DNA Repair Pathways in Cancer Therapy and Resistance

DNA repair pathways are triggered to maintain genetic stability and integrity when mammalian cells are exposed to endogenous or exogenous DNA-damaging agents. The deregulation of DNA repair pathways is associated with the initiation and progression of cancer. As the primary anti-cancer therapies, ionizing radiation and chemotherapeutic agents induce cell death by directly or indirectly causing DNA damage, dysregulation of the DNA damage response may contribute to hypersensitivity or resistance of cancer cells to genotoxic agents and targeting DNA repair pathway can increase the tumor sensitivity to cancer therapies. Therefore, targeting DNA repair pathways may be a potential therapeutic approach for cancer treatment. A better understanding of the biology and the regulatory mechanisms of DNA repair pathways has the potential to facilitate the development of inhibitors of nuclear and mitochondria DNA repair pathways for enhancing anticancer effect of DNA damage-based therapy

Classification of Traditional Chinese Medicine Syndromes in Patients with Chronic Hepatitis B by SELDI-Based ProteinChip Analysis

Traditional Chinese medicine (TCM) syndrome, also called ZHENG, is the basis concept of TCM theory. It plays an important role in TCM practice. There are excess and deficiency syndromes in TCM syndrome. They are the common syndromes in chronic hepatitis B (CHB) patients. Here we aim to explore serum protein profiles and potential biomarkers for classification of TCM syndromes in CHB patients. 24 healthy controls and two cohorts of CHB patients of excess syndrome (n = 25) or deficiency syndrome (n = 19) were involved in this study. Protein profiles were obtained by surface-enhanced laser desorption ionization time-flight mass spectrometry (SELDI-TOF/MS) and multiple analyses were performed. Based on SELDI ProteinChip data, healthy controls and CHB patients or excess and deficiency syndromes in CHB patients were obviously differentiated by orthogonal partial least square (OPLS) analysis. Two significant serum proteins (m/z 4187 and m/z 5032) for classifying excess and deficiency syndromes were found. Moreover, the area under the receiver operating characteristic (ROC) curve was 0.887 for classifying excess and nonexcess syndrome, and 0.700 for classifying deficiency and nondeficiency syndrome, respectively. Therefore, the present study provided the possibility of TCM syndrome classification in CHB patients using a universally acceptable scientific approach

Identification of subtype-specific metastasis-related genetic signatures in sarcoma

Background: Sarcomas are heterogeneous rare malignancies constituting approximately 1% of all solid cancers in adults and including more than 70 histological and molecular subtypes with different pathological and clinical development characteristics. Method: We identified prognostic biomarkers of sarcomas by integrating clinical information and RNA-seq data from TCGA and GEO databases. In addition, results obtained from cell cycle, cell migration, and invasion assays were used to assess the capacity for Tanespimycin to inhibit the proliferation and metastasis of sarcoma. Results: Sarcoma samples (N = 536) were divided into four pathological subtypes including DL (dedifferentiated liposarcoma), LMS (leiomyosarcoma), UPS (undifferentiated pleomorphic sarcomas), and MFS (myxofibrosarcoma). RNA-seq expression profile data from the TCGA dataset were used to analyze differentially expressed genes (DEGs) within metastatic and non-metastatic samples of these four sarcoma pathological subtypes with DEGs defined as metastatic-related signatures (MRS). Prognostic analysis of MRS identified a group of genes significantly associated with prognosis in three pathological subtypes: DL, LMS, and UPS. ISG15, NUP50, PTTG1, SERPINE1, and TSR1 were found to be more likely associated with adverse prognosis. We also identified Tanespimycin as a drug exerting inhibitory effects on metastatic LMS subtype and therefore can serve a potential treatment for this type of sarcoma. Conclusions: These results provide new insights into the pathogenesis, diagnosis, treatment, and prognosis of sarcomas and provide new directions for further study of sarcoma

