Rice, Robert - Research

Areas of Interest

Mechanism of arsenic carcinogenicity. We have been tracing important signaling pathways with which inorganic arsenic interferes, thereby preserving the germinative capability of keratinocytes. This includes markedly prolonging EGF receptor activity, preventing its suppression by insulin/IGF action. Arsenite also suppresses Notch-1 activation, protein kinase Cδ expression and dual specificity phosphatase induction, all of which inhibit cells from leaving the mitotic pool and thus inhibit differentiation. These findings help rationalize the contribution of inorganic arsenic in the water supply to cancer development. We have found that antimonite mimics arsenite remarkably well, suggesting it also targets the epidermis.

  • Patterson TJ, Reznikova TV, Phillips MA, Rice RH (2005) Arsenic maintains germinative state in cultured human epidermal cells. Toxicol Appl Pharmacol 207:69-77. doi: 10.1016/j.taap.2004.11.020
  • Reznikova TV, Phillips MA, Patterson TJ, Rice RH (2010) Opposing actions of insulin and arsenite converge on PKCδ to alter keratinocyte proliferative potential and differentiation. Molec Carcinogenesis 49:398-409. doi: 10.1002/mc.20612
  • Phillips MA, Qin Q, Hu Q, Zhao B, Rice RH (2013) Arsenite suppression of BMP signaling in human keratinocytes. Toxicol Appl Pharmacol 269:290-296. doi: 10.1016/j.taap.2013.02.017
  • Phillips MA, Cánovas A, Wu P-W, Islas-Trejo A, Medrano JF, Rice RH (2016) Parallel responses of human epidermal keratinocytes to inorganic SbIII and AsIII. Environ Chem 13:963-970. doi: 10.1071/EN16019
  • Phillips MA, Cánovas A, Rea MA, Islas-Trejo A, Medrano JF, Durbin-Johnson B, Rocke DM, Rice RH (2020) Deducing signaling pathways from parallel actions of arsenite and antimonite in human epidermal keratinocytes. Sci Rep 10:2890. doi: 10.1038/s41598-020-59577-0

Development of keratinocyte culture models to study toxic exposures. We initially found that epithelial cells from a variety of rat tissues could be serially cultured and routinely developed into continuous lines. Then we derived a spontaneously immortalized keratinocyte line from ostensibly normal human epidermis and have used it as a minimally-deviated complement to normal human epidermal cells for studies of differentiation and response to carcinogens such as arsenic, benzo(a)pyrene and 2,3,7,8-tetrachlorodibenzo-p-dioxin. We have now developed a method to serially culture keratinocyte-like epithelial cells from fish as toxic target models.

  • Phillips MA, Rice RH (1983) Convergent differentiation in cultured rat cells from nonkeratinized epithelia: Keratinocyte character and intrinsic differences. J Cell Biol 97:686-691. doi: 10.1083/jcb.97.3.686
  • Walsh AA, deGraffenried LA, Rice RH (1995) 2,3,7,8-Tetrachlorodibenzo-p-dioxin sensitization of cultured human epidermal cells to toxicity from a carcinogenic heterocyclic amine. Carcinogenesis 16:2187-2191. doi: 10.1093/carcin/16.9.2187
  • Hu Q, Rice RH, Qin Q, Phinney BS, Eigenheer RA, Bao W, Zhao B (2013) Proteomic analysis of human keratinocyte response to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure. J Proteome Res 12:5340-5347. doi: 10.1021/pr4006266
  • Lin L-W, Denison MS, Rice RH (2021) Woodsmoke extracts cross-link proteins and induce cornified envelope formation without stimulating keratinocyte terminal differentiation. Toxicol Sci 183:128-138. doi: 10.1093/toxsci/kfab071
  • Karim N, Lin L-W, Van Eenennaam JP, Fangue NA, Schreier AD, Phillips MA, Rice RH (2022) Epidermal cell cultures from white and green sturgeon (Acipenser transmontanus and medirostris): expression of TGM1-like transglutaminases and CYP4501A. PLoS One 17(3):e0265218. doi: 10.1371/journal.pone.0265218

Proteomic profiling of corneocytes and manifestation of genetic defects. We have applied mass spectrometry-based proteomics to the difficult problem of identifying proteins containing isopeptide cross-links in structures composed of mature keratinocytes. We presented the first cross-linked proteomes of hair shaft, nail plate and epidermal callus. We have shown this approach can be applied to humans and to animal models of disease (mouse epidermis, nail, hair). This is useful to understand the downstream phenotypic consequences of damage even to a single gene and is projected to permit more quantitative monitoring of skin disease after therapeutic treatment. We have explored applications to characterizing effects of environmental exposures (arsenic, TCDD) and to study effects of air pollutants such as starting wood smoke on human epidermis.

