Acoustic-holography-patterned primary hepatocytes possess liver functions.

Acoustic holography (AH), a promising approach for cell patterning, emerges as a powerful tool for constructing novel invitro 3D models that mimic organs and cancers features. However, understanding changes in cell function post-AH remains limited. Furthermore, replicating complex physiological and pathological processes solely with cell lines proves challenging. Here, we employed acoustical holographic lattice to assemble primary hepatocytes directly isolated from mice into a cell cluster matrix to construct a liver-shaped tissue sample. For the first time, we evaluated the liver functions of AH-patterned primary hepatocytes. The patterned model exhibited large numbers of self-assembled spheroids and superior multifarious core hepatocyte functions compared to cells in 2D and traditional 3D culture models. AH offers a robust protocol for long-term in vitro culture of primary cells, underscoring its potential for future applications in disease pathogenesis research, drug testing, and organ replacement therapy.

Revitalizing liver function in mice with liver failure through transplantation of 3D-bioprinted liver with expanded primary hepatocytes.

The utilization of three-dimensional (3D) bioprinting technology to create a transplantable bioartificial liver emerges as a promising remedy for the scarcity of liver donors. This study outlines our strategy for constructing a 3D-bioprinted liver, using in vitro-expanded primary hepatocytes recognized for their safety and enhanced functional robustness as hepatic cell sources for bioartificial liver construction. In addition, we have developed bioink biomaterials with mechanical and rheological properties, as well as printing capabilities, tailored for 3D bioprinting. Upon heterotopic transplantation into the mesentery of tyrosinemia or 90% hepatectomy mice, our 3D-bioprinted liver effectively restored lost liver functions, consequently extending the life span of mice afflicted with liver injuries. Notably, the inclusion of an artificial blood vessel in our 3D-bioprinted liver allowed for biomolecule exchange with host blood vessels, demonstrating, in principle, the rapid integration of the bioartificial liver into the host vascular system. This model underscores the therapeutic potential of transplantation for the treatment of liver failure diseases.

Value of quantitative microsurface structure analysis for evaluating the invasion depth of type 0-II early gastric cancer.

Background and Aim: The microsurface structure reflects the degree of damage to the glands, which is related to the invasion depth of early gastric cancer. To evaluate the diagnostic value of quantitative microsurface structure analysis for estimating the invasion depth of early gastric cancer. Methods: White-light imaging and narrow-band imaging (NBI) endoscopy were used to visualize the lesions of the included patients. The area ratio and depth-predicting score (DPS) of each patient were calculated; meanwhile, each lesion was examined by endoscopic ultrasonography (EUS). Results: Ninety-three patients were included between 2016 and 2019. Microsurface structure is related to the histological differentiation and progression of early gastric cancer. The receiver operating characteristic curve showed that when an area ratio of 80.3% was used as a cut-off value for distinguishing mucosal (M) and submucosal (SM) type 0-II gastric cancers, the sensitivity, specificity, and accuracy were 82.9%, 80.2%, and 91.6%, respectively. The accuracies for distinguishing M/SM differentiated and undifferentiated early gastric cancers were 87.4% and 84.8%, respectively. The accuracy of EUS for distinguishing M/SM early gastric cancer was 74.9%. DPS can only distinguish M-SM1 (SM infiltration <500 µm)/SM (SM infiltration ≥500 µm) with an accuracy of 83.8%. The accuracy of using area ratio for distinguishing 0-II early gastric cancers was better than those of using DPS and EUS (P < 0.05). Conclusion: Quantitative analysis of microsurface structure can be performed to assess M/SM type 0-II gastric cancer and is expected to be effective for judging the invasion depth of gastric cancer.

Rapid Self-Assembly Mini-Livers Protect Mice Against Severe Hepatectomy-Induced Liver Failure.

The construction of bioartificial livers, such as liver organoids, offers significant promise for disease modeling, drug development, and regenerative medicine. However, existing methods for generating liver organoids have limitations, including lengthy and complex processes (taking 6-8 weeks or longer), safety concerns associated with pluripotency, limited functionality of pluripotent stem cell-derived hepatocytes, and small, highly variable sizes (typically ≈50-500 µm in diameter). Prolonged culture also leads to the formation of necrotic cores, further restricting size and function. In this study, a straightforward and time-efficient approach is developed for creating rapid self-assembly mini-livers (RSALs) within 12 h. Additionally, primary hepatocytes are significantly expanded in vitro for use as seeding cells. RSALs exhibit consistent larger sizes (5.5 mm in diameter), improved cell viability (99%), and enhanced liver functionality. Notably, RSALs are functionally vascularized within 2 weeks post-transplantation into the mesentery of mice. These authentic hepatocyte-based RSALs effectively protect mice from 90%-hepatectomy-induced liver failure, demonstrating the potential of bioartificial liver-based therapy.

