Role of miRNA-210, miRNA-21 and miRNA-126 as diagnostic biomarkers in colorectal carcinoma: impact of HIF-1α-VEGF signaling pathway

Colorectal cancer (CRC) is a major cause of death worldwide. Novel non-invasive, high diagnostic value screening test is urgently needed to improve survival rate, treatment and prognosis. Stable, small, circulating microRNA (miRNA) offers unique opportunities for the early diagnosis of several diseases. It acts as tumor oncogenes or suppressors and involve in cell death, survival, and metastasis. Communication between miRNA and carcinogenesis is critical but it still not clear and needs further investigation. The aim of our study is to evaluate the role of miR-210, miR-21, miR-126, as non-invasive diagnostic biomarkers for screening, early detection of CRC, studying their correlation with prognostic variables, and clarifying the roles of miRNAs on HIF-1α-VEGF signaling pathway. The expression of miR-210, miR-21 and miR-126 was performed using qRT-PCR in adenocarcinoma (no?=?35), adenomas (no?=?51), and neoplasm free controls (no?=?101). Serum levels of VEGF and HIF-1α was determined by ELISA Kit. The results show that the expression of miR-210, miR-21, VEGF, HIF-1α was significantly up-regulated while that miRNA-126 was down-regulated in both adenocarcinoma and adenomas compared with controls (p?<?0.001 for each). No significant difference was noted comparing patients with adenocarcinoma and adenomas. The three miRNAs correlated with VEGF, HIF-α. The miR-210 and miR-21 associated with TNM classification and clinical staging of adenocarcinoma (p?<?0.001) and they show high diagnostic value with sensitivity and specificity 88.6%, 90.1% and 91.4%, 95.0% respectively. Our study revealed that circulating miR-210, miR-21 were up-regulated while miR-126 was down-regulated in CRC and adenomas patients, they all correlated with TNM staging and they had high diagnostic value. HIF-1α VEGF signaling pathways regulated by miRNAs played a role in colon cancer initiation. To the best of our knowledge, this is the first study of this miRNAs panel in CRC in our community. These data suggested that these biomarkers could be a potential novel, non-invasive marker for early diagnosis, screening and predicting prognosis of CRC. Understanding the molecular functions by which miRNAs affect cancer and understanding its roles in modulating the signaling output of VEGF might be fruitful in reducing the incidence and slowing the progression of this dark malignancy.

     

Human Intestinal Circadian Clock: Expression of Clock Genes in Colonocytes Lining the Crypt

Biological clock components have been detected in many epithelial tissues of the digestive tract of mammals (oral mucosa, pancreas, and liver), suggesting the existence of peripheral circadian clocks that may be entrainable by food. Our aim was to investigate the expression of main peripheral clock genes in colonocytes of healthy humans and in human colon carcinoma cell lines. The presence of clock components was investigated in single intact colonic crypts isolated by chelation from the biopsies of 25 patients (free of any sign of colonic lesions) undergoing routine colonoscopy and in cell lines of human colon carcinoma (Caco2 and HT29 clone 19A). Per‐1, per‐2, and clock mRNA were detected by real‐time RT‐PCR. The three‐dimensional distributions of PER‐1, PER‐2, CLOCK, and BMAL1 proteins were recorded along colonic crypts by immunofluorescent confocal imaging. We demonstrate the presence of per‐1, per‐2, and clock mRNA in samples prepared from colonic crypts of 5 patients and in all cell lines. We also demonstrate the presence of two circadian clock proteins, PER‐1 and CLOCK, in human colonocytes on crypts isolated from 20 patients (15 patients for PER‐1 and 6 for CLOCK) and in colon carcinoma cells. Establishing the presence of clock proteins in human colonic crypts is the first step toward the study of the regulation of the intestinal circadian clock by nutrients and feeding rhythms.     

