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Life Science Alliance Sep 2024Decitabine and azacytidine are considered as epigenetic drugs that induce DNA methyltransferase (DNMT)-DNA crosslinks, resulting in DNA hypomethylation and damage....
Decitabine and azacytidine are considered as epigenetic drugs that induce DNA methyltransferase (DNMT)-DNA crosslinks, resulting in DNA hypomethylation and damage. Although they are already applied against myeloid cancers, important aspects of their mode of action remain unknown, highly limiting their clinical potential. Using a combinatorial approach, we reveal that the efficacy profile of both compounds primarily depends on the level of induced DNA damage. Under low DNMT activity, only decitabine has a substantial impact. Conversely, when DNMT activity is high, toxicity and cellular response to both compounds are dramatically increased, but do not primarily depend on DNA hypomethylation or RNA-associated processes. By investigating proteome dynamics on chromatin, we show that decitabine induces a strictly DNMT-dependent multifaceted DNA damage response based on chromatin recruitment, but not expression-level changes of repair-associated proteins. The choice of DNA repair pathway hereby depends on the severity of decitabine-induced DNA lesions. Although under moderate DNMT activity, mismatch (MMR), base excision (BER), and Fanconi anaemia-dependent DNA repair combined with homologous recombination are activated in response to decitabine, high DNMT activity and therefore immense replication stress induce activation of MMR and BER followed by non-homologous end joining.
Topics: Decitabine; DNA Damage; Humans; DNA Repair; DNA Methylation; Azacitidine; Antimetabolites, Antineoplastic; Cell Line, Tumor; DNA (Cytosine-5-)-Methyltransferases; Chromatin; DNA Modification Methylases
PubMed: 38906675
DOI: 10.26508/lsa.202302437 -
Cell Reports. Medicine Jun 2024Immune checkpoint inhibitors (ICIs) activate anti-cancer immunity by blocking T cell checkpoint molecules such as programmed death 1 (PD-1) and cytotoxic T... (Review)
Review
Immune checkpoint inhibitors (ICIs) activate anti-cancer immunity by blocking T cell checkpoint molecules such as programmed death 1 (PD-1) and cytotoxic T lymphocyte-associated protein 4 (CTLA-4). Although ICIs induce some durable responses in various cancer patients, they also have disadvantages, including low response rates, the potential for severe side effects, and high treatment costs. Therefore, selection of patients who can benefit from ICI treatment is critical, and identification of biomarkers is essential to improve the efficiency of ICIs. In this review, we provide updated information on established predictive biomarkers (tumor programmed death-ligand 1 [PD-L1] expression, DNA mismatch repair deficiency, microsatellite instability high, and tumor mutational burden) and potential biomarkers currently under investigation such as tumor-infiltrated and peripheral lymphocytes, gut microbiome, and signaling pathways related to DNA damage and antigen presentation. In particular, this review aims to summarize the current knowledge of biomarkers, discuss issues, and further explore future biomarkers.
PubMed: 38906149
DOI: 10.1016/j.xcrm.2024.101621 -
Cancer Epidemiology Jun 2024Serrated lesions and polyps (SP) are precursors of up to 30 % of colorectal cancers (CRC) through the serrated pathway. This often entails early BRAF mutations and...
BACKGROUND
Serrated lesions and polyps (SP) are precursors of up to 30 % of colorectal cancers (CRC) through the serrated pathway. This often entails early BRAF mutations and MLH1 hypermethylation leading to mismatch repair deficient (dMMR) CRC. We investigated predictors of dMMR CRC among patients with co-occurrence of CRC and SP to increase our knowledge on the serrated pathway.
METHODS
We used data from The Danish Pathology Registry and Danish Colorectal Cancer Groups Database from the period 2010-2021 to investigate risk factors for development of dMMR CRC. We used logistic regression models to identify difference in risk factors of developing dMMR CRC in comparison to CRC with proficient MMR (pMMR).