Prediction of Clinical Precision Chemotherapy by Patient-Derived 3D Bioprinting Models of Colorectal Cancer and Its Liver Metastases.

Methods accurately predicting the responses of colorectal cancer (CRC) and colorectal cancer liver metastasis (CRLM) to personalized chemotherapy remain limited due to tumor heterogeneity. This study introduces an innovative patient-derived CRC and CRLM tumor model for preclinical investigation, utilizing 3d-bioprinting (3DP) technology. Efficient construction of homogeneous in vitro 3D models of CRC/CRLM is achieved through the application of patient-derived primary tumor cells and 3D bioprinting with bioink. Genomic and histological analyses affirm that the CRC/CRLM 3DP tumor models effectively retain parental tumor biomarkers and mutation profiles. In vitro tests evaluating chemotherapeutic drug sensitivities reveal substantial tumor heterogeneity in chemotherapy responses within the 3DP CRC/CRLM models. Furthermore, a robust correlation is evident between the drug response in the CRLM 3DP model and the clinical outcomes of neoadjuvant chemotherapy. These findings imply a significant potential for the application of patient-derived 3DP cancer models in precision chemotherapy prediction and preclinical research for CRC/CRLM.

Gas Sensor Array Fault Diagnosis Based on Multi-Dimensional Fusion, an Attention Mechanism, and Multi-Task Learning.

With the development of gas sensor arrays and computational technology, machine olfactory systems have been widely used in environmental monitoring, medical diagnosis, and other fields. The reliable and stable operation of gas sensing systems depends heavily on the accuracy of the sensors outputs. Therefore, the realization of accurate gas sensor array fault diagnosis is essential to monitor the working status of sensor arrays and ensure the normal operation of the whole system. The existing methods extract features from a single dimension and require the separate training of models for multiple diagnosis tasks, which limits diagnostic accuracy and efficiency. To address these limitations, for this study, a novel fault diagnosis network based on multi-dimensional feature fusion, an attention mechanism, and multi-task learning, MAM-Net, was developed and applied to gas sensor arrays. First, feature fusion models were applied to extract deep and comprehensive features from the original data in multiple dimensions. A residual network equipped with convolutional block attention modules and a Bi-LSTM network were designed for two-dimensional and one-dimensional signals to capture spatial and temporal features simultaneously. Subsequently, a concatenation layer was constructed using feature stitching to integrate the fault details of different dimensions and avoid ignoring useful information. Finally, a multi-task learning module was designed for the parallel learning of the sensor fault diagnosis to effectively improve the diagnosis capability. The experimental results derived from using the proposed framework on gas sensor datasets across different amounts of data, balanced and unbalanced datasets, and different experimental settings show that the proposed framework outperforms the other available methods and demonstrates good recognition accuracy and robustness.

Tumor microenvironment-responsive spherical nucleic acid nanoparticles for enhanced chemo-immunotherapy.

Certain chemotherapeutics can induce tumor cells' immunogenic cell death (ICD), release tumor antigens, and thereby trigger personalized antitumor immune responses. Co-delivery of adjuvants using nanocarriers could amplify the ICD-induced tumor-specific immunity achieving a synergistic chemo-immunotherapeutic effect. However, complicated preparation, low drug loading efficiency, and potential carrier-associated toxicity are the major challenges that limited its clinical applications. Herein, a carrier-free core-shell nanoparticle (MPLA-CpG-sMMP9-DOX, MCMD NPs) was constructed by facile self-assembly of spherical nucleic acids (SNA) with two adjuvants of CpG ODN and monophosphoryl lipid A (MPLA) as a core and doxorubicin (DOX) radially around the dual-adjuvants SNA as a shell. The results demonstrated that MCMD NPs could enhance drugs accumulation in tumors, and release DOX upon enzymatic degradation of matrix metalloproteinase-9 (MMP-9) peptide in the tumor microenvironment (TME), which enhanced the direct-killing effect of DOX on tumor cells. The core of MPLA-CpG SNA efficiently boosted the ICD-induced antitumor immune response to further attack tumor cells. Thus, MCMD NPs achieved a synergistic therapeutic effect of chemo-immunotherapy with reduced off-target toxicity. This study provided an efficient strategy for the development of a carrier-free nano-delivery system for enhanced cancer chemo-immunotherapy.

