1
|
Kumar S, Talluri S, Zhao J, Liao C, Potluri LB, Buon L, Mu S, Shi J, Chakraborty C, Tai YT, Samur MK, Munshi NC, Shammas MA. ABL1 kinase plays an important role in spontaneous and chemotherapy-induced genomic instability in multiple myeloma. Blood 2024; 143:996-1005. [PMID: 37992230 DOI: 10.1182/blood.2023021225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 11/02/2023] [Accepted: 11/03/2023] [Indexed: 11/24/2023] Open
Abstract
ABSTRACT Genomic instability contributes to cancer progression and is at least partly due to dysregulated homologous recombination (HR). Here, we show that an elevated level of ABL1 kinase overactivates the HR pathway and causes genomic instability in multiple myeloma (MM) cells. Inhibiting ABL1 with either short hairpin RNA or a pharmacological inhibitor (nilotinib) inhibits HR activity, reduces genomic instability, and slows MM cell growth. Moreover, inhibiting ABL1 reduces the HR activity and genomic instability caused by melphalan, a chemotherapeutic agent used in MM treatment, and increases melphalan's efficacy and cytotoxicity in vivo in a subcutaneous tumor model. In these tumors, nilotinib inhibits endogenous as well as melphalan-induced HR activity. These data demonstrate that inhibiting ABL1 using the clinically approved drug nilotinib reduces MM cell growth, reduces genomic instability in live cell fraction, increases the cytotoxicity of melphalan (and similar chemotherapeutic agents), and can potentially prevent or delay progression in patients with MM.
Collapse
Affiliation(s)
- Subodh Kumar
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| | - Srikanth Talluri
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| | - Jiangning Zhao
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| | - Chengcheng Liao
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| | - Lakshmi B Potluri
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| | - Leutz Buon
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Shidai Mu
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| | - Jialan Shi
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
- Department of Medicine, Harvard Medical School, Boston, MA
| | - Chandraditya Chakraborty
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Yu-Tzu Tai
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Mehmet K Samur
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Nikhil C Munshi
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
- Department of Medicine, Harvard Medical School, Boston, MA
| | - Masood A Shammas
- The Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| |
Collapse
|
2
|
Prabhala R, Pierceall WE, Samur M, Potluri LB, Hong K, Peluso T, Talluri S, Wang A, Katiki A, Vangala SD, Buonopane M, Bade V, Seah H, Krogman A, Derebail S, Fulciniti M, Lazo SB, Richardson P, Anderson K, Corre J, Avet-Loiseau H, Thakurta A, Munshi N. Immunomodulation of NK, NKT and B/T cell subtypes in relapsed/refractory multiple myeloma patients treated with pomalidomide along with velcade and dexamethasone and its association with improved progression-free survival. Front Oncol 2023; 13:1271807. [PMID: 38111533 PMCID: PMC10726115 DOI: 10.3389/fonc.2023.1271807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 11/08/2023] [Indexed: 12/20/2023] Open
Abstract
Background Multiple Myeloma (MM) patients exhibit dysregulated immune system, which is further weakened by chemotherapeutic agents. While cereblon-modulating agents, such as pomalidomide and lenalidomide, have been found to improve the immune profile, the efficacy of their impact in combination with other treatments is yet unknown. Methods We conducted an immune-profiling of a longitudinal cohort of 366 peripheral blood samples from the CC4047-MM-007 (OPTIMISMM, NCT01734928) study. This study followed relapsed/refractory Multiple Myeloma (RRMM) patients who were treated with Velcade + dexamethasone (Vd), or Vd with pomalidomide (PVd). 366 blood samples from 186 patients were evaluated using multi-color flow cytometry at 3 timepoints: screening, day 8 of cycle 1, and cycle 3. Results Among NK and NKT cell populations, adding pomalidomide showed no inhibition in the frequency of NK cells. When expression of double positivity for activation markers like, p46/NKG2D, on NK cells was higher than the median, PVd treated patients showed significantly better (p=0.05) progression-free survival (PFS) (additional 15 months) than patients with lower than the median expression of p46/NKG2D on NK cells. PVd treated patients who expressed CD158a/b below the median at cycle 1 demonstrated a significantly better PFS (more than 18months). Among B cell subtypes, PVd treatment significantly increased the abundance of B1b cells (p<0.05) and decreased Bregs (p<0.05) at day 8 of both cycle 1 and cycle 3 when compared to screening samples. Of all the B cell-markers evaluated among paired samples, a higher expression of MZB cells at day 8 of cycle 1 has resulted in enhanced PFS in PVd treated patients. Within T cells, pomalidomide treatment did not decrease the frequency of CD8 T cells when compared with screening samples. The higher the surface expression of OX-40 on CD8 T cells and the lower the expression of PD-1 and CD25 on CD4 T cells by PVd treatment resulted in improved PFS. Conclusion The prognostic significance for the number of immune markers is only seen in the PVd arm and none of these immune markers exhibit prognostic values in the Vd arm. This study demonstrates the importance of the immunomodulatory effects and the therapeutic benefit of adding pomalidomide to Vd treatment.
Collapse
Affiliation(s)
- Rao Prabhala
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
- VA Boston Healthcare System, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
| | | | - Mehmet Samur
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
- Department of Biostatistics, Harvard TH Chan School of Public Health, Boston, MA, United States
| | - Lakshmi B. Potluri
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Kevin Hong
- Bristol Myers Squibb, Summit, NJ, United States
| | | | - Srikanth Talluri
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Angela Wang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Aishwarya Katiki
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Sahan D. Vangala
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Michael Buonopane
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Vaishnavi Bade
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Hannah Seah
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Arthur Krogman
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Sanika Derebail
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Mariateresa Fulciniti
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Suzan B. Lazo
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Paul Richardson
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
| | - Kenneth Anderson
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
| | - Jill Corre
- Institut Universitaire du Cancer de Toulouse-Oncopole, Toulouse, France
| | | | - Anjan Thakurta
- Bristol Myers Squibb, Summit, NJ, United States
- Oxford Centre for Translational Myeloma Research, Oxford, United Kingdom
| | - Nikhil Munshi
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, United States
- VA Boston Healthcare System, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
| |
Collapse
|
3
|
Kumar S, Zhao J, Talluri S, Buon L, Mu S, Potluri LB, Liao C, Shi J, Chakraborty C, Gonzalez GB, Tai YT, Patel J, Pal J, Mashimo H, Samur MK, Munshi NC, Shammas MA. Elevated APE1 Dysregulates Homologous Recombination and Cell Cycle Driving Genomic Evolution, Tumorigenesis, and Chemoresistance in Esophageal Adenocarcinoma. Gastroenterology 2023; 165:357-373. [PMID: 37178737 PMCID: PMC10524563 DOI: 10.1053/j.gastro.2023.04.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 03/17/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023]
Abstract
BACKGROUND & AIMS The purpose of this study was to identify drivers of genomic evolution in esophageal adenocarcinoma (EAC) and other solid tumors. METHODS An integrated genomics strategy was used to identify deoxyribonucleases correlating with genomic instability (as assessed from total copy number events in each patient) in 6 cancers. Apurinic/apyrimidinic nuclease 1 (APE1), identified as the top gene in functional screens, was either suppressed in cancer cell lines or overexpressed in normal esophageal cells and the impact on genome stability and growth was monitored in vitro and in vivo. The impact on DNA and chromosomal instability was monitored using multiple approaches, including investigation of micronuclei, acquisition of single nucleotide polymorphisms, whole genome sequencing, and/or multicolor fluorescence in situ hybridization. RESULTS Expression of 4 deoxyribonucleases correlated with genomic instability in 6 human cancers. Functional screens of these genes identified APE1 as the top candidate for further evaluation. APE1 suppression in EAC, breast, lung, and prostate cancer cell lines caused cell cycle arrest; impaired growth and increased cytotoxicity of cisplatin in all cell lines and types and in a mouse model of EAC; and inhibition of homologous recombination and spontaneous and chemotherapy-induced genomic instability. APE1 overexpression in normal cells caused a massive chromosomal instability, leading to their oncogenic transformation. Evaluation of these cells by means of whole genome sequencing demonstrated the acquisition of changes throughout the genome and identified homologous recombination as the top mutational process. CONCLUSIONS Elevated APE1 dysregulates homologous recombination and cell cycle, contributing to genomic instability, tumorigenesis, and chemoresistance, and its inhibitors have the potential to target these processes in EAC and possibly other cancers.
Collapse
Affiliation(s)
- Subodh Kumar
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts
| | - Jiangning Zhao
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts
| | - Srikanth Talluri
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts
| | - Leutz Buon
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts
| | - Shidai Mu
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts
| | - Lakshmi B Potluri
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts
| | - Chengcheng Liao
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts
| | - Jialan Shi
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts; Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | | | - Gabriel B Gonzalez
- Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts; Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Yu-Tzu Tai
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts
| | - Jaymin Patel
- Department of Medicine, Harvard Medical School, Boston, Massachusetts; Hematology and Oncology, Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Jagannath Pal
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Pt. Jawahar Lal Nehru Memorial Medical College, Raipur, Chhattisgarh, India
| | - Hiroshi Mashimo
- Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts; Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Mehmet K Samur
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts
| | - Nikhil C Munshi
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts; Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Masood A Shammas
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts; Hematology and Oncology, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts.
| |
Collapse
|
4
|
Ogiya D, Chyra Z, Verselis SJ, O'Keefe M, Cobb J, Abiatari I, Talluri S, Sithara AA, Hideshima T, Chu MP, Hájek R, Dorfman DM, Pilarski LM, Anderson KC, Adamia S. Identification of disease-related aberrantly spliced transcripts in myeloma and strategies to target these alterations by RNA-based therapeutics. Blood Cancer J 2023; 13:23. [PMID: 36737429 PMCID: PMC9898564 DOI: 10.1038/s41408-023-00791-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 12/17/2022] [Accepted: 01/12/2023] [Indexed: 02/05/2023] Open
Abstract
Novel drug discoveries have shifted the treatment paradigms of most hematological malignancies, including multiple myeloma (MM). However, this plasma cell malignancy remains incurable, and novel therapies are therefore urgently needed. Whole-genome transcriptome analyses in a large cohort of MM patients demonstrated that alterations in pre-mRNA splicing (AS) are frequent in MM. This manuscript describes approaches to identify disease-specific alterations in MM and proposes RNA-based therapeutic strategies to eradicate such alterations. As a "proof of concept", we examined the causes of aberrant HMMR (Hyaluronan-mediated motility receptor) splicing in MM. We identified clusters of single nucleotide variations (SNVs) in the HMMR transcript where the altered splicing took place. Using bioinformatics tools, we predicted SNVs and splicing factors that potentially contribute to aberrant HMMR splicing. Based on bioinformatic analyses and validation studies, we provided the rationale for RNA-based therapeutic strategies to selectively inhibit altered HMMR splicing in MM. Since splicing is a hallmark of many cancers, strategies described herein for target identification and the design of RNA-based therapeutics that inhibit gene splicing can be applied not only to other genes in MM but also more broadly to other hematological malignancies and solid tumors as well.
