Impact of Allosteric Modulation in Drug Discovery: Innovation in Emerging Chemical Modalities

Recent years have seen an unprecedented level of innovation in allosteric drug discovery and development, with multiple drug candidates advancing into clinical studies. From early examples of allosteric drugs like GABA_A receptor modulators (benzodiazepines) in the 1960s to more recent GPCR negative allosteric modulators of CCR5 (maraviroc) approved in 2007, the opportunities for interrogating allosteric sites in drug discovery have expanded to other target classes such as protein-protein interactions, kinases, and nuclear hormone receptors. In this Innovation Letter, the authors highlight the latest advances of allosteric drug discovery from different target classes and novel emerging chemical modalities beyond small molecules.

Assessing cure status prediction from survival data using receiver operating characteristic curves

Survival analysis relies on the hypothesis that, if the follow-up is long enough, the event of interest will eventually be observed for all observations. This assumption, however, is often not realistic. The survival data then contain a cure fraction. A common approach to modelling and analysing this type of data consists in using cure models. Two types of information can therefore be obtained: the survival at a given time and the cure status, both possibly modelled as a function of the covariates. The cure status is often of interest to medical practitioners, and one is usually interested in predicting it based on markers. Receiver operating characteristic, Roc, curves are one way to evaluate the predicted performance; however, the classical Roc curve method is not appropriate since the cure status is partially unobserved due to the presence of censoring in survival data. We propose a Roc curve estimator that aims to evaluate the cured/noncured status classification performance from cure survival data. This estimator, which handles the presence of censoring, decomposes sensitivity and specificity by means of the definition of conditional probability, and estimates these two quantities by means of weighted empirical distribution functions. The mixture cure model is used to calculate the weights. Based on simulations, we demonstrate good performance of the proposed method, and compare it with the classical Roc curve nonparametric estimator that would be obtained if the cure status was fully observed. We also compare our proposed method with the Roc curves of Heagerty et al. (2000) for classical survival analysis. Finally, we illustrate the methodology on a breast cancer dataset.

Measurement of the spin-forbidden dark excitons in MoS2 and MoSe2 monolayers

Excitons with binding energies of a few hundreds of meV control the optical properties of transition metal dichalcogenide monolayers. Knowledge of the fine structure of these excitons is therefore essential to understand the optoelectronic properties of these 2D materials. Here we measure the exciton fine structure of MoS2 and MoSe2 monolayers encapsulated in boron nitride by magneto-photoluminescence spectroscopy in magnetic fields up to 30 T. The experiments performed in transverse magnetic field reveal a brightening of the spin-forbidden dark excitons in MoS2 monolayer: we find that the dark excitons appear at 14 meV below the bright ones. Measurements performed in tilted magnetic field provide a conceivable description of the neutral exciton fine structure. The experimental results are in agreement with a model taking into account the effect of the exchange interaction on both the bright and dark exciton states as well as the interaction with the magnetic field.

Effects of miR-132 on proliferation and apoptosis of pancreatic cancer cells via Hedgehog signaling pathway

OBJECTIVE

Micro ribonucleic acids (miRNAs) and Hedgehog (Hh) signaling pathway play key roles in the proliferation, migration and invasion of tumor cells. The aim of this study was to investigate the role of miR-132 and Hh signaling pathway in the proliferation and apoptosis of pancreatic cancer cells, and to investigate the possible underlying mechanism.

MATERIALS AND METHODS

The expressions of miR-132 and Shh (a ligand of Hh) in clinical pancreatic cancer specimens and pancreatic cancer cell lines were determined by qRT-PCR. Meanwhile, the correlation between the two molecules was analyzed. Pancreatic cancer cell line (MiaPaCe-2a) was transfected with miR-132 mimics and inhibitor. The effects of miR-132 up- and down-regulation on the expressions of miR-132, Shh, Cyclin-D1, cleaved Caspase-3 and cleaved Caspase-9 were detected. In addition, the exact role of miR-132 in the proliferation, apoptosis and distribution of MiaPaCe-2a cells were investigated.

