Targeted therapy for metastatic colorectal cancer

A signature of circulating microRNAs predicts the response to treatment with FOLFIRI plus aflibercept in metastatic colorectal cancer patients

The benefit of adding the antiangiogenic drug aflibercept to FOLFIRI regime in metastatic colorectal cancer (CRC) patients resistant to or progressive on an oxaliplatin-based therapy has been previously demonstrated. However, the absence of validated biomarkers to predict greater outcomes is a major challenge encountered when using antiangiogenic therapies. In this study we investigated profiles of circulating microRNAs (miRNAs) to build predictive models of response to treatment and survival. Plasma was obtained from 98 metastatic CRC patients enrolled in a clinical phase II trial before receiving FOLFIRI plus aflibercept treatment, and the circulating levels of 754 individual miRNAs were quantified using real-time PCR. A distinct signature of circulating miRNAs differentiated responder from non-responder patients. Remarkably, most of these miRNAs were found to target genes that are involved in angiogenic processes. Accordingly, some of these miRNAs had predictive value and entered in predictive models of response to therapy, progression of disease, and survival of patients treated with FOLFIRI plus aflibercept. Among these miRNAs, circulating levels of hsa-miR-33b-5p efficiently discriminated between responder and non-responder patients and predicted the risk of disease progression. Moreover, the combination of circulating VEGF-A and miR-33b-5p levels improved clinical stratification of metastatic CRC patients who were to receive FOLFIRI plus aflibercept treatment. In conclusion, our study supports circulating miRNAs as valuable biomarkers for predicting better outcomes in metastatic CRC patients treated with FOLFIRI plus aflibercept.

Role of microRNA-34b-5p in cancer and injury: how does it work?

MicroRNAs (miRNAs or miRs) are a class of noncoding single-stranded RNAs that can regulate gene expression by binding to the untranslated sequences at the 3 ' end of messenger RNAs. The microRNA-34 family is dysregulated in various human diseases. It is considered as a tumor-suppressive microRNA because of its synergistic effect with the well-known tumor suppressor p53. As a member of the miRNA-34 family, miR-34b-5p serves as a powerful regulator of a suite of cellular activities, including cell growth, multiplication, development, differentiation, and apoptosis. It promotes or represses disease occurrence and progression by participating in some important signaling pathways. This review aimed to provide an overview and update on the differential expression and function of miR-34b-5p in pathophysiologic processes, especially cancer and injury. Additionally, miR-34b-5p-mediated clinical trials have indicated promising consequences for the therapies of carcinomatosis and injury. With the application of the first tumor-targeted microRNA drug based on miR-34a mimics, it can be inferred that miR-34b-5p may become a crucial factor in the therapy of various diseases. However, further studies on miR-34b-5p should shed light on its involvement in disease pathogenesis and treatment options.

CAR T-cells for colorectal cancer immunotherapy: Ready to go?

Chimeric antigen receptor (CAR) T-cells represent a new genetically engineered cell-based immunotherapy tool against cancer. The use of CAR T-cells has revolutionized the therapeutic approach for hematological malignancies. Unfortunately, there is a long way to go before this treatment can be developed for solid tumors, including colorectal cancer. CAR T-cell therapy for colorectal cancer is still in its early stages, and clinical data are scarce. Major limitations of this therapy include high toxicity, relapses, and an impermeable tumor microenvironment for CAR T-cell therapy in colorectal cancer. In this review, we summarize current knowledge, highlight challenges, and discuss perspectives regarding CAR T-cell therapy in colorectal cancer.

Downregulation of MiR-1538 promotes proliferation and metastasis of colorectal cancer by targeting DNMT3A

Colorectal cancer (CRC) is a common malignant tumor of digestive tract, but the molecular mechanism of its occurrence and development is not clear. Some studies have shown that microRNA (miRNA) plays an important role in the occurrence and development of cancer, but many miRNAs which play an important role in the progression of CRC remain to be investigated. In this study，we found that the expression of miR-1538 was significantly down-regulated in CRC tissues and cells, and its expression level was significantly correlated with tumor size, clinical stage and prognosis. Functional and mechanism experiments showed that miR-1538 decreased the protein level of DNA methyltransferases 3A (DNMT3A) and inhibited the proliferation, migration and invasion of CRC cells by targeting the 3'-UTR of DNMT3A mRNA. Our results identify the biological function and mechanism of miR-1538 as a tumor suppressor gene in the progression of CRC, and suggest that miR-1538 can be used as a potential prognostic marker and therapeutic target for CRC.

Genetic Characteristics of Resectable Colorectal Cancer with Pulmonary Metastasis

The lung is the most common extra-abdominal metastasis site of colorectal cancer (CRC). This study aimed to investigate the genetic variation of pulmonary metastases (PM) and primary tumors in resectable CRC. The clinical data of 410 patients with PM after CRC surgery and 33 paraffin-embedded tissue samples from January 2012 to July 2019 in our hospital were collected retrospectively. Next, 450-panel gene detection technologies based on next-generation sequencing (NGS) were used to analyze the changes in the gene map and the overall variation in cancer-related genes in PM and primary tumors. After quality control, 19 samples were included in the final gene analysis. The results showed that APC (89.5%), TP53 (89.5%), and KRAS (53%) were the most common mutations in PM and primary tumors, but the gene amplification variation was enriched in primary tumors (4.6% vs. 11.4%). KRAS G12D was the most common site variation of the KRAS gene in both PM and primary tumors of CRC. There was no hotspot mutation in the TP53 locus in CRC, and the TP53 mutation in the PM was consistent with that in the primary lesion. The microsatellite instability (MSI) levels of 10 patients were MSS. The mean tumor mutation burden (TMB) of the primary tumor (5.3 muts·Mb^-1) was slightly higher than that of metastasis (5.0 muts·Mb^-1). In our institution, the genetic characteristics of resectable PM from CRC may be highly consistent with those of the primary tumor.