Collapse
Affiliation(s)
- Daisuke Ogiya
- Department of Hematology and Oncology, Tokai University School of Medicine, Isehara, Japan
| | - Zuzana Chyra
- Department of Hemato-oncology, University Hospital Ostrava, Ostrava, Czech Republic.,Department of Hemato-oncology, University of Ostrava, Ostrava, Czech Republic
| | - Sigitas J Verselis
- Molecular Diagnostic Laboratory, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Morgan O'Keefe
- Jerome Lipper Multiple Myeloma Disease Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Jacquelyn Cobb
- Jerome Lipper Multiple Myeloma Disease Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Ivane Abiatari
- Institute of Medical and Public Health Research, School of Medicine, Ilia State University, Tbilisi, Georgia
| | - Srikanth Talluri
- Molecular Diagnostic Laboratory, Dana-Farber Cancer Institute, Boston, MA, USA.,Veterans Administration Boston Healthcare System, West Roxbury, MA, USA
| | - Anjana Anilkumar Sithara
- Department of Hemato-oncology, University Hospital Ostrava, Ostrava, Czech Republic.,Department of Hemato-oncology, University of Ostrava, Ostrava, Czech Republic
| | - Teru Hideshima
- Jerome Lipper Multiple Myeloma Disease Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Michael P Chu
- Department of Medicine, Department of Oncology, University of Alberta, Edmonton, AB, Canada
| | - Roman Hájek
- Department of Hemato-oncology, University Hospital Ostrava, Ostrava, Czech Republic.,Department of Hemato-oncology, University of Ostrava, Ostrava, Czech Republic
| | - David M Dorfman
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Linda M Pilarski
- Department of Medicine, Department of Oncology, University of Alberta, Edmonton, AB, Canada
| | - Kenneth C Anderson
- Jerome Lipper Multiple Myeloma Disease Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
| | - Sophia Adamia
- Jerome Lipper Multiple Myeloma Disease Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA. .,Institute of Medical and Public Health Research, School of Medicine, Ilia State University, Tbilisi, Georgia. .,Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
5
|
Morelli E, Fulciniti M, Samur MK, Ribeiro CF, Wert-Lamas L, Henninger JE, Gullà A, Aktas-Samur A, Todoerti K, Talluri S, Park WD, Federico C, Scionti F, Amodio N, Bianchi G, Johnstone M, Liu N, Gramegna D, Maisano D, Russo NA, Lin C, Tai YT, Neri A, Chauhan D, Hideshima T, Shammas MA, Tassone P, Gryaznov S, Young RA, Anderson KC, Novina CD, Loda M, Munshi NC. A MIR17HG-derived long noncoding RNA provides an essential chromatin scaffold for protein interaction and myeloma growth. Blood 2023; 141:391-405. [PMID: 36126301 PMCID: PMC10082365 DOI: 10.1182/blood.2022016892] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 09/08/2022] [Accepted: 09/13/2022] [Indexed: 01/31/2023] Open
Abstract
Long noncoding RNAs (lncRNAs) can drive tumorigenesis and are susceptible to therapeutic intervention. Here, we used a large-scale CRISPR interference viability screen to interrogate cell-growth dependency to lncRNA genes in multiple myeloma (MM) and identified a prominent role for the miR-17-92 cluster host gene (MIR17HG). We show that an MIR17HG-derived lncRNA, named lnc-17-92, is the main mediator of cell-growth dependency acting in a microRNA- and DROSHA-independent manner. Lnc-17-92 provides a chromatin scaffold for the functional interaction between c-MYC and WDR82, thus promoting the expression of ACACA, which encodes the rate-limiting enzyme of de novo lipogenesis acetyl-coA carboxylase 1. Targeting MIR17HG pre-RNA with clinically applicable antisense molecules disrupts the transcriptional and functional activities of lnc-17-92, causing potent antitumor effects both in vitro and in vivo in 3 preclinical animal models, including a clinically relevant patient-derived xenograft NSG mouse model. This study establishes a novel oncogenic function of MIR17HG and provides potent inhibitors for translation to clinical trials.
Collapse
Affiliation(s)
- Eugenio Morelli
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Mariateresa Fulciniti
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Mehmet K. Samur
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Caroline F. Ribeiro
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY
| | - Leon Wert-Lamas
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA
| | - Jon E. Henninger
- Whitehead Institute of Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA
| | - Annamaria Gullà
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Anil Aktas-Samur
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Katia Todoerti
- Department of Hematology, Fondazione Cà Granda IRCCS Policlinico, Milan, Italy
| | - Srikanth Talluri
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| | - Woojun D. Park
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
| | - Cinzia Federico
- Department of Clinical and Experimental Medicine, Magna Graecia University, Catanzaro, Italy
| | - Francesca Scionti
- Department of Clinical and Experimental Medicine, Magna Graecia University, Catanzaro, Italy
- Clinical Research Development and Phase I Unit, ASST Spedali Civili di Brescia, Brescia, Italy
| | - Nicola Amodio
- Department of Clinical and Experimental Medicine, Magna Graecia University, Catanzaro, Italy
| | - Giada Bianchi
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Megan Johnstone
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
| | - Na Liu
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
| | - Doriana Gramegna
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Domenico Maisano
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Nicola A. Russo
- Istituto di Ricerche Genetiche “G. Salvatore,” Biogem s.c.ar.l., Avellino, Italy
| | - Charles Lin
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
| | - Yu-Tzu Tai
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Antonino Neri
- Department of Hematology, Fondazione Cà Granda IRCCS Policlinico, Milan, Italy
- Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy
- Scientific Directorate, Azienda USL-IRCCS Reggio Emilia, Reggio Emilia, Italy
| | - Dharminder Chauhan
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Teru Hideshima
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Masood A. Shammas
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| | - Pierfrancesco Tassone
- Department of Clinical and Experimental Medicine, Magna Graecia University, Catanzaro, Italy
| | | | - Richard A. Young
- Whitehead Institute of Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA
| | - Kenneth C. Anderson
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
| | - Carl D. Novina
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA
| | - Massimo Loda
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY
| | - Nikhil C. Munshi
- Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, Boston, MA
- Harvard Medical School, Boston, MA
- VA Boston Healthcare System, Boston, MA
| |
Collapse
|
6
|
Liao C, Talluri S, Zhao J, Mu S, Kumar S, Shi J, Buon L, Munshi NC, Shammas MA. RAD51 Is Implicated in DNA Damage, Chemoresistance and Immune Dysregulation in Solid Tumors. Cancers (Basel) 2022; 14:cancers14225697. [PMID: 36428789 PMCID: PMC9688595 DOI: 10.3390/cancers14225697] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 11/09/2022] [Accepted: 11/10/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND In normal cells, homologous recombination (HR) is tightly regulated and plays an important role in the maintenance of genomic integrity and stability through precise repair of DNA damage. RAD51 is a recombinase that mediates homologous base pairing and strand exchange during DNA repair by HR. Our previous data in multiple myeloma and esophageal adenocarcinoma (EAC) show that dysregulated HR mediates genomic instability. Purpose of this study was to investigate role of HR in genomic instability, chemoresistance and immune dysregulation in solid tumors including colon and breast cancers. METHODS The GEO dataset were used to investigate correlation of RAD51 expression with patient survival and expression of various immune markers in EAC, breast and colorectal cancers. RAD51 was inhibited in cancer cell lines using shRNAs and a small molecule inhibitor. HR activity was evaluated using a plasmid-based assay, DNA breaks assessed by evaluating expression of γ-H2AX (a marker of DNA breaks) and p-RPA32 (a marker of DNA end resection) using Western blotting. Genomic instability was monitored by investigating micronuclei (a marker of genomic instability). Impact of RAD51 inhibitor and/or a DNA-damaging agent was assessed on viability and apoptosis in EAC, breast and colon cancer cell lines in vitro and in a subcutaneous tumor model of EAC. Impact of RAD51 inhibitor on expression profile was monitored by RNA sequencing. RESULTS Elevated RAD51 expression correlated with poor survival of EAC, breast and colon cancer patients. RAD51 knockdown in cancer cell lines inhibited DNA end resection and strand exchange activity (key steps in the initiation of HR) as well as spontaneous DNA breaks, whereas its overexpression increased DNA breaks and genomic instability. Treatment of EAC, colon and breast cancer cell lines with a small molecule inhibitor of RAD51 inhibited DNA breaking agent-induced DNA breaks and genomic instability. RAD51 inhibitor potentiated cytotoxicity of DNA breaking agent in all cancer cell types tested in vitro as well as in a subcutaneous model of EAC. Evaluation by RNA sequencing demonstrated that DNA repair and cell cycle related pathways were induced by DNA breaking agent whereas their induction either prevented or reversed by RAD51 inhibitor. In addition, immune-related pathways such as PD-1 and Interferon Signaling were also induced by DNA breaking agent whereas their induction prevented by RAD51 inhibitor. Consistent with these observations, elevated RAD51 expression also correlated with that of genes involved in inflammation and other immune surveillance. CONCLUSIONS Elevated expression of RAD51 and associated HR activity is involved in spontaneous and DNA damaging agent-induced DNA breaks and genomic instability thus contributing to chemoresistance, immune dysregulation and poor prognosis in cancer. Therefore, inhibitors of RAD51 have great potential as therapeutic agents for EAC, colon, breast and probably other solid tumors.
Collapse
Affiliation(s)
- Chengcheng Liao
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
- VA Health Care System, Boston, MA 02215, USA
- Department of Hematology/Oncology, Guangxi Medical University Cancer Hospital, Nanning 530021, China
| | - Srikanth Talluri
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
- VA Health Care System, Boston, MA 02215, USA
| | - Jiangning Zhao
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
- VA Health Care System, Boston, MA 02215, USA
| | - Shidai Mu
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
- VA Health Care System, Boston, MA 02215, USA
| | - Subodh Kumar
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
- VA Health Care System, Boston, MA 02215, USA
| | - Jialan Shi
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
- VA Health Care System, Boston, MA 02215, USA
- Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Leutz Buon
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
| | - Nikhil C. Munshi
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
- VA Health Care System, Boston, MA 02215, USA
- Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Masood A. Shammas
- Department of Adult Oncology, Harvard (Dana Farber) Cancer Institute, 450 Brookline Ave, Boston, MA 02215, USA
- VA Health Care System, Boston, MA 02215, USA
- Correspondence:
| |
Collapse
|
7
|
Rajagopal T, Seshachalam A, Jothi A, Rathnam KK, Talluri S, Venkatabalasubranian S, Dunna NR. Analysis of pathogenic variants in BRCA1 and BRCA2 genes using next-generation sequencing in women with triple negative breast cancer from South India. Mol Biol Rep 2022; 49:3025-3032. [PMID: 35020120 DOI: 10.1007/s11033-022-07129-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 01/05/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND The frequency of triple-negative breast cancer (TNBC) incidence varies among different populations suggesting the involvement of genetic components towards TNBC development. Previous studies have reported that BRCA1/2 germline mutations confer a lifetime risk of developing TNBC. However, there is hardly any information regarding the common pathogenic variants (PVs) in BRCA1/2 genes that contribute to TNBC in the Indian population. Hence, we screened for PVs in BRCA1/2 and their association with clinico-pathological features in TNBC patients. METHODS AND RESULTS The study recruited 59 TNBC patients without hereditary breast and ovarian cancer (HBOC) from South India. The entire BRCA1 and BRCA2 genes were sequenced for the 59 patients using the Illumina HiSeq X Ten sequencer. Among the 59 TNBC genomic DNA samples sequenced, BRCA mutations were identified in 8 patients (13.6%), BRCA1 mutations in 6 patients, and BRCA2 mutations in 2 patients. Among the 6 BRCA1 mutations, three were c.68_69delAG (185delAG) mutation. Remarkably, all the TNBC patients with BRCA mutations exhibited higher-grade tumors (grade 2 or 3). However, among all the BRCA mutation carriers, only one patient with a BRCA2 mutation (p.Glu1879Lys) developed metastasis. CONCLUSION Our data advocates that South Indian women with higher grade TNBC tumors and without HBOC could be considered for BRCA mutation screening, thereby enabling enhanced decision-making and preventive therapy.