PIM1 promotes hepatic conversion by suppressing reprogramming-induced ferroptosis and cell cycle arrest.

Protein kinase-mediated phosphorylation plays a critical role in many biological processes. However, the identification of key regulatory kinases is still a great challenge. Here, we develop a trans-omics-based method, central kinase inference, to predict potentially key kinases by integrating quantitative transcriptomic and phosphoproteomic data. Using known kinases associated with anti-cancer drug resistance, the accuracy of our method denoted by the area under the curve is 5.2% to 29.5% higher than Kinase-Substrate Enrichment Analysis. We further use this method to analyze trans-omic data in hepatocyte maturation and hepatic reprogramming of human dermal fibroblasts, uncovering 5 kinases as regulators in the two processes. Further experiments reveal that a serine/threonine kinase, PIM1, promotes hepatic conversion and protects human dermal fibroblasts from reprogramming-induced ferroptosis and cell cycle arrest. This study not only reveals new regulatory kinases, but also provides a helpful method that might be extended to predict central kinases involved in other biological processes.

Inhibition of TWEAK/Tnfrsf12a axis protects against acute liver failure by suppressing RIPK1-dependent apoptosis.

Acute liver failure (ALF) is a severe clinical syndrome characterized by massive death of hepatocytes in a short time, resulting in coagulopathy and hepatic encephalopathy, with a high mortality in patients without pre-existing liver disease. Effective treatment of ALF is currently limited to liver transplantation, highlighting the need for new target therapies. Here, we found that expression of hepatic tumor necrosis factor-like weak inducer of apoptosis (TWEAK) and its receptor tumor necrosis factor receptor superfamily member 12A (Tnfrsf12a) were significantly increased during ALF induced by thioacetamide (TAA) or acetaminophen (APAP). Inhibition of TWEAK/Tnfrsf12a axis markedly attenuated TAA or APAP-induced ALF. Moreover, our results demonstrated that TWEAK/Tnfrsf12a axis induced receptor-interacting protein kinase 1 (RIPK1)-dependent apoptosis of hepatocytes, instead of necroptosis or pyroptosis. Notably, hepatic TNFRSF12A and TWEAK levels were also significantly increased in liver biopsies from ALF patients. In summary, our results demonstrate that during ALF, TWEAK/Tnfrsf12a axis activates RIPK1 in hepatocytes, leading to RIPK1-dependent apoptosis and subsequent liver injury. Therefore, inhibition of either TWEAK/Tnfrsf12a axis or RIPK1-dependent apoptosis attenuates liver injury, providing a new potential therapeutic target for the treatment of ALF.

Snare-assisted flexible endoscope in trans-gastric endoscopic gallbladder-preserving surgery: A pilot animal study.

BACKGROUND: Natural orifice transluminal endoscopic surgery (NOTES) gallbladder-preserving surgery by flexible endoscopy is an emerging technology. However, the gallbladder fails to obtain traction and positioning functions during the operation. AIM: To evaluate the feasibility and safety of a new surgical method, "snare-assisted pure NOTES gallbladder-preserving surgery". METHODS: Eight miniature pigs were randomly divided into the experimental group [NOTES gallbladder-preserving surgery using the snare device, snare assisted (SA)] and the control group (NOTES gallbladder-preserving surgery without using the snare device, NC), with four cases in each group. The differences between the two groups of animals in operating time, operating workload, complications, adverse events, white blood cells, and liver function were determined. RESULTS: No differences were found in the surgical success rate, gallbladder incision closure, white blood cell count, or liver function between the two groups. The total operating time, gallbladder incision blood loss, gallbladder disorientation time, gallbladder incision closure time, and workload scores on the National Aeronautics and Space Administration-Task Load Index were significantly reduced in the SA group (P < 0.05). CONCLUSION: These results indicated that snare-assisted pure NOTES gallbladder-preservation surgery using standard endoscopic instruments reduced the difficulty of operation, shortened operation time, and did not increase complications in pigs. A new method for pure NOTES gallbladder-preservation surgery was provided.

Doxorubicin and CpG loaded liposomal spherical nucleic acid for enhanced Cancer treatment.

