Strategies to target energy metabolism in consensus molecular subtype 3 along with Kirsten rat sarcoma viral oncogene homolog mutations for colorectal cancer therapy.

Alterations in cellular energy metabolism play a critical role in colorectal cancer (CRC), which has been identified as the definition of consensus molecular subtypes (CMSs), and CMS3 tumors exhibit energy metabolism signatures along with Kirsten rat sarcoma viral oncogene homolog (KRAS)-activating mutations. This review summarizes the relationship between CMS3 tumors associated with mutated KRAS and energy metabolism in CRC, especially for the dysregulated energy metabolism that affects tumor cell proliferation, invasion, and migration. Furthermore, this review concentrates on the role of metabolic genes and factors and signaling pathways, which coupled with a primary energy source connected with the CMS3 associated with mutated KRAS, induce metabolic alterations. The strategies to target energy metabolism for the metabolic alterations in mutated KRAS CRC are also introduced. In conclusion, dysregulated energy metabolism has a close relationship with mutated KRAS in CMS3 tumors. Therefore, selective inhibitors or agents against metabolic targets or KRAS signaling may be clinically useful for CMS3 tumor treatment through a personalized approach for patients with cancer.

Synchronous endometrioid adenocarcinomas in the uterine cervix and corpus.

It is frequently difficult to distinguish multiple primary carcinomas from single primary carcinoma with metastasis. Here, we report a case of synchronous endometrioid adenocarcinomas that independently occurred in the uterine cervix and corpus. A 47-year-old woman complaining of genital bleeding was preoperatively diagnosed with cervical adenocarcinoma with an endometrial lesion. On surgical treatment, two separate malignant lesions bearing endometrioid adenocarcinoma were identified in the uterine cervix and cavity. Although both lesions expressed the same type of human papillomavirus (HPV) gene, type 16, microscopic continuity was not observed. Furthermore, we detected a critical difference in PTEN mutation between the tumors and finally diagnosed this case as multiple primary cancers. This is the first report to show multiple primary endometrioid adenocarcinomas simultaneously arising in the uterine cervix and corpus. Considering the rarity of this case, the coexistence of HPV suggests its possible involvement in the carcinogenesis of the endometrioid adenocarcinomas.

Clinicopathological and genetic differences between low-grade and high-grade colorectal mucinous adenocarcinomas.

BACKGROUND: Although colorectal mucinous adenocarcinomas (MCs) are conventionally regarded as exhibiting high-grade differentiation, they can be divided by differentiation into 2 groups according to the glandular appearance: low-grade mucinous adenocarcinoma (low-MC) and high-grade mucinous adenocarcinoma (high-MC). METHODS: Patients with colorectal cancer (CRC) who underwent surgical resection between 2000 and 2012 were enrolled in this study. Among the cases with MC, the clinicopathological and genetic differences between low-MC and high-MC were investigated with next-generation sequencing. RESULTS: A total of 1373 patients with CRC were analyzed. Forty patients (2.9%) had MC, and 13 patients had high-MC. Patients with MC had significantly shorter disease-free survival (DFS) and overall survival (OS) periods than those with nonmucinous carcinoma. When low-MC patients and high-MC patients were compared, those with high-MC had significantly shorter DFS and OS periods than those with low-MC. Multivariate analyses revealed that high-MC was significantly associated with both shorter DFS and shorter OS, but low-MC was not. A genome analysis revealed that low-MC had a considerably larger number of mutations than high-MC, and Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations and adenomatous polyposis coli mutations were particularly frequently found in low-MC. In contrast, SMAD family member 4 (SMAD4) mutations were frequently found in high-MC. CONCLUSIONS: High-MC is an independent prognostic factor in CRC (but low-MC is not), and it is genetically different from other CRCs, including low-MC. Both the clinicopathological differences and the genetic differences suggest that low-MC and high-MC should be distinguished in clinical settings.

Advances in Systemic Therapy in Pancreatic Cancer.

