Promoter Hypermethylation of LATS1 Gene in Oral Squamous Cell Carcinoma (OSCC) among North Indian Population

Investigating Tobacco's Impact on DNA Repair Genes and Risks in Oral Precancer and Cancer: A Comprehensive Research Study

Objective

This study aimed to explore genetic variations associated with DNA repair mechanisms to enhance the management of both oral cancer (OC) and oral precancer (OPC).

Methods

A cohort of 380 patients diagnosed with OC and OPC, comprising 220 males and 160 females, was analyzed. Participants were categorized based on their tobacco-chewing habits, with corresponding control groups established. Key genetic markers investigated for polymorphisms included OGG1, APE1, and XRCC1.

Results

The XRCC1 Arg280H variant demonstrated significant associations with the susceptibility to both OC and OPC across various models. Further analyses, incorporating factors such as tobacco and alcohol consumption, unveiled a correlation between the XRCC1 Arg194Trp variant and an elevated risk of developing head and neck cancer. Stratified analyses also revealed an increased risk of OC or OPC based on the specific site of the cancer.

Conclusion

The study underscores the importance of XRCC1 polymorphisms, particularly XRCC1 Arg280H and XRCC1 Arg194Trp, within the genetic framework of OC and OPC. Understanding these genetic associations provides valuable insights for the potential development of targeted interventions aimed at individuals predisposed to these conditions.

Oral tumor heterogeneity, its implications for patient monitoring and designing anti-cancer strategies

Oral cancer tumors occur in the mouth and are mainly derived from oral mucosa linings. It is one of the most common and fatal malignant diseases worldwide. The intratumor heterogeneity (ITH) of oral cancerous tumor is vast, so it is challenging to study and interpret. Due to environmental selection pressures, ITH arises through diverse genetic, epigenetic, and metabolic alterations. The ITH also talks about peri-tumoral vascular/ lymphatic growth, perineural permeation, tumor necrosis, invasion, and clonal expansion/ the coexistence of multiple subclones in a single tumor. The heterogeneity offers tumors the adaptability to survive, induce growth/ metastasis, and, most importantly, escape antitumor therapy. Unfortunately, the ITH is prioritized less in determining disease pathology than the traditional TNM classifications or tumor grade. Understanding ITH is challenging, but with the advancement of technology, this ITH can be decoded. Tumor genomics, proteomics, metabolomics, and other modern analyses can provide vast information. This information in clinics can assist in understanding a tumor's severity and be used for diagnostic, prognostic, and therapeutic decision-making. Lastly, the oral tumor ITH can lead to individualized, targeted therapy strategies fighting against OC.

MicroRNAs targeting CDKN2A gene as a potential prognostic marker in head and neck squamous cell carcinoma

Epigenetic factors are known to markedly influence the functions of a gene by modification of transcripts, via methylation or acetylation and degradation of mRNA transcripts. The CDKN2A encodes cyclin-dependent kinase inhibitor 2A, a tumour suppressor protein. Genetic and epigenetic alterations in this gene have been demonstrated in several cancer types. The non-coding RNAs with a special emphasis on microRNAs have long been explored for their potential role in the epigenetic modification of gene expression. The present study aims to identify the microRNAs targeting CDKN2A gene transcripts and demonstrate their prognostic significance in head and neck squamous cell carcinoma (HNSCC). Computational approaches were employed to identify the microRNAs targeting CDKN2A. The gene and protein expression profile of CDKN2A was analyzed using UALCAN. A significant upregulation of CDKN2A was observed in the primary tumour tissues (p=<10-12). Interestingly, the protein expression, although found to be statistically significant (p=0.0129) did not correlate well with the gene expression profile. The microRNAs targeting CDKN2A were further analyzed to identify the possible reason for the decrease in protein expression. Among the 44 microRNAs targeting CDKN2A gene transcripts, hsa-miR-3681-3p, hsa-miR-542-5p, hsa-miR-4519 were found to be upregulated and hsa-miR-134-5p was found to be downregulated with a significant association with survival status of HNSCC patients. The hsa-miR-542-5p was found to correlate well with the survival and hence can be considered as the key microRNA associated with HNSCC. However, further validation of this microRNA is warranted to confirm its role in the process of carcinogenesis.

Downregulation of zinc finger protein 71 expression in oral squamous cell carcinoma tissues and its underlying molecular mechanism

BACKGROUND

Patients with oral squamous cell carcinoma (OSCC) have poor prognoses due to a limited understanding of the pathogenesis of OSCC. Zinc finger protein (ZNF) is the largest transcription factor family in the human genome and exert diverse and important functions. Nevertheless, the exact expression status and molecular mechanism of ZNF71 have not been described in OSCC. Therefore, this study aimed to identify the specific expression level of ZNF71 in OSCC tissues and to further interpret the potential molecular mechanism of ZNF71 in the pathogenesis of OSCC.