Luteolin inhibits viability, migration, angiogenesis and invasion of non-small cell lung cancer vascular endothelial cells via miR-133a-3p/purine rich element binding protein B-mediated MAPK and PI3K/Akt signaling pathways

Luteolin inhibits tumorigenesis of non-small cell lung cancer (NSCLC), but its mechanism still needs to be clarified. We hereby explored the effects of luteolin in vascular endothelial cells of NSCLC (NSCLC-VECs). After extraction and identification of NSCLC-VECs, cells were treated with luteolin and transfected. The viability, migration, angiogenesis and invasion of the cells were measured. The levels of miR-133a-3p, purine rich element binding protein B (PURB), vascular endothelial growth factor (VEGF), phosphatidylinositol 3-kinase (PI3K), Akt, mitogen-activated protein kinases (MAPK), matrix metalloproteinase (MMP)-2/-9 were determined. The interaction relationship of miR-133a-3p and PURB was identified. Luteolin inhibited the viability, migration, angiogenesis and invasion of NSCLC-VECs yet up-regulated miR-133a-3p level, while miR-133a-3p inhibitor counteracted the repressive effect of luteolin on the viability, migration, angiogenesis, and invasion in NSCLC-VECs. Luteolin inhibited the expressions of migration- and invasion-associated proteins (VEGF, MMP-2 and MMP-9), PI3K/Akt and MAPK signaling pathways-related factors, while miR-133a-3p inhibitor reversed the inhibitory effect of Luteolin on NSCLC-VECs. Luteolin decreased the level of PURB, which was targeted by miR-133a-3p. ShPURB promoted miR-133a-3p level in NSCLC-VECs, while reversing the promoting effects of miR-133a-3p inhibitor on the migration, invasion, and levels of migration- and invasion-associated proteins, PI3K/Akt and MAPK pathways-associated factors in NSCLC-VECs. Collectively speaking, luteolin inhibits the migration and invasion of NSCLC-VECs via miR-133a-3p/PURB- mediated MAPK and PI3K/Akt pathways.

SOX8 promotes cetuximab resistance via HGF/MET bypass pathway activation in colorectal cancer

AIM

Cetuximab is an essential drug for the treatment of wild-type K-RAS colorectal cancer (CRC). It improves the overall survival of patients. However, acquired resistance prevents its clinical efficacy. Tumor heterogeneity may be a nonnegligible reason for cetuximab resistance. We attempted to explore the corresponding molecular mechanism.

METHODS

Cetuximab-resistant CRC cell RKO and cetuximab-sensitive CRC cell Caco-2 were applied in this study. Cells were centrifuged to determine the concentration in the culture supernatant (CS). MTT, EdU, and colony formation assays were utilized to evaluate cell survival and proliferation. Chromatin immunoprecipitation (ChIP) and promoter-luciferase reporter assays were employed to confirm the direct binding of transcription factors. Western blot and reverse transcription-polymerase chain reaction (RT-PCR) assays were used to detect the expression of molecular markers in the pathway.

RESULTS

Hepatocyte growth factor (HGF) was up-regulated in RKO cell culture supernatant and induced cetuximab resistance in Caco-2 cells. SRY-Box Transcription Factor 8 (SOX8) bound to the promoter sequence of HGF. HGF activated the HGF/MET bypass pathway and induced cetuximab resistance in Caco-2 cells.

CONCLUSION

The SOX8/HGF/MET axis played a crucial role in the communication between cetuximab-resistant cells and cetuximab-sensitive cells, inducing treatment resistance.

The Effect of Liposomal Diallyl Disulfide and Oxaliplatin on Proliferation of Colorectal Cancer Cells: In Vitro and In Silico Analysis

Diallyl disulfide (DADS) is one of the main bioactive organosulfur compounds of garlic, and its potential against various cancer models has been demonstrated. The poor solubility of DADS in aqueous solutions limits its uses in clinical application. The present study aimed to develop a novel formulation of DADS to increase its bioavailability and therapeutic potential and evaluate its role in combination with oxaliplatin (OXA) in the colorectal cancer system. We prepared and characterized PEGylated, DADS (DCPDD), and OXA (DCPDO) liposomes. The anticancer potential of these formulations was then evaluated in HCT116 and RKO colon cancer cells by different cellular assays. Further, a molecular docking-based computational analysis was conducted to determine the probable binding interactions of DADS and OXA. The results revealed the size of the DCPDD and DCPDO to be 114.46 nm (95% EE) and 149.45 nm (54% EE), respectively. They increased the sensitivity of the cells and reduced the IC₅₀ several folds, while the combinations of them showed a synergistic effect and induced apoptosis by 55% in the cells. The molecular docking data projected several possible targets of DADS and OXA that could be evaluated more precisely by these novel formulations in detail. This study will direct the usage of DCPDD to augment the therapeutic potential of DCPDO against colon cancer in clinical settings.

Downregulation of microRNA-6125 promotes colorectal cancer growth through YTHDF2-dependent recognition of N6-methyladenosine-modified GSK3β

BACKGROUND

MicroRNAs (miRNAs), the key regulator of gene expression, and N6-methyladenosine (m6A) RNA modification play a significant role in tumour progression. However, regulation of m6A-modified mRNAs by miRNAs in colorectal cancer (CRC), and its effect on progression of CRC, remains to be investigated.

METHODS

Expression of miR-6125 and YTH Domain-Containing Family Protein 2 (YTHDF2) was detected by western blotting and immunohistochemistry. The effects of miR-6125 and YTHDF2 on proliferative capacity of CRC cells were analysed using soft agar, ATP, CCK8 and EdU assays, and in animal experiments.

RESULTS

MiR-6125 expression was downregulated markedly in CRC, and expression correlated negatively with tumour size and prognosis. MiR-6125 targeted the 3'-UTR of YTHDF2 and downregulated the YTHDF2 protein, thereby increasing the stability of m6A-modified glycogen synthase kinase 3 beta (GSK3β) mRNA. Increased GSK3β protein levels inhibited the expression of Wnt/β-catenin/Cyclin D1 pathway-related proteins, leading to G0-G1 phase arrest and ultimately inhibiting the proliferation of CRC cells.

CONCLUSIONS

MiR-6125 regulates YTHDF2 and thus plays a critical role in regulating the Wnt/β-catenin pathway, thereby affecting the growth of CRC. Collectively, these results suggest that miR-6125 and YTHDF2 are potential targets for treatment of CRC.

