Metabolic activity via 18F-FDG PET/CT is predictive of microsatellite instability status in colorectal cancer.

PURPOSE: Identification of microsatellite instability high (MSI-H) colorectal cancer (CRC) is crucial for screening patients most likely to benefit from immunotherapy. We aim to investigate whether the metabolic characteristics is related to MSI status and can be used to predict the MSI-H CRC. METHODS: A retrospective analysis was conducted on 420 CRC patients who were identified via [18F]fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography(CT) prior to therapy. Maximum standardized uptake (SUVmax), mean standardized uptake (SUVmean), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of the primary tumor were calculated and compared between MSI-H and microsatellite stability (MSS). Predictive factors of MSI status were selected from metabolic parameters and clinicopathological profiles via a multivariate analysis. RESULTS: Of 420 colorectal cancers, 44 exhibited a high incidence of MSI. Both MTV and TLG were significantly higher in MSI-H group compared with the MSS group (P = 0.004 and P = 0.010, respectively). Logistic regression analysis indicated that CRC with MSI-H were related to younger age (P = 0.013), primary lesion located at right hemi-colon (P < 0.001) and larger MTV on PET/CT imaging (P = 0.019). MTV more than 32.19 of colorectal cancer was linked to the presence of MSI (P = 0.019). CONCLUSION: Tumor metabolic burden were higher in MSI-H CRC which may be useful for predicting the MSI status of CRC patient and thus aid in determination of immunotherapy for patients with CRC.

Genetic alteration of Chinese patients with rectal mucosal melanoma.

BACKGROUND: Rectal mucosal melanoma (RMM) is a rare and highly aggressive disease with a poor prognosis. Due to the rarity of RMM, there are few studies focusing on its genetic mechanism. This retrospective study aimed to analyze the genetic spectrum and prognosis of RMM in China and lay a foundation for targeted therapy. METHODS: 36 patients with primary RMM from Peking University Cancer Hospital were enrolled in this study. The Next-generation sequencing (NGS) data of the tumor samples were fitted into the TruSight™ Oncology 500 (TSO500) Docker pipeline to detect genomic variants. Then, the univariate and multivariate Cox hazard analysis were performed to evaluate the correlations of the variants with the overall survival (OS), along with Kaplan-Meier and log-rank test to determine their significance. RESULTS: BRAF mutations, NRG1 deletions and mitotic index were significant prognostic factors in the univariate analysis. In multivariable analysis of the OS-related prognostic factors in primary RMM patients, it revealed 2 significant alterations: BRAF mutations [HR 7.732 (95%CI: 1.735-34.456), P = 0.007] and NRG1 deletions [HR 14.976 (95%CI: 2.305-97.300), P = 0.005]. CONCLUSIONS: This is the first study to show genetic alterations exclusively to Chinese patients with RMM. We confirmed genetic alterations of RMM differ from cutaneous melanoma (CM). Our study indicates that BRAF and NRG1 were correlated with a poor prognostic of RMM and may be potential therapeutic targets for RMM treatment.

Prognostic value of nucleotyping, DNA ploidy and stroma in high-risk stage II colon cancer.

BACKGROUND: Heterogeneity with respect to recurrence and survival in high-risk stage II colon cancer patients still exists, and further classification is urgently required. This study aimed to ascertain the prognostic value of DNA ploidy, stroma-tumour fraction and nucleotyping in the prognosis of high-risk stage II colon cancer. METHODS: A total of 188 high-risk stage II colon cancer patients received radical surgery in Peking University Cancer Hospital, from 2009 to 2015. Status of mismatch repair proteins in tumours was analysed using immunohistochemistry. DNA ploidy, stroma-tumour fraction and nucleotyping were estimated by automated digital imaging systems. RESULTS: Nucleotyping and DNA ploidy were significant prognostic factors, while stroma-tumour fraction were not significantly prognostic in the univariate analysis. In the multivariable model, the dominant contributory factor of disease-free survival was chromatin heterogeneous vs. chromatin homogeneous [HR 3.309 (95% CI: 1.668-6.564), P = 0.001]. CONCLUSIONS: Our study indicates that nucleotyping is an independent prognostic factor in high-risk stage II colon cancer. Therefore, it may help subdivide patients into different subgroups and give them different strategies for follow-up and treatment in the future.