RESULTS

The expression level of miR-132 in pancreatic cancer specimens and pancreatic cancer cell lines was significantly elevated when compared with that of control group. Meanwhile, miR-132 expression was negatively correlated with the expression level of Shh. Moreover, transfection with miR-132 mimics evidently up-regulated miR-132 expression. Moreover, miR-132 up-regulation significantly decreased the mRNA and protein expressions of Shh, facilitated the proliferation of MiaPaCe-2a cells, reduced the protein expressions of Cyclin-D1, cleaved Caspase-3 and cleaved Caspase-9, and suppressed cell apoptosis. On the contrary, miR-132 inhibitor transfection significantly inhibited the proliferative activity of MiaPaCe-2a cells, decreased the proportion of cells in G1 phase, and increased the proportion of cells in G2/M phase.

CONCLUSIONS

MiR-132 promotes proliferation and inhibits apoptosis of pancreatic cancer cells through Hh signaling pathway.

MiR-155-5p affects Wilms' tumor cell proliferation and apoptosis via targeting CREB1

OBJECTIVE

The aim of this study was to explore the role of microRNA-155-5p (miR-155-5p) in regulating the proliferation and apoptosis of Wilm's tumor (WT), and to investigate the possible underlying mechanism.

PATIENTS AND METHODS

The expression levels of miR-155-5p in 37 pairs of WT clinical samples, as well as WT cell line (G401), were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay and flow cytometry assay were used to detect the effects of miR-155-5p on cell proliferation, cycle and apoptosis. Target gene prediction software was applied to screen the potential downstream target gene of miR-155-5p. QRT-PCR, Western blot (WB) and luciferase reporter gene assay proved that cAMP-response element binding protein 1 (CREB1) was the target gene of miR-155-5p. Besides, rescue experiment was conducted to further explore the effect of CREB1 on WT cells.

RESULTS

The expression levels of miR-155-5p in WT tissues and cells were both significantly down-regulated. Importantly, miR-155-5p was found to be involved in the malignant behavior of WT cells. MTT assay and flow cytometry assay demonstrated that miR-155-5p significantly inhibited the proliferation, caused stagnation of cells in G0/G1 phase, and promoted cell apoptosis. CREB1 was verified as a functional target gene of miR-155-5p, which was negatively regulated by miR-155-5p. Rescue experiments indicated that restoring the expression of CREB1 could interfere with the effects of miR-155-5p on WT cells.

CONCLUSIONS

MiR-155-5p could regulate the proliferation, cell cycle and apoptosis of WT cells. These effects were achieved by regulating the expression of CREB1. Furthermore, our study might provide a new theoretical basis for the basic research of WT.

Immune cell infiltration features and related marker genes in lung cancer based on single-cell RNA-seq

PURPOSE

Immune cells in the immune microenvironment of lung cancer have a great impact on the development of lung cancer. Our purpose was to analyze the immune cell infiltration features and related marker genes for lung cancer.

METHODS

Single cell RNA sequencing data of 11,485 lung cancer cells were retrieved from the Gene Expression Omnibus. After quality control and data normalization, cell clustering was performed using the Seurat package. Based on the marker genes of each cell type from the CellMarker database, each cell was divided into G1, G2M, and S phases. Then, differential expression and functional enrichment analyses were performed. CIBERSORT was used to reconstruct immune cell types.

RESULTS

Following cell filtering, highly variable genes were identified for all cells. 14 cell types were clustered. Among them, CD4 + T cell, B cell, plasma cell, natural killer cell and cancer stem cell were the top five cell types. Up-regulated genes were mainly enriched in immune-related biological processes and pathways. Using CIBERSORT, we identified the significantly higher fractions of naïve B cell, memory CD4 + T cell, T follicular helper cell, T regulatory helper cell and M1 macrophage in lung cancer tissues compared to normal tissues. Furthermore, the fractions of resting NK cell, monocyte, M0 macrophage, resting mast cell, eosinophil and neutrophil were significantly lower in tumor tissues than normal tissues.

CONCLUSION

Our findings dissected the immune cell infiltration features and related marker genes for lung cancer, which might provide novel insights for the immunotherapy of lung cancer.

