K-ras gene mutation analysis to diagnosis pancreatic adenocarcinoma from endoscopic ultrasound-guided tissue acquisition; a systematic review and meta-analysis.

BACKGROUND: Endoscopic ultrasound-guided tissue acquisition (EUS-TA) has high sensitivity for the pathological diagnosis of pancreatic masses, but also a high false-negative rate. K-ras gene mutations occur in over 75 % of pancreatic ductal adenocarcinomas (PDAC), and this meta-analysis evaluated the utility of detecting K-ras gene mutations from EUS-TA specimens for the diagnosis of PDAC. METHODS: Relevant studies in PubMed, the Cochrane Library, and Web of Science were systematically searched. Meta-analysis was performed on data from the selected studies using a bivariate model to provide pooled values of sensitivity, specificity, and their 95 % confidence intervals (CIs). RESULTS: This meta-analysis included 1521 patients (from 10 eligible studies) who underwent EUS-TA with K-ras gene mutation analysis for diagnosis of pancreatic solid masses. The pooled estimates of sensitivity and specificity were 76.6 % (95 % CI, 70.9-81.5 %) and 97.0 % (95 % CI, 94.0-98.5 %), respectively, for pathological diagnosis, 75.9 % (95 % CI 69.5-81.4 %) and 95.3 % (95 % CI, 92.3-97.2 %) for K-ras gene mutation analysis, and 88.7 % (95 % CI 87.1-91.7 %) and 94.9 % (95 % CI, 91.5-97.0 %) for pathological diagnosis in combination with K-ras gene mutation analysis. The sensitivity for diagnosis of PDAC was significantly higher for pathological diagnosis in combination with K-ras gene mutation analysis than for pathological diagnosis or K-ras gene mutation analysis alone (both, p < 0.001). There was no difference in specificity between pathological diagnosis in combination with K-ras gene mutation analysis and both either (p = 0.234, 0.945, respectively). CONCLUSIONS: K-ras gene mutation analysis in combination with to pathological diagnosis of EUS-TA increases the accuracy of differential diagnosis of PDAC.

Proteomic characteristics of PM2.5-induced differentially expressed proteins in k-ras-silenced HBE cells.

The human bronchial epithelial cells (HBE) and K-ras-silenced HBE cells were treated with fine particulate matter (PM2.5) samples from Taiyuan for 24 h. To screen the proteomic characteristics of PM2.5-induced differentially expressed proteins (DEPs), the Q Exactive mass spectrometer was used. Gene ontology (GO) analysis, Kyoto encyclopedia of genes and genomes (KEGG) analysis, functional prediction, protein-protein interaction (PPI) network analysis, and visualization of differential protein interactions were performed. 251 DEPs in K-ras silenced cells and 535 DEPs in normal HBE cells were identified, respectively. KEGG analysis showed that the differentially expressed proteins of PM2.5-treated cells were related to the biosynthesis of ribosomes, antibiotics, and amino acids. On the other hand, K-ras silenced cells were related to metabolic pathways, RNA transport, and DNA replication. Through the construction of a PPI network, the top 10 hub proteins were screened from the two cell groups, among which MRPL13, RPS20, and EIF1AX were of great significance. Our results indicated that the K-ras gene plays an important role in PM2.5-induced DEPs, and the findings provide a scientific basis for the further study of PM2.5 toxic mechanisms and biomarkers.

Detection of RAS gene mutation and its clinical significance in children with acute lymphoblastic leukemia. / å„¿ç«¥æ€¥æ€§æ·‹å·´ç»†èƒžç™½è¡€ç— ä¸­RASåŸºå› çªå˜çš„æ£€æµ‹åŠå ¶ä¸´åºŠæ„ä¹‰.

