Biomarkers in precision therapy in colorectal cancer

Prognostic Biomarkers of Cell Proliferation in Colorectal Cancer (CRC): From Immunohistochemistry to Molecular Biology Techniques

Colorectal cancer (CRC) is one of the most common and severe malignancies worldwide. Recent advances in diagnostic methods allow for more accurate identification and detection of several molecular biomarkers associated with this cancer. Nonetheless, non-invasive and effective prognostic and predictive testing in CRC patients remains challenging. Classical prognostic genetic markers comprise mutations in several genes (e.g., APC, KRAS/BRAF, TGF-β, and TP53). Furthermore, CIN and MSI serve as chromosomal markers, while epigenetic markers include CIMP and many other candidates such as SERP, p14, p16, LINE-1, and RASSF1A. The number of proliferation-related long non-coding RNAs (e.g., SNHG1, SNHG6, MALAT-1, CRNDE) and microRNAs (e.g., miR-20a, miR-21, miR-143, miR-145, miR-181a/b) that could serve as potential CRC markers has also steadily increased in recent years. Among the immunohistochemical (IHC) proliferative markers, the prognostic value regarding the patients' overall survival (OS) or disease-free survival (DFS) has been confirmed for thymidylate synthase (TS), cyclin B1, cyclin D1, proliferating cell nuclear antigen (PCNA), and Ki-67. In most cases, the overexpression of these markers in tissues was related to worse OS and DFS. However, slowly proliferating cells should also be considered in CRC therapy (especially radiotherapy) as they could represent a reservoir from which cells are recruited to replenish the rapidly proliferating population in response to cell-damaging factors. Considering the above, the aim of this article is to review the most common proliferative markers assessed using various methods including IHC and selected molecular biology techniques (e.g., qRT-PCR, in situ hybridization, RNA/DNA sequencing, next-generation sequencing) as prognostic and predictive markers in CRC.

eIF3f Mediates SGOC Pathway Reprogramming by Enhancing Deubiquitinating Activity in Colorectal Cancer

Numerous studies have demonstrated that individual proteins can moonlight. Eukaryotic Initiation translation factor 3, f subunit (eIF3f) is involved in critical biological functions; however, its role independent of protein translation in regulating colorectal cancer (CRC) is not characterized. Here, it is demonstrated that eIF3f is upregulated in CRC tumor tissues and that both Wnt and EGF signaling pathways are participating in eIF3f's oncogenic impact on targeting phosphoglycerate dehydrogenase (PHGDH) during CRC development. Mechanistically, EGF blocks FBXW7β-mediated PHGDH ubiquitination through GSK3β deactivation, and eIF3f antagonizes FBXW7β-mediated PHGDH ubiquitination through its deubiquitinating activity. Additionally, Wnt signals transcriptionally activate the expression of eIF3f, which also exerts its deubiquitinating activity toward MYC, thereby increasing MYC-mediated PHGDH transcription. Thereby, both impacts allow eIF3f to elevate the expression of PHGDH, enhancing Serine-Glycine-One-Carbon (SGOC) signaling pathway to facilitate CRC development. In summary, the study uncovers the intrinsic role and underlying molecular mechanism of eIF3f in SGOC signaling, providing novel insight into the strategies to target eIF3f-PHGDH axis in CRC.

Therapeutic potential of Clostridium butyricum anticancer effects in colorectal cancer

Probiotic roles of Clostridium butyricum (C.B) are involved in regulating disease and cancers, yet the mechanistic basis for these regulatory roles remains largely unknown. Here, we demonstrate that C.B reprograms the proliferation, migration, stemness, and tumor growth in CRC by regulating pivotal signal molecules including MYC. Destabilization of MYC by C.B supplementation suppresses cancer cell proliferation/metastasis, sensitizes 5-FU treatment, and boosts responsiveness of anti-PD1 therapy. MYC is a transcriptional regulator of Thymidylate synthase (TYMS), a key target of the 5-FU. Also MYC is known to impact on PD-1 expression. Mechanistically, C.B treatment of CRC cells results in MYC degradation by enhancing proteasome-mediated ubiquitination, thereby mitigating MYC-mediated 5-FU resistance and boosting anti-PD1 immunotherapeutic efficacy. Together, our findings uncover previously unappreciated links between C.B and CRC cell signaling, providing insight into the tumorigenesis modulating mechanisms of C.B in boosting chemo/immune therapies.

Roles of anoikis in colorectal cancer therapy and the assessment of anoikis-regulatory molecules as therapeutic targets

Colorectal cancer (CRC) is a deadly malignancy and therapeutic approaches for CRC are evolving every day. Anoikis is a key mechanism for programmed cell death of cancer cells that undergo anchorage-independent growth at a different matrix than the one which is expected. Yet, anoikis is a less studied mechanism of cell death in comparison to other mechanisms such as apoptosis. Relating to this, resistance to anoikis among cancer cells remains critical for improved metastasis and survival in a new environment evading anoikis. Since CRC cells have the ability to metastasize from proximal sites to secondary organs such as liver and promote cancer in those distant sites, a clear knowledge of the mechanisms essential for anchorage-independent growth and subsequent metastasis is necessary to counteract CRC progression and spread. Therefore, the identification of novel drug candidates and studying the roles of anoikis in assisting CRC therapy using such drugs can prevent anchorage-independent cancer cell growth. Additionally, the identification of novel biomarkers or therapeutic targets seems essential for implementing superior therapy, impeding relapse among malignant cells and improving the survival rate of clinical patients. As there are no reviews published on this topic till date, anoikis as a mechanism of cell death and its therapeutic roles in CRC are discussed in this review. In addition, several molecules were identified as therapeutic targets for CRC.

Advances in biomaterials for the treatment of retinoblastoma

Retinoblastoma is the most common primary intraocular malignancy in children. Although traditional chemotherapy has shown some success in retinoblastoma management, there are several shortcomings to this approach, including inadequate pharmacokinetic parameters, multidrug resistance, low therapeutic efficiency, nonspecific targeting, and the need for adjuvant therapy, among others. The revolutionary developments in biomaterials for drug delivery have enabled breakthroughs in cancer management. Today, biomaterials are playing a crucial role in developing more efficacious retinoblastoma treatments. The key goal in the evolution of drug delivery biomaterials for retinoblastoma therapy is to resolve delivery-associated obstacles and lower nonlocal exposure while ameliorating certain adverse effects. In this review, we will first delve into the historical perspective of retinoblastoma with a focus on the classical treatments currently used in clinics to enhance patients' quality of life and survival rate. As we move along, we will discuss biomaterials for drug delivery applications. Various aspects of biomaterials for drug delivery will be dissected, including their features and recent advances. In accordance with the current advances in biomaterials, we will deliver a synopsis on the novel chemotherapeutic drug delivery strategies and evaluate these approaches to gain new insights into retinoblastoma treatment.

Somatic mutations in colorectal cancer: regional experience

Introduction. Colorectal cancer is one of the most common malignant neoplasms in economically developed countries, ranking 3rd and 2nd in the structure of morbidity and mortality, respectively. Current knowledge about the molecular features of colorectal cancer is necessary to implement the principle of personalized therapy. Aim. To study regional features of tumor genomic landscape in colorectal cancer. Materials and methods. The retrospective study from 2019 to 2022 included 153 patients with stage IIV colorectal cancer aged 32 to 80 years, with a median of 63.8 years. DNA samples extracted from paraffin blocks of tumor tissue were analyzed using a real-time polymerase chain reaction. The study patients included 43.8% of males and 56.2% of females. Results. Somatic mutations were detected in 48.4% of patients. The maximum number of mutations was detected in the KRAS gene 60 (81%). The mutation rate was significantly higher in females versus males. KRAS mutations predominate in the colon compared to the rectum, accounting for 66.7 and 33.3%, respectively. In tumors of the right colon, these mutations were detected in 18.3% of cases, and in the left colon, 48.4%. NRAS mutations were found in 9.5% of cases, mainly in tumors of the left colon. BRAF mutations were diagnosed in 6 patients, 5 of them were women, and the tumors were localized in the right colon. The highest rate of KRAS mutations was observed in codons 12 and 13, accounting for 86.7% of cases. The G12V mutation occurred in the majority of patients (25%), followed by G12D (20%) and G12A (16.6%). Conclusion. Somatic mutations in RAS and BRAF genes in colorectal cancer were detected in 48.4% of patients in the Tambov region. Among them, there is a predominance of KRAS mutations 81% in females. KRAS oncogenic mutations are predictors of treatment response and prognosis.