Regioisomeric and enantiomeric analysis of primary triglycerides in human milk by silver ion and chiral HPLC atmospheric pressure chemical ionization-MS

Triglycerides (TG) not only provide energy for infants but have important physiological functions. Understanding the composition and structure of TG in human milk is conducive to the development of infant formulas. In this study, TG species in human milk from 3 provincial capitals (Zhengzhou, Wuhan, and Harbin) in different regions of China were determined through C18 HPLC electrospray ionization tandem mass spectrometry (MS). The results showed that in human milk from these 3 regions, oleoyl-palmitoyl-linoleoylglycerol (OPL; 16.55, 19.20, and 18.67%, respectively) was more abundant than oleoyl-palmitoyl-oleoylglycerol (OPO; 10.08, 10.22, and 12.03%, respectively). Subsequently, regioisomeric and enantiomeric analysis of main TG in the human milk were performed on silver ion and chiral HPLC atmospheric pressure chemical ionization mass spectrometry (APCI)-MS, respectively. The results showed that rac-OPL (above 85%), rac-OPO (above 85%), rac-palmitoyl-oleoyl-oleoylglycerol (PPO; above 90%), and rac-OLaO (above 70%) were the main regioisomers of OPL, OPO, PPO, and lauroyl-oleoyl-oleoylglycerol (LaOO), respectively. The relative ratios of enantiomer pairs of rac-OPL (rac-OPL1 and rac-OPL2) were about 37 and 63%, respectively.

miR-409 down-regulates Jak-Stat pathway to inhibit progression of liver cancer

OBJECTIVE

To elucidate the influence of microRNA-409 and the Jak-Stat pathway on the development of liver cancer.

PATIENTS AND METHODS

The quantitative Real-time polymerase chain reaction (qRT-PCR) method was used to detect the expression of microRNA-409 in hepatocarcinoma, paracancerous tissues and normal liver tissues, and the correlation between its expression and clinicopathological parameters of patients was analyzed, with the area under the microRNA-409 curve (AUC) being detected. The level of microRNA-409 in different liver cancer cells was detected by qPCR. Then it was overexpressed or knock-downed in the liver cancer cells by cell transfection technique. The cell apoptosis and viability after inhibition or overexpression of microRNA-409 were evaluated by propidium iodide (PI) staining and cell counting kit-8 (CCK-8) assay. Subsequently, Jak2 and Stat3 mRNA levels were detected by qPCR in hepatocarcinoma and paracancerous tissues, with their protein levels analyzed by Western blot after microRNA-409 was inhibited or up-regulated. At last, CCK-8 assay was performed to evaluate the effect of Jak2 on cell viability.

RESULTS

Compared with paracancerous and normal liver tissues, the level of microRNA-409 was remarkably reduced in hepatocarcinoma tissues and was negatively correlated with tumor stage, tumor size and overall survival time of patients with liver cancer. Meanwhile, microRNA-409 expression in hepatoma cell lines was also strikingly lower than that in normal liver cells. After overexpression of microRNA-409 in HHCC, cell viability significantly decreased while apoptosis increased, and opposite results were shown in HepG2 cells after miR409 was knock-downed. In liver cancer tissues, the levels of Jak2 and Stat3 were significantly higher than those in adjacent tissues. Additionally, up-regulating microRNA-409 reduced the level of Jak2 and Stat3 protein, while down-regulating it elevated them. In addition, Jak2 could reverse the inhibitory effect of microRNA-409 on the proliferation of hepatoma cells.

CONCLUSIONS

Highly-expressed microRNA-409 can down-regulate the Jak-Stat signaling pathway and inhibit cell proliferation to slow down the progression of liver cancer.

Identification of genetic effects and potential causal polymorphisms of CPM gene impacting milk fatty acid traits in Chinese Holstein

Our previous GWAS revealed 83 significant SNPs and 20 promising candidate genes associated with milk fatty acid traits in dairy cattle. Out of them, the carboxypeptidase M (CPM) gene contains a genome-wide significant SNP, Hapmap49848-BTA-106779, which is strongly associated with myristic acid (C14:0; P = 0.0064). Herein, we aimed to confirm the genetic effects of CPM on milk fatty acids in Chinese Holstein. Seven SNPs were detected by re-sequencing the sequences of entire exons and 3000 bp of up-/downstream flanking regions of the CPM gene, of which three were in 5' flanking region, one in the 3' UTR and three were in the 3' flanking region. Using the Haploview 4.1, we estimated the LD among the identified SNPs and found two haplotype blocks. With the animal model, we performed the SNP- and haplotype-based association analyses, and observed that these SNPs and haplotype blocks mainly had strong genetic associations with medium-chain saturated fatty acids (caproic acid, C6:0; caprylic acid, C8:0; capric acid, C10:0; and lauric acid, C12:0) (P < 0.0001-0.0257). In addition, using the Genomatix software, we predicted that three SNPs in the 5' flanking region of CPM (g.45079507A>G, g.45080228C>A and g.45080335C>G) changed the transcription factor binding sites for PREF (progesterone receptor biding site), ZBRK1 (transcription factor with eight central zinc fingers and an N-terminal KRAB domain), SOX9 (sex-determining region Y-box 9, dimeric binding sites), SOX6 (sex-determining region Y-box 6) and FOXP1-ES (alternative splicing variant of FOXP1, activated in ESCs). Further, the dual-luciferase reporter assay showed these three SNPs altered the transcriptional activity of CPM gene (P ≤ 0.0006). In summary, using the post-GWAS strategy, we first confirmed the significant genetic effects of CPM with milk fatty acids in dairy cattle, and identified three potential causal mutations.