CircRASSF2 facilitates the proliferation and metastasis of colorectal cancer by mediating the activity of Wnt/β-catenin signaling pathway by regulating the miR-195-5p/FZD4 axis

Circular RNAs (circRNA) are a key regulator of cancer progression, including colorectal cancer (CRC). Nevertheless, the role of circRASSF2 in CRC remains unclear. Quantitative real-time PCR was used to measure the expression of circRASSF2 and miR-195-5p. Cell counting kit 8 assay, colony formation assay, flow cytometry and transwell assay were used to determine the proliferation, apoptosis, migration and invasion of cells, respectively. The levels of proliferation, metastasis and Wnt/β-catenin signaling pathway-related proteins, as well as Frizzled 4 (FZD4) protein, were determined using western blot analysis. Furthermore, a dual-luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay were used to illumine the mechanism of circRASSF2. Animal experiments were used to determine the role of circRASSF2 in the tumor growth of CRC in vivo. Our study reported that circRASSF2 was upregulated in CRC tissues and cells, and its high expression was related to the poor prognosis of CRC patients. CircRASSF2 knockdown could inhibit proliferation, migration, invasion, and enhance apoptosis in CRC cells, and its overexpression had the opposite effect. Besides, our data revealed that circRASSF2 could sponge miR-195-5p, and miR-195-5p could target FZD4. The rescue experiments indicated that both miR-195-5p inhibitor and FZD4 overexpression could reverse the negative regulation of circRASSF2 silencing on CRC progression. Moreover, circRASSF2 could positively regulate the activity of Wnt/β-catenin signaling pathway by the miR-195-5p/FZD4 axis. In addition, circRASSF2 knockdown restrained the tumor growth of CRC in vivo. Our findings suggested that circRASSF2 might function as a tumor promoter to accelerate the progression of CRC via regulating the miR-195-5p/FZD4/Wnt/β-catenin pathway.

Growth Factors, PI3K/AKT/mTOR and MAPK Signaling Pathways in Colorectal Cancer Pathogenesis: Where Are We Now?

Colorectal cancer (CRC) is a predominant malignancy worldwide, being the fourth most common cause of mortality and morbidity. The CRC incidence in adolescents, young adults, and adult populations is increasing every year. In the pathogenesis of CRC, various factors are involved including diet, sedentary life, smoking, excessive alcohol consumption, obesity, gut microbiota, diabetes, and genetic mutations. The CRC tumor microenvironment (TME) involves the complex cooperation between tumoral cells with stroma, immune, and endothelial cells. Cytokines and several growth factors (GFs) will sustain CRC cell proliferation, survival, motility, and invasion. Epidermal growth factor receptor (EGFR), Insulin-like growth factor -1 receptor (IGF-1R), and Vascular Endothelial Growth Factor -A (VEGF-A) are overexpressed in various human cancers including CRC. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) and all the three major subfamilies of the mitogen-activated protein kinase (MAPK) signaling pathways may be activated by GFs and will further play key roles in CRC development. The main aim of this review is to present the CRC incidence, risk factors, pathogenesis, and the impact of GFs during its development. Moreover, the article describes the relationship between EGF, IGF, VEGF, GFs inhibitors, PI3K/AKT/mTOR-MAPK signaling pathways, and CRC.

CircFAM120B Blocks the Development of Colorectal Cancer by Activating TGF-Beta Receptor II Expression via Targeting miR-645

Circular RNAs (circRNAs) are implicated in various human cancers, including colorectal cancer (CRC). The objective of this study was to investigate the function and regulatory mechanism of a novel circRNA, circFAM120B, in CRC development. The expression of circFAM120B, miR-645 and TGF-beta receptor II (TGFBR2) mRNA was detected by quantitative real-time polymerase chain reaction. Cellular biological functions, including cell proliferation, migration/invasion, and glycolysis metabolism, were assessed using CCK-8 assay, colony formation assay, transwell assay, and glycolysis stress test, respectively. Glycolysis progression was also monitored by lactate production and glucose consumption. The expression of glycolysis-related markers and TGFBR2 at the protein level was detected by western blot. The interaction between miR-645 and circFAM120B or TGFBR2 was predicted by bioinformatics analysis and verified by pull-down assay, dual-luciferase reporter assay and RIP assay. In vivo animal experiments were performed to further explore the function of circFAM120B. The expression of circFAM120B was decreased in CRC tissues and cells. CircFAM120B overexpression blocked CRC cell proliferation, migration/invasion, and glycolysis metabolism. MiR-645 was a target of circFAM120B, and miR-645 restoration reversed the effects of circFAM120B overexpression. In addition, TGFBR2 was a target of miR-645, and miR-645 inhibition-suppressed CRC cell proliferation, migration/invasion and glycolysis were restored by TGFBR2 knockdown. Moreover, circFAM120B activated the expression of TGFBR2 by targeting miR-645. TGFBR2 also blocked tumor growth in vivo by targeting the miR-645/TGFBR2 axis. CircFAM120B inhibited CRC progression partly by mediating the miR-645/TGFBR2 network, which explained the potential mechanism of circFAM120B function in CRC.

MET overexpression and intratumor heterogeneity in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is among the ten most frequent and deadly cancers, without effective therapies for most patients. More recently, drugs targeting deregulated growth factor signaling receptors have been developed, such as HGF-MET targeted therapy. We assessed MET and HGF genetic alterations and gene and protein expression profiles in ESCC patients from the Brazilian National Cancer Institute and publicly available datasets, as well as the intratumor heterogeneity of the alterations found. Our analyses showed that HGF and MET genetic alterations, both copy number and mutations, are not common in ESCC, affecting 5 and 6% of the cases, respectively. HGF showed a variable mRNA expression profile between datasets, with no alterations (GSE20347), downregulation (GSE45670), and upregulation in ESCC (our dataset and GSE75241). On the other hand, MET was found consistently upregulated in ESCC compared to non-tumor surrounding tissue, with median fold-changes of 5.96 (GSE20347), 3.83 (GSE45670), 6.02 (GSE75241), and 5.0 (our dataset). Among our patients, 84% of the tumors showed at least a two-fold increase in MET expression. This observation was corroborated by protein levels, with 55% of cases exhibiting positivity in 100% of the tumor cells. Intratumor heterogeneity was evaluated in at least four tumor biopsies from five patients and two cases showed a consistent increase in MET expression (at least two-fold) in all tumor samples. Our data suggested that HGF-MET signaling pathway was likely to be overactivated in ESCC, representing a potential therapeutic target, but eligibility for this therapy should consider intratumor heterogeneity.