Microsatellite instability and chemosensitivity in solid tumours

The use of biomarkers that influence a targeted choice in cancer treatments is the future of medical oncology. Within this scenario, in recent years, an important role has been played by knowledge of microsatellite instability (MSI), a molecular fingerprint that identifies defects in the mismatch repair system. This knowledge has changed clinical practice in the adjuvant setting of colon cancer, and its role in the neoadjuvant setting in gastric tumours is becoming increasingly interesting, as well as in endometrial cancers in both early and advanced diseases. Furthermore, it has undoubtedly conditioned the first lines of treatment in the metastatic setting in different types of cancers. The incidence of MSI is different in different cancer types, as well as in early cancers versus metastatic disease. Knowing the incidence of MSI in the various histologies can provide insight into the potential use of this biomarker considering its prognostic value, especially in the early stages, and its predictive role with respect to treatment response. In particular, MSI can guide the choice of chemotherapy treatments in the adjuvant setting of colon and perioperative setting in gastric tumours, which could lead to immunotherapy treatments in these patients in both the early stages of the disease and the metastatic setting where the response to immunotherapy drugs in diseases with MSI is now well established. In this review, we focus on colon, gastric and endometrial cancers, and we briefly discuss other cancer types where MSI could have a potential role in oncological treatment decisions.

Associations of Complete Blood Count Parameters with Disease-Free Survival in Right- and Left-Sided Colorectal Cancer Patients

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. Some complete blood count (CBC) parameters are found to be associated with CRC prognosis. In this study, ninety-seven pretreated CRC patients were included, and the patients were divided into two groups: left-sided and right-sided, depending on the anatomical location of the tumor. Based on clinicopathologic features including tumor budding, disease stages, and tumor anatomical location, levels of CBC parameters were compared, and disease-free survivals (DFS) were determined. There were differences between patients with different tumor budding scores for only three parameters, including red cell distribution width (RDW), numbers of platelets, and mean platelet volume (MPV). Furthermore, numbers of WBCs, monocytes, and MPV in CRC patients with early disease stages were higher than those with advanced stages. However, levels of eosinophil in CRC patients with advanced stages were higher than those with early stages. Depending on the tumor anatomical location, we observed that numbers of red blood cells (RBCs), hemoglobin (Hgb), and hematocrit (Hct) in CRC patients with left-sided tumors were higher than those with right-sided tumors. We found that low levels of MPV were associated with shorter DFS. However, high levels of eosinophils were associated with shorter DFS in all CRC patients. When patients were divided based on the tumor anatomical location, higher levels of MPV, MCHC, and Hgb were associated with better DFS in the left-sided but not right-sided CRC patients. However, left-sided, but not right-sided, CRC patients with high levels of eosinophil and RDW had shorter DFS. Furthermore, right-sided, but not left-sided, CRC patients with high levels of platelets tended to have a shorter DFS. Our data show that MPV and eosinophils could serve as potential prognostic biomarkers in pre-treatment CRC patients, regardless of the tumor anatomical location. Additionally, lower levels of MPV, MCHC, and Hgb, and high levels of eosinophils and RDW could be negative predictive biomarkers in left-sided CRC patients.

The expression of ADAMTS14 is regulated by promoter DNA methylation and is associated with poor prognosis in colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant tumors of digestive system, and its main cause of death is tumor metastasis. The occurrence of CRC is a polygenic and multi-step complex process involving genetic and epigenetic alterations. It has been demonstrated that ADAMTS14 (A disintegrin and metalloproteinase with thrombospondin motifs 14) was hypermethylated in esophageal cancer using whole-genome methylation microarray in our previous report. The present study revealed that ADAMTS14 was highly methylated accompanied with low expression in CRC. In addition, demethylation agent 5-Aza-dC could demethylate ADAMTS14 promoter region and reactivate ADAMTS14 expression effectively in vitro. Therefore, promoter hypermethylation was probably contributed to ADAMTS14 epigenetic silencing in CRC. Furthermore, ADAMTS14 protein expression was higher at invasive tumor front than at the tumor center or other areas of tumor. Kaplan-meier survival analysis indicated that the high ADAMTS14 expression was correlated with poor prognosis in CRC patients, suggesting the possibility that ADAMTS14 is a promising indicator in the evaluation of CRC prognosis.

Methylation status of ADAM12 promoter are associated with its expression levels in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a kind of malignant tumor of digestive system severely affecting human health. The occurrence of CRC is a polygenic and multi-step complex process involving genetic and epigenetic alterations. ADAM12 (a disintegrin and metalloproteases 12), is a gene that was commonly hypermethylated in esophageal cancer using whole-genome methylation microarray in our previous study.

METHODS

We detected the methylation frequencies of the CpG island in ADAM12 promoter using bisulfite-pyrosequencing in CRC cell lines and tissue samples. The expression of ADAM12 was detected by quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC). A systematic and comprehensive analysis of relationship of DNA hypermethylation and ADAM12 expression in CRC was performed in our samples and TCGA database.

RESULTS

The expression of ADAM12 in hypermethylated cell lines was significantly lower than that in hypomethylated cell lines, and demethylation agent 5-Aza-dC could demethylate ADAM12 promoter region and reactivate ADAM12 expression effectively. In 74 pairs of colorectal cancer and normal tissues, bisulfite-pyrosequencing results showed significantly hypermethylation of ADAM12 in CRC compared with adjacent normal mucosa, accompanied with lower expression of ADAM12 in CRC tissues compared to that of the normal tissues. In addition, there was a statistically significant negative correlation between ADAM12 protein expression and methylation levels (rho =-0.28, p = 0.015).

CONCLUSION

Promoter hypermethylation was probably a mechanism of ADAM12 epigenetic silencing in CRC.

Treating Colorectal Cancer with Immunotherapy: Implications for Single versus Combination Therapy

PURPOSE OF REVIEW

Colorectal cancer (CRC) is the second leading cause of cancer-associated deaths in the United States, with most metastatic cases subsequently turning refractory to standard chemotherapy. One of the promising current interventions is immunotherapy that relies on harnessing the body's immune mechanisms to kill the cancer cells. The aim of this review is to highlight the implications of single versus combination immunotherapy and identify the molecular features and mutations that enhance or deter responsiveness.

RECENT FINDINGS

Based on current findings, responsiveness is associated with deficiency of mismatch repair (dMMR) genes or presence of microsatellite instability (MSI-high), with high immunoscore and tumor-mutational burden contributing to better efficacy while BRAF mutation conferring no significant effect. Combination immunotherapy demonstrates better efficacy in treating MSI-high CRC compared to single agent immunotherapy or chemotherapy.

SUMMARY

Given improved responsiveness and overall survival, there is potential for immunotherapy to change the standard of care for metastatic CRC. Furthermore, stratifying the patients by their molecular features and mutation status is critical for establishing care.

Biomarkers in Colorectal Cancer: Current Research and Future Prospects

Colorectal cancer (CRC) is a leading cause of death worldwide, despite progress made in detection and management through surgery, chemotherapy, radiotherapy, and immunotherapy. Novel therapeutic agents have improved survival in both the adjuvant and advanced disease settings, albeit with an increased risk of toxicity and cost. However, metastatic disease continues to have a poor long-term prognosis and significant challenges remain due to late stage diagnosis and treatment failure. Biomarkers are a key tool in early detection, prognostication, survival, and predicting treatment response. The past three decades have seen advances in genomics and molecular pathology of cancer biomarkers, allowing for greater individualization of therapy with a positive impact on survival outcomes. Clinically useful predictive biomarkers aid clinical decision making, such as the presence of KRAS gene mutations predicting benefit from epidermal growth factor receptor (EGFR) inhibiting antibodies. However, few biomarkers have been translated into clinical practice highlighting the need for further investigation. We review a range of protein, DNA and RNA-based biomarkers under investigation for diagnostic, predictive, and prognostic properties for CRC. In particular, long non-coding RNAs (lncRNA), have been investigated as biomarkers in a range of cancers including colorectal cancer. Specifically, we evaluate the potential role of lncRNA plasmacytoma variant translocation 1 (PVT1), an oncogene, as a diagnostic, prognostic, and therapeutic biomarker in colorectal cancer.

