Citations

Early detection improves hepatocellular carcinoma (HCC) outcomes, but better noninvasive surveillance tools are needed. We aimed to identify and validate methylated DNA markers (MDMs) for HCC detection. Reduced representation bisulfite sequencing was performed on DNA extracted from 18 HCC and 35 control tissues. Candidate MDMs were confirmed by quantitative methylation‐specific PCR in DNA from independent tissues (74 HCC, 29 controls). A phase I plasma pilot incorporated quantitative allele‐specific real‐time target and signal amplification assays on independent plasma‐extracted DNA from 21 HCC cases and 30 controls with cirrhosis. A phase II plasma study was then performed in 95 HCC cases, 51 controls with cirrhosis, and 98 healthy controls using target enrichment long‐probe quantitative amplified signal (TELQAS) assays. Recursive partitioning identified best MDM combinations. The entire MDM panel was statistically cross‐validated by randomly splitting the data 2:1 for training and testing. Random forest (rForest) regression models performed on the training set predicted disease status in the testing set; median areas under the receiver operating characteristics curve (AUCs; and 95% confidence interval [CI]) were reported after 500 iterations. In phase II, a six‐marker MDM panel (homeobox A1 [HOXA1], empty spiracles homeobox 1 [EMX1], AK055957 , endothelin‐converting enzyme 1 [ECE1], phosphofructokinase [PFKP], and C‐type lectin domain containing 11A [CLEC11A]) normalized by beta‐1,3‐galactosyltransferase 6 (B3GALT6) level yielded a best‐fit AUC of 0.96 (95% CI, 0.93‐0.99) with HCC sensitivity of 95% (88%‐98%) at specificity of 92% (86%‐96%). The panel detected 3 of 4 (75%) stage 0, 39 of 42 (93%) stage A, 13 of 14 (93%) stage B, 28 of 28 (100%) stage C, and 7 of 7 (100%) stage D HCCs. The AUC value for alpha‐fetoprotein (AFP) was 0.80 (0.74‐0.87) compared to 0.94 (0.9‐0.97) for the cross‐validated MDM panel (P < 0.0001). Conclusion : MDMs identified in this study proved to accurately detect HCC by plasma testing. Further optimization and clinical testing of this promising approach are indicated.

Abstract Triple-negative breast cancer (TNBC) is characterized by elevated locoregional recurrence risk despite aggressive local therapies. New tumor-specific radiosensitizers are needed. We hypothesized that the ATR inhibitor, VX-970 (now known as M6620), would preferentially radiosensitize TNBC. Noncancerous breast epithelial and TNBC cell lines were investigated in clonogenic survival, cell cycle, and DNA damage signaling and repair assays. In addition, patient-derived xenograft (PDX) models generated prospectively as part of a neoadjuvant chemotherapy study from either baseline tumor biopsies or surgical specimens with chemoresistant residual disease were assessed for sensitivity to fractionated radiotherapy, VX-970, or the combination. To explore potential response biomarkers, exome sequencing was assessed for germline and/or somatic alterations in homologous recombination (HR) genes and other alterations associated with ATR inhibitor sensitivity. VX-970 preferentially inhibited ATR-Chk1-CDC25a signaling, abrogated the radiotherapy-induced G2–M checkpoint, delayed resolution of DNA double-strand breaks, and reduced colony formation after radiotherapy in TNBC cells relative to normal-like breast epithelial cells. In vivo, VX-970 did not exhibit significant single-agent activity at the dose administered even in the context of genomic alterations predictive of ATR inhibitor responsiveness, but significantly sensitized TNBC PDXs to radiotherapy. Exome sequencing and functional testing demonstrated that combination therapy was effective in both HR-proficient and -deficient models. PDXs established from patients with chemoresistant TNBC were also highly radiosensitized. In conclusion, VX-970 is a tumor-specific radiosensitizer for TNBC. Patients with residual TNBC after neoadjuvant chemotherapy, a subset at particularly high risk of relapse, may be ideally suited for this treatment intensification strategy. Mol Cancer Ther; 17(11); 2462–72. ©2018 AACR.