Substantial progress has been made toward understanding biology and developing new therapies for pancreatic ductal adenocarcinoma (PDAC). In this review, new insights from genomic profiling, as well as implications for treatment and prognosis, are discussed. New standards of care approaches with a focus on drug therapies are discussed for the treatment of resectable and advanced PDAC. The role of targeted and immune therapies remains limited; cohorts likely to benefit from these approaches are discussed. Promising, preliminary results regarding experimental therapies are reviewed.

Clinical outcomes of KRAS-mutant non-small cell lung cancer under untargeted therapeutic regimes in the real world: a retrospective observational study.

Background: Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation seemingly suffered less effective therapeutic regimens in the absence of widely-accepted targeted drugs compared with other mutation types in non-small cell lung cancer (NSCLC). However, whether these non-selective therapy schedules for KRAS mutation matters is still under debate. Correspondingly, we aimed to compare the long term expectancy of indicated therapeutic regimes and further explore the optimal schemes of KRAS mutated NSCLC in the absence of targeted drugs in this retrospective study cohort. Methods: We conducted a single-center retrospective analysis among 66 patients diagnosed with KRAS-mutant advanced NSCLC from November 2018 to December 2020. These enrolled cases were divided into different subgroups in light of mutant isotypes, pathological characteristics, and therapeutic regimes to uncover indicated long-term survival benefits. Additionally, clinical outcomes of treatment schedules and interventional lines to KRAS-mutant NSCLC were described in detail. Results: This cohort enrolled 8 patients with stage IIIB (12.1%) and 58 patients with stage IV (87.9%) with the median age 62 years, ranging from 32 to 91 years old. Genetically, G12C conducted as the most common KRAS mutation type, accounting for 30.3%. Pemetrexed combined with platinum chemotherapy seemed to be a priority (72.7%), and chemotherapy combined with immunotherapy became an alternative (15.2%) in clinic. Performing further analysis of long-term survival of patients receiving different treatment methods indicated that the median overall survival (mOS) in first-line therapy with antiangiogenesis or untreated was 13 and 12 months, respectively (P=0.79). In the first-line regimen, median survival was 17 months for patients who received combined immune checkpoint inhibitors and 12 months for those who did not (P=0.34). The mOS was 20 months for those who had used immune checkpoint inhibitors and 12 months for those who had not (P=0.11). Survival analysis results of NSCLC patients with different KRAS mutation types showed the median survival time of patients with G12C mutation type and patients without with nonG12C mutation type was 19 and 12 months, respectively (P=0.37). Conclusions: In the absence of KRAS targeted drugs, available treatment plans failed to benefit KRAS mutant sufferers regardless of isotypes, making the KRAS-targeted drugs urgent.

Comprehensive analysis of T cell receptor repertoire in patients with KRAS mutant non-small cell lung cancer.

Background: Kirsten rat sarcoma viral oncogene homolog (KRAS) is one of the most frequently mutated oncogenes in non-small cell lung cancer (NSCLC). The administration of immunotherapy has demonstrated significant efficacy in prolonging the overall survival of patients with KRAS mutation in recent years. However, the efficacy of immunotherapy in KRAS mutant NSCLC is variable. Analysis of T cell receptor (TCR) repertoire may contribute to a better understanding of the mechanisms behind such differential outcomes. Methods: A total of 47 patients with KRAS mutant NSCLC were enrolled in this study. Deep sequencing of the TCR ß chain complementarity-determining regions in tumor tissue and paired peripheral blood specimens was conducted. Comprehensive analysis of TCR repertoire metrics was performed with different KRAS mutation subtypes and concomitant mutations. Moreover, the associations between TCR repertoire metrics and tumor mutation burden (TMB), as well as programmed death-ligand 1 were explored, respectively. Results: TCR repertoire metrics, including Shannon index, Clonality, and Morisita index (MOI), showed no significant differences among different KRAS mutation subtypes. The similar results were observed between patients with tumor protein p53 (TP53) mutation and those with wild-type TP53. In contrast, although no significant differences were found in Shannon index and Clonality, patients with KRAS/serine/threonine kinase 11 (STK11) comutation showed a significantly higher MOI compared to their STK11 wild-type counterparts (P=0.012). In addition, TCR repertoire metrics were neither associated with TMB nor programmed death-ligand 1 expression in KRAS mutant NSCLC. Conclusions: This retrospective study comprehensively described the TCR repertoire in KRAS mutant NSCLC. A higher MOI represented more overlap of the TCR repertoire between tumor tissue and paired peripheral blood, indicating distinctive immunological features in NSCLC with KRAS/STK11 comutation.