OBJECTIVES: To investigate the mutation rate of the RAS gene and its clinical significance in children with acute lymphoblastic leukemia. METHODS: A retrospective analysis was performed on the medical data of 120 children with newly diagnosed acute lymphoblastic leukemia, who were admitted to the Third Affiliated Hospital of Zhengzhou University from January 2015 to January 2020 and underwent next-generation sequencing. The clinical and molecular features were analyzed. The impact of RAS gene mutation on the overall survival rate was evaluated in these children. RESULTS: Among the 120 children, 35 (29.2%) had RAS gene mutation, 30 (25.0%) had KRAS gene mutation, and 5 (4.2%) had both NRAS and KRAS gene mutations. All NRAS mutations and 71% (25/35) of KRAS mutations were located at the 12th and 13th codons. RAS gene mutation was detected in 35 (33.3%) out of 105 children with B-lineage acute lymphoblastic leukemia, but it was not detected in those with acute T lymphocyte leukemia. Of all the children, 11 (9.2%) were lost to follow-up, and among the 109 children followed up, 16 (14.7%) died. The children with RAS gene mutation had a significantly lower 2-year overall survival rate than those without RAS gene mutation (P<0.05). The prognosis of children with RAS gene mutation combined with WT1 overexpression and WBC>50×109/L at diagnosis was worse (P<0.05). CONCLUSIONS: RAS gene mutation is commonly observed in children with B-lineage acute lymphoblastic leukemia and may have an adverse effect on prognosis.

Molecules linked to Ras signaling as therapeutic targets in cardiac pathologies.

The Ras family of small Guanosine Triphosphate (GTP)-binding proteins (G proteins) represents one of the main components of intracellular signal transduction required for normal cardiac growth, but is also critically involved in the development of cardiac hypertrophy and heart failure. The present review provides an update on the role of the H-, K- and N-Ras genes and their related pathways in cardiac diseases. We focus on cardiac hypertrophy and heart failure, where Ras has been studied the most. We also review other cardiac diseases, like genetic disorders related to Ras. The scope of the review extends from fundamental concepts to therapeutic applications. Although the three Ras genes have a nearly identical primary structure, there are important functional differences between them: H-Ras mainly regulates cardiomyocyte size, whereas K-Ras regulates cardiomyocyte proliferation. N-Ras is the least studied in cardiac cells and is less associated to cardiac defects. Clinically, oncogenic H-Ras causes Costello syndrome and facio-cutaneous-skeletal syndromes with hypertrophic cardiomyopathy and arrhythmias. On the other hand, oncogenic K-Ras and alterations of other genes of the Ras-Mitogen-Activated Protein Kinase (MAPK) pathway, like Raf, cause Noonan syndrome and cardio-facio-cutaneous syndromes characterized by cardiac hypertrophy and septal defects. We further review the modulation by Ras of key signaling pathways in the cardiomyocyte, including: (i) the classical Ras-Raf-MAPK pathway, which leads to a more physiological form of cardiac hypertrophy; as well as other pathways associated with pathological cardiac hypertrophy, like (ii) The SAPK (stress activated protein kinase) pathways p38 and JNK; and (iii) The alternative pathway Raf-Calcineurin-Nuclear Factor of Activated T cells (NFAT). Genetic alterations of Ras isoforms or of genes in the Ras-MAPK pathway result in Ras-opathies, conditions frequently associated with cardiac hypertrophy or septal defects among other cardiac diseases. Several studies underline the potential role of H- and K-Ras as a hinge between physiological and pathological cardiac hypertrophy, and as potential therapeutic targets in cardiac hypertrophy and failure.

Clinical relevance of H-RAS, K-RAS, and N-RAS mRNA expression in primary breast cancer patients.

PURPOSE: The RAS family comprises three proto-oncogenes (H-RAS, K-RAS, and N-RAS) and is among the most widely studied of oncogenes. The present study aimed at investigating the clinical relevance of mRNA levels of the three isoforms in a large group of breast cancer patients with a long-term follow-up. METHODS: 198 previously untreated patients were enrolled in the study. mRNA levels of K-RAS, H-RAS, and N-RAS were measured using microarray (Affymetrix HG-U133A). RESULTS: Elevated H-RAS levels were found significantly more frequently in patients with larger (p = 0.021) and ER-positive tumors (p = 0.048), while elevated K-RAS levels were associated with nodal positivity (p = 0.001) and HER2-positivity (p = 0.010). Patients with high N-RAS mRNA levels were more likely to be diagnosed with triple-negativity (p < 0.001) and higher grading (p = 0.001). Patients with high K-RAS levels were more likely to show an elevated H-RAS (p = 0.003). After a median follow-up of 183 months, patients with high N-RAS expression had significantly reduced overall survival (OS) compared with patients with low N-RAS (mean: 146.9 vs. 211.0 months; median 169.3 vs. not reached; p = 0.009). In patients with non-metastatic disease at the time of tissue sampling, mean disease-free survival (DFS) was 150.1 months for patients with high N-RAS versus 227.7 months with low N-RAS; median DFS was not reached (p = 0.004). The expression of H-RAS and K-RAS was not associated with DFS/OS. In the multivariable analysis, distant metastasis, HER2 positivity, and elevated N-RAS mRNA levels independently predicted reduced OS, while nodal status, HER2 status, and N-RAS predicted reduced DFS. CONCLUSIONS: Elevated N-RAS mRNA levels predict impaired clinical outcome; hypothetically, further exploration of the RAS signaling pathway might enable identifying potential targeted treatment strategies. The association between high N-RAS levels and the most aggressive among breast cancer subtypes, the triple-negative phenotype, for which targeted approaches are still lacking, underlines the need to further investigate the RAS family.

