Targeted therapies in colorectal cancer-an integrative view by PPPM

Multivariate Risk Analysis of RAS, BRAF and EGFR Mutations Allelic Frequency and Coexistence as Colorectal Cancer Predictive Biomarkers

Simple Summary

The colorectal cancer (CRC) stage and evolution should be described by biomarker profiles. In 60 CRC cases, KRAS, NRAS, BRAF, and EGFR mutations were analyzed by droplet digital PCR (ddPCR). KRAS G12/G13 mutation was present in all patients with variable allelic frequencies. KRAS Q61 mutation was correlated with tumor invasion beyond the subserosa and poor differentiation, both associated with worst prognosis. Tumors with NRAS and BRAF mutations were prevalently localized on the right segment colon. The discovery of the KRAS Q61 role in tumor phenotypes provides the foundation for new therapeutic strategies and perspectives on molecular subtypes classification of CRC.

Abstract

Background: Biomarker profiles should represent a coherent description of the colorectal cancer (CRC) stage and its predicted evolution. Methods: Using droplet digital PCR, we detected the allelic frequencies (AF) of KRAS, NRAS, BRAF, and EGFR mutations from 60 tumors. We employed a pair-wise association approach to estimate the risk involving AF mutations as outcome variables for clinical data and as predicting variables for tumor-staging. We evaluated correlations between mutations of AFs and also between the mutations and histopathology features (tumor staging, inflammation, differentiation, and invasiveness). Results: KRAS G12/G13 mutations were present in all patients. KRAS Q61 was significantly associated with poor differentiation, high desmoplastic reaction, invasiveness (ypT4), and metastasis (ypM1). NRAS and BRAF were associated with the right-side localization of tumors. Diabetic patients had a higher risk to exhibit NRAS G12/G13 mutations. BRAF and NRAS G12/G13 mutations co-existed in tumors with invasiveness limited to the submucosa. Conclusions: The associations we found and the mutational AF we reported may help to understand disease processes and may be considered as potential CCR biomarker candidates. In addition, we propose representative mutation panels associated with specific clinical and histopathological features of CRC, as a unique opportunity to refine the degree of personalization of CRC treatment.

Predictive factors, preventive implications, and personalized surgical strategies for bone metastasis from lung cancer: population-based approach with a comprehensive cancer center-based study

Background

Bone metastasis (BM) and skeletal-related events (SREs) happen to advanced lung cancer (LC) patients without warning. LC-BM patients are often passive to BM diagnosis and surgical treatment. It is necessary to guide the diagnosis and treatment paradigm for LC-BM patients from reactive medicine toward predictive, preventive, and personalized medicine (PPPM) step by step.

Methods

Two independent study cohorts including LC-BM patients were analyzed, including the Surveillance, Epidemiology, and End Results (SEER) cohort (n = 203942) and the prospective Fudan University Shanghai Cancer Center (FUSCC) cohort (n = 59). The epidemiological trends of BM in LC patients were depicted. Risk factors for BM were identified using a multivariable logistic regression model. An individualized nomogram was developed for BM risk stratification. Personalized surgical strategies and perioperative care were described for FUSCC cohort.

Results

The BM incidence rate in LC patients grew (from 17.53% in 2010 to 19.05% in 2016). Liver metastasis was a significant risk factor for BM (OR = 4.53, 95% CI = 4.38-4.69) and poor prognosis (HR = 1.29, 95% CI = 1.25-1.32). The individualized nomogram exhibited good predictive performance for BM risk stratification (AUC = 0.784, 95%CI = 0.781-0.786). Younger patients, males, patients with high invasive LC, and patients with other distant site metastases should be prioritized for BM prevention. Spine is the most common site of BM, causing back pain (91.5%), pathological vertebral fracture (27.1%), and difficult walking (25.4%). Spinal surgery with personalized spinal reconstruction significantly relieved pain and improved daily activities. Perioperative inflammation, immune, and nutrition abnormities warrant personalized managements. Radiotherapy needs to be recommended for specific postoperative individuals.

Conclusions

The presence of liver metastasis is a strong predictor of LC-BM. It is recommended to take proactive measures to prevent BM and its SREs, particularly in young patients, males, high invasive LC, and LC with liver metastasis. BM surgery and perioperative management are personalized and required. In addition, adjuvant radiation following separation surgery must also be included in PPPM-guided management.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-022-00270-9.

Nanomedicines in the treatment of colon cancer: a focus on metallodrugs

Worldwide, colon cancer (CC) represents the fourth most common type of cancer and the fifth major cause of cancer-associated deaths. Surgical resection is considered the standard therapeutic choice for CC in early stages. However, in latter stages of the disease, adjuvant chemotherapy is essential for an appropriate management of this pathology. Metal-based complexes displaying cytotoxic properties towards tumor cells emerge as potential chemotherapeutic options. One metallodrug, oxaliplatin, was already approved for clinical use, playing an important role in the treatment of CC patients. Unfortunately, most of the newly designed metal-based complexes exhibit lack of selectivity against cancer cells, low solubility and permeability, high dose-limiting toxicity, and emergence of resistances. Nanodelivery systems enable the incorporation of metallodrugs at adequate payloads, solving the above-referred drawbacks. Moreover, drug delivery systems, depending on their physicochemical properties, are able to release the incorporated material preferentially at affected tissues/organs, enhancing the therapeutic activity in vivo, with concomitant fewer side effects. In this review, the general features and therapeutic management of CC will be addressed, with a special focus on preclinical or clinical studies using metal-based compounds. Furthermore, the use of different nanodelivery systems will also be described as tools to potentiate the therapeutic index of metallodrugs for the management of CC.

Possible Enhancement of Photodynamic Therapy (PDT) Colorectal Cancer Treatment when Combined with Cannabidiol

Colorectal Cancer (CRC) has a high mortality rate and is one of the most difficult diseases to manage due to tumour resistance and metastasis. The treatment of choice for CRC is reliant on the phase and time of diagnosis. Despite several conventional treatments available to treat CRC (surgical excision, chemo-, radiationand immune-therapy), resistance is a major challenge, especially if it has metastasized. Additionally, these treatments often cause unwanted adverse side effects and so it remains imperative to investigate alternative combination therapies. Photodynamic Therapy (PDT) is a promising treatment modality for the primary treatment of CRC, since it is non-invasive, has few side effects and selectively damages only cancerous tissues, leaving adjacent healthy structures intact. PDT involves three fundamentals: a Photosensitizer (PS) drug localized in tumour tissues, oxygen, and light. Upon PS excitation using a specific wavelength of light, an energy transfer cascade occurs, that ultimately yields cytotoxic species, which in turn induces cell death. Cannabidiol (CBD) is a cannabinoid compound derived from the Cannabis sativa plant, which has shown to exert anticancer effects on CRC through different pathways, inducing apoptosis and so inhibiting tumour metastasis and secondary spread. This review paper highlights current conventional treatment modalities for CRC and their limitations, as well as discusses the necessitation for further investigation into unconventional active nanoparticle targeting PDT treatments for enhanced primary CRC treatment. This can be administered in combination with CBD, to prevent CRC secondary spread and enhance the synergistic efficacy of CRC treatment outcomes, with less side effects.