Efficacy and safety of chronomodulated irinotecan, oxaliplatin, 5-fluorouracil and leucovorin combination as first- or second-line treatment against metastatic colorectal cancer: Results from the International EORTC 05011 Trial

The triplet combination of irinotecan, oxaliplatin and fluorouracil is an active frontline regimen in metastatic colorectal cancer, but scarce data exist on its use as salvage treatment. We aimed at assessing its safety and efficacy profiles with its circadian-based administration (chronoIFLO5) as either first- or second-line treatment, within the time-finding EORTC 05011 trial. Five-day chronoIFLO5 was administered every 3 weeks in patients with PS 0, 1 or 2. It consisted of chronomodulated irinotecan (180 mg/sqm), oxaliplatin (80 mg/sqm) and fluorouracil-leucovorin (2800 and 1200 mg/sqm, respectively). For our study, toxicity and antitumour activity were evaluated separately in first- and second-line settings. Primary endpoints included Grade 3-4 toxicity rates, best objective response rate (ORR), progression-free survival (PFS) and overall survival (OS). One-hundred forty-nine and 44 patients were treated in first-line and second-line settings, respectively, with a total of 1138 cycles with median relative dose intensities of about 90%. Demographics were comparable in the two groups. Thirty-six (24.7%) and 10 (22.2%) patients experienced at least one episode of severe toxicity in first line and second line, respectively. Frontline chronoIFLO5 yielded an ORR of 62.3% [95% CI: 54.2-70.4] and resulted in median PFS and OS of 8.7 months [7.5-9.9] and 19.9 months [15.4-24.5]. Corresponding figures in second line were 37.5% [22.5-52.5], 6.7 months [4.8-8.9] and 16.3 months [11.8-20.8]. International and prospective evaluation revealed the favourable safety and efficacy profiles of chronoIFLO5, both as frontline and as salvage treatment against metastatic colorectal cancer. In particular, encouraging activity in second line was observed, with limited haematological toxicity.

SELE gene as a characteristic prognostic biomarker of colorectal cancer

OBJECTIVE

To investigate the expression and clinical value of the E-selectin gene (SELE) in colorectal cancer (CRC).

METHODS

Using gene expression profiles and clinicopathological data for patients with CRC from The Cancer Genome Atlas, and tumor and adjacent normal tissues from 31 patients with CRC from Xianyang Central Hospital, we studied the correlation between SELE gene expression and clinical parameters using Kaplan-Meier and Cox proportional hazards regression analyses.

RESULTS

Higher expression of SELE was significantly associated with a poorer prognosis and shorter survival in patients with CRC. The median expression level of SELE was significantly higher in CRC tissues compared with healthy adjacent tissue. Cox regression analysis showed that the prognosis of CRC was significantly correlated with the expression of SELE. Immunohistochemical analysis also showed that positive expression of E-selectin increased significantly in line with increasing TNM stage.Conclusion: This study confirmed that SELE gene expression is an independent prognostic factor in patients with CRC.

RGD4C peptide mediates anti-p21Ras scFv entry into tumor cells and produces an inhibitory effect on the human colon cancer cell line SW480

Background

We prepared an anti-p21Ras scFv which could specifically bind with mutant and wild-type p21Ras. However, it cannot penetrate the cell membrane, which prevents it from binding to p21Ras in the cytoplasm. Here, the RGD4C peptide was used to mediate the scFv penetration into tumor cells and produce antitumor effects.

Methods

RGD4C-EGFP and RGD4C-p21Ras-scFv recombinant expression plasmids were constructed to express fusion proteins in E. coli, then the fusion proteins were purified with HisPur Ni-NTA. RGD4C-EGFP was used as reporter to test the factors affecting RGD4C penetration into tumor cell. The immunoreactivity of RGD4C-p21Ras-scFv toward p21Ras was identified by ELISA and western blotting. The ability of RGD4C-p21Ras-scFv to penetrate SW480 cells and colocalization with Ras protein was detected by immunocytochemistry and immunofluorescence. The antitumor activity of the RGD4C-p21Ras-scFv was assessed with the MTT, TUNEL, colony formation and cell migration assays. Chloroquine (CQ) was used an endosomal escape enhancing agent to enhance endosomal escape of RGD4C-scFv.

Results

RGD4C-p21Ras-scFv fusion protein were successfully expressed and purified. We found that the RGD4C fusion protein could penetrate into tumor cells, but the tumor cell entry of was time and concentration dependent. Endocytosis inhibitors and a low temperature inhibited RGD4C fusion protein endocytosis into cells. The change of the cell membrane potential did not affect penetrability. RGD4C-p21Ras-scFv could penetrate SW480 cells, effectively inhibit the growth, proliferation and migration of SW480 cells and promote this cells apoptosis. In addition, chloroquine (CQ) could increase endosomal escape and improve antitumor activity of RGD4C-scFv in SW480 cells.

Conclusion

The RGD4C peptide can mediate anti-p21Ras scFv entry into SW480 cells and produce an inhibitory effect, which indicates that RGD4C-p21Ras-scFv may be a potential therapeutic antibody for the treatment of ras-driven cancers.

High-dose administration of tyrosine kinase inhibitors to improve clinical benefit: A systematic review

BACKGROUND

Innovative strategies to fully exploit the antitumor activity of multitargeted tyrosine kinase inhibitors (TKIs) are urgently needed. Higher concentrations of TKIs at their target site, i.e. intratumorally, may lead to broader kinase inhibition, which might be essential for the optimal suppression of tumor growth and induction of apoptosis. To reach these higher intratumoral concentrations, without encountering dose limiting toxicity, alternative TKI dosing strategies employing higher daily and high intermittent doses have been studied. In this systematic review, we evaluated the current clinical evidence to support (intermittent) high TKI dosing regimens.

METHODS

A systematic review was conducted in the following databases: PubMed®, EMBASE® and Cochrane Library©, to evaluate efficacy of alternatively scheduled high-dosed regimen (a higher dose in a regular daily schedule than registered or a higher dose in an alternative intermittent schedule) of TKIs in (haemato-)oncology. Data were extracted independently by two authors according to predefined criteria. Extracted data were tabulated to summarize key findings.

RESULTS

Out of twenty studies that met the inclusion criteria, thirteen investigated higher daily dose schedules of either afatinib, axitinib, erlotinib, gefitinib, imatinib, sorafenib, and sunitinib. Five of these studies included pharmacokinetic analyses, reporting marginal higher maximum drug concentrations (C_max) in plasma (1.3-4-fold higher) compared to the standard dose schedules. Seven clinical trials investigated intermittent high-dose schedules requiring treatment breaks, with the following TKIs: afatinib, erlotinib, gefitinib, lapatinib, sorafenib, and sunitinib. Six of these included pharmacokinetic results, all reporting higher (2-21-fold) C_max in plasma compared to the standard daily dose schedule, with manageable toxicity. No data on tumor concentrations were presented. Data on the efficacy outcomes were limited due to small sample size, study designs, phase 1 population and heterogeneous tumor types.

CONCLUSIONS

Early phase clinical studies show that high-dose intermittent TKI-treatment schedules can lead to an increased C_max compared to standard (low-dose) daily administration with manageable toxicity. These higher concentrations are assumed to reflect higher intratumoral concentrations. Further investigation of the potential improvement in clinical benefit of a high-dose intermittent strategy with multitargeting TKIs is warranted.

