Discovery of New Selenoureido Analogues of 4-(4-Fluorophenylureido)benzenesulfonamide as Carbonic Anhydrase Inhibitors

A series of benzenesulfonamides bearing selenourea moieties was obtained considering the ureido-sulfonamide SLC-0111, in Phase I clinical trials as antitumor agent, as a lead molecule. All compounds showed interesting inhibition potencies against the physiologically relevant human (h) carbonic anhydrase (hCAs, EC 4.2.1.1) isoforms I, II, IV, and IX. The most flexible analogues in the series 14-19 showed low nanomolar inhibition constants against hCA I, II, and IX. We assessed selected compounds on the in vitro antioxidant properties and binding modes and evaluated ex vivo human prostate (PC3), breast (MDA-MB-231), and colon-rectal (HT-29) cancer cell lines both in normoxic and hypoxic conditions.

β-CA-specific inhibitor dithiocarbamate Fc14-584B: a novel antimycobacterial agent with potential to treat drug-resistant tuberculosis

Inhibition of novel biological pathways in Mycobacterium tuberculosis (Mtb) creates the potential for alternative approaches for treating drug-resistant tuberculosis. In vitro studies have shown that dithiocarbamate-derived β-carbonic anhydrase (β-CA) inhibitors Fc14–594 A and Fc14–584B effectively inhibit the activity of Mtb β-CA enzymes. We screened the dithiocarbamates for toxicity, and studied the in vivo inhibitory effect of the least toxic inhibitor on M. marinum in a zebrafish model. In our toxicity screening, Fc14–584B emerged as the least toxic and showed minimal toxicity in 5-day-old larvae at 300 µM concentration. In vitro inhibition of M. marinum showed that both compounds inhibited growth at a concentration of 75 µM. In vivo inhibition studies using 300 µM Fc14–584B showed significant (p > .05) impairment of bacterial growth in zebrafish larvae at 6 days post infection. Our studies highlight the therapeutic potential of Fc14–584B as a β-CA inhibitor against Mtb, and that dithiocarbamate compounds may be developed into potent anti-tuberculosis drugs.

Advances in new psychoactive substances identification: the U.R.I.To.N. Consortium

Identification of new psychoactive substances (NPS) in biological and non-biological samples represents a hard challenge for forensic toxicologists. Their great chemical variety and the speed with which new NPS are synthesised and spread make stringent the need of advanced tools for their detection based on multidisciplinary approaches. For this reason, in August 2016, the "Unit of Research and Innovation in Forensic Toxicology and Neuroscience of Addiction" (U.R.I.To.N.) was founded by the Forensic Toxicology Division of the University of Florence. In this Research Unit, various professionals (i.e. forensic toxicologists, chemists, physicians) collaborate to study all the aspects of drugs of abuse, especially NPS. Herein, we describe the multidisciplinary approach comprising liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), gas chromatography hyphenated to mass spectrometry (GC-MS) and solution nuclear magnetic resonance analysis that allowed the identification of three NPS such as 1-(benzofuran-5-yl)-N-methylpropan-2-amine, 2-amino-1-(4-bromo-2,5-dimethoxyphenyl)ethan-1-one (bk-2C-B), and 3-(2-aminopropyl)indole (α-methyltryptamine) in seized materials.

Abstract 2931: Targeting membrane-bound carbonic anhydrases in breast cancer to intervene in the metastatic phenotype