An Analysis of Relationship Between RAS Mutations and Prognosis of Primary Tumour Resection for Metastatic Colorectal Cancer Patients.

BACKGROUND/AIMS: Non-radical primary tumour resection (PTR) of asymptomatic metastatic colorectal cancer (mCRC) can prolong survival time of some patients. Patients with mutated RAS gene have worse survival outcome. This study aimed to investigate the impact of RAS gene mutations on the prognosis of asymptomatic unresectable mCRC patients who underwent PTR. METHODS: A retrospective observational cohort study was deduced among mCRC patients who experienced PTR or had intact primary tumour (IPT). All of them had the primary tumour tissue genotyping tested for RAS (KRAS and NRAS) gene mutations. The tumour-related overall survival (OS) time and progression-free survival (PFS) time was estimated. From January 2011 to June 2014, 421 mCRC patients with asymptomatic, unresectable, metastatic disease were enrolled in this study. Among them, 282 patients underwent PTR and 139 patients had IPT. RESULTS: The mutation rate of RAS was 53.8% (221/411). With a median followed-up time of 46.5 months, the overall survival time of mCRC patients harboring wtRAS or mtRAS was 28.0 versus 22.0 months (p = 0.043) in PTR group and was 21.6 versus 17.8 months (p=0.071) in IPT groups. A Multivariate regression analysis suggested that RAS gene (p=0.039, HR=1.288,95%CI [1.072∼2.911]), metastatic organ number (p=0.033, HR=3.091,95%CI [1.090∼5.755]) and systemic therapy response (p=0.019, HR=0.622,95%CI [0.525∼0.811]) were independent prognostic factors in PTR population. CONCLUSION: We found that wild-type RAS gene was a favorable factor for the asymptomatic unresectable mCRC patients experiencing PTR.

Electrochemical biosensor based on functional composite nanofibers for detection of K-ras gene via multiple signal amplification strategy.

An electrochemical biosensor based on functional composite nanofibers for hybridization detection of specific K-ras gene that is highly associated with colorectal cancer via multiple signal amplification strategy has been developed. The carboxylated multiwalled carbon nanotubes (MWCNTs) doped nylon 6 (PA6) composite nanofibers (MWCNTs-PA6) was prepared using electrospinning, which served as the nanosized backbone for thionine (TH) electropolymerization. The functional composite nanofibers [MWCNTs-PA6-PTH, where PTH is poly(thionine)] used as supporting scaffolds for single-stranded DNA1 (ssDNA1) immobilization can dramatically increase the amount of DNA attachment and the hybridization sensitivity. Through the hybridization reaction, a sandwich format of ssDNA1/K-ras gene/gold nanoparticle-labeled ssDNA2 (AuNPs-ssDNA2) was fabricated, and the AuNPs offered excellent electrochemical signal transduction. The signal amplification was further implemented by forming network-like thiocyanuric acid/gold nanoparticles (TA/AuNPs). A significant sensitivity enhancement was obtained; the detection limit was down to 30fM, and the discriminations were up to 54.3 and 51.9% between the K-ras gene and the one-base mismatched sequences including G/C and A/T mismatched bases, respectively. The amenability of this method to the analyses of K-ras gene from the SW480 colorectal cancer cell lysates was demonstrated. The results are basically consistent with those of the K-ras Kit (HRM: high-resolution melt). The method holds promise for the diagnosis and management of cancer.

Temporal dynamics of RAS mutations in circulating tumor DNA in metastatic colorectal cancer: clinical significance of mutation loss during treatment.