[Change of cervical sagittal alignment after the treatment of growing rods to the early-onset scoliosis]

Objective: To determine the impact of growing rods (GR) technique on cervical alignment in early-onset scoliosis (EOS) through the change of cervical alignment parameters after the GR surgery. Methods: Total of 24 consecutive EOS patients treated in Beijing Chao-Yang Hospital from 2009 to 2018 were retrospectively reviewed (17 males and 7 females). Cervical lordosis, T(1) slope and C(2-7) sagittal vertical axis (C(2-7)SVA), thoracic/lumbar Cobb angle, thoracic kyphosis (TK), global kyphosis Cobb angle, SVA were included in radiographic data in the full spinal standing X-ray before and post operation and at the last follow-up. Based on clinical data, including the upper instrumented vertebra (UIV), proximal junctional kyphosis (PJK) and the number of GR, patients were divided into different groups for statistical analysis. Logistic regression analysis was used to find the independent risk factors of the abnormality of C(2-7)SVA. Results: All patients received at least one time of distraction operation, the mean follow-up was (35±14) months. The C(2-7) Cobb angle increased from 17°±11° to 18°±9° and T(1) slope changed from 28°±13° to 28°±11° and C(2-7)SVA changed from (17±11) mm to (16±10) mm after the operation, but no significant differences were found in those indexes before and after the operation (t=-1.15, 0.14, 0.55, all P>0.05). At the last follow-up after GR technique, the C(2-7) Cobb angle, T(1) slope angle and C(2-7)SVA significantly increased when compared with those before the operation (t=-7.60, -4.08, -2.46, all P<0.05). The △C(2-7) Cobb angle and △T(1) slope angle PJK group was both more significant than those in non-PJK group (t=3.50, 3.25, both P<0.05); while there was no significant difference in the △C(2-7) Cobb angle and △T(1) slope angle when the choice of UIV and the number of GD were taken into account (t=-1.02, -1.61, -0.67, 0.31, all P>0.05). The occurrence of PJK was identified as an independent risk factor for the abnormality of C(2-7)SVA during the GR surgery with logistic regression analysis(OR=11.57, 95%CI: 1.49-91.54, P<0.05). Conclusions: When used for EOS to correct deformity, GR surgery will increase the cervical lordosis and T(1) slope angle of EOS patients. More attention should be paid to the cervical sagittal alignment and cervical sagittal imbalance in EOS patients with PJK.

Comparison of hand-sewn versus modified coupled arterial anastomoses in head and neck reconstruction: a single operator's experience

Microvascular coupler devices have gained wide acceptance as an alternative to the traditional hand-sewn technique in reconstructive surgery. However, no study has directly compared the efficacy of the coupler and hand-sewn techniques in arterial anastomosis during head and neck reconstruction surgery. A total of 123 patients who underwent surgery performed by a single surgeon between 2016 and 2018 were included in this retrospective study. The patients were divided into the coupler group and the hand-sewn group according to the technique of arterial anastomosis used. Patients in the coupler group underwent a special procedure including arterial bifurcation to enlarge the recipient artery diameter. Of the 123 free flap surgeries performed, 56 were done using a coupler and 67 with the standard suture technique. One flap in the coupler group failed due to simultaneous arterial and venous thromboses. One flap in the hand-sewn group was lost due to venous compromise. The overall flap survival rate was 98.4% (n=121). There was a significant decrease in anastomotic time when a coupler was used (P<0.001). The complication and flap loss rates were similar in the coupler and hand-sewn groups. The application of the coupler helped to decrease the anastomotic time and achieved satisfactory vessel patency.