Bio- and Hemo-Compatible Silk Fibroin PEGylated Nanocarriers for 5-Fluorouracil Chemotherapy in Colorectal Cancer: In Vitro Studies

5-fluorouracil (5-FU) remains the gold standard of treatment for colorectal cancer, but its poor bioavailability and high systemic toxicity highlight the urgent need for the development of novel delivery strategies to increase the efficacy of 5-FU treatment. The present study is aimed to design and validate a PEGylated Silk Fibroin Nanocarrier (SF/PEG nanoparticles (NPs)) as an efficient 5-FU delivery system for potential intravenous administration. Using the human adenocarcinoma HT–29 cell line as an in vitro model for colorectal cancer, the cytotoxicity screening of the SF/PEG NPs showed that pristine nanocarriers were highly biocompatible, while the addition of 5-FU triggers a dramatic reduction in tumor cell viability, proliferation potential and mitochondrial integrity as well as a significant increase in nitric oxide production. Despite their high in vitro cytotoxicity, the 5-FU SF/PEG NPs were found hemocompatible as no impact on red blood cells hemolysis or the phagocytic activity of the granulocytes was observed. Exposure of HT–29 tumor cells and blood samples to 5-FU SF/PEG NPs augmented the tumor necrosis factor-α levels. Moreover, 5-FU SF/PEG NPs showed an impact on tumor cell migration and invasive potential as both of these processes were inhibited by the NP treatment.

Apoptosis induction by siRNA targeting integrin-β1 and regorafenib/DDAB-mPEG-PCL hybrid nanoparticles in regorafenib-resistant colon cancer cells

Colorectal cancer (CRC) is regarded as the third most common cancer worldwide. Although Regorafenib as a receptor tyrosine kinase inhibitor (RTKI) disrupts tumor growth and angiogenesis in metastatic CRC (mCRC) patients, drug resistance leads to poor prognosis and survival. Integrin-β1 overexpression has been proposed to be the major player in this regard. Herein, the Regorafenib-resistant human colon cancer cell line (SW-48) was induced, and the Integrin-β1 gene expression, as well as apoptosis, was assessed through the combination of small interfering RNA (siRNA) targeting Integrin-β1 and Regorafenib/Dimethyldioctadecylammonium bromide (DDAB)-methoxy poly (ethylene glycol) (mPEG)-poly-ε-caprolactone (PCL) hybrid nanoparticles (HNPs). In the current study, Regorafenib-resistant SW-48 cell line was generated in which the Regorafenib half-maximal inhibitory concentration (IC₅₀) for non-resistant and resistant cells was 13.5±1.5 µM and 55.1±0.8 µM, respectively. The results of DLS also demonstrated that the size and the charge of the HNPs were equal to 66.56±0.5 nm and +29.5±1.2 mv, respectively. In addition, the Integrin-β1 gene expression was significantly higher in resistant cells than in non-resistant ones (P<0.05). The siRNA/HNP complexes in combination with Regorafenib/HNPs were accordingly identified as the most effective treatment to decrease the Integrin-β1 gene expression and to enhance the apoptosis rate in resistant cells (P<0.001). Overall, the study indicated that combination therapy using siRNA/HNP and Regorafenib/HNPs complex could down-regulate the Integrin-β1 gene expression and consequently trigger apoptosis, and this may potentially induce drug sensitivity.

Assessment of mismatch repair deficiency, CDX2, beta-catenin and E-cadherin expression in colon cancer: molecular characteristics and impact on prognosis and survival - an immunohistochemical study

Microsatellite instability (MSI) or the deficiency of mismatch repair (MMR) proteins is one of the molecular pathways of colorectal tumorigenesis and may have important clinical implications in predicting the treatment response. We evaluated the relationship between clinicopathological features and MMR proteins [mutL homologue 1 (MLH1), mutS homologue 2 (MSH2), mutS homologue 6 (MSH6), postmeiotic segregation increased 2 (PMS2)], adhesion molecules (E-cadherin, beta-catenin) and caudal-type homeobox 2 (CDX2) in 31 patients with colon adenocarcinoma, using immunohistochemistry. We also aimed to assess the prognostic value of the studied proteins. MLH1 loss was correlated to PMS2 loss (p=0.006) and MSH2 loss (p=0.023); MSH2 loss was significantly associated to MSH6 loss (p=0.011). Tumors with MSH6 loss, together with tumors with PMS2 loss, covered all the patients with MSI status. We found a significant correlation between MSI tumors and mucinous histological type (p=0.03), but no significant associations with other clinicopathological features or with survival rate. There was a significant correlation between E-cadherin expression and differentiation degree (p=0.018) and between beta-catenin expression and lymph node invasion (p=0.046). No significant association between CDX2 loss and any clinical or pathological features was found (p>0.05). No significant differences were identified in overall survival according to E-cadherin, beta-catenin or CDX2 expression (p>0.05). In our study, PMS2 loss was significantly correlated with CDX2 loss (p=0.03). In conclusion, the molecular analysis of biological markers for colon cancer may be important for patient stratification, in order to select the optimal treatment algorithm. Our results suggest that probably the double panel (MSH6 and PMS2) is enough to detect the MSI status, instead of using the quadruple panel.

Synthesis and cytotoxic activity of organotin(IV) diallyldithiocarbamate compounds as anticancer agent towards colon adenocarcinoma cells (HT-29)

Context

Diphenyltin(IV) diallyldithiocarbamate compound (Compound 1) and triphenyltin(IV) diallyldithiocarbamate compound (Compound 2) are two newly synthesised compounds of organotin(IV) with diallyldithiocarbamate ligands.

Objective

To assess the cytotoxic effects of two synthesised compounds against HT-29 human colon adenocarcinoma cells and human CCD-18Co normal colon cells.

Materials and methods

Two successfully synthesised compounds were characterised using elemental (carbon, hydrogen, nitrogen, and sulphur) analysis, Fourier-Transform Infrared (FTIR), and ¹H, ¹³C ¹¹⁹Sn Nucleus Magnetic Resonance (NMR) spectroscopies. The single-crystal structure of both compounds was determined by X-ray single-crystal analysis. The cytotoxicity of the compounds was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazholium bromide (MTT) assay upon 24 h of treatment. While the mode of cell death was determined based on the externalisation of phosphatidylserine using a flow cytometer.

Results

The elemental analysis data of the two compounds showed an agreement with the suggested formula of (C₆H₅)₂Sn[S₂CN(C₃H₅)₂]₂ for Compound 1 and (C₆H₅)₃Sn[S₂CN(C₃H₅)₂] for Compound 2. The two major peaks of infrared absorbance, i.e., ν(C = N) and ν(C = S) were detected at the range of 1475–1479 cm⁻¹ and 972–977 cm⁻¹, respectively. The chemical shift of carbon in NCS₂ group for Compound 1 and 2 were found at 200.82 and 197.79 ppm. The crystal structure of Compound 1 showed that it is six coordinated and crystallised in monoclinic, P2₁/c space group. While the crystal structure of Compound 2 is five coordinated and crystallised in monoclinic, P2₁/c space group. The cytotoxicity (IC₅₀) of the two compounds against HT-29 cell were 2.36 μM and 0.39 μM. Meanwhile, the percentage of cell death modes between 60% and 75% for compound 1 and compound 2 were mainly due to apoptosis, suggesting that both compounds induced growth arrest.

Conclusion

Our study concluded that the synthesised compounds showed potent cytotoxicity towards HT-29 cell, with the triphenyltin(IV) compound showing the highest effect compared to diphenyltin(IV).