Breast cancer is the second leading cause of cancer related deaths among women in the United States. Despite the tremendous progress that has been made towards treating localized tumors, nearly 40,000 women die each year, predominantly from metastatic drug resistance. The tumor microenvironment plays a pivotal role in determining tumor growth, invasion, metastasis, and therapeutic success or failure. Therefore, a therapy targeting the tumor microenvironment is needed to sufficiently preserve the quality of life of cancer patients, by inhibiting metastasis. Elevated levels of Carbonic anhydrase IX (CAIX) expression in primary breast cancers is a marker for highly aggressive and metastatic tumors, especially of the triple negative subtype (TNBC). It is also associated with hypoxia, extracellular acidification, and poor prognosis. Low pH (values of ~6.5-6.8) is toxic to normal cells in the tumor microenvironment while enhancing cancer cell proliferation and tumor growth. Our goal was to compare the structure of a CAIX-mimic bound to ureidosulfonamide inhibitors with the biological activity of these inhibitors in triple negative and estrogen receptor positive (ER+) breast cancer cell lines. CAIX is a reversible enzyme and at low pH (high proton concentration), the enzyme will consume protons, raising pH. Our hypothesis is that CAIX inhibition, in the context of an acidic microenvironment, will dysregulate its ability to maintain the acidic pH preferred by cancer cells which favors their growth and migration. In this study, we have shown the interaction of sulfonamide-based inhibitors with a CAIX-mimic using X-ray crystallography. These structures show that the inhibitors make multiple contacts within the active site cavity. This is consistent with the inhibitor-induced decrease in CAIX activity and to some extent expression. We have also investigated the effect of CA inhibition on breast cancer cell growth, proliferation, activation of cell death pathways and migration. This reveals that, although CA inhibition with the sulfonamide-based compounds inhibits cell growth and migration, it does not activate apoptotic pathways. In total, these observations indicate that CAIX is a viable small molecular drug target for the treatment of metastatic breast cancer.

Citation Format: Mam Y. Mboge, Zhijuan Chen, Brian P. Mahon, Chingkkuang Tu, Alyssa S. Wolff, John V. Mathias, Fabrizio Carta, Claudiu T. Supuran, Rob McKenna, Susan C. Frost. Targeting membrane-bound carbonic anhydrases in breast cancer to intervene in the metastatic phenotype [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2931. doi:10.1158/1538-7445.AM2017-2931

Structure activity study of carbonic anhydrase IX: Selective inhibition with ureido-substituted benzenesulfonamides

Ureido-substituted benzenesulfonamides (USBs) show great promise as selective and potent inhibitors for human carbonic anhydrase hCA IX and XII, with one such compound (SLC-0111/U-F) currently in clinical trials (clinical trials.gov, NCT02215850). In this study, the crystal structures of both hCA II (off-target) and an hCA IX-mimic (target) in complex with selected USBs (U-CH3, U-F, and U-NO2), at resolutions of 1.9 Å or better, are presented, and demonstrate differences in the binding modes within the two isoforms. The presence of residue Phe 131 in hCA II causes steric hindrance (U-CH3, 1765 nM; U-F, 960 nM; U-NO2, 15 nM) whereas in hCA IX (U-CH3, 7 nM; U-F, 45 nM; U-NO2, 1 nM) and hCA XII (U-CH3, 6 nM; U-F, 4 nM; U-NO2, 6 nM), 131 is a Val and Ala, respectively, allows for more favorable binding. Our results provide insight into the mechanism of USB selective inhibition and useful information for structural design and drug development, including synthesis of hybrid USB compounds with improved physiochemical properties.

N-Substituted and ring opened saccharin derivatives selectively inhibit transmembrane, tumor-associated carbonic anhydrases IX and XII

A series of N-substituted saccharins incorporating aryl, alkyl and alkynyl moieties, as well as some ring opened derivatives were prepared and investigated as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1). The widespread cytosolic isoforms CA I and II were not inhibited by these sulfonamides whereas transmembrane, tumor-associated ones were effectively inhibited, with K_Is in the range of 22.1-481nM for CA IX and of 3.9-245nM for hCA XII. Although the inhibition mechanism of these tertiary/secondary sulfonamides is unknown for the moment, the good efficacy and especially selectivity for the inhibition of the tumor-associated over the cytosolic, widespread isoforms, make these derivatives of considerable interest as enzyme inhibitors with various pharmacologic applications.

Synthesis of an acridine orange sulfonamide derivative with potent carbonic anhydrase IX inhibitory action

Acridine orange (AO) a fluorescent cationic dye used for the management of human musculoskeletal sarcomas, due to its strong tumoricidal action and accumulation in the acidic environment typical of hypoxic tumors, was used for the preparation of a primary sulfonamide derivative. The rationale behind the drug design is the fact that hypoxic, acidic tumors overexpress carbonic anhydrase (CA, EC 4.2.1.1) isoforms, such as CA IX, which is involved in pH regulation, proliferation, cell migration and invasion, and this enzyme is strongly inhibited by primary sulfonamides. The AO-sulfonamide derivative was indeed a potent, low nanomolar CA IX inhibitor whereas its inhibition of the cytosolic isoforms CA I and II was in the micromolar range. A second transmembrane, tumor-associated isoform, CA XII, was also effectively inhibited by the AO-sulfonamide derivative, making this compound an interesting theranostic agent for the management of hypoxic tumors.

