Expression of cyclin-dependent kinase 9 is positively correlated with the autophagy level in colon cancer.

BACKGROUND: Cyclin-dependent kinase 9 (CDK9) expression and autophagy in colorectal cancer (CRC) tissues has not been widely studied. CDK9, a key regulator of transcription, may influence the occurrence and progression of CRC. The expression of autophagy-related genes BECN1 and drug resistance factor ABCG2 may also play a role in CRC. Under normal physiological conditions, autophagy can inhibit tumorigenesis, but once a tumor forms, autophagy may promote tumor growth. Therefore, understanding the relationship between autophagy and cancer, particularly how autophagy promotes tumor growth after its formation, is a key motivation for this research. AIM: To investigate the relationship between CDK9 expression and autophagy in CRC, assess differences in autophagy between left and right colon cancer, and analyze the associations of autophagy-related genes with clinical features and prognosis. METHODS: We collected tumor tissues and paracarcinoma tissues from colon cancer patients with liver metastasis to observe the level of autophagy in tissues with high levels of CDK9 and low levels of CDK9. We also collected primary tissue from left and right colon cancer patients with liver metastasis to compare the autophagy levels and the expression of BECN1 and ABCG2 in the tumor and paracarcinoma tissues. RESULTS: The incidence of autophagy and the expression of BECN1 and ABCG2 were different in left and right colon cancer, and autophagy might be involved in the occurrence of chemotherapy resistance. Further analysis of the relationship between the expression of autophagy-related genes CDK9, ABCG2, and BECN1 and the clinical features and prognosis of colorectal cancer showed that the high expression of CDK9 indicated a poor prognosis in colorectal cancer. CONCLUSION: This study laid the foundation for further research on the combination of CDK9 inhibitors and autophagy inhibitors in the treatment of patients with CRC.

Role of deubiquitinase JOSD2 in the pathogenesis of esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a deadly malignancy with limited treatment options. Deubiquitinases (DUBs) have been confirmed to play a crucial role in the development of malignant tumors. JOSD2 is a DUB involved in controlling protein deubiquitination and influencing critical cellular processes in cancer. AIM: To investigate the impact of JOSD2 on the progression of ESCC. METHODS: Bioinformatic analyses were employed to explore the expression, prognosis, and enriched pathways associated with JOSD2 in ESCC. Lentiviral transduction was utilized to manipulate JOSD2 expression in ESCC cell lines (KYSE30 and KYSE150). Functional assays, including cell proliferation, colony formation, drug sensitivity, migration, and invasion, were performed, revealing the impact of JOSD2 on ESCC cell lines. JOSD2's role in xenograft tumor growth and drug sensitivity in vivo was also assessed. The proteins that interacted with JOSD2 were identified using mass spectrometry. RESULTS: Preliminary research indicated that JOSD2 was highly expressed in ESCC tissues, which was associated with poor prognosis. Further analysis demonstrated that JOSD2 was upregulated in ESCC cell lines compared to normal esophageal cells. JOSD2 knockdown inhibited ESCC cell activity, including proliferation and colony-forming ability. Moreover, JOSD2 knockdown decreased the drug resistance and migration of ESCC cells, while JOSD2 overexpression enhanced these phenotypes. In vivo xenograft assays further confirmed that JOSD2 promoted tumor proliferation and drug resistance in ESCC. Mechanistically, JOSD2 appears to activate the MAPK/ERK and PI3K/AKT signaling pathways. Mass spectrometry was used to identify crucial substrate proteins that interact with JOSD2, which identified the four primary proteins that bind to JOSD2, namely USP47, IGKV2D-29, HSP90AB1, and PRMT5. CONCLUSION: JOSD2 plays a crucial role in enhancing the proliferation, migration, and drug resistance of ESCC, suggesting that JOSD2 is a potential therapeutic target in ESCC.

RING finger protein 128 (RNF128) regulates malignant biological behaviors of colorectal cancer cells via PI3K/AKT signaling pathway.

This study was designed and conducted to clarify the impact of RNF128 expression on malignant biological behaviors of colorectal cancer (CRC) cells and the underlying mechanism. The expression of RNF128 in CRC tissues was analyzed using mRNA sequencing data of TCGA database and was validated by Western blot assay. The experimental studies on biological functions of RNF128 in vitro were conducted to assess its impact on the proliferation, apoptosis, and metastasis of CRC cells. Furthermore, tumor xenograft models in nude mice were established to investigate the relationship between RNF128 expression and tumor growth in vivo. The expression levels of both RNF128 mRNA and protein were significantly increased in CRC tissues (p < .001). The knockdown of RNF128 markedly suppressed the malignant phenotype of HCT116 and SW480 cells in vitro, including cell growth, antiapoptosis, migration, and invasion (p < .001). On the other hand, knockdown of RNF128 exerted a remarkable effect on the growth inhibition of tumor xenografts in vivo (p < .001). Further investigation revealed that RNF128 knockdown lead to a significant decrease in the expression of p-AKT and p-PI3K protein. More importantly, the proliferative, antiapoptotic, metastatic abilities of RNF128-knockdown cells were markedly increased by 740 Y-P treatment (p < .001). These findings further suggested that PI3K/AKT signaling pathway played a key role in RNF128-mediated aggressive phenotype of CRC cells. RNF128 functions as a tumor promoter in the pathogenesis of CRC via regulating PI3K/AKT pathway, and it could be a valuable target for CRC treatment.

