The clinical significance of K-ras mutation in endometrial "surface epithelial changes" and their associated endometrial adenocarcinoma

A 2-tier subdivision of papillary proliferations of the endometrium (PPE) only emphasizing the complexity of papillae precisely predicts the neoplastic risk and reflects the neoplasia-related molecular characteristics-a single-centered analysis of 207 cases

Papillary proliferation of the endometrium (PPE) is subdivided based on the complexity of the papillae and the proliferation of lesions, and the complex group is considered to have an increased risk of concurrent/subsequent endometrial neoplasia. However, the current subdivision criteria fail to prove the equivalence of the quantity of simple papillae and structural complexity. In this study, we divided PPE of 207 cases from 2014 to 2022 into 3 groups according to structural complexity and proliferation degrees: Group 1 equaled to the simple PPE with a simple papillary structure and typical localized proliferation; group 2 had the simple structure similar to group 1 but occupy over 50% of the endometrial polyp or > 2 lesions in the surface of nonpolypoid endometrium; group 3 had the truly complex branching papillae despite of its proportion. Group 3 was implicated with significantly more concurrent endometrial neoplasia (EAH and carcinoma) compared with groups 1 and 2 (P < 0.01), while no difference was found between groups 1 and 2. In 128 cases with no concurrent endometrial abnormalities in the initial biopsy or curettage specimens, 4 cases presented endometrial neoplasia (3 carcinoma and 1 atypical hyperplasia) in the subsequent specimens, all of which presented PPE of group 3 but not group 1 or 2 in the prior tissues (P < 0.01). The immunochemistry of 83 cases showed similar expressions of ER, PTEN, ARID1A, PTEN, p16, β-catenin, and p53 between PPE and the surrounding normal endometrium. Nearly 100% of PPE cases lost expressions of PR. A total of 2/83 cases showing PAX2 expression were all in the group 3 and correlated with endometrial neoplasia (2/17, 11.76%, P < 0.05). 76/83 (91.57%) of PPE lesions had KRAS mutations, and the distributions of which were similar among 3 groups. The frequency of mucinous metaplasia was significantly higher in the PPE lesions with KRAS mutations (72/74, 97.30%, P < 0.01). Group 3 showed higher frequency of single KRAS mutations compared with the combination of groups 1 and 2 (P < 0.01). Finally, the concordance of KRAS mutation profiles between PPE and endometrial neoplasia was significantly higher in group 3 than either group 1 or 2 (P < 0.01), while no difference was found between group 1 and 2. Thus, a new 2-tier subdivision system only emphasizing the complexity of papillae is recommended, which might precisely predict the risk of endometrial neoplasia and neoplasia-related molecular characteristics.

LINC01354/microRNA-216b/KRAS Axis Promotes the Occurrence and Metastasis of Endometrial Cancer

OBJECTIVE

LINC01354 has been defined as a tumor driver in several cancers. Nevertheless, whether LINC01354 involves in endometrial cancer (EC) has been little navigated. Thus, the mechanism of LINC01354 was explored in the disease.

METHODS

Measurements of LINC01354, microRNA (miR)-216b and kirsten rat sarcoma viral oncogene (KRAS) levels in EC tissues and cells were performed. LINC01354 low expression and miR-216b overexpression vectors were introduced into EC cells (lshikawa), thereby their effects on cell viability, apoptosis, migration and invasion were manifested. Rescue experiments were also carried out by down-regulating LINC01354 and miR-216b spontaneously. Tumorigenesis in vivo was also assessed. The relationships of LINC01354/miR-216b/KRAS were analyzed.

RESULTS

Increased LINC01354 and KRAS and reduced miR-216b levels were measured in EC. Silencing LINC01354 or overexpressing miR-216b retarded EC cellular development. LINC01354 counteracted with miR-216b to target KRAS. Suppression of miR-216b antagonized silenced LINC01354-induced impacts on EC cell development. LINC01354/miR-216b/KRAS axis enhanced tumorigenesis in mice with EC.

CONCLUSION

It is testified that silencing LINC01354 inhibits KRAS by up-regulating miR-216b, thereby discouraging cell malignant phenotype in EC.

The Advance and Correlation of KRAS Mutation With the Fertility-Preservation Treatment of Endometrial Cancer in the Background of Molecular Classification Application

The annually increasing incidence of endometrial cancer in younger women has created a growing demand for fertility preservation. However, the diverse therapeutic efficacy among patients under the same histological subtype and the same tumor grade suggests the potential interference of the innate molecular characteristics. The molecular classification has now been applied in clinical practice and might help to stratify the endometrial cancer patients and individualize the therapy, but the candidates for the fertility-spared treatment are most likely to be subdivided in the subgroup lacking the specific signature. KRAS mutation has been linked to the malignant transition of the endometrium, while its role in molecular classification and fertility preservation is vague. Here, we mainly review the advance of molecular classification and the role of KRAS in endometrial cancer, as well as their correlation with fertility-preservation treatment.

