Discovery of colorectal cancer PIK3CA mutation as potential predictive biomarker: power and promise of molecular pathological epidemiology

Determination of the frequency and distribution of APC, PIK3CA, and SMAD4 gene mutations in Ugandan patients with colorectal cancer

Uganda is a developing low-income country with a low incidence of colorectal cancer, which is steadily increasing. Ugandan colorectal cancer (CRC) patients are young and present with advanced-stage disease. In our population, there is a scarcity of genetic oncological studies, therefore, we investigated the mutational status of CRC tissues, focusing in particular on the adenomatous polyposis coli (APC), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), and SMAD4 genes. Our objective was to determine whether there were any differences between other populations and Ugandan patients. We performed next-generation sequencing on the extracted DNA from formalin-fixed paraffin-embedded adenocarcinoma samples from 127 patients (mean (SD) age: 54.9 (16.0) years; male:female sex ratio: 1.2:1). Most tumours were located in the rectum 56 (44.1%), 14 (11%) tumours were high grade, and 96 (75.6%) were moderate grade CRC. Stage III + IV CRC tumours were found in 109 (85.8%) patients. We identified 48 variants of APC, including 9 novel APC mutations that were all pathogenic or deleterious. For PIK3CA, we found 19 variants, of which 9 were deleterious or pathogenic. Four PIK3CA novel pathogenic or deleterious variants were included (c.1397C > G, c.2399_2400insA, c.2621G > C, c.2632C > G). Three SMAD4 variants were reported, including two pathogenic or deleterious variants (c.1268G > T, c.556dupC) and one tolerant (c.563A > C) variant. One novel SMAD4 deleterious mutation (c.1268G > T) was reported. In conclusion, we provide clinicopathological information and new genetic variation data pertinent to CRC in Uganda.

A Contemporary Review on the Critical Role of Nonsteroidal Anti-inflammatory Agents in Colorectal Cancer Therapy

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) are widely recognized as effective pain relievers and function by inhibiting the cyclooxygenase enzyme (COXs). Moreover, they have been found to participate in various cellular processes through different signaling pathways, such as WNT, MAPK, NF-κB, and PI3K/AKT/mTOR. This makes them potential candidates for chemoprevention of several malignancies, particularly colorectal cancer (CRC). However, the use of NSAIDs in cancer prevention and treatment is a complex issue due to their adverse effects and gastrointestinal toxicity. Therefore, it is crucial to explore combination therapies that can minimize side effects while maximizing synergistic effects with other agents and to evaluate the success rate of such approaches in both pre-clinical and clinical studies. In this review, we aim to provide an overview of the effects of NSAIDs in the prevention and treatment of CRC. We will focus on elucidating the possible mechanisms of action of these drugs, the signaling pathways involved in CRC, and the potential synergistic effects when combined with other therapeutic agents.

Cordycepin and kinase inhibition in cancer

Cordycepin, a nucleoside from Cordyceps mushrooms, has many beneficial properties for health, including anticancer activities. In cancer cells, cordycepin targets various signaling molecules. Here, we review the possible anticancer mechanisms of cordycepin involving the targeting of kinases. Abnormal kinase expression is involved in cancer development and progression through different molecular mechanisms, including phosphorylation, amplification, genetic mutations, and epigenetic regulation. Research suggests that kinases, such as the c-Jun N-terminal kinase (JNK), mitogen-activated protein kinase (MAPK), AMP kinase (AMPK), phosphoinositide 3-kinase (PI3K)/Akt, extracellular signal-regulated kinase (ERK), mammalian target of rapamycin (mTOR), glycogen synthase kinase (GSK)-3β, and focal adhesion kinase (FAK) pathways, can be targeted by cordycepin and disrupting their activity. Given that kinase inhibitors can have crucial roles in cancer treatment, targeting kinases might be one of the molecular mechanisms involved in the anticancer potential of cordycepin.

Restoration of Altered Oncogenic and Tumor Suppressor microRNA Expression in Breast Cancer and Colorectal Cancer Cell using Epicatechin

BACKGROUND

MicroRNAs (miRNA) are small non-coding RNAs that regulate the function of mRNA post-transcriptionally in a tissue-specific manner. miRNA expressions are heavily dysregulated in human cancer cells through various mechanisms, including epigenetic changes, karyotype abnormalities, and miRNA biogenesis defects. miRNAs may act as either oncogenes or tumor suppressors under different conditions. Epicatechin is a natural compound found in green tea which possesses antioxidant and antitumor properties.

OBJECTIVE

The objective of this study is to investigate the effect of epicatechin treatment on the expression level of several oncogenic and tumor suppressor miRNAs in breast and colorectal cancer cell lines (MCF7 and HT-29) and identify its mechanism of action.

METHODS

The MCF-7 and HT29 cells were treated with epicatechin for 24 hours and untreated cells were considered control cultures. miRNA was isolated and qRT-PCR was used to measure the expression profile changes of different oncogenic and tumor suppressor miRNAs. Furthermore, the mRNA expression profile was also screened at different concentrations of epicatechin.

RESULTS

Our results showed several-fold changes in miRNAs expression level, which is cell line specific. Also, epicatechin at different concentrations induces biphasic changes in mRNA expression levels in both cell lines.

CONCLUSION

Our findings first time demonstrated that epicatechin can reverse the expression of these miRNAs and may trigger the cytostatic effect at a lower concentration.

Crosstalk between PI3K/Akt and Wnt/β-catenin pathways promote colorectal cancer progression regardless of mutational status

The PI3K/Akt and Wnt/β-catenin pathways play an important role in the acquisition of the malignant phenotype in cancer. However, there are few data regarding the role of the interplay between both pathways in colorectal cancer (CRC) progression. The mutational status and the clinicopathological characteristics of PI3K/Akt and Wnt/β-catenin pathways were accessed by bioinformatic analysis whereas that the impact of the interplay between the activity of both pathways to explain tumorigenic potential was performed in vitro using IGF-1 and Wnt3a treatments in CRC cell models. The mutational status of these pathways did not influence the survival of CRC patients, but an association between clinicopathological characteristics in patients with mutations in one, but not in both pathways was observed. A potentiating effect on the activation of both pathways and enhanced cellular migration and proliferation was observed when both pathways were activated simultaneously with IGF-1 and Wnt3a. In addition, these effects were hindered after pretreatment with LY294002, a specific PI3K inhibitor, suggesting some dependence between these two signaling cascades. Our findings show that, regardless of mutational status, there is an interplay between the activity of PI3K/Akt and Wnt/β-catenin pathways that contributes to events related to CRC progression and that the reversal of such events using a PI3K inhibitor highlights the value of targeting these pathways for potential directed therapies in CRC patients.

Elucidation of the mechanism of action of Runyan Mixture in the treatment of pharyngitis using a network pharmacological approach

This study aimed to elucidate the mechanism of action of Runyan Mixture in treating pharyngitis using a network pharmacological approach. The active components of the Runyan Mixture were obtained from the traditional chinese medicine systems pharmacology database and evaluated using Lipinski's rules. The SwissTargetPrediction database was used to predict the action targets of the Runyan Mixture, and a protein-protein interaction network was constructed using the STRING database. Moreover, the anti-inflammatory effect of Runyan Mixture was validated in vitro using the lipopolysaccharide induced inflammation in macrophages. The Runyan Mixture was the liquid preparation from 8 traditional Chinese medicine. A total of 89 types of active components, 53 core targets, and 98 signaling pathways (P < .001) were identified for the Runyan Mixture. The main action targets were EGFR, MAPK1, AKT1, PIK3CA, NFKB1, SRC, TNF, MAPK8, MET, and PTGS2. Among the identified signaling pathways, 20 were associated with microbial infection and 24 were related to the immune-inflammatory response. Experimental results in vitro showed that Runyan Mixture could significantly inhibit the expression of interleukin-1, interleukin-6, and tumor necrosis factor-α (P < .05) in macrophages by lipopolysaccharide stimulation. Based on the results of the protein-protein interaction network analysis and the anti-inflammatory effect in vitro, the efficiency of the Runyan Mixture in pharyngitis treatment could be attributed to the inhibition of the inflammatory response.

