Combination of lysine-specific demethylase 6A (KDM6A) and mismatch repair (MMR) status is a potential prognostic factor in colorectal cancer

Inactivation of KDM6A promotes the progression of colorectal cancer by enhancing the glycolysis

KDM6A (lysine demethylase 6A) has been reported to undergo inactivating mutations in colorectal cancer, but its function in the progression of colorectal cancer has not been evaluated using animal models of colorectal cancer. In this study, we found that knocking out KDM6A expression in mouse intestinal epithelium increased the length of villus and crypt, promoting the development of AOM (azoxymethane)/DSS (dextran sulfate sodium salt)-induced colorectal cancer. On the other hand, knocking down KDM6A expression promoted the growth of colorectal cancer cells. In molecular mechanism studies, we found that KDM6A interacts with HIF-1α; knocking down KDM6A promotes the binding of HIF-1α to the LDHA promoter, thereby promoting LDHA expression and lactate production, enhancing glycolysis. Knocking down LDHA reversed the malignant phenotype caused by KDM6A expression loss. In summary, this study using animal models revealed that KDM6A loss promotes the progression of colorectal cancer through reprogramming the metabolism of the colorectal cancer cells, suggesting that restoring the function of KDM6A is likely to be one of the strategies for colorectal cancer treatment.

The emerging roles of histone demethylases in cancers

Modulation of histone methylation status is regarded as an important mechanism of epigenetic regulation and has substantial clinical potential for the therapy of diseases, including cancer and other disorders. The present study aimed to provide a comprehensive introduction to the enzymology of histone demethylases, as well as their cancerous roles, molecular mechanisms, therapeutic possibilities, and challenges for targeting them, in order to advance drug design for clinical therapy and highlight new insight into the mechanisms of these enzymes in cancer. A series of clinical trials have been performed to explore potential roles of histone demethylases in several cancer types. Numerous targeted inhibitors associated with immunotherapy, chemotherapy, radiotherapy, and targeted therapy have been used to exert anticancer functions. Future studies should evaluate the dynamic transformation of histone demethylases leading to carcinogenesis and explore individual therapy.

Histone modification: Biomarkers and potential therapies in colorectal cancer

The complex mechanism of colorectal cancer development is closely associated with epigenetic modifications and is caused by overexpression and/or inactivation of oncogenes. Histone modifying enzymes catalyze histone modifications to alter gene expression, which plays a crucial role in the development and progression of colorectal cancer. Currently, there is more frequent study on histone acetylation, methylation, and phosphorylation, and their mechanisms in colorectal cancer development are clearer. This article elaborates on the role of histone modification in epigenetics in colorectal cancer development and discusses recent advances in using it as biomarkers and therapeutic targets for the treatment of colorectal cancer. The review aims to demonstrate the significant role of histone modification as a new therapeutic target in colorectal cancer and provides insights into the novel diagnostic and therapeutic options it offers.

KDM6A promotes hepatocellular carcinoma progression and dictates lenvatinib efficacy by upregulating FGFR4 expression

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the major causes of death from cancer and has a very poor prognosis with few effective therapeutic options. Despite the approval of lenvatinib for the treatment of patients suffering from advanced HCC, only a small number of patients can benefit from this targeted therapy.

METHODS

Diethylnitrosamine (DEN)-CCL4 mouse liver tumour and the xenograft tumour models were used to evaluate the function of KDM6A in HCC progression. The xenograft tumour model and HCC cell lines were used to evaluate the role of KDM6A in HCC drug sensitivity to lenvatinib. RNA-seq and ChIP assays were conducted for mechanical investigation.

RESULTS

We revealed that KDM6A exhibited a significant upregulation in HCC tissues and was associated with an unfavourable prognosis. We further demonstrated that KDM6A knockdown remarkably suppressed HCC cell proliferation and migration in vitro. Moreover, hepatic Kdm6a loss also inhibited liver tumourigenesis in a mouse liver tumour model. Mechanistically, KDM6A loss downregulated the FGFR4 expression to suppress the PI3K-AKT-mTOR signalling pathway, leading to a glucose and lipid metabolism re-programming in HCC. KDM6A and FGFR4 levels were positively correlated in HCC specimens and mouse liver tumour tissues. Notably, KDM6A knockdown significantly inhibited the efficacy of lenvatinib therapy in HCC cells in vitro and in vivo.

CONCLUSIONS

Our findings revealed that KDM6A promoted HCC progression by activating FGFR4 expression and may be an essential molecule for influencing the efficacy of lenvatinib in HCC therapy.

