Current approaches and challenges for monitoring treatment response in colon and rectal cancer

The diagnostic value of serum Ephrin-A1 in patients with colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide, with a high incidence rate and mortality. The analysis of serum biomarkers for colorectal cancer diagnosis has attracted more and more attention because of its low cost, repeatability, and quantification. This study was aimed to evaluate the diagnostic performance of serum Ephrin-A1 in patients with CRC. We retrospectively analyzed CRC cases in a test cohort (121 patients and 108 controls) and validated them in a validation cohort (119 patients and 118 controls). The concentration of Ephrin-A1 in serum was detected by Enzyme-linked immunosorbent assay (ELISA) and the diagnostic performance of serum Ephrin-A1 was evaluated by receiver operating characteristic (ROC) analysis. In the test cohort, serum Ephrin-A1 levels in patients with all-stage CRC and early-stage CRC were significantly higher than those in healthy controls. The area under the ROC curve (AUC), sensitivity and specificity of all-stage CRC and early-stage CRC were 0.709 (95% CI 0.644-0.775) and 0.660 (95% CI 0.530-0.790), 48.76% and 45.00%, 81.48% and 81.48%, respectively. Similar results were observed in the validation cohort. Serum Ephrin-A1 might be served as a potential biomarker in the diagnosis of CRC.

A retrospective study comparing the efficacy of microwave ablation and stereotactic body radiotherapy in colorectal cancer lung metastases

The purpose of the present study was to assess and compare the efficacy of microwave ablation (MWA) and stereotactic body radiotherapy (SBRT) in the treatment of lung metastases from patients with colorectal cancer (CRC) and to identify the preferable treatment modality based on patient and tumor characteristics. Records of 118 patients with CRC with a total of 307 lung metastases who underwent SBRT or MWA between January 2015 and December 2022 were retrospectively analyzed, including the essential clinicopathological information on patients (age, sex and underlying diseases), diagnosis and treatment information [primary tumor site, levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9], imaging data [diameter of lung metastasis, location of the metastasis (i.e., whether or not the tumor was adjacent to the vessel or bronchus) and internal features] and follow-up data (postoperative therapy, complications or adverse effects and survival outcomes). For statistical analysis of the local tumor progression (LTP), disease-free survival and overall survival (OS) rates, Cox regression analysis, along with the Kaplan-Meier method adjusted using inverse probability of treatment weighting (IPTW), were performed. The median follow-up duration in the present study was 31.5 months. Multivariable Cox regression analysis revealed that the CEA level, metastasis diameter and internal features were independent predictors of OS. In the IPTW-adjusted analysis, no significant difference in the 1-year OS rate was observed between the SBRT and MWA groups (92.9 vs. 93.9%; P=0.483); however, a notable discrepancy in the treatment modalities was noted, leading to significant differences in the 2- and 3-year OS rates (65.9 vs. 57.6%, P=0.001, and 44.7 vs. 36.4%, P<0.001, respectively). A significant interaction effect for the treatment modality was observed for LTP (P=0.021). In conclusion, the present study revealed that SBRT and MWA have similar therapeutic effects in terms of prolonging the survival of patients with CRC with lung metastases; however, regarding the local control of lung metastases, MWA is associated with a number of significant advantages.

The Antithetic Roles of IQGAP2 and IQGAP3 in Cancers

The scaffold protein family of IQ motif-containing GTPase-activating proteins (IQGAP1, 2, and 3) share a high degree of homology and comprise six functional domains. IQGAPs bind and regulate the cytoskeleton, interact with MAP kinases and calmodulin, and have GTPase-related activity, as well as a RasGAP domain. Thus, IQGAPs regulate multiple cellular processes and pathways, affecting cell division, growth, cell-cell interactions, migration, and invasion. In the past decade, significant evidence on the function of IQGAPs in signal transduction during carcinogenesis has emerged. Compared with IQGAP1, IQGAP2 and IQGAP3 were less analyzed. In this review, we summarize the different signaling pathways affected by IQGAP2 and IQGAP3, and the antithetic roles of IQGAP2 and IQGAP3 in different types of cancer. IQGAP2 expression is reduced and plays a tumor suppressor role in most solid cancer types, while IQGAP3 is overexpressed and acts as an oncogene. In lymphoma, for example, IQGAPs have partially opposite functions. There is considerable evidence that IQGAPs regulate a multitude of pathways to modulate cancer processes and chemoresistance, but some questions, such as how they trigger this signaling, through which domains, and why they play opposite roles on the same pathways, are still unanswered.

The Predictive Value of CA-125 and Hb for Ocular Metastasis in Hepatocellular Carcinoma Patients

Objective

To explore the risk factors of ocular metastasis (OM) in patients with hepatocellular carcinoma (HCC) by analyzing the demographic characteristics and serum markers.

Methods

From July 2002 to December 2012, 1064 HCC patients were included in our study. The chi-squared test and Student's t-test were used to assess the difference between OM and any other metastasis (NOM). Receiver operating curve (ROC) was used to analyze the diagnostic value of serum biomarkers in HCC patients with OM.

Results

The incidence of OM in HCC patients was 1.88% in our research. There are no significant differences in age, gender, or histopathology in the OM group and the group without any metastasis. Binary logistic regression analysis presented that compared with the patients without cancer metastasis, carbohydrate antigen 125 (CA-125) and hemoglobin (Hb) were risk factors in hepatocellular carcinoma patients with OM (P < 0.05). The ROC curve analysis showed that the areas under the CA-125, Hb, and CA125+Hb curves were 0.877, 0.554, and 0.431, and the cutoff values of CA-125 and Hb each were 115.78 u/mL and 120.50 g/L.

Conclusion

Our data suggest that CA-125 and Hb are risk indicators in hepatocellular carcinoma patients with OM, and that CA-125+Hb has potentially greater utility in diagnosing hepatocellular carcinoma.

The clinical experience of the prognosis in opposite CEA and image change after therapy in stage IV colorectal cancer

Carcinoembryonic antigen (CEA) levels and imaging are used to guide treatment for metastatic colorectal cancer (mCRC). This study evaluated changes in CEA and imaging findings in mCRC patients following systemic therapy and their clinical significance, especially the ones with inconsistent results of CEA and image findings. We enrolled 330 stage IV CRC patients who systemic therapy. Based on the Response Evaluation Criteria in Solid Tumors (RECIST) and a modification for CEA, patients were stratified into consistent and inconsistent response groups. Clinicopathological features and prognoses were compared between each groups. Different CEA/IMG groups showed no significant differences in terms of tumor location, initial CEA level, mucinous component, tumor differentiation and further surgical treatment rate. Inconsistent responses were observed in half of the patients (n = 165, 50%). The prognosis in the inconsistent groups with either CEA-SD or IMG-SD was dependent on the result of the other evaluation method (PR or PD). Cases with conflicting results between CEA and image groups (CEA-RD/IMG-PD, CEA-PD/IMG-PR) had an OS close to that of CEA-SD/IMG-SD (18.2 m, 16.2 m vs. 18.8 m, P = 0.620). The overall survival (OS) in the consistent (PR/PR ro PD/PD) groups were significantly different (P < 0.001). Combining CEA and imaging provides more information about mCRC patients who have undergone systemic therapy. Approximately half the patients have inconsistent responses, which is still valuable in predicting the prognosis.