Prognostic impact of high-risk factors and KRAS mutation in patients with stage II deficient mismatch repair colon cancer: a retrospective cohort study.

Background: Deficient mismatch repair (dMMR) is associated with a good prognosis in patients with stage II colon cancer and observation is recommended after surgery in these patients. In contrast, patients with high-risk factors and Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation is associated with a poor prognosis in colon cancer. However, the prognosis and treatment of patients with dMMR colon cancer combined with high-risk factors or KRAS mutation remains unclear. This study aimed to evaluate whether patients with dMMR colon cancer combined with high-risk factors or KRAS mutation require further treatment. Methods: This single-center retrospective study included patients who received radical surgical resection and mismatch repair (MMR) immunohistochemical detection at The Sixth Affiliated Hospital of Sun Yat-sen University between May 2011 and March 2021. The high-risk factors and KRAS mutation were assessed by clinicopathological data and targeted sequencing. Associations with disease-free survival (DFS) were evaluated using multivariable Cox models. Results: Among the 1,357 patients with stage II colorectal cancer included, 226 of these patients had dMMR. Patients in the dMMR group were more likely to be younger [<50 years: odds ratio (OR) =0.401, 95% CI: 0.288-0.558, P<0.001], with poor differentiation (OR =5.800, 95% CI: 3.437-9.787, P<0.001), no perineural invasion (OR =0.132, 95% CI: 0.047-0.368, P<0.001), and more than 12 excised lymph nodes (OR =0.427, 95% CI: 0.188-0.968, P=0.042). The disease-free survival (DFS) of patients with stage II dMMR colon cancer with high-risk factors was similar to that of patients without high-risk factors (hazard ratio (HR) =1.285, 95% CI: 0.273-6.051, P=0.607). A total of 836 patients had complete data regarding KRAS status. Compared with KRAS wild-type patients, patients with KRAS gene mutation had a trend of poor prognosis in patients with stage II colon cancer (HR=1.483, 95% CI: 0.983-2.239, P=0.061). In addition, dMMR appeared to be a protective factor in patients with KRAS mutation (HR =0.138, 95% CI: 0.019-1.002, P=0.0501). Conclusions: The survival of patients with stage II dMMR colon cancer with high-risk factors was similar to that of patients without high-risk factors, regardless of the presence of KRAS mutation.

KRAS Gene Copy Number as a Negative Predictive Biomarker for the Treatment of Metastatic Rectal Cancer With Cetuximab: A Case Report.

Background: Close to one third of colorectal cancer (CRC) patients are diagnosed with metastatic CRC (mCRC). Patients with wild-type RAS and BRAF usually receive anti-EGFR monoclonal antibody therapy containing cetuximab. Overall, 30-50% of mCRC patients are reported to harbor RAS mutations, and RAS mutation status should be assessed when considering EGFR inhibitor treatment according to mCRC biomarker guidelines. Of note, 0.67-2% of patients with CRC harbored a KRAS amplification. Here we reported a case of advanced rectal cancer with wild-type RAS and BRAF in a male patient who harbored a KRAS amplification during anti-EGFR treatment. Case Presentation: A 46-year-old man was diagnosed with rectal adenocarcinoma with liver metastases (cT3NxM1a, stage IVA). After receiving first-line irinotecan- fluorouracil chemotherapy (FOLFIRI) plus cetuximab, second-line capecitabine- oxaliplatin chemotherapy (XELOX) plus bevacizumab, and third-line regorafenib, he rechallenged FOLFIRI and cetuximab for seven cycles, achieving a prolonged survival of at least 5 months. The KRAS copy number of circulating tumor DNA (ctDNA) was assessed during treatment. Notably, apart from serum carbohydrate antigen 199 (CA199) and carcinoembryonic antigen (CEA), the change of plasm Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) copy number appeared to strongly correlate with treatment response. Conclusion: Our findings suggest that the dynamic change of KRAS copy number on ctDNA during treatment might be a negative predictive biomarker. Additionally, RAS and BRAF wild-type mCRC patients who are resistant to first-line FOLFIRI plus cetuximab therapy may respond well to the FOLFIRI plus cetuximab "rechallenged" strategy.