Chemotherapeutics that can trigger immunogenic cell death (ICD) and release tumor-specific antigens are effective on treating a variety of cancers. The codelivery of chemotherapeutics with adjuvants is a promising strategy to achieve synergistic therapeutic effect. However, low drug loading and complicated preparation of current delivery systems lead to carrier-associated toxicity and immunogenicity. Herein, we developed a facile approach to construct liposomal spherical nucleic acids (SNA) by the self-assembly of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE)-doxorubicin conjugate and DOPE-matrix metalloproteinases-9 (MMP-9) responsive peptide-CpG conjugate (DOPE-MMP-CpG). Liposomal SNAs efficiently co-delivered DOX and CpG into tumors and released the two drugs upon biological stimuli of MMP-9 enzyme in tumor microenvironment (TME) and high concentration of endogenous glutathione in tumor cells. We demonstrated that liposomal SNA enhanced activation of dendritic cells (DCs), promoted expansion of CD8+ and CD4+ T cells in both tumors and spleen, inhibited tumor growth, and extended animal survival. This work provided a simple strategy of delivering chemotherapeutics and adjuvants to tumors with synergistic therapeutic effect and reduced side effect.

Three-dimensional bio-printing of primary human hepatocellular carcinoma for personalized medicine.

Hepatocellular carcinoma (HCC) is one of the most lethal tumors worldwide. This study aims to address the lack of faithful and available in vitro models for patient-specific drug screening for HCC. We recently established a novel modeling system using three-dimensional (3D) bioprinting technology and constructed hepatorganoids with HepaRG cells, which retain the liver function and prolong the survival of mice with liver failure after abdominal transplantation. Here we extend this modeling system to establish individualized model for hepatocellular carcinoma. HCC specimens were obtained from six patients after surgery. Primary HCC cells were isolated and mixed with gelatin and sodium alginate to form the bioink for printing. Patient-derived three-dimensional bio-printed HCC (3DP-HCC) models were successfully established afterward and grew well during long-term culture. These models retained the features of parental HCCs, including stable expression of the biomarker, stable maintenances of the genetic alterations and expression profiles. 3DP-HCC models are capable of displaying the results of drug screening intuitively and quantitatively. In conclusion, 3DP-HCC models are faithful in vitro models that are reliable in long-term culture and able to predict patient-specific drugs for personalized treatment.

Application of a 3D Bioprinted Hepatocellular Carcinoma Cell Model in Antitumor Drug Research.

The existing in vitro models for antitumor drug screening have great limitations. Many compounds that inhibit 2D cultured cells do not exhibit the same pharmacological effects in vivo, thereby wasting human and material resources as well as time during drug development. Therefore, developing new models is critical. The 3D bioprinting technology has greater advantages in constructing human tissue compared with sandwich culture and organoid construction. Here, we used 3D bioprinting technology to construct a 3D model with HepG2 cells (3DP-HepG2). The biological activities of the model were evaluated by immunofluorescence, real-time quantitative PCR, and transcriptome sequencing. Compared with the traditional 2D cultured tumor cells (2D-HepG2), 3DP-HepG2 showed significantly improved expression of tumor-related genes, including ALB, AFP, CD133, IL-8, EpCAM, CD24, and ß-TGF genes. Transcriptome sequencing analysis revealed large differences in gene expression between 3DP-HepG2 and 2D-HepG2, especially genes related to hepatocyte function and tumor. We also compared the effects of antitumor drugs in 3DP-HepG2 and 2D-HepG2, and found that the large differences in drug resistance genes between the models may cause differences in the drugs' pharmacodynamics.

Conversion of Fibroblasts to Hepatocytes In Vitro.

Primary hepatocytes are widely used in regenerative medicine, drug metabolism analysis, and in vitro drug screens. To overcome the shortage of liver donors, several strategies, such as differentiation of pluripotent stem cells and transdifferentiation from somatic cells, were developed to generate hepatocytes from alternative sources. Here, we describe in detail lenti-virus-based procedure for direct conversion of human fibroblasts to hepatocytes (hiHep cells) in vitro. A detailed protocol for preparation of human fibroblasts from scar tissues is also provided. Based on this protocol, FOXA3, HNF1A, and HNF4A are introduced into SV40-large-T-antigen-expressing human scar fibroblasts by lenti-virus. It usually takes about 5-7 days to get epithelial hiHep colonies. SV40-large-T-antigen-expressing hiHep (hiHepLT) cells are proliferative and can be expanded to a large number for potential uses.