Recent developments in antibody derivatives against colorectal cancer; A review

Colorectal cancer (CRC) is the fourth most common cause of cancer and mortality worldwide and is the third most common cancer in men and women. Surgery, radiotherapy, and chemotherapy are conventionally used for the treatment of colorectal cancer. However, these methods are associated with various side effects on normal cells. Thus, new studies are moving towards more effective and non-invasive methods for treatment of colorectal cancer. Targeted therapy of CRC is a promising new approach to enhance the efficiency and decrease the toxicity of the treatment. In targeted therapy of CRC, antibody fragments can directly inhibit tumor cell growth and proliferation. They also can act as an ideal carrier for targeted delivery of anticancer drugs. In the present study, the structure and function of different formats of antibody fragments, immune-targeted therapy of CRC using antibody fragments will be discussed.

Identification of colorectal cancers with defective DNA damage repair by immunohistochemical profiling of mismatch repair proteins, CDX2 and BRCA1

Colorectal cancer (CRC) is a complex disease as shown by consensus classification. The present study attempted to identify subtypes with known prognostic markers for better clinical management. A total of 72 CRC tumors were examined for the expression of mismatch repair (MMR) proteins, along with caudal-type homeobox protein 2 (CDX2) and BRCA1, by immunohistochemistry. Tumors were assigned based on the presence or loss of MMR proteins as proficient or deficient. Correlations were examined with CDX2 and BRCA1 along with clinico-pathological features. Expressional pattern of microRNAs (miRs/miRNAs), such as miR-183-96-182, known to be associated with defective DNA damage repair were evaluated by reverse transcription-quantitative PCR. A total of 22% of the CRC tumors were assigned as deficient in mismatch repair. 71% of the tumors expressed CDX2 while only 21% had nuclear expression of BRCA1. Loss of CDX2 protein was higher in the deficient subtype compared with the proficient subtype. A total of 14% of the tumors had dual loss of MMR and BRCA1 proteins and showed aggressive clinical features in addition to elevated expression of DNA damage repair microRNAs. The present study shows the presence of a small proportion of colorectal tumors with dual loss of key proteins involved in DNA damage repair which may be amenable to specific therapy. The implication of the present observations warrants investigation in a larger patient cohort with prognostic information.

Differential Expression of HER2 and SKP2 in Benign and Malignant Colorectal Lesions

Background:

Colorectal cancer (CRC) is the fourth most common cancer worldwide. Both HER2 and SKP2 have a carcinogenic role in CRC making them attractive targets for tailored treatment. This work aims to correlate HER2 and SKP2 protein expression as well as HER2 gene amplification with clinicopathological parameters aiming at identifying potential candidates for targeted therapy.

Methods:

This Study was conducted on 127 paraffin-embedded tissue samples of different colorectal lesions [controls, chronic colitis, ulcerative colitis (UC), hyperplastic polyps (HPs), adenomas and CRCs] to investigate HER2 and SKP2 expression by immunohistochemistry (IHC), Selected CRC cases [equivocal (2+) and positive (3+) by IHC] were further evaluated by ISH (CISH and SISH ) to assess HER2 gene amplification.

Results:

Chronic colitis, UC, HPs and adenomas were HER2-negative. HER2 positivity (scores 2+ and 3+) was found only in15% of CRCs. Both SISH and CISH showed the same results with high concordance as 66.7% of equivocal and 100% of positive cases showed amplification of HER2 gene. SKP2 positivity was detected in 26.7% and 45% of adenomas and CRCs respectively, while other studied groups were negative. A significant correlation was noted between HER2 and SKP2 expression.

Conclusion:

A small percent of CRCs exhibited HER2 gene amplification, which would be potential candidates for anti HER2 therapy whereas IHC could be a primary screening test for patient selection. A potential carcinogenic role of SKP2 was suggested by the findings that SKP2 expression was undetectable in normal colonic mucosa but significantly increases from adenoma to carcinoma, hoping adenoma patients to get benefit from targeted therapy.

Diagnostic test assessment. Validation study of an alternative system to detect microsatellite instability in colorectal carcinoma

The American Society for Clinical Pathology (ASCP), College of American Pathologists (CAP), Association for Molecular Pathology (AMP), and the American Society of Clinical Oncology (ASCO) have been recently strongly recommended the evaluation of mismatch repair status (MMS) as molecular biomarkers in colorectal cancer for a better prognostic stratification of patients. This recommendation is emphasized by the recent evidence of Microsatellite Instability (MSI) as a predictive marker for chemotherapy and immunotherapy.

In this scenario, the validation of molecular biomarker testing methods seems to be essential to design the most appropriate tailored therapy and the most suitable care strategy, respectively.

In this study, we validated an alternative method based on capillary electrophoresis system label-free PCR (Qiaxcel system) to evaluate the MSI Bethesda Panel. We also parallel the results with a standard approach.

Our data showed total concordance with the standard approach, with a highly time-efficient and easy procedure combined with high sensitivity for MSI detection.

Alternative capillary electrophoresis based on label-free PCR such as the Qiaxel system is a very sensitive and specific method to detect MSI for the management of patients with colorectal cancer. This procedure is adequate and suitable in diagnostic routine for the evaluation of microsatellite repeats compared to standard procedures.

Overview of Current Immunotherapies Targeting Mutated KRAS Cancers

The occurrence of somatic substitution mutations of the KRAS proto-oncogene is highly prevalent in certain cancer types, which often leads to constant activation of proliferative pathways and subsequent neoplastic transformation. It is often seen as a gateway mutation in carcinogenesis and has been commonly deemed as a predictive biomarker for poor prognosis and relapse when conventional chemotherapeutics are employed. Additionally, its mutational status also renders EGFR targeted therapies ineffective owing to its downstream location. Efforts to discover new approaches targeting this menacing culprit have been ongoing for years without much success, and with incidences of KRAS positive cancer patients being on the rise, researchers are now turning towards immunotherapies as the way forward. In this scoping review, recent immunotherapeutic developments and advances in both preclinical and clinical studies targeting K-ras directly or indirectly via its downstream signal transduction machinery will be discussed. Additionally, some of the challenges and limitations of various K-ras targeting immunotherapeutic approaches such as vaccines, adoptive T cell therapies, and checkpoint inhibitors against KRAS positive cancers will be deliberated.

Antitumor effect of proanthocyanidin induced apoptosis in human colorectal cancer (HT-29) cells and its molecular docking studies

Proanthocyanidin (PAC) is a promising compound that has displayed its potent antineoplastic properties with a specific intrinsic pathway. This precise us to explore the phyto-preventive effect of PAC against colon cancer (HT-29). The results showed that PAC inhibited the cell growth and GI50 value was found to be 6.25 μM for 24 h exposure, when correlated to the normal cell line does not have toxicity was noticed. The linguistic differences, similarly membrane blebbing, cell shrinkage fragmented nuclear bodies and mitochondrial membrane were observed in AO/EtBr and DAPI staining. The features of regular mechanical apoptotic characterization was analyzed by DNA fragmentation. The cell cycle arrest at G2/M phases was detected using FACS analysis. The early and late apoptotic cells were observed by using Annexin V/PI staining. The ligand-protein interaction and docking studies were performed using Schrodinger's software. The QPLD analysis of docking studies revealed that PAC exhibited better binding affinity of - 5.23, - 5.17 and - 4.43, - 4.47 kcal/mol against BCL-XL, CDK2 and were compared with 5-FU respectively, which significantly reveals the anticancerous activity of Proanthocyanidin compound. Thus, the PAC compound provides future application of therapeutic option in the treatment of colon cancers.