Collapse
Affiliation(s)
- Taruna Rajagopal
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Arun Seshachalam
- Department of Medical and Paediatric Oncology, Dr.G.V.N Cancer Institute, Singarathope, Trichy, 620 008, India
| | - Arunachalam Jothi
- Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Krishna Kumar Rathnam
- Department of Hemato Oncology - Medical Oncology and Bone Marrow Transplantation, Meenakshi Mission Hospital & Research Centre, Madurai, 625 107, India
| | - Srikanth Talluri
- Dana Farber Cancer Institute, Boston, MA, 02215, USA
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | - Sivaramakrishnan Venkatabalasubranian
- Department of Genetic Engineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur Campus, Chennai, Tamil Nadu, 603 203, India
| | - Nageswara Rao Dunna
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India.
| |
Collapse
|
8
|
Rajagopal T, Seshachalam A, Rathnam KK, Talluri S, Venkatabalasubramanian S, Dunna NR. Homologous recombination DNA repair gene RAD51, XRCC2 & XRCC3 polymorphisms and breast cancer risk in South Indian women. PLoS One 2022; 17:e0259761. [PMID: 35061678 PMCID: PMC8782413 DOI: 10.1371/journal.pone.0259761] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 10/26/2021] [Indexed: 01/04/2023] Open
Abstract
Background Homologous recombination repair (HRR) accurately repairs the DNA double-strand breaks (DSBs) and is crucial for genome stability. Genetic polymorphisms in crucial HRR pathway genes might affect genome stability and promote tumorigenesis. Up to our knowledge, the present study is the first to investigate the impact of HRR gene polymorphisms on BC development in South Indian women. The present population-based case-control study investigated the association of polymorphisms in three key HRR genes (XRCC2-Arg188His, XRCC3-Thr241Met and RAD51-G135C) with BC risk. Materials and methods Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used for genotyping the HRR variants in 491 BC cases and 493 healthy women. Results We observed that the XRCC3 Met allele was significantly associated with BC risk [OR:1.27 (95% CI: 1.02–1.60); p = 0.035]. In addition, the homozygous mutant (C/C) genotype of RAD51 G135C variant conferred 2.19 fold elevated risk of BC [OR: 2.19 (95% CI: 1.06–4.54); p = 0.034]. Stratified analysis of HRR variants and BC clinicopathological features revealed that the XRCC3-Thr241Met and RAD51-G135C variants are associated with BC progression. Combined SNP analysis revealed that the individuals with RAD51-C/C, XRCC2-Arg/Arg, and XRCC3-Thr/Thr genotype combination have three-fold increased BC risk. Conclusion The present study imparts additional evidence that genetic variants in crucial HRR pathway genes might play a pivotal role in modulating BC risk in South Indian women.
Collapse
Affiliation(s)
- Taruna Rajagopal
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA–Deemed University, Thanjavur, India
| | - Arun Seshachalam
- Department of Medical and Paediatric Oncology, Dr.G.V.N Cancer Institute, Singarathope, Trichy, India
| | - Krishna Kumar Rathnam
- Department of Hemato Oncology–Medical Oncology and Bone Marrow Transplantation, Meenakshi Mission Hospital & Research Centre, Madurai, India
| | - Srikanth Talluri
- Dana Farber Cancer Institute, Boston, MA, United States of America
- Veterans Administration Boston Healthcare System, West Roxbury, MA, United States of America
| | | | - Nageswara Rao Dunna
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA–Deemed University, Thanjavur, India
- * E-mail:
| |
Collapse
|
9
|
Talluri S, Samur MK, Buon L, Kumar S, Potluri LB, Shi J, Prabhala RH, Shammas MA, Munshi NC. Dysregulated APOBEC3G causes DNA damage and promotes genomic instability in multiple myeloma. Blood Cancer J 2021; 11:166. [PMID: 34625538 PMCID: PMC8501035 DOI: 10.1038/s41408-021-00554-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 08/14/2021] [Accepted: 09/01/2021] [Indexed: 12/22/2022] Open
Abstract
Multiple myeloma (MM) is a heterogeneous disease characterized by significant genomic instability. Recently, a causal role for the AID/APOBEC deaminases in inducing somatic mutations in myeloma has been reported. We have identified APOBEC/AID as a prominent mutational signature at diagnosis with further increase at relapse in MM. In this study, we identified upregulation of several members of APOBEC3 family (A3A, A3B, A3C, and A3G) with A3G, as one of the most expressed APOBECs. We investigated the role of APOBEC3G in MM and observed that A3G expression and APOBEC deaminase activity is elevated in myeloma cell lines and patient samples. Loss-of and gain-of function studies demonstrated that APOBEC3G significantly contributes to increase in DNA damage (abasic sites and DNA breaks) in MM cells. Evaluation of the impact on genome stability, using SNP arrays and whole genome sequencing, indicated that elevated APOBEC3G contributes to ongoing acquisition of both the copy number and mutational changes in MM cells over time. Elevated APOBEC3G also contributed to increased homologous recombination activity, a mechanism that can utilize increased DNA breaks to mediate genomic rearrangements in cancer cells. These data identify APOBEC3G as a novel gene impacting genomic evolution and underlying mechanisms in MM.
Collapse
Affiliation(s)
- Srikanth Talluri
- Dana Farber Cancer Institute, Boston, MA, 02115, USA
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | | | - Leutz Buon
- Dana Farber Cancer Institute, Boston, MA, 02115, USA
| | - Subodh Kumar
- Dana Farber Cancer Institute, Boston, MA, 02115, USA
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | - Lakshmi B Potluri
- Dana Farber Cancer Institute, Boston, MA, 02115, USA
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | - Jialan Shi
- Dana Farber Cancer Institute, Boston, MA, 02115, USA
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | - Rao H Prabhala
- Dana Farber Cancer Institute, Boston, MA, 02115, USA
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
- Harvard Medical School, Boston, MA, 02215, USA
| | - Masood A Shammas
- Dana Farber Cancer Institute, Boston, MA, 02115, USA
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | - Nikhil C Munshi
- Dana Farber Cancer Institute, Boston, MA, 02115, USA.
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA.
- Harvard Medical School, Boston, MA, 02215, USA.
| |
Collapse
|
10
|
Gulla A, Morelli E, Samur MK, Botta C, Hideshima T, Bianchi G, Fulciniti M, Malvestiti S, Prabhala RH, Talluri S, Wen K, Tai YT, Richardson PG, Chauhan D, Sewastianik T, Carrasco RD, Munshi NC, Anderson KC. Bortezomib induces anti-multiple myeloma immune response mediated by cGAS/STING pathway activation. Blood Cancer Discov 2021; 2:468-483. [PMID: 34568832 DOI: 10.1158/2643-3230.bcd-21-0047] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Proteasome inhibitor bortezomib induces apoptosis in multiple myeloma (MM) cells, and has transformed patient outcome. Using in vitro as well as in vivo immunodeficient and immunocompetent murine MM models, we here show that bortezomib also triggers immunogenic cell death (ICD) characterized by exposure of calreticulin on dying MM cells, phagocytosis of tumor cells by dendritic cells, and induction of MM specific immunity. We identify a bortezomib-triggered specific ICD-gene signature associated with better outcome in two independent MM patient cohorts. Importantly, bortezomib stimulates MM cells immunogenicity via activation of cGAS/STING pathway and production of type-I interferons; and STING agonists significantly potentiate bortezomib-induced ICD. Our studies therefore delineate mechanisms whereby bortezomib exerts immunotherapeutic activity, and provide the framework for clinical trials of STING agonists with bortezomib to induce potent tumor-specific immunity and improve patient outcome in MM.
Collapse
Affiliation(s)
- Annamaria Gulla
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Eugenio Morelli
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Mehmet K Samur
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA.,Department of Data Sciences, Dana Farber Cancer Institute, Boston, MA.,Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA
| | - Cirino Botta
- Department of Oncohematology, "Annunziata" Hospital, Cosenza, Italy
| | - Teru Hideshima
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Giada Bianchi
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard medical School, Boston, MA
| | - Mariateresa Fulciniti
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Stefano Malvestiti
- Freiburg University Hospital, Department of Pediatric hematology and Oncology, Germany
| | - Rao H Prabhala
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA.,VA Boston Healthcare System, Boston, MA
| | - Srikanth Talluri
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA.,VA Boston Healthcare System, Boston, MA
| | - Kenneth Wen
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Yu-Tzu Tai
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Paul G Richardson
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Dharminder Chauhan
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Tomasz Sewastianik
- Department of Oncologic Pathology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA.,Department of Experimental Hematology, Institute of Hematology and Transfusion Medicine, Warsaw, Poland
| | - Ruben D Carrasco
- Department of Oncologic Pathology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA.,Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Nikhil C Munshi
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA.,VA Boston Healthcare System, Boston, MA
| | - Kenneth C Anderson
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| |
Collapse
|
11
|
Kumar S, Buon L, Talluri S, Roncador M, Liao C, Zhao J, Shi J, Chakraborty C, Gonzalez G, Tai YT, Prabhala R, Samur MK, Munshi NC, Shammas MA. Integrated genomics and comprehensive validation reveal drivers of genomic evolution in esophageal adenocarcinoma. Commun Biol 2021; 4:617. [PMID: 34031527 PMCID: PMC8144613 DOI: 10.1038/s42003-021-02125-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 04/16/2021] [Indexed: 12/13/2022] Open
Abstract
Esophageal adenocarcinoma (EAC) is associated with a marked genomic instability, which underlies disease progression and development of resistance to treatment. In this study, we used an integrated genomics approach to identify a genomic instability signature. Here we show that elevated expression of this signature correlates with poor survival in EAC as well as three other cancers. Knockout and overexpression screens establish the relevance of these genes to genomic instability. Indepth evaluation of three genes (TTK, TPX2 and RAD54B) confirms their role in genomic instability and tumor growth. Mutational signatures identified by whole genome sequencing and functional studies demonstrate that DNA damage and homologous recombination are common mechanisms of genomic instability induced by these genes. Our data suggest that the inhibitors of TTK and possibly other genes identified in this study have potential to inhibit/reduce growth and spontaneous as well as chemotherapy-induced genomic instability in EAC and possibly other cancers. Subodh Kumar et al. identify a gene signature correlated with genomic instability and poor survival in esophageal adenocarcinoma (EAC), using a combination of integrative genomic analysis of patient data and laboratory validation in cell line models and mice. They find that inhibitors of some of the identified proteins, including TTK, could be used to reduce genomic evolution as well as inhibit growth of EAC cells.
Collapse
Affiliation(s)
- Subodh Kumar
- Dana Farber Cancer Institute, Boston, MA, USA.,Veterans Administration Healthcare System, Boston, MA, USA
| | - Leutz Buon
- Dana Farber Cancer Institute, Boston, MA, USA
| | - Srikanth Talluri
- Dana Farber Cancer Institute, Boston, MA, USA.,Veterans Administration Healthcare System, Boston, MA, USA
| | | | - Chengcheng Liao
- Dana Farber Cancer Institute, Boston, MA, USA.,Veterans Administration Healthcare System, Boston, MA, USA
| | - Jiangning Zhao
- Dana Farber Cancer Institute, Boston, MA, USA.,Veterans Administration Healthcare System, Boston, MA, USA
| | - Jialan Shi
- Dana Farber Cancer Institute, Boston, MA, USA.,Veterans Administration Healthcare System, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | | | - Gabriel Gonzalez
- Veterans Administration Healthcare System, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Yu-Tzu Tai
- Dana Farber Cancer Institute, Boston, MA, USA
| | - Rao Prabhala
- Dana Farber Cancer Institute, Boston, MA, USA.,Veterans Administration Healthcare System, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | | | - Nikhil C Munshi
- Dana Farber Cancer Institute, Boston, MA, USA.,Veterans Administration Healthcare System, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Masood A Shammas
- Dana Farber Cancer Institute, Boston, MA, USA. .,Veterans Administration Healthcare System, Boston, MA, USA.
| |
Collapse
|
12
|
Talluri S, Palaparthi SM, Michelogiannakis D, Khan J. Efficacy of photobiomodulation in the management of tinnitus: A systematic review of randomized control trials. Eur Ann Otorhinolaryngol Head Neck Dis 2021; 139:83-90. [PMID: 33685826 DOI: 10.1016/j.anorl.2020.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/03/2020] [Accepted: 10/21/2020] [Indexed: 11/24/2022]
Abstract
There is a controversy in regards to the efficacy of photobiomodulation (PBM) in the management of tinnitus. The aim was to systematically review randomized controlled trials (RCTs) that assessed the efficacy of PBM (low-level laser therapy) in the management of tinnitus. The focused question was "Is PBM effective in the management of tinnitus?". Indexed databases were searched up to and including June 2020 using different combinations of the following key words: (a) laser; (b) diode; (c) low-level laser therapy; (d) photobiomodulation; (e) tinnitus; (f) medium-level laser; (g) photo-biomodulation; and (h) low-power laser; and RCTs performed on humans were included. Letters to the editor; case reports/series; commentaries; experimental studies and historic reviews were excluded. The risk of bias was assessed using the modified cochrane collaboration tool. The format of the current systematic review was personalized to summarize the appropriate information. Ten RCTs (2 single-blinded and 8 double-blinded) were included. One study reported 30% and 100% resolution of tinnitus using diode and Neodymium-doped Yttrium Aluminum Garnet lasers; respectively. One study reported that PBM was effective in relieving tinnitus for up to 3 months. Eight studies reported that PBM was ineffective in the management of chronic tinnitus. The risk of bias was high; medium and low in 4; 5 and 1 studies; respectively. The effectiveness of PBM in the management of tinnitus remains debatable. Further power-adjusted and well-designed RCTs with long-term follow-up are needed.