Interaction of Gut Microbiota with Endocrine Homeostasis and Thyroid Cancer

The gut microbiota plays a crucial role in healthy individuals as well as in patients with thyroid diseases, including thyroid cancer. Although the prognosis of differentiated thyroid cancer is predictable, that of some poorly differentiated, medullary, and anaplastic thyroid cancers remains unpromising. As the interaction between the gut microbiota and thyroid cancer has been gradually revealed in recent years, the thyroid gland, a crucial endocrine organ, is shown to have a complex connection with the body's metabolism and is involved in inflammation, autoimmunity, or cancer progression. Dysbiosis of the gut microbiota and its metabolites can influence changes in hormone levels and susceptibility to thyroid cancer through multiple pathways. In this review, we focus on the interactions of the gut microbiota with thyroid function diseases and thyroid cancer. In addition, we also discuss some potential new strategies for the prevention and treatment of thyroid disease and thyroid cancer. Our aim is to provide some possible clinical applications of gut microbiota markers for early diagnosis, treatment, and postoperative management of thyroid cancer. These findings were used to establish a better multi-disciplinary treatment and prevention management strategy and to individualize the treatment of patients in relation to their gut microbiota composition and pathological characteristics.

Personalizing first-line treatment in advanced colorectal cancer: Present status and future perspectives

BACKGROUND

Colorectal cancer is one of the most frequent neoplasms worldwide, and the majority of patients are diagnosed in advanced stages. Metastatic colorectal cancer (mCRC) harbors several mutations with different prognostic and predictive values; KRAS, NRAS, and BRAF mutations are the best known. Indeed, RAS and BRAF molecular status are associated with a different response to monoclonal antibodies (Anti-epidermal growth factor receptor and anti-vascular endothelial growth factor receptor agents), which are usually added to chemotherapy in first-line, and thus allow to select the optimal therapy for patients with mCRC. Furthermore, sidedness is an important predictive and prognostic factor in mCRC, which is explained by the different molecular profile of left and right-sided tumors. Recently, microsatellite instability-high has emerged as a predictive factor of response and survival from immune checkpoint inhibitors in mCRC. Finally, several other alterations have been described in lower frequencies, such as human epidermal growth factor receptor-2 overexpression/amplification, PIK3CA pathway alterations, phosphatase and tension homolog loss, and hepatocyte growth factor/mesenchymal-epithelial transition factor pathway dysregulation, with several targeted therapies already demonstrating activity or being tested in currently ongoing clinical trials.

AIM

To review the importance of studying the predictive and prognostic roles of the molecular profile of mCRC, the changes occurred in recent years and how they would potentially change in the near future, to guide physicians in treatment decisions.

RELEVANCE FOR PATIENTS

Today, several different therapeutic options can be offered to patients in the first-line setting of mCRC. Therapies at present approved or under investigation in clinical trials will be thoroughly reviewed, with special emphasis on the molecular rationale behind them. Understanding the molecular status, resistance mechanisms and potential new druggable targets may allow physicians to choose the best therapeutic option in the first-line mCRC.

Computational approaches leveraging integrated connections of multi-omic data toward clinical applications

In line with the advances in high-throughput technologies, multiple omic datasets have accumulated to study biological systems and diseases coherently. No single omics data type is capable of fully representing cellular activity. The complexity of the biological processes arises from the interactions between omic entities such as genes, proteins, and metabolites. Therefore, multi-omic data integration is crucial but challenging. The impact of the molecular alterations in multi-omic data is not local in the neighborhood of the altered gene or protein; rather, the impact diffuses in the network and changes the functionality of multiple signaling pathways and regulation of the gene expression. Additionally, multi-omic data is high-dimensional and has background noise. Several integrative approaches have been developed to accurately interpret the multi-omic datasets, including machine learning, network-based methods, and their combination. In this review, we overview the most recent integrative approaches and tools with a focus on network-based methods. We then discuss these approaches according to their specific applications, from disease-network and biomarker identification to patient stratification, drug discovery, and repurposing.

LINC02163 promotes colorectal cancer progression via miR-511-3p/AKT3 axis

Long non-coding RNAs and microRNAs are functional regulators in tumour progression. Herein, we revealed the level LINC02163 was up-regulated in CRC tissues and cell lines, and the expression of LINC02163 negatively correlated with prognosis of CRC patients. Functional experiments demonstrated knockdown of LINC02163 significantly attenuated CRC cells proliferation and metastasis. Mechanism analysis showed miR-511-3p could bind LINC02163 and AKT3, and the expressional level of miR-511-3p negatively correlated with the abundance of LINC02163 and AKT3. Inhibition of LINC02163 suppressed cell proliferation, while transfection of miR-511-3p inhibitor or AKT3 in LINC02163-depletion cells restored cell growth and abolished the cell cycle arrest in G0/G1 phase. Therefore, it was indicated that LINC02163 exerted pro-tumour effect through miR-511-3p/AKT3 axis and was prognostic marker for colorectal cancer.

Updates on the molecular mechanisms of aspirin in the prevention of colorectal cancer: Review

Colorectal cancer is one of the commonest malignancies worldwide. The estimated lifetime risk of the disease is about 5% with an incidence of one million new cases and 600,000 deaths worldwide every year. It is estimated that in 2019, approximately 134,490 new cases of colorectal cancer will be diagnosed with 49,190 mortalities. Though the disease is regarded as a disorder of the more developed world, the occurrence is steadily increasing in many developing countries. Since chronic inflammation is a known aggravating risk factor for colorectal cancer, anti-inflammatory agents such as aspirin have been used to prevent the development of colorectal cancer and related mortality. The potential mechanisms for the effect of aspirin in the prevention of colorectal cancer have been proposed and broadly classified as cyclooxygenase (COX) dependent and COX-independent. Some of the primary effectors of COX-dependent mechanisms in carcinogenesis are likely to be prostaglandins. In contrast to the reversible action of other nonsteroidal anti-inflammatory drugs, aspirin is known to irreversibly inactivate COX enzymes to suppress production of prostaglandins. COX-independent mechanisms of anticancer effects of aspirin include down-regulation of nuclear factor kappa B activity and Akt activation, modulation of Bcl-2 and Bax family proteins, suppression of vascular endothelial growth factor, induction of apoptosis, disruption of DNA repair mechanisms, and induction of spermidine/spermine N¹-acetyltransferase that modulates polyamine catabolism.

Molecular targets of Yangyin Fuzheng Jiedu Prescription in the treatment of hepatocellular carcinoma based on network pharmacology analysis

Background

Yangyin Fuzheng Jiedu Prescription (YFJP) is a traditional Chinese medicine (TCM) indicated for the treatment of hepatocellular carcinoma (HCC). Its potential targets and molecular mechanisms are not clear. Therefore, this study intends to explore the molecular mechanism of YFJP based on network pharmacology analysis and in vitro validation.

Methods and results

Through univariate and multivariate analyses and survival analysis in HCC patients with or without YFJP treatment we found that drinking alcohol, alfafeto protein ≥ 400 ng/l, baseline portal vein tumor thrombus and total bilirubin level ≥ 18.8 μM) were independent risk factors for poor prognosis, while red blood cell count ≥ 4 × 10⁹/l and TCM treatment were independent protective factors. Besides, YFJP prolonged the cumulative survival of HCC patients. Using online pharmacological methods, we obtained 58 relevant compounds and molecular 53 targets. By using scratch test, Transwell assay, EdU assay, and TUNEL staining, we found that YFJP-containing serum repressed the migration, invasion and proliferation of HCC cells in vitro, and induced cell apoptosis. Moreover, YFJP diminished the gene expression of TP53, CCND1, p-EGFR, EGF, VEGFA, JUN, IL6, COX-2, AKT1, and MAPK1 in HCC cells, but elevated the expression of ESR1 and CASP3.

Conclusions

Taken together, results showed that YFJP attenuated HCC progression through mediating effects on HCC-related genes.