Plasma microRNA Levels Combined with CEA and CA19-9 in the Follow-Up of Colorectal Cancer Patients

Colorectal cancer (CRC) ranks among the most common cancers worldwide. Surgical removal remains the best strategy for treatment of resectable tumors. An important part of caring for patients after surgery is monitoring for early detection of a possible relapse of the disease. Efforts are being made to improve the sensitivity and specificity of routinely used carcinoembryonic antigen (CEA) with the use of additional biomarkers such as microRNAs. The aim of our study was to evaluate the prognostic potential of microRNAs and their use as markers of disease recurrence. The quantitative estimation of CEA, CA19-9, and 22 selected microRNAs (TaqMan Advanced miRNA Assays) was performed in 85 paired (preoperative and postoperative) blood plasma samples of CRC patients and in samples taken during the follow-up period. We have revealed a statistically significant decrease in plasma levels for miR-20a, miR-23a, miR-210, and miR-223a (p = 0.0093, p = 0.0013, p = 0.0392, and p = 0.0214, respectively) after surgical removal of the tumor tissue. A statistically significant relation to prognosis (overall survival; OS) was recorded for preoperative plasma levels of miR-20a, miR-21, and miR-23a (p = 0.0236, p = 0.0316, and p =0.0271, respectively) in a subgroup of patients who underwent palliative surgery. The best discrimination between patients with favorable and unfavorable outcomes was achieved by a combination of CEA, CA19-9 with miR-21, miR-20a, and miR-23a (p < 0.0001). The use of these microRNAs for early disease recurrence detection was affected by a low specificity in comparison with CEA and CA19-9. CEA and CA19-9 had high specificity but low sensitivity. Our results show the benefit of combining currently used standard biomarkers and microRNAs for precise prognosis estimation.

Effect of fibroblast co-culture on the proliferation, viability and drug response of colon cancer cells

Interactions between cancer cells and the surrounding fibroblasts serve an important role in cancer proliferation. Colon cancer co-culture model with colon fibroblasts and two metastatic models with lung and skin fibroblasts were established, and the co-culture effects on colon cancer cell proliferation, apoptosis and drug response were evaluated. Co-culture with CCD-18Co and BJ reduces SW480 cell proliferation by 4.2 and 5.3%, respectively, while WI-38 acts as a positive regulator and increases SW480 cell proliferation by 36%. CCD-18Co and BJ co-culture can also enhance XAV939 potency against SW480 cells by 16.8 and 27.3%; however, WI-38 co-culture reduces the effect of XAV939 by 38.2%. The present results suggest that, depending on fibroblast type, co-culture can have a positive/negative influence on colon cancer growth; therefore, care should be taken when considering fibroblasts as a target for future cancer therapies.

Dichloroacetate and Salinomycin Exert a Synergistic Cytotoxic Effect in Colorectal Cancer Cell Lines

In the present study, we examined a hypothesis that dichloroacetate, a metabolic inhibitor, might efficiently potentiate the cytotoxic effect of salinomycin, an antibiotic ionophore, on two human colorectal cancer derived cell lines DLD-1 and HCT116. First, we performed a series of dose response experiments in the 2D cell culture by applying mono- and combination therapy and by using the Chou-Talalay method found that salinomycin in combination with dichloroacetate acted synergistically in both cell lines. Secondly, in order to recapitulate the in vivo tumor architecture, we tested various doses of these compounds, alone and in combination, in the 3D multicellular spheroid culture. The effect of combination of dichloracetate and salinomycin on multicellular spheroid size was stronger than the sum of both monotherapies, particularly in HCT116 cells. Further, we demonstrate that the synergistic effect of compounds may be related to the inhibitory effect of dichloroacetate on multidrug resistance proteins, and in contrast, it is not related to dichloroacetate-induced reduction of intracellular pH. Our findings indicate that the combination therapy of salinomycin and dichloroacetate could be an effective option for colorectal cancer treatment and provide the first mechanistic explanation of the synergistic action of these compounds.

P4HB knockdown induces human HT29 colon cancer cell apoptosis through the generation of reactive oxygen species and inactivation of STAT3 signaling

Colon cancer is the second most lethal malignancy worldwide. A better understanding of colon cancer at the molecular level may increase overall survival rates. Previous studies have indicated that prolyl 4-hydroxylase, β polypeptide (P4HB) is associated with tumorigenesis in colon cancer; however, its role and molecular mechanisms in colon cancer remain unclear. In the present study, the cellular responses to P4HB in human colon cancer cell lines were investigated by proliferation and apoptosis assays, western blotting, and immunohistochemistry. The results showed that expression of P4HB was higher in colon cancer tissues compared within adjacent normal tissues. P4HB knockdown increased the apoptosis of human HT29 cells. Furthermore, P4HB knockdown reduced the activation of signal transducer and activator of transcription 3 (STAT3) and promoted accumulation of reactive oxygen species (ROS). Inhibiting the accumulation of ROS abrogated the increased cell apoptosis induced by P4HB knockdown. Notably, decreased ROS levels effectively antagonized the effects of P4HB on STAT3 inactivation. In conclusion, these findings suggested that P4HB knockdown may induce HT29 human colon cancer cell apoptosis through the generation of ROS and inactivation of the STAT3 signaling pathway.

A New Fight Against Colon Cancer: As Cancer Rates Rise Among Younger Adults, Researchers Look for New Screening and Treatment Options

Although the overall incidence of colon cancer has been falling over the past few decades, a pair of recent studies revealed a startling trend. In February 2017, researchers published a report showing that colon cancer rates were rising among younger adults. Some skeptics suggested the spike might simply reflect earlier detection and not necessarily represent a real increase in the disease. But a follow-up study found that Gen-Xers and millenials aren't just getting cancer diagnoses earlier; they are dying from colon cancer at slightly higher rates than in previous decades. Death rates among adults aged 20-54 have increased slightly, to 4.3 deaths per 100,000 people in 2014, up from 3.9 per 100,000 in 2004.

Correlation of immunohistochemical mismatch repair protein status between colorectal carcinoma endoscopic biopsy and resection specimens

Background

Microsatellite instability is reflective of a deficient mismatch repair system (dMMR), which may be due to either sporadic or germline mutations in the relevant mismatch repair (MMR) gene. MMR status is frequently determined by immunohistochemistry (IHC) for mismatch repair proteins (MMRPs) on colorectal cancer (CRC) resection specimens. However, IHC testing performed on endoscopic biopsy may be as reliable as that performed on surgical resections.

Aim

We aimed to evaluate the reliability of MMR IHC staining on preoperative CRC endoscopic biopsies compared with matched-surgical resection specimens.

Methods

A retrospective search of our institution’s histopathology electronic database was performed. Patients with CRC who had MMR IHC performed on both their preoperative endoscopic biopsy and subsequent resection from January 2010 to January 2016 were included. Concordance of MMR staining between biopsy and resection specimens was assessed.

Results

From 2000 to 2016, 53 patients had MMR IHC performed on both their preoperative colorectal endoscopic biopsy and resection specimens; 10 patients (18.87%) demonstrated loss of ≥1 MMRP on their initial endoscopic tumour biopsy. The remainder (81.13%) showed preservation of staining for all MMRPs. There was complete agreement in MMR IHC status between the preoperative endoscopic biopsies and corresponding resection specimens in all cases (κ=1.000, P<0.000) with a sensitivity of 100% (95% CI 69.15 to 100) and specificity of 100% (95% CI 91.78 to 100) for detection of dMMR.