The preS deletion of hepatitis B virus (HBV) is associated with liver fibrosis progression in patients with chronic HBV infection.

BACKGROUND AND AIMS: Limited data are available regarding the association of hepatitis B virus (HBV) mutations with liver fibrosis in HBV infection. The study aimed to clarify whether HBV preS deletion mutation is associated with liver fibrosis progression. METHODS: A total of 469 patients were enrolled, including 324 with chronic hepatitis B (CHB), 28 with HBV-related compensated liver cirrhosis (LC), and 117 with HBV-related decompensated LC. All CHB and compensated LC patients received liver biopsy. Fibrosis grade was assessed using METAVIR score. HBV preS deletion was determined by direct sequencing and verified by clonal sequencing. RESULTS: Overall preS deletion was detected in 12.6% (59/469) patients, specifically, in 7.51% (13/173), 10.60% (16/151), and 20.69% (30/145) of patients with no-to-mild liver fibrosis (F0-1), moderate-to-severe liver fibrosis (F2-3), and cirrhosis (F4), respectively (p < 0.01). Patients with preS-deleted HBV had lower serum HBV DNA and albumin levels compared to patients with wild-type HBV. The median length of preS deletion was 39-base pairs (bp) (3-204 bp) and the deletion most frequently emerged in preS2 initial region. Multivariate analysis identified the preS2 deletion rather than preS1 deletion to be an independent risk factor of significant fibrosis, i.e., METAVIR F ≥ 2 (p = 0.007). In addition, preS-deleted viral sequences were detected in the pool of intrahepatic HBV covalently closed circular DNA. CONCLUSIONS: HBV preS deletion is positively associated with liver fibrosis progression in chronic HBV-infected patients. HBV preS2 deletion may serve as a warning indicator for liver fibrosis progression.

2-Thiophene ethylamine modified hyaluronic acid with its application on hepatocytes culture.

Hyaluronic acid (HA) is a component of extracellular matrix, which is important for cell functions and tissue integrity. Biosynthesized HA, as well as its derivatives, is widely used in cosmetics industry, biochemical medicine and medical surgery. In this research, we report a new hyaluronic acid derivative synthesized by amidation of hyaluronic acid with 2-thiophene ethylamine (2TEA). 2-chloro-dimethoxy-1,3,5-triazine (CDMT) served as the activating agent of the carboxylic groups. Primary mouse hepatocytes cultured with this derivative HA-2TEA maintained their epithelial morphology and showed better hepatic functions. This result was confirmed by the higher expression levels of hepatic functional genes in primary hepatocyte cultured with HA-2TEA derivative. Moreover, the protein levels of several hepatic genes were further confirmed by immunofluorescence staining. Thus HA-2TEA(2-thiopheneethylamine) derivative demonstrated good capacity on hepatocytes culture, and maintained hepatocyte functions in vitro.

Pericentral hepatocytes produce insulin-like growth factor-2 to promote liver regeneration during selected injuries in mice.

Liver regeneration (LR) happens after various types of injuries. Unlike the well-studied LR caused by partial hepatectomy (PHx), there is accumulating evidence suggesting that LR during other injuries may result from unknown mechanisms. In this study, we found that insulin-like growth factor 2 (IGF-2) was drastically induced following the liver injuries caused by tyrosinemia or long-term treatments of CCl4 . However, this was not observed during the early phase of acute liver injuries after PHx or single treatment of CCl4 . Remarkably, most IGF-2-expressing hepatocytes were located at the histological area around the central vein of the liver lobule after the liver injuries caused either in fumarylacetoacetate hydrolase-deficient mice or in CCl4 chronically treated mice. Hepatocyte proliferation in vivo was significantly promoted by induced IGF-2 overexpression, which could be inhibited by adeno-associated virus-delivered IGF-2 short hairpin RNAs or linsitinib, an inhibitor of IGF-2 signaling. Proliferating hepatocytes in vivo responded to IGF-2 through both insulin receptor and IGF-1 receptor. IGF-2 also significantly promoted DNA synthesis of primary hepatocytes in vitro. More interestingly, the significantly induced IGF-2 was also found to colocalize with glutamine synthetase in the region enriched with proliferating hepatocytes for the liver samples from patients with liver fibrosis. CONCLUSION: IGF-2 is produced by pericentral hepatocytes to promote hepatocyte proliferation and repair tissue damage in the setting of chronic liver injury, which is distinct from the signaling that occurs post-PHx. (Hepatology 2017;66:2002-2015).