[Comparison of short-term and long-term outcomes between thoracoscopic pneumonectomy and open pneumonectomy for non-small cell lung cancer: a study based on propensity score matching]

Objective: To compare the short-term and long-term results of thoracoscopic and open pneumonectomy for non-small cell lung cancer. Methods: The clinical data of patients with non-small cell lung cancer who underwent pneumonectomy in the Department of Thoracic Surgery, Qingdao University Hospital from January 2008 to December 2016 were collected. Totally 142 patients (55 in the thoracoscopic group and 87 in the open group) were included in the study. A total of 29 pairs of patients were successfully matched by propensity score matching (PSM). Perioperative outcomes and overall survival were compared between the two groups using t test, χ(2) test, Kaplan-Meier curve and Log-rank test, respectively. Results: Camparion with open group, the thoracoscopic group had longer operative time ((209.7±70.2) minutes vs. (171.3±43.5) minutes, t=2.50, P=0.02), more mediastinal lymph node dissection (M(Q(R)): 17(9) vs. 11(10), W=388, P=0.02) and shorter postoperative hospital stay (7.0(3.5) vs. 9.0(3.0), W=285, P=0.03). There was no significant difference in estimated blood loss, postoperative drainage time, dissected lymph node number, dissected lymph node station and perioperative complications. After PSM, there were no signifificant differences found in 3-year survival (71.4% vs. 48.1%, P=0.10) and 3-year disease-free survival (67.4% vs. 47.2%, P=0.13) between the two groups. Conclusion: Thoracoscopic pneumonectomy is safe and feasible for the treatment of non-small cell lung cancer with more mediastinal lymph node dissection and accelerating recovery, and equivalent long-term prognosis when compared with open approach.

Room temperature "optical nanodiamond hyperpolarizer": Physics, design, and operation

Dynamic Nuclear Polarization (DNP) is a powerful suite of techniques that deliver multifold signal enhancements in nuclear magnetic resonance (NMR) and MRI. The generated athermal spin states can also be exploited for quantum sensing and as probes for many-body physics. Typical DNP methods require the use of cryogens, large magnetic fields, and high power microwave excitation, which are expensive and unwieldy. Nanodiamond particles, rich in Nitrogen-Vacancy (NV) centers, have attracted attention as alternative DNP agents because they can potentially be optically hyperpolarized at room temperature. Here, unraveling new physics underlying an optical DNP mechanism first introduced by Ajoy et al. [Sci. Adv. 4, eaar5492 (2018)], we report the realization of a miniature "optical nanodiamond hyperpolarizer," where ¹³C nuclei within the diamond particles are hyperpolarized via the NV centers. The device occupies a compact footprint and operates at room temperature. Instrumental requirements are very modest: low polarizing fields, low optical and microwave irradiation powers, and convenient frequency ranges that enable miniaturization. We obtain the best reported optical ¹³C hyperpolarization in diamond particles exceeding 720 times of the thermal 7 T value (0.86% bulk polarization), corresponding to a ten-million-fold gain in averaging time to detect them by NMR. In addition, the hyperpolarization signal can be background-suppressed by over two-orders of magnitude, retained for multiple-minute long periods at low fields, and deployed efficiently even to ¹³C enriched particles. Besides applications in quantum sensing and bright-contrast MRI imaging, this work opens possibilities for low-cost room-temperature DNP platforms that relay the ¹³C polarization to liquids in contact with the high surface-area particles.

MiR-210 knockdown promotes the development of pancreatic cancer via upregulating E2F3 expression

OBJECTIVE

The aim of this study was to explore the role of microRNA-210 (miR-210) and E2F3 in the development of pancreatic cancer and to investigate the possible underlying mechanism.

PATIENTS AND METHODS

The expression level of miR-210 in pancreatic cancer tissues, para-cancerous tissues, and normal pancreatic tissues was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between miR-210 expression and pathological indicators of pancreatic cancer was analyzed. Meanwhile, the expression of miR-210 in pancreatic cancer cells and normal pancreatic ductal epithelial cells was detected by qRT-PCR. After transfection with miR-210 mimics and inhibitor, the viability and cell cycle of pancreatic cancer cells were detected by cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. The binding condition of miR-210 and E2F3 was verified by Dual-Luciferase reporter gene assay.