Conclusion

Endoscopic biopsies are a suitable source of tissue for MMR IHC analysis. This may provide a number of advantages to both patients and clinicians in the management of CRC.

Proapoptotic and Antimigratory Effects of Pseudevernia furfuracea and Platismatia glauca on Colon Cancer Cell Lines

The aim of this study is to investigate cytotoxic, proapoptotic, antimigratory and pro-antioxidant effects of methanol, acetone and ethyl acetate extracts of lichens Pseudevernia furfuracea and Platismatia glauca on colorectal cancer (HCT-116 and SW-480) cell lines. We compared the cytotoxic effects on colorectal cancer cells with the effects obtained from normal human fibroblast (MRC-5) cell line. Tetrazolium (MTT) test evaluated the cytotoxic effects, Transwell assay evaluated cell migration, acridine orange/ethidium bromide (AO/EB) fluorescent method followed the apoptosis, while prooxidant/antioxidant effects were determined spectrophotometrically through concentration of redox parameters. The tested extracts showed considerable cytotoxic effect on cancer cells with no observable cytotoxic effect on normal cells. Ethyl acetate and acetone extract of P. furfuracea induced the highest cytotoxicity (IC₅₀=(21.2±1.3) µg/mL on HCT-116, and IC₅₀=(51.3±0.8) µg/mL on SW-480 cells, respectively, after 72 h), with noteworthy apoptotic and prooxidant effects, and antimigratory potential of methanol extract. P. glauca extracts induced cytotoxic effects on HCT-116 cells after 72 h (IC₅₀<40 μg/mL), while only methanol and acetone extracts had cytotoxic effects on SW-480 cells after 24 h, with proapoptotic/necrotic activity, as a consequence of induced oxidative stress. In conclusion, lichen extracts changed to a great extent cell viability and migratory potential of colorectal cancer cell lines. HCT-116 cells were more sensitive to treatments, P. furfuracea had better proapoptotic and antimigratory effects, and both investigated lichen species might be a source of substances with anticancer activity.

Unraveling the human protein atlas of metastatic melanoma in the course of ultraviolet radiation-derived photo-therapy

To explore the photo-therapeutic capacity of UV radiation in solid tumors, we herein employed an nLC-MS/MS technology to profile the proteomic landscape of irradiated WM-266-4 human metastatic-melanoma cells. Obtained data resulted in proteomic catalogues of 5982 and 7280 proteins for UVB- and UVC-radiation conditions, respectively, and indicated the ability of UVB/C-radiation forms to eliminate metastatic-melanoma cells through induction of synergistically operating programs of apoptosis and necroptosis. However, it seems that one or more WM-266-4 cell sub-populations may escape from UV-radiation's photo-damaging activity, acquiring, besides apoptosis tolerance, an EMT phenotype that likely offers them the advantage of developing resistance to certain chemotherapeutic drugs. Low levels of autophagy may also critically contribute to the selective survival and growth of UV-irradiated melanoma-cell escapers. These are the cells that must be systemically targeted with novel therapeutic schemes, like the one of UV radiation and Irinotecan herein suggested to be holding strong promise for the effective treatment of metastatic-melanoma patients. Given the dual nature of UV radiation to serve as both anti-tumorigenic and tumorigenic agent, all individuals being subjected to risk factors for melanoma development have to be appropriately informed and educated, in order to integrate the innovative PPPM concept in their healthcare-sector management.

SIGNIFICANCE

This study reports the application of nLC-MS/MS technology to deeply map the proteomic landscape of UV-irradiated human metastatic-melanoma cells. Data bioinformatics processing led to molecular-network reconstructions that unearthed the dual nature of UV radiation to serve as both anti-tumorigenic and tumorigenic factor in metastatic-melanoma cellular environments. Our UV radiation-derived "photo-proteomic" atlas may prove valuable for the identification of new biomarkers and development of novel therapies for the disease. Given that UV radiation represents a major risk factor causing melanoma, a PPPM-based life style and clinical practice must be embraced by all individuals being prone to disease's appearance and expansion.

Targeted photodynamic therapy as potential treatment modality for the eradication of colon cancer and colon cancer stem cells

Colorectal cancer is commonly treated by tumour resection, as chemotherapy and radiation have proven to be less effective, especially if the tumour has metastasized. Resistance to therapies occurs in almost all patients with colorectal cancer, especially in those with metastatic tumours. Cancer stem cells have the ability to self-renew, and their slow rate of cycling enhances resistance to treatment and increases the likelihood of tumour recurrence. Most metastatic tumours are unable to be surgically removed, thus creating a need for treatment modalities that target cancers directly and destroy cancer stem cells. Photodynamic therapy involves a photosensitizer that when exposed to a light source of a particular wavelength becomes excited and produces a form of oxygen that kills cancer cells. Photodynamic therapy is currently being investigated as a treatment modality for colorectal cancer, and new studies are exploring enhancing photodynamic therapy efficacy with the aid of drug carriers and immune conjugates. These modifications could prove effective in targeting cancer stem cells that are thought to be resistant to photodynamic therapy. In order for photodynamic therapy to be an effective treatment in colorectal cancer, it requires treatment of both primary tumours and the metastatic secondary disease that is caused by colon cancer stem cells. This review focuses on current photodynamic therapy treatments available for colorectal cancer and highlights proposed actively targeted photosynthetic drug uptake mechanisms specifically mediated towards colon cancer stem cells, as well as identify the gaps in research which need to be investigated in order to develop a combinative targeted photodynamic therapy regime that can effectively control colorectal cancer primary and metastatic tumour growth by eliminating colon cancer stem cells.

Towards personalized medicine of colorectal cancer

Efforts in colorectal cancer (CRC) research aim to improve early detection and treatment for metastatic stages which could translate into better prognosis of this disease. One of the major challenges that hinder these efforts is the heterogeneous nature of CRC and involvement of diverse molecular pathways. New large-scale 'omics' technologies are making it possible to generate, analyze and interpret biological data from molecular determinants of CRC. The developments of sophisticated computational analyses would allow information from different omics platforms to be integrated, thus providing new insights into the biology of CRC. Together, these technological advances and an improved mechanistic understanding might allow CRC to be clinically managed at the level of the individual patient. This review provides an account of the current challenges in CRC management and an insight into how new technologies could allow the development of personalized medicine for CRC.