Frequency and coexistence of KRAS, NRAS, BRAF and PIK3CA mutations and occurrence of MMR deficiency in Danish colorectal cancer patients

The MAPK signalling genes KRAS, NRAS and BRAF and the PIK3CA gene are routinely investigated for mutations in the diagnostic routine of colorectal cancer. Few studies have reported co-existing mutations in these genes with clinical relevance, while some have been previously regarded as mutually exclusive. We set to investigate the frequency and co-occurrent mutations in these targets, and the occurrence of mismatch repair deficiency (dMMR) in a large cohort of Danish colorectal cancers. 1000 colorectal tumours were sequenced as part of our diagnostic workflow for KRAS, NRAS, BRAF and PIK3CA mutations using next-generation sequencing (NGS) and analysed by immunohistochemistry (IHC) for loss of the MMR proteins, MLH1, PMS2, MSH2 and MSH6. Co-existing mutations in 12 patients (1.2%) occurred as multiple mutations in the same gene or spread across several genes (KRAS, NRAS and/or BRAF). The frequency of single mutations in the genes occurred with a frequency similar to previously reported, except for a higher frequency of BRAF mutations (18.0%). We found dMMR in 14.6% of the cases with a majority lacking expression of both MLH1 and PMS2. BRAF mutations were only present in dMMR cases involving MLH1 and/or PMS2. Our findings suggest that co-existing mutations occur, except for the hotspot BRAF V600E, which is mutually exclusive with KRAS/NRAS mutations. Therefore, instead of single gene alterations from the MAPK signalling, assessing co-occurrence of mutations within one or more of those genes should also be accounted. This may impact future oncological treatments and should be considered in the diagnostic workflow.

Colorectal liver metastases: Current management and future perspectives

The liver is the commonest site of metastatic disease for patients with colorectal cancer, with at least 25% developing colorectal liver metastases (CRLM) during the course of their illness. The management of CRLM has evolved into a complex field requiring input from experienced members of a multi-disciplinary team involving radiology (cross sectional, nuclear medicine and interventional), Oncology, Liver surgery, Colorectal surgery, and Histopathology. Patient management is based on assessment of sophisticated clinical, radiological and biomarker information. Despite incomplete evidence in this very heterogeneous patient group, maximising resection of CRLM using all available techniques remains a key objective and provides the best chance of long-term survival and cure. To this end, liver resection is maximised by the use of downsizing chemotherapy, optimisation of liver remnant by portal vein embolization, associating liver partition and portal vein ligation for staged hepatectomy, and combining resection with ablation, in the context of improvements in the functional assessment of the future remnant liver. Liver resection may safely be carried out laparoscopically or open, and synchronously with, or before, colorectal surgery in selected patients. For unresectable patients, treatment options including systemic chemotherapy, targeted biological agents, intra-arterial infusion or bead delivered chemotherapy, tumour ablation, stereotactic radiotherapy, and selective internal radiotherapy contribute to improve survival and may convert initially unresectable patients to operability. Currently evolving areas include biomarker characterisation of tumours, the development of novel systemic agents targeting specific oncogenic pathways, and the potential re-emergence of radical surgical options such as liver transplantation.

STX2 drives colorectal cancer proliferation via upregulation of EXOSC4

AIMS

To explore the biological function and mechanism of Syntaxin2 (STX2) in Colorectal cancer (CRC) proliferation.

MAIN METHODS

A series of gain- and loss-of-function analysis were conducted the to explore the biological function of STX2 in CRC proliferation in vivo and in vitro. Western blot, Co-immunoprecipitation (Co-IP) and the functional analyses were taken to analyze the regulative role of STX2 on Exosome Complex 4 (EXOSC4) in CRC proliferation; Immunohistochemistry (IHC) and Real-time quantitative polymerase chain reaction (qPCR) were used to further verify the relationship between the expression of STX2 and EXOSC4 in human CRC samples.

KEY FINDINGS

Our study revealed that the over-expression of STX2 promoted CRC proliferation, while knockdown of STX2 repressed CRC proliferation; STX2 promoted CRC proliferation via increasing EXOSC4 protein; There was a positive correlation between STX2 and EXOSC4 expression.

SIGNIFICANCE

The current data verify that STX2 drives the proliferation of CRC via increasing the expression of EXOSC4.

Chondroprotective Effects of Combination Therapy of Acupotomy and Human Adipose Mesenchymal Stem Cells in Knee Osteoarthritis Rabbits via the GSK3β-Cyclin D1-CDK4/CDK6 Signaling Pathway

Adipose-derived stem cells (ASCs) are highly chondrogenic and can be used to treat knee osteoarthritis (KOA) by alleviating cartilage defects. Acupotomy, a biomechanical therapy guided by traditional Chinese medicine theory, alleviates cartilage degradation and is widely used in the clinic to treat KOA by correcting abnormal mechanics. However, whether combining acupotomy with ASCs will reverse cartilage degeneration by promoting chondrocyte proliferation in KOA rabbits is unknown. The present study aimed to investigate the effects of combination therapy of acupotomy and ASCs on chondrocyte proliferation and to determine the underlying mechanism in rabbits with KOA induced by knee joint immobilization for 6 weeks. After KOA modeling, five groups of rabbits (acupotomy, ASCs, acupotomy + ASCs, model and control groups) received the indicated intervention for 4 weeks. The combination therapy significantly restored the KOA-induced decrease in passive range of motion (PROM) in the knee joint and reduced the elevated serum level of cartilage oligomeric matrix protein (COMP), a marker for cartilage degeneration. Furthermore, magnetic resonance imaging (MRI) and scanning electron microscopy (SEM) images showed that the combination therapy inhibited cartilage injury. The combination therapy also significantly blocked increases in the mRNA and protein expression of glycogen synthase kinase-3β (GSK3β) and decreases in the mRNA and protein expression of cyclin D1/CDK4 and cyclin D1/CDK6 in cartilage. These findings indicated that the combination therapy mitigated knee joint immobility, promoted chondrocyte proliferation and alleviated cartilage degeneration in KOA rabbits, and these effects may be mediated by specifically regulating the GSK3β-cyclin D1-CDK4/CDK6 pathway.

IGF-1R inhibition induces MEK phosphorylation to promote survival in colon carcinomas

The insulin-like growth factor 1 receptor (IGF-1R) governs several signaling pathways for cell proliferation, survival, and anti-apoptosis. Thus, targeting IGF-1R appears as a reasonable rationale for tumor treatment. However, clinical studies showed that inhibition of IGF-1R has very limited efficacy due to the development of resistance to IGF-1R blockade in tumor cells. Here, we discovered that prolonged treatment of colon cancer cells with IGF-1R inhibitors (BMS-754807 and GSK1838705A) stimulates p70 KDa ribosomal protein S6 kinase 1 (p70S6K1) activation, a well-known kinase signaling for cell survival. We also found that p70S6K1 activation by IGF-1R inhibition is independent of K-Ras and PIK3CA mutations that frequently occur in colon cancer. Besides the increased p70S6K1 phosphorylation, the phosphorylation of mitogen-activated protein kinase kinase 1 and 2 (MEK1/2) was elevated in the cells treated with BMS-754807. Interestingly, the increases in MEK1/2 and p70S6K1 phosphorylation were also observed when cells were subjected to the treatment of AKT inhibitor or genetic knockdown of AKT2 but not AKT1, suggesting that AKT2 inhibition stimulates MEK1/2 phosphorylation to activate p70S6K1. Conversely, inhibition of MEK1/2 by MEK1/2 inhibitor (U0126) or knockdown of MEK1 and MEK2 by corresponding mek1 and mek2 siRNA enhanced AKT phosphorylation, indicating mutual inhibition between AKT and MEK. Furthermore, the combination of BMS-754807 and U0126 efficiently decreased the cell viability and increased cleaved caspase 3 and apoptosis in vitro and in vivo. Our data suggest that the treatment of colon tumor cells with IGF-1R inhibitors stimulates p70S6K1 activity via MEK1/2 to promote survival, providing a new strategy for colorectal cancer therapeutics.

Upregulation of OSBPL3 by HIF1A promotes colorectal cancer progression through activation of RAS signaling pathway

Oxysterol-binding protein like protein 3 (OSBPL3) has been shown involving in the development of several human cancers. However, the relationship between OSBPL3 and colorectal cancer (CRC), particularly the role of OSBPL3 in the proliferation, invasion and metastasis of CRC remains unclear. In this study, we investigated the role of OSBPL3 in CRC and found that its expression was significantly higher in CRC tissues than that in normal tissues. In addition, high expression of OSBPL3 was closely related to poor differentiation, advanced TNM stage and poor prognosis of CRC. Further experiments showed that over-expression of OSBPL3 promoted the proliferation, invasion and metastasis of CRC in vitro and in vivo models. Moreover, we revealed that OSBPL3 promoted CRC progression through activation of RAS signaling pathway. Furthermore, we demonstrated that hypoxia induced factor 1 (HIF-1A) can regulate the expression of OSBPL3 via binding to the hypoxia response element (HRE) in the promoter of OSBPL3. In summary, Upregulation of OSBPL3 by HIF1A promotes colorectal cancer progression through activation of RAS signaling pathway. This novel mechanism provides a comprehensive understanding of both OSBPL3 and the RAS signaling pathway in the progression of CRC and indicates that the HIF1A–OSBPL3–RAS axis is a potential target for early therapeutic intervention in CRC progression.