PURPOSE: In metastatic colorectal cancer (mCRC), RAS mutation loss may occur during the standard-of-care regimen. In this study, we aimed to investigate the temporal dynamics of the RAS gene and its clinical significance. METHODS: This was a retrospective, single-center study that included 82 patients with tissue RAS-mutant (RAS-MT) mCRC who underwent circulating tumor DNA (ctDNA) RAS monitoring between January, 2013-April, 2023. Patients were analyzed for the rate of change over time to acquired RAS mutation loss (aRAS-ML) and clinicopathological factors. The prognostic relevance of mutation loss was assessed. RESULTS: aRAS-ML was detected in 33 (40.2%) patients, 32 of whom had a mutation loss in the first ctDNA RAS assay. Patients with a RAS mutation detected in the first assay had a median time of 8 months until the second ctDNA RAS assay, with 4.5% cases newly converted to aRAS-ML; no new conversions were detected at the third assay. The aRAS-ML group exhibited more single-organ metastases in the target organ during ctDNA measurement (aRAS-ML: 84.8% vs. RAS-MT: 59.2%, p = 0.02). Of the 33 patients with aRAS-ML, seven (21.2%) received anti-epidermal growth factor receptor (EGFR) therapy, with a median progression-free survival of 8 months. Multivariate analysis revealed that persistent ctDNA RAS mutation was an independent prognostic factor for overall survival (hazard ratio: 2.7, 95% confidence interval: 1.1-6.3, p = 0.02). CONCLUSION: The rate of ctDNA mutation loss in patients with RAS-MT mCRC decreases over time. Therefore, using a ctDNA RAS assay early in treatment will assist in challenging the use of EGFR regimens.

Correlation Between DCAMKL-1 Protein Expression and K-ras Gene Mutation in Colorectal Cancer.

Aim: To investigate the correlation between doublecortin and CaM kinase-like-1 (DCAMKL-1) protein expression, K-ras gene mutation, and their impact on patient prognosis in colorectal cancer (CRC). Methods: Immunohistochemistry was used to detect the expression of DCAMKL-1 protein in 60 cases of colorectal adenoma, 82 cases of CRC (including 65 cases of lymph node metastasis) and paraffin-embedded paracancerous intestinal mucosal tissue. K-ras gene mutations in primary CRC lesions were detected using an amplification-refractory mutation system and fluorescent polymerase chain reaction. The relationship between DCAMKL-1 protein expression and K-ras gene mutations with the clinicopathological characteristics of patients with CRC was analyzed. Univariate Kaplan‒Meier survival analysis and multivariate Cox regression analysis were performed using follow-up data. Results: The mutation rate of the K-ras gene in 82 cases of CRC was 48.8% (40/82). The positivity rate for the presence of DCAMKL-1 protein in CRC was 70.7% (58/82), significantly higher than that for colorectal adenomas (53.3%; 32/60) and paracancerous intestinal mucosa (0%; 0/82) (P<0.05). The positive expression rate for the presence of DCAMKL-1 protein in 65 patients with lymph node metastasis was higher in the primary lesions (69.2%; 45/65) than in the lymph node metastases (52.3%; 34/65) (χ2=12.087, P=0.001). The K-ras gene mutation status was positively correlated with DCAMKL-1 protein expression (r=0.252, P=0.022). Conclusion: In this study, a potential positive correlation between K-ras gene mutation and DCAMKL-1 protein expression was identified in CRC tissues. The assessment of K-ras gene mutation status and DCAMKL-1 protein expression holds promise for augmenting early diagnosis and prognosis evaluation in CRC. This approach may improve the overall prognosis and survival outcomes for CRC patients.

RAS-Mutated Cytologically Indeterminate Thyroid Nodules: Prevalence of Malignancy and Behavior Under Active Surveillance.