RESULTS
We included 3273 patients with a median age of 70.7 years [64.3,76.4] of which 1850 (56.5 %) were male. dMMR CRC was present in 592 patients (18.1 %), with loss of MLH1/PMS2 being most common. The risk of dMMR CRC was significantly higher in females OR 3.47 [2.87;4.20]. When adjusting for age, SP subtype, conventional adenomas (CA), anatomical location and lifestyle factors, female sex remained the strongest predictor OR 2.84 [2.27;3.56]. The presence of sessile serrated lesions with or without dysplasia was related to higher risk OR 1.60 [1.11;2.31] and OR 1.42 [1.11;1.82] respectively, while conventional adenomas constituted a lower risk OR 0.68 [0.55;0.84].
CONCLUSION
In conclusion we found several predictors of whom female sex had the strongest correlation with dMMR CRC in patients with SP.
PubMed: 38905781
DOI: 10.1016/j.canep.2024.102601 -
Vascular Jun 2024Although the medical field has made significant progress, there has been little improvement in the survival rate of patients with ruptured abdominal aortic aneurysms...
OBJECTIVES
Although the medical field has made significant progress, there has been little improvement in the survival rate of patients with ruptured abdominal aortic aneurysms (rAAAs). We implemented a protocol consisting of five strategies in the management of rAAA patients who underwent open repair surgery.
METHODS
The protocol comprised the following strategies: intentional hypotension <70 mmHg, lung first and kidney last policy (restricted fluid resuscitation and permissive oligoanuria), immediate postoperative extubation, free-water intake with active ambulation, and open abdomen with the routine second-look operation. The study included 13 patients (11 male) with a mean age of 75.5 ± 7.4 (range: 58-87) years who underwent the procedure from 2016 to 2018, with a mean follow-up of 40.1 ± 9.04 months. Five deteriorating to hemodynamic shock and decreased consciousness requiring intubation and ventilation prior to surgery were observed. Two of these patients required preoperative cardiopulmonary resuscitation (CPR).
RESULTS
All patients regained consciousness after surgery, including the two patients who required cardiopulmonary resuscitation. Immediate postoperative extubation was performed in nine patients, but two (22.2%) of them needed re-intubation due to ventilation/perfusion mismatch. Four patients underwent continuous renal replacement therapy, with three of them having anuria for up to 48 h after surgery. Two of these patients made a full recovery. Daily ambulation was carried out for a mean of 4.77 ± 3.5 (range 1-13) days with an open abdomen, during which no significant events were reported. Four cases of colon ischemia/necrosis were identified in the second-look operation, with two patients requiring Hartman's procedure and the other two undergoing left colon partial resection. There were two in-hospital mortalities (15.4%).
CONCLUSIONS
A protocol-based approach, through multidisciplinary team consensus and the development of optimal surgical strategies, could improve clinical outcomes for patients undergoing emergency surgery for rAAA. Further studies with larger sample sizes are needed to refine the protocols.
PubMed: 38905636
DOI: 10.1177/17085381241261752 -
JCO Global Oncology Jun 2024Genetic variants of ovarian cancer (OV) show ethnic differences, but data from the Chinese population are still insufficient. Here, we elucidate the inheritance...
PURPOSE
Genetic variants of ovarian cancer (OV) show ethnic differences, but data from the Chinese population are still insufficient. Here, we elucidate the inheritance landscape in Chinese patients with OV and examine the functional implications of a Chinese-enriched variant.
METHODS
Between 2015 and 2018, 373 consecutive patients with OV were prospectively enrolled. Variants of , other homologous recombination repair (HRR) genes, and DNA mismatch repair (MMR) genes were analyzed using next-generation sequencing. An enriched variant was identified, and its functional effects were examined using Cell Counting Kit-8, colony formation, transwell migration, and drug sensitivity assays.
RESULTS
Overall, 31.1% (116/373) of patients had at least one pathogenic or likely pathogenic germline variant. and accounted for 16.09% and 5.36%, respectively, with one patient having both variants. In addition, 32 (8.58%) patients carried other HRR gene variants, whereas three (0.8%) patients had MMR gene variants. The variant ranked third (8/373, 2.1%), and its rate was much higher than that in other populations. Remarkably, all eight patients harbored the K91fs variant (c.270_271dup, p.Lys91Ilefs*13) and demonstrated satisfactory platinum response and favorable prognosis. This variant confers enhanced sensitivity to poly (ADP-ribose) polymerase inhibitors in OV cells. However, the effects on platinum sensitivity were inconsistent across different cell lines. Against the background of the variant, K91fs variant showed increased sensitivity to cisplatin.
