Publications

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  • Loss of Primary Cilia Drives Switching from Hedgehog to Ras/MAPK Pathway in Resistant Basal Cell Carcinoma JOURNAL OF INVESTIGATIVE DERMATOLOGY Kuonen, F., Huskey, N. E., Shankar, G., Jaju, P., Whitson, R. J., Rieger, K. E., Atwood, S. X., Sarin, K. Y., Oro, A. E. 2019; 139 (7): 1439?48
  • Loss of primary cilia drives switching from Hedgehog to Ras/MAPK pathway in resistant basal cell carcinoma. The Journal of investigative dermatology Kuonen, F., Huskey, N. E., Shankar, G., Jaju, P., Whitson, R. J., Rieger, K. E., Atwood, S. X., Sarin, K. Y., Oro, A. E. 2019

    Abstract

    Basal cell carcinomas (BCCs) rely on Hedgehog (HH) pathway growth signal amplification by the microtubule-based organelle, the primary cilium. Despite naive tumors responsiveness to Smoothened inhibitors (Smoi), resistance in advanced tumors remains frequent. While the resistant BCCs usually maintain HH pathway activation, squamous cell carcinomas with Ras/MAPK pathway activation also arise, with the molecular basis of tumor type and pathway selection still obscure. Here we identify the primary cilium as a critical determinant controlling tumor pathway switching. Strikingly, Smoi-resistant BCCs possess an increased mutational load in ciliome genes, resulting in reduced primary cilia and HH pathway activation compared to naive or Gorlin patient BCCs. Gene set enrichment analysis of resistant BCCs with a low HH pathway signature reveals increased Ras/MAPK pathway activation. Tissue analysis confirms an inverse relationship between primary cilia presence and Ras/MAPK activation, and primary cilia removal in BCCs potentiates Ras/MAPK pathway activation. Moreover, activating Ras in HH-responsive cell lines confers resistance to both canonical (vismodegib) and non-canonical (aPKC and MRTF inhibitors) HH pathway inhibitors, while conferring sensitivity to MAPK inhibitors. Our results provide insights into BCC treatment and identify the primary cilium as an important lineage gatekeeper, preventing HH to Ras/MAPK pathway switching.

    View details for PubMedID 30707899

  • Factors influencing and modifying the decision to pursue genetic testing for skin cancer risk. Journal of the American Academy of Dermatology Fogel, A. L., Jaju, P. D., Li, S., Halpern-Felsher, B., Tang, J. Y., Sarin, K. Y. 2017

    Abstract

    Across cancers, the decision to pursue genetic testing is influenced more by subjective than objective factors. However, skin cancer, which is more prevalent, visual, and multifactorial than many other malignancies, may offer different motivations for pursuing such testing.The primary objective was to determine factors influencing the decision to receive genetic testing for skin cancer risk. A secondary objective was to assess the impact of priming with health questions on the decision to receive testing.We distributed anonymous online surveys through ResearchMatch.org to assess participant health, demographics, motivations, and interest in pursuing genetic testing for skin cancer risk. Two surveys with identical questions but different question ordering were used to assess the secondary objective.We received 3783 responses (64% response rate), and 85.8% desired testing. Subjective factors, including curiosity, perceptions of skin cancer, and anxiety, were the most statistically significant determinants of the decision to pursue testing (P < .001), followed by history of sun exposure (odds ratio 1.85, P < .01) and history of skin cancer (odds ratio 0.5, P = .01). Age and family history of skin cancer did not influence this decision. Participants increasingly chose testing if first queried about health behaviors (P < .0001).The decision to pursue hypothetical testing may differ from in-clinic decision-making. Self-selected, online participants may differ from the general population. Surveys may be subject to response bias.The decision to pursue genetic testing for skin cancer is primarily determined by subjective factors, such as anxiety and curiosity. Health factors, including skin cancer history, also influenced decision-making. Priming with consideration of objective health factors can increase the desire to pursue testing.

    View details for DOI 10.1016/j.jaad.2016.11.050

    View details for PubMedID 28087134

  • Genomic Stability in Syndromic Basal Cell Carcinoma. The Journal of investigative dermatology Chiang, A., Jaju, P. D., Batra, P., Rezaee, M., Epstein, E. H., Tang, J. Y., Sarin, K. Y. 2017

    Abstract

    Basal cell cancers (BCCs) are characterized by up-regulation of Hedgehog pathway through loss of Patched1 or activation of Smoothened, and smoothened-inhibitors such as vismodegib are effective therapies for advanced BCCs. Although most BCCs are sporadic, rare individuals with Basal Cell Nevus Syndrome (BCNS) harbor germline defects in Patched1 and develop up to hundreds of tumors that are histopathologically indistinguishable from sporadic BCCs. Interestingly, BCNS-BCCs are more responsive to Smoothened-inhibitors than sporadic BCCs, with minimal development of resistance. Given differences in clinical course and therapy response, we sought to characterize BCCs in the setting of BCNS. We found that BCNS individuals with low-tumor burden demonstrated significantly fewer UV signature somatic mutations and lower overall somatic mutational load compared to BCNS individuals with high-burden, supporting a role of UV exposure in driving BCC development in BCNS individuals. However, compared with sporadic BCCs, BCNS-BCCs have a significantly lower mutational load, lower proportion of ultraviolet mutagenesis, increased genomic stability, and harbor fewer functionally resistant Smoothened mutations at baseline, explaining why BCNS-BCCs lack intrinsic resistance to Smoothened-inhibitors. BCNS-BCCs appear to have reduced mutator phenotype as compared with sporadic BCCs, which may contribute to their relatively more indolent clinical course and responsiveness to therapy.