Nomogram for predicting overall survival in colorectal cancer with distant metastasis

Background

Colorectal cancer (CRC) is a major cancer burden, and prognosis is determined by many demographic and clinicopathologic factors. The present study aimed to construct a prognostic nomogram for colorectal cancer patients with distant metastasis.

Methods

Colorectal cancer patients with distant metastasis diagnosed between 2010 and 2016 were selected from the Surveillance, Epidemiology, and End Results database. Cox proportional hazards regression was used to identify independent prognostic factors. A nomogram was constructed to predict survival, and validation was performed.

Results

A total of 7099 stage IV colorectal cancer patients were enrolled in the construction cohort. The median overall survival was 20.0 (95% CI 19.3–20.7) months. Age at diagnosis, marital status, race, primary tumour site, tumour grade, CEA level, T stage, N stage, presence of bone, brain, liver and lung metastasis, surgery for primary site and performance of chemotherapy were independent prognostic factors. The nomogram was constructed and the calibration curve showed satisfactory agreement. The C-index was 0.742 (95% CI 0.726–0.758). In the validation cohort (7098 patients), the nomogram showed satisfactory discrimination and calibration with a C-index of 0.746 (95% CI 0.730–0.762).

Conclusion

A series of factors associated with the survival of CRC patients with distant metastasis were found. Based on the identified factors, a nomogram was generated to predict the survival of stage IV colorectal cancer patients. The predictive model showed satisfactory discrimination and calibration, which can provide a reference for survival estimation and individualized treatment decisions.

GUCY2C as a biomarker to target precision therapies for patients with colorectal cancer

Introduction

Colorectal cancer (CRC) is one of the most-deadly malignancies worldwide. Current therapeutic regimens for CRC patients are relatively generic, based primarily on disease type and stage, with little variation. As the field of molecular oncology advances, so too must therapeutic management of CRC. Understanding molecular heterogeneity has led to a new-found promotion for precision therapy in CRC; underlining the diversity of molecularly targeted therapies based on individual tumor characteristics.

Areas covered

We review current approaches for the treatment of CRC and discuss the potential of precision therapy in advanced CRC. We highlight the utility of the intestinal protein guanylyl cyclase C (GUCY2C), as a multi-purpose biomarker and unique therapeutic target in CRC. Here, we summarize current GUCY2C-targeted approaches for treatment of CRC.

Expert opinion

The GUCY2C biomarker has multi-faceted utility in medicine. Developmental investment of GUCY2C as a diagnostic and therapeutic biomarker offers a variety of options taking the molecular characteristics of cancer into account. From GUCY2C-targeted therapies, namely cancer vaccines, CAR-T cells, and monoclonal antibodies, to GUCY2C agonists for chemoprevention in those who are at high risk for developing colorectal cancer, the utility of this protein provides many avenues for exploration with significance in the field of precision medicine.

A newly identified small molecular compound acts as a protein kinase inhibitor to suppress metastasis of colorectal cancer

BACKGROUND

Targeted therapy has demonstrated high efficacy in the treatment of advanced cancer, and protein kinase inhibitors are a major focus of that therapy; therefore, our study aimed to identify a new protein kinase inhibitor that could be used in the treatment of advanced cancers.

METHODS

We analyzed the expression profile of colorectal cancer (CRC), combined the driver gene and drug target databases, and identified protein kinase kalirin RhoGEF kinase (kalirin/KALRN) which is related to CRC metastasis. Based on the structure of kalirin, we screened for the small molecular compound ZINC65387069. We first compared the kinase inhibitory activities and molecular properties of ZINC65387069 and tyrosine kinase inhibitors (TKIs). We then determined the effects of ZINC65387069 on the phosphorylation of protein kinase B-Raf. Finally, we determined the effects of ZINC65387069 on migration and apoptosis of HCT116 cells as well as RKO cells. The cell cytoskeleton was also determined.

RESULTS

Compared with traditional TKIs, ZINC65387069 had stronger kinase inhibitory activity, a simpler structure, higher water solubility, a smaller polar surface area, and lower molecular weight and volume. In CRC cells, ZINC65387069 could significantly inhibit the phosphorylation of B-Raf as well as inhibit cell migration, destroy the cell cytoskeleton, and promote cell apoptosis.

CONCLUSION

ZINC65387069 is a newly identified protein kinase inhibitor that deserves additional research as a lead compound for drug development to help create targeted therapy against CRC.

Precision Approaches in the Management of Colorectal Cancer: Current Evidence and Latest Advancements Towards Individualizing the Treatment

The genetic and molecular underpinnings of metastatic colorectal cancer have been studied for decades, and the applicability of these findings in clinical decision making continues to evolve. Advancements in translating molecular studies have provided a basis for tailoring chemotherapeutic regimens in metastatic colorectal cancer (mCRC) treatment, which have informed multiple practice guidelines. Various genetic and molecular pathways have been identified as clinically significant in the pathogenesis of metastatic colorectal cancer. These include rat sarcoma (RAS), epithelial growth factor receptor (EGFR), vascular endothelial growth factor VEGF, microsatellite instability, mismatch repair, and v-raf murine sarcoma viral oncogene homolog b1 (BRAF) with established clinical implications. RAS mutations and deficiencies in the mismatch repair pathway guide decisions regarding the administration of anti-EGFR-based therapies and immunotherapy, respectively. Furthermore, there are several emerging pathways and therapeutic modalities that have not entered mainstream use in mCRC treatment and are ripe for further investigation. The well-established data in the arena of targeted therapies provide evidence-based support for the use or avoidance of various therapeutic regimens in mCRC treatment, while the emerging pathways and platforms offer a glimpse into the future of transforming a precision approach into a personalized treatment.

Role of NEU3 Overexpression in the Prediction of Efficacy of EGFR-Targeted Therapies in Colon Cancer Cell Lines

The epidermal growth factor receptor (EGFR), through the MAP kinase and PI3K-Akt-mTOR axis, plays a pivotal role in colorectal cancer (CRC) pathogenesis. The membrane-associated NEU3 sialidase interacts with and desialylates EGFR by promoting its dimerization and downstream effectors’ activation. Among the targeted therapies against EGFR, the monoclonal antibody cetuximab is active only in a subgroup of patients not carrying mutations in the MAP kinase pathway. In order to better understand the EGFR-NEU3 interplay and the mechanisms of pharmacological resistance, we investigated the role of NEU3 deregulation in cetuximab-treated CRC cell lines transiently transfected with NEU3 using Western blot analysis. Our results indicate that NEU3 overexpression can enhance EGFR activation only if EGFR is overexpressed, indicating the existence of a threshold for NEU3-mediated EGFR activation. This enhancement mainly leads to the constitutive activation of the MAP kinase pathway. Consequently, we suggest that the evaluation of NEU3 expression cannot entirely substitute the evaluation of EGFR because EGFR-negative cases cannot be stimulated by NEU3. Furthermore, NEU3-mediated hyperactivation of EGFR is counterbalanced by the administration of cetuximab, hypothesizing that a combined treatment of NEU3- and EGFR-targeted therapies may represent a valid option for CRC patients, which must be investigated in the future.