A review of big data and medical research

Universally, the volume of data has increased, with the collection rate doubling every 40 months, since the 1980s. "Big data" is a term that was introduced in the 1990s to include data sets too large to be used with common software. Medicine is a major field predicted to increase the use of big data in 2025. Big data in medicine may be used by commercial, academic, government, and public sectors. It includes biologic, biometric, and electronic health data. Examples of biologic data include biobanks; biometric data may have individual wellness data from devices; electronic health data include the medical record; and other data demographics and images. Big data has also contributed to the changes in the research methodology. Changes in the clinical research paradigm has been fueled by large-scale biological data harvesting (biobanks), which is developed, analyzed, and managed by cheaper computing technology (big data), supported by greater flexibility in study design (real-world data) and the relationships between industry, government regulators, and academics. Cultural changes along with easy access to information via the Internet facilitate ease of participation by more people. Current needs demand quick answers which may be supplied by big data, biobanks, and changes in flexibility in study design. Big data can reveal health patterns, and promises to provide solutions that have previously been out of society's grasp; however, the murkiness of international laws, questions of data ownership, public ignorance, and privacy and security concerns are slowing down the progress that could otherwise be achieved by the use of big data. The goal of this descriptive review is to create awareness of the ramifications for big data and to encourage readers that this trend is positive and will likely lead to better clinical solutions, but, caution must be exercised to reduce harm.

Prognostic value of molecular biomarkers in patients with metastatic colorectal cancer: a real-world study

PURPOSE

Outcomes for patients with metastatic colorectal cancer (mCRC) have been improved by the identification of biomarkers predictive and prognostic of clinical outcome. The present retrospective analysis was undertaken to assess the utility of key biomarkers and clinical parameters in predicting outcomes in Spanish patients with mCRC.

METHODS

We retrospectively analyzed tumor samples from a series of patients aged > 18 years with mCRC who were treated at the Hospital General Universitario Gregorio Marañón Spain. Real-time polymerase chain reaction was used to detect KRAS, NRAS, BRAF, and PIK3CA mutations. The key outcome of interest was overall survival (OS). Survival curves were estimated using the Kaplan-Meier method and stratified by the variables of greatest clinical interest. Differences were tested using the log-rank test.

RESULTS

Median OS in the overall population was 24.4 months. Triple WT patients (WT KRAS, NRAS, and BRAF) and quadruple WT patients (WT KRAS, NRAS, BRAF, and PIK3CA) had significantly better OS than those who did not have triple or quadruple WT tumors. OS was significantly better in patients with left- vs. right-sided tumors, patients with resected primary tumors and metastases vs. those without resection, and patients with isolated hepatic and isolated pulmonary metastases.

CONCLUSIONS

This retrospective, observational study has confirmed the prognostic value of the location and resection status of the primary tumor and metastases in Spanish patients with mCRC. Triple WT status, in particular, was prognostic in this patient population, with PIK3CA adding to the prognostic value in the quadruple WT population.

Colorectal cancer occurrence and treatment based on changes in intestinal flora

Colorectal cancer (CRC) is the most common cancer in the world, and its incidence has been increasing in recent years. The occurrence of CRC is believed to be related to a variety of factors. Epidemiological data indicate that CRC is mainly affected by environmental factors, eating habits, physical activity and genetic factors. As a newly recognized functional component, the intestinal microbiota plays important roles in preventing CRC formation and maintaining intestinal immunity. In this review, we summarize the mechanisms by which the gut microbiota causes CRC through alterations to immune function, focusing on the mechanisms by which intestinal microbial dysfunction promotes CRC. Furthermore, we describe the changes in the intestinal flora observed in CRC and their potential for CRC treatment with the goal of facilitating future research on the roles of the intestinal flora.

PIK3CA mutation and clinicopathological features of colorectal cancer: a systematic review and Meta-Analysis

Background: There is conflicting evidence regarding the association between PIK3CA mutations and clinicopathological features of colorectal cancer (CRC). We performed a comprehensive meta-analysis investigating the association between PIK3CA mutations and clinicopathological features in CRC, including subgroup analysis of mutations in exons 9 and 20, to elucidate the role of PIK3CA mutations in CRC.Materials and Methods: A detailed literature search was performed within the PubMed, Web of Science, and Embase databases, examining the associations between PIK3CA mutations and demographic characteristics, clinicopathologic parameters, and molecular features in patients with CRC. The odds ratios with 95% confidence intervals were used to estimate the effect of PIK3CA mutations on outcome parameters.Results: Forty-four studies enrolling 17621 patients were eligible for inclusion. PIK3CA mutations were associated with proximal tumor location, mucinous differentiation, KRAS mutations, and microsatellite instability (MSI). Subgroup analysis demonstrated that PIK3CA exon 9 mutations were positively associated with proximal tumor location and KRAS mutations, and negatively associated with BRAF mutations and MSI; exon 20 mutations were associated with proximal tumor location, KRAS mutations, BRAF mutations and MSI.Conclusions: Our findings suggest that overall or exon-specific PIK3CA mutations showed null associations with key clinicopathological parameters, including disease stage and tumor differentiation, indicating that PIK3CA mutations do not predict aggressive clinicopathological characteristics in CRC. As PIK3CA mutations were found to be closely associated with KRAS mutations, their relationship warrants further investigation. Since PIK3CA exon 9 and 20 mutations showed different tendencies with regard to BRAF mutation and MSI status, they may have distinct molecular impacts on CRC.

BMP9 mediates the anticancer activity of evodiamine through HIF‑1α/p53 in human colon cancer cells

Colon cancer is one of the most common malignancies. Although there has been great development in treatment regimens over the last few decades, its prognosis remains poor. There is still a clinical need to find new drugs for colon cancer. Evodiamine (Evo) is a quinolone alkaloid extracted from the traditional herbal medicine plant Evodia rutaecarpa. In the present study, CCK-8, flow cytometry, reverse transcription quantitative polymerase chain reaction, western blot analysis and a xenograft tumor model were used to evaluate the anti-cancer activity of Evo in human colon cancer cells and determine the possible mechanism underlying this process. It was revealed that Evo exhibited prominent anti-proliferation and apoptosis-inducing effects in HCT116 cells. Bone morphogenetic protein 9 (BMP9) was notably upregulated by Evo in HCT116 cells. Exogenous BMP9 potentiated the anti-cancer activity of Evo, and BMP9 silencing reduced this effect. In addition, HIF-1α was also upregulated by Evo. The anticancer activity of Evo was enhanced by HIF-1α, but was reduced by HIF-1α silencing. BMP9 potentiated the effect of Evo on the upregulation of HIF-1α, and enhanced the antitumor effect of Evo in colon cancer, which was clearly reduced by HIF-1α silencing. In HCT116 cells, Evo increased the phosphorylation of p53, which was enhanced by BMP9 but reduced by BMP9 silencing. Furthermore, the effect of Evo on p53 was potentiated by HIF-1α and reduced by HIF-1α silencing. The present findings therefore strongly indicated that the anticancer activity of Evo may be partly mediated by BMP9 upregulation, which can activate p53 through upregulation of HIF-1α, at least in human colon cancer.

