Pancreatic ductal adenocarcinoma (PDAC) is one of the most deadly cancers. PDAC is a solid tumour with a hypoxic environment where cancer cells are highly active, generate acidic metabolites and protons, creating an acidic tumour microenvironment (TME). Tumour acidosis is believed to be a key player in tumour progression, development, aggression, and chemoresistance. Despite being crucial to understanding the role of extracellular pH (pHe) in tumour progression, there are very few established tools in PDAC. Dysregulation of transporters/channels in the pancreas might play a crucial role in PDAC. We hypothesize that H+, K+ -ATPase might contribute to TME acidification and might have functional relation with pH-sensitive K2P channels in tumour progression and development. The first aim was to monitor pHe in the TME. The approach was to stably transfect PDAC cells with a pHe sensor to measure the pHe change. The second aim was to study the functional activities of H+, K+ -ATPase, and pH-sensitive K2P channels in PDAC and investigate whether these transporters/channels are targetable. The approach was to study the expression of transporters/channels in PDAC and target them with drugs to study functional implications. We generated PANC-1 cells stably transfected with a pHe sensor that can monitor pHe in monolayer culture and spheroids. On targeting of H+, K+ -ATPase with Pantoprazole increases pHe in our pHe sensor cells. Several PDAC cell lines were adapted to acidic media, and some were transferred back to pH 7.4 to imitate aggressive/metastatic cancer cells. Pantoprazole inhibited cell proliferation, presumably by inhibiting H+, K+ -ATPase, and this was higher in acid-adapted cells compared to pH 7.4 cells, apparent with upregulation of H+, K+ -ATPase. Several PDAC cell lines express pH-sensitive K2P channels (TREK-1, TREK-2, and TASK-2). The pH-sensitive K2P channels were targeted openers, Riluzole or BL 1240, which showed that both drugs hyperpolarize the membrane potential of PANC-1 cells, indicating K+ conductance presumably through TREK-1 and TREK-2 channels. We targeted H+, K+ -ATPase with Pantoprazole and pH-sensitive K2P channels with Riluzole and BL 1249. The data showed that Pantoprazole and Riluzole significantly reduced cell proliferation, spheroid growth, and spheroid viability alone but combined, had a significantly larger effect indicating synergism or additivity. In conclusion, this Ph.D. work provides insights into a novel simplified method for monitoring pHe in in vitro models and the significance of H+, K+ -ATPase, and pH-sensitive K2P channels in PDAC development. We speculate that co-targeting H+, K+ -ATPase, and pH-sensitive K2P channels could be novel therapeutic approaches for PDAC.