Molecular Characterization of Somatic Alterations in Dukes' B and C Colorectal Cancers by Targeted Sequencing

Despite global progress in research, improved screening and refined treatment strategies, colorectal cancer (CRC) remains as the third most common malignancy. As each type of cancer is different and exhibits unique alteration patterns, identifying and characterizing gene alterations in CRC that may serve as biomarkers might help to improve diagnosis, prognosis and predict potential response to therapy. With the emergence of next generation sequencing technologies (NGS), it is now possible to extensively and rapidly identify the gene profile of individual tumors. In this study, we aimed to identify actionable somatic alterations in Dukes’ B and C in CRC via NGS. Targeted sequencing of 409 cancer-related genes using the Ion Ampliseq^TM Comprehensive Cancer Panel was performed on genomic DNA obtained from paired fresh frozen tissues, cancer and normal, of Dukes’ B (n = 10) and Dukes’ C (n = 9) CRC. The sequencing results were analyzed using Torrent Suite, annotated using ANNOVAR and validated using Sanger sequencing. A total of 141 somatic non-synonymous sequence variations were identified in 86 genes. Among these, 64 variants (45%) were predicted to be deleterious, 38 variants (27%) possibly deleterious while the other 39 variants (28%) have low or neutral protein impact. Seventeen genes have alterations with frequencies of ≥10% in the patient cohort and with 14 overlapped genes in both Dukes’ B and C. The adenomatous polyposis coli gene (APC) was the most frequently altered gene in both groups (n = 6 in Dukes’ B and C). In addition, TP53 was more frequently altered in Dukes’ C (n = 7) compared to Dukes’ B (n = 4). Ten variants in APC, namely p.R283^∗, p.N778fs, p.R805^∗, p.Y935fs, p.E941fs, p.E1057^∗, p.I1401fs, p.Q1378^∗, p.E1379^∗, and p.A1485fs were predicted to be driver variants. APC remains as the most frequently altered gene in the intermediate stages of CRC. Wnt signaling pathway is the major affected pathway followed by P53, RAS, TGF-β, and PI3K signaling. We reported the alteration profiles in each of the patient which has the potential to affect the clinical decision. We believe that this study will add further to the understanding of CRC molecular landscape.

The current value of determining the mismatch repair status of colorectal cancer: A rationale for routine testing

Colorectal Cancer (CRC) is the third most prevalent cancer in men and women. Up to 15% of CRCs display microsatellite instability (MSI). MSI is reflective of a deficient mismatch repair (MMR) system and is most commonly caused by hypermethylation of the MLH1 promoter. However, it may also be due to autosomal dominant constitutional mutations in DNA MMR, termed Lynch Syndrome. MSI may be diagnosed via polymerase chain reaction (PCR) or alternatively, immunohistochemistry (IHC) can identify MMR deficiency (dMMR). Many institutions now advocate universal tumor screening of CRC via either PCR for MSI or IHC for dMMR to guide Lynch Syndrome testing. The association of sporadic MSI with methylation of the MLH1 promoter and an activating BRAF mutation may offer further exclusion criteria for genetic testing. Aside from screening for Lynch syndrome, MMR testing is important because of its prognostic and therapeutic implications. Several studies have shown MSI CRCs exhibit different clinicopathological features and prognosis compared to microsatellite-stable (MSS) CRCs. For example, response to conventional chemotherapy has been reported to be less in MSI tumours. More recently, MSI tumours have been shown to be responsive to immune-checkpoint inhibition providing a novel therapeutic strategy. This provides a rationale for routine testing for MSI or dMMR in CRC.

MicroRNA-645 is an oncogenic regulator in colon cancer

Despite advances in early diagnosis and the development of molecularly targeted therapy, curative treatment of colon cancer once it has metastasized is yet to be accomplished. This is closely associated with deregulated CRC cell proliferation and resistance to apoptosis. Here we reveal that upregulation of microRNA-645 (miR-645) through DNA copy number gain is responsible for enhanced proliferation and resistance to apoptosis in colon cancer. MiR-645 was upregulated in most colon cancer tissues related to adjacent normal mucosa. This appeared to be associated with amplification of a section of chromosome 20q13.13, where miR-645 is located. Inhibition of miR-645 reduced proliferation and enhanced sensitivity to apoptosis triggered by the chemotherapeutic drugs 5-fluorouracil and cisplatin in CRC cells, and retarded colon cancer xenograft growth. Conversely, overexpression of miR-645 in normal colon epithelial cells enhanced proliferation and triggered anchorage-independent cell growth. Although SRY-related HMG-box 30 (SOX30) was identified as a miR-645 target, its expression was only partially affected by miR-645, suggesting that miR-645 is a fine-tuning mechanism of SOX30 expression. Moreover, overexpression of SOX30 only moderately inhibited promotion of CRC cell proliferation by miR-645, indicating that miR-645 may have more targets that contribute to its pro-proliferation effect in colon cancer. Together, this study reveals that miR-645 can regulate oncogenesis in colon cancer with SOX30 being one of its targets.

Leucovorin Enhances the Anti-cancer Effect of Bortezomib in Colorectal Cancer Cells

Colorectal cancer is a major cancer type worldwide. 5-fluorouracil, often given with leucovorin, is the most commonly used drug in colorectal cancer chemotherapy, yet development of drug resistance to 5-fluorouracil in colorectal cancer cells is the primary cause of chemotherapy failure. Most patients receiving intravenous 5-fluorouracil develop side effects. Leucovorin, due to its vitamin-like profile, has few side-effects. Drug repurposing is the application of approved drugs to treat new indications. In this study, we performed a novel drug-repurposing screening to identify Food and Drug Administration-approved chemotherapeutic compounds possessing synergistic activity with leucovorin against colorectal cancer cells. We found that the combination of bortezomib and leucovorin enhanced caspase activation and increased apoptosis in colorectal cancer cells better than either agent alone. Further, the synergistic induction of apoptosis and inhibition of tumor growth were also observed in mouse colorectal cancer xenografts. These data support leucovorin enhances the anti-cancer effect of bortezomib and present this novel combinatorial treatment against colorectal cancer.

HDAC inhibitors show differential epigenetic regulation and cell survival strategies on p53 mutant colon cancer cells

Besides inactivating tumour suppressor activity in cells, mutations in p53 confer significant oncogenic functions and promote metastasis and resistance to anticancer therapy. A variety of therapies involving genetic and epigenetic signalling events regulate tumorogenesis and progression in such cases. Pharmacological interventions with HDAC inhibitors have shown promise in therapy. This work explores the changes in efficacy of the four HDAC inhibitors SAHA, MS-275, valproic acid and sodium butyrate on a panel of colon cancer cell lines - HCT116 (p53 wt), HCT116 p53-/-, HT29 and SW480 (with mutations in p53). Clonogenic assays, gene profiling and epigenetic expression done on these cells point to p53 dependent differential activity of the 4 HDAC inhibitors which also elevate methylation levels in p53 mutant cell lines. In silico modelling establishes the alterations in interactions that lead to such differential activity of valproic acid, one of the inhibitors considered for the work. Molecular Dynamic simulations carried out on the valproic acid complex ensure stability of the complex. This work establishes a p53 dependent epigenetic signalling mechanism triggered by HDAC inhibition expanding the scope of HDAC inhibitors in adjuvant therapy for p53 mutant tumours.

Targeting MUC1-C inhibits the AKT-S6K1-elF4A pathway regulating TIGAR translation in colorectal cancer

Background

Colorectal cancer is third most common malignancy and is the second most common cause of cancer-related death. The MUC1 heterodimeric protein is aberrantly overexpressed in colorectal cancer and has been linked to poor outcomes in this disease. Here, we investigate the effects of the MUC1-C subunit inhibitor (GO-203), which disrupts MUC1-C homo-oligomerization, on human colorectal cancer cells.

Methods

TIGAR mRNA level was determined using qRT-PCR. Western blotting was used to measure TIGAR protein level and AKT-mTOR-S6K1 pathways. Reactive oxygen species and apoptosis were measured by flow cytometry. Effect of MUC1-C peptide, GO-203 was studied on colorectal xenograft tumors. Immunohistochemistry was utilized for TIGAR staining.