Analysis of RAS gene mutations in cytogenetically normal de novo acute myeloid leukemia patients reveals some novel alterations.

Rat sarcoma gene (RAS) holds great importance in pathogenesis of acute myeloid leukemia (AML). The activated mutations in Neuroblastoma rat sarcoma viral oncogene homolog (NRAS) and Kirsten rat sarcoma viral oncogene homolog (KRAS) confers proliferative and survival signals, deliberating numerous effects on overall survival and progression free survival in AML patients. In this study thirty one (31) blood samples of adult newly diagnosed AML patients were collected to identify possible incidence of mutations through amplification of KRAS (exon 1 and 2) and NRAS gene (exon 1 and 2) using polymerase chain reaction (PCR). Amplicons were then subjected to sequencing and were analyzed through Geneious Prime 2019. Five of thirty one (16.12%) patients had altered sites in either NRAS or KRAS. The NRAS mutations were observed in three AML patients (N = 3, 9.67%). A novel missense mutation NRAS-I36R (239 T > G) representing a substitution of single nucleotide basepair found in NRAS exon 1 while exon 2 was detected with heterozygous mutation NRAS-E63X (318G > T) and insertion (A), resulting in frameshift of the amino acid sequence and insertion of two nucleotide basepairs (TA) in two of the patients. KRAS mutations (N = 2, 6.45%) were found in exon 1 whereas no mutations in KRAS exon 2 were detected in our patient cohort. Mutation in KRAS Exon 1, KRAS-D30N (280G > A) was observed in two patients and one of them also had a novel heterozygous mutation KRAS-L16N (240G > C). In addition there was no statistically significant association of mutRAS gene of AML patients with several prognostic markers including age, gender, karyotyping, CD34 positivity, cytogenetic abnormalities, total leukocyte count, white blood cell count and French-American-British (FAB) classification. However, the presence of mutRAS gene were strongly associated (p = 0.001) with increased percentage of bone marrow blasts. The prevalence of mutations in correlation with clinical and hematological parameter is useful for risk stratification in AML patients.

Clinicoradiopathological features and prognosis according to genomic alterations in patients with resected lung adenocarcinoma.

BACKGROUND: We investigated the clinicoradiopathological features and prognosis according to genomic alterations in patients with surgically resected lung adenocarcinoma. METHODS: Patients who underwent surgical resection for pathologic stage I, II, or IIIA lung adenocarcinoma between 2009 and 2016 and for whom results regarding EGFR mutation, ALK immunohistochemistry (IHC), and KRAS mutation were available were included. Clinicoradiopathological characteristics, genomic alterations, and disease-free survival were analyzed retrospectively. RESULTS: Of 164 patients, 86 (52.4%) were female and 94 (57.3%) were never-smokers. The most common imaging patterns were part-solid lesion (67.7%) followed by solid (26.2%) and non-solid (6.1%) lesions. EGFR mutation, ALK IHC, and KRAS mutation were positive in 95 (57.9%), 9 (5.5%), and 11 (6.7%) patients, respectively. EGFR mutation positivity was associated with female sex, never-smoker, subsolid pattern on radiological examination, and acinar or papillary predominant histologic subtype. ALK IHC positivity was associated with longer maximal diameter, advanced stage, solid pattern on radiological examination, solid predominant histologic subtype, and distant metastasis during follow-up. KRAS mutation positivity was associated with male sex, smoker, solid pattern on radiological examination, and invasive mucinous adenocarcinoma on histologic analysis. In multivariable analysis, ALK IHC positivity and lymph node involvement were independently associated with recurrence. However, solidity was not an independent risk factor for recurrence. CONCLUSIONS: Genomic alterations are associated with clinicoradiopathologic features in patients with resected lung adenocarcinoma. Identifying genomic alterations could help to predict the prognosis of early-stage lung adenocarcinoma.

