Advances in microRNAs as Emerging Biomarkers for Colorectal Cancer Early Detection and Diagnosis.

Colorectal cancer (CRC) remains the second most common cause of cancer-related mortality worldwide, necessitating advancements in early detection and innovative treatment strategies. MicroRNAs (miRNAs), small non-coding RNAs involved in gene regulation, have emerged as crucial players in the pathogenesis of CRC. This review synthesizes the latest findings on miRNA deregulated in precancerous lesions and in CRC. By examining the deregulation patterns of miRNAs across different stages of CRC development, this review highlights their potential as diagnostic tools. We specifically analyse the roles and diagnostic relevance of four miRNAs-miR-15b, miR-21, miR-31, and miR-146a-that consistently exhibit altered expression in CRC. The current knowledge of their role in key oncogenic pathways, drug resistance, and clinical relevance is discussed. Despite challenges posed by the heterogeneity of the research findings on miRNA deregulation and their role in CRC, integrating miRNA diagnostics into current screening methods holds promise for enhancing personalized medicine approaches. This review emphasizes the transformative potential of miRNAs in CRC diagnosis, paving the way for improved patient outcomes and novel therapeutic paradigms.

Prevalence and clinical implications of the HPV16 infection in oral cancer in Montenegro - Evidence to support the immunization program.

Oral squamous cell carcinoma (OSCC) makes 85-95% of all malignances in the oral cavity. Increasing evidence shows that the Human Papillomaviruses (HPVs) are preferentially associated with some oropharyngeal and OSCCs, namely the genotype 16. The aim of the present study was to determine the prevalence and clinical implications of HPV16 infection in oral squamous cell carcinoma in population of Montenegro.This study included 60 patients with OSCC (localized on the lower lip, tongue or/and floor of the mouth), surgically treated at the Clinical Centre of Montenegro from 2012 to 2018. Surgically obtained formalin-fixed and paraffin-embedded specimens were used for histopathological analysis and HPV16 genome detection using standard Polymerase Chain Reaction (primers for detection of E6 gene). Each individual was further followed up for the period of three years and for different clinico-pathological characteristics, including disease free interval (DFI).The prevalence of HPV16 infection in OSCCs was 23.3% and the infection was significantly more common in female patients (P = 0.038). No significant correlation was detectable between HPV16 infection and the patients' age (P = 0.302), tumor site (P = 0.125), tumor grade (P = 0.363) and disease stage (P = 0.995). Observing the total sample the DFI was not significantly different for HPV16-positive versus HPV16-negative patients (P = 0.427), but a gender-based difference in DFI was observed, with the significantly shorter DFI (Log Rank test, P = 0.003) in HPV16 positive female patients compared to male patients (P = 0.003).The results obtained in this study provide scientific evidence for the development of national HPV vaccination program in Montenegro.

Distribution of vaccine-related high-risk human papillomaviruses and their impact on the development of cervical dysplasia in women in Montenegro.

Cervical cancer (CC) is the third leading cause of death in women in Montenegro. Human papillomavirus (HPV) is the causative agent of CC however, HPV genotype distribution varies across regions. This study examined the distribution and impact of vaccine-related high-risk (HR)-HPVs on the development of cervical dysplasia in Montenegrin women. A total of 187 women who had a clinical indication for cervical biopsy were enrolled. Based on histopathological findings, women were classified into 2 groups, with and without dysplasia. HR-HPV was detected by real-time PCR. Twelve HR-HPV genotypes were detected in 40.6% of cervical samples. The 7 most prevalent HR-HPVs in order of decreasing frequency were HPV 16 (39.5%), 45 (23.7%), 31 (21.0%), 33 (17.1%), 18 (6.6%), 52 (6.6%), and 58 (6.6%), all of them are targeted by nonavalent vaccine. Vaccine-related HR-HPVs had a higher prevalence (92.1%) than the other HR-HPVs detected in HR-HPV-positive samples. Among HR-HPV-positive women, HPV 16 and 33 were more common in women with dysplasia than in those without dysplasia (HPV 16: 28.9 vs 7.2%; HPV 33: 11.8 vs 3.6%). HPV 16 was the most common HR-HPV genotype in cervical samples, followed by HPV 45, 31, 33, 18, 52, and 58. HPV 16 and 33 were shown to be associated with the development of cervical dysplasia. These results indicate that prophylactic nonavalent vaccine can potentially prevent approximately 90% of HR-HPV infections and 60% of cervical dysplasia cases in Montenegrin women.