Molecular Mechanisms of Same TCM Syndrome for Different Diseases and Different TCM Syndrome for Same Disease in Chronic Hepatitis B and Liver Cirrhosis

Traditional Chinese medicine (TCM) treatment is based on the traditional diagnose method to distinguish the TCM syndrome, not the disease. So there is a phenomenon in the relationship between TCM syndrome and disease, called Same TCM Syndrome for Different Diseases and Different TCM Syndrome for Same Disease. In this study, we demonstrated the molecular mechanisms of this phenomenon using the microarray samples of liver-gallbladder dampness-heat syndrome (LGDHS) and liver depression and spleen deficiency syndrome (LDSDS) in the chronic hepatitis B (CHB) and liver cirrhosis (LC). The results showed that the difference between CHB and LC was gene expression level and the difference between LGDHS and LDSDS was gene coexpression in the G-protein-coupled receptor protein-signaling pathway. Therein genes GPER, PTHR1, GPR173, and SSTR1 were coexpressed in LDSDS, but not in LGDHS. Either CHB or LC was divided into the alternative LGDHS and LDSDS by the gene correlation, which reveals the molecular feature of Different TCM Syndrome for Same Disease. The alternatives LGDHS and LDSDS were divided into either CHB or LC by the gene expression level, which reveals the molecular feature of Same TCM Syndrome for Different Diseases

A 9 bp cis-element in the promoters of class I small heat shock protein genes on chromosome 3 in rice mediates L-azetidine-2-carboxylic acid and heat shock responses

In rice, the class I small heat shock protein (sHSP-CI) genes were found to be selectively induced by L-azetidine-2-carboxylic acid (AZC) on chromosome 3 but not chromosome 1. Here it is shown that a novel cis-responsive element contributed to the differential regulation. By serial deletion and computational analysis, a 9 bp putative AZC-responsive element (AZRE), GTCCTGGAC, located between nucleotides –186 and –178 relative to the transcription initiation site of Oshsp17.3 was revealed. Deletion of this putative AZRE from the promoter abolished its ability to be induced by AZC. Moreover, electrophoretic mobility shift assay (EMSA) revealed that the AZRE interacted specifically with nuclear proteins from AZC-treated rice seedlings. Two AZRE–protein complexes were detected by EMSA, one of which could be competed out by a canonical heat shock element (HSE). Deletion of the AZRE also affected the HS response. Furthermore, transient co-expression of the heat shock factor OsHsfA4b with the AZRE in the promoter of Oshsp17.3 was effective. The requirement for the putative AZRE for AZC and HS responses in transgenic Arabidopsis was also shown. Thus, AZRE represents an alternative form of heat HSE, and its interaction with canonical HSEs through heat shock factors may be required to respond to HS and AZC

Metformin plus megestrol acetate compared with megestrol acetate alone as fertility‐sparing treatment in patients with atypical endometrial hyperplasia and well‐differentiated endometrial cancer: a randomised controlled trial

Objective: To assess the efficacy of metformin in megestrol acetate (MA)-based fertility-sparing treatment for patients with atypical endometrial hyperplasia (AEH) and endometrioid endometrial cancer (EEC). Design: A randomised, single-centre, open-label, controlled trial conducted between October 2013 and December 2017. Setting: Shanghai OBGYN Hospital of Fudan University, China. Population: A total of 150 patients (18-45 years old) with primary AEH or well-differentiated EEC were randomised into an MA group (n = 74) and an MA plus metformin group (n = 76). Methods: Patients with AEH or EEC were firstly stratified, then randomised to receive MA (160 mg orally, daily) or MA (160 mg orally, daily) plus metformin (500 mg orally, three times a day). Main outcomes and measures: The primary efficacy parameter was the cumulate complete response (CR) rate within 16 weeks of treatment (16w-CR rate); the secondary efficacy parameters were 30w-CR rate and adverse events. Results: The 16w-CR rate was higher in the metformin plus MA group than in the MA-only group (34.3 versus 20.7%, odds ratio [OR] 2.0, 95% confidence interval [CI] 0.89-4.51, P = 0.09) but the difference was more significant in 102 AEH patients (39.6 versus 20.4%, OR 2.56, 95% CI 1.06-6.21, P = 0.04). This effect of metformin was also significant in non-obese (51.4 versus 24.3%, OR 3.28, 95% CI 1.22-8.84, P = 0.02) and insulin-sensitive (54.8 versus 28.6%, OR 3.04, 95% CI 1.03-8.97, P = 0.04) subgroups of AEH women. No significant result was found in secondary endpoints. Conclusion: As a fertility-sparing treatment, metformin plus MA was associated with a higher early CR rate compared with MA alone in AEH patients. Tweetable abstract For AEH patients, metformin plus MA might be a better fertility-sparing treatment to achieve a higher early CR rate compared with MA alone

