Kekoa Taparra

Dr. Kekoa Taparra

Department of Radiation Oncology, Stanford University, 875 Blake Wilbur Dr, Palo Alto, CA 94304, USA
orcid

Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
14 June 2017 in Cancer Research
Verified
Journal Article
Open access
PDF file
RMReem Malek
Reem Malek
RGRajendra P. Gajula
Rajendra P. Gajula
RWRussell D. Williams
Russell D. Williams
BNBelinda Nghiem
Belinda Nghiem
BSBrian W. Simons
Brian W. Simons
PTPhuoc Tran
Phuoc Tran
TWIST1 is a transcription factor critical for development that can promote prostate cancer metastasis. During embryonic development, TWIST1 and HOXA9 are coexpressed in mouse prostate and then silenced postnatally. Here we report that TWIST1 and HOXA9 coexpression are reactivated in mouse and human primary prostate tumors and are further enriched in human metastases, correlating with survival. TWIST1 formed a complex with WDR5 and the lncRNA Hottip/HOTTIP, members of the MLL/COMPASS–like H3K4 methylases, which regulate chromatin in the Hox/HOX cluster during development. TWIST1 overexpression led to coenrichment of TWIST1 and WDR5 as well as increased H3K4me3 chromatin at the Hoxa9/HOXA9 promoter, which was dependent on WDR5. Expression of WDR5 and Hottip/HOTTIP was also required for TWIST1-induced upregulation of HOXA9 and aggressive cellular phenotypes such as invasion and migration. Pharmacologic inhibition of HOXA9 prevented TWIST1-induced aggressive prostate cancer cellular phenotypes in vitro and metastasis in vivo. This study demonstrates a novel mechanism by which TWIST1 regulates chromatin and gene expression by cooperating with the COMPASS-like complex to increase H3K4 trimethylation at target gene promoters. Our findings highlight a TWIST1–HOXA9 embryonic prostate developmental program that is reactivated during prostate cancer metastasis and is therapeutically targetable. Cancer Res; 77(12); 3181–93. ©2017 AACR.

1 June 2021 in European Urology Oncology
Verified
Journal Article
Closed access
MDMatthew P. Deek
Matthew P. Deek
KTKekoa Taparra
Kekoa Taparra
RPRyan Phillips
Ryan Phillips
PVPedro Isaacsson Velho
Pedro Isaacsson Velho
RGRobert W. Gao
Robert W. Gao
BSBradley J. Stish
Bradley J. Stish

1 August 2022 in JCO Oncology Practice
Verified
Journal Article
Closed access
KTKekoa Taparra
Kekoa Taparra
EDEdward Christopher Dee
Edward Christopher Dee
DDDyda Dao
Dyda Dao
RPRohan Patel
Rohan Patel
PSPatricia Santos
Patricia Santos
FCFumiko Chino
Fumiko Chino
PURPOSE: Aggregation of Asian Americans (AAs) with Native Hawaiians and Other Pacific Islanders (NHPIs) masks significant health disparities. We evaluated overall survival (OS) and surgery-to-radiation intervals (STRIs) among AA and NHPI women with early-stage breast cancer. METHODS: This National Cancer Database study included women with stage 0-II breast cancer diagnosed between 2004 and 2017. STRI was defined as days from surgery to radiation. Patients were stratified by adjuvant treatment. AAs were disaggregated into geographically relevant subpopulations: East, South, and Southeast Asians. Kaplan-Meier estimates and log-rank tests assessed survival. Cox proportional hazard and linear regression were adjusted for clinical and sociodemographic factors. RESULTS: In total, 578,927 women were included (median age 61 years, median follow-up 65 months, and 10-year OS 83%). AA and NHPI 10-year OS was 91% overall; subpopulation 10-year OS was 92% for East Asian, 90% for South Asian, 90% for Southeast Asian, and 83% for NHPI. On multivariable analysis, compared with non-Hispanic White, NHPI women had worse survival (adjusted hazard ratio [aHR] = 1.38; 95% CI, 1.09 to 1.77); all AA subpopulations had improved survival: East Asian (aHR = 0.57; 95% CI, 0.48 to 0.69), South Asian (aHR = 0.66; 95% CI, 0.51 to 0.84), and Southeast Asian (aHR = 0.78; 95% CI, 0.65 to 0.94). The AA and NHPI median STRI for was 73 days overall; the disaggregated median STRI was 68 days for East Asian, 80 days for South Asian, 77 days for Southeast Asians, and 81 days for NHPI. On adjusted analysis, compared with non-Hispanic White, Southeast Asians and NHPI had longer STRI by 6.6 (95% CI, 4.3 to 8.9) and 10.0 (95% CI, 5.8 to 14) days, respectively. CONCLUSION: Breast cancer disparities exist among disaggregated AA and NHPI subpopulations. Data disaggregation insights may lead to interventions to overcome these disparities, such as optimizing time-to-treatment for select populations.