CONCLUSION
Our study revealed the inheritance landscape of OV and identified an enriched variant in Chinese patients with OV. This can serve as an important reference for OV management and a potential therapeutic target.
Topics: Humans; Female; Ovarian Neoplasms; Germ-Line Mutation; Middle Aged; DNA-Binding Proteins; Adult; Aged; Asian People; China; Prospective Studies; High-Throughput Nucleotide Sequencing; East Asian People
PubMed: 38905575
DOI: 10.1200/GO.23.00454 -
Virchows Archiv : An International... Jun 2024The current knowledge about the immunohistochemical features of adult granulosa cell tumor (AGCT) is mostly limited to the "traditional" immunohistochemical markers of...
The current knowledge about the immunohistochemical features of adult granulosa cell tumor (AGCT) is mostly limited to the "traditional" immunohistochemical markers of sex cord differentiation, such as inhibin, calretinin, FOXL2, SF1, and CD99. Knowledge about the immunohistochemical markers possibly used for predictive purpose is limited. In our study, we focused on the immunohistochemical examination of 290 cases of AGCT classified based on strict diagnostic criteria, including molecular testing. The antibodies used included 12 of the "diagnostic" antibodies already examined in previous studies, 10 antibodies whose expression has not yet been examined in AGCT, and 7 antibodies with possible predictive significance, including the expression of HER2, PD-L1, CTLA4, and 4 mismatch repair (MMR) proteins. The results of our study showed expression of FOXL2, SF1, CD99, inhibin A, calretinin, ER, PR, AR, CKAE1/3, and CAIX in 98%, 100%, 90%, 78%, 45%, 41%, 94%, 82%, 26%, and 9% of AGCT, respectively. GATA3, SATB2, napsin A, MUC4, TTF1, and CD44 were all negative. PTEN showed a loss of expression in 71% of cases and DPC4 in 4% of cases. The aberrant staining pattern (overexpression) of p53 was found in 1% (3/268) of cases, 2 primary tumors, and 1 recurrent case. Concerning the predictive markers, the results of our study showed that AGCT is microsatellite stable, do not express PD-L1, and are HER2 negative. The CTLA4 expression was found in almost 70% of AGCT tumor cells.
PubMed: 38904760
DOI: 10.1007/s00428-024-03854-0 -
Indian Journal of Pathology &... Jun 2024To investigate relationships between microsatellite instability (MSI) and the clinicopathological characteristics of colorectal cancer (CRC) to facilitate the provision...
BACKGROUND
To investigate relationships between microsatellite instability (MSI) and the clinicopathological characteristics of colorectal cancer (CRC) to facilitate the provision of targeted therapy and immunotherapy for CRC related to MSI, and provide a basis for better prognoses.
MATERIALS AND METHODS
Data were obtained from the information system of the Pathology Department of the Fourth Affiliated Hospital of Harbin Medical University, China, from January 01, 2021 to September 30, 2022. Clinicopathological information, including sex, age, tumor size, and associated expression of MSI, was collected.
RESULTS
CRC associated with MSI usually occurred in people aged over 50 years. It was related to tumor diameter, which was 5-10 cm at the most. Most tumors occurred in the right colon and were moderately to poorly differentiated. PCR detected 29 patients, including 24 cases of microsatellite stable (MSS), one case of MSI-low, and four cases of MSI-high. The expression of mismatch repair (MMR) protein in these 29 patients was also investigated via immunohistochemistry (IHC), which detected 25 cases of MSS and four cases of MSI-high. The consistency between IHC and PCR was 96.6%.
CONCLUSION
The expression of MMR is related to age, tumor diameter, tumor location, and tumor differentiation. It was not related to gender, lymphovascular and perineural invasion, lymph node metastasis, TNM stage, or P53 expression. The consistency between IHC and PCR was 96.6%.
