Abstract
Human chorionic gonadotropin beta (hCG-β), while primarily recognized for its role in pregnancy, has also been implicated in poor prognosis for cancer patients over the past several decades. Targeting dysregulated hCG-β production by cancer cells may prove an effective way to combat tumor growth. We propose that targeting hCG-β production using antisense phosphorodiamidate morpholino oligomers (PMO) technology could provide a precise and effective strategy for lowering hCG-β levels. This method may offer enhanced specificity and the ability to modulate hCG-β expression directly at the mRNA transcript level. Here, we tested multiple PMO sequences targeted against hCG-β mRNA transcripts at various regions to ensure optimal sequence specificity and effective knockdown. We used cell viability assays, pregnancy test strips, and ELISA assays to determine knockdown by each PMO sequence to initially screen PMO sequences for identifying the most effective candidates. Of the sequences evaluated using ELISA, one demonstrated demonstrated effective knockdown at 0.5 µM and three at 1 µM. The remaining sequences required high PMO concentrations to observe a phenotype, and some did not produce measurable hCG knockdown under the conditions tested. Across nineteen PMO sequences tested in eight different cell lines, seven consistently reduced cell viability at 2-4 µM, whereas the remaining sequences showed variable or minimal effects. From the initial screen we identified the best PMO sequence, termed LK-1, for further analysis. We demonstrated that LK-1 is effective at significantly reducing hCG-β expression as measured both by western blot and ELISA assays. LK-1 treatment also showed significant reduction in cancer cell viability, reduce clonogenicity in colony formation assays, increased tumor cell death, and reduced invasion via wound healing assay in several cancer cell lines. We also showed that LK-1 is effective at reducing tumor formation in 3D spheroids. Combined, these findings suggest that targeting hCG-β production with morpholino-based therapy may represent a promising approach for cancers expressing this protein.
Data availability
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
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Acknowledgements
The authors would like to acknowledge and thank Morpholino Therapeutic employee, Dr. Eliseo Quiroz, for his support on several key projects. Dr. Jon Moulton, with his guidance on PMO designs provided through Gene Tools, LLC services. Dr. Stephen A. Butler and Donald E. Moss for their support and advice on certain aspects of the project.
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Morpholino Therapeutics, LLC funded the project. No other funding support was provided for this project.
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J. Helena Kinion designed and executed the experiments, analyzed the data, and wrote the manuscript. Brian P. Dolan contributed to experimental design, data analysis, and extensively revised the manuscript for publication. James E. Summerton helped with PMO designs and project funding. Michael McAllister performed key experiments, including western blots, scratch invasion assays, colony formation assays, and 3D tumor spheroid cultures.
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Authors Dr. Kinion and Dr. Summerton are the inventors in a patent related to the content of this manuscript. The other authors declare no competing interests.
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Kinion, J.H., McAllister, M.B., Summerton, J.E. et al. LK-1: an investigational therapy targeting hCG-β in metastatic breast, bladder, ovarian, and cervical cancers. Sci Rep (2026). https://doi.org/10.1038/s41598-026-38909-6
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DOI: https://doi.org/10.1038/s41598-026-38909-6