Patient preferences and predicted relative uptake for targeted therapies in metastatic colorectal cancer: a discrete choice experiment

OBJECTIVE

Ras wild-type metastatic colorectal cancers (mCRC) may be treated with anti-vascular endothelial growth factor (VEGF) or anti-epidermal growth factor receptor (EGFR) agents. We aim to estimate patients' preferences for mCRC treatment and relative importance of cost, efficacy improvement, avoidance of side effects and therapy convenience, and relative uptake between profiles that resemble Bevacizumab (anti-VEGF) and Cetuximab (anti-EGFR), two commonly prescribed mCRC targeted therapies.

METHODS

Discrete choice experiment (DCE) was administered to English- or Chinese-speaking Stage 2 or 3 colon cancer patients at the National Cancer Centre Singapore. DCE attributes comprise progression-free survival (PFS), severity of acne-like skin rashes, severity of bleeding, out-of-pocket cost per month and frequency of drug administration. Mixed logit model was used to calculate preference weights for all attribute levels. Subgroup analyses were conducted by interacting attribute levels with selected respondent characteristics. Relative uptake rates for various medication scenarios were studied.

RESULTS

169 respondents aged 61.5 ± 10.5 years completed the survey. They placed the greatest weight on cost, followed by bleeding and skin rashes, then PFS and finally frequency of drug administration. This was similarly observed in the subgroup analyses. A scenario with shorter PFS but less severe side effects has a slightly higher relative uptake at 55%. One quarter of respondents reported that they would not take the treatment they preferred in the choice task.

CONCLUSION

Patients were willing to trade off some degree of efficacy to avoid certain severity of side effects. It is therefore crucial for patients and physicians to discuss patients' preferences and circumstances to understand which attributes are more important, as well as patients' views on the trade-offs between treatment benefits and risks.

Translating Biomarkers of Cholangiocarcinoma for Theranosis: A Systematic Review

Simple Summary

Bile duct cancers are rare cancers that have poor prospects and limited treatment options. Recently, significant advances have been made in the field of nanomedicine which has allowed new approaches to the diagnosis and treatment (i.e., theranosis) of human diseases. To develop nanomedicines that could earmark or target bile duct cancer, specific proteins (or biomarkers) that are present in bile duct cancer but absent in normal tissues are required. We conducted a systematic search of the published literature for bile duct cancer biomarkers that would be suitable for theranosis. Specialist bioinformatics tools were used to help categorize the resulting data set. To select the most promising biomarkers from the search, biomarkers were ranked according to a theranosis-scoring-system and then evaluated in detail. The biomarkers identified using this approach have the potential to promote targeted nanomedicine-based systems to treat bile duct cancers.

Abstract

Cholangiocarcinoma (CCA) is a rare disease with poor outcomes and limited research efforts into novel treatment options. A systematic review of CCA biomarkers was undertaken to identify promising biomarkers that may be used for theranosis (therapy and diagnosis). MEDLINE/EMBASE databases (1996–2019) were systematically searched using two strategies to identify biomarker studies of CCA. The PANTHER Go-Slim classification system and STRING network version 11.0 were used to interrogate the identified biomarkers. The TArget Selection Criteria for Theranosis (TASC-T) score was used to rank identified proteins as potential targetable biomarkers for theranosis. The following proteins scored the highest, CA9, CLDN18, TNC, MMP9, and EGFR, and they were evaluated in detail. None of these biomarkers had high sensitivity or specificity for CCA but have potential for theranosis. This review is unique in that it describes the process of selecting suitable markers for theranosis, which is also applicable to other diseases. This has highlighted existing validated markers of CCA that can be used for active tumor targeting for the future development of targeted theranostic delivery systems. It also emphasizes the relevance of bioinformatics in aiding the search for validated biomarkers that could be repurposed for theranosis.

Identification of long non-coding RNA SCARNA9L as a novel molecular target for colorectal cancer

The aim of the present study was to analyze the microarray data of human colorectal cancer (CRC) tissues and identify novel therapeutic targets for CRC. Microarray analysis from the GSE73360 and GSE84984 datasets was performed to identify novel long non-coding RNAs (lncRNAs) that were differentially expressed in human CRC tissues. Additionally, small interfering RNAs were used to deplete the expression of the indicated lncRNAs in cells. Colony-formation, wound-closure, and transwell assays were performed on CRC cells to assess their proliferation and migration capacities. Through microarray analysis, SCARNA9L, SLMO2-ATP5E and LOC100132062 were identified as differentially expressed lncRNAs in CRC tissues. The present study demonstrated that the ablation of SCARNA9L inhibited cell proliferation and arrested the cell cycle of SW480 and SW620 CRC cells. Additionally, depletion of SCARNA9L restrained the migration of CRC cells in vitro. Overall, the present study investigated the potential involvement of SCARNA9L in CRC and suggests SCARNA9L as a potential biomarker.

The Targeted Therapies Era Beyond the Surgical Point of View: What Spine Surgeons Should Know Before Approaching Spinal Metastases

In the last few years, the treatment of spinal metastases has significantly changed. This is due to the advancements in surgical technique, radiotherapy, and chemotherapy which have enriched the multidisciplinary management. Above all, the field of molecular biology of tumors is in continuous and prosperous evolution. In this review, the molecular markers and new approaches that have radically modified the chemotherapeutic strategy of the most common metastatic neoplasms will be examined together with clinical and surgical implications. The experience and skills of several different medical professionals are mandatory: an interdisciplinary oncology team represents the winning strategy in the treatment of patients with spinal metastases

Projected estimates of cancer in Canada in 2020

BACKGROUND

Cancer projections to the current year help in policy development, planning of programs and allocation of resources. We sought to provide an overview of the expected incidence and mortality of cancer in Canada in 2020 in follow-up to the Canadian Cancer Statistics 2019 report.

METHODS

We obtained incidence data from the National Cancer Incidence Reporting System (1984-1991) and Canadian Cancer Registry (1992-2015). Mortality data (1984-2015) were obtained from the Canadian Vital Statistics - Death Database. All databases are maintained by Statistics Canada. Cancer incidence and mortality counts and age-standardized rates were projected to 2020 for 23 cancer types by sex and geographic region (provinces and territories) for all ages combined.