Homology-mediated end joining-based targeted integration using CRISPR/Cas9.

Targeted integration of transgenes can be achieved by strategies based on homologous recombination (HR), microhomology-mediated end joining (MMEJ) or non-homologous end joining (NHEJ). The more generally used HR is inefficient for achieving gene integration in animal embryos and tissues, because it occurs only during cell division, although MMEJ and NHEJ can elevate the efficiency in some systems. Here we devise a homology-mediated end joining (HMEJ)-based strategy, using CRISPR/Cas9-mediated cleavage of both transgene donor vector that contains guide RNA target sites and ∼800 bp of homology arms, and the targeted genome. We found no significant improvement of the targeting efficiency by the HMEJ-based method in either mouse embryonic stem cells or the neuroblastoma cell line, N2a, compared to the HR-based method. However, the HMEJ-based method yielded a higher knock-in efficiency in HEK293T cells, primary astrocytes and neurons. More importantly, this approach achieved transgene integration in mouse and monkey embryos, as well as in hepatocytes and neurons in vivo, with an efficiency much greater than HR-, NHEJ- and MMEJ-based strategies. Thus, the HMEJ-based strategy may be useful for a variety of applications, including gene editing to generate animal models and for targeted gene therapies.

Selective Inhibitors of Histone Deacetylases 1 and 2 Synergize with Azacitidine in Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is a heterogeneous group of hematopoietic stem cell disorders characterized by defects in myeloid differentiation and increased proliferation of neoplastic hematopoietic precursor cells. Outcomes for patients with AML remain poor, highlighting the need for novel treatment options. Aberrant epigenetic regulation plays an important role in the pathogenesis of AML, and inhibitors of DNA methyltransferase or histone deacetylase (HDAC) enzymes have exhibited activity in preclinical AML models. Combination studies with HDAC inhibitors plus DNA methyltransferase inhibitors have potential beneficial clinical activity in AML, however the toxicity profiles of non-selective HDAC inhibitors in the combination setting limit their clinical utility. In this work, we describe the preclinical development of selective inhibitors of HDAC1 and HDAC2, which are hypothesized to have improved safety profiles, for combination therapy in AML. We demonstrate that selective inhibition of HDAC1 and HDAC2 is sufficient to achieve efficacy both as a single agent and in combination with azacitidine in preclinical models of AML, including established AML cell lines, primary leukemia cells from AML patient bone marrow samples and in vivo xenograft models of human AML. Gene expression profiling of AML cells treated with either an HDAC1/2 inhibitor, azacitidine, or the combination of both have identified a list of genes involved in transcription and cell cycle regulation as potential mediators of the combinatorial effects of HDAC1/2 inhibition with azacitidine. Together, these findings support the clinical evaluation of selective HDAC1/2 inhibitors in combination with azacitidine in AML patients.

Selective HDAC inhibition by ACY-241 enhances the activity of paclitaxel in solid tumor models.

ACY-241 is a novel, orally available and selective histone deacetylase (HDAC) 6 inhibitor in Phase 1b clinical development in multiple myeloma (NCT 02400242). Like the structurally related drug ACY-1215 (ricolinostat), ACY-241 has the potential for a substantially reduced side effect profile versus current nonselective HDAC inhibitor drug candidates due to reduced potency against Class I HDACs while retaining the potential for anticancer effectiveness. We now show that combination treatment of xenograft models with paclitaxel and either ricolinostat or ACY-241 significantly suppresses solid tumor growth. In cell lines from multiple solid tumor lineages, combination treatment with ACY-241 and paclitaxel enhanced inhibition of proliferation and increased cell death relative to either single agent alone. Combination treatment with ACY-241 and paclitaxel also resulted in more frequent occurrence of mitotic cells with abnormal multipolar spindles and aberrant mitoses, consistent with the observed increase of aneuploid cells. At the molecular level, multipolar mitotic spindle formation was observed to be NuMA-dependent and γ-tubulin independent, suggesting that treatment-induced multipolar spindle formation does not depend on centrosomal amplification. The significantly enhanced efficacy of ACY-241 plus paclitaxel observed here, in addition to the anticipated superior safety profile of a selective HDAC6 inhibitor versus pan-HDAC inhibitors, provides a strong rationale for clinical development of this combination in patients with advanced solid tumors.