Collapse
Affiliation(s)
- S Talluri
- Orofacial Pain and TMJD, Eastman Institute for Oral Health, Rochester, 625 Elmwood Ave, Rochester, NY 14620, USA
| | - S M Palaparthi
- Vijay Super Specialty Dental Hospital, Guptha's square, Ongole, AP 530013, India
| | - D Michelogiannakis
- Department of Orthodontics, Eastman Institute for Oral Health, Rochester, 625 Elmwood Ave, Rochester, NY 14620, USA
| | - J Khan
- Orofacial Pain and TMJD, Eastman Institute for Oral Health, Rochester, 625 Elmwood Ave, Rochester, NY 14620, USA.
| |
Collapse
|
13
|
Rajagopal T, Seshachalam A, Rathnam KK, Jothi A, Talluri S, Venkatabalasubramanian S, Dunna NR. Impact of xenobiotic-metabolizing gene polymorphisms on breast cancer risk in South Indian women. Breast Cancer Res Treat 2021; 186:823-837. [PMID: 33392841 DOI: 10.1007/s10549-020-06028-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 11/16/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Functional variants of the xenobiotic-metabolizing genes (XMG) might modulate breast cancer (BC) risk by altering the rate of metabolism and clearance of myriad types of potent carcinogens from the breast tissue. Despite mounting evidence on the role of XMG variants on BC risk, the current knowledge regarding their influence on BC development is still fragmentary. METHODS The present study examined the candidate genetic variants in CYP1A1, NQO1, GST-T1, GST-M1, and GST-P1 in 1002 subjects (502 BC patients and 500 disease-free women). PCR-RFLP was employed to genotype the mono-nucleotide variation in CYP1A1, NQO1, and GST-P1, and allele-specific PCR was used to detect the deletion polymorphism in GST-T1 and GST-M1 genes. RESULTS Regarding CYP1A1-M1 polymorphism, the heterozygous TC and mutant CC genotype conferred 1.47-fold (95% CI 1.13-1.91, p = 0.004) and 1.84-fold (95% CI 1.17-2.91, p = 0.009) elevated risk of BC. GST-T1 null genotype was associated with increased BC risk (OR 1.47; 95% CI 1.02-2.11, p = 0.037). For the NQO1 C609T variant, the mutant T allele was associated with BC risk with an odds ratio of 1.22 (95% CI 1.02-1.48, p = 0.034). Combinatorial analysis indicated that the presence of NQO1*2 (CT), CYP1A1-M1 (CC), and GST-P1 rs1695 (AG) genotypes conferred 16.7-fold elevated risk of BC (95% CI 3.65-76.85; p < 0.001). Moreover, GST-M1 null genotype was associated with the development of larger primary breast tumors. CONCLUSION Xenobiotic-metabolizing gene polymorphisms may play a crucial role in mammary carcinogenesis in South Indian women.
Collapse
Affiliation(s)
- Taruna Rajagopal
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Arun Seshachalam
- Department of Medical and Paediatric Oncology, Dr.G.V.N Cancer Institute, Singarathope, Trichy, 620 008, India
| | - Krishna Kumar Rathnam
- Department of Hemato Oncology - Medical Oncology and Bone Marrow Transplantation, Meenakshi Mission Hospital & Research Centre, Madurai, 625 107, India
| | - Arunachalam Jothi
- Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Srikanth Talluri
- Dana Farber Cancer Institute, Boston, MA, 02215, USA.,Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | - Sivaramakrishnan Venkatabalasubramanian
- Department of Genetic Engineering, Faculty of Engineering and Technology, SRM Institute of Medical Science and Technology, Kattankulathur Campus, Chennai, 603 203, India
| | - Nageswara Rao Dunna
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India.
| |
Collapse
|
14
|
Sharma RK, Kumar A, Yamada Y, Tanaka R, Sharma S, Miyatani K, Higashiguchi S, Kawase T, Talluri S, Kato Y. Institutional Experience of Microsurgical Management in Posterior Circulation Aneurysm. Asian J Neurosurg 2020; 15:484-493. [PMID: 33145196 PMCID: PMC7591165 DOI: 10.4103/ajns.ajns_69_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 04/01/2020] [Accepted: 05/12/2020] [Indexed: 11/28/2022] Open
Abstract
Introduction: Posterior circulation aneurysm constitutes 15%–20% of all intracerebral aneurysms. With the advancement of endovascular techniques, the microsurgery for posterior circulation aneurysms has been pushed back a little. Even the International Subarachnoid Aneurysmal Trial gave support to the concepts of endovascular procedures, but microsurgical modality should not be discouraged. We present our institutional experience of microsurgical techniques on posterior circulation aneurysms. Materials and Methods: We performed a retrospective analysis of 37 patients of posterior circulation aneurysm from 2015 to 2019, referred to Bantane Hospital, Japan. We included all posterior circulation aneurysms such as basilar tip, basilar trunk, and vertebral artery-posterior inferior cerebellar artery (VA-PICA) aneurysms, admitted and treated with clipping or bypass and trapping. We assessed the outcome as measured by modified Rankin Score (mRS), complications, and mortality. Results: Out of 37 patients, 10 cases were a basilar tip, one case was the basilar trunk, and 26 cases were VA-PICA aneurysm. Intraoperatively, neuromonitoring, indocyanine green dye, dual-image videoangiography (DIVA), and neuro endoscope were used. Two patients of basilar tip aneurysm developed third cranial nerve paresis and six patients of VA-PICA aneurysm developed lower cranial nerve paresis which resolved spontaneously. All the patients were discharged with mRS of 0 or 1. No mortality was recorded in our study. Conclusion: Microsurgical clipping of posterior circulation aneurysm is safe in unruptured aneurysm with a very low risk of mortality and morbidity under experienced hands. All postoperative complications in our study were transient and resolved with time with no residual deficits. Preoperative simulation, intraoperative neuromonitoring, DIVA, and neuro endoscope help achieve complete obliteration of aneurysmal sac and avoid complications.
Collapse
Affiliation(s)
| | - Ambuj Kumar
- Department of Neurosurgery, N.S.C.B. Medical College, Jabalpur, Madhya Pradesh, India
| | - Yasuhiro Yamada
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Riki Tanaka
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Saurabh Sharma
- Department of Neurosurgery, Max Hospital, New Delhi, India
| | - Kyosuke Miyatani
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Saeko Higashiguchi
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Tsukasa Kawase
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Srikanth Talluri
- Department of Neurosurgery, SVIMS, Tirupati, Andhra Pradesh, India
| | - Yoko Kato
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| |
Collapse
|
15
|
Sharma RK, Yamada Y, Tanaka R, Sharma S, Miyatani K, Higashiguchi S, Kawase T, Talluri S, Kato Y. Unusually Located Proximal Middle Cerebral Artery Saccular Aneurysm. Asian J Neurosurg 2020; 15:769-772. [PMID: 33145252 PMCID: PMC7591176 DOI: 10.4103/ajns.ajns_264_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/28/2019] [Accepted: 06/06/2020] [Indexed: 11/04/2022] Open
Abstract
Middle cerebral aneurysms constitute almost one-third of all anterior circulation aneurysms. Most of the saccular aneurysms originate from the arterial branching sites, but origins other than at the branching site are extremely rare. In this article, we are describing a unique M1 segment middle cerebral artery aneurysm which is not related with any branching site. Our literature search suggests that atherosclerotic changes in the arterial wall and local hemodynamic forces play an important role in the development of these types of aneurysm. Surgical management is not so unique in this type of aneurysm, but due to atherosclerotic parent arterial wall and thin-walled aneurysm sac, a neurosurgeon should be more cautious.
Collapse
Affiliation(s)
| | - Yashuhiro Yamada
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Riki Tanaka
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Saurabh Sharma
- Department of Neurosurgery, Max Patparganj Hospital, New Delhi, India
| | - Kyosuke Miyatani
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Saeko Higashiguchi
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Tsukasa Kawase
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Srikanth Talluri
- Department of Neurosurgery, SVIMS, Tirupati, Andhra Pradesh, India
| | - Yoko Kato
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| |
Collapse
|
16
|
Liao C, Zhao J, Kumar S, Chakraborty C, Talluri S, Munshi NC, Shammas MA. RAD51 Inhibitor Reverses Etoposide-Induced Genomic Toxicity and Instability in Esophageal Adenocarcinoma Cells. Arch Clin Toxicol (Middlet) 2020; 2:3-9. [PMID: 32968740 PMCID: PMC7508453 DOI: 10.46439/toxicology.2.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Aim: In normal cells, homologous recombination (HR) is strictly regulated and precise and plays an important role in preserving genomic integrity by accurately repairing DNA damage. RAD51 is the recombinase which mediates homologous base pairing and strand exchange during DNA repair by HR. We have previously reported that HR is spontaneously elevated (or dysregulated) in esophageal adenocarcinoma (EAC) and contributes to ongoing genomic changes and instability. The purpose of this study was to evaluate the impact of RAD51 inhibitor on genomic toxicity caused by etoposide, a chemotherapeutic agent. Methods: EAC cell lines (FLO-1 and OE19) were cultured in the presence of RAD51 inhibitor and/or etoposide, and impact on cell viability, apoptosis and genomic integrity/stability investigated. Genomic integrity/stability was monitored by evaluating cells for γ-H2AX (a marker for DNA breaks), phosphorylated RPA32 (a marker of DNA end resection which is a distinct step in the initiation of HR) and micronuclei (a marker of genomic instability). Results: Treatment with etoposide, a chemotherapeutic agent, was associated with marked genomic toxicity (as evident from increase in DNA breaks) and genomic instability in both EAC cell lines. Consistently, the treatment was also associated with apoptotic cell death. A small molecule inhibitor of RAD51 increased cytotoxicity while reducing genomic toxicity and instability caused by etoposide, in both EAC cell lines. Conclusion: RAD51 inhibitors have potential to increase cytotoxicity while reducing harmful genomic impact of chemotherapy.
Collapse
Affiliation(s)
- Chengcheng Liao
- Dana Farber Cancer Institute, USA.,Veterans Administration Boston Healthcare System, USA
| | | | - Subodh Kumar
- Dana Farber Cancer Institute, USA.,Veterans Administration Boston Healthcare System, USA
| | | | - Srikanth Talluri
- Dana Farber Cancer Institute, USA.,Veterans Administration Boston Healthcare System, USA
| | - Nikhil C Munshi
- Dana Farber Cancer Institute, USA.,Veterans Administration Boston Healthcare System, USA.,Harvard Medical School, USA
| | - Masood A Shammas
- Dana Farber Cancer Institute, USA.,Veterans Administration Boston Healthcare System, USA
| |
Collapse
|
17
|
Sharma RK, Yamada Y, Tanaka R, Sharma S, Miyatani K, Higashiguchi S, Kawase T, Talluri S, Kato Y. Minimally Invasive Anterolateral Approach for C2 Neurofibroma in Elderly Patient. Asian J Neurosurg 2020; 15:759-762. [PMID: 33145249 PMCID: PMC7591177 DOI: 10.4103/ajns.ajns_252_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 09/23/2019] [Accepted: 05/04/2020] [Indexed: 11/17/2022] Open
Abstract
Conventionally ventrally located spinal tumor is approached through anterior vertebrectomy which requires bony fixation and then immobilization for a couple of months. The alternative route to deal with such type of tumor is anterolaterally to avoid the surgical and nonsurgical complications. We are reporting a minimally invasive anterolateral approach for C2 neurofibroma in an 84-year-old patient. Postoperatively this patient did not require cervical brace and postoperative discomfort was minimal. It was observed that dumbbell-shaped cervical tumor with no intradural pathology and wide neural foramina could also be taken care through the anterolateral route which did not require bony fusion or immobilization, but the expertise of the surgeon is necessary for performing these types of minimally invasive procedure to achieve the best results.