Background: Genomic profiling is now available for risk stratification of cytologically indeterminate thyroid nodules (ITNs). Mutations in RAS genes (HRAS, NRAS, KRAS) are found in both benign and malignant thyroid nodules, although isolated RAS mutations are rarely associated with aggressive tumors. Because the long-term behavior of RAS-mutant ITNs is not well understood, most undergo immediate surgery. In this multicenter retrospective cohort study, we characterize tumor growth kinetics of RAS-mutant ITNs followed with active surveillance (AS) using serial ultrasound (US) scans and examine the histopathologic diagnoses of those surgically resected. Methods: US and histopathologic data were analyzed retrospectively from two cohorts: (1) RAS-mutant ITNs managed with AS at three institutions (2010-2023) and (2) RAS-mutant ITNs managed with immediate surgery at two institutions (2016-2020). AS cohort subjects had ≥3 months of follow-up and two or more US scans. Cumulative incidence of nodule growth was determined by the Kaplan-Meier method and growth by ≥72% change in tumor volume. Pathological diagnoses for the immediate surgery cohort were analyzed separately. Results: Sixty-two patients with 63 RAS-mutated ITNs under AS had a median diameter of 1.7 cm (interquartile range [IQR] 1.2-2.6) at time of diagnosis. During a median AS period of 23 months (IQR 9.5-53.5 months), growth was observed in 12 of 63 nodules (19.0%), with a cumulative incidence of 1.9% (1 year), 23.0% (3 years), and 28.0% (5 years). Most nodules (81.0%) demonstrated stability. Surgery was ultimately performed in 6 nodules, of which 1 (16.7%) was malignant. In the cohort of 209 RAS-mutant ITNs triaged to immediate surgery, 33% were malignant (23.9% American Thyroid Association [ATA] low-risk cancers, 7.2% ATA intermediate-risk, and 1.9% ATA high-risk. During a median follow-up of 6.9 (IQR 4.4-7.1) years, there were no disease-specific deaths in these patients. Conclusions: We describe the behavior of RAS-mutant ITNs under AS and find that most demonstrate stability over time. Of the resected RAS-mutant nodules, most were benign; of the cancers, most were ATA low-risk. Immediate surgical resection of all RAS-mutant ITNs appears to be a low-value practice. Further research is needed to help define cases most appropriate for AS or immediate surgery.

Analysis of H-ras Mutations and Immunohistochemistry in Recurrence Cases of High-Grade Oral Squamous Cell Carcinoma.

BACKGROUND: This study is focused on the identification of gene mutations in H-ras which are probably associated with tumor recurrence in oral squamous cell carcinoma (OSCC) following conventional therapy. METHODS: Surgically removed biopsies from OSCC patients without recurrence (n = 43) and biopsies from recurrent cases (n = 19) were analyzed. Also, gingival tissues (n = 5) from normal individuals were processed and considered as control. DNA was extracted and amplified using primers for exons 1 and 2 for the H-ras gene, and then DNA products were analyzed using Sanger's sequencing technique. Besides, H-ras expression was compared in samples by immunostaining (IHC), using anti-ras antibody. RESULTS: Demographic data show that smoking habit in patients and recurrent tumors was ~ 44.1 and 78%, respectively. The major site of malignancy was tongue tissue (40-60%). The rate of pathological stage III/IV were 41.8 and 100% in primary tumors and recurrence malignancy respectively. The sequencing data showed that a specific mutation in H-ras gene, Gly12Ala (G6266A) in recurrence samples and primary cases was detected in ~ 66.6% and 10% respectively. Accumulation of H-ras protein in tissues was relatively high scores (> 5) in both primary and recurrence tumors. The H-ras mutation detected was associated with increased level of H-ras protein accumulated in the malignant cells (IHC data). CONCLUSION: These data may suggest that regardless of the causes and factors involved, Gly12Ala (G6266A) is associated with recurrence in high-grade OSCC tumors.

A fluorescence-electrochemiluminescence dual-mode sensor based on a "switch" system for highly selective and sensitive K-ras gene detection.

Herein, an fluorescence (FL)-electrochemiluminescence (ECL) dual-mode biosensor is constructed based on the dual-signal "turn-on" strategy of functionalized metal-organic frameworks nanosheets (RuMOFNSs)-tetraferrocene for K-ras gene detection, and the mechanism of bursting through front-line orbital theory is explained for the first time. Amino-functionalized tetraferrocene-labeled probe DNA molecules are linked to RuMOFNSs by covalent amide bonds, acting as FL and ECL intensity switches. The target DNA, complementary to the probe DNA, triggers cyclic amplification of the target by nucleic acid exonuclease III (Exo III), repelling tetraferrocene reporter groups away from RuMOFNSs and inhibiting the electron transfer process and photoinduced electron transfer (PET) effect. These phenomena induce a double turn-on of FL and ECL signals with a high signal-to-noise ratio. The developed FL-ECL dual-mode sensing platform provides sensitive detection of the K-ras gene with detection limits of 0.01 fM (the detection range is 1 fM to 1 nM) and 0.003 fM (the detection range is 0.01 fM to 10 pM), respectively. In addition, the proposed dual-mode sensor can be easily extended to detect other disease-related biomarkers by changing the specific target and probe base sequences, depicting potential applications in bioanalysis and early disease diagnosis.