Potential diagnostic value of the hematological parameters lymphocyte-monocyte ratio and hemoglobin-platelet ratio for detecting colon cancer

Objective

To evaluate the efficacy of using the lymphocyte–monocyte ratio (LMR), hemoglobin–platelet ratio (HPR), and carcinoembryonic antigen (CEA) levels alone or in combination for diagnosing colon cancer.

Methods

We assessed 124 consecutive patients who were pathologically diagnosed with colon cancer and 131 patients who were diagnosed with benign colon tumors in this retrospective study. We then analyzed correlations between LMR, HPR, and clinicopathological findings. The diagnostic values of LMR, HPR, and CEA alone or in combination in colon cancer patients were evaluated by receiver operating characteristic curves.

Results

The median LMR, HPR, and CEA values in colon cancer patients showed significant correlation with the depth of tumor invasion, lymph node metastasis, and TNM stage. Moreover, there was a significant difference in HPR between patients with tumor size ≥5 cm and those with tumor size <5 cm. Compared with LMR, HPR, or CEA alone, combinations of CEA with LMR, CEA with HPR, and HPR with LMR all had higher area under the curve values, among which the combination of all three (LMR, HPR, and CEA) had the highest area under the curve.

Conclusion

The combination of LMR, HPR, and CEA may be a valuable indicator for monitoring colon cancer.

Diagnostic Value of Carcinoembryonic Antigen Combined with Multi-Inflammatory Cell Ratios in Colorectal Cancer

Purpose

To evaluate the diagnostic value of carcinoembryonic antigen (CEA) combined with inflammatory cell ratios in colorectal cancer (CRC).

Methods

This retrospective study compared the data of CRC patients with healthy controls. The CEA levels were measured, and the neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (d-NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) were calculated. The receiver-operating characteristic (ROC) curve was used to assess the diagnostic value of each marker and combined detection. Spearman's rank correlation test was used to analyze the correlation between CEA and NLR, d-NLR, and PLR.

Results

Inflammatory cell ratios and CEA were significantly higher in the CRC group. ROC curve analysis showed that NLR, d-NLR, and PLR had good diagnostic efficacy. The threshold showed that NLR, d-NLR, and PLR were all related to TNM stage, not to age, gender, tumor location, and degree of differentiation. CEA combined with NLR, d-NLR, and PLR (CNDNP) had a significant diagnostic value in CRC. Correlation studies showed that CEA was positively correlated with NLR and d-NLR but not with PLR.

Conclusion

The combination of CEA with CNDNP might be a valuable indicator for CRC diagnosis.

Preoperative Neutrophil-to-Lymphocyte Ratio, Platelet-to-Lymphocyte Ratio, and CEA as the Potential Prognostic Biomarkers for Colorectal Cancer

BACKGROUND

This study was to evaluate the prognostic value of the preoperative neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and carcinoembryonic antigen (CEA) in colorectal cancer (CRC) patients and to identify the potential and easily accessible prognostic biomarkers for CRC.

METHODS

We retrospectively reviewed altogether the records of 330 CRC patients according to inclusion criteria. The clinical characteristics include age at diagnosis, body mass index (BMI), preoperative CEA level, neutrophil , lymphocyte, and platelet count, tumor primary site and size, clinical pathological TNM stage, and survival status were recorded through the review of medical records. The overall survival (OS) was calculated using the Kaplan-Meier method. The Cox proportional hazards model was used for the univariate and multivariate analysis to evaluate the prognostic factors of CRC.

RESULTS

A total of 330 patients were finally included in the current study. The mean follow-up duration was 32.8 ± 19.1 months (range, 0.1-67.7). Compared with the median OS, preoperative high NLR, PLR, and CEA, and low BMI had lower median OS. The NLR and PLR value rise indicates lower median OS in stage I-II CRC; however, the NLR value and CEA level rise indicates lower median OS in stage III-IV CRC. Preoperative high NLR, PLR, and CEA level and low BMI have poorer OS by univariate analysis. By multivariate analysis, the age, sex, N, M stage, and BMI demonstrated independently influence the OS of CRC. NLR was an independent predictor of stage I-II CRC, and the CEA level was an independent predictor of stage III-IV CRC.

CONCLUSIONS

Our results show that preoperative high NLR, PLR, CEA, and low BMI had poorer OS, NLR was an independent predictor of stage I-II CRC, and the CEA level was an independent predictor of stage III-IV CRC.

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.

Colorectal Cancer, Liver Metastases and Biotherapies

(1) Background: colorectal cancer (CRC) is one of the deadliest causes of death by cancer worldwide. Its first main metastatic diffusion spreads to the liver. Different mechanisms such as the epithelial-mesenchymal transition and angiogenesis are the characteristics of this invasion. At this stage, different options are possible and still in debate, especially regarding the use of targeted therapeutics and biotherapies. (2) Methods: A review of the literature has been done focusing on the clinical management of liver metastasis of colorectal cancer and the contribution of biotherapies in this field. (3) Results: In a clinical setting, surgeons and oncologists consider liver metastasis in CRC into two groups to launch adapted therapeutics: resectable and non-resectable. Around these two entities, the combination of targeted therapies and biotherapies are of high interest and are currently tested to know in which molecular and clinical conditions they have to be applied to impact positively both on survival and quality of life of patients.

Addition of bromelain and acetylcysteine to gemcitabine potentiates tumor inhibition in vivo in human colon cancer cell line LS174T

The combinations of Bromelain and Acetylcysteine (BromAc^®) with cytotoxics such as Gemcitabine, 5-Fluorouracil or Oxaliplatin have shown a dramatic reduction in IC50 values in a variety of cancers, including colon cancer, suggesting the possibility of effective treatment without undesired side effects. In the current study, we investigated whether a similar effect is present in vivo using the colorectal cell line LS174T. Animals after acclimatization were randomized and allocated equally in the groups for the different studies (safety, dose-escalation, and efficacy). Drugs were delivered by the intraperitoneal route and animals were monitored for wellbeing. Separately, an efficacy study was conducted with intraperitoneal drug delivery after intraperitoneal tumor induction. At the termination of the experiment, tumors and other tissues were collected for evaluation. BromAc^® was safe when delivered intraperitoneally in a rat model at the concentrations used. Subsequent investigations of these adjuvants in combination with Gemcitabine, Oxaliplatin, and 5-Fluorouracil in mice were also proven to be safe. Preliminary efficacy studies with Oxaliplatin and 5-Fluorouracil on tumor growth (LS174T) were negative. Gemcitabine was assessed with BromAc^® showing an almost 71% tumor inhibition compared to controls. This in vivo study indicates that Gemcitabine at 2 mg/kg in combination with BromAc^® 3 mg/300 mg/Kg was effective and safe, supporting its potential for future clinical application.

Presence of anti-TIF-1γ, anti-Ro52, anti-SSA/Ro60 and anti-Su/Ago2 antibodies in breast cancer: a cross-sectional study

OBJECTIVES

The presence of myositis-specific antibodies (MSA), was recently reported in healthy individuals, cancer patients without myopathy and paraneoplastic rheumatic syndromes. We sought to analyze the frequency of MSA, myositis-associated antibodies (MAA) and autoantibodies related to systemic autoimmune rheumatic diseases (SARD) in breast cancer patients.

METHODS

One hundred fifty-two breast cancer patients were enrolled in a cross-sectional study. Clinical information was collected, and autoantibodies tested by immunoprecipitation of an ³⁵S-methionine-labeled K562 cell extract, enzyme-linked immunosorbent assay (ELISA) and Western blot when indicated. All statistical tests were performed using the software statistical package for the social science (SPSS) ver. 19.0 (IBM Inc., NYSE, USA).