Collapse
Affiliation(s)
| | - Yashuhiro Yamada
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Riki Tanaka
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Saurabh Sharma
- Department of Neurosurgery, Max Hospital, Padpadganj, New Delhi, India
| | - Kyosuke Miyatani
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Saeko Higashiguchi
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Tsukasa Kawase
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| | - Srikanth Talluri
- Department of Neurosurgery, SVIMS, Tirupati, Andhra Pradesh, India
| | - Yoko Kato
- Department of Neurosurgery, Bantane Hospital, Fujita Health University, Nagoya, Japan
| |
Collapse
|
18
|
Rajagopal T, Seshachalam A, Akshaya RL, Rathnam KK, Talluri S, Jothi A, Dunna NR. Association of HOTAIR (rs920778 and rs1899663) and NME1 (rs16949649 and rs2302254) gene polymorphisms with breast cancer risk in India. Gene 2020; 762:145033. [PMID: 32781191 DOI: 10.1016/j.gene.2020.145033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/20/2020] [Accepted: 08/04/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Until now, no study has reported the combined effect of genetic variants of HOTAIR and NME1 towards breast cancer (BC) pathogenesis. Hence, the aim of the present study is to determine the risk of breast cancer development with HOTAIR (rs920778 C > T and rs1899663 G > T) and NME1 (rs16949649 T > C and rs2302254 C > T) genetic polymorphisms in the Indian population for the first time. MATERIALS AND METHODS To investigate the genetic association of these four SNPs, we conducted a population-based case-control study involving 1011 subjects (502 histologically confirmed BC patients and 509 disease-free controls) using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS HOTAIR rs920778 TC genotype elevated the risk of BC (OR = 1.39, 95% CI = 1.06-1.83, p = 0.018) and individuals carrying the mutant allele (T) of rs1899663 had increased BC risk (OR = 1.23, 95% CI = 1.02-1.47, p = 0.026). The presence of the NME1 rs16949649 CC genotype increased the risk of BC (OR = 1.76, 95% CI = 1.15-2.71, p = 0.009). Moreover, the HOTAIR rs920778 variant (TC + CC) increased the risk of BC in pre-menopausal women (OR = 5.86; p < 0.0001). Women carrying 2 or 3 mutant alleles for the investigated SNPs were observed to have an elevated risk of BC. CONCLUSION The results of the present study highlight the presence of significant associations between NME1 rs16949649 and HOTAIR (rs920778 and rs1899663) polymorphisms and breast cancer development in Indian women.
Collapse
Affiliation(s)
- Taruna Rajagopal
- Cancer Genomics Laboratory, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, India
| | - Arun Seshachalam
- Department of Medical and Paediatric Oncology, Dr.G.V.N Cancer Institute, Trichy, India
| | - R L Akshaya
- Cancer Genomics Laboratory, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, India
| | - Krishna Kumar Rathnam
- Department of Hemato Oncology - Medical Oncology and Bone Marrow Transplantation, Meenakshi Mission Hospital & Research Centre, Madurai, India
| | - Srikanth Talluri
- Dana Farber Cancer Institute, Boston, MA, USA; Veterans Administration Boston Healthcare System, West Roxbury, MA, USA
| | - Arunachalam Jothi
- Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, India
| | - Nageswara Rao Dunna
- Cancer Genomics Laboratory, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, India.
| |
Collapse
|
19
|
Balasubramanian SC, Talluri S, Kawase T, Yamada Y, Murayama K, Tanaka R, Miyatani K, Kojima D, Kato Y. Demystifying White Matter Injury in the Unconscious Patients with Diffusion Tensor Imaging. Asian J Neurosurg 2020; 15:370-376. [PMID: 32656134 PMCID: PMC7335132 DOI: 10.4103/ajns.ajns_55_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 03/20/2020] [Indexed: 11/04/2022] Open
Abstract
Background Diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) provide a noninvasive window to study the neural connectivity and reconstruct the tracts. Detection of white matter injury (WMI) by DTT is a recent application being used in stroke, diffuse axonal injury, and neurodegenerative disorders. Fiber tracking in patients with brain hemorrhage can detect loss of fibers and anatomical disruption of the tracts, which can be useful in the prognostication of patient outcome. Materials and Methods DTI and fiber tracking was done in four patients admitted at Fujita Health University Banbuntane Hospital, Japan, with decreased consciousness following brain hemorrhage (3 patients with aneurysmal subarachnoid hemorrhage and one patient with bifrontal hemorrhage), and WMI was analyzed. We also reviewed the literature on tractography in patients with brain hemorrhage and its correlation with consciousness. Results We found significant frontal WMI in the form of thinning and anatomical disruption in all four cases. The frontal white matter tracts form an important component of the limbic system and ascending reticular activating system and frontal WMI correlated with the poor conscious level and cognitive dysfunction. Structural damage to the fiber tracts demonstrated as thinning, reduction in the volume or absence on tractography with corresponding reduction in the mean fractional anisotropy values in the frontal white matter of the affected side. Conclusion DTI can be useful as a critical tool for revealing the anatomical basis for the cognitive dysfunction and unconsciousness and can be possibly used to prognosticate patient recovery. Early detection of WMI by DTI can also help in tailored rehabilitation. The authors believe that DTT could have a crucial role in the future for detecting structural changes which lead to cognitive dysfunction and further studies are needed to arrive at a specific protocol for detecting WMI.
Collapse
Affiliation(s)
- Sneha Chitra Balasubramanian
- Department of Neurosurgery, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India
| | - Srikanth Talluri
- Department of Neurosurgery, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, India
| | - Tsukasa Kawase
- Department of Neurosurgery, Fujita Health University Babuntane Hospital, Nagoya, Japan
| | - Yashuhiro Yamada
- Department of Neurosurgery, Fujita Health University Babuntane Hospital, Nagoya, Japan
| | - Kazuhiro Murayama
- Department of Radiology, Joint Research Laboratory of Advanced Medical Imaging, Fujita Health University, Toyoake, Aichi, Japan
| | - Riki Tanaka
- Department of Neurosurgery, Fujita Health University Babuntane Hospital, Nagoya, Japan
| | - Kyosuke Miyatani
- Department of Neurosurgery, Fujita Health University Babuntane Hospital, Nagoya, Japan
| | - Daijiro Kojima
- Department of Neurosurgery, Fujita Health University Babuntane Hospital, Nagoya, Japan
| | - Yoko Kato
- Department of Neurosurgery, Fujita Health University Babuntane Hospital, Nagoya, Japan
| |
Collapse
|
20
|
Rajagopal T, Seshachalam A, Rathnam KK, Jothi A, Viswanathan S, Talluri S, Dunna NR. DNA repair genes hOGG1, XRCC1 and ERCC2 polymorphisms and their molecular mapping in breast cancer patients from India. Mol Biol Rep 2020; 47:5081-5090. [PMID: 32519309 DOI: 10.1007/s11033-020-05577-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 06/05/2020] [Indexed: 11/29/2022]
Abstract
Identification of modifier genes predisposing to breast cancer (BC) phenotype remains a significant challenge and varies with ethnicity. The genetic variability observed in DNA repair genes may modulate the cell's ability to repair the damaged DNA and hence, evaluation of genetic variants in crucial DNA damage repair genes is of clinical importance. We performed the present study to evaluate the role of ERCC2-Lys751Gln, hOGG1-Ser326Cys, and XRCC1-Arg399Gln gene polymorphisms on the risk of BC development and its molecular profile in Indian women. Three non-synonymous variants (rs13181, rs1052133, and rs25487) were genotyped in 464 BC patients and 450 healthy controls. Logistic regression was employed to evaluate the association of genotypes with BC risk. Also, in silico analysis was carried out to map the Arg399Gln variant on the BRCT1 domain of XRCC1 protein. XRCC1 Gln/Gln genotype frequency was significantly elevated in BC patients [odd ratio (OR) = 1.73; 95% confidence interval (CI) = 1.13-2.65]. No significant association was observed between hOGG1-Ser326Cys and ERCC2-Lys751Gln variants and BC risk. Subgroup analysis revealed that ERCC2-Lys751Gln and XRCC1-Arg399Gln variants contributed towards tumor progression. A positive interaction between the investigated SNPs and BC was revealed by MDR analysis. Arg399Gln variant resulted in a change in the surface charge of XRCC1 protein. The rs25487 variant of XRCC1 might be associated with an elevated risk of BC. Furthermore, we demonstrated that high order gene-gene interaction plays a significant role in BC etiology. Hence, understanding the impact of low penetrant gene polymorphisms might enable a better understanding of the genetic background of breast cancer.
Collapse
Affiliation(s)
- Taruna Rajagopal
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Arun Seshachalam
- Department of Medical and Paediatric Oncology, Dr. G.V.N Cancer Institute, Singarathope, Tiruchchirappalli, 620 008, India
| | - Krishna Kumar Rathnam
- Department of Hemato Oncology - Medical Oncology and Bone Marrow Transplantation, Meenakshi Mission Hospital & Research Centre, Madurai, 625 107, India
| | - Arunachalam Jothi
- Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Swarna Viswanathan
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Srikanth Talluri
- Dana Farber Cancer Institute, Boston, MA, 02215, USA.,Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | - Nageswara Rao Dunna
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India.
| |
Collapse
|
21
|
Rajagopal T, Talluri S, Akshaya R, Dunna NR. HOTAIR LncRNA: A novel oncogenic propellant in human cancer. Clin Chim Acta 2020; 503:1-18. [DOI: 10.1016/j.cca.2019.12.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 12/27/2019] [Accepted: 12/30/2019] [Indexed: 02/08/2023]
|
22
|
Talluri S, Vaddamanu SK, Apparaju V, Vyas R, Ahuja S, Kanji MA. Evaluating cortico-cancellous ratio using virtual implant planning and its relation with immediate and long-term stability of a dental implant- A CBCT-assisted prospective observational clinical study. Niger J Clin Pract 2019; 22:982-987. [PMID: 31293265 DOI: 10.4103/njcp.njcp_22_19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Primary and long-term implant stabilities are crucial in predicting the success of dental implants. We aimed to evaluate corticocancellous ratio (CCR) around virtual implant using cone beam computed tomography (CT) and assess its relationship with immediate and long-term stability of the implants placed. MATERIALS AND METHODS A total of 135 image records of posterior mandibular implant sites planned for dental implant were included in our study. CCR was calculated using CT images and implants were placed after stent preparation. Implant stability was calculated immediately, 4 months later, and 2 years later. RESULTS Pearson's correlation test showed a significant correlation (P and lt; 0.001) between CCR and implant stability. ANOVA and post-hoc Tukey tests showed a significant difference in implant stability between groups with different CCRs at all follow-up timepoints. No significant difference was found between mean implant stability quotient values for low CCR at 2-year follow-up and high CCR immediately after implant placement. CONCLUSIONS Implant stability is improved with greater CCR. Cortical bone seems to be crucial factor for immediate and long-term stability of a dental implant. Virtual planning using CT can assess implant stability. Further histological studies are required to confirm the relation between CCR and implant stability. The escalating demand of the implant treatment in the dental practice necessitates measuring the several predictors of procedure success. This study introduces a novel predictor (CCR) around virtual implant for detecting the immediate and long-term stability of a dental implant.