Promising Therapeutic Efficacy of GC1118, an Anti-EGFR Antibody, against KRAS Mutation-Driven Colorectal Cancer Patient-Derived Xenografts

Epidermal growth factor receptor (EGFR)-targeted monoclonal antibodies, including cetuximab and panitumumab, are used to treat metastatic colorectal cancer (mCRC). However, this treatment is only effective for a small subset of mCRC patients positive for the wild-type KRAS GTPase. GC1118 is a novel, fully humanized anti-EGFR IgG1 antibody that displays potent inhibitory effects on high-affinity EGFR ligand-induced signaling and enhanced antibody-mediated cytotoxicity. In this study, using 51 CRC patient-derived xenografts (PDXs), we showed that KRAS mutants expressed remarkably elevated autocrine levels of high-affinity EGFR ligands compared with wild-type KRAS. In three KRAS-mutant CRCPDXs, GC1118 was more effective than cetuximab, whereas the two agents demonstrated comparable efficacy against three wild-type KRAS PDXs. Persistent phosphatidylinositol-3-kinase (PI3K)/AKT signaling was thought to underlie resistance to GC1118. In support of these findings, a preliminary improved anti-cancer response was observed in a CRC PDX harboring mutated KRAS with intrinsically high AKT activity using GC1118 combined with the dual PI3K/mammalian target of rapamycin (mTOR)/AKT inhibitor BEZ-235, without observed toxicity. Taken together, the superior antitumor efficacy of GC1118 alone or in combination with PI3K/mTOR/AKT inhibitors shows great therapeutic potential for the treatment of KRAS-mutant mCRC with elevated ratios of high- to low-affinity EGFR ligands and PI3K-AKT pathway activation.

Hypermethylation Of ADHFE1 Promotes The Proliferation Of Colorectal Cancer Cell Via Modulating Cell Cycle Progression

Background

Colorectal cancer (CRC) is one of the most common malignancies worldwide. Studies have demonstrated that epigenetic modifications play essential roles in the development of CRC. ADHFE1 is a differentially expressed gene that has been reported to be hypermethylated in CRC. However, the role and mechanism of ADHFE1 in the proliferation of CRC remain unclear.

Materials and methods

ADHFE1 expression was analyzed in CRC tissues by IHC and qRT-PCR, and the relationship between ADHFE1 expression and the clinicopathological parameters was analyzed. Cell proliferation were assessed by the in vitro and in vivo experimental models. GSEA assay was performed to explore the mechanism of ADHFE1 in the proliferation of CRC. Flow cytometry and Western blot were used to detect the activation of the cell cycle signaling. Bisulfite genomic sequence (BSP) assay was used to test the methylation degree of ADHFE1 gene promoter in CRC tissues.

Results

Here, we verified that ADHFE1 was down-regulated and hypermethylated in CRC tissues. The down-regulation of ADHFE1 was correlated with poor differentiation and advanced TNM stage of CRC patients. And ADHFE1 expression restored when the CRC cell line SW620 was treated with the demethylating agent 5-Aza-CdR. Overexpression of ADHFE1 inhibited the proliferation of CRC, while ADHFE1 knockdown promoted the proliferation of CRC cells in vitro and in vivo. Moreover, ADHFE1 overexpression could induce a significant G1-S cell cycle arrest in CRC cells and vice versa.

Conclusion

Hypermethylation of ADHFE1 might promote cell proliferation by modulating cell cycle progression in CRC, potentially providing a new therapeutic target for CRC patients.

Precision medicine for metastatic colorectal cancer: an evolving era

Introduction: Metastatic colorectal cancer (CRC) remains a dilemma for cancer researchers with an increasing incidence in the younger patient population. Until the last decade, limited therapeutic options were available for metastatic CRC patients leading to relatively poor clinical outcomes.Areas covered: With advances in genome sequencing technology and reductions in the cost of next-generation sequencing, molecular profiling has become more accessible for cancer researchers and clinical investigators, which has furthered our understanding of the molecular behavior of CRC. This progress has recently translated into significant advances in molecular-based therapeutics and led to the development of new target-specific agents in metastatic CRC patients. In this review article, we extensively elaborate on genomic alterations seen in CRC patients including, but not limited to, EGFR, MMR, BRAF, HER2, NTRKs, FGFR, BRCA1/2, PALB2, POLE, and POLD1 genes, all of which are potentially actionable by either an FDA-approved agent or in a clinical trial setting.Expert opinion: We strongly recommend molecular profiling in metastatic CRC patients during the early course of their disease, as this may provide therapeutic and prognostic information that can guide clinicians to practice precision medicine. Patients with potentially actionable genes should be considered for targeting agents based on molecular alterations.

Two Isoforms of the Guanine Nucleotide Exchange Factor, Daple/CCDC88C Cooperate as Tumor Suppressors

Previously, Aznar et al., showed that Daple/CCDC88C enables Wnt receptors to transactivate trimeric G-proteins during non-canonical Wnt signaling via a novel G-protein binding and activating (GBA) motif. By doing so, Daple serves two opposing roles; earlier during oncogenesis it suppresses neoplastic transformation and tumor growth, but later it triggers epithelial-to-mesenchymal-transition (EMT). We have identified and characterized two isoforms of the human Daple gene. While both isoforms cooperatively suppress tumor growth via their GBA motif, only the full-length transcript triggers EMT and invasion. Both isoforms are suppressed during colon cancer progression, and their reduced expression carries additive prognostic significance. These findings provide insights into the opposing roles of Daple during cancer progression and define the G-protein regulatory GBA motif as one of the minimal modules essential for Daple’s role as a tumor suppressor.

Metastatic Colorectal Cancer: Prognostic and Predictive Factors

Colorectal cancer represents the third most frequently occurring cancer worldwide. In the last decade, the survival of patients affected by metastatic colorectal cancer (mCRC) has improved through the introduction of biological drugs. However, in this new and dynamic therapeutic context, research about prognostic and predictive factors is important to guide the oncologists to effective therapies as well as to improve the understanding of colorectal cancer biology. Their identification is an intensive area of research and our future goal will be to depict tumour-specific "molecular signatures" in order to predict the clinical course of the disease and the best treatments. In this report, we describe clinical, pathological and molecular biomarkers that can play a role as prognostic or predictive factors in mCRC.

Driver genes exome sequencing reveals distinct variants in African Americans with colorectal neoplasia

BACKGROUND

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the United States. African Americans are disproportionately affected by CRC. Our hypothesis is that driver genes with known and novel mutations have an impact on CRC outcome in this population. Therefore, we investigated the variants' profiles in a panel of 15 CRC genes.

PATIENTS & METHODS

Colorectal specimens (n=140) were analyzed by targeted exome sequencing using an Ion Torrent platform. Detected variants were validated in 36 samples by Illumina sequencing. The novel status of the validated variants was determined by comparison to publicly available databases. Annotated using ANNOVAR and in-silico functional analysis of these variants were performed to determine likely pathogenic variants.

RESULTS

Overall, 121 known and novel variants were validated: APC (27%), AMER1 (3%), ARID1 (7%), MSH3 (12%), MSH6 (10%), BRAF (4%), KRAS (6%), FBXW7 (4%), PIK3CA (6%), SMAD4 (5%), SOX9 (2%), TCF7L2 (2%), TGFBR2 (5%), TP53 (7%). From these validated variants, 12% were novel in 8 genes (AMER1, APC, ARID1A, BRAF, MSH6, PIK3CA, SMAD4, and TCF7L2). Of the validated variants, 23% were non-synonymous, 14% were stopgains, 24% were synonymous and 39% were intronic variants.

CONCLUSION

We here report the specifics of variants' profiles of African Americans with colorectal lesions. Validated variants showed that Tumor Suppressor Genes (TSGs) APC and ARID1 and DNA Mismatch repair (MMR) genes MSH3 and MSH6 are the genes with the highest numbers of validated variants. Oncogenes KRAS and PIK3CA are also altered and likely participate in the increased proliferative potential of the mutated colonic epithelial cells in this population.

Approaches to functionally validate candidate genetic variants involved in colorectal cancer predisposition

Most next generation sequencing (NGS) studies identified candidate genetic variants predisposing to colorectal cancer (CRC) but do not tackle its functional interpretation to unequivocally recognize a new hereditary CRC gene. Besides, germline variants in already established hereditary CRC-predisposing genes or somatic variants share the same need when trying to categorize those with relevant significance. Functional genomics approaches have an important role in identifying the causal links between genetic architecture and phenotypes, in order to decipher cellular function in health and disease. Therefore, functional interpretation of identified genetic variants by NGS platforms is now essential. Available approaches nowadays include bioinformatics, cell and molecular biology and animal models. Recent advances, such as the CRISPR-Cas9, ZFN and TALEN systems, have been already used as a powerful tool with this objective. However, the use of cell lines is of limited value due to the CRC heterogeneity and its close interaction with microenvironment. Access to tridimensional cultures or organoids and xenograft models that mimic the in vivo tissue architecture could revolutionize functional analysis. This review will focus on the application of state-of-the-art functional studies to better tackle new genes involved in germline predisposition to this neoplasm.