Analysis of RAS gene mutations in adverse events during first induction chemotherapy in childhood acute lymphoblastic leukemia.

Background: The rat sarcoma virus (RAS) pathway controls cell proliferation, differentiation, and apoptosis, which have been implicated in the pathogenesis of various hematological malignancies. Prognostic importance of RAS gene mutation, relatively frequently in childhood acute lymphoblastic leukemia (ALL), has been debated. We aimed to study RAS gene mutation profile and prognosis in 93 children with newly diagnosed ALL. Methods: We retrospectively analyzed clinical characteristics, treatment, and outcomes of 93 ALL children during first induction chemotherapy in Anhui Provincial Children's Hospital under the Chinese Children's Leukemia Group-acute lymphoblastic leukemia 2018 (CCLG-ALL-2018). All genomic DNA samples were obtained from bone marrow mononuclear cells upon new diagnosis. RAS gene mutation was performed by polymerase chain reaction (PCR). All children were stratified into standard-, medium-, and high-risk groups, and then treated with risk-based regimens according to CCLG-ALL-2018 protocol. Results: Of 93 ALL children, 26 (27.9%) were positive for RAS mutation, among whom 19 had N-RAS mutation, 8 had K-RAS mutation, and 1 had a double mutation. The ETV6/RUNX1 fusion gene was the most common genetic alteration (n=16, 17.2%). The most common adverse events during first induction chemotherapy were coagulation abnormalities (n=76, 81.7%), followed by fever (n=71, 76.3%) and alanine transaminase (ALT) elevation (n=34, 36.6%). Compared with negative RAS mutation group, the risk of hyperbilirubinemia was significantly reduced in RAS mutation group (P=0.018), and there was no significant difference in any other adverse events. The average duration of agranulocytosis during first induction chemotherapy was 6 days, and the average duration of agranulocytosis in RAS mutation group and RAS negative group was 6 and 5 days, with no significant difference. Multivariate linear regression analysis showed that in RAS mutation group, when body mass index (BMI) exceeded the median value of this ALL population (BMI >15.38), the risk of agranulocytosis was significantly increased (P=0.003). Conclusions: Newly diagnosed ALL in children with RAS mutation is less likely to be associated with fusion gene expression. RAS mutation increases the risk of agranulocytosis duration during first induction chemotherapy, lowers BMI and reduces the risk of hyperbilirubinemia in ALL children.

Somatic mutation detection and KRAS amplification in testicular germ cell tumors.

Background: Testicular Germ Cell Tumors (TGCT) are the most common cancer among young adult men. The TGCT histopathology is diverse, and the frequency of genomic alterations, along with their prognostic role, remains largely unexplored. Herein, we evaluate the mutation profile of a 15-driver gene panel and copy number variation of KRAS in a large series of TGCT from a single reference cancer center. Materials and methods: A cohort of 97 patients with TGCT, diagnosed at the Barretos Cancer Hospital, was evaluated. Real-time PCR was used to assess copy number variation (CNV) of the KRAS gene in 51 cases, and the mutation analysis was performed using the TruSight Tumor 15 (Illumina) panel (TST15) in 65 patients. Univariate analysis was used to compare sample categories in relation to mutational frequencies. Survival analysis was conducted by the Kaplan-Meier method and log-rank test. Results: KRAS copy number gain was a very frequent event (80.4%) in TGCT and presented a worse prognosis compared with the group with no KRAS copy gain (10y-OS, 90% vs. 81.5%, p = 0.048). Among the 65 TGCT cases, different variants were identified in 11 of 15 genes of the panel, and the TP53 gene was the most recurrently mutated driver gene (27.7%). Variants were also detected in genes such as KIT, KRAS, PDGFRA, EGFR, BRAF, RET, NRAS, PIK3CA, MET, and ERBB2, with some of them potentially targetable. Conclusion: Although larger studies incorporating collaborative networks may shed the light on the molecular landscape of TGCT, our findings unveal the potential of actionable variants in clinical management for applying targeted therapies.