Carbonic anhydrase activation enhances object recognition memory in mice through phosphorylation of the extracellular signal-regulated kinase in the cortex and the hippocampus

Rats injected with by d-phenylalanine, a carbonic anhydrase (CA) activator, enhanced spatial learning, whereas rats given acetazolamide, a CA inhibitor, exhibited impairments of fear memory consolidation. However, the related mechanisms are unclear. We investigated if CAs are involved in a non-spatial recognition memory task assessed using the object recognition test (ORT). Systemic administration of acetazolamide to male CD1 mice caused amnesia in the ORT and reduced CA activity in brain homogenates, while treatment with d-phenylalanine enhanced memory and increased CA activity. We provided also the first evidence that d-phenylalanine administration rapidly activated extracellular signal-regulated kinase (ERK) pathways, a critical step for memory formation, in the cortex and the hippocampus, two brain areas involved in memory processing. Effects elicited by d-phenylalanine were completely blunted by co-administration of acetazolamide, but not of 1-N-(4-sulfamoylphenyl-ethyl)-2,4,6-trimethylpyridinium perchlorate ^(C18), a CA inhibitor that, differently from acetazolamide, does not cross the blood brain barrier. Our results strongly suggest that brain but not peripheral CAs activation potentiates memory as a result of ERK pathway enhanced activation.

Design and Synthesis of Novel Nonsteroidal Anti-Inflammatory Drugs and Carbonic Anhydrase Inhibitors Hybrids (NSAIDs-CAIs) for the Treatment of Rheumatoid Arthritis

We report the synthesis of a series of hybrid compounds incorporating 6- and 7-substituted coumarins (carbonic anhydrase, CA inhibitors) derivatized with clinically used NSAIDs (indomethacin, sulindac, ketoprofen, ibuprofen, diclofenac, ketorolac, etc., cyclooxygenase inhibitors) as agents for the management of rheumatoid arthritis (RA). Most compounds were effective in inhibiting the RA overexpressed hCA IX and XII, with K_I values in the low nanomolar-subnanomolar ranges. The antihyperalgesic activity of such compounds was assessed by means of the paw-pressure and incapacitance tests using an in vivo RA model. Among all tested compounds, the 7-coumarine hybrid with ibuprofen showed potent and persistent antihyperalgesic effect up to 60 min after administration.

Abstract B51: Regulation of HIF1α under hypoxia by APE1/Ref-1 impacts CA9 expression: Dual-targeting in patient-derived 3D pancreatic cancer models

Half of all patients diagnosed with pancreatic ductal adenocarcinoma (PDAC) die within a year despite extensive surgery and/or a highly aggressive chemotherapy regimen. Several mechanisms are proposed to play a role in PDAC therapeutic resistance, including reactive stroma and hypoxia. Cancer-associated fibroblasts (CAFs) contribute to tumor signaling, fibrosis, inflammation, and hypoxia. Hypoxia signaling creates a more aggressive phenotype with increased potential for metastasis and impairs therapeutic efficacy. Carbonic anhydrase IX (CA9) functions as part of the cellular response to hypoxia to regulate intracellular pH to promote cell survival. Apurinic/Apyrimidinic Endonuclease-1-Reduction/oxidation Effector Factor 1 (APE1/Ref-1) is a multi-functional protein that possesses two major activities: an endonuclease function in DNA base excision repair and a redox signaling function that reduces oxidized transcription factors, enabling them to bind to their DNA target sequences. APE1/Ref-1 regulates several transcription factors involved in survival mechanisms, tumor growth, and hypoxia signaling. We explored the mechanisms underlying PDAC cell responses to hypoxia and modulation of APE1/Ref-1 redox signaling control of hypoxia inducible factor 1 alpha (HIF1α), a critical factor in hypoxia-induced CA9 transcription. We hypothesized that obstructing the HIF-CA9 axis at two points via APE1/Ref-1 inhibition and CA9 inhibition will result in enhanced PDAC cell killing under hypoxic conditions.