Integration of microbiology, molecular pathology, and epidemiology: a new paradigm to explore the pathogenesis of microbiome-driven neoplasms

Molecular pathological epidemiology (MPE) is an integrative transdisciplinary field that addresses heterogeneous effects of exogenous and endogenous factors (collectively termed 'exposures'), including microorganisms, on disease occurrence and consequences, utilising molecular pathological signatures of the disease. In parallel with the paradigm of precision medicine, findings from MPE research can provide aetiological insights into tailored strategies of disease prevention and treatment. Due to the availability of molecular pathological tests on tumours, the MPE approach has been utilised predominantly in research on cancers including breast, lung, prostate, and colorectal carcinomas. Mounting evidence indicates that the microbiome (inclusive of viruses, bacteria, fungi, and parasites) plays an important role in a variety of human diseases including neoplasms. An alteration of the microbiome may be not only a cause of neoplasia but also an informative biomarker that indicates or mediates the association of an epidemiological exposure with health conditions and outcomes. To adequately educate and train investigators in this emerging area, we herein propose the integration of microbiology into the MPE model (termed 'microbiology-MPE'), which could improve our understanding of the complex interactions of environment, tumour cells, the immune system, and microbes in the tumour microenvironment during the carcinogenic process. Using this approach, we can examine how lifestyle factors, dietary patterns, medications, environmental exposures, and germline genetics influence cancer development and progression through impacting the microbial communities in the human body. Further integration of other disciplines (e.g. pharmacology, immunology, nutrition) into microbiology-MPE would expand this developing research frontier. With the advent of high-throughput next-generation sequencing technologies, researchers now have increasing access to large-scale metagenomics as well as other omics data (e.g. genomics, epigenomics, proteomics, and metabolomics) in population-based research. The integrative field of microbiology-MPE will open new opportunities for personalised medicine and public health. Copyright © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

FOLFOXIRI plus biologics in advanced colorectal cancer

INTRODUCTION

The combination of oxaliplatin, irinotecan, fluorouracil (5-FU), and leucovorin (FOLFOXIRI) results in improved outcomes compared with standard chemotherapy when used in frontline to treat patients with metastatic colorectal cancer (mCRC). FOLFOXIRI has been recently combined with biologic agents aiming further improvement in outcomes.

AREAS COVERED

This manuscript provides a comprehensive review of the results achieved by the FOLFOXIRI+biologic combination when used as first-line treatment in patients with mCRC. The search retrieved 19 clinical trial reports and 7 ongoing trials. The results are discussed focusing on secondary resection of metastatic disease, impact of sidedness (right-left primary tumor site), and impact of biomarkers.

EXPERT OPINION

Panitumumab is the only biologic that has proved its value when added to FOLFOXIRI in a randomized clinical trial. FOLFOXIRI-bevacizumab has the widest data from two large randomized phase III trials, being an option to be used in both the palliative and the conversion-therapy settings. However, the true benefit from adding bevacizumab remains to be established as it has not been evaluated in a randomized setting yet. Data on response rates and secondary resection rates are promising with the FOLFOXIRI-anti-EGFR combinations and may constitute a valuable option. Results of ongoing head-to-head studies will shed additional light on this issue.

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.

Prevalence and prognostic role of PIK3CA E545K mutation in Iranian colorectal cancer patients

AIM

This study aimed to evaluate the distribution of PIK3CA E545K mutation in Iranian CRC patients and explored its roles in disease prognosis.

BACKGROUND

Deregulation of the phosphoinositide 3-kinase (PI3K) pathway contributes to the progression of tumors. The p110a (PIK3CA), a catalytic subunit of PIK3, is mutated in many types of cancers. Exon 9 (E545K) is the most frequently mutated hotspot in PIK3CA in colorectal cancer (CRC). However, the prognostic role of PIK3CA E545K mutation needs to be elucidated.

METHODS

Tumors from 187 CRC patients were retrospectively collected from the Taleghani and Shohada Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran, between 2010 and 2017. PIK3CA E545K status was detected in Formalin-fixed paraffin-embedded (FFPE) tissues using PCR-RFLP methods, and validated by pyrosequencing. Correlations between PIK3CA E545K mutation clinicopathological features were analyzed.

RESULTS

The frequency of PIK3CA E545K gene mutations in CRC patients was 10.7%. Significant correlations were observed in PIK3CA E545K mutation with tumor differentiation and TNM stage (p < 0.042 and p = 0.033, respectively). Kaplan-Meier analysis showed a worse prognosis in overall survival (OS) in patients with PIK3CA E545K mutation (p < 0.001). Multivariate analysis indicated that PIK3CA E545K mutation was a detrimental factor for OS (HR = 6.497, 95% CI: 2.859-14.768, p < 0.021).

CONCLUSION

A high frequency of PIK3CA E545K mutation was detected in Iranian CRC patients. The results of the present study suggested that PIK3CA E545K mutation may be associated with poor prognosis. These findings require further confirmation via prospective studies with larger samples.

Tumor-preventing activity of aspirin in multiple cancers based on bioinformatic analyses

Background

Acetylsalicylic acid was renamed aspirin in 1899, and it has been widely used for its multiple biological actions. Because of the diversity of the cellular processes and diseases that aspirin reportedly affects and benefits, uncertainty remains regarding its mechanism in different biological systems.

Methods

The Drugbank and STITCH databases were used to find direct protein targets (DPTs) of aspirin. The Mentha database was used to analyze protein-protein interactions (PPIs) to find DPT-associated genes. DAVID was used for the GO and KEGG enrichment analyses. The cBio Cancer Genomics Portal database was used to mine genetic alterations and networks of aspirin-associated genes in cancer.

Results

Eighteen direct protein targets (DPT) and 961 DPT-associated genes were identified for aspirin. This enrichment analysis resulted in eight identified KEGG pathways that were associated with cancers. Analysis using the cBio portal indicated that aspirin might have effects on multiple tumor suppressors, such as TP53, PTEN, and RB1 and that TP53 might play a central role in aspirin-associated genes.

Discussion

The results not only suggest that aspirin might have anti-tumor actions against multiple cancers but could also provide new directions for further research on aspirin using a bioinformatics analysis approach.

MiR-384 inhibits the proliferation of colorectal cancer by targeting AKT3

Background

Growing evidence suggests that MiRNAs play essential roles in the initiation and progression of colorectal cancer (CRC). The aberrant expression of miR-384 has been reported in some cancers. However, the role and mechanism of miR-384 in CRC proliferation remains unknown.

Methods

The expression of miR-384 was detected in CRC and their paired normal tissues by real-time PCR. In vivo and in vitro assays were conducted to confirm the role of miR-384 in the proliferation of CRC. Bioinformatics analysis, luciferase reporter assays, western blot and in vitro assays were used to confirm that AKT3 was the target gene of miR-384. Finally, Spearman’s correlation analyses was carried out to analyze the relationship between miR-384 expression and AKT3 expression in CRC.

Results

MiR-384 was down‑regulated in CRC tissues. The in vivo and vitro functional assays verified that the ectopic upregulation of miR-384 inhibited the proliferation of CRC and the inhibition of miR-384 promoted the proliferation of CRC. Bioinformatics analysis, luciferase reporter assays, western blot and in vitro functional assays confirmed AKT3 as the target gene of miR-384. The expression of miR-384 was negatively correlated with the expressions of AKT3.

Conclusion

Our study verified that miR-384 could significantly suppress the proliferation of CRC by directing targeting AKT3.

Electronic supplementary material

The online version of this article (10.1186/s12935-018-0628-6) contains supplementary material, which is available to authorized users.