1 March 2021 in JCO Oncology Practice
Verified
Journal Article
Closed access
KTKekoa Taparra
Kekoa Taparra
RMRobert C. Miller
Robert C. Miller
CDCurtiland Deville
Curtiland Deville

1 January 2022 in JCO Oncology Practice
Verified
Journal Article
Closed access
BJBhav Jain
Bhav Jain
KNKenrick Ng
Kenrick Ng
PSPatricia Mae G. Santos
Patricia Mae G. Santos
KTKekoa Taparra
Kekoa Taparra
VMVinayak Muralidhar
Vinayak Muralidhar
EDEdward Christopher Dee
Edward Christopher Dee
PURPOSE: We identified (1) differences in localized prostate cancer (PCa) risk group at presentation and (2) disparities in access to initial treatment for Asian American, Native Hawaiian, and Pacific Islander (AANHPI) men with PCa after controlling for sociodemographic factors. METHODS: We assessed all patients in the National Cancer Database with localized PCa with low-, intermediate-, and high-risk disease who identified as Thai, White, Asian Indian, Chinese, Vietnamese, Korean, Japanese, Filipino, Hawaiian, Pacific Islander, Laotian, Pakistani, Kampuchean, and Hmong. Multivariable logistic regression defined adjusted odds ratios (AORs) with 95% CI of (1) presenting at progressively higher risk group and (2) receiving treatment or active surveillance with intermediate- or high-risk disease, adjusting for sociodemographic and clinical factors. RESULTS: Among 980,889 men (median age 66 years), all AANHPI subgroups with the exception of Thai (AOR = 0.84 [95% CI, 0.58 to 1.21], P > .05), Asian Indian (AOR = 1.12 [95% CI, 1.00 to 1.25], P > .05), and Pakistani (AOR = 1.34 [95% CI, 0.98 to 1.83], P > .05) men had greater odds of presenting at a progressively higher PCa risk group compared with White patients (Chinese AOR = 1.18 [95% CI, 1.11 to 1.25], P < .001; Japanese AOR = 1.36 [95% CI, 1.26 to 1.47], P < .001; Filipino AOR = 1.37 [95% CI, 1.29 to 1.46], P < .001; Korean AOR = 1.32 [95% CI, 1.18 to 1.48], P < .001; Vietnamese AOR = 1.20 [95% CI, 1.07 to 1.35], P = .002; Laotian AOR = 1.60 [95% CI, 1.08 to 2.36], P = .018; Hmong AOR = 4.07 [95% CI, 1.54 to 10.81], P = .005; Kampuchean AOR = 1.55 [95% CI, 1.03 to 2.34], P = .036; Asian Indian or Pakistani AOR = 1.15 [95% CI, 1.07 to 1.24], P < .001; Native Hawaiians AOR = 1.58 [95% CI, 1.38 to 1.80], P < .001; and Pacific Islanders AOR = 1.58 [95% CI, 1.37 to 1.82], P < .001). Additionally, Japanese Americans (AOR = 1.46 [95% CI, 1.09 to 1.97], P = .013) were more likely to receive treatment compared with White patients. CONCLUSION: Our findings suggest that there are differences in PCa risk group at presentation by race or ethnicity among Asian American, Native Hawaiian, and Pacific Islander subgroups and that there exist disparities in treatment patterns. Although AANHPI are often studied as a homogenous group, heterogeneity upon subgroup disaggregation underscores the importance of further study to assess and address barriers to PCa care.

18 April 2016 in Frontiers in Oncology
Verified
Journal Article
Open access
KTKekoa Taparra
Kekoa Taparra
PTPhuoc Tran
Phuoc Tran
NZNatasha Zachara
Natasha Zachara
The epithelial-mesenchymal transition (EMT) is a highly conserved program necessary for orchestrating distant cell migration during embryonic development. Multiple studies in cancer have demonstrated a critical role for EMT during the initial stages of tumorigenesis and later during tumor invasion. Transcription factors (TFs) such as SNAIL, TWIST, and ZEB are master EMT regulators that are aberrantly overexpressed in many malignancies. Recent evidence correlates EMT-related transcriptomic alterations with metabolic reprogramming in cancer. Metabolic alterations may allow cancer to adapt to environmental stressors, supporting the irregular macromolecular demand of rapid proliferation. One potential metabolic pathway of increasing importance is the hexosamine biosynthesis pathway (HBP). The HBP utilizes glycolytic intermediates to generate the metabolite UDP-GlcNAc. This and other charged nucleotide sugars serve as the basis for biosynthesis of glycoproteins and other glycoconjugates. Recent reports in the field of glycobiology have cultivated great curiosity within the cancer research community. However, specific mechanistic relationships between the HBP and fundamental pathways of cancer, such as EMT, have yet to be elucidated. Altered protein glycosylation downstream of the HBP is well positioned to mediate many cellular changes associated with EMT including cell-cell adhesion, responsiveness to growth factors, immune system evasion, and signal transduction programs. Here we outline some of the basics of the HBP and putative roles the HBP may have in driving EMT-related cancer processes. With novel appreciation of the HBP’s connection to EMT, we hope to illuminate the potential for new therapeutic targets of cancer.