TRP Channels in Digestive Tract Cancers

Cancers of the digestive tract are among the most prevalent types of cancer. These types of cancers are often diagnosed at a late stage, which results in a poor prognosis. Currently, many biomedical studies focus on the role of ion channels, in particular transient receptor potential (TRP) channels, in cancer pathophysiology. TRP channels show mostly non-selective permeability to monovalent and divalent cations. TRP channels are often dysregulated in digestive tract cancers, which can result in alterations of cancer hallmark functions, such as enhanced proliferation, migration, invasion and the inability to induce apoptosis. Therefore, TRP channels could serve as potential diagnostic biomarkers. Moreover, TRP channels are mostly expressed on the cell surface and ion channel targeting drugs do not need to enter the cell, making them attractive candidate drug targets. In this review, we summarize the current knowledge about TRP channels in connection to digestive tract cancers (oral cancer, esophageal cancer, liver cancer, pancreatic cancer, gastric cancer and colorectal cancer) and give an outlook on the potential of TRP channels as cancer biomarkers or therapeutic targets.

LncRNA LUCRC Regulates Colorectal Cancer Cell Growth and Tumorigenesis by Targeting Endoplasmic Reticulum Stress Response

Colorectal cancer (CRC) is the second most common cause of cancer-related death worldwide, and is well known for its strong invasiveness, rapid recurrence, and poor prognosis. Long non-coding RNAs (lncRNAs) have been shown to be involved in the development of various types of cancers, including colorectal cancer. Here, through transcriptomic analysis and functional screening, we reported that lncRNA LUCRC (LncRNA Upregulated in Colorectal Cancer) is highly expressed in colorectal tumor samples and is required for colorectal cancer cell proliferation, migration, and invasion in cultured cells and tumorigenesis in xenografts. LUCRC was found to regulate target gene expression of unfolded protein response (UPR) in endoplasmic reticulum (ER), such as BIP. The clinical significance of LUCRC is underscored by the specific presence of LUCRC in blood plasma of patients with colorectal cancers. These findings revealed a critical regulator of colorectal cancer development, which might serve as a therapeutic target in colorectal cancer.

A Hallmark-Based Six-Gene Expression Signature to Assess Colorectal Cancer and Its Recurrence Risk

Purpose: As part of the effort to establish a general profile for solid tumors, the aim of this study was to develop a real-time polymerase chain reaction (RT-PCR)-based assay to assess colorectal cancer (CRC) and its recurrence risk utilizing the limited amounts of tissues available from biopsies through colonoscopy. Materials and Methods: Six candidate genes, reflecting the hallmarks of cancer cells, were identified by analyzing the gene expression profiles of primary invasive tumors in the public database. The expression of these genes in CRC and noncancerous colon tissues was quantified by RT-quantitative PCR. Classifiers were then generated to distinguish the tumors from the normal colon tissues, and to assess the risk of CRC recurrence based on the disease-free survival time, overall survival time, and metastatic status of the patients. Results: The expression profile of a five-gene panel was utilized to build a model that is capable of distinguishing CRC cancer tissues from noncancerous colorectal tissues (p < 0.0001). A classifier based on the expression signature of four genes, three of which were included in the five-gene panel, was then developed for assessing the tumor recurrence risk. This classifier could correctly identify those with a poor likelihood of survival (high risk of recurrence) >80% of time. There was a significant difference in disease-free survival time between patients in the low recurrence group and those in the high-risk group. Conclusion: The expression signatures of the six genes that reflect the genetic hallmarks of cancer cells could serve as a biomarker for identifying CRC and assessing the risk of recurrence with high sensitivity and specificity.

Heat shock protein beta 3 (HSPB3) is an unfavorable molecular biomarker in colorectal adenocarcinoma

Small heat shock proteins (sHSPs) participate in numerous cellular functions including cell signaling, differentiation, and apoptosis. Deregulation of the physiological expression level of sHSPs has been associated with several malignancies. Heat shock protein beta 3 (HSPB3) is the third member of the sHSP family in human and is mainly expressed in skeletal and smooth muscles. In this study, we investigated the potential prognostic significance of HSPB3 expression in colorectal adenocarcinoma, the most frequent type of colorectal cancer. For this purpose, we isolated total RNA from 188 colorectal adenocarcinoma specimens and 68 paired noncancerous ones. After reverse transcription of 2 μg total RNA, we quantified HSPB3 levels by using an in-house-developed real-time quantitative polymerase chain reaction method, based on the SYBR Green chemistry. Comparison of HSPB3 levels among 68 pairs of colorectal tumors and their adjacent noncancerous mucosae uncovered the downregulation of HSPB3 expression in the majority of malignant colorectal tumors. More importantly, high HSPB3 expression is associated with poor relapse-free survival (RFS) and overall survival (OS) of patients with colorectal adenocarcinoma. Multivariable Cox regression analysis revealed that HSPB3 overexpression could serve as an adverse prognostic biomarker in colorectal adenocarcinoma, independent of tumor location, histological grade, and TNM stage. Patients' stratification according to tumor location, histological grade, and TNM stage revealed that high HSPB3 messenger RNA expression retains its unfavorable prognostic potential regarding OS, in particular groups of patients with substantially different prognosis. In conclusion, high HSPB3 expression is associated with poor RFS and OS of patients with colorectal adenocarcioma, independently of clinicopathological prognosticators.

A novel lncRNA NR4A1AS up-regulates orphan nuclear receptor NR4A1 expression by blocking UPF1-mediated mRNA destabilization in colorectal cancer

Long non-coding RNAs (lncRNAs) play important roles in tumorigenesis and cancer progression. The orphan nuclear receptor subfamily 4 group A member 1 (NR4A1) acts as an oncogene, and is involved in colorectal cancer (CRC) development. However, the mechanism through which lncRNA regulates NR4A1 expression remains unknown. We aimed to identify lncRNAs that regulate NR4A1 and assess their underlying mechanisms in CRC. We first identified an antisense lncRNA of NR4A1 that was up-regulated in CRC tissues and cells with rapid amplification of cDNA ends (RACE), and designated it as NR4A1AS. Spearman correlation analysis showed that NR4A1AS was positively correlated with NR4A1 mRNA levels in 37 CRC tissues. Mechanistically, NR4A1AS stabilized NR4A1 mRNA by forming RNA-RNA complexes via partial base-pairing and up-regulated NR4A1 expression in CRC cells. RNA immunoprecipitation (RIP) assays revealed that knockdown of NR4A1AS expression by siRNA enhanced up-frameshift 1 (UPF1) recruitment to NR4A1 mRNA, thereby decreasing NR4A1 mRNA stability. Moreover, depletion of NR4A1AS was found to mimic the effect of NR4A1 knockdown, specifically by suppressing cell proliferation, migration and invasion, and inducing apoptosis and cell cycle arrest. Accordingly, restoring NR4A1 expression ameliorated the effects of NR4A1AS knockdown on tumor growth and metastasis of CRC cells in vitro and in vivo Thus, we conclude that NR4A1AS up-regulates NR4A1 expression by forming RNA-RNA complexes and blocking UPF1-mediated mRNA destabilization, and it functions in tumor growth and metastasis of CRC cells at least partly through regulating NR4A1, suggesting that NR4A1AS might be as a potential target for RNA-based anti-CRC drug studies.

Mechanism of Apoptosis Induced by Curcumin in Colorectal Cancer

Colorectal cancer (CRC) is among the top three cancer with higher incident and mortality rate worldwide. It is estimated that about over than 1.1 million of death and 2.2 million new cases by the year 2030. The current treatment modalities with the usage of chemo drugs such as FOLFOX and FOLFIRI, surgery and radiotherapy, which are usually accompanied with major side effects, are rarely cured along with poor survival rate and at higher recurrence outcome. This trigger the needs of exploring new natural compounds with anti-cancer properties which possess fewer side effects. Curcumin, a common spice used in ancient medicine was found to induce apoptosis by targeting various molecules and signaling pathways involved in CRC. Disruption of the homeostatic balance between cell proliferation and apoptosis could be one of the promoting factors in colorectal cancer progression. In this review, we describe the current knowledge of apoptosis regulation by curcumin in CRC with regard to molecular targets and associated signaling pathways.