Cancer treatment-related financial toxicity experienced by patients in low- and middle-income countries: a scoping review

PURPOSE

In the past decade, literature has called attention to financial toxicities experienced by cancer patients. Though studies have addressed research questions in high-income countries, there remains a paucity of in-depth reviews regarding low- and middle-income countries (LMICs). Our scoping review provides an overview of treatment-related financial toxicities experienced by cancer patients in LMICs.

METHODS

A systematic search was conducted in MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials. English peer-reviewed articles that (a) explored patients' experience with financial toxicity due to cancer treatment (b) were specific to LMICs as defined by the World Bank and (c) focused on qualitative data were included. Details regarding participants and main findings were extracted and synthesized.

RESULTS

The search yielded 6290 citations, and 42 studies across 3 low-income, 9 lower-middle-income and 8 upper-middle-income countries. Main themes identified included cancer patients encountered various material hardships, managed costs with different coping behaviours and experienced negative psychological responses to their financial burden. Higher levels of financial toxicities were associated with patient characteristics such as lower socio-economic status and lack of insurance, as well as patient outcomes such as lower quality of life.

CONCLUSION

Cancer patients in LMIC experience deleterious financial toxicities as a result of treatment. This comprehensive characterization of financial toxicities will better allow health systems to adopt evidence-based mitigation strategies to reduce the financial burden on patients.

DNA Damage Repair in Brain Tumor Immunotherapy

With the gradual understanding of tumor development, many tumor therapies have been invented and applied in clinical work, and immunotherapy has been widely concerned as an emerging hot topic in the last decade. It is worth noting that immunotherapy is nowadays applied under too harsh conditions, and many tumors are defined as “cold tumors” that are not sensitive to immunotherapy, and brain tumors are typical of them. However, there is much evidence that suggests a link between DNA damage repair mechanisms and immunotherapy. This may be a breakthrough for the application of immunotherapy in brain tumors. Therefore, in this review, first, we will describe the common pathways of DNA damage repair. Second, we will focus on immunotherapy and analyze the mechanisms of DNA damage repair involved in the immune process. Third, we will review biomarkers that have been or may be used to evaluate immunotherapy for brain tumors, such as TAMs, RPA, and other molecules that may provide a precursor assessment for the rational implementation of immunotherapy for brain tumors. Finally, we will discuss the rational combination of immunotherapy with other therapeutic approaches that have an impact on the DNA damage repair process in order to open new pathways for the application of immunotherapy in brain tumors, to maximize the effect of immunotherapy on DNA damage repair mechanisms, and to provide ideas and guidance for immunotherapy in brain tumors.

Combination of lysine-specific demethylase 6A (KDM6A) and mismatch repair (MMR) status is a potential prognostic factor in colorectal cancer

PURPOSE

To evaluate the relationship between the DNA mismatch repair (MMR) status and histone lysine-specific demethylase 6A (KDM6A) on the prognosis of colorectal cancer (CRC).

METHODS

About 594 patients with CRC from The Cancer Genome Atlas (TCGA) were enrolled in this retrospective study. Subsequently, a series of different classification tests for MMR status, cancer types, and target gene expression was conducted.

RESULTS

After filtering out the KDMs group of genes, we selected KDM6A as the target gene. A significant difference in the performance of KDM6A in tumor and normal tissues were confirmed. Our results showed a lower KDM6A expression, lower KDM6A exon expression, and higher KDM6A DNA methylation than their corresponding normal tissues in colon adenocarcinoma (COAD). Notably, the main MMR genes were highly expressed in tumor tissues than normal tissues both in COAD and rectum adenocarcinoma (READ). Moreover, proficient DNA mismatch repair (pMMR) was found to be an important poor prognostic factor in COAD (p = 0.0064) and the low KDM6A expression was an important factor for poor prognosis in READ (p = 0.0217). Based on these results, we consequently relate MMR status with KDM6A expression in predicting the prognosis of patients with CRC. Moreover, patients with pMMR exhibited a low KDM6A expression in COAD (p = 0.0250). Samples were divided into two groups based on the KDM6A expression. Interestingly, the group with low KDM6A expression showed no difference between pMMR and deficient DNA mismatch repair (dMMR) in prognosis, whereas the group with high KDM6A expression was closely related to MMR status in OS (p = 0.0082). Besides, COAD patients with high KDM6A expression and pMMR status had poor OS (p = 0.0082).

CONCLUSIONS

The KDM6A/MMR classification-based subtypes of low KDM6A expression/READ, high KDM6A expression/pMMR, and COAD/pMMR were associated with poor prognosis. This classification can be a novel prognostic approach in CRC.