Results

Treatment of MUC1-overexpressing SKCO-1 and Colo-205 colon cancer cells with GO-203 was associated with downregulation of the TP53-inducible glycolysis and apoptosis regulator (TIGAR) protein. TIGAR promotes the shunting of glycolytic intermediates into the pentose phosphate pathway and thus is of importance for maintaining redox balance. We show that GO-203-induced suppression of TIGAR is mediated by inhibition of AKT and the downstream mTOR pathway. The results also demonstrate that targeting MUC1-C blocks eIF4A cap-dependent translation of TIGAR. In concert with these results, GO-203-induced suppression of TIGAR was associated with decreases in GSH levels. GO-203 treatment also resulted in increases in reactive oxygen species (ROS) and loss of mitochondrial transmembrane potential. Consistent with these results, GO-203 inhibited the growth of colon cancer cells in vitro and as xenografts in nude mice. Inhibition of MUC1-C also downregulated TIGAR expression in xenograft tissues.

Conclusions

These findings indicate that MUC1-C is a potential target for the treatment of colorectal cancer. Colorectal cancer patients who overexpress MUC1-C may be candidates for treatment with the MUC1-C inhibitor alone or in combination therapy with other agents.

Tumor suppressor genes in familial adenomatous polyposis

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

Lupane-type triterpenes and their anti-cancer activities against most common malignant tumors: A review

In recent times, a great deal of interest has been motivated on plant derived compounds known as nutraceuticals. These compounds exert important beneficial activities that improve people's health status when are consumed regularly, and now they appear as a viable option to explore their possible therapeutic effects against diseases like cancer. Particularly, lupane-type triterpenes have shown great ability to modulate multiple cancer-related signaling pathways and processes, including NF-κB, Wnt/β-catenin, PI3K/Akt, apoptosis, and many other routes related to proliferation or cell death, which are uncontrolled in malignant tumors. These investigations have promoted in vitro and in vivo studies, searching their mechanisms of action; although more research is still needed to prove its potential in human clinical trials. This review focuses on the ability of betulin, betulinic acid and lupeol to show benefits against the most common types of malignant tumors, which are considered a major global threat for public health.

Bone morphogenetic protein 2 (BMP2) induces growth suppression and enhances chemosensitivity of human colon cancer cells

BACKGROUND

Molecular profiling of colorectal cancer (CRC) based on global gene expression has revealed multiple dysregulated signalling pathways associated with drug resistance and poor prognosis. However, the role of BMP2 signaling in CRC is not fully characterised.

METHODS

Bioinformatics data analysis were conducted on the GSE21510 dataset. Leniviral technology was utilized to stably express BMP2 in the HCT116 CRC model. Gene expression profiling was conducted using Agilent microarray platform while data normalization and bioinformatics were conducted using GeneSpring software. Changes in gene expression were assessed using qRT-PCR. AlamarBlue assay was used to assess cell viability in vitro. In vivo experiments were conducted using SCID mice.

RESULTS

Our data revealed frequent downregulation of BMP2 in primary CRC tissues. Additionally, interrogation of publically available gene expression datasets revealed significant downregulation of BMP2 in metastatic recurrent compared to non-metastatic cancer (p = 0.02). Global gene expression analysis in CRC cells over-expressing BMP2 revealed multiple dysregulated pathways mostly affecting cell cycle and DNA damage response. Concordantly, lentiviral-mediated re-expression of BMP2 inhibited HCT116 CRC growth, sphere formation, clonogenic potential, cell migration, and sensitized CRC cells to 5-fluorouracil (5-FU) in vitro. Additionally, BMP2 inhibited CRC tumor formation in SCID mice.

CONCLUSIONS

Our data revealed an inhibitory role for BMP2 in CRC, suggesting that restoration of BMP2 expression could be a potential therapeutic strategy for CRC.

Tear fluid biomarkers in ocular and systemic disease: potential use for predictive, preventive and personalised medicine

In the field of predictive, preventive and personalised medicine, researchers are keen to identify novel and reliable ways to predict and diagnose disease, as well as to monitor patient response to therapeutic agents. In the last decade alone, the sensitivity of profiling technologies has undergone huge improvements in detection sensitivity, thus allowing quantification of minute samples, for example body fluids that were previously difficult to assay. As a consequence, there has been a huge increase in tear fluid investigation, predominantly in the field of ocular surface disease. As tears are a more accessible and less complex body fluid (than serum or plasma) and sampling is much less invasive, research is starting to focus on how disease processes affect the proteomic, lipidomic and metabolomic composition of the tear film. By determining compositional changes to tear profiles, crucial pathways in disease progression may be identified, allowing for more predictive and personalised therapy of the individual. This article will provide an overview of the various putative tear fluid biomarkers that have been identified to date, ranging from ocular surface disease and retinopathies to cancer and multiple sclerosis. Putative tear fluid biomarkers of ocular disorders, as well as the more recent field of systemic disease biomarkers, will be shown.

FAT1: a potential target for monoclonal antibody therapy in colon cancer

Background:

Colorectal cancer (CRC) is one of the major causes of cancer-associated mortality worldwide. The currently approved therapeutic agents have limited efficacy.

Methods:

The atypical cadherin FAT1 was discovered as a novel CRC-associated protein by using a monoclonal antibody (mAb198.3). FAT1 expression was assessed in CRC cells by immunohistochemistry (IHC), immunoblots, flow cytometry and confocal microscopy. In addition, in vitro and in vivo tumour models were done to assess FAT1 potential value for therapeutic applications.

Results:

The study shows that FAT1 is broadly expressed in primary and metastatic CRC stages and detected by mAb198.3, regardless of KRAS and BRAF mutations. FAT1 mainly accumulates at the plasma membrane of cancer cells, whereas it is only marginally detected in normal human samples. Moreover, the study shows that FAT1 has an important role in cell invasiveness while it does not significantly influence apoptosis. mAb198.3 specifically recognises FAT1 on the surface of colon cancer cells and is efficiently internalised. Furthermore, it reduces cancer growth in a colon cancer xenograft model.

Conclusions:

This study provides evidence that FAT1 and mAb198.3 may offer new therapeutic opportunities for CRC including the tumours resistant to current EGFR-targeted therapies.

miR‑410 regulates apoptosis by targeting Bak1 in human colorectal cancer cells

MicroRNAs (miRs) are essential in the pathogenesis of colorectal cancer (CRC). Previous studies have demonstrated that miR‑410 exerts multiple effects on tumors, however, whether it affects the apoptosis of CRC cells remains to be elucidated. In the present study, to demonstrate the role of miR-410 in CRC, miR-410 expression was detected in CRC tissues and cell lines, and the miR-410 level was manipulated by transfection with an miR-410 or miR-410 inhibitor in CRC cells. Cell growth and apoptosis was tested using an MTT assay, western blot and cytochrome C assay. Target validation was conducted by luciferase assay. It was found that miR‑410 was upregulated in CRC tissues and cell lines. The overexpression of miR‑410 resulted in an increase in growth activity and decrease in the extent of apoptosis. By contrast, the inhibition of endogenous miR‑410 activated the apoptotic machinery. Western blot analysis and a luciferase activity assay showed that Bak1 was directly targeted by miR‑410, and that knockdown of Bak1 attenuated the pro‑apoptotic effect of miR‑410 inhibition. In addition, it was shown that the expression of Bak1 was downregulated in CRC tumor tissues and was reversely correlated with the expression of miR‑410, which provided further support that Bak1 was regulated by miR‑410. The results of the present study suggested that miR‑410 may function as an oncogenic miR by suppressing the basal level of apoptosis. These findings may assist in understanding the molecular mechanisms of cancer development.

Markers of Response to Antiangiogenic Therapies in Colorectal Cancer: Where Are We Now and What Should Be Next?