Collapse
Affiliation(s)
- S Talluri
- Department of Periodontology and Oral Implantology, Rambabu Dental Hospital, Ongole, India
| | - S K Vaddamanu
- Department of Dental Technology, College of Applied Medical Science, King Khalid University, Abha, Saudi Arabia
| | - V Apparaju
- Department of Periodontics, Dr. Vijay's Multi Speciality Dental Care, Implant and Laser Center, Bangalore, India
| | - R Vyas
- Department of Dental Technology, College of Applied Medical Science, King Khalid University, Abha, Saudi Arabia
| | - S Ahuja
- Department of Occupational Health and Safety Management, Lambton College of Applied Arts and Technology, Scarborough, Toronto, Ontario, Canada
| | - M A Kanji
- Department of Dental Technology, College of Applied Medical Science, King Khalid University, Abha, Saudi Arabia
| |
Collapse
|
23
|
Nandi B, Talluri S, Kumar S, Yenumula C, Gold JS, Prabhala R, Munshi NC, Shammas MA. The roles of homologous recombination and the immune system in the genomic evolution of cancer. ACTA ACUST UNITED AC 2018; 5. [PMID: 30873294 PMCID: PMC6411307 DOI: 10.15761/jts.1000282] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A variety of factors, whether extracellular (mutagens/carcinogens and viruses in the environment, chronic inflammation and radiation associated with the environment and/or electronic devices/machines) and/or intracellular (oxidative metabolites of food, oxidative stress due to inflammation, acid production, replication stress, DNA replication/repair errors, and certain hormones, cytokines, growth factors), pose a constant threat to the genomic integrity of a living cell. However, in the normal cellular environment multiple biological pathways including DNA repair, cell cycle, apoptosis and the immune system work in a precise, regulated (tightly controlled), timely and concerted manner to ensure genomic integrity, stability and proper functioning of a cell. If damage to DNA takes place, it is efficiently and accurately repaired by the DNA repair systems. Homologous recombination (HR) which utilizes either a homologous chromosome (in G1 phase) or a sister chromatid (in G2) as a template to repair the damage, is known to be the most precise repair system. HR in G2 which utilizes a sister chromatid as a template is also called an error free repair system. If DNA damage in a cell is so extensive that it overwhelms the repair system/s, the cell is eliminated by apoptosis. Thus, multiple pathways ensure that genome of a cell is intact and stable. However, constant exposure to DNA damage and/or dysregulation of DNA repair mechanism/s poses a risk of mutation and cancer. Oncogenesis, which seems to be a multistep process, is associated with acquisition of a number of genomic changes that enable a normal cell to progress from benign to malignant transformation. Transformed/cancer cells are recognized and killed by the immune system. However, the ongoing acquisition of new genomic changes enables cancer cells to survive/escape immune attack, evolve into a more aggressive phenotype, and eventually develop resistance to therapy. Although DNA repair (especially the HR) and the immune system play unique roles in preserving genomic integrity of a cell, they can also contribute to DNA damage, genomic instability and oncogenesis. The purpose of this article is to highlight the roles of DNA repair (especially HR) and the immune system in genomic evolution, with special focus on gastrointestinal cancer.
Collapse
Affiliation(s)
- B Nandi
- Harvard Medical School and Brigham and Women's Hospital, USA.,Researh Services, VA Healthcare System, West Roxbury, MA, USA
| | - S Talluri
- Harvard (Dana Farber) Cancer Institute, Boston, MA, USA.,Researh Services, VA Healthcare System, West Roxbury, MA, USA
| | - S Kumar
- Harvard (Dana Farber) Cancer Institute, Boston, MA, USA.,Harvard Medical School and Brigham and Women's Hospital, USA
| | - C Yenumula
- Harvard Medical School and Brigham and Women's Hospital, USA.,Researh Services, VA Healthcare System, West Roxbury, MA, USA
| | - J S Gold
- Harvard Medical School and Brigham and Women's Hospital, USA.,Surgery Services, VA Healthcare System, West Roxbury, MA, USA
| | - R Prabhala
- Harvard (Dana Farber) Cancer Institute, Boston, MA, USA.,Researh Services, VA Healthcare System, West Roxbury, MA, USA
| | - N C Munshi
- Harvard (Dana Farber) Cancer Institute, Boston, MA, USA.,Harvard Medical School and Brigham and Women's Hospital, USA.,Researh Services, VA Healthcare System, West Roxbury, MA, USA
| | - M A Shammas
- Harvard (Dana Farber) Cancer Institute, Boston, MA, USA.,Researh Services, VA Healthcare System, West Roxbury, MA, USA
| |
Collapse
|
24
|
Khan S, Talluri S, Riaz IB, Riaz H, Kaluski E. P6077A network meta-analysis of new oral anticoagulants based antithrombotic regimens. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.p6077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- S Khan
- Guthrie Clinic, Internal Medicine, Robert Packer Hospital, Sayre, PA, United States of America
| | - S Talluri
- Guthrie Clinic, Internal Medicine, Robert Packer Hospital, Sayre, PA, United States of America
| | - I B Riaz
- Mayo Clinic, Rochester, United States of America
| | - H Riaz
- Cleveland Clinic Foundation, Cleveland, United States of America
| | - E Kaluski
- Guthrie Clinic, Cardiology, Sayre, PA, United States of America
| |
Collapse
|
25
|
Qasaimeh MA, Wu YC, Bose S, Menachery A, Talluri S, Gonzalez G, Fulciniti M, Karp JM, Prabhala RH, Karnik R. Isolation of Circulating Plasma Cells in Multiple Myeloma Using CD138 Antibody-Based Capture in a Microfluidic Device. Sci Rep 2017; 7:45681. [PMID: 28374831 PMCID: PMC5379479 DOI: 10.1038/srep45681] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 03/02/2017] [Indexed: 12/15/2022] Open
Abstract
The necessity for bone marrow aspiration and the lack of highly sensitive assays to detect residual disease present challenges for effective management of multiple myeloma (MM), a plasma cell cancer. We show that a microfluidic cell capture based on CD138 antigen, which is highly expressed on plasma cells, permits quantitation of rare circulating plasma cells (CPCs) in blood and subsequent fluorescence-based assays. The microfluidic device is based on a herringbone channel design, and exhibits an estimated cell capture efficiency of ~40–70%, permitting detection of <10 CPCs/mL using 1-mL sample volumes, which is difficult using existing techniques. In bone marrow samples, the microfluidic-based plasma cell counts exhibited excellent correlation with flow cytometry analysis. In peripheral blood samples, the device detected a baseline of 2–5 CD138+ cells/mL in healthy donor blood, with significantly higher numbers in blood samples of MM patients in remission (20–24 CD138+ cells/mL), and yet higher numbers in MM patients exhibiting disease (45–184 CD138+ cells/mL). Analysis of CPCs isolated using the device was consistent with serum immunoglobulin assays that are commonly used in MM diagnostics. These results indicate the potential of CD138-based microfluidic CPC capture as a useful ‘liquid biopsy’ that may complement or partially replace bone marrow aspiration.
Collapse
Affiliation(s)
- Mohammad A Qasaimeh
- Division of Engineering, New York University Abu Dhabi, Abu Dhabi, UAE.,Mechanical and Aerospace Engineering Department, New York University, Brooklyn, NY 11201, USA.,Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Yichao C Wu
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Suman Bose
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Anoop Menachery
- Division of Engineering, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Srikanth Talluri
- VA Boston Healthcare System, Boston, MA, USA.,Dana-Farber Cancer Institute, Boston, MA, USA
| | | | | | - Jeffrey M Karp
- Division of BioEngineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Harvard Stem Cell Institute, Harvard-MIT Division of Health Sciences and Technology, 65 Landsdowne St., Cambridge, MA 02139, USA
| | - Rao H Prabhala
- VA Boston Healthcare System, Boston, MA, USA.,Dana-Farber Cancer Institute, Boston, MA, USA.,Brigham and Women's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Rohit Karnik
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| |
Collapse
|
26
|
Thwaites MJ, Cecchini MJ, Talluri S, Passos DT, Carnevale J, Dick FA. Multiple molecular interactions redundantly contribute to RB-mediated cell cycle control. Cell Div 2017; 12:3. [PMID: 28293272 PMCID: PMC5348811 DOI: 10.1186/s13008-017-0029-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 02/28/2017] [Indexed: 02/07/2023] Open
Abstract
Background The G1-S phase transition is critical to maintaining proliferative control and preventing carcinogenesis. The retinoblastoma tumor suppressor is a key regulator of this step in the cell cycle. Results Here we use a structure–function approach to evaluate the contributions of multiple protein interaction surfaces on pRB towards cell cycle regulation. SAOS2 cell cycle arrest assays showed that disruption of three separate binding surfaces were necessary to inhibit pRB-mediated cell cycle control. Surprisingly, mutation of some interaction surfaces had no effect on their own. Rather, they only contributed to cell cycle arrest in the absence of other pRB dependent arrest functions. Specifically, our data shows that pRB–E2F interactions are competitive with pRB–CDH1 interactions, implying that interchangeable growth arrest functions underlie pRB’s ability to block proliferation. Additionally, disruption of similar cell cycle control mechanisms in genetically modified mutant mice results in ectopic DNA synthesis in the liver. Conclusions Our work demonstrates that pRB utilizes a network of mechanisms to prevent cell cycle entry. This has important implications for the use of new CDK4/6 inhibitors that aim to activate this proliferative control network.
Collapse
Affiliation(s)
- Michael J Thwaites
- London Regional Cancer Program, London, Canada.,Department of Biochemistry, Western University, London, ON Canada
| | - Matthew J Cecchini
- London Regional Cancer Program, London, Canada.,Department of Biochemistry, Western University, London, ON Canada
| | - Srikanth Talluri
- London Regional Cancer Program, London, Canada.,Department of Biochemistry, Western University, London, ON Canada
| | - Daniel T Passos
- London Regional Cancer Program, London, Canada.,Department of Biochemistry, Western University, London, ON Canada
| | - Jasmyne Carnevale
- London Regional Cancer Program, London, Canada.,Department of Biochemistry, Western University, London, ON Canada
| | - Frederick A Dick
- London Regional Cancer Program, London, Canada.,Children's Health Research Institute, London, Canada.,Department of Biochemistry, Western University, London, ON Canada
| |
Collapse
|
27
|
Zarghami N, Jensen MD, Talluri S, Foster PJ, Chambers AF, Dick FA, Wong E. Technical Note: Immunohistochemical evaluation of mouse brain irradiation targeting accuracy with 3D-printed immobilization device. Med Phys 2016; 42:6507-13. [PMID: 26520740 DOI: 10.1118/1.4933200] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Small animal immobilization devices facilitate positioning of animals for reproducible imaging and accurate focal radiation therapy. In this study, the authors demonstrate the use of three-dimensional (3D) printing technology to fabricate a custom-designed mouse head restraint. The authors evaluate the accuracy of this device for the purpose of mouse brain irradiation. METHODS A mouse head holder was designed for a microCT couch using cad software and printed in an acrylic based material. Ten mice received half-brain radiation while positioned in the 3D-printed head holder. Animal placement was achieved using on-board image guidance and computerized asymmetric collimators. To evaluate the precision of beam localization for half-brain irradiation, mice were sacrificed approximately 30 min after treatment and brain sections were stained for γ-H2AX, a marker for DNA breaks. The distance and angle of the γ-H2AX radiation beam border to longitudinal fissure were measured on histological samples. Animals were monitored for any possible trauma from the device. RESULTS Visualization of the radiation beam on ex vivo brain sections with γ-H2AX immunohistochemical staining showed a sharp radiation field within the tissue. Measurements showed a mean irradiation targeting error of 0.14±0.09 mm (standard deviation). Rotation between the beam axis and mouse head was 1.2°±1.0° (standard deviation). The immobilization device was easily adjusted to accommodate different sizes of mice. No signs of trauma to the mice were observed from the use of tooth block and ear bars. CONCLUSIONS The authors designed and built a novel 3D-printed mouse head holder with many desired features for accurate and reproducible radiation targeting. The 3D printing technology was found to be practical and economical for producing a small animal imaging and radiation restraint device and allows for customization for study specific needs.
