Alpa Sidhu€‡, Justin R. Miller€‡, Ashootosh Tripathi¶, Danielle M. Garshott€, Amy L. Brownell€, Daniel J. Chiego∑, Carl Arevang¶, Qinghua Zeng€, Leah C. Jackson€, Shelby A. Bechler€, Michael U. Calla- ghan€, George H. YooÖ, Seema Sethiñ, Ho-Sheng LinÖ, Joseph H. Callaghan§, Giselle Tamayo- CastilloØ, David H. Sherman¶, *, Randal J. KaufmanΩ, * and Andrew M. Fribley€,Ö, ≠,* € Carmen and Ann Adams Department of Pediatrics, Wayne State University School of Medicine, Detroit, MI 48201 ¶ Life Sciences Institute and Departments of Medicinal Chemistry, Chemistry, Microbiology & Immunology, University of Michigan, Ann Arbor, MI 48109 ∑ Cariology, Restorative Sciences and Endodontics, University of Michigan School of Dentistry, Ann Arbor, MI 48109 Ö Department of Otolaryngology, Wayne State University and Karmanos Cancer Institute, Detroit, MI 48201 ñ Department of Pathology, Wayne State University and Karmanos Cancer Institute, Detroit, MI 48201 § School of Business Administration, Oakland University, Rochester, MI 48309 ØInstituto Nacional de Biodiversidad, 3100-Heredia, CIPRONA-Escuela de Química, Universidad de Costa Rica Ω Degenerative Disease Research Program, Center for Cancer Research, Sanford|Burnham Medical Research Institute, La Jolla, CA 92037 ≠ Developmental Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, MI 48201 ‡ These authors contributed equally Contents: Page: Experimental Procedures 2 - 3 Figure S1. SEM RT-qPCR, Leukemia proliferation, and Leukemia Casp3/7-glo 4 Table S1. UPR Gene Array. 5-7 Table S2. DNA Damage Gene Array. 8-10 Table S3. Apoptosis Gene Array. 11-13 Figure S2. Comparison of two borrelidin samples purchased from Sigma. 14 Figure S3. RT-qPCR analysis of OSCC cell lines reveals expression of cell UPR genes in 15 response to borrelidin. Figure S4. RT-qPCR analysis of OSCC cell lines reveals expression of cell death genes in 16 response to borrelidin. Figure S5. ATF4 MEF Proliferation and RT-qPCR. 17 Figure S6. HRESIMS spectrum for borrelidin CR1 2. 18 13 Figure S7. C NMR spectrum of borrelidin CR1 2 recorded at 600 MHz (in CDCl3). 19 1 Figure S8. H NMR spectrum of borrelidin CR1 2 recorded at 600 MHz (in CDCl3). 20 Table S4. NMR spectroscopic data for borrelidin CR1 2 and CR2 3 in CDCl3 and CD3OD 21 at 600 MHz. Figure S9. gCOSY spectrum of borrelidin CR1 2 recorded at 600 MHz (in CDCl3). 22 1 Figure S10. HMBCAD spectrum of borrelidin CR1 2 recorded at 600 MHz (in CDCl3). 23 Figure S11. HSQCAD spectrum of borrelidin CR1 2 recorded at 600 MHz (in CDCl3). 24 Figure S12. Planar structure of borrelidin CR1 2; showing COSY correlation with bold bonds 25 and HMBC correlations with arrow in borrelidin CR1 2. Figure S13. HRESIMS spectrum for borrelidin CR2 3. 26 1 Figure S14. H NMR spectrum of borrelidin CR2 3 recorded at 600 MHz (in CD3OD). 27 Figure S15. gCOSY spectrum of borrelidin CR2 3 recorded at 600 MHz (in CD3OD). 28 Figure S16. HMBCAD spectrum of borrelidin CR2 3 recorded at 600 MHz (in CD3OD). 29 Figure S17. HSQCAD spectrum of borrelidin CR2 3 recorded at 600 MHz (in CD3OD). 