Methods: We performed qRT-PCR and Western Blots to confirm changes in CA9 expression in PDAC cells and CAFs following APE1/Ref-1 inhibition and hypoxia exposure. We evaluated the effects of dual-targeting APE1/Ref-1 and CA9 on acidification of tumor cells with an intracellular pH indicator. Proliferation assays were used to assess cell killing following inhibition of APE1/Ref-1 and CA9 under hypoxia. Ex vivo 3-Dimensional co-culture models including both tumor and CAFs were used to examine whether we could enhance the efficacy of APE1/Ref-1 and/or CA9 inhibition with a dual-targeting approach to kill tumor spheroids. To delineate which function of APE1/Ref-1 is critical for observed effects, we used the APE1/Ref-1 redox signaling inhibitor, APX3330, an APE1/Ref-1 repair inhibitor, ARI-3, and an APX3330 analog that does not block APE1/Ref-1 redox activity, RN7-58. To inhibit CA9, we used the sulfonamide derivative, SLC-0111 (Clinical Trial NCT02215850).

Results: HIF1α-mediated induction of CA9 is significantly diminished in PDAC cells following APE1/Ref-1 redox inhibition or knock-down in both patient-derived and established cell lines, as well as pancreatic CAFs. Additionally, dual-targeting of APE1/Ref-1 redox signaling and CA9 results in acidification of PDAC cells and reduces PDAC tumor cell growth under hypoxic conditions as well as in a 3D tumor co-culture model.

The results presented here demonstrate potential clinical utility of blocking APE1/Ref-1 and CA9 function for novel PDAC therapeutic treatment. Ongoing experiments will determine the role of APE1/Ref-1 and CA9 in invasion of tumor cells exposed to hypoxic conditions, as well as the efficacy of dual-targeting APE1/Ref-1 and CA9 in in vivo models of PDAC.

Consequently, our findings further demonstrate a combination approach for blocking important signaling pathways in tumor cells. Our results support our previously published studies using APX3330 and STAT3 inhibition as a dual hit strategy in PDAC cells (Cardoso, Jiang et al. 2012) and APX3330 and Avastin (bevacizumab) for HIF1α-VEGF-signaling inhibition as an anti-angiogenesis combination strategy (Luo, Delaplane et al. 2008, Jiang, Gao et al. 2011, Li, Liu et al. 2014). Continued studies centering on the APE1/Ref-1 redox signaling axis and potential clinical partners for pathway inhibition are ongoing in our laboratories. This approach is supported by the planned phase 1 clinical trial for APX3330 scheduled to begin in mid-2016.

Citation Format: Derek P. Logsdon, Michelle Grimard, Safi Shahda, Nicholas Zyromski, Ernestina Schipani, Fabrizio Carta, Claudiu T. Supuran, Murray Korc, Mircea Ivan, Mark R. Kelley, Melissa L. Fishel.{Authors}. Regulation of HIF1α under hypoxia by APE1/Ref-1 impacts CA9 expression: Dual-targeting in patient-derived 3D pancreatic cancer models. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2016 May 12-15; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2016;76(24 Suppl):Abstract nr B51.

Polyamines and α-Carbonic Anhydrases

Natural products represent a straightforward source for molecular structures bearing a vast array of chemical features and potentially useful for biomedical purposes. Recent examples of this type include the discovery of the coumarins and the polyamine natural products as atypical chemotypes for the inhibition of the metalloenzymes carbonic anhydrases (CAs; EC 4.2.2.1). CA enzymes are established pharmacological targets for important pathologies, which, among others, include glaucoma, hypoxic tumors, and central nervous system (CNS)-affecting diseases. Moreover, they are expressed in many bacteria, fungi and helminths which are the etiological agents of the majority of infectious diseases. In this context, natural products represent the ideal source of new and selective druggable CA modulators for biomedical purposes. Herein we report the state of the art on polyamines of natural origin as well as of synthetic derivatives as inhibitors of human CAs.

