Metabolic/hypoxial axis predicts tamoxifen resistance in breast cancer

Advanced breast cancer diagnosis: Multiplex RT-qPCR for precise typing and angiogenesis profiling

Breast cancer (BC) remains the foremost cause of cancer-related mortality, with an estimated 2.3 million new cases anticipated globally. The timely diagnosis of BC is pivotal for effective treatment. Currently, BC diagnosis predominantly relies on Immunohistochemistry (IHC), a method known for its sluggishness, expense, and dependence on proficient pathologists for confident cancer typing. In this study, we introduce a novel approach to enhance the accuracy, speed, and cost-effectiveness of BC diagnosis. We employ multiplex Reverse Transcription quantitative Polymerase Chain Reaction (RT-qPCR) with touch-down methods, which consistently yield significantly lower Cycle Threshold (CT) values. The study evaluates gene expression profiles of HER2, PGR, ESR, and Ki67 genes across 61 samples representing four BC subtypes, using RPL13A as the endogenous control gene. The results demonstrate that our method offers remarkable precision, nearly equivalent to IHC, in detecting gene expressions vital for BC diagnosis and subtyping. Moreover, we explore the gene expression of Hif1A, ANG, and VEGFR genes involved in angiogenesis, shedding light on the metastatic potential of the tested BC tumours. Notably, numerous samples exhibit elevated levels of Hif1A and VEGFR, indicating their potential as valuable biomarkers for assessing metastatic status. Collectively, our RT-qPCR methodology emerges as a powerful diagnostic tool for swiftly identifying BC subtypes and can be complemented with other essential tumorigenic biomarker assessments, such as angiogenesis, to further refine cancer characterisation and inform personalised therapeutic strategies for BC patients. This innovation holds the promise of revolutionising BC diagnosis and treatment, offering expedited and reliable insights for improved patient care.

The role of mitochondrial/metabolic axis in development of tamoxifen resistance in breast cancer

Only a few investigations, to our knowledge, have examined the bioenergetics of Tamoxifen (TMX) resistant individuals and reported altered mitochondrial activity and metabolic profile. The primary cause of TMX resistance is firmly suggested to be metabolic changes. Metabolic variations and hypoxia have also been linked in a bidirectional manner. Increased hypoxic levels correlate with early recurrence and proliferation and have a negative therapeutic impact on breast cancer (BC) patients. Hypoxia, carcinogenesis, and patient death are all correlated, resulting in more aggressive traits, a higher chance of metastasis, and TMX resistance. Consequently, we sought to investigate the possible role of the metabolic/hypoxial axis Long non-coding RNA (LncRNA) Taurine up-regulated 1 (TUG-1), Micro-RNA 186-5p (miR-186), Sirtuin-3 (SIRT3), Peroxisome Proliferator Activator Receptor alpha (PPAR-α), and Hypoxia-Inducible Factor-1 (HIF-1) in the development of TMX resistance in BC patients and to correlate this axis with tumor progression. Interestingly, this will be the first time to explore epigenetic regulation of this axis in BC.