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Background and PurposeThe Na+/Ca2+ exchanger (NCX) working in either forward or reverse mode participates in maintaining intracellular Ca2+ ([Ca2+]i) homeostasis, which is essential for determining cell fate. Previously, numerous blockers targeting reverse or forward NCX have been developed and studied in ischaemic tissue injury but barely examined in glioblastoma for the purpose of anti‐tumour therapy. We assessed the effect of NCX blockers on glioblastoma growth and whether NCX can become a therapeutic target.Experimental ApproachPatch‐clamp recording, Ca2+ imaging, flow cytometry, and Western blot were used to study the effects of specific and non‐specific NCX blockers on cultured glioblastoma cells. In vivo bioluminescent imaging was used to measure effects on grafted glioblastoma.Key ResultsSelectively blocking the reverse NCX with SEA0400, SN‐6, and YM‐244769 did not affect tumour cell viability. Blocking the forward NCX with bepridil, CB‐DMB, or KB‐R7943 elevated [Ca2+]i and killed glioblastoma cells. Bepridil and CB‐DMB caused Ca2+‐dependent cell cycle arrest together with apoptosis, which were all attenuated by a Ca2+ chelator BAPTA‐AM. Systemic administration of bepridil inhibited growth of brain‐grafted glioblastoma. Bepridil did not appear to have a cytotoxic effect on human astrocytes, which have higher functional expression of NCX than glioblastoma cells.Conclusions and ImplicationsLow expression of the NCX makes glioblastoma cells sensitive to disturbance of [Ca2+]i. Interventions designed to block the forward NCX can cause Ca2+‐mediated injury to glioblastoma thus having therapeutic potential. Bepridil could be a lead compound for developing new anti‐tumour drugs.

The continuing demand for new optoelectronic devices drives researchers to seek new materials suitable for photodetector applications. Recently, ternary compound semiconductors have entered researchers’ field of vision, among which chalcohalides have attracted special interest because of their rich properties and unique crystal structure consisting of atom chains and inter-chain van der Waals gaps. We have synthesized high-quality BiSeI single crystals with [110]-plane orientation and fabricated a photodetector. The optoelectronic measurements show a pronounced photocurrent signal with outstanding technical parameters, namely high responsivity (3.2 A/W), specific detectivity (7 × 1010 Jones) and external quantum efficiency (622%) for λ = 635 nm, V ds = 0.1 V and P opt = 0.23 mW/cm2. The high performance of BiSeI photodetector and its layer structure make it a promising candidate for low-dimensional optoelectronic applications.