Plasma cytokine levels and the presence of colorectal cancer

Background/Aims

Cancer-related activation of cytokine networks are central aspects of tumor development. The goal of the study was to examine the possibility of plasma cytokines for the screening of colorectal cancer (CRC).

Methods

We carried out a multicenter, hospital-based case-control study in 66 adult Japanese patients with CRC and 87 healthy adult Japanese. A multiplex bead array immunoassay was used to examine 27 different plasma cytokines. Their association with the presence of CRC was evaluated by logistic regression analysis after adjusting for potential confounding factors.

Results

Thirteen plasma cytokines were notably associated with the presence of CRC (p< 0.05). Receiver operating characteristic analysis revealed that the combinatorial assessment of some of these plasma cytokines showed “good” capability for discriminating between CRC patients and control subjects (area under the curve (AUC): 0.819 for the combination of IL-9, Eotaxin, G-CSF, and TNF-α; 0.832 for the combination of IL-4, IL-8, Eotaxin, IP-10, and TNF-α). Individual cytokine assessments presented lower AUCs (0.657–0.755) than the combinatorial cytokine assessments.

Conclusions

The levels of several plasma cytokines varied significantly between CRC patients and control subjects, suggesting the possibility of differentially expressed plasma cytokines as potential biomarkers for detecting the presence of CRC. Our results should be validated in other populations.

Insights into Pathogenic Interactions Among Environment, Host, and Tumor at the Crossroads of Molecular Pathology and Epidemiology

Evidence indicates that diet, nutrition, lifestyle, the environment, the microbiome, and other exogenous factors have pathogenic roles and also influence the genome, epigenome, transcriptome, proteome, and metabolome of tumor and nonneoplastic cells, including immune cells. With the need for big-data research, pathology must transform to integrate data science fields, including epidemiology, biostatistics, and bioinformatics. The research framework of molecular pathological epidemiology (MPE) demonstrates the strengths of such an interdisciplinary integration, having been used to study breast, lung, prostate, and colorectal cancers. The MPE research paradigm not only can provide novel insights into interactions among environment, tumor, and host but also opens new research frontiers. New developments-such as computational digital pathology, systems biology, artificial intelligence, and in vivo pathology technologies-will further transform pathology and MPE. Although it is necessary to address the rarity of transdisciplinary education and training programs, MPE provides an exemplary model of integrative scientific approaches and contributes to advancements in precision medicine, therapy, and prevention.

Are Colon and Rectal Cancer Two Different Tumor Entities? A Proposal to Abandon the Term Colorectal Cancer

Colon cancer (CC) and rectal cancer (RC) are synonymously called colorectal cancer (CRC). Based on our experience in basic and clinical research as well as routine work in the field, the term CRC should be abandoned. We analyzed the available data from the literature and results from our multicenter Research Group Oncology of Gastrointestinal Tumors termed FOGT to confirm or reject this hypothesis. Anatomically, the risk of developing RC is four times higher than CC, while physical activity helps to prevent CC but not RC. Obvious differences exist in molecular carcinogenesis, pathology, surgical topography and procedures, and multimodal treatment. Therefore, we conclude that CC is not the same as RC. The term "CRC" should no longer be used as a single entity in basic and clinical research as well as other areas of classification.

The long non-coding RNA CYTOR drives colorectal cancer progression by interacting with NCL and Sam68

BACKGROUND

Long non-coding RNAs (lncRNAs) function as key molecules in cancer progression. The lncRNA CYTOR plays oncogenic roles in multiple types of cancer, yet the detailed molecular mechanisms of those roles remain unknown. The aim of this study was to investigate the clinical significance, biological function and interacting partners of CYTOR in colorectal cancer (CRC).

METHODS

A systematic and comprehensive analysis of CYTOR expression was performed in 138 CRC samples and in the TCGA and GEO databases. Biological function was investigated through knockdown and overexpression of CYTOR in vitro and in vivo. In addition, its protein binding partner was identified and validated using ChIRP-MS and RNA immunoprecipitation assays. Their key interaction sites on CYTOR were verified by CRISPR/Cas9 and a series of mutant constructs. Furthermore, the downstream targets of CYTOR were confirmed via immunoblotting and luciferase reporter assays.

RESULTS

CYTOR was significantly up-regulated in CRC samples and associated with poor prognosis, promoting proliferation and metastasis in vitro and in vivo. NCL and Sam68 could recognize their specific motifs and directly bind to EXON1 of CYTOR. Moreover, EXON1 was the key functional site mediating the interaction of CYTOR with NCL and Sam68. NCL and Sam68 functioned as oncogenes to promote CRC progression. Furthermore, we confirmed that the heterotrimeric complex of CYTOR, NCL and Sam68 activated the NF-κB pathway and EMT to contribute to CRC progression.

CONCLUSION

CYTOR plays important roles in CRC progression by interacting with NCL and Sam68 and may serve as a prognostic biomarker and/or an effective target for CRC therapies.

The molecular characteristics of colorectal cancer: Implications for diagnosis and therapy

Colorectal cancer (CRC) results from the progressive accumulation of multiple genetic and epigenetic aberrations within cells. The progression from colorectal adenoma to carcinoma is caused by three major pathways: Microsatellite instability, chromosomal instability and CpG island methylator phenotype. A growing body of scientific evidences suggests that CRC is a heterogeneous disease, and genetic characteristics of the tumors determine their prognostic outcome and response to targeted therapies. Early diagnosis and effective targeted therapies based on a current knowledge of the molecular characteristics of CRC are essential to the successful treatment of CRC. Therefore, the present review summarized the current understanding of the molecular characteristics of CRC, and discussed its implications for diagnosis and targeted therapy.

The impacts of pretreatment circulating eosinophils and basophils on prognosis of stage Ⅰ-Ⅲ colorectal cancer

AIM

The effects of circulating eosinophils and basophils on cancer survival are unclear. Here, we aimed to explore the impacts of eosinophils and basophils on prognosis of stage I-III colorectal cancer (CRC) patients.

METHODS

From February 2003 to March 2013, 569 stage I-III CRC patients were enrolled in this retrospective study. The associations between pretreatment circulating eosinophils, basophils and CRC overall survival (OS), disease-free survival (DFS) were investigated. Moreover, the prognostic value of combined eosinophils/basophils and neutrophil to lymphocyte ratio (NLR)/platelet to lymphocyte ratio (PLR) was investigated.

RESULTS

Kaplan-Meier methods showed the associations of eosinophils < 0.095 × 10⁹ /L and shorter OS (P < 0.0001), eosinophils < 0.055 × 10⁹ /L and shorter DFS (P < 0.0001), basophils < 0.015 × 10⁹ /L and shorter OS (P = 0.001), basophils < 0.015 × 10⁹ /L and shorter DFS (P = 0.005). Cox regression model showed that eosinophils < 0.095 × 10⁹ /L (hazard ratio [HR], 1.723; 95% confidence intervals [CI] = 1.177-2.523) and basophils < 0.015 × 10⁹ /L (HR, 1.714; 95% CI = 1.152-2.548) were independent prognostic factors for OS, and eosinophils < 0.055 × 10⁹ /L (HR, 2.309; 95% CI = 1.587-3.361) and basophils < 0.015 × 10⁹ /L (HR, 1.397; 95% CI = 1.003-1.945) were independent prognostic factors for DFS, respectively. The combined eosinophil-PLR (HR, 2.611; 95% CI = 1.328-5.130) and basophil-PLR (HR, 2.520; 95% CI = 1.240-5.123) were the independent prognostic factors for OS. The combined eosinophil-NLR (HR, 2.770; 95% CI = 1.528-5.019) and eosinophil-PLR (HR, 4.788; 95% CI = 2.458-9.329) were the independent prognostic factors for DFS.

CONCLUSION

Pretreatment circulating eosinophils < 0.095 × 10⁹ /L/0.055 × 10⁹ /L and circulating basophils < 0.015 × 10⁹ /L have significant impacts on prognosis of stage I-III CRC patients.