Loss of Heterozygosity in the Circulating Tumor DNA and CD138+ Bone Marrow Cells in Multiple Myeloma.

Multiple myeloma (MM) is characterized by heterogeneity of tumor cells. The study of tumor cells from blood, bone marrow, plasmacytoma, etc., allows us to identify similarities and differences in tumor lesions of various anatomical localizations. The aim of this study was to compare the loss of heterozygosity (LOH) by tumor cells by assessing STR profiles of different MM lesions. We examined paired samples of plasma circulating tumor DNA (ctDNA) and CD138+ bone marrow cells in MM patients. For patients with plasmacytomas (66% of 38 patients included), the STR profile of plasmacytomas was also studied when biopsy samples were available. Diverse patterns of LOH were found in lesions of different localization for most patients. LOH in plasma ctDNA, bone marrow, and plasmacytoma samples was found for 55%, 71%, and 100% of patients, respectively. One could expect a greater variety of STR profiles in aberrant loci for patients with plasmacytomas. This hypothesis was not confirmed-no difference in the frequency of LOH in MM patients with or without plasmacytomas was found. This indicates the genetic diversity of tumor clones in MM, regardless of the presence of extramedullar lesions. Therefore, we conclude that risk stratification based on molecular tests performed solely on bone marrow samples may not be sufficient for all MM patients, including those without plasmacytomas. Due to genetic heterogeneity of MM tumor cells from various lesions, the high diagnostic value of liquid biopsy approaches becomes obvious.

[Clinical Significance of RAS Gene Mutations in Patients with Acute Myeloid Leukemia].

OBJECTIVE: To investigate the clinical characteristics of RAS gene mutations in patients with acute myeloid leukemia (AML). METHODS: 43 myeloid gene mutations were detected using next-generation sequencing (NGS) in 180 patients with AML who were first diagnosed between May 2011 and February 2021. The molecular and clinical features of RAS gene mutations and their effects on efficacy and survival of patients were retrospectively analyzed. RESULTS: Among 180 AML patients, the proportion of mutations in RAS pathway-related genes were NRAS (14.4%), KRAS (2.2%), FLT3-ITD (13.8%), PTPN11 (7.7%), KIT (5.0%), FLT3-TKD (3.8%) and CBL (2.7%). Seventy-three (40.6%) AML patients had gene mutations associated with the RAS pathway.The number of peripheral blood white blood cells and the proportion of bone marrow primitive juvenile cells in patients with NRAS/KRAS gene mutation were higher than those of patient with RAS wild-type, the difference was statistically significant (P<0.05). NRAS/KRAS gene mutations were significantly associated with the CBL gene mutation(r=0.287). In young AML patients (age <60 years), there were no significant differences in complete response rate (CR), progression-free survival (PFS), and overall survival (OS) between patients with RAS gene mutation and those with wild-type(P>0.05). In elderly AML patients (age≥60 years), PFS and OS in RAS mutants were significantly lower than those in wild-type patients(P<0.05). CONCLUSION: In AML patients, RAS gene mutation is relatively common, and RAS gene mutation is associated with clinical characteristics and efficacy of patients, and may be a molecular marker of poor prognosis for elderly AML.

Neurofibroma Within a Nevus Sebaceus: A Case Report.

Nevus sebaceus most commonly presents as a yellow, alopecic plaque on the head or neck in childhood and evolves into a verrucous plaque at puberty. Numerous secondary tumors may arise within nevus sebaceus lesions. Tumors of mesenchymal origin have been rarely documented. We present a unique case of a patient who presented with a nevus sebaceus on the scalp. Excision of the tumor and subsequent histopathology of the lesion revealed a nevus sebaceus with a desmoplastic trichilemmoma, a tumor of follicular infundibulum, and a neurofibroma. This case highlights a rare finding of a mesenchymal tumor, and the first reported neurofibroma, arising in association with a nevus sebaceus.

The frequency and clinicopathological significance of NRAS mutations in primary cutaneous nodular melanoma in Indonesia.