Anti-cancer treatment within two weeks serves as a risk factor for clinical outcomes among cancer patients with COVID-19

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic has resulted in infections among patients with cancer. Our study aimed to investigate the potential adverse impact of anti-cancer treatments within 2 weeks of COVID-19 infection on clinical outcomes in patients with cancer.MethodsThis retrospective cohort study analyzed 70 cancer patients with COVID-19 infection from the First Hospital of Jilin University in Changchun City, Jilin Province, between March and June 2022. Data on demographic characteristics, vaccination status, COVID-19 clinical classification, symptoms, complications, tumor-related characteristics, laboratory examinations and medical interventions were extracted from electronic medical record. The primary outcome of our study was Intensive Care Unit (ICU) admission. Logistic regression model was performed to investigate the association between anti-cancer treatments within 2 weeks after COVID-19 infection and the risk of ICU admission.ResultsOf the 70 patients enrolled in this study, 37 received anti-cancer treatments within 2 weeks after COVID-19 infection. Patients receiving anti-cancer treatment were more likely to experience non-mild COVID-19, require oxygen therapy, develop acute respiratory distress syndrome (ARDS) and exhibit elevated inflammatory levels. The risk of ICU admission (P<0.001) and 30-day mortality after reverse transcriptase polymerase chain reaction (RT-PCR) negative conversion (P=0.007) was significantly higher in patients receiving anti-cancer treatments. In multivariate Logistic regression analysis, non-mild classification of COVID-19, anti-cancer treatments within 2 weeks and ECOG > 1were all independently associated with ICU admission after adjusting for confounder factors. The risk of ICU admission rose to 43.63 times (95% confidence interval=1.31–1452.94, P=0.035) in patients receiving anti-cancer treatments within 2 weeks.ConclusionAnti-cancer treatments within 2 weeks of COVID-19 infection increase the risk of ICU admission and 30-day mortality after RT-PCR negative conversion in patients with cancer. It may be recommended to postpone cancer-related treatments for more than 2 weeks in cancer patients with COVID-19 infection

Serotonin receptor HTR6-mediated mTORC1 signaling regulates dietary restriction-induced memory enhancement

Dietary restriction (DR; sometimes called calorie restriction) has profound beneficial effects on physiological, psychological, and behavioral outcomes in animals and in humans. We have explored the molecular mechanism of DR-induced memory enhancement and demonstrate that dietary tryptophan-a precursor amino acid for serotonin biosynthesis in the brain-and serotonin receptor 5-hydroxytryptamine receptor 6 (HTR6) are crucial in mediating this process. We show that HTR6 inactivation diminishes DR-induced neurological alterations, including reduced dendritic complexity, increased spine density, and enhanced long-term potentiation (LTP) in hippocampal neurons. Moreover, we find that HTR6-mediated mechanistic target of rapamycin complex 1 (mTORC1) signaling is involved in DR-induced memory improvement. Our results suggest that the HTR6-mediated mTORC1 pathway may function as a nutrient sensor in hippocampal neurons to couple memory performance to dietary intake