Absence of GNAS Mutation in Colorectal Carcinogenesis

A GNAS Gene Mutation's Independent Expression in the Growth of Colorectal Cancer: A Systematic Review and Meta-Analysis

Globally, colorectal carcinoma CRC is the third most common cancer and the third most common reason for cancer-associated mortality in both genders. The GNAS mutations are significantly linked with poor prognosis and failed treatment outcomes in CRC. A systematic review and meta-analysis of multiple studies executed following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria and registered with PROSPERO (registration number: CRD42021256452). The initial search includes a total of 271 publications; however, only 30 studies that merit the eligibility criteria were eventually chosen. Data analysis via OpenMeta Analyst and comprehensive meta-analysis 3.0 (CMA 3.0) software were used to investigate the prevalence of GNAS gene mutation among CRC patients. The meta-analysis consisted of 10,689 participants with most being males 6068/10,689 (56.8%). Overall, prevalence of GNAS mutations was 4.8% (95% CI: 3.1−7.3) with I2 = 94.39% and (p < 0.001). In 11/30 studies, the frequency of GNAS gene mutations was majorly in codons R201C [40.7% (95% CI: 29.2−53.2%)] and in codon R201H [39.7% (95% CI = 27.1−53.8)]. Overall prevalence of GNAS mutations was highest among the male gender: 53.9% (95% CI: 48.2−59.5%: I2 = 94.00%, (p < 0.001), tumour location (colon): 50.5% (95% CI: 33.2−67.6%: I2 = 97.93%, (p < 0.001), tumour grade (Well): 57.5% (95% CI: 32.4−79.2%: I2 = 98.10%, (p < 0.001) and tumour late stage: 67.9% (95% CI: 49.7−84.3%: I2 = 98.%, (p < 0.001). When stratified according to study location, a higher prevalence was observed in Japan (26.8%) while Italy has the lowest (0.4%). Overall prevalence of GNAS gene mutations was 4.8% with codons R201C and R201H being the most mutated, and the results conformed with numerous published studies on GNAS mutation.

CircRNAs: A New Chapter in Oral Squamous Cell Carcinoma Biology

With the rapid development of bioinformatics and gene sequencing technologies, understanding of circular RNAs (circRNAs) has been extended, and numerous studies have identified the key regulator role of circRNAs in a variety of diseases, especially in cancer. Recently, accumulated studies of oral squamous cell carcinoma (OSCC) have discovered the great potential of circRNAs, which can serve as prognostic or diagnostic biomarkers and affect the development and therapy of OSCC. In this review, we detail the new progress of circRNA research for OSCC in order to provide new strategies for clinical diagnosis and treatment.

GNAS mutations are present in colorectal traditional serrated adenomas, serrated tubulovillous adenomas and serrated adenocarcinomas with adverse prognostic features

AIMS

Activating mutations in GNAS are important in the development of a range of neoplasms, including a small proportion of conventional adenomas and colorectal carcinomas (CRCs). However, their contribution to serrated pathway neoplasia is unclear, as mutations have only been examined in small series of sessile serrated adenomas (SSAs) and traditional serrated adenomas (TSAs), and not in serrated tubulovillous adenomas (sTVAs). The aim of this study was to investigate the frequency and significance of GNAS mutations in colorectal adenomas and CRCs.

METHODS AND RESULTS

Using a large, well-characterized series, we identified GNAS mutations in 9.2% (18 of 196) of TSAs, 7.1% (four of 56) of sTVAs and 2.0% (nine of 459) of CRCs. Mutations were absent in SSAs (none of 43), tubular adenomas (none of 50) and conventional tubulovillous adenomas (none of 50). A BRAF or KRAS mutation was seen in 77.4% of GNAS mutant lesions, suggesting a synergistic effect with the mitogen-activated protein kinase pathway. In CRCs, GNAS mutations were associated with mucinous differentiation and serrated morphological features.

CONCLUSIONS

GNAS mutations contribute significantly to the development of a subset of serrated adenomas and CRCs.