Exploring prognostic values of DNA ploidy, stroma-tumor fraction and nucleotyping in stage II colon cancer patients.

PURPOSE: To assess the prognostic value of three novel biomarkers, DNA ploidy, stroma-tumor fraction, and nucleotyping, seeking for more accurate stratification in stage II colon cancer. METHODS: A total of 417 patients with complete follow up information were enrolled in this study and divided into three clinical risk groups. IHC was performed to examine MSI status. DNA ploidy, stroma and nucleotyping were estimated using automated digital imaging system. Kaplan-Meier survival curves, Cox proportional hazards regression models, and correlation analyses were carried out to process our data. RESULTS: In the whole cohort of stage II colon cancer, nucleotyping and DNA ploidy were significant prognostic factors on OS in univariate analyses. The combination of nucleotyping and DNA ploidy signified superior OS and DFS. Difference was not significant between low-stroma and high-stroma patients. In multivariable analyses, nucleotyping and the combination of nucleotyping and DNA ploidy were proven the dominant contributory factors for OS. In the low-risk group, we found the combination of nucleotyping and DNA ploidy as the independent prognostic factor statistically significant in both univariate and multivariable, while in the high-risk group, the nucleotyping. CONCLUSIONS: Our study has proven nucleotyping and the combination of DNA ploidy and nucleotyping as independent prognostic indicators, thus expanding the application of nucleotyping as a predictor from high risk stage II colon cancer to whole risks.

A review of the genus Pelenomus Thomson (Coleoptera: Curculionidae: Ceutorhynchinae) from China.

The genus Pelenomus Thomson from China is revised and six species are found occurring in China. Among them, P. curvatus, sp. nov. is described from Yunnan province, and four species are newly recorded from China: P waltoni (Boheman, 1843), P. canaliculatus (Fåhraeus, 1843), P. quadricorniger (Colonnelli, 1986) and P roelofsi (Hustache, 1916). Taxonomic diagnosis, habitus photos, detailed illustrations and distribution map of each species are provided, as well as a key to all the Chinese species. This study raised the number of Chinese Pelenomus from one to six species.

KRAS, NRAS, BRAF signatures, and MMR status in colorectal cancer patients in North China.

We assessed the clinicopathological features and prognostic values of KRAS, NRAS, BRAF, and DNA mismatch repair status in colorectal cancer (CRC) to provide real-world data in developing countries. We enrolled 369 CRC patients and analyzed the correlation between RAS/BRAF mutation, mismatch repair status with clinicopathological features, and their prognostic roles. The mutation frequencies of KRAS, NRAS, and BRAF were 41.7%, 1.6%, and 3.8%, respectively. KRAS mutations and deficient mismatch repair (dMMR) status were associated with right-sided tumors, aggressive biological behaviors, and poor differentiation. BRAF (V600E) mutations are associated with well-differentiated and lymphovascular invasion. The dMMR status predominated in young and middle-aged patients and tumor node metastasis stage II patients. dMMR status predicted longer overall survival in all CRC patients. KRAS mutations indicated inferior overall survival in patients with CRC stage IV. Our study showed that KRAS mutations and dMMR status could be applied to CRC patients with different clinicopathological features.

Folate-Receptor Positive Circulating Tumor Cell Is a Potential Diagnostic Marker of Prostate Cancer.