RESULTS

Autoantibodies associated with SARD: anti-52 kD ribonucleoprotein/tripartite motif-containing 21 (anti-Ro52/TRIM21) was found in 5.9% (9/152), anti-Sjögren syndrome-related antigen A/60 kD ribonucleoprotein antibody (anti-SSA/Ro60) in 3.9% (6/152) and anti-Su antigen/Argonaute 2 antibody (anti-Su/Ago2) in 2.6% (4/152). Meanwhile, anti-transcription intermediary factor-1γ (anti-TIF-1γ, p155/140) antibody was positive in 2 cases and anti-polymyositis/scleroderma antibody was detected in one case. As a whole, 14.47% (22/152) of breast cancer patients showed autoantibodies associated with SARD. These specific autoantibodies were not associated with the presence of rheumatic diseases except one rheumatoid arthritis patient positive for anti-Ro52/TRIM21.

CONCLUSIONS

Autoantibodies to TIF-1γ were found in two patients with breast cancer without dermatomyositis (DM). More common specificities were autoantibodies anti-SSA/Ro60, anti-Ro52/TRIM21 and anti-Su/Ago2. More studies are needed in order to establish the biological meaning of the presence of SARD-associated autoantibodies in breast cancer.

HER2 Overexpression and Mismatch Repair Deficiency are Correlated with Malignancy in Colorectal Cancer

PURPOSE

This study was designed to investigate the correlation between the expression of human epidermal growth factor receptor 2 (HER2), mismatch repair (MMR), and clinicopathological parameters and serum tumor markers in a total of 522 resection samples materials from colorectal cancer (CRC) patients. These data were also used to determine the links between HER2 and MMR expression and prognosis.

METHODS

We conducted a retrospective analysis of the clinical data from 522 CRC patients. Immunohistochemistry (IHC) was used to detect HER2 overexpression and MMR deficiency (dMMR) in tumor specimens which were then correlated with various clinicopathological parameters. Prognostic value for HER2 and MMR expression was then evaluated using the data from 105 CRC patients.

RESULTS

HER2 overexpression was identified in 35.63% of the samples evaluated in this study, while the total dMMR rate was 12.64%. Expression of HER2 and several, MMR proteins (MLH1, MSH-2, MSH-6, and PMS-2) were then correlated with tumor location. HER2 overexpression is significantly associated with increased depth of tumor invasion, lymph node metastasis, distant metastases, pTNM staging, vascular invasion, nerve infiltration, and serum carcinoembryonic antigen (CEA) levels. HER2 overexpression and dMMR increased with advancing clinical stage. In addition, deficiencies in MLH1 and PMS2 correlated with HER2 overexpression. Finally, the prognostic evaluations revealed that HER2 overexpression was closely associated with poorer clinical outcomes.

CONCLUSION

HER2 overexpression is significantly correlated with multiple clinicopathological parameters resulting in a poorer prognosis. Moreover, the prognosis of patients with HER2 overexpression was worse, confirming its significance during disease assessment. In clinical practice, clinicians should pay close attention to the HER2 profile of patients as they may require more extensive clinical intervention. In addition, deficiencies in MLH1, MSH-2, MSH-6, or PMS-2 correlate with tumor location, and MLH1 and PMS2 expression is associated with lymph node metastasis and pTNM stage, suggesting that these may be additional markers in CRC risk assessments.

Advances in Imaging Modalities and Contrast Agents for the Early Diagnosis of Colorectal Cancer

Colorectal cancer is one of the most common gastrointestinal cancers worldwide. The mortality rate of colorectal cancer has declined by more than 20% due to the rapid development of early diagnostic techniques and effective treatment. At present, there are many diagnostic modalities available for the evaluation of colorectal cancer, such as the carcinoembryonic antigen test, the fecal occult blood test, endoscopy, X-ray barium meal, computed tomography, magnetic resonance imaging, and radionuclide examination. Sensitive and specific imaging modalities have played an increasingly important role in the diagnosis of colorectal cancer following the rapid development of novel contrast agents. This review discusses the applications and challenges of different imaging techniques and contrast agents applied to detect colorectal cancer, for the purpose of the early diagnosis and treatment of patients with colorectal cancer.

Is It Time to Introduce PET/CT in Rectal Cancer Guidelines?

At the moment, international guidelines for rectal cancer suggest to consider F-FDG PET/CT scan in a few conditions: (1) at disease presentation in case of suspected or proven metastatic synchronous adenocarcinoma with potentially curable M1 disease; (2) in the recurrence workup for serial carcinoembryonic antigen level elevation; (3) in the recurrence workup with metachronous metastases documented by CT, MRI, or biopsy; (4) in case of strong contraindication to IV contrast agent administration; and (5) to evaluate an equivocal finding on a contrast-enhanced CT or MRI. PET/CT is not indicated in the follow-up or surveillance of rectal cancer. On the other hand, an attentive evaluation of the literature shows that PET/CT may also be used in some circumstances with significant levels of diagnostic accuracy. This review article aims to emphasize differences between current international guidelines and scientific literature in the role of PET/CT in rectal cancer.

Noninvasive assessment and therapeutic monitoring of drug-resistant colorectal cancer by MR molecular imaging of extradomain-B fibronectin

Antineoplastic resistance represents a multifaceted challenge for cancer therapy and diagnostics. Extensive molecular heterogeneity, even within neoplasms of the same type, can elicit distinct outcomes of administering therapeutic pressures, frequently leading to the development of drug-resistant populations. Improved success of oncotherapies merits the exploration of precise molecular imaging technologies that can detect not only anatomical but also molecular changes in tumors and their microenvironment, early on in the treatment regimen. To this end, we developed magnetic resonance molecular imaging (MRMI) strategies to target the extracellular matrix oncoprotein, extradomain-B fibronectin (EDB-FN), for non-invasive assessment and therapeutic monitoring of drug-resistant colorectal cancer (CRC). Methods: Two drug-resistant CRC lines generated from parent DLD-1 and RKO cells by long-term treatment with 5'-FU and 5'-FU plus CB-839 respectively, were characterized for functional and gene expression changes using 3D culture, transwell invasion, qRT-PCR, and western blot assays. Contrast-enhanced MRMI of EDB-FN was performed in athymic nu/nu mice bearing subcutaneous tumor xenografts with 40 µmol/kg dose of macrocyclic ZD2-targeted contrast agent MT218 [ZD2-N3-Gd (HP-DO3A)] on a 3T MRS 3000 scanner. Immunohistochemistry was conducted on patient specimens and xenografts using anti-EDB-FN antibody G4. Results: Analyses of TCGA and GTEx databases revealed poor prognosis of colon cancer patients with higher levels of EDB-FN. Similarly, immunohistochemical staining of patient specimens showed increased EDB-FN expression in primary colon adenocarcinoma and hepatic metastases, but none in normal adjacent tissues. Drug-resistant DLD1-DR and RKO-DR cells were also found to demonstrate enhanced invasive potential and significantly elevated EDB-FN expression over their parent counterparts. MRMI of EDB-FN with 40 µmol/kg dose of MT218 (60% lower than the clinical dose) resulted in robust signal enhancement in the drug-resistant CRC xenografts with 84-120% increase in their contrast-to-noise ratios (CNRs) over the non-resistant counterparts. The feasibility of non-invasive therapeutic monitoring using MRMI of EDB-FN was also evaluated in drug-resistant DLD1-DR tumors treated with a pan-AKT inhibitor MK2206-HCl. The treated drug-resistant tumors failed to respond to therapy, which was accurately detected by MRMI with MT218, demonstrating higher signal enhancement and increased CNRs in the 4-week follow-up scans over the pre-treatment scans. Conclusions: EDB-FN is a promising molecular marker for assessing drug resistance. MRMI of EDB-FN with MT218 at a significantly reduced dose can facilitate effective non-invasive assessment and treatment response monitoring of drug-resistant CRC, highlighting its translational potential for active surveillance and management of CRC and other malignancies.