Benzenesulfonamides Incorporating Flexible Triazole Moieties Are Highly Effective Carbonic Anhydrase Inhibitors: Synthesis and Kinetic, Crystallographic, Computational, and Intraocular Pressure Lowering Investigations

Herein we report the synthesis of two series of benzenesulfonamide containing compounds that incorporate the phenyl-1,2,3-triazole moieties. We explored the insertion of appropriate linkers, such as ether, thioether, and amino type, into the inner section of the molecules with the intent to confer additional flexibility. All obtained compounds were screened in vitro as inhibitors of the physiologically relevant human (h) isoforms of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1). Many of them were low nanomolar or subnanomolar hCA II, IX, and XII inhibitors, whereas they did not potently inhibit hCA I. Computational and X-ray crystallographic studies of the enzyme-inhibitor adducts helped us to rationalize the obtained results. Some of the sulfonamides reported here showed significant intraocular pressure lowering activity in an animal model of glaucoma.

Phenols and Polyphenols as Carbonic Anhydrase Inhibitors

Phenols are among the largest and most widely distributed groups of secondary metabolites within the plant kingdom. They are implicated in multiple and essential physiological functions. In humans they play an important role as microconstituents of the daily diet, their consumption being considered healthy. The physical and chemical properties of phenolic compounds make these molecules versatile ligands, capable of interacting with a wide range of targets, such as the Carbonic Anhydrases (CAs, EC 4.2.1.1). CAs reversibly catalyze the fundamental reaction of CO₂ hydration to bicarbonate and protons in all living organisms, being actively involved in the regulation of a plethora of patho/physiological processes. This review will discuss the most recent advances in the search of naturally occurring phenols and their synthetic derivatives that inhibit the CAs and their mechanisms of action at molecular level. Plant extracts or mixtures are not considered in the present review.

CO2 and HCO3- Permeability of the Rat Liver Mitochondrial Membrane

Background/Aims: Across the mitochondrial membrane an exceptionally intense exchange of O2 and CO2 occurs. We have asked, 1) whether the CO2 permeability, PM,CO2, of this membrane is also exceptionally high, and 2) whether the mitochondrial membrane is sufficiently permeable to HCO3- to make passage of this ion an alternative pathway for exit of metabolically produced CO2. Methods: The two permeabilities were measured using the previously published mass spectrometric 18O exchange technique to study suspensions of mitochondria freshly isolated from rat livers. The mitochondria were functionally and morphologically in excellent condition. Results: The intramitochondrial CA activity was exclusively localized in the matrix. PM,CO2 of the inner mitochondrial membrane was 0.33 (SD ± 0.03) cm/s, which is the highest value reported for any biological membrane, even two times higher than PM,CO2 of the red cell membrane. PM,HCO3- was 2· 10-6 (SD ± 2· 10-6) cm/s and thus extremely low, almost 3 orders of magnitude lower than PM,HCO3- of the red cell membrane. Conclusion: The inner mitochondrial membrane is almost impermeable to HCO3- but extremely permeable to CO2. Since gas channels are absent, this membrane constitutes a unique example of a membrane of very high gas permeability due to its extremely low content of cholesterol.

Synthesis 4-[2-(2-mercapto-4-oxo-4H-quinazolin-3-yl)-ethyl]-benzenesulfonamides with subnanomolar carbonic anhydrase II and XII inhibitory properties

Condensation of substituted anthranilic acids with 4-isothiocyanatoethyl-benzenesulfonamide led to series of heterocyclic benzenesulfonamides incorporating 2-mercapto-quinazolin-4-one tails. These sulfonamides were investigated as inhibitors of the human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms hCA I and II (cytosolic isozymes), as well as hCA XII (a transmembrane, tumor-associated enzyme also involved in glaucoma-genesis). The new sulfonamides acted as medium potency inhibitors of hCA I (KIs of 28.5-2954nM), being highly effective as hCA II (KIs in the range of 0.62-12.4nM) and XII (KIs of 0.54-7.11nM) inhibitors. All substitution patterns present in these compounds (e.g., halogens, methyl and methoxy moieties, in positions 6, 7 and/or 8 of the 2-mercapto-quinazolin-4-one ring) led to highly effective hCA II/XII inhibitors. These compounds should thus be of interest as preclinical candidates in pathologies in which the activity of these enzymes should be inhibited, such as glaucoma (CA II and XII as targets) or some tumors in which the activity of isoforms CA II and XII is dysregulated.