Despite advances in the treatment of colorectal cancer (CRC), it remains the second most common cause of cancer-related death in the Western world. Angiogenesis is a complex process that involves the formation of new blood vessels from preexisting vessels. It is essential for promoting cancer survival, growth, and dissemination. The inhibition of angiogenesis has been shown to prevent tumor progression experimentally, and several chemotherapeutic targets of tumor angiogenesis have been identified. These include anti-vascular endothelial growth factor (VEGF) treatments, such as bevacizumab (a VEGF-specific binding antibody) and anti-VEGF receptor tyrosine kinase inhibitors, although antiangiogenic therapy has been shown to be effective in the treatment of several cancers, including CRC. However, it is also associated with its own side effects and financial costs. Therefore, the identification of biomarkers that are able to identify patients who are more likely to benefit from antiangiogenic treatment is very important. This article intends to be a concise summary of the potential biomarkers that can predict or prognosticate the benefit of antiangiogenic treatments in CRC, and also what we can expect in the near future.

Anaplastic thyroid carcinoma: Failure of conventional therapy but hope of targeted therapy

BACKGROUND

Anaplastic thyroid cancer has a median survival between 1.2 and 10 months. The purpose of our study was to evaluate the outcomes of patients with anaplastic thyroid cancer in Ireland.

METHODS

We carried out a retrospective analysis of the Irish National Cancer Database for patients with anaplastic thyroid cancer between 2000 and 2010.

RESULTS

Of a total of 64 patients (40 women, 24 men), the median age was 69 years, and 29.7% of the patients had distant metastases. The overall median survival was 2.3 months and the 1, 2, and 5-year survival was 12.5%, 6.25%, and 4.69%, respectively. On univariate analysis age, sex, metastases at diagnosis, and multimodality treatment were statistically significant indicators of prognosis, and metastases at diagnosis remained statistically significant on multivariate analysis.

CONCLUSION

These results correlate with the American Thyroid Association (ATA) guidelines, in which, when possible, multimodality therapy offers a survival advantage to a select group of patients. Novel therapies may offer the greatest hope for these patients. © 2016 Wiley Periodicals, Inc. Head Neck 38: E1122-E1129, 2016.

Targeting EGFR in metastatic colorectal cancer beyond the limitations of KRAS status: alternative biomarkers and therapeutic strategies

Patients with metastatic colorectal cancer have a very poor prognosis. Incorporation of targeted molecular therapies, such as the anti-EGFR receptor monoclonal antibodies cetuximab and panitumumab, into treatment regimens has improved outcomes for patients with wild-type RAS tumors. Yet, response rates remain low and overall survival times are short. Increased understanding of oncogenic signaling pathways within the tumor, and how these are regulated by the inflammatory tumor microenvironment, is a priority to facilitate the development of biomarkers to better guide the use of existing therapies and to develop new ones. Here, we review recent preclinical and clinical progress in the development of biomarkers for predicting response to anti-EGFR therapy in metastatic colorectal cancer.

EPMA position paper in cancer: current overview and future perspectives

At present, a radical shift in cancer treatment is occurring in terms of predictive, preventive, and personalized medicine (PPPM). Individual patients will participate in more aspects of their healthcare. During the development of PPPM, many rapid, specific, and sensitive new methods for earlier detection of cancer will result in more efficient management of the patient and hence a better quality of life. Coordination of the various activities among different healthcare professionals in primary, secondary, and tertiary care requires well-defined competencies, implementation of training and educational programs, sharing of data, and harmonized guidelines. In this position paper, the current knowledge to understand cancer predisposition and risk factors, the cellular biology of cancer, predictive markers and treatment outcome, the improvement in technologies in screening and diagnosis, and provision of better drug development solutions are discussed in the context of a better implementation of personalized medicine. Recognition of the major risk factors for cancer initiation is the key for preventive strategies (EPMA J. 4(1):6, 2013). Of interest, cancer predisposing syndromes in particular the monogenic subtypes that lead to cancer progression are well defined and one should focus on implementation strategies to identify individuals at risk to allow preventive measures and early screening/diagnosis. Implementation of such measures is disturbed by improper use of the data, with breach of data protection as one of the risks to be heavily controlled. Population screening requires in depth cost-benefit analysis to justify healthcare costs, and the parameters screened should provide information that allow an actionable and deliverable solution, for better healthcare provision.

Nanocrystalline cerium dioxide efficacy for gastrointestinal motility: potential for prokinetic treatment and prevention in elderly

BACKGROUND

Constipation is a common condition, with prevalence after 65 years, is a major colorectal cancer risk factor. Recent works have demonstrated advances in personalized, preventive nanomedicine, leading to the construction of new materials and nanodrugs, in particular, nanocrystalline cerium dioxide (NCD), having strong antioxidative prebiotic effect. The aim of our study was to investigate the influence of NCD on motor function of the stomach and colon in vivo and contractive activity of smooth muscles in different year-old rats.

METHODS

We included 80 rats: 3- (weight 130-160 g, n = 40) and 24-month old (weight 390-450 g, n = 40), divided into four groups as follows: І-control group; rats of II-ІV groups were injected intragastrically one injection per day during 10 days, 3 ml of water 3 ml/kg stabilizing solution, аnd 1 mmol/ml NCD, respectively. In all animals, we recorded spontaneous and carbachol-stimulated (0.01 mg/kg) gastrointestinal tract motor activity. We used the index of motor activity (IMA), expressed in cmH2O, for characterization of the motor function. We investigated smooth muscle contraction by tenzometric method, studied the spontaneous and stimulated motility by ballonographic method.

RESULTS

IMA reduced by 21.1 + 0.2% (p < 0.01) in the old rats of the control group compared with the young rats. A 10-day administration of NCD increased IMA in the stomach of young rats by 9.3% (р < 0.001) vs the control group. The exposure of NCD increased the amplitude of contraction to 34.2 ± 5.4 mN (n = 10) in the stomach of old rats and increased by 32.1 ± 2.4% vs the control group (p < 0.05). NCD did not influence acetylcholine (ACh) contractions in the stomach of young rats; however, in the stomach of old rats, V nr increased by 90 ± 15.2% (р < 0.001).

CONCLUSIONS

The index of motor activity is decreased in old rats. Nanocrystalline cerium dioxide increased the index of motor activity in all groups of rats and also evoked a significant increase of colon contractions in old rats.

Mutant KRAS as a critical determinant of the therapeutic response of colorectal cancer

Mutations in the KRAS oncogene represent one of the most prevalent genetic alterations in colorectal cancer (CRC), the third leading cause of cancer-related death in the US. In addition to their well-characterized function in driving tumor progression, KRAS mutations have been recognized as a critical determinant of the therapeutic response of CRC. Recent studies demonstrate that KRAS-mutant tumors are intrinsically insensitive to clinically-used epidermal growth factor receptor (EGFR) targeting antibodies, including cetuximab and panitumumab. Acquired resistance to the anti-EGFR therapy was found to be associated with enrichment of KRAS-mutant tumor cells. However, the underlying molecular mechanism of mutant-KRAS-mediated therapeutic resistance has remained unclear. Despite intensive efforts, directly targeting mutant KRAS has been largely unsuccessful. This review summarizes the recent advances in understanding the biological function of KRAS mutations in determining the therapeutic response of CRC, highlighting several recently developed agents and strategies for targeting mutant KRAS, such as synthetic lethal interactions.