uMUC1-Targeting Magnetic Resonance Imaging of Therapeutic Response in an Orthotropic Mouse Model of Colon Cancer

PURPOSE

Noninvasive assessment of chemotherapeutic response in colon cancer would tremendously aid in therapeutic intervention of cancer patients and improve outcomes. The aim of the study was to evaluate the feasibility of a noninvasive assessment of chemotherapeutic response by magnetic resonance imaging utilizing underglycosylated mucin 1 (uMUC1) tumor antigen as a biomarker of therapeutic response in a colon cancer mouse model.

PROCEDURES

The study was performed by applying molecular imaging approach based on targeting uMUC1 with specific dual-modality imaging probe (MN-EPPT). The probe consisted of dextran-coated iron oxide nanoparticles conjugated to the near infrared fluorescent dye Cy5.5 and to a uMUC1-specific peptide (EPPT) and was used for magnetic resonance imaging (MRI) and fluorescence optical imaging. An orthotopic murine model of colon cancer expressing human uMUC1 peptide (MC38 MUC1) was created along with the control model devoid of the antigen (MC38 neo). Animals received chemotherapy with 5-fluorouracil (5-FU) followed by MN-EPPT-enhanced MR and optical imaging.

RESULTS

In vivo imaging of animals with uMUC1 expressing tumors after 5-FU therapy showed that the average deltaT2 was reduced by 7.27 ms (p = 0.045) compared with animals in control groups indicating lower accumulation of MN-EPPT caused by uMUC1 downregulation. In vivo optical imaging, biodistribution, and fluorescence microscopy confirmed the MRI findings. Interestingly, we found that the group of animals that did not respond to chemotherapy ("progressive disease" per RECIST) showed higher accumulation of MN-EPPT compared to the group of responders ("stable disease") consistent with proliferating tumor cells and increased antigen availability.

CONCLUSIONS

We believe that in application to over 50 % of human cancers expressing uMUC1, our results could provide insight into overall assessment of therapeutic response based on its expression as defined by non-invasive MN-EPPT-enhanced MRI.

Clinical significance and diagnostic value of serum NSE, CEA, CA19-9, CA125 and CA242 levels in colorectal cancer

The present study investigated the value of combinations of five specific tumor biomarkers for the diagnosis of colorectal cancer (CRC): Neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), cancer antigen (CA)19-9, CA125 and CA242. Associations between these markers and clinicopathological characteristics (including the Tumor-Node-Metastasis stage) were also assessed. Serum levels of the 5 markers were compared between 358 patients with CRC and 298 healthy individuals (CRC and control group, respectively). The NSE concentration of the CRC group was significantly higher compared with the control. Furthermore, patients at clinical stage III+IV exhibited significantly higher NSE levels compared with those at stage I+II. The serum NSE level of N⁺ patients was significantly higher compared with the N⁻ group, and the NSE level of M₁ patients was significantly compared with the M₀ group. NSE level was also significantly associated with tumor stage, lymph node metastasis, distant metastasis and hematochezia. The area under the receiver operating characteristic curve (AUC) for NSE in CRC was 0.766, which was significantly higher than that of the other four markers, which ranged from 0.560–0.682. The AUC of NSE, CEA, CA19-9, CA125, CA242 combined was significantly higher compared with any of the markers individually (range, 0.796–0.858). Therefore, serum NSE may be a good clinical tool for the auxiliary diagnosis of colorectal cancer. Besides, the combination of NSE, CEA, CA19-9, CA125 and CA242 was significantly more sensitive compared with NSE alone. Thus, the combined detection of the 5 tumor markers may be more useful for the diagnosis of CRC.

Clinical significance of serum neuron-specific enolase in gastric adenocarcinoma

As a biomarker, neuron-specific enolase (NSE) has been widely recognized in the diagnosis of benign diseases and malignant tumors. This study aimed to investigate the potential diagnostic value of NSE in patients with gastric adenocarcinoma.Serum levels of the NSE were compared between 219 patients with gastric adenocarcinoma and 298 healthy individuals, NSE and clinicopathological parameters were analyzed. Meanwhile, to evaluate the diagnostic capability of NSE, the receiver operating characteristic (ROC), and area under curve (AUC) was calculated.In the present study, the median serum NSE level of the patient group was 20.770 ng/mL, which was higher than that of the control group 15.625 ng/mL (P < .05). Serum NSE level in patients group compared with healthy control was statistically significant (P < .05). Serum NSE level was associated with pathological tumor-node-metastasis (pTNM) staging, lymph node metastasis, and distant metastasis in patients with gastric adenocarcinoma. Besides, the AUC of NSE in gastric adenocarcinoma was 0.742, which was higher than those of the other 3 markers (0.573-0.644). Besides, the AUC of the combined 4 markers was higher than any individual marker (0.778).Serum NSE detecting may have good value for diagnosis of gastric adenocarcinoma. Besides, the combination of NSE, CEA, CA19-9, and CA242 performed even better than any single marker. Thus, the combined detection of the 4 tumor markers may be more useful for the diagnosis of gastric adenocarcinoma.

Correlation study between serum neuro-specific enolase and gastric and colorectal cancers

This study investigated the diagnostic value of preoperative serum neuro-specific enolase (NSE) in gastric cancer (GC) and colorectal cancer (CRC), and the diagnostic viability of combined serum NSE, carcinoembryonic antigen (CEA), cancer antigen (CA)19-9, and CA242.Patients with GC and CRC, and a healthy control group (n = 666 and 266, respectively) were compared with regard to NSE, CEA, CA19-9, and CA242 serum levels. NSE was analyzed for associations with clinicopathological parameters. To estimate the diagnostic potential of NSE, a receiver operating characteristic curve was constructed and the area under the curve (AUCs) was calculated for different patient subgroups.The median serum NSE level of the tumor group (20.925 ng/mL) was significantly higher than that of the control (15.190 ng/mL). Serum NSE was associated with pathological tumor-node-metastasis staging, lymph node metastasis, distant metastasis, vascular invasion, and nerve infiltration. The area under the receiver operating characteristic curve (AUC) for NSE in GC and CRC (0.769) was higher than for the other 3 markers (0.571-0.680). The AUC of the combined markers was higher than for any of the markers individually (0.778-0.810).The AUC for NSE alone suggests it may be an independent tumor marker, and useful for diagnosis of GC and CRC. However, the AUC for combined NSE, CEA, CA19-9, and CA242 was higher and thus potentially more diagnostic value.