Integrative analysis of exogenous, endogenous, tumour and immune factors for precision medicine

Immunotherapy strategies targeting immune checkpoints such as the CTLA4 and CD274 (programmed cell death 1 ligand 1, PD-L1)/PDCD1 (programmed cell death 1, PD-1) T-cell coreceptor pathways are revolutionising oncology. The approval of pembrolizumab use for solid tumours with high-level microsatellite instability or mismatch repair deficiency by the US Food and Drug Administration highlights promise of precision immuno-oncology. However, despite evidence indicating influences of exogenous and endogenous factors such as diet, nutrients, alcohol, smoking, obesity, lifestyle, environmental exposures and microbiome on tumour-immune interactions, integrative analyses of those factors and immunity lag behind. Immune cell analyses in the tumour microenvironment have not adequately been integrated into large-scale studies. Addressing this gap, the transdisciplinary field of molecular pathological epidemiology (MPE) offers research frameworks to integrate tumour immunology into population health sciences, and link the exposures and germline genetics (eg, HLA genotypes) to tumour and immune characteristics. Multilevel research using bioinformatics, in vivo pathology and omics (genomics, epigenomics, transcriptomics, proteomics and metabolomics) technologies is possible with use of tissue, peripheral blood circulating cells, cell-free plasma, stool, sputum, urine and other body fluids. This immunology-MPE model can synergise with experimental immunology, microbiology and systems biology. GI neoplasms represent exemplary diseases for the immunology-MPE model, given rich microbiota and immune tissues of intestines, and the well-established carcinogenic role of intestinal inflammation. Proof-of-principle studies on colorectal cancer provided insights into immunomodulating effects of aspirin, vitamin D, inflammatory diets and omega-3 polyunsaturated fatty acids. The integrated immunology-MPE model can contribute to better understanding of environment-tumour-immune interactions, and effective immunoprevention and immunotherapy strategies for precision medicine.

Mutational burden, immune checkpoint expression, and mismatch repair in glioma: implications for immune checkpoint immunotherapy

Background

Despite a multiplicity of clinical trials testing immune checkpoint inhibitors, the frequency of expression of potential predictive biomarkers is unknown in glioma.

Methods

In this study, we profiled the frequency of shared biomarker phenotypes. To clarify the relationships among tumor mutational load (TML), mismatch repair (MMR), and immune checkpoint expression, we profiled patients with glioma (n = 327), including glioblastoma (GBM) (n = 198), whose samples had been submitted for analysis from 2009 to 2016. The calculation algorithm for TML included nonsynonymous mutation counts per tumor, with germline mutations filtered out. Immunohistochemical analysis and next-generation sequencing were used to determine tumor-infiltrating lymphocyte expression positive for programmed cell death protein 1 (PD-1), PD ligand 1 (PD-L1) expression on tumor cells, MMR (MLH1, MSH2, MSH6, and PMS2) protein expression and mutations, and DNA polymerase epsilon (POLE) mutations.

Results

High TML was only found in 3.5% of GBM patients (7 of 198) and was associated with the absence of protein expression of mutL homolog 1 (MLH1) (P = .0345), mutS homolog 2 (MSH2) (P = .0099), MSH6 (P = .0022), and postmeiotic segregation increased 2 (PMS2) (P = .0345) and the presence of DNA MMR mutations. High and moderate TML GBMs did not have an enriched influx of CD8+ T cells, PD-1+ T cells, or tumor-expressed PD-L1. IDH1 mutant gliomas were not enriched for high TML, PD-1+ T cells, or PD-L1 expression.

Conclusions

To clarify the relationships among TML, MMR, and immune checkpoint expression, we profiled the frequency of shared biomarker phenotypes. On the basis of a variety of potential biomarkers of response to immune checkpoints, only small subsets of glioma patients are likely to benefit from monotherapy immune checkpoint inhibition.

Association of FGFR2 and PI3KCA genetic variants with the risk of breast cancer in a Chinese population

Purpose

Genome-wide association studies have found plenty of single nucleotide polymorphisms (SNPs) which are associated with breast cancer risk. SNPs in FGFR2 are mostly identified. However, the association between PI3KCA SNP and breast cancer risk remains largely unknown. The aim of this study was to investigate the significance of FGFR2 and PI3KCA genetic variants in breast cancer and their association with prognosis.

Methods

We performed genotyping of 328 breast cancer patients and 389 healthy controls. Then, we evaluated the associations of FGFR2 rs1219648 and PI3KCA rs6443624 with the susceptibility and clinicopathological features of breast cancer. Kaplan-Meier curve with log-rank test was performed to determine the prognostic values of FGFR2 rs1219648 and PI3KCA rs6443624.

Results

The results indicated that genotype frequencies of rs1219648 and rs6443624 were significantly different between breast cancer patients and healthy controls. Furthermore, PI3KCA rs6443624 A carriers and FGFR2 rs1219648 G carriers more frequently had advanced stages and shorter survival times.

Conclusion

The SNPs of FGFR2 rs1219648 and PI3KCA rs6443624 may contribute to the identification of breast cancer patients at risk of more aggressive disease and may be potential prognostic factors in breast cancer in a Chinese population.

Human Gut Microbiota and Gastrointestinal Cancer

Human gut microbiota play an essential role in both healthy and diseased states of humans. In the past decade, the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities, as well as the possible mechanisms through which the microbiota are involved in cancer prevention, carcinogenesis, and anti-cancer therapy. A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways. Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing inflammation and immune dysregulation, which lead to genetic instability, but also interfere with the pharmacodynamics of anticancer agents. In this article, we mainly reviewed the influence of gut microbiota on cancers in the gastrointestinal (GI) tract (including esophageal, gastric, colorectal, liver, and pancreatic cancers) and the regulation of microbiota by diet, prebiotics, probiotics, synbiotics, antibiotics, or the Traditional Chinese Medicine. We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future. We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers, which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, diagnosis, and treatment.

MiR-384 inhibits human colorectal cancer metastasis by targeting KRAS and CDC42

Colorectal cancer (CRC) is the third most common cancer worldwide. Metastatic progression is a primary factor contributing to lethality of CRC patients. However, the molecular mechanisms forming early local invasion and distant metastatic colonies are still unclear and the present therapeutic approaches for CRC are unsatisfactory. Therefore, novel therapies targeting metastatic invasion that could prevent tumor spreading and recurrence are urgently needed. Our study showed that the decrease of miR-384 was found in 83.0% (83/100) CRC patients. And low-leveled expression of miR-384 was closely correlated with the invasive depth, lymph node and distant metastasis of CRC. Overexpression of miR-384 could inhibit the invasive and migrating abilities of CRC cells in vitro and the metastatic potential in vivo. Luciferase assays showed that miR-384 repressed the expression of Kirsten Ras (KRAS) and Cell division cycle 42 (CDC42) by directly targeting their 3’-untranslated regions. There is functional and mechanistic relationship between miRNA-384 and KRAS, CDC42 in the invasion and metastasis of CRC. And our findings suggest that miR-384could be a potent therapeutic target for CRC. Restoration of miR-384 expression might provide novel therapeutic approach to the reduction of CRC metastasis.

Kinase-targeted cancer therapies: progress, challenges and future directions

The human genome encodes 538 protein kinases that transfer a γ-phosphate group from ATP to serine, threonine, or tyrosine residues. Many of these kinases are associated with human cancer initiation and progression. The recent development of small-molecule kinase inhibitors for the treatment of diverse types of cancer has proven successful in clinical therapy. Significantly, protein kinases are the second most targeted group of drug targets, after the G-protein-coupled receptors. Since the development of the first protein kinase inhibitor, in the early 1980s, 37 kinase inhibitors have received FDA approval for treatment of malignancies such as breast and lung cancer. Furthermore, about 150 kinase-targeted drugs are in clinical phase trials, and many kinase-specific inhibitors are in the preclinical stage of drug development. Nevertheless, many factors confound the clinical efficacy of these molecules. Specific tumor genetics, tumor microenvironment, drug resistance, and pharmacogenomics determine how useful a compound will be in the treatment of a given cancer. This review provides an overview of kinase-targeted drug discovery and development in relation to oncology and highlights the challenges and future potential for kinase-targeted cancer therapies.

Surface Enhanced Raman Spectroscopy (SERS) for the Multiplex Detection of Braf, Kras, and Pik3ca Mutations in Plasma of Colorectal Cancer Patients

In this paper, we discuss the use of a procedure based on polymerase chain reaction (PCR) and surface enhanced Raman spectroscopy (SERS) (PCR-SERS) to detect DNA mutations.

Methods: This method was implemented by first amplifying DNA-containing target mutations, then by annealing probes, and finally by applying SERS detection. The obtained SERS spectra were from a mixture of fluorescence tags labeled to complementary sequences on the mutant DNA. Then, the SERS spectra of multiple tags were decomposed to component tag spectra by multiple linear regression (MLR).