Folate-receptor positive circulating tumor cells (FR+CTCs) shows an important role in the diagnosis and dynamic monitoring for many solid tumors; however, the application of FR+CTCs in prostate cancer remains unclear. We explored the potential application of FR+CTCs in this retrospective study. The levels of FR+CTCs were detected in 30 prostate cancer patients and 7 bladder cancer patients in Peking University Cancer Hospital from August 2017 to August 2021. Clinical and pathology data were collected. One-way ANOVA was used to compare the difference in FR+CTCs levels in patients with prostate cancer, bladder cancer, and benign disease. The area under the receiver operating curve (AUROC) was used to compare the accuracy of FR+CTCs and tPSA in the diagnosis of prostate cancer. We found that levels of FR+CTCs were significantly higher in cancer patients (both prostate and bladder cancer) than in patients with benign urinary disease (p < 0.001). Besides, FR+CTCs level was consistently high in the prostate cancer patients with different tPSA levels (p < 0.001), and it was significantly higher in the patients with f/tPSA levels <0.16 than in those patients with f/tPSA levels >0.16 (12.20 ± 1.31 vs. 8.73 ± 0.92 FU/3 ml, p = 0.043). The diagnosis efficiency of FR+CTCs is better than the tPSA in prostate cancer patients with tPSA <10 ng/ml (0.871 vs. 0.857). In the prostate cancer patients with tPSA <10 ng/ml and f/tPSA <0.16, a combination of FR+CTCs and tPSA (AUROC, 0.934) further increased the diagnosis efficiency of each of these biomarkers alone (FR+CTCs, 0.912; tPSA, 0.857). Therefore, FR+CTCs could serve as an early diagnosis marker in the prostate cancer patients with uncertain tPSA levels.

RBM10 Deficiency Is Associated With Increased Immune Activity in Lung Adenocarcinoma.

INTRODUCTION: RBM10 is one of the frequently mutated genes in lung adenocarcinoma (LUAD). Previous studies have confirmed that RBM10 could suppress the disease progression and cell proliferation in LUAD, but its loss-of-function mutations are more frequent in early-stage disease and decrease with the advancement of the clinical stage. This is contradictory to its role of tumor suppressor. Here, we conducted a systematic analysis to elucidate whether there was other potential biological significance of RBM10 deficiency during the progression of LUAD. MATERIALS AND METHODS: The whole exome sequencing data of 39 tumor samples from early-stage LUADs (GGN cohort) and genomic and transcriptome data of the Cancer Genome Atlas (TCGA) LUAD cohort (TCGA_LUAD cohort) and a Chinese LUAD cohort (CHOICE_ADC cohort) were first obtained. Systematic bioinformatic analyses were then conducted to determine gene expression signature, immune infiltration levels and predicted immunotherapy response. Immunohistochemistry (IHC) was also conducted to validate the result of immune infiltration. RESULTS: The mutation rate of RBM10 was significantly higher in the GGN cohort than that in the TCGA_LUAD and CHOICE_ADC cohorts. In both TCGA_LUAD and CHOICE_ADC cohorts, multiple immune related pathways were markedly enriched in RBM10 deficient group. Further analyses showed that tumors with RBM10 mutations displayed higher TMB, and LUADs with RBM10 deficiency also showed higher HLA expression levels, including many HLA class I and II molecules. Additionally, many immune cells, including myeloid dendritic cells, macrophages, neutrophils and CD8+T cells, showed higher infiltration levels in LUADs with RBM10 deficiency. Finally, some immune checkpoint molecules, such as PD-L1 and TIM-3, were highly expressed in RBM10 deficient population and the predicted immunotherapy response was calculated through TIDE algorithm, showing that IFNG expression, MSI score and CD8 expression were higher in RBM10 deficient group, while MDSC and M2 macrophage were lower in RBM10 deficient group. CONCLUSION: Our study demonstrates that RBM10 deficient LUADs show higher HLA expression and immune cell infiltration, and some immune checkpoint molecules are also highly expressed. In brief, RBM10 deficiency could enhance anti-tumor immunity in LUAD.

Automated assessment of DNA ploidy, chromatin organization, and stroma fraction to predict prognosis and adjuvant therapy response in patients with stage II colorectal carcinoma.