CEA as a risk factor in predicting ocular metastasis from colorectal cancer

Objective: Colorectal, closely following pulmonary and breast, is the third predilection site of cancer that lead to death all over the world. Ocular metastasis (OM) of colorectal cancer (CRC) is becoming increasingly common and presents a poor prognosis. In this study, we detected some recognized tumor biomarkers and tried to differentiate the discrepancy between CRC patients with and without OM in order to clarify the risk factor for OM in patients with colorectal cancer. Methods: 1735 patients with colorectal cancer in total from August 2005 to August 2017 were involved in this study. Nonparametric rank sum test and Chi-square test were applied to prescribe whether there were significant differences between OM group and non-ocular metastasis (NOM) group. And binary logistic regression analysis was used to determine the risk factor. Then, we used receiver operating curve (ROC) to assess the diagnostic value of OM in CRC patients. Results: The incidence of OM in CRC patients was 1.12%. No significant differences were found in gender, age, histopathological type, tumor classification and tumor differentiation between OM group and NOM group. Nonparametric rank sum test approved that OM group had higher serum CEA level compared with NOM group. Binary logistic regression indicated that CEA was a risk factor for OM in colorectal cancer patients (p<0.001). ROC curve showed that AUC of CEA was 0.877. The cutoff value of CEA was 12.45 ng/ml, whose sensitivity is 1.000 and its specificity is 0.877. Conclusion: Based on our study, CEA was a risk factor of ocular metastasis in colorectal cancer patients.

Nanoformulated Codelivery of Quercetin and Alantolactone Promotes an Antitumor Response through Synergistic Immunogenic Cell Death for Microsatellite-Stable Colorectal Cancer

Microsatellite-stable colorectal cancer (CRC) is known to be resistant to immunotherapy. The combination of quercetin (Q) and alantolactone (A) was found to induce synergistic immunogenic cell death (ICD) at a molar ratio of 1:4 (Q:A). To achieve ratiometric loading and delivery, the micellar delivery of Q and A (QA-M) was developed with high entrapment efficiency and drug loading at an optimal ratio. QA-M achieved prolonged blood circulation and increased tumor accumulation for both drugs. More importantly, QA-M retained the desired drug ratio (molar ratio of Q to A = 1:4) in tumors at 2 and 4 h after intravenous injection for synergistic immunotherapy. Tumor growth was significantly inhibited in murine orthotopic CRC by the treatment of QA-M compared to PBS and the combination of free drugs (p < 0.005). The combination of nanotherapy stimulated the host immune response to induce long-term tumor destruction and induced memory tumor surveillance with a 1.3-fold increase in survival median time compared to PBS (p < 0.0001) and a combination of free drugs (p < 0.0005). The synergistic therapeutic effect induced by codelivery of Q and A is capable of reactivating antitumor immunity by inducing ICD, causing cell toxicity and modulating the immune-suppressive tumor microenvironment. Such a combination of Q and A with synergistic effects entrapped in a simple and safe nanodelivery system may provide the potential for scale-up manufacturing and clinical applications as immunotherapeutic agents for CRC.

Clinical characteristics of sentinel polyps and their correlation with proximal colon cancer: A retrospective observational study

BACKGROUND

Colorectal cancer is a common malignant tumor of the digestive tract. The relationship between sentinel polyps (rectal polyps with proximal colon cancer) and proximal colon cancer has received extensive attention in recent years. However, there is still no clear conclusion regarding the relationship.

AIM

To investigate the clinical characteristics of sentinel polyps and their correlation with proximal colon cancer.

METHODS

A retrospective analysis of 2587 patients with rectal polyps from January 2006 to December 2017 was performed. According to whether or not proximal colon cancer was diagnosed, the patients were divided into either a sentinel polyp group (192 patients) or a pure rectal polyp group (2395 patients). The endoscopic features, clinicopathological features, therapeutic effects, and short-term prognosis were analyzed and compared between the two groups.

RESULTS

The mean age of patients in the sentinel polyp group was generally higher than that of the pure rectal polyp group, and the positivity rates of anemia, stool occult blood, and tumor markers of the sentinel polyp group were also significantly higher than those in the rectal polyp group (χ² = 90.56, P < 0.01; χ² = 70.30, P < 0.01; χ² = 92.80, P < 0.01). The majority of the patients in the sentinel polyp group had multiple polyps, large polyps, adenomatous polyps, or sessile polyps (χ² = 195.96, P < 0.01; χ² = 460.46, P < 0.01; χ² = 94.69, P < 0.01; χ² = 48.01, P < 0.01). Most of the proximal colon cancers were Duke’s A and B stages in the sentinel polyp group. In the pure rectal polyp group, 2203 patients underwent endoscopic treatment, and all of the patients were cured and discharged. In the sentinel polyp group, 65 patients underwent radical operation, and 61 patients received endoscopic submucosal dissection or endoscopic mucosal resection. Additionally, 21 patients were lost to follow-up after 6-12 mo, and the loss rate was 10.94%. A total of 63.16% of patients experienced remission without tumor recurrence or metastasis, 33.33% of patients experienced tumors regression or improved symptoms, and the other 3.51% of the patients died.

CONCLUSION

If there are multiple, sessile, and adenomatous rectal polyps with a maximum diameter > 1 cm, the possibility of the carcinogenesis of the polyps or of the proximal colon should be monitored closely. These patients should be followed in the short-term and should undergo a whole-colon examination.

Clinical value of detecting IQGAP3, B7-H4 and cyclooxygenase-2 in the diagnosis and prognostic evaluation of colorectal cancer

Background

The IQ-motif-containing GTPase-activating protein (IQGAP) family comprises three members, IQGAP1, IQGAP2 and IQGAP3. IQGAP3 is the latest addition to the family. This study mainly investigated the novel marker IQGAP3 at serum and tumor tissue levels compared with the markers B7-H4 and cyclooxygenase-2 (COX-2) in patients with colorectal cancer (CRC) and in healthy individuals, aiming to evaluate the diagnostic and prognostic value of IQGAP3 for CRC.

Materials and methods

Serum samples were collected prior to any therapy in 118 CRC patients and as part of a routine examination in 85 healthy individuals. Serum IQGAP3, B7-H4 and COX-2 levels were measured using commercially available ELISA kits. Immunohistochemistry was performed to detect the IQGAP3, B7-H4 and COX-2 in tumor tissues and normal para-carcinoma tissues. The receiver operating characteristics (ROC) curve and the area under the curve (AUC) were used to evaluate and compare the diagnostic value of different serum tumor markers. Univariate and multivariate analyses were performed to identify the prognostic risk factors for CRC.

Results

IQGAP3, B7-H4 and COX-2 showed low or high expression in tumor tissues while no expression in normal para-carcinoma tissues. Serum levels of IQGAP3 in CRC group were significantly higher than those in healthy control group (P < 0.001). The IQGAP3 AUC was 0.799, while the B7-H4 AUC was 0.795 and the COX-2 AUC was 0.796. IQGAP3 seemed to be superior to B7-H4 and COX-2 in detecting CRC, with the highest sensitivity among the three markers. Multivariate analysis showed that T stage, N stage, differentiation degree, TNM stage and both serum and tissue IQGAP3, B7-H4 and COX-2 levels were significant prognostic factors for CRC.

Conclusions

IQGAP3 has a better diagnostic efficacy than B7-H4 and COX-2 in detecting CRC and it has value in predicting the prognosis of patients with CRC.

