VEGF levels and the angiogenic potential of the microenvironment can affect surgical strategy for colorectal liver metastasis

Disappearing Colorectal Liver Metastases: Do We Really Need a Ghostbuster?

The development of new systemic treatment strategies has resulted in a significant increase in the response rates of colorectal liver metastases (CRLM) in the last few years. Although the radiological response is a favorable prognostic factor, complete shrinkage of CRLM, known as disappearing liver metastases (DLM), presents a therapeutic dilemma, and proper management is still debated in the literature. In fact, DLM is not necessarily equal to cure, and when resected, pathological examination reveals in more than 80% of patients a variable percentage of the tumor as residual disease or early recurrence in situ. Moreover, while a higher incidence of intrahepatic recurrence is documented in small series when surgery is avoided, its clinical significance for long-term OS is still under investigation. In light of this, a multidisciplinary approach and, in particular, radiologists’ role is needed to assist the surgeon in the management of DLM, thanks to emerging technology and strategy. Therefore, the aim of this review is to provide an overview of the DLM phenomenon and current management.

Surgery on primary tumor shows survival benefit in selected stage IV colon cancer patients: A real-world study based on SEER database

Objectives: Most patients with stage IV colon cancer did not have the opportunity for curative surgery, only selected patients could benefit from surgery. This study aimed to determine whether surgery on the primary tumor (SPT) should be performed in patients with stage IV colon cancer and how to select patients for SPT.

Methods: This study included 48,933 patients with stage IV colon cancer who were identified in the Surveillance, Epidemiology and End Results (SEER) database between 1998 and 2015. Propensity score matching (PSM) analysis was adopted to balance baseline differences between SPT and non-surgery groups. Kaplan-Meier (K-M) curves were utilized to compare the overall survival (OS). Prognostic nomograms were generated to predict survival based on pre- and post-operative risk factors. Patients were divided into low, middle, and high mortality risk subsets for OS by X-tile analyses based on scores derived from above nomograms.

Results: Patients with SPT had a significantly longer OS than those without surgery, regardless of the metastatic sites and diagnostic years. Nomograms, according to the pre- and post-operative risk factors, showed moderate discrimination (all C-indexes above 0.7). Based on X-tile analyses, low mortality risk subset (post-operative score ≤ 22.3, preoperative score ≤ 9.7) recommended for SPT, and high mortality risk was not.

Conclusions: SPT led to prolonged survival in stage IV colon cancer. Our nomograms would help to select suitable patients for SPT.

Meta-analysis of safety and efficacy of antiangiogenic drug aflibercept for metastatic colorectal cancer

BACKGROUND

Numerous studies have reported that the combination of arbacicept and FOLFOX4/FOLFIRI regimen can more effectively treat metastatic colon cancer (mCRC). In the preset study, we performed a meta-analysis to assess the efficacy and safety of arbacicept for mCRC to provide an evidence-based medicine related basis for the application of this drug.

AIM

To systematically assess the clinical efficacy and safety of aflibercept for patients with metastatic colorectal cancer (mCRC) by meta-analysis.

METHODS

Controlled trials that involved aflibercept with FOLFOX4/FOLFIRI regimen for treating mCRC from January 2009 to January 2019 were searched, covering China HowNet database, Weipu database, Wanfang database, China Biomedical Literature database, PubMed, as well as The Cochrane Library and EMBASE. The retrieved studies were evaluated according to the Cochrane Systematic Evaluation Manual. A meta-analysis was performed with RevMan5.3 software and 95% confidence interval (CI) estimation.

RESULTS

Five studies were included. The results of the meta-analysis showed that the 3-year overall survival rate and 3-year recurrence-free survival rate were significantly higher in the study group than in the control group (OR [odds ratio] = 0.52, 95%CI: 0.35-0.79, P = 0.002; OR = 0.63, 95%CI: 0.45-0.89, P = 0.008). Compared with the control group, the study group had fewer adverse events (OR = 0.58, 95%CI: 0.40-0.84, P = 0.004). Furthermore, the study group had a significantly lower incidence of diarrhea, leukopenia, loss of appetite, and nausea and vomiting than the control group (P < 0.05).