  • Rice RH, Durbin-Johnson BP, Ishitsuka YI, Salemi M, Phinney BS, Rocke DM, Roop DR (2016) Proteomic analysis of loricrin knockout mouse epidermis. J Proteome Res 15:2560-2566. doi: 10.1021/acs.jproteome.6b00108
  • Wu P-W, Mason KE, Durbin-Johnson BP, Salemi M, Phinney BS, Rocke DM, Parker GJ, Rice RH (2017) Proteomic analysis of hair shafts from monozygotic twins: Expression profiles and genetically variant peptides. Proteomics 17:13–14, 1600462. doi: 10.1002/pmic.201600462
  • Rice RH, Durbin-Johnson BP, Mann SM, Salemi M, Urayama S, Rocke DM, Phinney BS, Sundberg JP (2018) Corneocyte proteomics: Applications to skin biology and dermatology. Exp Dermatol 27(8):931-938. doi: 10.1111/exd.13756
  • Karim N, Durbin-Johnson B, Rocke DM, Salemi M, Phinney BS, Naeem M, Rice RH (2019) Proteomic manifestations of genetic defects in autosomal recessive congenital ichthyosis. J Proteomics 201:104-109. doi: 10.1016/j.jprot.2019.04.007
  • Karim N, Mirmirani P, Durbin-Johnson BP, Rocke DM, Salemi M, Phinney BS, Rice RH (2023). Protein profiling of forehead and scalp epidermal corneocytes distinguishes frontal fibrosing from androgenetic alopecia. PLoS One 18(3):e0283619. doi: 10.1371/journal.pone.0283619

Role of keratinocyte transglutaminase (TGM1). We showed that cross-linked envelopes in mature corneocytes consist of isopeptide cross-linked protein containing a previously unknown protein, involucrin. We also molecularly cloned the TGM1 transglutaminase enzyme responsible for cross-linking with other proteins and discovered it is membrane-bound by virtue of a cluster of cysteine residues near the amino terminus that become thioesterified with palmitate. The monoclonal antibody we raised to the human enzyme helped identify defects in the TGM1 gene as the most common cause of lamellar ichthyosis. Our cDNA for the full length coding region demonstrated that its expression in ichthyosis keratinocytes could repair the defect. We have now shown that TGM1 in teleosts is membrane-bound, suggesting it was re-purposed during evolution to permit adaptation to the terrestrial environment.

  • Rice RH, Green H (1979) Presence in human epidermal cells of a soluble protein precursor of the cross-linked envelope: Activation of the cross-linking process by calcium ions. Cell 18:681-694. doi: 10.1016/0092-8674(79)90123-5
  • Thacher SM, Rice RH (1985) Keratinocyte-specific transglutaminase of cultured human epidermal cells: Relation to cross-linked envelope formation and terminal differentiation. Cell 40:685-695. doi: 10.1016/0092-8674(85)90217-x
  • Phillips MA, Stewart BE, Rice RH (1992) Genomic structure of keratinocyte transglutaminase. Recruitment of new exon for modified function. J Biol Chem 267:2282-2286. doi: 10.1016/S0021-9258(18)45875-9
  • Phillips MA, Qin Q, Mehrpouyan M, Rice RH (1993) Keratinocyte transglutaminase membrane anchorage: Analysis of site-directed mutants. Biochemistry 32:11057-11063. doi: 10.1021/bi00092a015
  • Rodriguez Cruz SI, Phillips MA, Kültz D, Rice RH (2017) Tgm1-like transglutaminases in Tilapia (Oreochromis mossambicus). PLoS One 12(5):e0177016. doi: 10.1371/journal.pone.0177016

Complete List of Published Work in PubMed (150 entries):
https://www.ncbi.nlm.nih.gov/pubmed/?term=rice+rh

Links to Publications Supplementary Information:
Global alteration of gene expression in human keratinocytes by inorganic arsenic
Parallel responses of human epidermal keratinocytes to inorganic SbIII and AsIIl
Table S1. Proteomic results
Table S2. Results of next generation sequencing