Lower Expression of Gelsolin in Colon Cancer and Its Diagnostic Value in Colon Cancer Patients

Colon cancer is one of the most common malignancies causing the majority of cancer-related deaths. Gelsolin (GSN) has been found to be dysregulated in various cancers. However, the secreted GSN in colon cancer remains largely unknown. In the present study, we explored the expression profile of GSN in colon cancer tissues and the diagnostic value of serum GSN in colon cancer. In addition, the effects of secreted GSN in colon cancer cells were studied. We thus found that immunoreactive GSN levels were significantly lower in colon cancer tissues than those in non-tumor colon tissues. Functional studies demonstrated that secreted GSN could restrain cell invasion and migration in vitro. Mechanistically, dose dependent recombinant GSN down-regulated the expression of MMP2 and MMP9, which might restrain the process of cell invasion and migration. Furthermore, serum levels of GSN were significantly lower in colon cancer patients than those in healthy volunteers, and ROC curves showed serum level of GSN had a better diagnostic value for colon cancer (AUC=0.932) than the traditional tumor biomarker Carcinoembryonic Antigen (CEA) or Carbohydrate Antigen 19-9 (CA199). In conclusion, our results suggest that the secreted GSN restrains the invasion and migration of colon cancer cells. Meanwhile, the serum GSN may be a new biomarker for the diagnosis of colon cancer.

Potential Diagnostic Value Of Combining Inflammatory Cell Ratios With Carcinoembryonic Antigen For Colorectal Cancer

PURPOSE

To evaluate the diagnostic value of combining the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) or lymphocyte-monocyte ratio (LMR) with carcinoembryonic antigen (CEA) in patients with colorectal cancer (CRC).

PATIENTS AND METHODS

The diagnostic performance of inflammatory makers and CEA was evaluated in cohort 1 (664 patients with CRC, 336 patients with colorectal polyps and 664 healthy controls) and validated in cohort 2 (87 patients with CRC and 87 healthy controls) by using receiver operating characteristic curve analysis.

RESULTS

In cohort 1, the NLR, PLR and CEA levels were significantly higher, while the LMR was markedly lower in patients with CRC than in healthy controls. The PLR and LMR were significantly associated with invasion depth and lymph node metastasis. Moreover, significant differences in the PLR and LMR were observed between patients with stage I/II CRC and healthy or polyp controls and those with stage III/IV CRC. Using the NLR, PLR or LMR with CEA resulted in a significantly larger area under the curve (AUC) than any of them used alone. Combining the PLR and LMR with CEA exhibited the best diagnostic value for CRC (AUC=0.892). The AUCs of this combination were 0.864 and 0.783 for distinguishing stage I/II CRC from healthy and polyp controls, respectively. When we used the same cut-off values to assess the diagnostic ability of these markers in cohort 2, similar results were observed, and the PLR, LMR and CEA combination also showed the highest accuracy (AUC=0.936).

CONCLUSION

Combining inflammatory cell ratios with CEA could improve the diagnostic efficacy for CRC patients. The combination of the PLR and LMR with CEA might be a valuable indicator in the early detection and monitoring of CRC patients.

GIDB: a knowledge database for the automated curation and multidimensional analysis of molecular signatures in gastrointestinal cancer

Gastrointestinal (GI) cancer is common, characterized by high mortality, and includes oesophagus, gastric, liver, bile duct, pancreas, rectal and colon cancers. The insufficient specificity and sensitivity of biomarkers is still a key clinical hindrance for GI cancer diagnosis and successful treatment. The emergence of `precision medicine', `basket trial' and `field cancerization' concepts calls for an urgent need and importance for the understanding of how organ system cancers occur at the molecular levels. Knowledge from both the literature and data available in public databases is informative in elucidating the molecular alterations underlying GI cancer. Currently, most available cancer databases have not offered a comprehensive discovery of gene-disease associations, molecular alterations and clinical information by integrated text mining and data mining in GI cancer. We develop GIDB, a panoptic knowledge database that attempts to automate the curation of molecular signatures using natural language processing approaches and multidimensional analyses. GIDB covers information on 8730 genes with both literature and data supporting evidence, 248 miRNAs, 58 lncRNAs, 320 copy number variations, 49 fusion genes and 2381 semantic networks. It presents a comprehensive database, not only in parallelizing supporting evidence and data integration for signatures associated with GI cancer but also in providing the timeline feature of major molecular discoveries. It highlights the most comprehensive overview, research hotspots and the development of historical knowledge of genes in GI cancer. Furthermore, GIDB characterizes genomic abnormalities in multilevel analysis, including simple somatic mutations, gene expression, DNA methylation and prognosis. GIDB offers a user-friendly interface and two customizable online tools (Heatmap and Network) for experimental researchers and clinicians to explore data and help them shorten the learning curve and broaden the scope of knowledge. More importantly, GIDB is an ongoing research project that will continue to be updated and improve the automated method for reducing manual work.

Ethanol Extract of Lycopus lucidus Turcz. ex Benth Inhibits Metastasis by Downregulation of Runx-2 in Mouse Colon Cancer Cells

Lycopus lucidus Turcz. ex Benth (LT) has been broadly used as a traditional medicinal herb in Asia including Korea, China, and Japan due to its noted ability to promote blood circulation and remove blood stasis. However, its anticancer mechanism is not understood. This study aims to elucidate the effects of ethanol extracts of LT (ELT) relative to the role of Runt-related transcription factor- (Runx-) 2 in the invasive and metastatic potentials of mouse colon cancer to determine the underlying mechanisms involved. ELT was evaluated for the antimetastasis activity using CT-26 colon cancer using wound healing, transwell matrigel, and western blot analysis. We used Runx-2-specific siRNA to further determine the relationship between Runx-2 and matrix metalloprotease- (MMP-) 9 in the migration and invasion of CT-26 cells. Runx-2 was first demonstrated to be a transcription factor that plays a remarkable role in diverse biological processes of chondrocytes and osteoblasts, but recently, Runx-2 has been reported to be associated with the progression of certain human cancers. ELT was not altered in its effects on growth inhibition. However, ELT significantly inhibited wound closure and cell invasion in a dose-dependent manner. ELT decreased the metastasis by regulating the activity of MMP-9 and Runx-2 at the translational levels. Our results demonstrate that ELT decreases metastasis by inhibiting the Runx-2–MMP-9 axis. We suggest that it can be used as a novel agent in therapeutic strategies for combating colon cancer.

Noninvasive Biomarkers of Colorectal Cancer: Role in Diagnosis and Personalised Treatment Perspectives

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths worldwide. It has been estimated that more than one-third of patients are diagnosed when CRC has already spread to the lymph nodes. One out of five patients is diagnosed with metastatic CRC. The stage of diagnosis influences treatment outcome and survival. Notwithstanding the recent advances in multidisciplinary management and treatment of CRC, patients are still reluctant to undergo screening tests because of the associated invasiveness and discomfort (e.g., colonoscopy with biopsies). Moreover, the serological markers currently used for diagnosis are not reliable and, even if they were useful to detect disease recurrence after treatment, they are not always detected in patients with CRC (e.g., CEA). Recently, translational research in CRC has produced a wide spectrum of potential biomarkers that could be useful for diagnosis, treatment, and follow-up of these patients. The aim of this review is to provide an overview of the newer noninvasive or minimally invasive biomarkers of CRC. Here, we discuss imaging and biomolecular diagnostics ranging from their potential usefulness to obtain early and less-invasive diagnosis to their potential implementation in the development of a bespoke treatment of CRC.