PubMed: 38904458
DOI: 10.4103/ijpm.ijpm_651_23 -
Journal of Gastroenterology Jun 2024The optimal interval of colonoscopy (CS) surveillance in cases with Lynch syndrome (LS), and stratification according to the causative mismatch repair gene mutation, has...
BACKGROUND
The optimal interval of colonoscopy (CS) surveillance in cases with Lynch syndrome (LS), and stratification according to the causative mismatch repair gene mutation, has received much attention. To verify a feasible and effective CS surveillance strategy, we investigated the colorectal cancer (CRC) incidence at different intervals and the characteristics of precancerous colorectal lesions of LS cases.
METHODS
This retrospective multicenter study was conducted in Japan. CRCs and advanced adenomas (AAs) in 316 LS cases with germline pathogenic variants (path_) were analyzed according to the data of 1,756 registered CS.
RESULTS
The mean time interval for advanced CRCs (ACs) detected via CS surveillance was 28.7 months (95% confidence interval: 13.8-43.5). The rate of AC detection within (2.1%) and beyond 2 years (8.7%) differed significantly (p = 0.0003). AAs accounted for 43%, 46%, and 41% of lesions < 10 mm in size in the MLH1-, MSH2-, and MSH6-groups, respectively. The lifetime incidence of metachronous CRCs requiring intestinal resection for path_MLH1, path_MSH2, and path_MSH6 cases was 34%, 23%, and 14% in these cases, respectively. The cumulative CRC incidence showed a trend towards a 10-year delay for path_MSH6 cases as compared with that for path_MLH1 and path_MSH2 cases.
CONCLUSIONS
In cases with path_MLH1, path_MSH2, and path_MSH6, maintaining an appropriate CS surveillance interval of within 2 years is advisable to detect of the colorectal lesion amenable to endoscopic treatment. path_MSH6 cases could be stratified with path_MLH1 and MSH2 cases in terms of risk of metachronous CRC and age of onset.
PubMed: 38902413
DOI: 10.1007/s00535-024-02128-5 -
The Journal of International Medical... Jun 2024Breast cancer, particularly triple-negative breast cancer (TNBC), poses a significant global health burden. Chemotherapy was the mainstay treatment for TNBC patients...
BACKGROUND
Breast cancer, particularly triple-negative breast cancer (TNBC), poses a significant global health burden. Chemotherapy was the mainstay treatment for TNBC patients until immunotherapy was introduced. Studies indicate a noteworthy prevalence (0.2% to 18.6%) of mismatch repair protein (MMRP) deficiency in TNBC, with recent research highlighting the potential of immunotherapy for MMRP-deficient metastatic breast cancer. This study aims to identify MMRP deficiency in TNBC patients using immunohistochemistry.
METHODS
A retrospective cohort study design was used and included TNBC patients treated between 2015 and 2021 at King Hussein Cancer Center. Immunohistochemistry was conducted to assess MMRP expression.
RESULTS
Among 152 patients, 14 (9.2%) exhibited deficient MMR (dMMR). Loss of PMS2 expression was observed in 13 patients, 5 of whom showed loss of MLH1 expression. Loss of MSH6 and MSH2 expression was observed in one patient. The median follow-up duration was 44 (3-102) months. Despite the higher survival rate (80.8%, 5 years) of dMMR patients than of proficient MMR patients (62.3%), overall survival did not significantly differ between the two groups.
CONCLUSION
Approximately 9% of TNBC patients exhibit dMMR. dMMR could be used to predict outcomes and identify patients with TNBC who may benefit from immunotherapy.
Topics: Humans; Female; Triple Negative Breast Neoplasms; Middle Aged; Adult; Retrospective Studies; Mismatch Repair Endonuclease PMS2; Aged; DNA-Binding Proteins; DNA Mismatch Repair; MutL Protein Homolog 1; MutS Homolog 2 Protein; Biomarkers, Tumor; Survival Rate; Immunohistochemistry; Aged, 80 and over; Prognosis
PubMed: 38902203
DOI: 10.1177/03000605241259747 -
Zhonghua Wei Chang Wai Ke Za Zhi =... Jun 2024To analyze the differences in clinicopathological features of colon cancers and survival between patients with right- versus left-sided colon cancers. This was a...