Dysbiosis of gut microbiota in promoting the development of colorectal cancer

Gastrointestinal microbiome, containing at least 100 trillion bacteria, resides in the mucosal surface of human intestine. Recent studies show that perturbations in the microbiota may influence physiology and link to a number of diseases, including colon tumorigenesis. Colorectal cancer (CRC), the third most common cancer, is the disease resulting from multi-genes and multi-factors, but the mechanistic details between gut microenvironment and CRC remain poorly characterized. Thanks to new technologies such as metagenome sequencing, progress in large-scale analysis of the genetic and metabolic profile of gut microbial has been possible, which has facilitated studies about microbiota composition, taxonomic alterations and host interactions. Different bacterial species and their metabolites play critical roles in the development of CRC. Also, microbiota is important in the inflammatory response and immune processes deregulation during the development and progression of CRC. This review summarizes current studies regarding the association between gastrointestinal microbiota and the development of CRC, which provides insights into the therapeutic strategy of CRC.

Novel evidence for a PIWI-interacting RNA (piRNA) as an oncogenic mediator of disease progression, and a potential prognostic biomarker in colorectal cancer

Background

Emerging evidence suggests that PIWI-interacting RNAs (piRNAs) may be important epigenetic regulators of gene expression in human cancers; however, their functional and clinical significance in colorectal cancer (CRC) remains unknown.

Methods

We performed piRNA expression profiling in paired cancer and normal tissues through small RNA-sequencing. The clinical significance of candidate piRNAs was investigated, and independently validated in 771 CRC patients from three independent cohorts. The biological function of piRNAs was characterized in cell lines, followed by identification and validation of downstream target genes in CRC tissues.

Results

We identified piR-1245 as a novel and frequently overexpressed noncoding RNA in CRC, and its expression significantly correlated with advanced and metastatic disease. Patients with high piR-1245 expression experienced significantly shorter overall survival, and multivariate analysis identified its expression to serve as an independent prognostic biomarker in CRC. Functionally, piR-1245 acts as an oncogene and promotes tumor progression, and gene expression profiling results identified a panel of downstream target-genes involved in regulating cell survival pathway. Based upon piRNA:mRNA sequence complementarity, we identified a panel of tumor suppressor genes (ATF3, BTG1, DUSP1, FAS,NFKBIA, UPP1, SESN2, TP53INP1 and MDX1) as direct targets of piR-1245, and successfully validated an inverse correlation between their expression and piR-1245 in CRC.

Conclusions

We for the first time have identified the role for a PIWI-interacting noncoding RNA, piR-1245, as a novel oncogene and a potential prognostic biomarker in colorectal cancer.

Electronic supplementary material

The online version of this article (10.1186/s12943-018-0767-3) contains supplementary material, which is available to authorized users.

Integration of pharmacology, molecular pathology, and population data science to support precision gastrointestinal oncology

Precision medicine has a goal of customizing disease prevention and treatment strategies. Under the precision medicine paradigm, each patient has unique pathologic processes resulting from cellular genomic, epigenomic, proteomic, and metabolomic alterations, which are influenced by pharmacological, environmental, microbial, dietary, and lifestyle factors. Hence, to realize the promise of precision medicine, multi-level research methods that can comprehensively analyze many of these variables are needed. In order to address this gap, the integrative field of molecular pathology and population data science (i.e., molecular pathological epidemiology) has been developed to enable such multi-level analyses, especially in gastrointestinal cancer research. Further integration of pharmacology can improve our understanding of drug effects, and inform decision-making of drug use at both the individual and population levels. Such integrative research demonstrated potential benefits of aspirin in colorectal carcinoma with PIK3CA mutations, providing the basis for new clinical trials. Evidence also suggests that HPGD (15-PDGH) expression levels in normal colon and the germline rs6983267 polymorphism that relates to tumor CTNNB1 (β-catenin)/WNT signaling status may predict the efficacy of aspirin for cancer chemoprevention. As immune checkpoint blockade targeting the CD274 (PD-L1)/PDCD1 (PD-1) pathway for microsatellite instability-high (or mismatch repair-deficient) metastatic gastrointestinal or other tumors has become standard of care, potential modifying effects of dietary, lifestyle, microbial, and environmental factors on immunotherapy need to be studied to further optimize treatment strategies. With its broad applicability, our integrative approach can provide insights into the interactive role of medications, exposures, and molecular pathology, and guide the development of precision medicine.

Decreased expression of RASSF10 correlates with poor prognosis in patients with colorectal cancer

Ras association domain protein 10 (RASSF10) was reported to act as a prognostic indicator in various types of cancer and it was proved to be tumor suppressor gene in colorectal cancer (CRC). The purpose of this study was to evaluate the prognostic significance of RASSF10 in CRC.Quantitative real-time polymerase chain reaction was used to detect the messenger RNA (mRNA) expression while enzyme-linked immunosorbent assay was taken to measure the protein expression of RASSF10 in tumor tissues and adjacent normal tissues from 102 patients with CRC. The relationship between RASSF10 expression level and clinical characteristics of CRC patients was analyzed by chi-squared test. In addition, the association between overall survival of CRC patients and RASSF10 expression was estimated by Kaplan-Meier analysis. Cox regression analysis was used to evaluate the prognostic value of RASSF10.The expression level of RASSF10 in tumor tissues was significantly lower than that in the normal tissues both at mRNA and protein levels. Moreover, the expression level was correlated with lymph-node-metastasis and tumor-node-metastasis stage. Kaplan-Meier analysis suggested that patients with high expression level of RASSF10 had a longer overall survival than those with low level (log-rank test, P < .001). Besides, RASSF10 might be a potential biomarker in the prognosis of CRC according to cox regression analysis.The down regulated of RASSF10 is found in CRC and it may be an ideal prognostic marker.

Aspirin exerts high anti-cancer activity in PIK3CA-mutant colon cancer cells

Evidence suggests that nonsteroidal anti-inflammatory drug aspirin (acetylsalicylic acid) may improve patient survival in PIK3CA-mutant colorectal carcinoma, but not in PIK3CA-wild-type carcinoma. However, whether aspirin directly influences the viability of PIK3CA-mutant colon cancer cells is poorly understood. We conducted in vitro experiments to test our hypothesis that the anti-proliferative activity of aspirin might be stronger for PIK3CA-mutant colon cancer cells than for PIK3CA-wild-type colon cancer cells. We measured the anti-proliferative effect of aspirin at physiologic concentrations in seven PIK3CA-mutant and six PIK3CA-wild-type human colon cancer cell lines. After exposure to aspirin, the apoptotic index and cell cycle phase of colon cancer cells were assessed. In addition, the effect of aspirin was examined in parental SW48 cells and SW48 cell clones with individual knock-in PIK3CA mutations of either c.3140A>G (p.H1047R) or c.1633G>A (p.E545K). Aspirin induced greater dose-dependent loss of cell viability in PIK3CA-mutant cells than in PIK3CA-wild-type cells after treatment for 48 and 72 hours. Aspirin treatment also led to higher proportions of apoptotic cells and G0/G1 phase arrest in PIK3CA-mutant cells than in PIK3CA-wild-type cells. Aspirin treatment of isogenic SW48 cells carrying a PIK3CA mutation, either c.3140A>G (p.H1047R) or c.1633G>A (p. E545K), resulted in a more significant loss of cell viability compared to wild-type controls. Our findings indicate that aspirin causes cell cycle arrest, induces apoptosis, and leads to loss of cell viability more profoundly in PIK3CA-mutated colon cancer cells than in PIK3CA-wild-type colon cancer cells. These findings support the use of aspirin to treat patients with PIK3CA-mutant colon cancer.

Long non-coding RNAs in Colorectal Cancer: Progression and Future Directions

Identification of the colorectal adenoma-carcinoma sequence with its corresponding genetic and epigenetic alterations has significantly increased our knowledge of the etiopathogenesis of colorectal cancer (CRC). However, the molecular mechanisms of colorectal carcinogenesis and metastasis haven't been clearly elucidated. Long non-coding ribonucleic acids (lncRNAs) are key participants of gene regulations rather than “noises”. Accumulative studies have implicated that the aberrant expressions of lncRNAs are tightly corelated to CRC screening, diagnosis, prognosis and therapeutic outcomes. Our review focuses on recent findings on the involvement of lncRNAs in CRC oncogenesis and the lncRNA-based clinical implications in patients with CRC.