Modulating Pluripotency Network Genes with Omega-3 DHA is followed by Caspase- 3 Activation and Apoptosis in DNA Mismatch Repair-Deficient/KRAS-Mutant Colorectal Cancer Stem-Like Cells.

BACKGROUND: Targeting DNA mismatch repair-deficient/KRAS-mutant Colorectal Cancer Stem Cells (CRCSCs) with chemical compounds remains challenging. Modulating stemness factors Bmi-1, Sox-2, Oct-4 and Nanog in CRCSCs which are direct downstream targets of carcinogenesis pathways may lead to the reactivation of caspase-3 and apoptosis in these cells. Omega-3 DHA modulates different signaling pathways involved in carcinogenesis. However, little is known, whether in vitro concentrations of DHA equal to human plasma levels are able to modulate pluripotency genes expression, caspase-3 reactivation and apoptosis in DNA mismatch repair-deficient/KRAS-mutant CRC stem-like cells. METHODS: DNA mismatch repair-deficient/KRAS-mutant CRC stem-like cells (LS174T cells) were treated with DHA, after which, cell number and proliferation-rate, Bmi-1, Sox-2, Nanog and Oct-4 expression, caspase-3 activation and apoptosis were evaluated with different cellular and molecular techniques. RESULTS: DHA changed the morphology of cells to apoptotic forms and disrupted cell connections. After 48h treatment with 50- to 200µM DHA, cell numbers and proliferation-rates were measured to be 86%-35% and 93.6%-45.7% respectively. Treatment with 200 µM DHA dramatically decreased the expression of Bmi-1, Sox- 2, Oct-4 and Nanog by 69%, 70%, 97.5% and 53% respectively. Concurrently, DHA induced caspase-3 activation by 1.8-4.7-fold increases compared to untreated cells. An increase in the number of apoptotic cells ranging from 9.3%-38.4% was also observed with increasing DHA concentrations. CONCLUSIONS: DHA decreases the high expression level of pluripotency network genes suggesting Bmi-1, Sox-2, Oct-4 and Nanog as promising molecular targets of DHA. DHA reactivates caspase-3 and apoptosis in DNA mismatch repair-deficient/KRAS-mutant CRC stem-like cells, representing the high potential of this safe compound for therapeutic application in CRC.

KRAS mutations testing in non-small cell lung cancer: the role of Liquid biopsy in the basal setting.

In advanced stage non-small cell lung cancer (NSCLC) patients, Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) testing may soon acquire a predictive significance to select patients for AMG510 treatment. Since tissue samples are not always available, liquid biopsy may represent a viable option for KRAS testing. Here, we review the last three years clinical practice performed on 194 plasma based liquid biopsies by next generation sequencing (NGS) SiRe® panel. In particular, 36 (18.6%) KRAS mutated cases were identified, with an overall median allelic frequency of 5.0% (ranging between 0.2% and 46.8%). No concomitant mutations were observed in the other NSCLC clinical relevant genes included in the SiRe® panel, such as epidermal growth factor receptor (EGFR) and v-Raf murine sarcoma viral oncogene homolog B (BRAF). Exon 2 p.G12C was the most common detected mutation (13/36, 36.1%). In conclusion, our data update and confirm that SiRe® NGS panel represents a robust analytical tool to assess KRAS mutational status on circulating tumor DNA. Further investigation is required to design more cost-effective diagnostic algorithms to harmonize clinical relevant biomarker testing on tissue and blood in advanced stage NSCLC clinical practice.