RESULTS

An estimated 225 800 new cancer cases and 83 300 cancer deaths are expected in Canada in 2020. The most commonly diagnosed cancers are expected to be lung overall (29 800), breast in females (27 400) and prostate in males (23 300). Lung cancer is also expected to be the leading cause of cancer death, accounting for 25.5% of all cancer deaths, followed by colorectal (11.6%), pancreatic (6.4%) and breast (6.1%) cancers. Incidence and mortality rates will be generally higher in the eastern provinces than in the western provinces.

INTERPRETATION

The number of cancer cases and deaths remains high in Canada and, owing to the growing and aging population, is expected to continue to increase. Although progress has been made in reducing deaths for most major cancers (breast, prostate and lung), there has been limited progress for pancreatic cancer, which is expected to be the third leading cause of cancer death in Canada in 2020. Additional efforts to improve uptake of existing programs, as well as to advance research, prevention, screening and treatment, are needed to address the cancer burden in Canada.

Targeting Epidermal Growth Factor Receptor (EGFR) in Pediatric Colorectal Cancer

Background: Colorectal carcinoma (CRC) is very rare in the pediatric and adolescent age range and clinical management is performed according to adult protocols. We report, for the first time in the literature, a case of a child with metastatic CRC successfully treated with panitumumab associated to chemotherapy. Methods: A twelve-year-old male was diagnosed with CRC with nodal metastasis and peritoneal neoplastic effusion. After performing a genetic evaluation, in light of the absence of mutations in RAS family genes, anti-Epidermal Growth Factor Receptor (EGFR) monoclonal antibody, panitumumab, was added to chemotherapy FOLFOXIRI. Results: The child successfully responded to therapy with normalization of the Carbohydrate Antigen (CA) 19.9 value after the third cycle of treatment. After the sixth cycle, he underwent surgery that consisted in sigmoid resection with complete D3 lymphadenectomy. At histological evaluation, no residual neoplastic cells were detectable in the surgical specimen. He completed 12 cycles of chemotherapy plus panitumomab and he is alive without disease 14 months from diagnosis. Conclusions: Our results suggest performing mutational screening for colorectal cancer also in the pediatric setting, in order to orient treatment that should include targeted therapies.

Pyrrole derivatives as potential anti-cancer therapeutics: synthesis, mechanisms of action, safety

Pyrrole derivatives (PDs) chloro-1-(4-chlorobenzyl)-4-((3-(trifluoromethyl)phenyl)amino)-1H-pyrrole-2,5-dione (MI-1) and 5-amino-4-(1,3-benzothyazol-2-yn)-1-(3-methoxyphenyl)-1,2-dihydro-3H-pyrrole-3-one (D1) were synthesised as inhibitors of several protein kinases including EGFR and VEGFR. The aim of the study was to reveal the exact mechanisms of PDs' action EGFR and VEGFR are involved in. We observed, that both PDs could bind with EGFR and VEGFR and form stable complexes. PDs entered into electrostatic interactions with polar groups of phospholipid heads in cell membrane, and the power of interaction depended on the nature of PD radical substituents (greater for MI-1 and smaller for D1). Partial intercalation of MI-1 into the membrane hydrophobic zone also occurred. PDs concentrations induced apoptosis in malignant cells but normal ones had different sensitivity to those. MI-1 and D1 acted like antioxidants in inflamed colonic tissue, as evidenced by reduce of lipid and protein peroxidation products (by 43-67%) and increase of superoxide dismutase activity (by 40 and 58%) with restoring these values to control ones. MI-1 restored reduced haemoglobin and normalised elevated platelets and monocytes in settings of colorectal cancer, whereas D1 normalised only platelets. Thus, MI-1 and D1 could be used as competitive inhibitors of EGFR and VEGFR and antioxidants, which might contribute to realisation of their anti-inflammatory, proapoptotic and antitumor activity.

Exploring the Pharmacological Mechanism of the Herb Pair "HuangLian-GanJiang" against Colorectal Cancer Based on Network Pharmacology

Since the herb pair Huang Lian-Gan Jiang (HL-GJ) was put forward as conventional compatibility for cold-heat regulation in the middle energizer in the theory of Traditional Chinese Medicine (TCM), their therapeutic effects were observed on the prevention and treatment of intestinal inflammation and tumors including colorectal cancer (CRC). However, the active compounds, crucial targets, and related pathways of HL-GJ against CRC remained unclear. The purpose of this research was to establish a comprehensive and systemic approach that could identify the active compounds, excavate crucial targets, and reveal anti-CRC mechanisms of HL-GJ against CRC based on network pharmacology. We used methods including chemical compound screening based on absorption, distribution, metabolism, and excretion (ADME), compound target prediction, CRC target collection, network construction and analysis, Gene Ontology (GO), and pathway analysis. In this study, eight main active compounds of HL-GJ were identified, including Gingerenone C, Isogingerenone B, 5,8-dihydroxy-2-(2-phenylethyl) Chromone, 2,3,4-trihydroxy-benzenepropanoic acid, 3,4-dihydroxyphenylethyl Alcohol Glucoside, 3-carboxy-4-hydroxy-phenoxy Glucoside, Moupinamide, and Obaculactone. HRAS, KRAS, PIK3CA, PDE5A, PPARG, TGFBR1, and TGFBR2 were identified as crucial targets of HL-GJ against CRC. There were mainly 500 biological processes and 70 molecular functions regulated during HL-GJ against CRC (P < 0.001). There were mainly 162 signaling pathways contributing to therapeutic effects (P < 0.001), the top 10 of which included DAP12 signaling, signaling by PDGF, signaling by EGFR, NGF signaling via TRKA from the plasma membrane, signaling by NGF, downstream signal transduction, DAP12 interactions, signaling by VEGF, signaling by FGFR3, and signaling by FGFR4. The study established a comprehensive and systematic paradigm to understand the pharmacological mechanisms of multiherb compatibility such as an herb pair, which might accelerate the development and modernization of TCM.