Proteins are potent biomarkers to detect colon cancer progression

Colon cancer is the most common type of cancer and major cause of death worldwide. The detection of colon cancer is difficult in early stages. However, the secretory proteins have been used as ideal biomarker for the detection of colon cancer progress in cancer patients. Serum/tissue protein expression could help general practitioners to identify colon cancer at earlier stages. By this way, we use the biomarkers to evaluate the anticancer drugs and their response to therapy in cancer models. Recently, the biomarker discovery is important in cancer biology and disease management. Also, many measurable specific molecular components have been studied in colon cancer therapeutics. The biomolecules are mainly DNA, RNA, metabolites, enzymes, mRNA, aptamers and proteins. Thus, in this review we demonstrate the important protein biomarker in colon cancer development and molecular identification of protein biomarker discovery.

Prediction of novel target genes and pathways involved in irinotecan-resistant colorectal cancer

Background

Acquired drug resistance to the chemotherapeutic drug irinotecan (the active metabolite of which is SN-38) is one of the significant obstacles in the treatment of advanced colorectal cancer (CRC). The molecular mechanism or targets mediating irinotecan resistance are still unclear. It is urgent to find the irinotecan response biomarkers to improve CRC patients’ therapy.

Methods

Genetic Omnibus Database GSE42387 which contained the gene expression profiles of parental and irinotecan-resistant HCT-116 cell lines was used. Differentially expressed genes (DEGs) between parental and irinotecan-resistant cells, protein-protein interactions (PPIs), gene ontologies (GOs) and pathway analysis were performed to identify the overall biological changes. The most common DEGs in the PPIs, GOs and pathways were identified and were validated clinically by their ability to predict overall survival and disease free survival. The gene-gene expression correlation and gene-resistance correlation was also evaluated in CRC patients using The Cancer Genomic Atlas data (TCGA).

Results

The 135 DEGs were identified of which 36 were upregulated and 99 were down regulated. After mapping the PPI networks, the GOs and the pathways, nine genes (GNAS, PRKACB, MECOM, PLA2G4C, BMP6, BDNF, DLG4, FGF2 and FGF9) were found to be commonly enriched. Signal transduction was the most significant GO and MAPK pathway was the most significant pathway. The five genes (FGF2, FGF9, PRKACB, MECOM and PLA2G4C) in the MAPK pathway were all contained in the signal transduction and the levels of those genes were upregulated. The FGF2, FGF9 and MECOM expression were highly associated with CRC patients’ survival rate but not PRKACB and PLA2G4C. In addition, FGF9 was also associated with irinotecan resistance and poor disease free survival. FGF2, FGF9 and PRKACB were positively correlated with each other while MECOM correlated positively with FGF9 and PLA2G4C, and correlated negatively with FGF2 and PRKACB after doing gene-gene expression correlation.

Conclusion

Targeting the MAPK signal transduction pathway through the targeting of the FGF2, FGF9, MECOM, PLA2G4C and PRKACB might increase tumor responsiveness to irinotecan treatment.

AQP9-induced cell cycle arrest is associated with RAS activation and improves chemotherapy treatment efficacy in colorectal cancer

Aquaporin-9 (AQP9) expression is associated with arsenic sensitivity in leukemia cells. However, the role of AQP9 in regulating tumor sensitivity to adjuvant chemotherapy in colorectal cancer (CRC) has not been elucidated. In this study, we demonstrated that AQP9 can serve as an independent predictive marker for adjuvant chemotherapy in CRC. Patients with high AQP9 expression had higher rate of disease-free survival (DFS) than those with low AQP9 expression. Upregulation of AQP9 was associated with enhanced chemosensitivity to 5-fluorouracil (5-FU) both in vitro and in vivo. Overexpression of AQP9 resulted in an increased intracellular level of 5-FU in CRC cells, hence leading to a higher percentage of apoptosis after 5-FU treatment. Moreover, AQP9 is positively associated with RAS activation and other downstream signaling molecules in CRC. AQP9 overexpression resulted in p21 upregulation and induced S-phase arrest. Taken together, AQP9 enhances the cytotoxic response to 5-FU in CRC cells by simultaneously inducing S-phase arrest via activation of RAS signaling and facilitating drug uptake. Our results suggest that AQP9 might be a novel predictor for the benefit of 5-FU-based chemotherapy in CRC. The identification of AQP9-induced tumor sensitivity to 5-FU highlights the role of AQP9 in regulating chemosensitivity in CRC.

Connecting cancer biology and clinical outcomes to imaging in KRAS mutant and wild-type colorectal cancer liver tumors following selective internal radiation therapy with yttrium-90

PURPOSE

To determine whether pathologic colorectal tumor KRAS mutation status is correlated with progression-free survival (PFS) by imaging after selective internal radiation therapy with Yttrium-90 (SIRT Y90) for metastatic colorectal cancer in the liver (mCRC).

MATERIALS AND METHODS

This was an IRB approved, HIPAA compliant retrospective cohort study. Consecutive patients with unresectable mCRC with documented KRAS mutation status treated at a single center from 2002 to 2013 with SIRT Y90 were investigated. Treatment response was compared between KRAS wild-type (wt) and mutant (mut) using an anatomic tumor response criteria based on RECIST 1.0. Kaplan-Meier estimation and Cox regression analysis were used to measure progression-free survival (PFS) and to assess independent prognostic factors for PFS.

RESULTS

82 of 186 patients met review criteria. 33 (40.2%) patients were identified as KRAS mut. PFS was longer in KRAS wt (median 166 days [95% CI 96-258 days]) vs. mut (median 91 days [95% CI 79-104 days], p = 0.002). KRAS mut patients were 1.48 times more likely to progress at first follow-up imaging than wt (95% CI 1.06-2.08, p = 0.024). Univariate analysis identified high pre-SIRT Y90 INR, KRAS wt, any use of anti-EGFR therapy, and post-SIRT Y90 chemotherapy as prognostic factors for longer PFS. In multivariate analysis, only KRAS wt was an independent prognostic factor for longer PFS (RR: 1.80 [95% CI 1.08-2.99], p = 0.024).

CONCLUSION

Longer PFS is associated with KRAS wt vs. mut following SIRT Y90.

The Influence of BRAF and KRAS Mutation Status on the Association between Aspirin Use and Survival after Colon Cancer Diagnosis

Background

Use of aspirin after diagnosis of colon cancer has been associated with improved survival. Identification of cancer subtypes that respond to aspirin treatment may help develop personalized treatment regimens. The aim of this study was to investigate the influence of BRAF and KRAS mutation status on the association between aspirin use and overall survival after colon cancer diagnosis.

Methods

A random selection of 599 patients with colon cancer were analyzed, selected from the Eindhoven Cancer Registry, and BRAF and KRAS mutation status was determined. Data on aspirin use (80 mg) were obtained from the PHARMO Database Network. Parametric survival models with exponential (Poisson) distribution were used.

Results

Aspirin use after colon cancer diagnosis was associated with improved overall survival in wild-type BRAF tumors, adjusted rate ratio (RR) of 0.60 (95% CI 0.44–0.83). In contrast, aspirin use in BRAF mutated tumors was not associated with an improved survival (RR 1.11, 95% CI 0.57–2.16). P-value for interaction was non-significant. KRAS mutational status did not differentiate in the association between aspirin use and survival.

Conclusion

Low-dose aspirin use after colon cancer diagnosis was associated with improved survival in BRAF wild-type tumors only. However, the large confidence interval of the rate ratio for the use of aspirin in patients with BRAF mutation does not rule out a possible benefit. These results preclude BRAF and KRAS mutation status to be used as a marker for individualized treatment with aspirin, if aspirin becomes regular adjuvant treatment for colon cancer patients in the future.

Up-Regulated Expression of SPRY4-IT1 Predicts Poor Prognosis in Colorectal Cancer

Background

Long non-coding RNA SPRY4 intronic transcript 1 (lncRNA SPRY4-IT1) has been reported to be associated with the progression of several cancers, but its expression level in colorectal cancer (CRC) has rarely been reported. The purpose of this study was to estimate the clinical significance of SPRY4-IT1 in CRC.

Material/Methods

The relative expression levels of SPRY4-IT1 were detected by quantitative real-time polymerase chain reaction (qRT-PCR) in diseased tissues and the adjacent normal tissues of 106 CRC patients. Chi-square method was used to evaluate the association between SPRY4-IT1 expression and the clinical features. Additionally, we assessed the overall survival at different expression levels of SPRY4-IT1 using Kaplan-Meier method. The prognostic significance of SPRY4-IT1 was estimated by Cox regression analysis.