METHODS

In-house immunohistochemical staining of 116 OSCC samples and 29 non-OSCC samples was employed to detect the expression status of ZNF71 at the protein level of OSCC tissues. Single-cell RNA sequencing data from 7 OSCC samples was used to explore the expression landscape of ZNF71 in different cell types from OSCC tissues. High-throughput RNA sequencing data and gene chips data from 893 OSCC samples and 301 non-OSCC samples were utilized to identify the specific expression level of ZNF71 at the bulk mRNA level of OSCC tissues. Here, standardized mean difference (SMD) value was applied to calculate the expression differences between OSCC group and non-OSCC group. Multiple datasets were included; hence, the results were considered to be more reliable. Sensitivity analysis was conducted to evaluate the stability of the results. Enrichment analysis and immune infiltration analysis were used to explore the underlying molecular mechanism of ZNF71 in OSCC.

RESULTS

ZNF71 was significantly downregulated in OSCC tissues at the protein level (SMD = -1.96, 95 % confidence interval [95 % CI]: -2.43 to -1.50). ZNF71 was absent in various cell types from OSCC tissues including cancerous epithelial cells and tumor-infiltrating immune cells. ZNF71 was downregulated in OSCC tissues at the bulk mRNA level (SMD = -0.38, 95 % CI: -0.75 to -0.02). Enrichment analysis showed that positively and differentially co-expressed genes mainly concentrated on "herpes simplex virus 1 infection" and "regulation of plasma membrane bounded cell projection organization", and negatively and differentially co-expressed genes mainly participated in "cell cycle" and "DNA metabolic process". Moreover, the putative target genes of ZNF71 mainly participated in "cellular respiration" and "protein catabolic process". Finally, immune infiltration analysis revealed that ZNF71 expression was positively correlated with multiple immune cells including activated B cells, memory B cells, and natural killer (NK) cells, and negatively correlated with various immune cells, including CD56 bright NK cells, neutrophil, and immature dendritic cells.

CONCLUSION

The downregulation of ZNF71 may influence the initiation and promotion of OSCC by reducing immune infiltration, accelerating cell cycle progression, and affecting metabolic process, and this requires further research.

Hippo in Gastric Cancer: From Signalling to Therapy

The Hippo pathway is one of the most important ones in mammals. Its key functions in cell proliferation, tissue growth, repair, and homeostasis make it the most crucial one to be controlled. Many means have been deployed for its regulation, since this pathway is not only composed of core regulatory components, but it also communicates with and regulates various other pathways, making this signalisation even more complex. Its role in cancer has been studied more and more over the past few years, and it presents YAP/TAZ as the major oncogenic actors. In this review, we relate how vital this pathway is for different organs, and how regulatory mechanisms have been bypassed to lead to cancerous states. Most studies present an upregulation status of YAP/TAZ, and urge the need to target them. A focus is made here on gastric carcinogenesis, its main dysregulations, and the major strategies adopted and tested to counteract Hippo pathway disbalance in this disease. Hippo pathway targeting can be achieved by various means, which are described in this review. Many studies have tested different potential molecules, which are detailed hereby. Though not all tested in gastric cancer, they could represent a real interest.

Molecular and genomic landscapes in secondary & therapy related acute myeloid leukemia

Acute myeloid leukemia (AML) is a complex, aggressive myeloid neoplasm characterized by frequent somatic mutations that influence different functional categories' genes, resulting in maturational arrest and clonal expansion. AML can arise de novo (dn-AML) or can be secondary AML (s-AML) refers to a leukemic process which may arise from an antecedent hematologic disorder (AHD-AML), mostly from a myelodysplastic syndrome (MDS) or myeloproliferative neoplasm (MPN) or can be the result of an antecedent cytotoxic chemotherapy or radiation therapy (therapy-related AML, t-AML). Clinical and biological features in secondary and therapy-related AML are distinct from de novo AML. Secondary and therapy-related AML occurs mainly in the elderly population and responds worse to therapy with higher relapse rates due to resistance to cytotoxic chemotherapy. Over the last decade, advances in molecular genetics have disclosed the sub-clonal architecture of secondary and therapy-related AML. Recent investigations have revealed that cytogenetic abnormalities and underlying genetic aberrations (mutations) are likely to be significant factors dictating prognosis and critical impacts on treatment outcome. Secondary and therapy-related AML have a poorer outcome with adverse cytogenetic abnormalities and higher recurrences of unfavorable mutations compared to de novo AML. In this review, we present an overview of the clinical features of secondary and therapy-related AML and address the function of genetic mutations implicated in the pathogenesis of secondary leukemia. Detailed knowledge of the pathogenetic mechanisms gives an overview of new prognostic markers, including targetable mutations that will presumably lead to the designing and developing novel molecular targeted therapies for secondary and therapy-related AML. Despite significant advances in knowing the genetic aspect of secondary and therapy-related AML, its influence on the disease's pathophysiology, standard treatment prospects have not significantly evolved during the past three decades. Thus, we conclude this review by summarizing the modern and developing treatment strategies in secondary and therapy-related acute myeloid leukemia.