Prognosis model of colorectal cancer patients based on NOTCH3, KMT2C, and CREBBP mutations.

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers. The aim of our study was to explore its related mutations, identify novel mutation markers, and construct predictive models for postoperative CRC patients, so as to provide evidence for the diagnosis, treatment, and prognosis of CRC. METHODS: A total 50 CRC patients were collected, and the mutations in tissue samples were detected through next-generation sequencing (NGS). Meanwhile, 246 CRC cases with complete mutation data were downloaded from The Cancer Genome Atlas (TCGA) database. Afterwards, the co-mutations in both clinical and TCGA cohorts were identified, and the high-frequency mutation genes were selected. Subsequently, functional enrichment analysis was performed, and overall survival (OS) and progression-free survival (PFS) predictive models were constructed. RESULTS: In all, 18 out of 238 co-mutation genes mutated in at least 20% of the samples and were selected out as common high-frequency mutation genes. They were significantly enriched in 460 Gene Ontology (GO) terms and 87 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways (P<0.05), which were closely related to the occurrence and development of CRC. Among the 18 genes, NOTCH3, histone lysine methyltransferase 2C (KMT2C), and cAMP-response element binding protein-BP (CREBBP) were respectively associated with tumor position, stage, and PFS (P<0.05), and could be considered as potential biomarkers of CRC. Finally, OS and PFS predictive models were constructed and verified using the 50 clinical cases, with both models demonstrating high fitting degrees useful for predicting the OS and PFS of CRC patients. CONCLUSIONS: NOTCH3, KMT2C, and CREBBP were found to be prospective biomarkers for the diagnosis and prognosis of CRC. The prognosis prediction models had high sensitivity and could be used to predict the OS and PFS of CRC patients.

Ectopic expression of CNN2 of colon cancer promotes cell migration.

BACKGROUND: Calponin is an actin filament-associated regulatory protein originally identified in smooth muscle cells. Three homologous have been identified in vertebrate species, but little functional characterization of potential activities in cancer has been performed. In this study, we determined the levels of CNN2 in colon cancer cell lines and determined the effects of this protein by increasing expression. METHODS: We used IHC and RT-PCR to measure CNN2 expression in colon cancer tissues and normal tissues and found increased expression levels in cancer tissues. We used viral vectors to decrease the level of CNN2 in the SW480 colon cancer cell line and found that silencing of CNN2 inhibited cell invasion. We detected potential protein interactions in signal pathways by western bolt analysis. To confirm the effect of CNN2 on cell invasion, we increased CNN2 expression in the SW620 cell line and observed increased invasion increased expression levels of associated proteins. RESULTS: High-expression levels of CNN2 were detected in cancer tissues. Silencing CNN2 inhibited cell invasion, down-regulated N-cadherin (N-CA) and C-myc proteins, and up-regulated E-cadherin (E-CA), suggesting that CNN2 promotes colon cancer cell invasion. Increasing CNN2 levels in the SW620 cell line showed the opposite results. CONCLUSIONS: CNN2 may act to promote colon cancer.

Targeting BCRP/ABCG2 by RNA interference enhances the chemotherapy sensitivity of human colon cancer side population cells.

Relapse and metastasis are frequent in colon cancer and may be linked to stem cell characteristics. This study isolated side population (SP) cells from a colon cancer cell line (Colo-320) and examined their self-renewal and differentiation abilities. Compared to non-SP (NSP) cells, SP colon cancer cells were more tumorigenic in vivo and exhibited more invasive characteristics and a greater ability to form colonies. Additionally, more cells were in G0/G1 phase and more highly expressed the multidrug resistance protein BCRP/ABCG2. We achieved enhanced chemotherapy sensitivity by transfecting SP cells with a hairpin-like, small interfering RNA (siRNA) eukaryotic expression plasmid targeting BCRP/ABCG2.

Adjuvant interferon for early or late recurrence of hepatocellular carcinoma and mortality from hepatocellular carcinoma following curative treatment: A meta-analysis with comparison of different types of hepatitis.

Adjuvant interferon (IFN) therapy following curative treatment for hepatocellular carcinoma (HCC) has been extensively investigated; however, the clinical benefits with different hepatitis backgrounds remain unclear. Medline, Embase, PubMed and the Cochrane Library databases were searched to identify randomized trials and cohort studies that enrolled HCC patients who received curative surgery or ablation therapy followed by IFN and control subjects; the studies were required to include data on early or late recurrence and mortality rates of HCC. Hepatitis B virus (HBV) associated with HCC (HBV-HCC) and hepatitis C virus (HCV) associated with HCC (HCV-HCC) were separately analyzed and recurrence, mortality and clinicopathological factors were compared. A total of 14 studies (9 randomized trials and 5 cohort studies, including 1,385 patients in total) were eligible for meta-analysis. IFN was found to decrease mortality and early recurrence rates, but exerted no effect on late recurrence rate. The effect of IFN differed between HBV-HCC and HCV-HCC cases. In HCV-HCC, IFN significantly reduced mortality as well as recurrence rates. However, in HBV-HCC patients, IFN reduced mortality rather than recurrence rates, although it also reduced the recurrence rate in certain subgroups. In conclusion, the effect of adjuvant IFN on postoperative recurrence differed between HBV-HCC and HCV-HCC cases; therefore, different strategies with adjuvant IFN should be used to treat HCC with different hepatitis backgrounds.