The response of PIK3CA/KRAS-mutant colorectal cancer stem-like cells to RGD-peptide FraC produced by the strawberry anemone: A promising water-soluble peptide-based inhibitor of metastasis-driver gene CXCR4, stem cell regulatory genes and self-renewal.

Colorectal cancer (CRC) is a stem cell-based disease. PIK3CA/KRAS-mutant CRC stem cells (CRCSCs) display high self-renewal, metastatic properties, high activity of PI3K and KRAS signaling pathways with chemoresistant phenotypes. Recently, RGD peptide (containing Arg-Gly-Asp motif)-based therapy of solid tumor cells has attracted much attention. However, little is known whether this method can target self-renewal capacity, key effectors of PI3K and KRAS signaling pathways such as metastasis-driver gene CXCR4 and stem cell regulatory genes with caspase-3 reactivation in CRCSCs overexpressing RGD-dependent integrins. The sea anemone Actinia fragacea produces a water-soluble RGD-peptide fragacea toxin C (FraC) suggesting the possible activity of FraC against PIK3CA/KRAS-mutant CRCSCs. Recombinant FraC was expressed via pET-28a(+)-FraC in E. coli and purified through affinity chromatography followed by performing SDS-PAGE and hemolytic activity assay. Next, PIK3CA/KRAS-mutant HCT-116 cells that serve as an attractive model for CRCSCs were treated with FraC. Thereafter, cell numbers, viability, proliferation, LDH activity, cytotoxicity index, CXCR4 and pluripotency network genes expression, self-renewal capacity, caspase-3 activity with apoptosis were evaluated. Caspase-1, -2, -3,…, -9 sequences were analyzed for RGD-binding motifs. FraC sequence and structure were also evaluated by bioinformatics software. FraC altered cellular morphology to round shapes and disrupted cell connections. 48 h post-treatment with 0.056- to 7.2 µM FraC resulted in 12 %-99 % and 8 %-97.6 % decreases in cell numbers and viabilities respectively and increased LDH activity by 0.2 %-66.7 % in a dose-dependent manner. The results of the cytotoxicity index showed that FraC induces significant toxicity on HCT-116 cells compared to PBMCs and Huvec cells. FraC dramatically decreased the expression of CXCR4 and pluripotency network genes Bmi-1, Sox-2, Oct-4 and Nanog followed by remarkable decreases in self-renewal capacity ranged from 91- to 0 colonies per well for 0.056- to 3.6 µM FraC after 2 weeks. Caspase-3 was found to contain an RGD-binding motif and its activity increased with increasing FraC concentrations followed by apoptosis induction. Potential RGD-binding motifs for FraC were also found in caspase-1, -7, -8 and -9. Unique advantages of FraC peptide, such as low molecular weight, water solubility, high sensitivity of CRC stem-like cells with more selective toxicity to this compound, targeting tumor cell membrane and self-renewal capacity along with the modulation of CXCR4 and stem cell regulatory genes as upstream and downstream effectors of undruggable PI3K and KRAS signaling pathways may open up avenues for FraC peptide-based therapy of PIK3CA/KRAS-mutant CRCSCs with lower toxicity on healthy cells.

RAS mutation: site of disease and recurrence pattern in colorectal cancer.

Somatic mutation status in metastatic colorectal cancer (CRC), and namely mutational activation of the Kirsten rat sarcoma viral oncogene homolog (KRAS) oncogene, is becoming more and more relevant in clinical practice. In this review, we describe the current data about the importance of associations between the mutational activation status of the KRAS oncogene and clinical outcomes, prognosis and metastatic patterns of CRC. The presence of a KRAS mutation is detected in approximately 30-50% of CRC and represents a powerful predictor of oncologic outcomes. It is associated with low response to systemic chemotherapy and for insensitivity to the anti-EGFR antibodies in the preoperative setting. It is more frequently associated with right colon cancer. In non-metastatic patients, KRAS mutation leads to more aggressive disease with shorter recurrence free survival (RFS) and more lung recurrences. After resection of CRC liver metastases (LiM), KRAS mutation is directly associated with increased risk of recurrence, worse overall survival (OS), and a distinct metastatic pattern with more invasive intrahepatic recurrence and increased recurrence outside of the liver, particularly in the lung, the peritoneum, and even in uncommon metastatic sites such as the brain and bones. As metastasectomy with curative intent is increasingly considered, a comprehensive approach of tumor biology is required to face the specific challenge of patients with metastatic CRCs. Thus, as it represents one of the strongest predictors of oncologic outcomes, integrating the KRAS mutational status at all the different stages of patient care appears crucial in order to adapt both medical and surgical strategies.

