Publications by authors named "Kristina Havas"

Targeting aromatase deprives ER breast cancers of estrogens and is an effective therapeutic approach for these tumors. However, drug resistance is an unmet clinical need. Lipidomic analysis of long-term estrogen-deprived (LTED) ER breast cancer cells, a model of aromatase inhibitor resistance, revealed enhanced intracellular lipid storage.

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Cancers feature substantial intratumoral heterogeneity of genetic and phenotypically distinct lineages. Although interactions between coexisting lineages are emerging as a potential contributor to tumor evolution, the extent and nature of these interactions remain largely unknown. We postulated that tumors develop ecological interactions that sustain diversity and facilitate metastasis.

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Next-generation Trop-2-targeted therapy against advanced cancers is hampered by expression of Trop-2 in normal tissues. We discovered that Trop-2 undergoes proteolytic activation by ADAM10 in cancer cells, leading to the exposure of a previously inaccessible protein groove flanked by two N-glycosylation sites. We designed a recognition strategy for this region, to drive selective cancer vulnerability in patients.

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The process in which locally confined epithelial malignancies progressively evolve into invasive cancers is often promoted by unjamming, a phase transition from a solid-like to a liquid-like state, which occurs in various tissues. Whether this tissue-level mechanical transition impacts phenotypes during carcinoma progression remains unclear. Here we report that the large fluctuations in cell density that accompany unjamming result in repeated mechanical deformations of cells and nuclei.

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Circulating tumor cell (CTC) clusters are associated with increased metastatic potential and worse patient prognosis, but are rare, difficult to count, and poorly characterized biophysically. The PillarX device described here is a bimodular microfluidic device (Pillar-device and an X-magnetic device) to profile single CTCs and clusters from whole blood based on their size, deformability, and epithelial marker expression. Larger, less deformable clusters and large single cells are captured in the Pillar-device and sorted according to pillar gap sizes.

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Trop-2 is a transmembrane signal transducer that is overexpressed in most human cancers, and drives malignant progression. To gain knowledge on the higher-order molecular mechanisms that drive Trop-2 signaling, we applied next-generation sequencing, proteomics, and high-resolution microscopy to models and primary cases of human colorectal cancer (CRC). We had previously shown that Trop-2 induces a Ca signal.

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ATR responds to mechanical stress at the nuclear envelope and mediates envelope-associated repair of aberrant topological DNA states. By combining microscopy, electron microscopic analysis, biophysical and in vivo models, we report that ATR-defective cells exhibit altered nuclear plasticity and YAP delocalization. When subjected to mechanical stress or undergoing interstitial migration, ATR-defective nuclei collapse accumulating nuclear envelope ruptures and perinuclear cGAS, which indicate loss of nuclear envelope integrity, and aberrant perinuclear chromatin status.

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Tumor recurrence is now the leading cause of breast cancer-related death. These recurrences are believed to arise from residual cancer stem cells that survive initial therapeutic intervention. Therefore, a comprehensive understanding of cancer stem cell biology is needed to generate more effective therapies.

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Tumor recurrence is the leading cause of breast cancer-related death. Recurrences are largely driven by cancer cells that survive therapeutic intervention. This poorly understood population is referred to as minimal residual disease.

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Background: DNA vaccines provide high tolerability and safety but commonly suffer from suboptimal immunogenicity. We previously reported that a plasmid vector (pATRex), encoding the DNA sequence for the von Willebrand I/A domain of the tumor endothelial marker-8 (TEM8) when given in combination with plasmid-encoded tumor antigens acted as a powerful molecular adjuvant enhancing immunity against breast and melanoma tumors.

Aims: In the present study we addressed two unsolved issues; would the adjuvant action of pATRex extend to a DNA vaccine against infectious disease and, if so, what is the mechanistic basis for pATRex adjuvant action?

Results: Here we show in a murine malaria vaccine model that co-administration of pATRex potentiates antibody production elicited by an intramuscular injection of plasmid encoding Plasmodium yoelii merozoite surface protein 4/5 (PyMSP4/5).

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Regulation of the Saccharomyces cerevisiae HO promoter has been shown to require the recruitment of chromatin-modifying and -remodeling enzymes. Despite this, relatively little is known about what changes to chromatin structure occur during the course of regulation at HO. Here, we used indirect end labeling in synchronized cultures to show that the chromatin structure is disrupted in a region that spans bp -600 to -1800 relative to the transcriptional start site.

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Nuclear receptors, including the androgen receptor (AR), regulate target cell transcription through interaction with auxiliary proteins to modify chromatin structure. We describe herein a novel AR-interacting protein, termed ARIP4, that has structural features typical of the SNF2-like protein family. With regard to the Snf2 domain, the closest homolog of ARIP4 is the ATRX protein.

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