Collapse
Affiliation(s)
- Niloufar Zarghami
- Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada
| | - Michael D Jensen
- Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada
| | - Srikanth Talluri
- Department of Biochemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada and London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9, Canada
| | - Paula J Foster
- Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8, Canada and Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada
| | - Ann F Chambers
- Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada; Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada; and London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9, Canada
| | - Frederick A Dick
- Department of Biochemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada and London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9, Canada
| | - Eugene Wong
- Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada; Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada; and London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9, Canada
| |
Collapse
|
28
|
Coschi CH, Ishak CA, Gallo D, Marshall A, Talluri S, Wang J, Cecchini MJ, Martens AL, Percy V, Welch I, Boutros PC, Brown GW, Dick FA. Haploinsufficiency of an RB-E2F1-Condensin II complex leads to aberrant replication and aneuploidy. Cancer Discov 2014; 4:840-53. [PMID: 24740996 DOI: 10.1158/2159-8290.cd-14-0215] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
UNLABELLED Genome instability is a characteristic of malignant cells; however, evidence for its contribution to tumorigenesis has been enigmatic. In this study, we demonstrate that the retinoblastoma protein, E2F1, and Condensin II localize to discrete genomic locations including major satellite repeats at pericentromeres. In the absence of this complex, aberrant replication ensues followed by defective chromosome segregation in mitosis. Surprisingly, loss of even one copy of the retinoblastoma gene reduced recruitment of Condensin II to pericentromeres and caused this phenotype. Using cancer genome data and gene-targeted mice, we demonstrate that mutation of one copy of RB1 is associated with chromosome copy-number variation in cancer. Our study connects DNA replication and chromosome structure defects with aneuploidy through a dosage-sensitive complex at pericentromeric repeats. SIGNIFICANCE Genome instability is inherent to most cancers and is the basis for selective killing of cancer cells by genotoxic therapeutics. In this report, we demonstrate that instability can be caused by loss of a single allele of the retinoblastoma gene that prevents proper replication and condensation of pericentromeric chromosomal regions, leading to elevated levels of aneuploidy in cancer.
Collapse
Affiliation(s)
- Courtney H Coschi
- Authors' Affiliations:London Regional Cancer Program; Department of Biochemistry, and
| | - Charles A Ishak
- Authors' Affiliations:London Regional Cancer Program; Department of Biochemistry, and
| | - David Gallo
- Biochemistry, Donnelly Centre, University of Toronto; and
| | - Aren Marshall
- Authors' Affiliations:London Regional Cancer Program; Department of Biochemistry, and
| | - Srikanth Talluri
- Authors' Affiliations:London Regional Cancer Program; Department of Biochemistry, and
| | - Jianxin Wang
- Informatics and Biocomputing Program, Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Matthew J Cecchini
- Authors' Affiliations:London Regional Cancer Program; Department of Biochemistry, and
| | - Alison L Martens
- Authors' Affiliations:London Regional Cancer Program; Department of Biochemistry, and
| | - Vanessa Percy
- Authors' Affiliations:London Regional Cancer Program
| | - Ian Welch
- Veterinary Services, Western University, London; Departments of
| | - Paul C Boutros
- Medical Biophysics, and Pharmacology and Toxicology, Informatics and Biocomputing Program, Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Grant W Brown
- Biochemistry, Donnelly Centre, University of Toronto; and
| | - Frederick A Dick
- Authors' Affiliations:London Regional Cancer Program; Children's Health Research Institute; Department of Biochemistry, and
| |
Collapse
|
29
|
Talluri S, Dick FA. The retinoblastoma protein and PML collaborate to organize heterochromatin and silence E2F-responsive genes during senescence. Cell Cycle 2013; 13:641-51. [PMID: 24351540 DOI: 10.4161/cc.27527] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cellular senescence is characterized by silencing of genes involved in DNA replication and cell cycle progression. Stable repression is crucial for preventing inappropriate DNA synthesis and the maintenance of a prolonged senescent state. Many of these genes are targets for E2F transcription factors. The pRB pathway plays a major role in senescence by directly repressing E2Fs and also by regulating chromatin at the promoters of E2F target genes using its LXCXE cleft-dependent interactions. In this study, we sought to investigate the mechanisms by which pRB stably silences E2F target gene transcription during cellular senescence. We report that in mouse embryonic fibroblasts, endogenous promyelocytic leukemia protein (PML) associates with E2F target genes in a pRB LXCXE-dependent manner during HrasV12-induced senescence. Furthermore, using a PML-IV-induced senescence model, we show that the pRB LXCXE binding cleft is essential for PML association with gene promoters, silencing of E2F target genes, and stable cell cycle exit. Binding assays show that pRB can interact with PML specifically during senescence, suggesting that signaling events in senescence regulate assembly of PML and pRB to establish heterochromatin and create a permanent cell cycle arrest.
Collapse
Affiliation(s)
- Srikanth Talluri
- London Regional Cancer Program; Western University; London, Ontario, Canada; Department of Biochemistry; Western University; London, Ontario, Canada
| | - Frederick A Dick
- London Regional Cancer Program; Western University; London, Ontario, Canada; Department of Biochemistry; Western University; London, Ontario, Canada; Children's Health Research Institute; Western University; London, Ontario, Canada
| |
Collapse
|
30
|
Talluri S, Francis SM, Dick FA. Mutation of the LXCXE binding cleft of pRb facilitates transformation by ras in vitro but does not promote tumorigenesis in vivo. PLoS One 2013; 8:e72236. [PMID: 23936539 PMCID: PMC3735560 DOI: 10.1371/journal.pone.0072236] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 07/12/2013] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The Retinoblastoma protein (pRB) is a key tumor suppressor that is functionally inactivated in most cancers. pRB regulates the cell division cycle and cell cycle exit through protein-protein interactions mediated by its multiple binding interfaces. The LXCXE binding cleft region of pRB mediates interactions with cellular proteins that have chromatin regulatory functions. Chromatin regulation mediated by pRB is required for a stress responsive cell cycle arrest, including oncogene induced senescence. The in vivo role of chromatin regulation by pRB during senescence, and its relevance to cancer is not clear. METHODOLOGY/PRINCIPAL FINDINGS Using gene-targeted mice, uniquely defective for pRB mediated chromatin regulation, we investigated its role during transformation and tumor progression in response to activation of oncogenic ras. We report that the pRB(∆L) mutation confers susceptibility to escape from HrasV12 induced senescence and allows transformation in vitro, although these cells possess high levels of DNA damage. Intriguingly, LSL-Kras, Rb1 (∆L/∆L) mice show delayed lung tumor formation compared to controls. This is likely due to the increased apoptosis seen in the early hyperplastic lesions shortly following ras activation that inhibits tumor progression. Furthermore, DMBA treatment to induce sporadic ras mutations in other tissues also failed to reveal greater susceptibility to cancer in Rb1 (∆L/∆L) mice. CONCLUSIONS/SIGNIFICANCE Our data suggests that chromatin regulation by pRB can function to limit proliferation, but its loss fails to contribute to cancer susceptibility in ras driven tumor models because of elevated levels of DNA damage and apoptosis.
Collapse
Affiliation(s)
- Srikanth Talluri
- London Regional Cancer Program, Western University, London, Ontario, Canada
- Department of Biochemistry, Western University, London, Ontario, Canada
| | - Sarah M. Francis
- London Regional Cancer Program, Western University, London, Ontario, Canada
- Department of Biochemistry, Western University, London, Ontario, Canada
| | - Frederick A. Dick
- London Regional Cancer Program, Western University, London, Ontario, Canada
- Children’s Health Research Institute, Western University, London, Ontario, Canada
- Department of Biochemistry, Western University, London, Ontario, Canada
- * E-mail:
| |
Collapse
|
31
|
Abstract
Commitment to divide is one of the most crucial steps in the mammalian cell division cycle. It is critical for tissue and organismal homeostasis, and consequently is highly regulated. The vast majority of cancers evade proliferative control, further emphasizing the importance of the commitment step in cell cycle regulation. The Retinoblastoma (RB) tumor suppressor pathway regulates this decision-making step. Since being the subject of Knudson's 'two hit hypothesis', there has been considerable interest in understanding pRB's role in cancer. It is best known for repressing E2F dependent transcription of cell cycle genes. However, pRB's role in controlling chromatin structure is expanding and bringing it into new regulatory paradigms. In this review we discuss pRB function through protein-protein interactions, at the level of transcriptional regulation of individual promoters and in organizing higher order chromatin domains.
Collapse
Affiliation(s)
- Srikanth Talluri
- London Regional Cancer Program; Western University; London, ON Canada
- Department of Biochemistry; Western University; London, ON Canada
| | - Frederick A. Dick
- London Regional Cancer Program; Western University; London, ON Canada
- Department of Biochemistry; Western University; London, ON Canada
- Children’s Health Research Institute; Western University; London, ON Canada
| |
Collapse
|
32
|
Talluri S, Kakarala R, Karedan T, Kakarala M. Male breast carcinoma in United States: Survival rate and determinants of prognosis. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.27_suppl.32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
32 Background: Male breast cancer (MBC) is rare and accounts for less than 1% of all cancers in men. It causes significant morbidity and mortality due to late diagnosis. The primary objective of our study is to update information about the receptor status, pathology, survival rates, and prognostic factors for MBC. Our secondary objective is to determine racial differences in survival of MBC and compare tumor characteristics with female breast cancer (FBC) patients. Methods: We analyzed a retrospective cohort of breast cancer patients included in National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) from 1990 to 2007. Differences between patient and disease characteristics at the time of diagnosis among MBC and FBC patients were compared using chi-square test. Overall survival was estimated using Kaplan-Meier method. Cox proportional hazards regression model was used to determine the independent variables that affect survival. Results: We included 2,475 men and 393,259 women with breast cancer in our analysis. Median age at diagnosis was higher in men compared to women (67 vs 61years). Men had more frequent lymph node involvement (32% vs. 22%), ER positivity (66% vs. 57%) and PR positivity (57% vs. 49%) breast cancer than women (P<0.001). Overall median survival in MBC was 9 years, 5-year survival was 63% and 10-year survival was 43%. Increased age, larger tumor size, higher grade, lymph node involvement, ER and PR negative status were significantly associated with decreased survival in univariate analysis (P <0.05). In multivariate analysis, age > 65 years at the time of diagnosis, larger tumor size, positive lymph node status, ER negative status and poorly differentiated grade were associated with decreased survival (P <0.02). However PR status was not a significant predictor of survival. The median survival in African American males was lower as compared to Caucasians (7.08 vs. 9.2 yrs.) (P=0.02). Conclusions: Male breast cancer differs from female breast cancer in important biological characteristics with a higher age at diagnosis and frequent lymph node involvement. Age greater than 65 years, tumor size, grade, lymph node involvement and ER status of the tumor are independent predictors of survival in MBC.
Collapse
Affiliation(s)
- S. Talluri
- McLaren Regional Medical Center, Flint, MI; 4193 MED ED - INTERNAL MED, Flint, MI; University of Michigan Health System, Ann Arbor, MI
| | - R. Kakarala
- McLaren Regional Medical Center, Flint, MI; 4193 MED ED - INTERNAL MED, Flint, MI; University of Michigan Health System, Ann Arbor, MI
| | - T. Karedan
- McLaren Regional Medical Center, Flint, MI; 4193 MED ED - INTERNAL MED, Flint, MI; University of Michigan Health System, Ann Arbor, MI
| | - M. Kakarala
- McLaren Regional Medical Center, Flint, MI; 4193 MED ED - INTERNAL MED, Flint, MI; University of Michigan Health System, Ann Arbor, MI
| |
Collapse
|
33
|
Talluri S, Isaac CE, Ahmad M, Henley SA, Francis SM, Martens AL, Bremner R, Dick FA. A G1 checkpoint mediated by the retinoblastoma protein that is dispensable in terminal differentiation but essential for senescence. Mol Cell Biol 2010; 30:948-60. [PMID: 20008551 PMCID: PMC2815577 DOI: 10.1128/mcb.01168-09] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 09/23/2009] [Accepted: 12/07/2009] [Indexed: 11/20/2022] Open
Abstract
Terminally differentiated cell types are needed to live and function in a postmitotic state for a lifetime. Cellular senescence is another type of permanent arrest that blocks the proliferation of cells in response to genotoxic stress. Here we show that the retinoblastoma protein (pRB) uses a mechanism to block DNA replication in senescence that is distinct from its role in permanent cell cycle exit associated with terminal differentiation. Our work demonstrates that a subtle mutation in pRB that cripples its ability to interact with chromatin regulators impairs heterochromatinization and repression of E2F-responsive promoters during senescence. In contrast, terminally differentiated nerve and muscle cells bearing the same mutation fully exit the cell cycle and block E2F-responsive gene expression by a different mechanism. Remarkably, this reveals that pRB recruits chromatin regulators primarily to engage a stress-responsive G(1) arrest program.