CONCLUSION

Aflibercept with FOLFOX4/FOLFIRI regimen has better efficacy and adverse event profile for treatment of refractory mCRC than FOLFOX4/FOLFIRI alone.

In-Depth Characterization of Mass Spectrometry-Based Proteomic Profiles Revealed Novel Signature Proteins Associated with Liver Metastatic Colorectal Cancers

Liver metastasis is the most common form of metastatic colorectal cancers during the course of the disease. The global change in protein abundance in liver metastatic colorectal cancers and its role in metastasis establishment have not been comprehensively analyzed. In the present study, fresh-frozen tissue samples including normal colon/localized/liver metastatic CRCs from each recruited patient were analyzed by quantitative proteomics using a multiplexed TMT labeling strategy. Around 5000 protein groups were quantified from all samples. The proteomic profile of localized/metastatic CRCs varied greatly from that of normal colon tissues; differential proteins were mainly from extracellular regions and participate in immune activities, which is crucial for the chronic inflammation signaling pathways in the tumor microenvironment. Further statistical analysis revealed 47 proteins exhibiting statistical significance between localized and metastatic CRCs, of which FILI1P1 and PLG were identified for the first time in proteomic data, which were highly associated with liver metastasis in CRCs.

Disappearing liver metastases: A systematic review of the current evidence

Advances in systemic chemotherapy have resulted in a significant increase in the reported response rates of colorectal liver metastases (CRLM) over time. Although radiologic response is usually prognostic of favorable outcomes, complete shrinkage of CRLM after chemotherapy, namely "disappearing liver metastases" (DLMs) poses significant therapeutic dilemmas. A systematic review of the literature was conducted to evaluate the existing evidence on the imaging and management of patients with DLMs using the PubMed (Medline), Embase and Cochrane library through December 21st, 2018. The following algorithm was used: "(disappearing OR vanishing OR missing OR (residual tiny)) AND ((liver OR hepatic) AND (metastasis OR metastases OR metastatic OR secondary))." From the 225 records retrieved, 15 studies were finally deemed eligible. A total of 479 patients with DLMs with a median age of 59.5 years (range, 30-83) were identified. Median number of DLM per patient ranged from 1 to 8.8. Median size of LMs prior to chemotherapy was 1.07 cm (range 0.3-3.5). The systemic treatment used to achieve DLMs included systemic chemotherapy alone (only 2 studies) or in combination with targeted agents (11 studies). The median number of chemotherapy cycles in the included studies was 7.8 (range 6-12). Identified factors predisposing to the development of DLM were small size (<2 cm), increased number of treatment cycles, oxaliplatin-based therapy, increased number of CRLM (≥3) and synchronous CRLM. Baseline and preoperative MRI with iv contrast showed the highest sensitivity for DLM detection. Fiducial placement facilitated pre- and intra-operative identification of DLM. Although resection of DLM decreased the local recurrence risk, there was no clearly demonstrated survival benefit after resecting all sites of disappearing lesions. Future randomized clinical trials are highly encouraged to provide strict, evidence-based recommendations for the treatment of patients with DLM.

Hepatic stellate cells promote angiogenesis via the TGF-β1-Jagged1/VEGFA axis

Hepatic stellate cells (HSCs) are activated by transforming growth factor (TGF)-β1 and function as mesenchymal cells in liver regeneration. Activated HSCs also have proangiogenic ability in vivo. In this study, knockin of the TGF-β1 gene caused mHSCs to transform into myofibroblasts (MFs) highly expressing Jagged1 and vascular endothelial growth factor A (VEGFA). These MFs promoted formation of capillary-like structures by human umbilical vein endothelial cells (HUVECs) in vitro, which was much reduced after blocking TGF-β1 signaling. Transplantation of TGF-β1-knockin mHSCs was followed by efficient engraftment into livers and accompanied by increased vascular organization and expression of Jagged1 and VEGFA compared with controls. Less hepatic angiogenesis and lower Jagged1 and VEGFA expression, was found in livers engrafted with TGF-β-R1-knockdown mHSCs. Increased vascularization improved liver function. The findings showed that mHSCs were regulated by TGF-β1 signaling to express Jagged1 and VEGFA, which were associated with hepatic angiogenesis, a novel mechanism of mHSC promotion of new vascular structures.