Targeting mutated GTPase KRAS in tumor therapies

Kirsten rat sarcoma virus oncogene (KRAS) mutation accounts for approximately 85% of RAS-driven cancers, and participates in multiple signaling pathways and mediates cell proliferation, differentiation and metabolism. KRAS has been considered as an "undruggable" target due to the lack of effective direct inhibitors, although high frequency of KRAS mutations have been identified in multiple carcinomas in the past decades. Encouragingly, the KRAS^G12C inhibitor AMG510 (sotorasib), which has been approved for treating NSCLC and CRC recently, makes directly targeting KRAS the most promising strategy for cancer therapy. To better understand the current state of KRAS inhibitors, this review summarizes the biological functions of KRAS, the structure-activity relationship studies of the small-molecule inhibitors that directly target KRAS, and highlights the therapeutic agents with improved selectivity, bioavailability and physicochemical properties. Furthermore, the combined medication that can enhance efficacy and overcome drug resistance of KRAS covalent inhibitors is also reviewed.

Endometrial Adenocarcinomas With Significant Mucinous Differentiation: A Characterization of Intratumoral Heterogeneity of KRAS Mutations in Mucinous and Endometrioid Histologic Components

OBJECTIVE

KRAS mutations are frequently seen in malignancies with mucinous morphology. In our previous study, mucinous endometrial carcinomas were associated with a significantly higher frequency of KRAS mutations as compared with matched conventional endometrioid carcinomas. This study expands our previous report by exploring possible intratumoral heterogeneity for KRAS gene mutations in the mucinous components of mucinous carcinomas (MCs) and endometrioid carcinomas with significant mucinous differentiation (ECSMD) versus their associated "usual" endometrioid components.

MATERIALS AND METHODS

KRAS-positive cases from our previous report were studied, including 10 MCs and 10 ECSMDs. The specimens were microscopically dissected to separately isolate morphologically mucinous and endometrioid components. Direct DNA sequencing for KRAS mutations at codons 12 and 13 using capillary electrophoresis were performed.

RESULTS

KRAS mutations were detected in the endometrioid components of 8 (80%) of 10 MCs and 3 (30%) of 10 ECSMDs. The endometrioid component of the ECSMD group was less frequently associated with KRAS mutation than the endometrioid component of the MC group, even when the mucinous component of the same tumor contained a mutation; the difference is statistically significant (P < 0.05).

CONCLUSIONS

Our current study shows that intratumoral heterogeneity for KRAS gene mutation was associated with ECSMD, but less frequently with MC. It is possible that when the mucinous component predominates, qualifying for an MC, KRAS mutations appear to be widespread, irrespective of the mucinous or nonmucinous differentiation of the tumor cells. The findings suggest that multiple samples for KRAS tests may be useful, especially in endometrioid carcinoma with significant mucinous differentiation.

Genetic aberrations of the K-ras proto-oncogene in bladder cancer in relation to pesticide exposure

In Egypt, bladder cancer is one of the most popular cancers, accounting for 31% of all cancer cases. It ranks first in males about 16.2% of male cancer. The incidence in rural areas among males is near 32 per 100,000. The exact etiology of bladder cancer is still unknown; K-ras gene is known as a critical DNA target for chemical carcinogens such as pesticide. Some occupational hazard exposure is thought to be directly genotoxic, while others might enhance the mutagenicity and carcinogenicity of directly acting genotoxic agents. Analysis of the relationship between pesticide exposure and mutation in the K-ras gene in human bladder cancer. One hundred patients were diagnosed with bladder cancer and two hundred controls attended the outpatient clinic; after taking consent and filling a questionnaire for age, sex, occupation and pesticide exposure, surgically resected specimens were collected and the samples were used to determine the k-ras mutation. Blood samples were taken to analyze the level of acetylcholinesterase enzyme and level of P₅₃. The present study indicated that pesticide exposure may play a great role in malignant transformation of the bladder cells through mutation in the K-ras gene; there was a significant correlation between the acetylcholinesterase enzyme level and k-ras mutation (p < 0.001). The results revealed that the level of P₅₃ was significantly high in comparison with the control group (p < 0.001). These findings give an alarm to decrease the amount of pesticides used in our area; also, p₅₃ may be used as an indicator to bladder cancer.

KRAS/BRAF基因与结肠癌糖代谢研究现状

正电子发射断层成像术(positron emission tomography, PET)/计算机断层扫描(computed tomography, CT)显像可用于结肠癌的诊断、监测疗效和预后评估. ¹⁸F标记葡萄糖(2-fluorine-18-fluoro-2-deeoxy-D-glucose, ¹⁸F-FDG)是PET/CT常用显像剂, 可以反映结肠癌活体组织葡萄糖代谢. KRAS/BRAF基因检测常用于结肠癌靶向治疗方案的选择及评估其治疗效果. 文献报道¹⁸F-FDG-PET/CT显像可预测结肠癌KRAS/BRAF基因状态, 能以无创的方式预测结肠癌抗表皮生长因子受体靶向治疗效果. 目前国内有关KRAS/BRAF基因与结肠癌糖代谢的研究相对较少, 本文结合近期的相关文献进行概述.