BACKGROUND: In patients who receive a nondepolarizing neuromuscular blocking drug (NMBD) during anesthesia, undetected postoperative residual neuromuscular block is a common occurrence that carries a risk of potentially serious adverse events, particularly postoperative pulmonary complications. There is abundant evidence that residual block can be prevented when real-time (quantitative) neuromuscular monitoring with measurement of the train-of-four ratio is used to guide NMBD administration and reversal. Nevertheless, a significant percentage of anesthesiologists fail to use quantitative devices or even conventional peripheral nerve stimulators routinely. Our hypothesis was that a contributing factor to the nonutilization of neuromuscular monitoring was anesthesiologists’ overconfidence in their knowledge and ability to manage the use of NMBDs without such guidance. METHODS: We conducted an Internet-based multilingual survey among anesthesiologists worldwide. We asked respondents to answer 9 true/false questions related to the use of neuromuscular blocking drugs. Participants were also asked to rate their confidence in the accuracy of each of their answers on a scale of 50% (pure guess) to 100% (certain of answer). RESULTS: Two thousand five hundred sixty persons accessed the website; of these, 1629 anesthesiologists from 80 countries completed the 9-question survey. The respondents correctly answered only 57% of the questions. In contrast, the mean confidence exhibited by the respondents was 84%, which was significantly greater than their accuracy. Of the 1629 respondents, 1496 (92%) were overconfident. CONCLUSIONS: The anesthesiologists surveyed expressed overconfidence in their knowledge and ability to manage the use of NMBDs. This overconfidence may be partially responsible for the failure to adopt routine perioperative neuromuscular monitoring. When clinicians are highly confident in their knowledge about a procedure, they are less likely to modify their clinical practice or seek further guidance on its use.

Abstract Purpose: TNBC represents an aggressive subtype characterized by earlier relapse and worse survival compared to non-TNBC. Patients with residual TNBC after neoadjuvant chemotherapy (NAC) have a high risk of locoregional recurrence despite aggressive subsequent local therapies, including RT. Thus, new radiosensitizers that address chemoresistant TNBC (i.e residual disease after NAC) are needed. ATR plays a key role in the cellular response to replication stress and DNA damage. TNBC is characterized by G1 checkpoint loss, homologous recombination deficiency (HRD), and other features which increase dependence on ATR pathway signaling. We hypothesized that VX-970, a selective inhibitor of ATR, would effectively radiosensitize TNBC. Methods: Cell lines representing varying subtypes of TNBC (MDA-MB-231, HCC1806, and BT-549) and the normal breast epithelial cell line MCF10a were investigated in clonogenic survival, cell cycle, and DNA damage signaling and repair assays. In addition, Mayo Clinic (MC)TNBC1 and MCTNBC2, patient derived xenograft models (PDXs) generated prospectively from baseline and chemoresistant residual disease surgical specimens after NAC, respectively, of unique patients in the Breast Cancer Genome Guided Therapy Study were analyzed. Tumors were injected into hind-legs of athymic nude mice and animals were randomized to: 1) Vehicle 2) RT 3) VX-970 4) RT + VX-970. RT was delivered in 5 daily fractions of 2 Gy. VX-970 was administered daily 1 hour prior to RT at a dose of 60 mg/kg. Exome sequencing was assessed for germ-line and/or somatic alterations in HR genes and an ex-vivo RAD51 foci formation assay was applied to confirm the functional status of HR in each PDX model. Results: In vitro, VX-970 preferentially inhibited ATR-Chk1-CDC25a signaling, abrogated the RT-induced G2/M checkpoint, delayed resolution of γH2AX and 53BP1 foci and reduced colony formation after RT in MDA-MB-231, HCC1806, and BT-549 relative to MCF10a. In vivo, VX-970 did not exhibit single agent activity at the dose administered but markedly sensitized both MCTNBC1 and MCTNBC2 to RT, suggesting that VX-970 could overcome chemoresistant TNBC biology. For MCTNBC1 and MCTNBC2, the median time to tumor tripling was 26 vs 49 days (p=0.002) and 25 vs 43 days (p=0.006) for the RT and RT + VX-970 groups, respectively. Ex-vivo RAD51 foci formation was robust in MCTNBC1, a PDX without HR gene alterations. In contrast, there was no RT-induced RAD51 foci formation in MCTNBC2, suggesting a BRCA1 mutation in the corresponding human tumor resulted in loss of HR function in that model. Conclusion: VX-970 + RT effectively radiosensitized TNBC PDXs established from both pre-treatment biopsy specimens and chemoresistant residual tumor samples and in both HR deficient and HR proficient settings. ATR inhibition should be investigated in the clinic in combination with RT for patients with residual TNBC after NAC. Citation Format: Robert W. Mutter, Mohamed M. Kahila, Xinyi Tu, Qin Zhou, Jia Yu, Krishna R. Kalari, Liewei Wang, Judy C. Boughey, Matthew P. Goetz, Jann N. Sarkaria, Zhenkun Lou. ATR inhibition is a promising radiosensitizing strategy for chemotherapy-resistant triple negative breast cancer (TNBC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 840.