Regulation of HIF1α under Hypoxia by APE1/Ref-1 Impacts CA9 Expression: Dual Targeting in Patient-Derived 3D Pancreatic Cancer Models

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related mortality in the United States. Aggressive treatment regimens have not changed the disease course, and the median survival has just recently reached a year. Several mechanisms are proposed to play a role in PDAC therapeutic resistance, including hypoxia, which creates a more aggressive phenotype with increased metastatic potential and impaired therapeutic efficacy. AP Endonuclease-1/Redox Effector Factor 1 (APE1/Ref-1) is a multifunctional protein possessing a DNA repair function in base excision repair and the ability to reduce oxidized transcription factors, enabling them to bind to their DNA target sequences. APE1/Ref-1 regulates several transcription factors involved in survival mechanisms, tumor growth, and hypoxia signaling. Here, we explore the mechanisms underlying PDAC cell responses to hypoxia and modulation of APE1/Ref-1 redox signaling activity, which regulates the transcriptional activation of hypoxia-inducible factor 1 alpha (HIF1α). Carbonic anhydrase IX (CA9) is regulated by HIF1α and functions as a part of the cellular response to hypoxia to regulate intracellular pH, thereby promoting cell survival. We hypothesized that modulating APE1/Ref-1 function will block activation of downstream transcription factors, STAT3 and HIF1α, interfering with the hypoxia-induced gene expression. We demonstrate APE1/Ref-1 inhibition in patient-derived and established PDAC cells results in decreased HIF1α-mediated induction of CA9. Furthermore, an ex vivo three-dimensional tumor coculture model demonstrates dramatic enhancement of APE1/Ref-1-induced cell killing upon dual targeting of APE1/Ref-1 and CA9. Both APE1/Ref-1 and CA9 are under clinical development; therefore, these studies have the potential to direct novel PDAC therapeutic treatment. Mol Cancer Ther; 15(11); 2722-32. ©2016 AACR.

Abstract B25: Characterization, targeting, and modulation of carbonic anhydrase IX activity for the development of small-molecule inhibitors to treat triple-negative breast cancer

The microenvironment within a solid tumor is usually heterogeneous with certain regions being acidic and hypoxic. These acidic and hypoxic regions arise from rapidly proliferating cells combined with poor tumor perfusion. Cancer cells cope with these hostile changes in their microenvironment by expressing genes that are essential for survival. One of the coping mechanisms is an upregulation of pH regulatory factors, including carbonic anhydrase IX (CAIX). The action of CAIX helps to maintain physiological pH inside the cell (pHi) while regulating extracellular acidification (pHe). Extracellular acidification of the tumor microenvironment promotes local invasion, metastasis and decreases the effectiveness of adjuvant therapies, thus contributing to poor clinical outcome. Our goal was to compare the structure of a CAIX-mimic bound to ureidosulfonamide inhibitors with the biological activity of these inhibitors in a triple negative breast cancer cell line. CAIX is a reversible enzyme and at low pH (high proton concentration), the enzyme will consume protons, raising pH. Our hypothesis is that CAIX inhibition, in the context of an acidic microenvironment, will dysregulate its ability to maintain the acidic pH preferred by cancer cells which favors their growth and migration. In this study, we have shown the interaction of sulfonamide-based inhibitors using X-ray crystallography methods. These structures show the inhibitors make multiple contacts within the active site cavity. This is consistent with the inhibitor-induced decrease in CAIX activity measured as 18O exchange between H2O16 and H13C18O3 . We have also investigated the effect CAIX inhibition on cancer cell metabolism and extracellular acidification using Seahorse technology. This reveals that CAIX may contribute to the “non-glycolytic” acidification process. In total, these observations indicate that CAIX is a viable small molecular drug target and contribute to our understanding of the function of CAIX in modulating pH in cancer cells.

Citation Format: Mam Y. Mboge, Zhijuan Chen, Brian P. Mahon, Nicole Lamas, Shingkuang Tu, Fabrizio Carta, Claudiu T. Superan, Robert McKenna, Susan C. Frost. Characterization, targeting, and modulation of carbonic anhydrase IX activity for the development of small-molecule inhibitors to treat triple-negative breast cancer. [abstract]. In: Proceedings of the AACR Special Conference: Function of Tumor Microenvironment in Cancer Progression; 2016 Jan 7–10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2016;76(15 Suppl):Abstract nr B25.