结直肠癌无创筛查技术研究进展

结直肠癌和高危腺瘤的早期诊断及治疗,能够大大降低其死亡率。因而,在临床普及结直肠癌筛查有助于遏制该疾病的危害。目前,结肠镜检查是结直肠癌诊断的金标准,但该方法需要肠道准备,且具有侵入性,易造成肠道穿孔等缺点,导致患者依从性差,不利于其作为大规模筛查技术推广实施。近年来非侵入性的结直肠癌诊断方法发展迅速,这类方法主要通过检测粪便或血液样本中与结直肠癌发生相关的生物标志物,为结直肠癌的无创筛查提供了可能。但由于粪便、血液样本的成分复杂,对其中生物标志物的检测技术仍然在不断研究和完善中。本文分别从基于粪便样本和血液样本的检测技术两方面入手,探讨了近年来结直肠癌无创筛查技术的研究进展。     

Dysregulation of MicroRNAs in Colonic Field Carcinogenesis: Implications for Screening

Colorectal cancer (CRC) screening tests often have a trade-off between efficacy and patient acceptability/cost. Fecal tests (occult blood, methylation) engender excellent patient compliance but lack requisite performance underscoring the need for better population screening tests. We assessed the utility of microRNAs (miRNAs) as markers of field carcinogenesis and their potential role for CRC screening using the azoxymethane (AOM)-treated rat model. We found that 63 miRNAs were upregulated and miR-122, miR-296-5p and miR-503# were downregulated in the uninvolved colonic mucosa of AOM rats. We monitored the expression of selected miRNAs in colonic biopsies of AOM rats at 16 weeks and correlated it with tumor development. We noted that the tumor bearing rats had significantly greater miRNA modulation compared to those without tumors. The miRNAs showed good diagnostic performance with an area under the receiver operator curve (AUROC) of >0.7. We also noted that the miRNA induction in the colonic mucosa was mirrorred in the mucus layer fecal colonocytes isolated from AOM rat stool and the degree of miRNA induction was greater in the tumor bearing rats compared to those without tumors. Lastly, we also noted significant miRNA modulation in the Pirc rats- the genetic model of colon carcinogenesis, both in the uninvolved colonic mucosa and the fecal colonocytes. We thus demonstrate that miRNAs are excellent markers of field carcinogenesis and could accurately predict future neoplasia. Based on our results, we propose an accurate, inexpensive, non-invasive miRNA test for CRC risk stratification based on rectal brushings or from abraded fecal colonocytes.     

TCF21 and PCDH17 methylation: An innovative panel of biomarkers for a simultaneous detection of urological cancers

The three main types of urological cancers are mostly curable by surgical resection, if early detected. We aimed to identify novel DNA methylation biomarkers common to these three urological cancers, potentially suitable for non-invasive testing. From a candidate list of markers created after gene expression assessment of pharmacologically treated cell lines and tissue samples, two genes were selected for further validation. Methylation levels of these genes were quantified in a total of 12 cancer cell lines and 318 clinical samples. PCDH17 and TCF21 methylation levels provided a sensitivity rate of 92% for bladder cancer, 67% for renal cell tumors and 96% for prostate cancer. Methylation levels were significantly different from those of cancer free individuals (n = 37) for all tumor types (p < 0.001), providing 83% sensitivity and 100% specificity for cancer detection. Although in urine samples the sensitivity was 60%, 32% and 26% for bladder, renal, and prostate tumors, respectively (39% overall), absolute specificity was retained. We identified novel and highly specific methylation markers common to the three main urological cancers. However, additional efforts are required to increase the assay’s sensitivity, enabling the simultaneous non-invasive screening of urological tumors in a single voided urine analysis.     