30 Experimental Procedures Borrelidin isolation and purification. The parent borrelidin 1 that we identified is commercially available so a detailed structural 20 characterization was not pursued. Borrelidin 1: Isolated as white amorphous solid: [α] D -10.3 (c 0.20, MeOH); IR (film) 3324, -1 2952, 2214, 1699, 1602, 1456, 1377, 1143 cm ; UVmax (λ212 (log ε 3.24), 254 (log ε 2.93), and 280 (log ε 2.51). Borrelidin CR1 2: 20 -1 Isolated as white amorphous solid: [α] D -10.1 (c 0.20, MeOH); IR (film) 3321, 2941, 2215, 1702, 1602, 1456, 1365, 1141 cm ; UVmax (λ) 212 (log ε 3.24), 254 (log ε 2.93), and 280 (log ε 2.51). 2 was determined to have a molecular formula of C28H44N2O5 as suggested by HRESIMS based on [M+Na]+ ion peak at m/z 511.1148 (Figure S6). The 13C and 1H NMR spectra revealed that the molecule was polyketidic in nature; subsequent dereplication revealed it to be a natural product precedent of a known synthetic 13 antibacterial molecule (Figures S7 – 8). The C NMR spectrum recorded in CDCl3 indicated the presence of at least three oxygen- ated methines with chemical shifts at δ 69.5, 73.02 and 76.5 (Table S4). The 13C NMR spectra also indicated two carbonyls (δ 172.5, 178.9) and five signals between δ 118.5- 143.9 indicating the presence of two or three double bonds. These initial NMR analyses accounted for only five of the eight suggested degrees of unsaturation from the molecular formula indicating that the mol- ecule might be macrocyclic. The connectivity from C-1 to C-11 was confirmed by an array of extensive 2D NMR spectra (COSY and HMBC) to construe an 11-carbon aliphatic straight chain starting from a characteristic carbonyl carbon at δC 172.5 (Figures S9- 1 11). Another set of COSY rallying was observed between H-13 to H-17 with the H chemical shifts at C-13 (δH 6.82 (d), δC 143.9), C-14 (δH 6.37 (dd), δC 126.8) and C-15 (δH 6.23 (ddd), δC 138.8) revealing conjugated double bonds with C-13 connected to C-11 via a quaternary carbon at C-12 (δC 118.5). HMBC correlations were observed from H-11 and H-13 to a quaternary carbon C-22 with δC 120.5 suggesting the presence of an isonitrile group. In addition, the pendant attachment of a cyclopentane ring at C-17 was 1 constructed using COSY correlations from H-1’ to H-5’ (Figure S12). The H chemical shift at C-5’ (δH 2.39, δC 49.4) along with an HMBC correlation to δC 178.1 suggested an adjacent carbonyl group completing the connection of the carbonyl to cyclopentane ring. All of these conclusively accounted for the eight degrees of unsaturation initially suggested. Furthermore, the presence of an amine group next to C-6’ fulfilled the requirement of the molecular formula to provide the planar structure of 2. Borrelidin CR2 3: 20 -1 Isolated as white amorphous solid: [α] D -9.8 (c 0.20, MeOH); IR (film) 3300, 2823, 1675, 1423, 1325, 1140 cm ; UVmax (λ) 212 (log ε 3.11), and 280 (log ε 2.28). Cell lines, tumor sections and reagents. Dr. Thomas Carey at the University of Michigan provided sequence validated human OSCC cell lines UMSCC1, UMSCC14A, and UMSCC23. The epidermoid carcinoma cell line A-253 (HTB-41) was from ATCC (Manassas, VA). A549 BAX-/-/-/-, BAK-/- lung adenocarcinoma cells (CLLS1015) were from Sigma-Aldrich (St. Louis, MO). All cell lines were cultured in DMEM with pen-strep and 10% FBS. A549 cells were additionally supplemented with MEM non- essential amino acids Life Technologies (Grand Island, NY) and murine embryonic fibroblast medium was supplemented with es- sential and