The increased number of tumor-associated macrophage is associated with overexpression of VEGF-C, plays an important role in Kazakh ESCC invasion and metastasis

Tumor associated macrophages (TAMs) play an important role in the growth, progression, and metastasis of tumors. The distribution of TAMs in Kazakh esophageal squamous cell carcinoma (ESCC) is not determined. We aimed to investigate the role of TAMs in the occurrence and progression of Kazakh ESCC. CD163 was used as the TAM marker, and immunohistochemistry (IHC) counts were used to quantify the density of TAMs in tumor nest and surrounding stroma. IHC staining was used to evaluate the expression of vascular endothelial growth factor C (VEGF-C) in Kazakh ESCC and cancer adjacent normal (CAN) tissues. The density of TAMs in Kazakh ESCCs tumor nest and stromal was significantly higher than that in CAN tissues. The increased number of CD163-positive TAMs in tumor nest and tumor stromal was positively associated with Kazakh ESCC lymph node metastasis and clinical stage progression. Meanwhile, the expression of VEGF-C in Kazakh ESCCs was significantly higher than that in CAN tissues. Overexpression of VEGF-C in Kazakh ESCCs was significantly associated with gender, depth of tumor invasion, lymph node metastasis and tumor clinical stage. The increased number of TAMs, either in the tumor nests or tumor stroma was positively correlated with the overexpression of VEGF-C, which may promote lymphangiogenesis and play an important role in the invasion and metastasis of Kazakh ESCC.

Potential role of High mobility group box 1 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and is characterized as a typical inflammation-related carcinoma. High mobility group box protein 1 (HMGB1), a non-histone DNA-binding protein, is identified as a potent proinflammatory mediator when presents extracellularly. Recently, a growing body of evidence indicates that HMGB1 plays a potential role in HCC, but many questions remain unanswered about the relationship between HMGB1 and HCC formation and development. This review focuses on the biological effect of HMGB1, and discusses the association of HMGB1 with HCC and potential use of strategies targeting HMGB1 in HCC treatment.

Chitosan oligosaccharides in combination with Agaricus blazei Murill extract reduces hepatoma formation in mice with severe combined immunodeficiency

Chitosan and Agaricus blazei Murill (ABM) extracts possess antitumor activities. The aim of the present study was to investigate whether chitosan, ABM extract or the two in combination were effective against tumors in tumor‑bearing mice. The mice were subcutaneously injected with SK-Hep 1 cells and were then were divided into the following six groups: Group 1, control group; group 2, chitosan 5 mg/kg/day; group 3, chitosan 20 mg/kg/day; group 4, ABM (246 mg/kg/day) and chitosan (5 mg/kg/day) combined; group 5, ABM (984 mg/kg/day) and chitosan (20 mg/kg/day) combined; and group 6, ABM (984 mg/kg/day). The mice were treated with the different concentrations of chitosan, ABM or combinations of the two for 6 weeks. The levels of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) and vascular endothelial growth factor (VEGF), and tissue histopathological features were examined in the surviving animals. Based on the results of the investigation, the treatments performed in groups 2, 3 and 4 were identified as being capable of reducing the weights of the tumors, however, group 4, which was treated with chitosan (5 mg/kg/day) in combination with ABM (246 mg/kg/day) was able to reduce the levels of GOT and VEGF. As a result, treatment with chitosan in combination with ABM may offer potential in cancer therapy and requires further investigation.

The importance of the tumor microenvironment in the therapeutic management of cancer

Tumor prognosis is generally defined by various tumor parameters. However, it is well known that paracrine, endocrine and cell-cell interactions between the tumor and its microenvironment contribute to its growth. The tumor microenvironment (TME) can also influence disease prognosis and is likely to be considered as an important prognostic factor. In addition, conventional therapies can influence the microenvironment and antitumor immunity. Similarly, the TME will influence the effectiveness of therapy. The purpose of this review is to demonstrate how TME is important in therapeutic management. Key interactions between TME and different cancer therapies as well as their current clinical consequences have been described. More research is needed to establish the important network between tumor cells and their environment to highlight their relationships with conventional therapies and develop global therapeutic strategies.