乳腺癌早期筛查和诊断生物标志物研究进展

2020年全球乳腺癌(breast cancer,BC)新发病例达226万例,占全部肿瘤新发病例的11.7%,是全世界发病率最高的癌症。早期发现、早期诊断和早期治疗是降低乳腺癌死亡率及改善预后的关键。尽管乳房X光筛查被广泛用作乳腺癌筛查的工具,但其假阳性、辐射性和过度诊断仍是亟待解决的问题。因此,亟需开发易于获取且稳定可靠的生物标志物,用于乳腺癌无创筛查和诊断。近年来多项研究显示来自乳腺癌患者血液中的循环肿瘤细胞DNA(circulating tumor cell DNA,ctDNA)、癌胚抗原(carcinoembryonic antigen,CEA)、糖类抗原15-3(carbohydrate antigen 15-3,CA15-3)、细胞外囊泡(extracellular vesicles,EV)、循环miRNA和BRCA基因突变等生物标志物,以及来自人体尿液、呼出气体(volatile organic compounds,VOCs)和乳头吸出液(nipple aspirate fluid,NAF)中的磷脂、miRNA、苯乙酮和十六烷等多种生物标志物与乳腺癌早期筛查和诊断密切相关。本文综述了上述生物标志物在乳腺癌早期筛查和诊断中的应用。     

Biological Mechanisms Underlying Structural Changes Induced by Colorectal Field Carcinogenesis Measured with Low-Coherence Enhanced Backscattering (LEBS) Spectroscopy

We previously reported the utility of Low-Coherence Enhanced Backscattering (LEBS) Spectroscopy in detecting optical changes in uninvolved rectal mucosa, changes that are indicative of the presence of advanced colorectal adenomas elsewhere in the colon (field carcinogenesis). We hypothesized that the alterations in optical signatures are due to structural changes in colonocytes. To elucidate those colonocyte changes, we used LEBS and an early time point in an animal model of colorectal field carcinogenesis – rats treated with azoxymethane (AOM). Changes in LEBS markers in intact mucosa from AOM-treated rats could be at least partially attributed to changes in colonocytes. To investigate the molecular mechanisms underlying the colonocyte abnormalities in premalignant colon, we took a candidate approach. We compared expression profiles of genes implicated directly or indirectly in cytoskeletal dysregulation in colorectal tissues from saline-treated versus AOM-treated rats. Our data suggest that a number of genes known to affect colon tumorigenesis are up-regulated in colonocytes, and genes previously reported to be tumor suppressors in metastatic cancer are down-regulated in colonocytes, despite the colonocytes being histologically normal. To further understand the role of the cytoskeleton in generating changes in optical markers of cells, we used pharmacological disruption (using colchicine) of the cytoskeleton. We found that differences in optical markers (between AOM- and control-treated rats) were negated by the disruption, suggesting cytoskeletal involvement in the optical changes. These studies provide significant insights into the micro-architectural alterations in early colon carcinogenesis, and may enable optimization of both bio-photonic and molecular risk stratification techniques to personalize colorectal cancer screening.     

Discovery and Validation of New Potential Biomarkers for Early Detection of Colon Cancer

Background

Accurate detection of characteristic proteins secreted by colon cancer tumor cells in biological fluids could serve as a biomarker for the disease. The aim of the present study was to identify and validate new serum biomarkers and demonstrate their potential usefulness for early diagnosis of colon cancer.

Methods

The study was organized in three sequential phases: 1) biomarker discovery, 2) technical and biological validation, and 3) proof of concept to test the potential clinical use of selected biomarkers. A prioritized subset of the differentially-expressed genes between tissue types (50 colon mucosa from cancer-free individuals and 100 normal-tumor pairs from colon cancer patients) was validated and further tested in a series of serum samples from 80 colon cancer cases, 23 patients with adenoma and 77 cancer-free controls.

Results

In the discovery phase, 505 unique candidate biomarkers were identified, with highly significant results and high capacity to discriminate between the different tissue types. After a subsequent prioritization, all tested genes (N = 23) were successfully validated in tissue, and one of them, COL10A1, showed relevant differences in serum protein levels between controls, patients with adenoma (p = 0.0083) and colon cancer cases (p = 3.2e-6).