non-essential amino acids. Commercially obtained borrelidin (B3061) was from Sigma-Aldrich. Immunohistochemistry. Formalin fixed paraffin embedded human head and neck surgical specimens were obtained from Karmanos Cancer Institute (KCI), Detroit, MI with approval from the KCI Protocol Review and Monitoring Committee and the Wayne State University Institutional Review Board. Written informed consent from the donor or the next of kin was obtained for the use of these samples in research. Monoclonal anti-GRP78/BiP (#3177) from Cell Signaling (Beverly, MA) was diluted 1:250 and incubated overnight on tissue sections at 4°C; bound antibodies were detected with the ImmPACT NovaRED peroxidase sub- strate kit from Vector Laboratories (Burlingame, CA). PCR Quantitative real time reverse-transcription PCR (qRT-PCR) and conventional reverse-transcription PCR (RT-PCR) were performed with cDNA prepared with Cells to CT™ from Life Technologies (Carlsbad, CA), as previously described 1. Semi- quantitative RT-PCR analysis of spliced and un-spliced XBP1 was performed with a single human-specific primer pair ACA CGC TTG GGA ATG GAC AC (forward) and CCA TGG GAA GAT GTT CTG GG (reverse); amplicons were electrophoresed on a 2 0.8% agarose gel. 18s ribosomal subunit RNA was used as internal control, fold changes calculated using the delta delta CT method. Quantitative reverse transcription real-time PCR was performed with the following Taqman primer/probe sets from Life Technologies (Grand Island, NY): Human: CHOP/DDIT3 (Hs01090850_m1), 18s (Hs99999901_s1), GADD34 (Hs00169585_m1), ATF3 (Hs00910173_m1), ATF4 (Hs00909569_g1), BiP/GRP78 (Hs99999174_m1), DR5 (Hs00366278_m1), TRB3 (Hs00221754_m1), XBP1s (spliced) (Hs03929085_g1), BIM (Hs00708019_s1), NOXA (Hs00560402_m1), PUMA (Hs00248075_m1), GADD45α (Hs00169255_m1), CEBPβ (Hs00270923_s1), and IRE1α (Hs00176385_m1); Mouse: Noxa (Mm00451763_m1), Puma (Mm00519268_m1), Dr5 (Mm00457866_m1), Trb3 (Mm00454879_m1), and Gadd45β (Mm00435123_m1). Viability and Caspase Assays. Presto Blue Cell Viability Reagent (A21361) from Life Technologies or the luminescent Cell Titer- Glo Cell Viability Assay (G7570) from Promega (Madison, WI) were used according to the manufacturers’ protocols; two-way ANOVA analysis was used to appreciate differences in proliferation. Caspase activation was measured with the luminescent Caspase-Glo 3/7 Assay from Promega. 5000 – 10,000 cells/well were added to 96 well tissue-culture plates the day before treat- ment, as indicated. All experiments were performed at least three times with biologic (triplicate) replicates. DNA Laddering. Genomic DNA was harvested from borrelidin and vehicle treated cells by incubating cell pellets in DNA lysis buffer containing 100 µg/ml proteinase K as previously described 25. Briefly, DNA was extracted two times with Phe- nol:Chloroform:Isoamyl Alcohol and two times with chloroform alone. Precipitated DNA was washed with 70% ethanol, re- suspended in TE supplemented with 0.25 mg/ml RNAse A, and 5µg was electrophoretically resolved on a 1.5% agarose gel. 3 Figure S1. SEM RT-qPCR, Leukemia proliferation, and Leukemia Casp3/7-glo. A. Veh. Tm 0.15625 0.3125 1.25 2.5 5µM 200 150 100 Fold (mRNA) Fold 50 0 CHOP XBP GADD34 ATF4 DR5 NOXA PUMA GADD45A BIM UPR Cell Death B.