Monitoring neoadjuvant therapy responses in rectal cancer using multimodal nonlinear optical microscopy

Most patients with rectal cancer have a better prognosis after receiving neoadjuvant therapy because of its remarkable curative effect. However, no device delivers real-time histopathologic information on treatment response to help clinicians tailor individual therapeutic strategies. We assessed the potential of multimodal nonlinear optical microscopy to monitor therapeutic responses, including tumoral and stromal responses. We found that two-photon excited fluorescence imaging can, without labeling, identify colloid response, inflammatory cell infiltration, vascular proliferation, and tumor regression. It can also directly detect rare residual tumor cells, which may be helpful for distinguishing tumor shrinkage from tumor fragmentation. In addition, second harmonic generation imaging shows the ability to monitor three types of fibrotic responses: mature, intermediate, and immature. We also determined nonlinear spectra, collagen density, and collagen orientation indexes to quantitatively analyze the histopathologic changes induced by neoadjuvant therapy in rectal cancer. Our work demonstrates that nonlinear optical microscopy has the potential to become a label-free, real-time, in vivo medical imaging technique and provides the groundwork for further exploration into the application of nonlinear optical microscopy in a clinical setting.

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.

Inoculated Cell Density as a Determinant Factor of the Growth Dynamics and Metastatic Efficiency of a Breast Cancer Murine Model

4T1 metastatic breast cancer model have been widely used to study stage IV human breast cancer. However, the frequent inoculation of a large number of cells, gives rise to fast growing tumors, as well as to a surprisingly low metastatic take rate. The present work aimed at establishing the conditions enabling high metastatic take rate of the triple-negative murine 4T1 syngeneic breast cancer model. An 87% 4T1 tumor incidence was observed when as few as 500 cancer cells were implanted. 4T1 cancer cells colonized primarily the lungs with 100% efficiency, and distant lesions were also commonly identified in the mesentery and pancreas. The drastic reduction of the number of inoculated cells resulted in increased tumor doubling times and decreased specific growth rates, following a Gompertzian tumor expansion. The established conditions for the 4T1 mouse model were further validated in a therapeutic study with peguilated liposomal doxorubicin, in clinical used in the setting of metastatic breast cancer. Inoculated cell density was proven to be a key methodological aspect towards the reproducible development of macrometastases in the 4T1 mouse model and a more reliable pre-clinical assessment of antimetastatic therapies.

The use of personalized biomarkers and liquid biopsies to monitor treatment response and disease recurrence in locally advanced rectal cancer after neoadjuvant chemoradiation

Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is the mainstay treatment for locally advanced rectal cancer. Variable degrees of tumor regression are observed after nCRT and alternative treatment strategies, including close surveillance without immediate surgery, have been investigated to spare patients with complete tumor regression from potentially adverse outcomes of radical surgery. However, clinical and radiological assessment of response does not allow accurate identification of patients with complete response. In addition, surveillance for recurrence is similarly important for these patients, as early detection of recurrence allows salvage resections and adjuvant interventions. We report the use of liquid biopsies and personalized biomarkers for monitoring treatment response to nCRT and detecting residual disease and recurrence in patients with rectal cancer. We sequenced the whole-genome of four rectal tumors to identify patient-specific chromosomal rearrangements that were used to monitor circulating tumor DNA (ctDNA) in liquid biopsies collected at diagnosis and during nCRT and follow-up. We compared ctDNA levels to clinical, radiological and pathological response to nCRT. Our results indicate that personalized biomarkers and liquid biopsies may not be sensitive for the detection of microscopic residual disease. However, it can be efficiently used to monitor treatment response to nCRT and detect disease recurrence, preceding increases in CEA levels and radiological diagnosis. Similar good results were observed when assessing tumor response to systemic therapy and disease progression. Our study supports the use of personalized biomarkers and liquid biopsies to tailor the management of rectal cancer patients, however, replication in a larger cohort is necessary to introduce this strategy into clinical practice.

Imaging in Colorectal Cancer: Progress and Challenges for the Clinicians

The use of imaging in colorectal cancer (CRC) has significantly evolved over the last twenty years, establishing important roles in surveillance, diagnosis, staging, treatment selection and follow up. The range of modalities has broadened with the development of novel tracer and contrast agents, and the fusion of technologies such as positron emission tomography (PET) and computed tomography (CT). Traditionally, the most widely used modality for assessing treatment response in metastasised colon and rectal tumours is CT, combined with use of the RECIST guidelines. However, a growing body of evidence suggests that tumour size does not always adequately correlate with clinical outcomes. Magnetic resonance imaging (MRI) is a more versatile technique and dynamic contrast-enhanced (DCE)-MRI and diffusion-weighted (DW)-MRI may be used to evaluate biological and functional effects of treatment. Integrated fluorodeoxyglucose (FDG)-PET/CT combines metabolic and anatomical imaging to improve sensitivity and specificity of tumour detection, and a number of studies have demonstrated improved diagnostic accuracy of this modality in a variety of tumour types, including CRC. These developments have enabled the progression of treatment strategies in rectal cancer and improved the detection of hepatic metastatic disease, yet are not without their limitations. These include technical, economical and logistical challenges, along with a lack of robust evidence for standardisation and formal guidance. In order to successfully apply these novel imaging techniques and utilise their benefit to provide truly personalised cancer care, advances need to be clinically realised in a routine and robust manner.

Tumour-associated antigens and their anti-cancer applications

So far, a number of tumour-associated antigens (TAAs), such as heat shock proteins, alpha-fetoprotein, carcino-embryonic antigen and others have been identified in a variety of malignant tumours. Differences in the expression levels of TAAs in cancers compared with normal cells have led to these antigens being investigated as diagnostic and prognostic biomarkers or exciting targets in cancer treatment. Here, we systematically list the current representative TAAs to shed some light on current approaches and challenges for their anti-cancer application in cancer therapy. In this review, we discuss the ongoing pre-clinical studies and clinical development of TAAs in human cancers, and the potential application of these TAAs in the diagnosis and prognosis for cancer treatment.

Clinical Application of Serum Tumor Abnormal Protein (TAP) in Colorectal Cancer Patients

OBJECTIVE

To explore the association of serum tumor abnormal protein (TAP) with other serological biomarkers e.g. carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125), carbohydrate antigen 19-9 (CA19-9) and its clinical application in colorectal cancer (CRC) patients.

METHODS

Patients (N=98) were enrolled into this study with histologically or cytologically confirmed CRC. Using a test kit, the level of TAP was determined, while chemiluminescence was used to measure the levels of some other common serological biomarkers e.g. CEA, CA125 and CA19-9.

RESULTS

The area of TAP condensed particulate matter decreased after chemotherapy compared with before chemotherapy when CT or MRI scans showed disease control. In contrast, it increased with disease progression (P<0.05). Furthermore, a statistically significant difference was confirmed in monitoring of TAP and common serological biomarkers e.g. CEA and CA19-9 (p<0.05).

CONCLUSIONS

Detecting TAP in CRC patients has high sensitivity and specificity and can be used as a new independent indicator for clinically monitoring CRC patients in the course of chemotherapy.

Layer-resolved colorectal tissues using nonlinear microscopy

In this work, multiphoton microscopy (MPM), based on the nonlinear optical processes two-photon excited fluorescence (TPEF) and second harmonic generation (SHG), was extended to evaluate the feasibility of using MPM to distinguish layers of the bowel wall. It was found that MPM has the ability to identify the four-layer microstructures of colorectal tissues including mucosa, submucosa, muscularis propria, and serosa as there are many intrinsic signal sources in each layer. Our results also showed the capability of using the quantitative analyses of MPM images for quantifying some feature parameters including the nuclear area, nuclear-to-cytoplasmic ratio, and optical redox ratio. This work demonstrates that MPM has the potential in noninvasively monitoring the development and progression of colorectal diseases and then guiding effective treatment.