Results

Up-regulated level of SPRY4-IT1 was detected in pathologic tissues of CRC patients compared with adjacent normal tissues (P=0.000). The relative expression of SPRY4-IT1 was associated with the tumor size, the depth of invasion, lymph node invasion, distant invasion, and tumor stage (P<0.05). Patients with high expression of SPRY4-IT1 had poor overall survival compared with those with high level (39.3 vs. 49.3 months, log-rank test, P=0.016). Cox regression analysis showed that SPRY4-IT1 could act as an independent prognostic factor in CRC (HR=2.341, 95% CI=1.136–4.826, P=0.021).

Conclusions

SPRY4-IT1 might be associated with tumorigenesis and progression of CRC, and it may be a promising biomarker for prognosis in patients with CRC.

Tumor suppressor genes in familial adenomatous polyposis

Colorectal cancer (CRC) is mostly due to a series of genetic alterations that are being greatly under the influence of the environmental factors. These changes, mutational or epigenetic modifications at transcriptional forefront and/or post-transcriptional effects via miRNAs, include inactivation and the conversion of proto-oncogene to oncogenes, and/or inactivation of tumor suppressor genes (TSG). Here, a thorough review was carried out on the role of TSGs with the focus on the APC as the master regulator, mutated genes and mal-/dysfunctional pathways that lead to one type of hereditary form of the CRC; namely familial adenomatous polyposis (FAP). This review provides a venue towards defining candidate genes that can be used as new PCR-based markers for early diagnosis of FAP. In addition to diagnosis, defining the modes of genetic alterations will open door towards genome editing to either suppress the disease or reduce its progression during the course of action.

Ginsenoside 20(S)-Rh2 exerts anti-cancer activity through targeting IL-6-induced JAK2/STAT3 pathway in human colorectal cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

Panax ginseng is one of the most well-known medicinal herbs in Korea and China, which has been used for treatment and prevention of cancer, obesity, diabetes, and cardiovascular diseases. Ginsenosides are the major components of P. ginseng, having a wide range of pharmacological activities. Among the ginsenosides, protopanaxadiol (PPD)-types reportedly have potent anti-cancer effects. Rh2 is PPD-type ginsenoside, and two stereoisomeric forms of Rh2 as 20(S)- and 20(R)-Rh2 were selectively isolated recently.

AIM OF THE STUDY

The biological activities of Rh2 ginsenosides are known to depend on their differences in stereochemistry. Colorectal cancer (CRC) is one of the most lethal neoplasm, and cancer-related death is usually associated with metastasis to other organs. We aimed this study to investigate whether 20(S)- and 20(R)-Rh2 can suppress tumor invasion in human CRC cells.

MATERIALS AND METHODS

20(S)- and 20(R)-Rh2 were isolated from the roots of ginseng. Human CRC cells were incubated with 20(S)- or 20(R)-Rh2 in the presence or absence of interleukin-6. An MTT assay was used to measure cell viability. Western blot and quantitative real-time PCR analyses were performed to determine levels of expression and phosphorylation. An invasion assay was performed using a Boyden chamber system with the Matrigel-coated membrane to measure cancer cell invasion.

RESULTS

20(S)- and 20(R)-Rh2 showed differential cytotoxic activity. Only 20(S)-Rh2 decreased cancer cell viability. Additionally, 20(S)-Rh2 effectively inhibited IL-6-induced signal transducer and activator of transcription 3 (STAT3) phosphorylation and the expression of matrix metalloproteinases (MMPs), including MMP-1, -2, and -9, resulting in inhibition of cancer cell invasion. Interestingly, these pharmacological activities of 20(S)-Rh2 were more potent than those of 20(R)-Rh2. Furthermore, combination treatment showed that 20(S)-Rh2 enhanced the sensitization of doxorubicin-treated anti-cancer activities in CRC cells.

CONCLUSION

Our results demonstrated that ginsenoside 20(S)-Rh2 has therapeutic potential for the treatment with CRC and may be valuable as a combination partner with more classic chemotherapeutic agents, such as doxorubicin, to treat CRC.

SNHG5 promotes colorectal cancer cell survival by counteracting STAU1-mediated mRNA destabilization

We currently have limited knowledge of the involvement of long non-coding RNAs (lncRNAs) in normal cellular processes and pathologies. Here, we identify and characterize SNHG5 as a stable cytoplasmic lncRNA with up-regulated expression in colorectal cancer. Depletion of SNHG5 induces cell cycle arrest and apoptosis in vitro and limits tumour outgrowth in vivo, whereas SNHG5 overexpression counteracts oxaliplatin-induced apoptosis. Using an unbiased approach, we identify 121 transcript sites interacting with SNHG5 in the cytoplasm. Importantly, knockdown of key SNHG5 target transcripts, including SPATS2, induces apoptosis and thus mimics the effect seen following SNHG5 depletion. Mechanistically, we suggest that SNHG5 stabilizes the target transcripts by blocking their degradation by STAU1. Accordingly, depletion of STAU1 rescues the apoptosis induced after SNHG5 knockdown. Hence, we characterize SNHG5 as a lncRNA promoting tumour cell survival in colorectal cancer and delineate a novel mechanism in which a cytoplasmic lncRNA functions through blocking the action of STAU1.

Several lncRNAs have been linked to cancer. Here, the authors identify SNHG5 as a long non-coding RNA promoting proliferation and survival of colorectal cancer cells by protecting specific mRNAs from STAU1-mediated degradation.

Chasing the personalized medicine dream through biomarker validation in colorectal cancer

Colorectal cancer (CRC) is a major health burden worldwide. The optimal approach to the diagnosis, management, and treatment of CRC involves multidisciplinary and integrated management practices. The field is rapidly changing because of recent advancements in delineating the molecular basis of tumorigenesis, introduction of targeted therapy, varied patient response to mainstay chemotherapeutics, biological drugs, and the effective combination regimes being used for treatment. Recent meta-analysis studies, which tend to establish few clinically useful predictor biomarkers, identify inconsistent results and limitations of the trials. Therefore, molecular pathological epidemiology discipline initiatives are promising. Here, we provide an overview of the potential of biomarker validation for personalized medicine by focusing largely on metastatic (m)CRC. We also highlight new candidate predictive and prognostic biomarkers.

Novel Biomarker Candidates for Colorectal Cancer Metastasis: A Meta-analysis of In Vitro Studies

Colorectal cancer (CRC) is one of the most common and lethal cancers. Although numerous studies have evaluated potential biomarkers for early diagnosis, current biomarkers have failed to reach an acceptable level of accuracy for distant metastasis. In this paper, we performed a gene set meta-analysis of in vitro microarray studies and combined the results from this study with previously published proteomic data to validate and suggest prognostic candidates for CRC metastasis. Two microarray data sets included found 21 significant genes. Of these significant genes, ALDOA, IL8 (CXCL8), and PARP4 had strong potential as prognostic candidates. LAMB2, MCM7, CXCL23A, SERPINA3, ABCA3, ALDH3A2, and POLR2I also have potential. Other candidates were more controversial, possibly because of the biologic heterogeneity of tumor cells, which is a major obstacle to predicting metastasis. In conclusion, we demonstrated a meta-analysis approach and successfully suggested ten biomarker candidates for future investigation.

Molecular Biomarkers of Colorectal Cancer and Cancer Disparities: Current Status and Perspective

This review provides updates on the efforts for the development of prognostic and predictive markers in colorectal cancer based on the race/ethnicity of patients. Since the clinical consequences of genetic and molecular alterations differ with patient race and ethnicity, the usefulness of these molecular alterations as biomarkers needs to be evaluated in different racial/ethnic groups. To accomplish personalized patient care, a combined analysis of multiple molecular alterations in DNA, RNA, microRNAs (miRNAs), metabolites, and proteins in a single test is required to assess disease status in a precise way. Therefore, a special emphasis is placed on issues related to utility of recently identified genetic and molecular alterations in genes, miRNAs, and various "-omes" (e.g., proteomes, kinomes, metabolomes, exomes, methylomes) as candidate molecular markers to determine cancer progression (disease recurrence/relapse and metastasis) and to assess the efficacy of therapy in colorectal cancer in relation to patient race and ethnicity. This review will be useful for oncologists, pathologists, and basic and translational researchers.