    View details for PubMedID 29111235

  • Invasive Melanoma in a Patient with Congenital Ichthyosiform Erythroderma PEDIATRIC DERMATOLOGY Jaju, P., Novoa, R. A., Swetter, S. M., Sarin, K. Y. 2017; 34 (1): E35-E36

    Abstract

    We describe the case of a 26-year-old woman with a history of congenital ichthyosiform erythroderma (CIE) who initially presented with a stage IIA amelanotic melanoma on her forearm that was surgically excised. We also review the literature on CIE-associated skin cancers and discuss the possible contribution of ichthyosis to the risk of cutaneous malignancies. Our findings emphasize the importance of close lifelong skin cancer screening in individuals with CIE and highlight the unique malignancy risk of these individuals.

    View details for DOI 10.1111/pde.13012

    View details for Web of Science ID 000393955600008

  • Invasive Melanoma in a Patient with Congenital Ichthyosiform Erythroderma. Pediatric dermatology Jaju, P., Novoa, R. A., Swetter, S. M., Sarin, K. Y. 2016

    Abstract

    We describe the case of a 26-year-old woman with a history of congenital ichthyosiform erythroderma (CIE) who initially presented with a stage IIA amelanotic melanoma on her forearm that was surgically excised. We also review the literature on CIE-associated skin cancers and discuss the possible contribution of ichthyosis to the risk of cutaneous malignancies. Our findings emphasize the importance of close lifelong skin cancer screening in individuals with CIE and highlight the unique malignancy risk of these individuals.

    View details for DOI 10.1111/pde.13012

    View details for PubMedID 27813222

  • Familial skin cancer syndromes Increased risk of nonmelanotic skin cancers and extracutaneous tumors JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY Jaju, P. D., Ransohoff, K. J., Tang, J. Y., Sarin, K. Y. 2016; 74 (3): 437-451

    Abstract

    Nonmelanoma skin cancers (NMSCs) represent the most common malignancies worldwide, with reported incidence rising each year. Both cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), as well as other NMSCs, represent complex diseases with a combination of environmental and genetic risk factors. In general, hereditary cancer syndromes that increase the risk of NMSC fall under several broad categories: those associated with immunodeficiencies, those that affect skin pigmentation, and those that perturb key molecular pathways involved in the pathogenesis of NMSCs. Many of the syndromes are also associated with extracutaneous manifestations, including internal malignancies; therefore, most require a multidisciplinary management approach with a medical geneticist. Finally, dermatologists play a critical role in the diagnosis and management of these conditions, because cutaneous findings are often the presenting manifestations of disease.

    View details for DOI 10.1016/j.jaad.2015.08.073

    View details for Web of Science ID 000370372300008

    View details for PubMedID 26892653

  • Familial skin cancer syndromes Increased melanoma risk JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY Ransohoff, K. J., Jaju, P. D., Tang, J. Y., Carbone, M., Leachman, S., Sarin, K. Y. 2016; 74 (3): 423-434

    Abstract

    Phenotypic traits, such as red hair and freckling, increase melanoma risk by 2- to 3-fold. In addition, approximately 10% of melanomas are caused by inherited germline mutations that increase melanoma risk from 4- to >1000-fold. This review highlights the key genes responsible for inherited melanoma, with an emphasis on when a patient should undergo genetic testing. Many genetic syndromes associated with increased melanoma risk are also associated with an increased risk of other cancers. Identification of these high-risk patients is essential for preventive behavior reinforcement, genetic counseling, and ensuring other required cancer screenings.

    View details for DOI 10.1016/j.jaad.2015.09.070

    View details for PubMedID 26892652

  • Mutations in the Kinetochore Gene KNSTRN in Basal Cell Carcinoma. journal of investigative dermatology Jaju, P. D., Nguyen, C. B., Mah, A. M., Atwood, S. X., Li, J., Zia, A., Chang, A. L., Oro, A. E., Tang, J. Y., Lee, C. S., Sarin, K. Y. 2015; 135 (12): 3197-3200

    View details for DOI 10.1038/jid.2015.339

    View details for PubMedID 26348826

  • Monoclonal antibodies (mAbs) to myelin proteolipid protein (PLP) epitopes recognize neurons in the developing human CNS 83rd Annual Meeting of the American-Association-of-Neuropathologists Sobel, R. A., Jaju, P., Eaton, M. J., Hinojoza, J. R. LIPPINCOTT WILLIAMS & WILKINS. 2007: 431?31
  • Monoclonal antibodies (mAbs) to myelin proteolipid protein (PLP) epitopes recognize neurons in the developing human CNS Experimental Biology 2007 Annual Meeting Sobel, R. A., Jaju, P., Eaton, M. J., Hinojoza, J. R. FEDERATION AMER SOC EXP BIOL. 2007: A64?A65

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