miR-29a expression negatively correlates with Bcl-2 levels in colorectal cancer and is correlated with better prognosis.

MicroRNAs (miRNAs) are a class of small non-coding RNAs that act as important regulators of gene expression, involved in various biological pathways. Aberrant miRNAs expression is associated with the onset and progression of colorectal cancer (CRC). The aim of this study was to investigate the correlation between five miRNAs (miR-29a, miR-101, miR-125b, miR-146a, and miR-155), found to be deregulated in tissue samples of CRC patients, and clinicopathological characteristics and histological markers. Analysis of histological markers was performed by immunohistochemical staining of tumour tissues with Ki-67, p53, CD34, and Bcl-2. Our findings revealed a significant negative correlation between miR-29a expression and Bcl-2 levels. Furthermore, high miR-29a expression was associated with a lower incidence of distant metastasis in CRC patients. We observed negative correlations between miR-101 expression and the number of lymph nodes with metastasis, as well as the size of the largest metastasis; miR-125b expression and lymphovascular invasion; and miR-155 expression and mucus presence. Our survival analysis demonstrated that high miR-29a expression correlated with better progression-free survival of CRC patients, underscoring its potential as a prognostic marker. Our study unveiled intricate relationships between specific miRNA expressions and clinicopathological features in CRC, highlighting the potential utility of miR-29a as a valuable prognostic biomarker.

Correlation between stromal Th and Tc lymphocytes and PD-L1 expression in early breast cancer tumors.

INTRODUCTION: Prognostic and predictive value of PD-L1 as a biomarker in breast cancer remains controversial. While some studies suggest its association with negative prognostic parameters, others reported a highly significant association between PD-L1 expression and tumor-infiltrating lymphocytes, which are known to be an independent favorable prognostic factor. The aim of present study is to examine the relationship between immune response markers and PD-L1 expression in early breast cancer. MATERIAL AND METHODS: Immunohistochemical expression of PD-L1, along with density and composition of stromal lymphocytic infiltrate and peritumoral lymphoid aggregates was analyzed in 95 samples of invasive breast cancer. RESULTS: A strong positive correlation between PD-L1 expression and the density of stromal lymphocytic infiltrate and peritumoral lymphoid aggregates was identified and a cut-off value of 53% coverage of tumor stroma by lymphocytes, with which PD-L1 positivity can be predicted with excellent diagnostic accuracy, was determined for the first time using statistical methods. Additionally, PD-L1 positivity was observed significantly more often in tumors with higher absolute number of both CD4 and CD8 T-lymphocytes in the stromal infiltrate. No significant correlation with molecular subtype of breast cancer was found. CONCLUSIONS: Our results indicate that the density of stromal lymphocytic infiltrate might be a better predictor of PD-L1 positivity in early breast cancer than the molecular subtype and that the key to the optimization of PD-L1 as a biomarker in breast cancer lies in its interpretation in the context of other immune response markers.

The role of miRNA in colorectal cancer diagnosis: A pilot study.