[Effects of tumor location and mismatch repair on clinicopathological features and survival for non-metastatic colon cancer: A retrospective, single center, cohort study].
To analyze the differences in clinicopathological features of colon cancers and survival between patients with right- versus left-sided colon cancers. This was a retrospective cohort study. Information on patients with colon cancer from January 2016 to August 2020 was collected from the prospective registry database at Peking Union Medical College Hospital . Primary tumors located in the cecum, ascending colon, and proximal two-thirds of the transverse colon were defined as right-sided colon cancers (RCCs), whereas primary tumors located in the distal third of the transverse colon, descending colon, or sigmoid colon were defined as left-sided colon cancers (LCCs). Clinicopathological features were compared using the χ test or Mann-Whitney test. Survival was estimated by Kaplan-Meier curves and the log-rank test. Factors that differed significantly between the two groups were identified by multivariate survival analyses performed with the Cox proportional hazards function. One propensity score matching was performed to eliminate the effects of confounding factors. The study cohort comprised 856 patients, with TNM Stage I disease, 391 (45.7%) with Stage II, and 336 (39.3%) with Stage III, including 442 (51.6%) with LCC and 414 (48.4%) with RCC and 129 (15.1%). Defective mismatch repair (dMMR) was identified in 139 patients (16.2%). Compared with RCC, the proportion of men (274/442 [62.0%] vs. 224/414 [54.1%], χ=5.462, =0.019), body mass index (24.2 [21.9, 26.6] kg/m vs. 23.2 [21.3, 25.5] kg/m, =78,789.0, <0.001), and well/moderately differentiated cancer (412/442 [93.2%] vs. 344/414 [83.1%], χ=22.266, <0.001) were higher in the LCC than the RCC group. In contrast, the proportion of dMMR (40/442 [9.0%] vs. 99/414 [23.9%], χ=34.721, <0.001) and combined vascular invasion (106/442[24.0%] vs. 125/414[30.2%], χ=4.186, =0.041) were lower in the LCC than RCC group. The median follow-up time for all patients was 48 (range 33, 59) months. The log-rank test revealed no significant differences in disease-free survival (DFS) (=0.668) or overall survival (OS) (=0.828) between patients with LCC versus RCC. Cox proportional hazards model showed that dMMR was significantly associated with a longer DFS (HR=0.419, 95%CI: 0.204‒0.862, =0.018), whereas a higher proportion of T3-4 (HR=2.178, 95%CI: 1.089‒4.359, =0.028), N+ (HR=2.126, 95%CI: 1.443‒3.133, <0.001), and perineural invasion (HR=1.835, 95%CI: 1.115‒3.020, =0.017) were associated with poor DFS. Tumor location was not associated with DFS or OS (all >0.05). Subsequent analysis showed that RCC patients with dMMR had longer DFS than did RCC patients with pMMR (HR=0.338, 95%CI: 0.146‒0.786, =0.012). However, the difference in OS between the two groups was not statistically significant (HR=0.340, 95%CI:0.103‒1.119, =0.076). After propensity score matching for independent risk factors for DFS, the log-rank test revealed no significant differences in DFS (=0.343) or OS (=0.658) between patients with LCC versus RCC, whereas patient with dMMR had better DFS (=0.047) and OS (=0.040) than did patients with pMMR. Tumor location is associated with differences in clinicopathological features; however, this has no impact on survival. dMMR status is significantly associated with longer survival: this association may be stronger in RCC patients.
Topics: Humans; Male; Colonic Neoplasms; Retrospective Studies; Female; Middle Aged; DNA Mismatch Repair; Adenocarcinoma; Aged; Disease-Free Survival; Survival Rate; Cohort Studies; Prognosis; Kaplan-Meier Estimate; Proportional Hazards Models
PubMed: 38901992
DOI: 10.3760/cma.j.cn441530-20231019-00140