Assessment of colloid response by nonlinear optical microscopy after preoperative radiochemotherapy for rectal carcinoma

Colloid response is a type of tumor response that occurs after preoperative radiochemotherapy for rectal carcinoma. Given its important influence on survival, the colloid response should be considered when estimating histopathological reactions. Here, multiphoton microscopy (MPM) was applied to evaluate the colloid response ex vivo. This study demonstrated that MPM has the capability to visualize the colloid response in the absence of labels and can, in particular, identify rare residual carcinomatous cells in mucin pools. These results highlight the potential of this nonlinear optical technique as a diagnostic tool for tumor response after neoadjuvant treatment.

Evolution of imaging in rectal cancer: multimodality imaging with MDCT, MRI, and PET

Magnetic resonance imaging (MRI), multidetector computed tomography (MDCT), and positron emission tomography (PET) are complementary imaging modalities in the preoperative staging of patients with rectal cancer, and each offers their own individual strengths and weaknesses. MRI is the best available radiologic modality for the local staging of rectal cancers, and can play an important role in accurately distinguishing which patients should receive preoperative chemoradiation prior to total mesorectal excision. Alternatively, both MDCT and PET are considered primary modalities when performing preoperative distant staging, but are limited in their ability to locally stage rectal malignancies. This review details the role of each of these three modalities in rectal cancer staging, and how the three imaging modalities can be used in conjunction.

Loss of miR-200 family in 5-fluorouracil resistant colon cancer drives lymphendothelial invasiveness in vitro

Invasive colorectal cancer is associated with poor prognosis requiring treatment with systemic chemotherapies usually including 5-fluorouracil. A consequence of prolonged treatment is the acquisition of resistance eventually resulting in the recurrence of highly metastatic cancer cells. To address the relationship between drug resistance and increased lymphatic metastatic potential, we used a 3D co-culture model of colon tumour cell spheroids of parent CCL227 cells and subclones with gradually increasing resistance against 5-fluorouracil. From each investigated cell line, homogeneous tumour spheroids were generated in the presence of methylcellulose yielding emboli of ∼700 µm diameter. When invasive, tumour spheroids disrupt the continuous lymphendothelial cell (LEC) layer and generate a 'circular chemorepellent-induced defect' (CCID), reminiscent of the entry gates through which tumour emboli intravasate lymphatic vasculature. Here we provide evidence that increasingly chemoresistant colon cancer spheroids were strongly associated with enhanced intravasative properties. In naïve CCL227 spheroids, miR-200 family members were released into exosomes thereby repressing the epithelial to mesenchymal transition-regulating transcription factors ZEB1 and SLUG in LEC. As a consequence of attenuated plasticity and migration of LEC, CCID formation was impaired. Loss of exosomal transferred miR-200c in resistant colon cells rendered LEC more susceptible to pro-migratory signals that were generated and directly transmitted by colon cancer spheroids. This observation indicates a common molecular axis in colon cancer and LEC where miR-200 family members act as regulators of ZEB proteins. The data support the notion that horizontal miR-200 signalling prevents the permeation of cells into adjacent epithelia and contributes to organ integrity.

The role of IGFBP-5 in mediating the anti-proliferation effect of tetrandrine in human colon cancer cells

Colon cancer is one of the most common malignancies, causes considerable morbidity and mortality. The current treatment for colon cancer is more modest than had been hoped. There is an urgent clinical need to explore new agents or adjuvants for colon cancer treatment. Natural products and their derivates act as one of the major source for anticancer agent. In the present study, we investigated the anti-proliferation and chemoprevention effects of tetrandrine (Tet) on colon cancer cells to uncover the possible molecular basis of this effect. We found that Tet can inhibit proliferation and induce apoptosis in LoVo cells. With dimethylhydrazine (DMH) and dextran sodium sulfate (DSS) induced colon cancer model, we found that Tet can prevent or inhibit DMH plus DSS induced aberrant crypt foci (ACF) and colon cancer formation, as well as suppress tumor growth in the xenograft colon cancer model. Tet can downregulate the expression of IGFBP-5 in LoVo cells. Exogenous expression of IGFBP-5 can attenuate the anti-cancer activity of Tet, while IGFBP-5 knockdown potentiates this effect of Tet on LoVo cells. Tet can inhibit Wnt/β-catenin signaling transduction, which can be partly reversed by exogenous expression of IGFBP-5, but is enhanced by IGFBP-5 knockdown. Our results demonstrated that the anticancer activity of Tet in colon cancer cells may be mediated partly by downregulating the expression of IGFBP-5, thus inactivating Wnt/β-catenin signaling transduction.

Computerized PET/CT image analysis in the evaluation of tumour response to therapy

Current cancer therapy strategy is mostly population based, however, there are large differences in tumour response among patients. It is therefore important for treating physicians to know individual tumour response. In recent years, many studies proposed the use of computerized positron emission tomography/CT image analysis in the evaluation of tumour response. Results showed that computerized analysis overcame some major limitations of current qualitative and semiquantitative analysis and led to improved accuracy. In this review, we summarize these studies in four steps of the analysis: image registration, tumour segmentation, image feature extraction and response evaluation. Future works are proposed and challenges described.

Clinicopathological significance and potential drug target of O6-methylguanine-DNA methyltransferase in colorectal cancer: a meta-analysis

Emerging evidence indicates that O(6)-methylguanine-DNA methyltransferase (MGMT) is a candidate for tumor suppression in several types of human tumors including colorectal cancer (CRC). However, the correlation between MGMT hypermethylation and clinicopathological characteristics of CRC remains unclear. In this study, we conducted a systematic review and meta-analysis to quantitatively evaluate the effects of MGMT hypermethylation on the incidence of CRC and clinicopathological characteristics. A comprehensive literature search was done from Web of Science, the Cochrane Library Database, PubMed, EMBASE, CINAHL, and the Chinese Biomedical Database for related research publications written in English and Chinese. Methodological quality of the studies was also evaluated. Analyses of pooled data were performed with Review Manager 5.2. Odds ratio (OR) and hazard ratio (HR) were calculated and summarized, respectively. Final analysis from 28 eligible studies was performed. MGMT hypermethylation is found to be significantly higher in CRC than in normal colorectal mucosa, the pooled OR from 13 studies including 1085 CRC and 899 normal colorectal mucosa, OR = 6.04, 95 % confidence interval (CI) = 4.69-7.77, p < 0.00001. MGMT hypermethylation is also significantly higher in colorectal adenoma than in normal colorectal mucosa, but it is significantly less compared to that in CRC patients. Interestingly, MGMT hypermethylation is correlated with sex status and is significantly higher in female than in male. MGMT hypermethylation is also associated with high levels of microsatellite instability (MSI). The pooled HR for overall survival (OS) shows that MGMT hypermethylation is not associated with worse survival in CRC patients. The results of this meta-analysis suggest that MGMT hypermethylation is associated with an increased risk and high levels of MSI and may play an important role in CRC initiation. However, MGMT hypermethylation may play an important role in the early stage of CRC progression and development, as well as having limited value in prediction of prognosis in CRC patients. We also discussed that MGMT may serve as a potential drug target of CRC.