Hallmarks in colorectal cancer: Angiogenesis and cancer stem-like cells

Carcinogenesis is a multistep process that requires the accumulation of various genetic and epigenetic aberrations to drive the progressive malignant transformation of normal human cells. Two major hallmarks of carcinogenesis that have been described are angiogenesis and the stem cell characteristic of limitless replicative potential. These properties have been targeted over the past decade in the development of therapeutic treatments for colorectal cancer (CRC), one of the most commonly diagnosed and lethal cancers worldwide. The treatment of solid tumor cancers such as CRC has been challenging due to the heterogeneity of the tumor itself and the chemoresistance of the malignant cells. Furthermore, the same microenvironment that maintains the pool of intestinal stem cells that contribute to the continuous renewal of the intestinal epithelia also provides the necessary conditions for proliferative growth of cancer stem-like cells. These cancer stem-like cells are responsible for the resistance to therapy and cancer recurrence, though they represent less than 2.5% of the tumor mass. The stromal environment surrounding the tumor cells, referred to as the tumor niche, also supports angiogenesis, which supplies the oxygen and nutrients needed for tumor development. Anti-angiogenic therapy, such as with bevacizumab, a monoclonal antibody against vascular-endothelial growth factor, significantly prolongs the survival of metastatic CRC patients. However, such treatments are not completely curative, and a large proportion of patient tumors retain chemoresistance or show recurrence. This article reviews the current knowledge regarding the molecular phenotype of CRC cancer cells, as well as discusses the mechanisms contributing to their maintenance. Future personalized therapeutic approaches that are based on the interaction of the carcinogenic hallmarks, namely angiogenic and proliferative attributes, could improve survival and decrease adverse effects induced by unnecessary chemotherapy.

Targeting angiogenesis and tumor microenvironment in metastatic colorectal cancer: role of aflibercept

In the last decades, we have progressively observed an improvement in therapeutic options for metastatic colorectal cancer (mCRC) treatment with a progressive prolongation of survival. mCRC prognosis still remains poor with low percentage of 5-year survival. Targeted agents have improved results obtained with standard chemotherapy. Angiogenesis plays a crucial role in colorectal cancer growth, proliferation, and metastasization and it has been investigated as a potential target for mCRC treatment. Accordingly, novel antiangiogenic targeted agents bevacizumab, regorafenib, and aflibercept have been approved for mCRC treatment as the result of several phase III randomized trials. The development of a tumor permissive microenvironment via the aberrant expression by tumor cells of paracrine factors alters the tumor-stroma interactions inducing an expansion of proangiogenic signals. Recently, the VELOUR study showed that addition of aflibercept to FOLFIRI regimen as a second-line therapy for mCRC improved significantly OS, PFS, and RR. This molecule represents a valid second-line therapeutic option and its peculiar ability to interfere with placental growth factor (PlGF)/vascular endothelial growth factor receptor 1 (VEGFR1) axis makes it effective in targeting angiogenesis, inflammatory cells and in overcoming resistances to anti-angiogenic first-line treatment. Here, we discuss about Aflibercept peculiar ability to interfere with tumor microenvironment and angiogenic pathway.

Interleukin-12 prevents colorectal cancer liver metastases in mice

Interleukin (IL)-12 has emerged to be a prospective molecule for antitumor therapies with many types of cancers. Here we examine the effect of IL-12 treatment in preventing the colorectal cancer liver metastasis in a mice model. At different doses, we found that IL-12 treatment decreased the formation of liver metastasis sites and the percentage of metastasis volume in the liver. Additionally, this treatment leads to improved survival function of mice after tumor cell transplantation. We believe that IL-12 based therapy provided a novel treatment to colorectal cancer patients suffering from liver metastasis.

Relationship between vascular endothelial growth factors and liver diseases

Vascular endothelial growth factors play an important role in the processes of cell differentiation and maturation. As a kind of multi-functional factor, they are closely related to the occurrence and progression of liver diseases. They can not only promote postoperative liver regeneration but also repress the propagation of chronic hepatitis B and liver cirrhosis. In addition, they have a role in cancer diagnosis and treatment and graft rejection in liver transplantation. In this paper, we will give a brief introduction of vascular growth factors and their role in liver regeneration, cirrhosis, liver cancer and liver transplantation.