Highly sensitive and selective detection of single-nucleotide polymorphisms using gold nanoparticle MutS enzymes and a micro cantilever resonator.

Mutant DNAs are important markers useful for the diagnosis of human disease. Single-nucleotide polymorphisms (SNPs) represent the most common types of DNA mutations. As there is only a one base pair change in a single nucleotide between the SNP and the wild-type DNA, it is difficult to distinguish the SNPs. In this report, a highly sensitive and selective detection and discrimination of SNPs is performed using MutS, gold nanoparticles (AuNP) and a resonator. A single mismatched base exists between the SNP mutation and the probe DNA on the resonator, and MutS binds to the DNA at the location of the mismatch. As MutS is attached to AuNP (MutS-AuNP), both MutS and AuNP are adsorbed onto the resonator. The detection is based on the resonance frequency shift of the resonator following the adsorption of MutS-AuNP on the resonator. Highly sensitive detection of DNA mutations was achieved using AuNPs that act as mass amplifiers, and the obtained limit of detected was 100 fM. Additionally, our proposed method detected mutations in the presence of as little as 0.1% wild-type, and discrimination of specific mutations was also achieved. The results obtained from our proposed method suggest its potential for diagnosing cancer patients.

Genotyping and cytomorphological subtyping of lung adenocarcinoma based on liquid-based cytology.

BACKGROUND: Liquid-based cytology (LBC) samples allow immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and molecular testing of nucleic acids to be performed in the remaining fixed cells. The current study aimed to examine the relationship between gene mutational status and cytomorphological features in primary lung adenocarcinoma (ADC) using LBC materials. METHODS: Forty consecutive patients with primary lung ADC underwent surgical resection in our hospital. Cytological material was obtained by scraping the cut-surface of the lesion, and samples were fixed and stored as LBC materials using CytoRich Red. Epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations, anaplastic lymphoma kinase (ALK), and c-ros oncogene 1 (ROS1) gene rearrangements were detected, and cytomorphological studies were performed. RESULTS: Twenty cases (50%) were positive for EGFR mutation and four (10%) were positive for KRAS mutation. ALK gene rearrangement was identified in one case (2.5%) by IHC and FISH, and ROS1 gene rearrangement was identified in one case (2.5%) by IHC and real-time polymerase chain reaction. The KRAS-positive group included higher proportions of cases with an inflammatory background (100%), predominantly papillary architecture (75%), and papillary-type ADC pattern (75%) compared with the EGFR-positive group and the other group, which included ALK and ROS1 gene rearrangements. CONCLUSIONS: LBC material is suitable for use in molecular testing. Differences in major gene aberrations detected by this method might predict specific cytomorphological features.

Invasive mucinous adenocarcinoma of the lung.

Invasive mucinous adenocarcinoma (IMA) is a unique histological subtype of adenocarcinoma. Due to its low incidence rates, survival data for IMA is scarce and often contradictory. The clinical manifestations of IMA are not precise as compared to other adenocarcinomas, with some patients having bronchial mucus overflow. Difference in immunohistochemical expression levels is present in IMA and invasive non-mucinous adenocarcinomas (INMA). Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations are more frequent in IMAs, while epidermal growth factor receptor (EGFR) mutations are relatively rare. This makes it distinct from the other more common adenocarcinomas. Neuregulin 1 (NRG1) gene fusions are considered important therapeutic targets for IMA, suggesting that Afatinib may be an effective drug to treat IMA. However, IMA prognosis remains controversial.