The McCAVE Trial: Vanucizumab plus mFOLFOX-6 Versus Bevacizumab plus mFOLFOX-6 in Patients with Previously Untreated Metastatic Colorectal Carcinoma (mCRC)

Background

Bevacizumab, a VEGF‐A inhibitor, in combination with chemotherapy, has proven to increase progression‐free survival (PFS) and overall survival in multiple lines of therapy of metastatic colorectal cancer (mCRC). The angiogenic factor angiopoetin‐2 (Ang‐2) is associated with poor prognosis in many cancers, including mCRC. Preclinical models demonstrate improved activity when inhibiting both VEGF‐A and Ang‐2, suggesting that the dual VEGF‐A and Ang‐2 blocker vanucizumab (RO5520985 or RG‐7221) may improve clinical outcomes. This phase II trial evaluated the efficacy of vanucizumab plus modified (m)FOLFOX‐6 (folinic acid (leucovorin), fluorouracil (5‐FU) and oxaliplatin) versus bevacizumab/mFOLFOX‐6 for first‐line mCRC.

Patients and Methods

All patients received mFOLFOX‐6 and were randomized 1:1 to also receive vanucizumab 2,000 mg or bevacizumab 5 mg/kg every other week. Oxaliplatin was given for eight cycles; other agents were continued until disease progression or unacceptable toxicity for a maximum of 24 months. The primary endpoint was investigator‐assessed PFS.

Results

One hundred eighty‐nine patients were randomized (vanucizumab, n = 94; bevacizumab, n = 95). The number of PFS events was comparable (vanucizumab, n = 39; bevacizumab, n = 43). The hazard ratio was 1.00 (95% confidence interval, 0.64–1.58; p = .98) in a stratified analysis based on number of metastatic sites and region. Objective response rate was 52.1% and 57.9% in the vanucizumab and bevacizumab arm, respectively. Baseline plasma Ang‐2 levels were prognostic in both arms but not predictive for treatment effects on PFS of vanucizumab. The incidence of adverse events of grade ≥3 was similar between treatment arms (83.9% vs. 82.1%); gastrointestinal perforations (10.8% vs. 8.4%) exceeded previously reported rates in this setting. Hypertension and peripheral edema were more frequent in the vanucizumab arm.

Conclusion

Vanucizumab/mFOLFOX‐6 did not improve PFS and was associated with increased rates of antiangiogenic toxicity compared with bevacizumab/mFOLFOX‐6. Our results suggest that Ang‐2 is not a relevant therapeutic target in first‐line mCRC.

Implications for Practice

This randomized phase II study demonstrates that additional angiopoietin‐2 (Ang‐2) inhibition does not result in superior benefit over anti–VEGF‐A blockade alone when each added to standard chemotherapy. Moreover, the performed pharmacokinetic and pharmacodynamic analysis revealed that vanucizumab was bioavailable and affected its intended target, thereby strongly suggesting that Ang‐2 is not a relevant therapeutic target in the clinical setting of treatment‐naïve metastatic colorectal cancer. As a result, the further clinical development of the dual VEGF‐A and Ang‐2 inhibitor vanucizumab was discontinued.

This phase II trial evaluated the efficacy of vanucizumab plus mFOLFOX‐6 versus bevacizumab/mFOLFOX‐6 in the first‐line setting of metastatic colorectal cancer.

The Evolving Biomarker Landscape for Treatment Selection in Metastatic Colorectal Cancer

The approval of targeted therapies for metastatic colorectal cancer (mCRC) has led to important improvements in patient outcomes. However, it is still necessary to increase individualisation of treatments based on tumour genetic profiles to optimise efficacy, while minimising toxicity. As such, there is currently great focus on the discovery and validation of further biomarkers in mCRC, with many new potential prognostic and predictive markers being identified alongside developments in patient molecular profiling technologies. Here, we review data for validated and emerging biomarkers impacting treatment strategies in mCRC. We completed a structured literature search of the PubMed database to identify relevant publications, limiting for English-language publications published between 1 January 2014 and 11 July 2018. In addition, we performed a manual search of the key general oncology and CRC-focused congresses to identify abstracts reporting emerging mCRC biomarker data, and of ClinicalTrials.gov to identify ongoing clinical trials investigating emerging biomarkers in mCRC and/or molecular-guided clinical trials. There is solid evidence supporting the use of BRAF status as a prognostic biomarker and DYPD, UGT1A1, RAS, and microsatellite instability as predictive biomarkers in mCRC. There are a number of emerging biomarkers that may prove to be clinically relevant in the future to have prognostic (HPP1 methylation), predictive (HER3, microRNAs, anti-angiogenic markers, and CRC intrinsic subtypes), or both prognostic and predictive values (HER2, CpG island methylator phenotype, tumour mutational load, gene fusions, and consensus molecular subtypes). As such, new biomarker-led treatment strategies in addition to anti-epidermal growth factor receptor and anti-angiogenetic treatments are being explored. Biomarkers that are not recommended to be tested in clinical practice or are unlikely to be imminently clinically relevant for mCRC include thymidylate transferase, ERCC1, PIK3CA, and PTEN. We highlight the clinical utility of existing and emerging biomarkers in mCRC and provide recommended treatment strategies according to the biomarker status. An update on ongoing molecular-guided clinical trials is also provided.

Long non-coding RNA SNHG12 promotes proliferation and invasion of colorectal cancer cells by acting as a molecular sponge of microRNA-16

Long non-coding (lnc)RNA small nucleolar RNA host gene 12 (SNHG12) has an oncogenic role in various common human cancer types, including colorectal cancer (CRC). However, the detailed regulatory mechanisms of SNHG12 in CRC cells have remained largely elusive, and the investigation thereof was the purpose of the present study. Polymerase chain reaction analysis was performed to examine the expression of lncRNA and microRNA (miR). Cell Counting Kit-8 and Transwell assays were used to assess cell proliferation and invasion. A luciferase reporter assay was performed to confirm a predicted targeting association between lncRNA and miR. It was observed that SNHG12 was markedly upregulated in CRC tissues when compared with that in adjacent non-tumour tissues, and its high expression was associated with CRC progression, as well as poor prognosis of patients. In addition, the expression of SNHG12 was higher in CRC cell lines when compared with that in a normal intestinal epithelial cell line. Knockdown of SNHG12 significantly inhibited CRC cell proliferation and invasion, while ectopic overexpression of SNHG12 had the opposite effect. A Bioinformatics analysis predicted that SNHG12 and miR-16 have complementary binding sites, which was confirmed by a luciferase reporter gene assay. The expression levels of miR-16 were markedly decreased in CRC tissues and cell lines compared with those in normal tissues or cells, and were inversely correlated with the expression levels of SNHG12 in CRC tissues. Furthermore, silencing of miR-16 eliminated the suppressive effects of SNHG12 knockdown on CRC cell proliferation and invasion. In conclusion, the present study demonstrated that SNHG12 promotes CRC cell proliferation and invasion, at least in part, by acting as a molecular sponge of miR-16, suggesting that SNHG12 may be a promising therapeutic target for CRC.