor of survival. Therefore, we concluded that miR-375 functions as a tumor-suppressive microRNA by directly acting upon FZD8, which may serve as a new therapeutic target to inhibit tumor metastasis in CRC.

Colorectal cancer metastatic to the brain: analysis of prognostic factors and impact of KRAS mutations on presentation and outcome

BACKGROUND

Treatment concepts for metastatic colorectal cancer continue to evolve. While the presence of RAS mutations impacts systemic therapy, little is known about the influence of such mutations in patients with brain metastases.

PATIENTS AND METHODS

Pooled retrospective analysis was conducted of 57 patients with brain metastases from colorectal cancer treated in two different institutions (2005-2013).

RESULTS

The only mutations analyzed in a relatively large subgroup were KRAS mutations (14 wild type, 12 mutated). Mutation status was not associated with baseline characteristics such as number or location of metastases, and did not impact prognosis. Three factors were significantly associated with survival in multivariate analysis: Karnofsky Performance Status (KPS), management strategy, and systemic treatment. Median survival was 0.6 months with best supportive care, 3.0 months with initial whole-brain radiotherapy (WBRT), and 12.7 months if initial treatment included surgery or stereotactic radiosurgery (SRS), p = 0.0001. The survival difference between the WBRT and surgery/SRS groups was largest in patients with KPS 80-100.

CONCLUSION

Effective local treatment was a prerequisite for improved survival. The only significant prognostic baseline factor was KPS, which forms the basis of the diagnosis-specific graded prognostic assessment (DS-GPA) score. Thus, our results validate the DS-GPA in this patient population. So far, neither this nor other studies suggest a clinically important impact of KRAS mutations beyond their previously reported association with development of brain metastases. Studies focusing on patients who develop brain metastases early during the course of metastatic disease might be warranted, because the influence of different systemic therapies might be larger in this subgroup.

Anti-angiogenic therapies for metastatic colorectal cancer: Current and future perspectives

Colorectal cancer (CRC) is the fourth most commonly diagnosed cancer and the second leading cause of cancer death in both men and women in the United States, with about 142820 new cases and 50830 deaths expected in 2013. Metastatic disease (mCRC) remains a challenge for oncologists worldwide due to its potential comorbidities. Recently, chemotherapy regimens containing 5-fluorouracil, leucovorin, oxaliplatin and irinotecan combinations are a standard of care in the metastatic disease. Currently, biological therapies involving vascular endothelial growth factor and epidermal growth factor receptor pathways, such as bevacizumab and cetuximab, have emerged as good option for improving mCRC patient survival. Now, aflibercept plus standard chemotherapy has also been approved in second line regimen for mCRC patients. Our review will discuss novel biological drugs and their indications for mCRC patients and will bring future perspectives in this regard.

Increased growth of colorectal liver metastasis following partial hepatectomy

Nearly 50 % of colorectal cancer (CRC) patients develop liver metastases with liver resection being the only option to cure patients. Residual micrometastases or circulating tumor cells are considered a cause of tumor relapse. This work investigates the influence of partial hepatectomy (PH) on the growth and molecular composition of CRC liver metastasis in a syngeneic rat model. One million CC531 colorectal tumor cells were implanted via the portal vein in WAG/Rij rats followed by a 30 % PH a day later. Control groups either received tumor cells followed by a sham-operation or were injected with a buffer solution followed by PH. Animals were examined with magnetic resonance imaging (MRI) and liver tissues were processed for immunolabeling and PCR analysis. One-third PH was associated with an almost threefold increase in relative tumor mass (MRI volumetry: 2.8-fold and transcript levels of CD44: 2.3-fold). Expression of molecular markers for invasiveness and aggressiveness (CD49f, CXCR4, Axin2 and c-met) was increased following PH, however with no significant differences when referring to the relative expression levels (relating to tumor mass). Liver metastases demonstrated a significantly higher proliferation rate (Ki67) 2 weeks following PH and cell divisions also increased in the surrounding liver tissue. Following PH, the stimulated growth of metastases clearly exceeded the compensation in liver volume with long-lasting proliferative effects. However, the distinct tumor composition was not influenced by liver regeneration. Future investigations should focus on the inhibition of cell cycle (i.e. systemic therapy strategies, irradiation) to hinder liver regeneration and therefore restrain tumor growth.