Programmed cell death ligand 1 expression in cytologic and surgical non-small cell lung carcinoma specimens from a single institution: Association with clinicopathologic features and molecular alterations.

BACKGROUND: Programmed cell death ligand 1 (PD-L1) expression by the 22C3 pharmDx companion assay has been validated in surgical specimens to support pembrolizumab treatment decisions for patients with non-small cell lung carcinoma (NSCLC). The aims of this study were 1) to assess the adequacy of cytologic specimens for PD-L1 evaluation and 2) to explore correlations of PD-L1 expression with clinicopathologic and molecular features. METHODS: The study cohort included 100 cytology specimens (fluid [n = 28] and fine-needle aspiration [n = 72]) and 165 surgical specimens (biopsy [n = 138] and resection [n = 27]). The PD-L1 immunohistochemistry 22C3 assay and staining assessment were performed according to the manufacturer's instructions. PD-L1 expression was correlated with patients' demographics, pathologic characteristics, and molecular alterations. RESULTS: One hundred forty-two specimens (53.6%) were positive for PD-L1 expression (≥1%). No statistically significant difference in PD-L1 expression was identified between cytologic (56.0%) and surgical specimens (52.1%). Seventy-four of 190 tested cases (38.9%) had genetic alterations. PD-L1 positivity was significantly more prevalent in cases with genetic alterations than in cases without genetic alterations. Furthermore, both PD-L1 positivity and high PD-L1 expression (≥50%) had statistically significant associations with Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. PD-L1 expression had no significant association with histologic phenotypes or other clinicopathologic features. CONCLUSIONS: The data indicate that cytologic specimens are comparable to surgical specimens for PD-L1 evaluation. The association of PD-L1 expression with KRAS mutations may have clinical relevance in selecting patients with NSCLC for immunotherapy.

Molecular analysis of peripheral lung adenocarcinoma in brush cytology obtained by EBUS plus fluoroscopy-guided bronchoscopy.

BACKGROUND: More than 60% of patients with lung cancer are diagnosed at advanced stages. The introduction of targeted therapies requires molecular diagnosis to guide treatment. The aim of this study was to evaluate the feasibility of performing mutational analysis with brushing specimens obtained by radial-miniprobe endobronchial ultrasound (R-EBUS) plus fluoroscopy-guided bronchoscopy in patients with peripheral pulmonary adenocarcinoma. METHODS: Brushing specimens were deposited on cytological slides and were conserved in Roswell Park Memorial Institute (RPMI) culture medium. DNA was isolated to perform a mutational analysis with real-time quantitative polymerase chain reaction and Sanger sequencing for epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene homolog (KRAS). RESULTS: Thirty patients with adenocarcinoma were prospectively included. In 100% of the patients, the molecular study was viable with brushing specimens. In 16 (53.3%), KRAS or EGFR mutations were detected: 10 KRAS mutations (33.3%) and 6 EGFR mutations (20%). In a comparison with histological samples, a correlation of 86.6% was detected, and only 2 patients with wild-type results from brushing specimens presented with an EGFR mutation in histological samples. CONCLUSIONS: Brushing specimens conserved in RPMI medium and obtained by R-EBUS plus fluoroscopy-guided bronchoscopy are valid for molecular studies. They allow the detection of EGFR/KRAS mutations in patients with peripheral adenocarcinoma. In addition, invasive techniques are avoided, the risk of complications is reduced, and the obtained samples are optimized.

Role of Immunotherapy for Oncogene-Driven Non-Small Cell Lung Cancer.

The clinical application of immune checkpoint inhibitors (ICIs) has led to dramatic changes in the treatment strategy for patients with advanced non-small cell lung cancer (NSCLC). Despite the observation of improved overall survival in NSCLC patients treated with ICIs, their efficacy varies greatly among different immune and molecular profiles in tumors. Particularly, the clinical significance of ICIs for oncogene-driven NSCLC has been controversial. In this review, we provide recent clinical and preclinical data focused on the relationship between oncogenic drivers and immunological characteristics and discuss the future direction of immunotherapy in NSCLC patients harboring such genetic alterations.