DNA ploidy, tumor stroma, and chromatin organization have important implications in tumorigenesis and patient outcome. Automated image cytometry tools were developed to quantitatively measure DNA ploidy (P), stroma fraction (S), and chromatin organization or Nucleotyping (N). This study aimed to discover their clinical value in different stages of colorectal cancer (CRC) in a Chinese patient population. A total of 496 CRC patients of stages I, II, and LMCRC (liver metastatic CRC) were enrolled in this study. Stage II CRC patients with diploidy, low-stroma, or chromatin homogenous status predicted significantly higher 5-year OS and DFS. We constructed a PSN-panel enabled the stage II patients to be further stratified into low-, middle-, high-risk groups, the 5-year OS (89.5% vs 67.9% vs 60.9%, P<0.001) and DFS (86.0% vs 62.3% vs 53.6%, P<0.001) were stratified significantly. In addition, when combined the PSN-panel with T stage or MSS status in stage II patients, the PSN-low risk patients showed significant longer 5-year OS and DFS than the PSN-high risk patients in T3 (OS: 86.3% vs 65.3%, P=0.015; DFS: 83.5 vs 59.8%, P=0.013) or MSS (OS: 86.4% vs 63.9%, P=0.005; DFS: 85.5 vs 57.8%, P=0.003) patients. Finally, in the group of stage II patients with at least one high-risk factor (non-diploidy, high-stroma, chromatin heterogenous), patients who received adjuvant therapy showed significantly longer OS (72.1% vs 48.3%, P=0.007) and DFS (64.5% vs 43.9%, P=0.015) than those who did not receive adjuvant therapy. In contrast, P, S, N couldn't predict the prognosis of stage I and LMCRC patients. Overall, our data demonstrate that the PSN panel is an accurate prognostic tool that can guide treatment decisions for Chinese stage II CRC patients.

Aberrant promoter methylation of p16(INK4a) and O(6)-methylguanine-DNA methyltransferase genes in workers at a Chinese uranium mine.

To find the possible association of gene methylation of p16(INK4a) and O(6)-Methylguanine-DNA Methyltransferase (O(6)-MGMT) with occupational exposure to radon, 91 male miners from a uranium mine in China were divided into 4 groups according to the cumulative doses of radon exposure from 2 to 425 WLM (working-level months), and aberrant promoter methylation of p16(INK4a) and O(6)-MGMT genes in sputum samples was determined by a specific PCR assay. The results revealed that the methylated rates of 16(INK4a) gene (z=2.844, P=0.005) and O(6)-MGMT gene (z=3.034, P=0.002), and the total methylated rate of these two genes (z=3.859, P=0.0001) increased significantly with the cumulative doses of radon among the miners. This methylation could be applied as a potential marker for the detection of early DNA damage induced by occupational radon exposure.

[p16 and MGMT gene methylation in sputum cells of uranium workers].

OBJECTIVE: To study the methylation of O-6-methylguanine-DNA methyltransferase (MGMT) and p16 gene in the sputum cells of radon-exposed population. To provide the experimental base for finding the molecular biomarker of the high risk population of the radon-induced lung cancer. METHODS: 91 radon-exposed workers were divided into 4 groups, high dosage group (> 120 WLM), middle dosage group (between 60 and 120 WLM), low dosage group (between 30 and 60 WLB) and lower dosage group (between 2 and 30 WLM) according to the accumulated exposure dosage of the radon daughters. The abnormal methylation of p16 and MGMT gene in the sputum cells of the population in the four groups was detected with the methylation specific PCR (MSP). RESULTS: There was significantly upward trend for the p16 gene methylation rate (0.00%-20.00%), the MGMT gene methylation rate (0.00%-28.00%) and the total methylation rate (0.00%-40.00%) with the increase of the accumulated exposure dosage of the radon daughters (P < 0.01). CONCLUSION: The methylation of p16 and MGMT gene is related to the accumulate exposure dosage of the radon daughters.