Systems medicine in colorectal cancer: from a mathematical model toward a new type of clinical trial

Current colorectal cancer (CRC) treatment guidelines are primarily based on clinical features, such as cancer stage and grade. However, outcomes may be improved using molecular treatment guidelines. Potentially useful biomarkers include driver mutations and somatically inherited alterations, signaling proteins (their expression levels and (post) translational modifications), mRNAs, micro‐RNAs and long noncoding RNAs. Moving to an integrated system is potentially very relevant. To implement such an integrated system: we focus on an important region of the signaling network, immediately above the G1‐S restriction point, and discuss the reconstruction of a Molecular Interaction Map and interrogating it with a dynamic mathematical model. Extensive model pretraining achieved satisfactory, validated, performance. The model helps to propose future target combination priorities, and restricts drastically the number of drugs to be finally tested at a cellular, in vivo, and clinical‐trial level. Our model allows for the inclusion of the unique molecular profiles of each individual patient's tumor. While existing clinical guidelines are well established, dynamic modeling may be used for future targeted combination therapies, which may progressively become part of clinical practice within the near future. WIREs Syst Biol Med 2016, 8:314–336. doi: 10.1002/wsbm.1342

This article is categorized under: 1

Biological Mechanisms > Cell Signaling

2

Analytical and Computational Methods > Computational Methods

3

Translational, Genomic, and Systems Medicine > Translational Medicine

Cell Line Derived 5-FU and Irinotecan Drug-Sensitivity Profiles Evaluated in Adjuvant Colon Cancer Trial Data

PURPOSE

This study evaluates whether gene signatures for chemosensitivity for irinotecan and 5-fluorouracil (5-FU) derived from in vitro grown cancer cell lines can predict clinical sensitivity to these drugs.

METHODS

To test if an irinotecan signature and a SN-38 signature could identify patients who benefitted from the addition of irinotecan to 5-FU, we used gene expression profiles based on cell lines and clinical tumor material. These profiles were applied to expression data obtained from pretreatment formalin fixed paraffin embedded (FFPE) tumor tissue from 636 stage III colon cancer patients enrolled in the PETACC-3 prospective randomized clinical trial. A 5-FU profile developed similarly was assessed by comparing the PETACC-3 cohort with a cohort of 359 stage II colon cancer patients who underwent surgery but received no adjuvant therapy.

RESULTS

There was no statistically significant association between the irinotecan or SN-38 profiles and benefit from irinotecan. The 5-FU sensitivity profile showed a statistically significant association with relapse free survival (RFS) (hazard ratio (HR) = 0.54 (0.41-0.71), p<1e-05) and overall survival (HR = 0.47 (0.34-0.63), p<1e-06) in the PETACC-3 subpopulation. The effect of the 5-FU profile remained significant in a multivariable Cox Proportional Hazards model, adjusting for several relevant clinicopathological parameters. No statistically significant effect of the 5-FU profile was observed in the untreated cohort of 359 patients (relapse free survival, p = 0.671).

CONCLUSION

The irinotecan predictor had no predictive value. The 5-FU predictor was prognostic in stage III patients in PETACC-3 but not in stage II patients with no adjuvant therapy. This suggests a potential predictive ability of the 5-FU sensitivity profile to identify colon cancer patients who may benefit from 5-FU, however, any biomarker predicting benefit for adjuvant 5-FU must be rigorously evaluated in independent cohorts. Given differences between the two study cohorts, the present results should be further validated.

The Prognostic Value of Microsatellite Instability, KRAS, BRAF and PIK3CA Mutations in Stage II Colon Cancer Patients

In the era of personalized cancer medicine, identifying mutations within patient tumors plays an important role in defining high-risk stage II colon cancer patients. The prognostic role of BRAF V600E mutation, microsatellite instability (MSI) status, KRAS mutation and PIK3CA mutation in stage II colon cancer patients is not settled. We retrospectively analyzed 186 patients with stage II colon cancer who underwent an oncological resection but were not treated with adjuvant chemotherapy. KRAS mutations, PIK3CA mutation, V600E BRAF mutation and MSI status were determined. Survival analyses were performed. Mutations were found in the patients with each mutation in the following percentages: 23% (MSI), 35% (KRAS), 19% (BRAF) and 11% (PIK3CA). A trend toward worse overall survival (OS) was seen in patients with an MSI (5-year OS 74% versus 82%, adjusted hazard ratio [HR] 1.8, 95% confidence interval [CI] 0.6-4.9) and a KRAS-mutated tumor (5-year OS 77% versus 82%, adjusted HR 1.7, 95% CI 0.8-3.5). MSI and BRAF-mutated tumors tended to correlate with poorer disease-free survival (DFS) (5-year DFS 60% versus 78%, adjusted HR 1.6, 95% CI 0.5-2.1 and 5-year DFS 57% versus 77%, adjusted HR 1.1, 95% CI 0.4-2.6 respectively). In stage II colon cancer patients not treated with adjuvant chemotherapy, BRAF mutation and MSI status both tended to have a negative prognostic effect on disease-free survival. KRAS and MSI status also tended to be correlated with worse overall survival.

Association of perioperative blood pressure with long-term survival in rectal cancer patients

Background

Several studies suggested that hypertension is positively related to cancer incidence and mortality. In this study, we investigated the association between perioperative blood pressure (BP) and long-term survival outcomes in patients with rectal cancer.

Methods

This study included a cohort of 358 patients with stages I–III rectal cancer who underwent a curative resection between June 2007 and June 2011. Both pre- and postoperative BPs were measured, by which patients were grouped (low BP: <120/80 mmHg; high BP: ≥120/80 mmHg). The survival outcomes were compared between these two groups. The primary endpoints were disease-free survival (DFS) and cancer-specific survival (CSS).

Results

Univariate analysis showed that patients with high preoperative systolic BP had lower 3-year DFS (67.2% vs. 82.1%, P = 0.041) and CSS rates (81.9% vs. 94.8%, P = 0.003) than patients with low preoperative systolic BP, and the associations remained significant in the Cox multivariate analysis, with the adjusted hazard ratios equal to 1.97 [95% confidence interval (CI) = 1.08–3.60, P = 0.028] and 2.85 (95% CI = 1.00–8.25, P = 0.050), respectively. Similarly, in postoperative evaluation, patients with high systolic BP had significantly lower 3-year CSS rates than those with low systolic BP (78.3% vs. 88.9%, P = 0.032) in univariate analysis. Moreover, high pre- and/or postoperative systolic BP presented as risk factors for CSS in the subgroups of patients who did not have a history of hypertension, with and/or without perioperative administration of antihypertensive drugs.

Conclusions

High preoperative systolic BP was an independent risk factor for both CSS and DFS rates, and high postoperative systolic BP was significantly associated with a low CSS rate in rectal cancer patients. Additionally, our results suggest that rectal cancer patients may get survival benefit from BP control in perioperative care. However, further studies should be conducted to determine the association between BP and CSS and targets of BP control.

Locally advanced rectal cancers with simultaneous occurrence of KRAS mutation and high VEGF expression show invasive characteristics

In this study, we investigated the mutation status of KRAS gene in pretherapeutic and preoperative biopsies in 63 specimens of locally advanced rectal cancers in order to evaluate its potential predictive and/or prognostic role. Regions of interest of KRAS exon 2 were amplified and visualized on 2% agarose gel. Obtained PCR products were subjected to direct sequencing. KRAS mutations were detected in 35% of patients, 91% of which were located in codon 12 and 9% in codon 13. In general, KRAS mutation status did not affect the response to neoadjuvant chemoradiotherapy (CRT). However, patients harboring mutated KRAS gene, simultaneously with high vascular endothelial growth factor (VEGF) expression, exhibited a worse response to CRT (p=0.030), a more frequent appearance of local recurrences and distant metastasis (p=0.003), and shorter overall survival (p=0.001) compared to all others. On the contrary, patients with GGT>GCT KRAS mutation exhibited a significantly better response to CRT than those with any other type of KRAS mutation (p=0.017). Moreover, the presence of GGT>GCT mutation was associated with low VEGF and Ki67 expression (p=0.012 in both cases), parameters related to less aggressiveness of the disease. Our results suggest that KRAS mutation status could have some predictive and prognostic importance in rectal cancer when analyzed together with other parameters, such as VEGF and Ki67 expression. In addition, it seems that not only the presence but the type of KRAS mutation is important for examining its impact on CRT response.