Conclusion

We present a sequential process for the identification and further validation of biomarkers for early detection of colon cancer that identifies COL10A1 protein levels in serum as a potential diagnostic candidate to detect both adenoma lesions and tumor.

Impact

The use of a cheap serum test for colon cancer screening should improve its participation rates and contribute to decrease the burden of this disease.     

Human intestinal circadian clock: expression of clock genes in colonocytes lining the crypt

Biological clock components have been detected in many epithelial tissues of the digestive tract of mammals (oral mucosa, pancreas, and liver), suggesting the existence of peripheral circadian clocks that may be entrainable by food. Our aim was to investigate the expression of main peripheral clock genes in colonocytes of healthy humans and in human colon carcinoma cell lines. The presence of clock components was investigated in single intact colonic crypts isolated by chelation from the biopsies of 25 patients (free of any sign of colonic lesions) undergoing routine colonoscopy and in cell lines of human colon carcinoma (Caco2 and HT29 clone 19A). Per-1, per-2, and clock mRNA were detected by real-time RT-PCR. The three-dimensional distributions of PER-1, PER-2, CLOCK, and BMAL1 proteins were recorded along colonic crypts by immunofluorescent confocal imaging. We demonstrate the presence of per-1, per-2, and clock mRNA in samples prepared from colonic crypts of 5 patients and in all cell lines. We also demonstrate the presence of two circadian clock proteins, PER-1 and CLOCK, in human colonocytes on crypts isolated from 20 patients (15 patients for PER-1 and 6 for CLOCK) and in colon carcinoma cells. Establishing the presence of clock proteins in human colonic crypts is the first step toward the study of the regulation of the intestinal circadian clock by nutrients and feeding rhythms.     

Use of the micronucleus assay with exfoliated epithelial cells as a biomarker for monitoring individuals at elevated risk of genetic damage and in chemoprevention trials.

This review summarises the current database on the micronucleus (MN) assay with exfoliated cells (MEC assay) and evaluates the predictive value of this model for the detection of human cancer risks. The MEC test is a cost effective, non-invasive method, in which the formation of MN in exfoliated cells from different organs, such as oral and nasal cavity, bladder, cervix, and oesophagus is used as an endpoint to detect endogenous, lifestyle, occupational and environmental exposures to genotoxins as well as chemoprotection of various compounds in intervention studies. The results suggest that the MN assay might be a useful approach to identify antimutagens which are protective in humans. Based on the comparison of the data from MN experiments with results from epidemiological cancer studies, we conclude that the MEC assay is a useful biomarker for the detection of human cancer risk in organs to which the MEC test can be applied. However, the current data base is not sufficient to draw a firm conclusion on the specificity of this approach.     

The role of serum pepsinogen and gastrin test for the detection of gastric cancer in Korea

Background and Aim: This study was performed to determine whether serum pepsinogen (PG) and gastrin testing can be used to detect gastric cancer in Korea. Methods: Serum levels of PG I (sPGI) and sPGII, PG I/II ratios, and gastrin levels were measured in 1006 patients with gastroduodenal diseases including cancer. Follow‐up tests were performed 1 year after Helicobacter pylori eradication. Results: sPGI and sPGII levels increased and PG I/II ratios decreased in line with the severity of activity, chronic inflammation, and the presence of H. pylori (p < .01). In contrast, sPGI levels and PG I/II ratios decreased in proportion with the severity of atrophic gastritis (AG)/intestinal metaplasia (p < .01). Gastrin levels were found to be correlated with chronic inflammation negatively in the antrum but positively in the corpus. H. pylori eradication reduced sPGI, sPGII, and gastrin levels, and increased PG I/II ratios to the levels of H. pylori‐negative patients, and was found to be correlated with reductions in activity and chronic inflammation of gastritis. The sensitivity and specificity of a PG I/II ratio of ≤ 3.0 for the detection of dysplasia or cancer were 55.8–62.3% and 61%, respectively. In addition, sPGI and sPGII levels of intestinal‐type cancer were significantly lower than those of the diffuse type, respectively (p = .008 and p = .05, respectively). Gastric cancer risk was highest in the H. pylori‐positive, low PGI/II ratio (≤ 3.0) group with an odds ratio of 5.52 (confidence interval: 2.83–10.77). Conclusion: PG I/II ratio (≤ 3.0) was found to be a reliable marker for the detection of dysplasia or gastric cancer, especially of the intestinal type. This detection power of PG I/II ratio (≤ 3.0) significantly increased in the presence of H. pylori, and thus, provides a means of selecting those at high risk of developing gastric cancer in Korea.     

