Bacillus Calmette‑Gu�rin induces rapid gene expression changes in human bladder cancer cell lines that may modulate its survival

Abstract

Bacillus Calmette-Guérin (BCG) immunotherapy is the standard therapy for non-muscle invasive bladder cancer. The aim of the present study was to identify genes that are induced in response to BCG immunotherapy, as these may be potential biomarkers for the response to clinical therapy. To model clinical therapy, human bladder cancer cell lines were incubated with BCG (live or lyophilized BCG Connaught) for 2 h. RNA was extracted and evaluated by Representational Differential Analysis (RDA) and oligo arrays. Gene expression was confirmed by reverse transcription polymerase chain reaction on fresh cell lines with differential abilities to internalize BCG. The effect of 2 major BCG soluble proteins, antigen 85B (Ag85B) and Mycobacterium protein tyrosine phosphatase A (MptpA) and BCG Tice® on gene expression was also determined. GAPDH and β-actin, which are normally used as control genes, were upregulated by BCG. Therefore, the ribosomal RNA gene ribosomal protein S27a was used to normalize gene expression. The genes likely to be induced by BCG internalization and soluble factors were: GSTT2, MGST2, CCL20, TNFα, CCNE1 and IL10RB. Those induced by BCG membrane interactions and/or soluble factors were: MGST1, CXCL6, IL12A, CSF2, IL1β and TOLLIP. MptpA decreased GSTT2 expression, and Ag85B increased TNFα expression. The two BCG strains significantly increased GSTT2, TNFα and TOLLIP levels in MGH cells. However, in J82 cells there was a BCG strain-dependent difference in TNFα expression. An important outcome of the present study was the determination that neither GAPDH nor β-actin were suitable control genes for the analysis of BCG-induced gene expression. BCG Connaught and Tice® induced similar expression levels of genes in bladder cancer cell lines. BCG soluble proteins modulated gene expression and therefore may affect therapeutic outcomes. The genes identified may be novel biomarkers of the response to BCG therapy.

Identification of novel biomarkers based on lipid metabolism-related molecular subtypes for moderately severe and severe acute pancreatitis

“…MGST1 is considered a tumor marker, and its overexpression has been linked to a poor prognosis in several malignancies [ 48 – 50 ], and proposed as a potential therapeutic target for pancreatic cancer [ 51 ]. Additionally, it could serve as a biomarker to predict treatment efficacy and assess cancer risk [ 52 , 53 ]. MGST1 polymorphisms may also influence an individual’s susceptibility to specific cancers [ 54 ].…”

A signature of glucose metabolism and DNA methylation improves prognostic prediction for urinary bladder cancer

“…Among the 18 genes, FBP1 has been reported to serve as a potential biomarker for molecular subtypes of bladder cancer for its participation in glycolysis flux and gluconeogenesis [31]; MGST2 could be induced in bladder cancer cells by Bacillus Calmette-Guérin (BCG) internalization and thus it might act as a novel biomarker of the response to BCG immunotherapy for bladder cancer [32]; TXNIP negatively regulates bladder carcinogenesis by attenuating SDF-1-CXCR4-induced ERK activation [33]; ELF3 can protects bladder cancer cells from epithelial-mesenchymal transition [34]. These above are highly in accordance to our results, supporting the validity of our study strategy.…”

Current Development and Application of Anaerobic Glycolytic Enzymes in Urothelial Cancer

“…Interestingly, Juwita et al claimed that in two BC cell lines (RT4 and MGH), GAPDH was induced by Bacillus Calmette–Guerin, which is the standard therapy for non-muscle-invasive BC [ 101 ]. Although the specific mechanisms are still unclear, GAPDH is no longer suitable as a housekeeping gene for BC, as is in the case of gastric cancer [ 102 ].…”