BACKGROUND: Melanoma is a lethal skin malignancy with a high risk of metastasis, which prompts a need for research on treatment targets and prognostic factors. Recent studies show that the presence of neuroblastoma RAS viral oncogene homolog (NRAS) mutation can influence cell growth in melanomas. The NRAS mutation, which stimulates the mitogen-activated protein kinase (MAPK) signaling pathway, is associated with a lower survival rate. However, evidence from Indonesia population is still very rare. Further understanding of the role of NRAS mutations in Indonesian melanoma cases will be crucial in developing new management strategies for melanoma patients with NRAS mutations. AIMS: To explore the frequency of NRAS mutations and their clinicopathological associations in patients with primary nodular cutaneous melanoma in Central Java and Yogyakarta, Indonesia. METHODS AND RESULTS: Fifty-one paraffin-embedded tissue samples were collected from primary nodular skin melanoma cases between 2011 and 2019 from the two largest referral hospitals in Yogyakarta and Central Java, Indonesia. The NRAS mutation status was evaluated using qualitative real-time polymerase chain reaction (qRT-PCR). The association of NRAS mutation was analyzed with the following: age, gender, location, lymph node metastasis, ulceration, mitotic index, tumor-infiltrating lymphocytes (TILs), necrosis, tumor thickness, lymphovascular invasion (LVI), and tumor size. NRAS mutations were detected in 10 (19.6%) samples and predominantly observed (60%) in exon 2 (G12). These mutations were significantly correlated with lymph node metastases (p = .000); however, they were not associated with other variables analyzed in this study. CONCLUSIONS: The prevalence of NRAS mutations in primary nodular cutaneous melanoma cases from Indonesia is consistent with previous studies and is significantly associated with increased lymph node metastases. However, the predominant mutation detected in exon 2 (G12) is different from previous studies conducted in other countries. This suggests that melanoma cases in Javanese people have different characteristics from other ethnicities.

Therapeutic impact of determination of RAS mutations in the plasma of patient with colorectal cancer.

Stage IV colorectal cancer treatment includes targeted therapy depending on RAS status. During disease progression, loss or gain of RAS mutations could happen, supporting the hypothesis of the evolutionary pressure of therapy. Circulating tumor DNA (ctDNA) are nucleic acids released to the bloodstream by the tumor during its development and may be detected by liquid biopsy. The Idylla© Biocartis, a fully automated real-time-PCR-based molecular diagnostic system, was used in a patient with metastatic colorectal cancer with a NRAS mutation in progression after several therapeutic lines. The ctDNA mutational analysis was performed and revealed the absence of mutations in the KRAS, NRAS, and BRAF genes. The patient started the third line of palliative chemotherapy with irinotecan + cetuximab and achieved a partial response for the first time. The authors describe a case in which liquid biopsy determined the higher progression-free survival achieved.

Clinical retrospective study on the expression of the PD-L1 molecule in sporadic colorectal cancer and its correlation with K-ras gene mutations in Chinese patients.

OBJECTIVE: To detect the expression of PD-L1 and K-ras gene status in colorectal cancer tissues and analyze the relationship between PD-L1 expression and the clinicopathological features and K-ras gene status in colorectal cancer. METHODS: Two hundred fifty colorectal cancer tissues were collected from the First Affiliated Hospital of Nanchang University. The normal intestinal mucosal tissues of 20 patients were randomly selected for inclusion in the control group. PD-L1 expression was detected by immunohistochemistry. K-ras gene mutation in colorectal cancer tissues was detected by sequencing. The clinical significance of PD-L1 expression and relationship between PD-L1 expression and K-ras gene mutation were analyzed. RESULTS: The immunohistochemistry assay showed that PD-L1 was highly expressed in colorectal cancer. The positive expression of PD-L1 was increased with lymph node metastasis and high TNM stage. The 5-year survival rate of PD-L1-positive patients was significantly lower than that of PD-L1-negative patients. The K-ras gene mutation rate was 35.6%, and the main mutation site was in codon 12. The positive PD-L1 expression rate in patients with K-ras gene mutations was significantly higher than that in patients with wild-type K-ras gene mutations. CONCLUSION: PD-L1 is highly expressed in colorectal cancer, and its expression is related to metastasis and tumor stage. PD-L1 expression is closely related to K-ras gene mutation, and the K-ras gene status may affect PD-L1 expression. TRIAL REGISTRATION: retrospectively registered.