Plasma levels of resistin-like molecule beta in humans

Background: Resistin-like molecules (RELM) are expressed in many tissues and among those, RELMβ is most abundantly expressed in the colon. Based on animal studies, RELMβ is induced by high fat diets, obesity, and intestinal microflora and may play a role in insulin resistance and intestinal inflammation. In the present study, we evaluated whether RELMβ could be measured in human plasma and the influence of selected host and behavioral factors on RELMβ levels, including known risk factors for colorectal cancer. Methods: The subjects for this pilot study were derived from healthy controls who participated in a population-based case–control study of colorectal cancer in Metropolitan Detroit. The subjects were 45–80 years of age without history of cancer or colorectal resection. Results: RELMβ was present in human plasma, with levels in the range of 0.08–0.26 ng/mL. Lower RELMβ levels were found in subjects with non-Caucasian race, lower pack-years of smoking, and higher physical activity index scores. Other variables such as dietary intakes, gender, obesity, use of non-steroidal anti-inflammatory agents and history of polyps were not associated with RELMβ levels. Conclusions: The direct association of RELMβ with smoking and inverse association with physical activity, both of which are risk factors for colon cancer, indicates that RELMβ may be involved in mediating the effects of these two lifestyle factors on risk of colon cancer.     

子宫颈癌细胞学新型生物标志、诊断标志物的筛选和开发现状

子宫颈癌至今仍是全球范围内一个重要的公共卫生问题，是妇女疾病死亡的主要原因之一。因此，子宫颈癌细胞学的筛查、早期诊断和治疗越来越受到重视，虽然新的技术不断推出使子宫颈癌的早期筛查及诊治水平有了很大提高，但仍缺乏新型的特异性生物学标志物。本文从新的子宫颈癌相关蛋白生物标志物和诊断靶标的发现，治疗子宫颈癌的药物作用、治疗靶标和作用机制的评估，子宫颈癌相关微小核糖核酸作为诊断和治疗靶标的筛选等方面对子宫颈脱落细胞筛查方法的开发和研究进展进行综述，为子宫颈癌的早期筛查和诊断寻找新的生物学标志物。     

Circulating tumor cells in the early detection of human cancers

Cancer is a severe disease with high morbidity and mortality globally. Thus, early detection is emerging as an important topic in modern oncology. Although the strategies for early detection have developed rapidly in recent decades, they remain challenging due to the subtle symptoms in the initial stage of the primary tumor. Currently, tumor biomarkers, imaging, and specific screening tests are widely used in various cancer types; however, each method has limitations. The harms are even overweight against the benefits in some cases. Therefore, early detection approaches should be improved urgently. Liquid biopsy, for now, is a convenient and non-invasive way compared to the traditional tissue biopsy in screening and early diagnosis. Circulating tumor cells (CTCs) are vital in liquid biopsy and play a central role in tumor dissemination and metastases. They have promising potential as cancer biomarkers in early detection. This review updates the knowledge of the biology of CTC; it also highlights the CTC enrichment technologies and their applications in the early detection of several human cancers.