Metabolic adaptation is considered an emerging hallmark of cancer, whereby cancer cells exhibit high rates of glucose consumption with consequent lactate production. To ensure rapid efflux of lactate, most cancer cells express high levels of monocarboxylate transporters (MCTs), which therefore may constitute suitable therapeutic targets. The impact of MCT inhibition, along with the clinical impact of altered cellular metabolism during prostate cancer (PCa) initiation and progression, has not been described. Using a large cohort of human prostate tissues of different grades, in silico data, in vitro and ex vivo studies, we demonstrate the metabolic heterogeneity of PCa and its clinical relevance. We show an increased glycolytic phenotype in advanced stages of PCa and its correlation with poor prognosis. Finally, we present evidence supporting MCTs as suitable targets in PCa, affecting not only cancer cell proliferation and survival but also the expression of a number of hypoxia-inducible factor target genes associated with poor prognosis. Herein, we suggest that patients with highly glycolytic tumours have poorer outcome, supporting the notion of targeting glycolytic tumour cells in prostate cancer through the use of MCT inhibitors.

Prostate cancer (PCa) is one of the most incident cancers worldwide but clinical and pathological parameters have limited ability to discriminate between clinically significant and indolent PCa. Altered expression of histone methyltransferases and histone methylation patterns are involved in prostate carcinogenesis. SMYD3 transcript levels have prognostic value and discriminate among PCa with different clinical aggressiveness, so we decided to investigate its putative oncogenic role on PCa.We silenced SMYD3 and assess its impact through in vitro (cell viability, cell cycle, apoptosis, migration, invasion assays) and in vivo (tumor formation, angiogenesis). We evaluated SET domain's impact in PCa cells' phenotype. Histone marks deposition on SMYD3 putative target genes was assessed by ChIP analysis.Knockdown of SMYD3 attenuated malignant phenotype of LNCaP and PC3 cell lines. Deletions affecting the SET domain showed phenotypic impact similar to SMYD3 silencing, suggesting that tumorigenic effect is mediated through its histone methyltransferase activity. Moreover, CCND2 was identified as a putative target gene for SMYD3 transcriptional regulation, through trimethylation of H4K20.Our results support a proto-oncogenic role for SMYD3 in prostate carcinogenesis, mainly due to its methyltransferase enzymatic activity. Thus, SMYD3 overexpression is a potential biomarker for clinically aggressive disease and an attractive therapeutic target in PCa.

Overexpression of MCT1/4, CD147, GLUT1 and CAIX, supports previous findings of metabolic reprograming in OCC, warranting future studies to explore the hyper-glycolytic phenotype of these tumors. Importantly, MCT expression revealed to have a prognostic value in OCC survival.

Purpose Increased glycolytic activity with accumulation of extracellular lactate is regarded as a hallmark of cancer. In lymphomas, FDG-PET has undeniable diagnostic and prognostic value, corroborating that these tumours are avid for glucose. However, the role of glycolytic metabolism-related molecules in lymphoma is not well known. Here, we aimed to evaluate the clinical and prognostic significance of a panel of glycolytic metabolism-related molecules in primary non-Hodgkin lymphomas (NHL) and to test in vitro the putative therapeutic impact of lactate transport inhibition. Methods We assessed, by immunohistochemistry, the expression of the metabolism-related molecules MCT1, MCT2, MCT4, CD147, GLUT1, LDHA and CAIX in both tumour and stroma compartments of tissue sections obtained from 104 NHL patients. In addition, the lymphoma-derived cell lines OZ and DOHH-2 were used to evaluate the effect of AZD3965 on their viability and on apoptosis induction, as well as on extracellular lactate accumulation. Results We found that expression of MCT1 in the NHL tumour compartment was significantly associated with a poor clinicopathological profile. We also found that MCT4 and CAIX were present in the stromal compartment and correlated with an aggressive phenotype, while MCT1 was absent in this compartment. In addition, we found that AZD3965-mediated disruption of MCT1 activity led to inhibited NHL cell viability and extracellular lactate accumulation, while increasing apoptotic cell death.Conclusions Our results indicate that elevated glycolytic activity is associated with NHL aggressiveness, pointing at metabolic cooperation, mediated by MCT1 and MCT4, between tumour cells and their surrounding stroma. MCT1 may serve as a target to treat NHL (diffuse large B cell lymphoma) patients with high MCT1/low MCT4 expressing tumours. Further (pre-)clinical studies are required to allow the design of novel therapeutic strategies aimed at e.g. reprogramming the tumour microenvironment.