Collapse
Affiliation(s)
- Srikanth Talluri
- London Regional Cancer Program, Children's Health Research Institute, Department of Biochemistry, University of Western Ontario, London, Ontario, Canada, Genetics and Development Division, Toronto Western Research Institute, Department of Ophthalmology and Visual Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Christian E. Isaac
- London Regional Cancer Program, Children's Health Research Institute, Department of Biochemistry, University of Western Ontario, London, Ontario, Canada, Genetics and Development Division, Toronto Western Research Institute, Department of Ophthalmology and Visual Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Mohammad Ahmad
- London Regional Cancer Program, Children's Health Research Institute, Department of Biochemistry, University of Western Ontario, London, Ontario, Canada, Genetics and Development Division, Toronto Western Research Institute, Department of Ophthalmology and Visual Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Shauna A. Henley
- London Regional Cancer Program, Children's Health Research Institute, Department of Biochemistry, University of Western Ontario, London, Ontario, Canada, Genetics and Development Division, Toronto Western Research Institute, Department of Ophthalmology and Visual Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Sarah M. Francis
- London Regional Cancer Program, Children's Health Research Institute, Department of Biochemistry, University of Western Ontario, London, Ontario, Canada, Genetics and Development Division, Toronto Western Research Institute, Department of Ophthalmology and Visual Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Alison L. Martens
- London Regional Cancer Program, Children's Health Research Institute, Department of Biochemistry, University of Western Ontario, London, Ontario, Canada, Genetics and Development Division, Toronto Western Research Institute, Department of Ophthalmology and Visual Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Rod Bremner
- London Regional Cancer Program, Children's Health Research Institute, Department of Biochemistry, University of Western Ontario, London, Ontario, Canada, Genetics and Development Division, Toronto Western Research Institute, Department of Ophthalmology and Visual Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Frederick A. Dick
- London Regional Cancer Program, Children's Health Research Institute, Department of Biochemistry, University of Western Ontario, London, Ontario, Canada, Genetics and Development Division, Toronto Western Research Institute, Department of Ophthalmology and Visual Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
34
|
Talluri S, Montelione GT, Van Duyne G, Piela L, Clardy J, Scheraga HA. Conformational properties of 2,4-methanoproline (2-carboxy-2,4-methanopyrrolidine) in peptides: evidence for 2,4-methanopyrrolidine asymmetry based on solid-state x-ray crystallography, proton NMR in aqueous solution, and CNDO/2 conformational energy calculations. J Am Chem Soc 2002. [DOI: 10.1021/ja00249a008] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
35
|
Talluri S, Falcomer CM, Scheraga HA. Energetic and structural basis for the preferential formation of the native disulfide loop involving Cys-65 and Cys-72 in synthetic peptide fragments derived from the sequence of ribonuclease A. J Am Chem Soc 2002. [DOI: 10.1021/ja00061a001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
36
|
Falcomer CM, Meinwald YC, Choudhary I, Talluri S, Milburn PJ, Clardy J, Scheraga HA. Chain reversals in model peptides: studies of cystine-containing cyclic peptides. 3. Conformational free energies of cyclization of tetrapeptides of sequence Ac-Cys-Pro-X-Cys-NHMe. J Am Chem Soc 2002. [DOI: 10.1021/ja00037a003] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
37
|
Affiliation(s)
- S Talluri
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts, 02115, USA
| | | |
Collapse
|
38
|
Liwo A, Tempczyk A, Ołdziej S, Shenderovich MD, Hruby VJ, Talluri S, Ciarkowski J, Kasprzykowski F, Lankiewicz L, Grzonka Z. Exploration of the conformational space of oxytocin and arginine-vasopressin using the electrostatically driven Monte Carlo and molecular dynamics methods. Biopolymers 1996; 38:157-75. [PMID: 8589250 DOI: 10.1002/(sici)1097-0282(199602)38:2<157::aid-bip3>3.0.co;2-u] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Conformational analysis of the neurohypophyseal hormones oxytocin (OT) and arginine-vasopressin (AVP) has been carried out using two different computational approaches and three force fields, namely by the Electrostatically Driven Monte Carlo (EDMC) method, with the Empirical Conformational Energy Program for Peptides (ECEPP/3) force field or with the ECEPP/3 force field plus a hydration-shell model, and by simulated-annealing molecular dynamics with the Consistent Valence Force Field (CVFF). The low-energy conformations obtained for both hormones were classified using the minimal-tree clustering algorithm and characterized according to the locations of beta-turns in the cyclic moieties. Calculations with the CVFF force field located conformations with a beta-turn at residues 3 and 4 as the lowest energy ones both for OT and for AVP. In the ECEPP/3 force field the lowest energy conformation of OT contained a beta-turn at residues 2 and 3, conformations with this location of the turn being higher in energy for AVP. The latter difference can be attributed to the difference in the size of the side chain in position 3 of the sequences: the bulkier phenylalanine residue of AVP in combination with the bulky Tyr2 residue hinders the formation of a turn at residues 2 and 3. Conformations of OT and AVP with a turn at residues 3,4 were in the best agreement with the x-ray structures of deaminooxytocin and pressinoic acid (the cyclic moiety of vasopressin), respectively, and with the nmr-derived distance constraints. Generally, the low-energy conformations obtained with the hydration-shell model were in a better agreement with the experimental data than the conformations calculated in vacuo. It was found, however, that the obtained low-energy conformations do not satisfy all of the nmr-derived distance constraints and the nuclear Overhauser effect pattern observed in nmr studies can be fully explained only by assuming a dynamic equilibrium between conformations with beta-turns at residues 2,3, 3,4, and 4,5. The low-energy structures of OT with a beta-turn at residues 2,3 have the disulfide ring conformations close to the model proposed recently for a potent bicyclic antagonist of OT [M. D. Shenderovich et al. (1994) Polish Journal of Chemistry, Vol. 25, pp. 921-927], although the native hormone differs from the bicyclic analogue by the conformation of the C-terminal tripeptide. This finding confirms the hypothesis of different receptor-bound conformations of agonists and antagonists of OT.
Collapse
Affiliation(s)
- A Liwo
- Department of Chemistry, University of Gdańsk, Poland
| | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Talluri S, Bhatt A, Smith DP. Identification of a Drosophila G protein alpha subunit (dGq alpha-3) expressed in chemosensory cells and central neurons. Proc Natl Acad Sci U S A 1995; 92:11475-9. [PMID: 8524786 PMCID: PMC40424 DOI: 10.1073/pnas.92.25.11475] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have identified another Drosophila GTP-binding protein (G protein) alpha subunit, dGq alpha-3. Transcripts encoding dGq alpha-3 are derived from alternative splicing of the dGq alpha locus previously shown to encode two visual-system-specific transcripts [Lee, Y.-J., Dobbs, M.B., Verardi, M.L. & Hyde, D.R. (1990) Neuron 5, 889-898]. Immunolocalization studies using dGq alpha-3 isoform-specific antibodies and LacZ fusion genes show that dGq alpha-3 is expressed in chemosensory cells of the olfactory and taste structures, including a subset of olfactory and gustatory neurons, and in cells of the central nervous system, including neurons in the lamina ganglionaris. These data are consistent with a variety of roles for dGq alpha-3, including mediating a subset of olfactory and gustatory responses in Drosophila, and supports the idea that some chemosensory responses use G protein-coupled receptors and the second messenger inositol 1,4,5-trisphosphate.
Collapse
Affiliation(s)
- S Talluri
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas 75235, USA
| | | | | |
Collapse
|
40
|
Abstract
BACKGROUND The pleckstrin homology (PH) domain, which is approximately 100 amino acids long, has been found in about 70 proteins involved in signal transduction and cytoskeletal function, a frequency comparable to SH2 (src homology 2) and SH3 domains. PH domains have been shown to bind the beta gamma-subunits of G-proteins and phosphatidylinositol 4,5-bisphosphate (PIP2). It is conceivable that the PH domain of beta-spectrin plays a part in the association of spectrin with the plasma membrane of cells. RESULTS We have solved the solution structure of the 122-residue PH domain of Drosophila beta-spectrin. The overall fold consists of two antiparallel beta-sheets packing against each other at an angle of approximately 60 degrees to form a beta-sandwich, a two-turn alpha-helix unique to spectrin PH domains, and a four-turn C-terminal alpha-helix. One of the major insertions in beta-spectrin PH domains forms a long, basic surface loop and appears to undergo slow conformational exchange in solution. This loop shows big spectral changes upon addition of D-myo-inositol 1,4,5-trisphosphate (IP3). CONCLUSIONS We propose that the groove at the outer surface of the second beta-sheet is an important site of association with other proteins. This site and the possible lipid-binding site can serve to localize the spectrin network under the plasma membrane. More generally, it has to be considered that the common fold observed for the PH domain structures solved so far does not necessarily mean that all PH domains have similar functions. In fact, the residues constituting potential binding sites for ligands or other proteins are only slightly conserved between different PH domains.
Collapse
Affiliation(s)
- P Zhang
- Committee on Higher Degrees in Biophysics, Harvard University, Boston, MA 02115, USA
| | | | | | | | | |
Collapse
|
41
|
Talluri S, Rothwarf DM, Scheraga HA. Structural characterization of a three-disulfide intermediate of ribonuclease A involved in both the folding and unfolding pathways. Biochemistry 1994; 33:10437-49. [PMID: 8068682 DOI: 10.1021/bi00200a027] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Earlier studies of the unfolding pathway of native bovine pancreatic ribonuclease A (using dithiothreitol as the reducing agent) revealed that the three-disulfide species lacking the disulfide bond between cysteine 65 and cysteine 72 is the most highly populated intermediate [Rothwarf & Scheraga (1991) J. Am. Chem. Soc. 113, 6293-6294]. This unfolding intermediate is referred to as des-[65-72]-RNase A. In order to determine the role of des-[65-72]-RNase A, i.e. of the 65-72 disulfide bond, in the structural folding/unfolding processes of RNase A, the stability and structure of this unfolding intermediate were determined by examining its thermal transition curve and by using two- and three-dimensional homonuclear 1H NMR spectroscopy. The midpoint of the thermal transition of des-[65-72]-RNase A was found to be 17.8 degrees C lower than that of native RNase A. A set of conformations that are consistent with the NMR-derived constraints was obtained by minimizing, first, a variable-target function and, then, the conformational energy. These conformations exhibit a well-defined structure that is very similar to that of native ribonuclease A in regions where the native protein has a regular backbone structure such as a beta-sheet or a helix. Some of the loop regions of the several computed structures exhibit large deviations from each other as well as from native ribonuclease A. However, these results indicate that des-[65-72]-RNase A has a close structural similarity to RNase A in all regions with the only major differences occurring in a loop region comprising residues 60-72. This led to the conclusion that, in reduction pathways that include des-[65-72]-RNase A (at 25 degrees C, pH 8.0), the rate-determining step corresponds to a partial unfolding event in one region of the protein and not to a global conformational unfolding process. The results further suggest that, in the regeneration pathways involving des-[65-72]-RNase A, the loop region from 60 to 72 is the last to fold.
Collapse
Affiliation(s)
- S Talluri
- Baker Laboratory of Chemistry, Cornell University, Ithaca, New York 14853-1301
| | | | | |
Collapse
|
42
|
Abstract
The H/D exchange behavior of RNase A at pH 2.5 at a number of temperatures spanning the thermal transition region has been examined by NMR spectroscopy. The amide proton of V116 has a slow rate of H/D exchange even at temperatures above the midpoint of the thermal transition. The H/D exchange behavior of the peptide corresponding to residues 105-124 of RNase A and the peptide corresponding to residues 115-117 is compared with that of RNase A, showing that folding/unfolding cannot be described by a two-state model, and that both short- and long-range interactions are responsible for the slow rate of H/D exchange.
Collapse
Affiliation(s)
- S Talluri
- Baker Laboratory of Chemistry, Cornell University, Ithaca, NY 14853-1301
| | | |
Collapse
|
43
|
|