Results: The detection limit was 10^-11 M with a coefficient of determination (R²) of 0.88. To demonstrate the applicability of this process on real samples, the PCR-SERS method was applied on blood plasma taken from 49 colorectal cancer patients to detect six mutations located at the BRAF, KRAS, and PIK3CA genes. The mutation rates obtained by the PCR-SERS method were in concordance with previous research. Fisher's exact test showed that only two detected mutations at BRAF (V600E) and PIK3CA (E542K) were significantly positively correlated with right-sided colon cancer. No other clinical feature such as gender, age, cancer stage, or differentiation was correlated with mutation (V600E at BRAF, G12C, G12D, G12V, G13D at KRAS, and E542K at PIK3CA). Visually, a dendrogram drawn through hierarchical clustering analysis (HCA) supported the results of Fisher's exact test. The clusters drawn by all six mutations did not conform to the distributions of cancer stages, differentiation or cancer positions. However, the cluster drawn by the two mutations of V600E and E542K showed that all samples with those mutations belonged to the right-sided colon cancer group.

Conclusion: The suggested PCR-SERS method is multiplexed, flexible in probe design, easy to incorporate into existing PCR conditions, and was sensitive enough to detect mutations in blood plasma.

Human Gut Microbiota and Gastrointestinal Cancer

Human gut microbiota play an essential role in both healthy and diseased states of humans. In the past decade, the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities, as well as the possible mechanisms through which the microbiota are involved in cancer prevention, carcinogenesis, and anti-cancer therapy. A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways. Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing inflammation and immune dysregulation, which lead to genetic instability, but also interfere with the pharmacodynamics of anticancer agents. In this article, we mainly reviewed the influence of gut microbiota on cancers in the gastrointestinal (GI) tract (including esophageal, gastric, colorectal, liver, and pancreatic cancers) and the regulation of microbiota by diet, prebiotics, probiotics, synbiotics, antibiotics, or the Traditional Chinese Medicine. We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future. We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers, which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, diagnosis, and treatment.

Review Article: The Role of Molecular Pathological Epidemiology in the Study of Neoplastic and Non-neoplastic Diseases in the Era of Precision Medicine

Molecular pathology diagnostics to subclassify diseases based on pathogenesis are increasingly common in clinical translational medicine. Molecular pathological epidemiology (MPE) is an integrative transdisciplinary science based on the unique disease principle and the disease continuum theory. While it has been most commonly applied to research on breast, lung, and colorectal cancers, MPE can investigate etiologic heterogeneity in non-neoplastic diseases, such as cardiovascular diseases, obesity, diabetes mellitus, drug toxicity, and immunity-related and infectious diseases. This science can enhance causal inference by linking putative etiologic factors to specific molecular biomarkers as outcomes. Technological advances increasingly enable analyses of various -omics, including genomics, epigenomics, transcriptomics, proteomics, metabolomics, metagenomics, microbiome, immunomics, interactomics, etc. Challenges in MPE include sample size limitations (depending on availability of biospecimens or biomedical/radiological imaging), need for rigorous validation of molecular assays and study findings, and paucities of interdisciplinary experts, education programs, international forums, and standardized guidelines. To address these challenges, there are ongoing efforts such as multidisciplinary consortium pooling projects, the International Molecular Pathological Epidemiology Meeting Series, and the Strengthening the Reporting of Observational Studies in Epidemiology-MPE guideline project. Efforts should be made to build biorepository and biobank networks, and worldwide population-based MPE databases. These activities match with the purposes of the Big Data to Knowledge (BD2K), Genetic Associations and Mechanisms in Oncology (GAME-ON), and Precision Medicine Initiatives of the United States National Institute of Health. Given advances in biotechnology, bioinformatics, and computational/systems biology, there are wide open opportunities in MPE to contribute to public health.

Mutations of KRAS, NRAS, BRAF, EGFR, and PIK3CA genes in urachal carcinoma: Occurence and prognostic significance

Purpose

Targeted therapy represents an attractive alternative for rare tumors such as urachal carcinoma (UrC). The aim of this study was to assess the mutations of the most commonly affected 5 genes in the targetable EGFR-pathway in UrC and comapre their frequencies to those of found in urothelial and colorectal cancer.

Materials and Methods

Mutational hot-spots of selected genes were tested in 22 UrC samples by pyrosequencing. Mutational patterns were compared to those published for colorectal and urothelial cancers. Furthermore, we sought correlations between mutations and clinicopathological and follow-up data.

Results

We found 11 mutations in 10 of 22 (45%) patients. The most frequently mutated gene was KRAS (27%) followed by BRAF (18%) and NRAS (5%), while no mutations were detected in the EGFR and PIK3CA genes. No correlation was found between the mutation status and clinicopathological parameters (Sheldon/Mayo stage, tumor grade, metastases). Furthermore, none of the mutations correlated with progression-free or overall survival.

Conclusions

The mutation pattern of UrC is more similar to colorectal than to urothelial cancer. However, the mutation characteristics of UrC seems to be unique suggesting that clinical decision-making for UrC cannot be simply adopted from urothelial or colorectal carcinoma. The high occurence of EGFR-pathway mutations warrants the testing for KRAS and BRAF mutations when considering anti-EGFR therapy in UrC.

Curcumol induces cell cycle arrest in colon cancer cells via reactive oxygen species and Akt/ GSK3β/cyclin D1 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Curcuma kwangsiensis S. G. Lee & C. F. Liang (Guangxi ezhu, in Chinese) belongs to the Zingiberaceae family, has been used as a traditionally Chinese medicine nearly 2000 year. Curcumol is one of the guaiane-type sesquiterpenoid hemiketal isolated from medicine plant Curcuma kwangsiensis S. G. Lee & C. F. Liang, which has been reported possesses anti-cancer effects. Our previous study found that the most contribution to inhibit nasopharyngeal carcinoma cell growth was curcumol.

AIM OF THE STUDY

To assess the effect of curcumol on cell cycle arrest against human colon cancer cells (CRC) cells (LoVo and SW480) and explore its mechanism in vitro and in vivo.

MATERIALS AND METHODS

Curcumol was dissolved in absolute ethyl alcohol. The concentration of absolute ethyl alcohol in the control group or in experimental samples was always 1/500 (v/v) of the final medium volume. LoVo and SW480 cells were treated with different concentrations of curcumol (0, 53, 106, 212 and 424μM). And then the cell cycle of each group was examined by flow cytometry. The protein levels of PI3K, p-Akt, cyclin D1, cyclin E, CDK2, CDK4 and GSK3β were determined by Western blot. The mRNA expression of PI3K, Akt, cyclin D1, CDK4, P27, p21, and P16 in the treated cells were analyzed by real-time RT-PCR. In addition, the antitumor activity of curcumol was evaluated in nude mice bearing orthotopic tumor implants.

RESULTS

Curcumol induced cell cycle arrest in G1/S phase. RT-qPCR and Western blot data showed that curcumol enhanced the expression of GSK3β, P27, p21 and P16, and decreased the levels of PI3K, phosphorylated Akt (p-Akt), cyclin D1, CDK4, cyclin E and CDK2. Furthermore, curcumol induced reactive oxygen species (ROS) generation in LoVo cells, and ROS scavenger N-acetylcysteine (NAC) significantly reversed curcumol-induced cell growth inhibition. Besides, curcumol also prevented the growth of human colon cancer cells xenografts in nude mouse, accompanied by the reduction of PI3K, Akt, cyclin D1, CDK4, cycln E and significant increase of GSK3β.

CONCLUSIONS

Curcumol caused cell cycle arrest at the G0/G1 phase by ROS production and Akt/ GSK3β/cyclin D1 pathways inactivation, indicating the potential of curcumol in the prevention of colon cancer carcinogenesis.

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.

The predictive value of primary tumor location in patients with metastatic colorectal cancer: A systematic review

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers worldwide. It has been reported that left- and right-sided CRC harbor varying disease characteristics, which leads to a difference in prognosis and response to therapy. Recently, there have been retrospective studies about tumor location in metastatic CRC (mCRC) and its potential to predict the effect of anti-vascular endothelial growth factor and anti-epidermal growth factor receptor (anti-EGFR) therapies. In this review, we provide a comprehensive overview of the latest trials studying the predictive value of primary tumor location in mCRC and discuss biomarkers that might be associated with the differences in treatment response. Although data need to be interpreted with caution due to the absence of randomized trials stratified based on tumor location, patients with left-sided CRC seem to benefit more from anti-EGFR therapy than patients with right-sided CRC. Further clinical trials, stratified for tumor location, are warranted.