RESULTS

MiR-210 was lowly expressed in pancreatic cancer tissues than that of para-cancerous tissues. The expression of miR-210 was negatively correlated with TNM stage and tumor size of pancreatic cancer. In vitro experiments showed that the miR-210 was downregulated in pancreatic cancer cells than that of normal pancreatic ductal epithelial cells. Meanwhile, overexpression of miR-210 arrested cell cycle decreased cell viability and downregulated E2F3 expression in pancreatic cancer cells. Dual-Luciferase reporter gene assay indicated that E2F3 bound to mi-210. Further experiments confirmed that E2F3 was negatively regulated by miR-210.

CONCLUSIONS

MiR-210 knockdown promotes cell proliferation by upregulating E2F3 expression, thereby promoting the progression of pancreatic cancer.

An Ultrastructural Study of the Extruded Polar Tube of Anncaliia algerae (Microsporidia)

All microsporidia share a unique, extracellular spore stage, containing the infective sporoplasm and the apparatus for initiating infection. The polar filament/polar tube when exiting the spore transports the sporoplasm through it into a host cell. While universal, these structures and processes have been enigmatic. This study utilized several types of microscopy, describing and extending our understanding of these structures and their functions. Cryogenically preserved polar tubes vary in diameter from 155 to over 200 nm, noticeably larger than fixed-sectioned or negatively stained samples. The polar tube surface is pleated and covered with fine fibrillar material that projects from the surface and is organized in clusters or tufts. These fibrils may be the sites of glycoproteins providing protection and aiding infectivity. The polar tube surface is ridged with 5-6 nm spacing between ridges, enabling the polar tube to rapidly increase its diameter to facilitate the passage of the various cargo including cylinders, sacs or vesicles filled with particulate material and the intact sporoplasm containing a diplokaryon. The lumen of the tube is lined with a membrane that facilitates this passage. Careful examination of the terminus of the tube indicates that it has a closed tip where the membranes for the terminal sac are located.

Distortion and magnification of four digital cephalometric units

Objectives

To assess the validity of using the calibration ruler for correcting magnification of linear measurements and to explore and compare the vertical and horizontal magnification of four digital cephalometric units.

Methods

An acrylic box was imaged at seven sagittal positions using four digital cephalometric units: Orthopantomograph OC100, Orthopantomograph OC200, Sirona Orthophos CD, and Sirona Orthophos DS. The true linear lengths of the phantom, corrected, and uncorrected linear lengths on the images were measured and compared. The validity of measurements using the calibration ruler was assessed. The magnification values and distortion indices were calculated and compared among the four cephalometric units.

Results

For linear measurements on the mid-sagittal plane and averaged linear measurements on bilateral symmetric sagittal planes, the bias 1.96 STD of the calibration ruler ranged from 1% to 2% for the four cephalometric testing units. For linear measurements on the single lateral sagittal plane, the bias 1.96 STD ranged from 3% to 6%. The vertical scanning charge-coupled device cephalometric unit produced the greatest distortion, ranging from 1.029 to 0.964.

Conclusion

The metal millimeter calibration ruler is an accurate reference for linear measurement magnification correction. Because of unpredictability and machine specificity, the magnification and distortion of a cephalometric unit should be calibrated for the estimation of cephalometric measurement error.

Hyperpolarized relaxometry based nuclear T1 noise spectroscopy in diamond

The origins of spin lifetimes in quantum systems is a matter of importance in several areas of quantum information. Spectrally mapping spin relaxation processes provides insight into their origin and motivates methods to mitigate them. In this paper, we map nuclear relaxation in a prototypical system of [Formula: see text] nuclei in diamond coupled to Nitrogen Vacancy (NV) centers over a wide field range (1 mT-7 T). Nuclear hyperpolarization through optically pumped NV electrons allows signal measurement savings exceeding million-fold over conventional methods. Through a systematic study with varying substitutional electron (P1 center) and [Formula: see text] concentrations, we identify the operational relaxation channels for the nuclei at different fields as well as the dominant role played by [Formula: see text] coupling to the interacting P1 electronic spin bath. These results motivate quantum control techniques for dissipation engineering to boost spin lifetimes in diamond, with applications including engineered quantum memories and hyperpolarized [Formula: see text] imaging.