Drug resistance is a major hurdle in cancer treatment and a key cause of poor prognosis. Epitranscriptomics and epiproteomics are crucial in cell proliferation, migration, invasion, and epithelial–mesenchymal transition. In recent years, epitranscriptomic and epiproteomic modification has been investigated on their roles in overcoming drug resistance. In this review article, we summarized the recent progress in overcoming cancer drug resistance in three novel aspects: (i) mRNA modification, which includes alternative splicing, A-to-I modification and mRNA methylation; (ii) noncoding RNAs modification, which involves miRNAs, lncRNAs, and circRNAs; and (iii) posttranslational modification on molecules encompasses drug inactivation/efflux, drug target modifications, DNA damage repair, cell death resistance, EMT, and metastasis. In addition, we discussed the therapeutic implications of targeting some classical chemotherapeutic drugs such as cisplatin, 5-fluorouridine, and gefitinib via these modifications. Taken together, this review highlights the importance of epitranscriptomic and epiproteomic modification in cancer drug resistance and provides new insights on potential therapeutic targets to reverse cancer drug resistance.

Background: Congenital heart disease (CHD) is the most common birth defect and affects nearly 1% of newborns. The aetiology of CHD is largely unknown and only a small percentage can be assigned to environmental risk factors such as maternal diseases or exposure to mutagenic agents during pregnancy. Chromosomal imbalances have been identified in many forms of syndromic CHD, but very little is known about the impact of DNA copy number changes in non-syndromic CHD. Method: A sub-megabase resolution array comparative genome hybridisation (CGH) screen was carried out on 105 patients with CHD as the sole abnormality at the time of diagnosis. Results: There were 18 chromosomal changes detected, which do not coincide with common DNA copy number variants, including one de novo deletion, two de novo duplications and eight familial copy number variations (one deletion and seven duplications). Conclusions: Our data show that submicroscopic deletions and duplications play an important role in the aetiology of this condition, either as direct causes or as genetic risk factors for CHD. These findings have immediate consequences for genetic counselling and should pave the way for the elucidation of the pathogenetic mechanisms underlying CHD.

Despite extensive progress in treatment for cancer in recent decades, the early diagnosis for gastric cancer (GC) and colorectal cancer (CRC) remains poor. In this study, we explore the diagnostic value of joint detection of thymidine kinase 1 (TK1), carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA 19-9) and carbohydrate antigen 72-4 (CA 72-4) in the diagnosis of GC and CRC, and to evaluated the relationship between TK1 expression and clinical pathological characteristics in the patients. Serum TK1, CA 19-9, CA 72-4 and CEA levels were measured in 169 patients with GC, 344 patients with CRC and 75 healthy controls using electro-chemiluminescence. The TK1 concentration was significantly higher in patients with cancer than in healthy controls and patients with clinical stage Ⅲ+Ⅳ had higher TK1 levels than clinical stage Ⅰ+Ⅱ (P<0.05). The levels of TK1 is significantly associated with tumor stage, lymph node metastasis, distant metastasis, tumor differentiation and age (P0.05). Moreover, the AUCs varied significantly between the combination tests and single biomarker tests (Z test, P<0.01). In conclusion, serum TK1 may be an independent tumor marker for GC and CRC patients, and the combination of TK1, CA 19-9 and CA 72-4 and CEA performed even better. This study suggests that combination detection of four tumor markers may prove to be useful for the diagnosis of GC and CRC.

Aim: We aimed to develop and validate a comprehensive nomogram containing pre-treatment plasma HSP90AA1 to predict the risk of breast cancer onset and metastasis.Methods: We assessed the expression of HSP90s in breast cancer patients using an online database. To verify the results, 677 patients diagnosed with breast cancer and 146 patients with benign breast disease between 2014 and 2019 were selected from our hospital and were divided into cancer risk and metastasis risk cohorts. We focused on HSP90AA1 to elucidate the risks of onset and metastasis in the cohorts.Results: Expression levels of HSP90AA1, HSP90AA2, HSP90AB1, HSP90B1, and TRAP1 were linked to disease progression. Survival analysis using the GEPIA and OncoLnc databases indicated that the upregulation of HSP90AA1 and HSP90AB1 was related to poor overall survival. In the cancer risk cohort, carcinoembryonic antigen (CEA), carbohydrate antigen 153 (CA153), HSP90AA1, T cells%, natural killer cells%, B cells%, neutrophil count, monocyte count, and d-dimer were incorporated into the nomogram. A high Harrell’s concordance index (C-index) value of 0.771 [95% confidence interval (CI), 0.725–0.817] could still be reached in the interval validation. In the metastasis risk cohort, predictors contained in the prediction nomogram included the use of CEA, CA153, HSP90AA1, carbohydrate antigen 125 (CA125), natural killer cells%, B cells%, platelet count, monocyte count, and d-dimer. The C-index was 0.844 (95% CI, 0.801–0.887) and it was well-calibrated. HSP90AA1 raised net clinical benefit of breast cancer onset and metastasis risk prediction nomogram in a range of risk thresholds (5–92%) and (1–90%).Conclusion: Our study revealed that pretreatment plasma HSP90AA1 combined with other markers could conveniently predict the risk of breast cancer onset and metastasis.

Epigallocatechin-3-gallate (EGCG) has been shown to inhibit the growth and induce apoptosis of certain cancer cells. The aim of this study was to determine the role of EGCG in hepatocellular carcinoma (HCC) and the underlying mechanism(s) thereof. MTT assay was used to determine the cell growth inhibition by EGCG. Apoptosis induced by EGCG was investigated by both AO/EB staining and flow cytometry. The cell cycle distribution was analyzed by flow cytometry. The mRNA levels of the AKT pathway were analyzed by quantitative PCR. The expression of AKT and its phosphorylation at Ser473 were detected by western blotting. The IC50 of EGCG at 48 h for HepG2, SMMC7721 and SK-hep1 cells were 74.7, 59.6 and 61.3 µg/ml, respectively. Significantly higher proportion of SMMC7721 cells entered the S phase upon treatment with EGCG for 48 h compared with control cells. EGCG decreased the mRNA levels of PI3K, AKT and NF-κB. The protein levels of AKT decreased and its phosphorylation at Ser473 was downregulated with EGCG treatment. EGCG inhibited growth by affecting the cell cycle and induced apoptosis in different HCC cells by downregulating PI3K/AKT activity. The results suggest the potential of EGCG as an anticancer agent in the prevention or treatment of HCC.