Despite recent advances in diagnosis and treatment, colorectal cancer (CRC) remains the third most common cancer worldwide, and has both a poor prognosis and a high recurrence rate, thus indicating the need for new, sensitive and specific biomarkers. MicroRNAs (miRNAs/miRs) are important regulators of gene expression, which are involved in numerous biological processes implicated in tumorigenesis. The objective of the present study was to investigate the expression of miRNAs in plasma and tissue samples from patients with CRC, and to examine their potential as CRC biomarkers. Using reverse transcription-quantitative PCR, it was revealed that miR-29a, miR-101, miR-125b, miR-146a and miR-155 were dysregulated in the formalin-fixed paraffin-embedded tissues of patients with CRC, compared with the surrounding healthy tissue, and these miRNAs were associated with several pathological features of the tumor. Bioinformatics analysis of overlapping target genes identified AGE-RAGE signaling as a putative joint regulatory pathway. miR-146a was also upregulated in the plasma of patients with CRC, compared with the healthy control group, and had a fair discriminatory power (area under the curve, 0.7006), with 66.7% sensitivity and 77.8% specificity. To the best of our knowledge, this distinct five-miRNA deregulation pattern in tumor tissue, and upregulation of plasma miR-146a, were shown for the first time in patients with CRC; however, studies on larger patient cohorts are warranted to confirm their potential to be used as CRC diagnostic biomarkers.

Time course and expression pattern of the neuronal markers in the developing human spinal cord.

The aim of this study was to examine the spatio-temporal appearance of different neuronal cell subtypes by analyzing expression patterns of several neuronal markers (calretinin, neurofilament 200 (NF200), vanilloid receptor 1(VR1) and calcitonin gene-related peptide (CGRP)) of the embryonic human spinal cord (SC). Developing human SCs from 11 human conceptuses beetwen 5-10 developmental weeks (DW) were examined by light and electron microscopy and immunofluorescence. Light and electron microscopy revealed different embryonic stages of recognizable structure of the SC. NF200, CGRP and VR1 positive cells were observed in SCs during 5th-6th DW. NF200 was predominantly expressed in the ventral part, indicating presence of motoneurons. As development advanced, NF200 was mainly expressed in the marginal zone. Expression of CGRP was intense during all of the investigated periods, predominantly during the 5th-6th DW pointing to neural sensory differentiation, as opposed to the last DW when reduced expression of CGRP in the marginal layer indicated the terminations of the sensory afferents. Expression of VR1 was highest in the intermediate zone, at the beginning and at the end of the investigated periods, pointing to VR1 spatial pattern in the visceral afferents in the grey matter, while the first signs of calretinin were found in the 9th-10th DW ventrally. Delineating the relationships between factors involved in processes of neuronal differentiation as well as spatial and temporal arrangement of SC interrelated neurons can provide a useful information about normal SC development as well as the insight in possible causes of anomalies and disorders during embryonic life.

Tachycardia in a newborn with enterovirus infection.

Enterovirus infections are common in the neonatal period. Newborns are at a higher risk of severe disease including meningoencephalitis, sepsis syndrome, cardiovascular collapse, or hepatitis. The mechanism of heart failure in patients with enterovirus infection remains unknown. Early diagnosis may help clinicians predict complications in those infants initially presenting with severe disease. An 11-day-old male newborn was admitted to our neonatal intensive care unit because of tachycardia and crises of cyanosis. His elder brother had febrile illness. The newborn was cyanotic, in respiratory distress, with tachycardia, low blood pressure and prolonged capillary refilling time. Limb pulse oximeter was around 85%. During the first day of hospitalization, the newborn had one febrile episode. Laboratory data: elevated transaminases, markers of inflammation negative, all bacterial cultures negative. Enterovirus RNA was detected in blood sample. Other blood findings were without significant abnormalities. Electrocardiogram showed tachycardia, with narrow QRS complexes (atrial tachycardia) and heart rate up to 280/min. In order to convert the rhythm, the patient was administered adenosine and amiodarone. In the further course of hospitalization, the patient was in good general condition, eucardiac and eupneic. Newborns with tachycardia and a family history of febrile illness should be suspected to have enterovirus infection. Enterovirus infection is a highly contagious and potentially life-threatening infection if not detected early. The use of sensitive molecular-based amplification methods offers potential benefits for early diagnosis and timely treatment.