Hepatocellular Carcinoma Tumor Burden Research Articles

Interleukin-1 receptor 1 deficiency worsens hepatocellular carcinoma, while gemcitabine treatment alleviates the hepatocellular carcinoma-induced increase in intra-hepatic immune cells.

Primary liver cancer, particularly hepatocellular carcinoma (HCC), represents a substantial global health challenge. Although immune checkpoint inhibitors are effective in HCC treatment, several patients still experience disease progression. Interleukin-1 (IL-1) regulates immunity and inflammation. We investigate the role of IL-1 in HCC development and progression and determine the potential therapeutic impact of gemcitabine in treating HCC. Hydrodynamics-based transfection, employing the sleeping beauty transposase system, delivered surrogate tumor antigens, NRAS (NRAS proto-oncogene, GTPase), ShP53, and SB100 to C57BL/6 mice. A basic HCC mouse model was established. Pathogen-free animals were tested for serum and hepatotoxicity. The HCC prognosis was monitored using alanine aminotransferase and aspartate aminotransferase levels. Liver histology immunohistochemistry and mouse splenocyte/intra-hepatic immune cell flow cytometry were conducted. IL-1β levels in human and mouse serum were assessed. Interleukin-1β levels were elevated in patients with HCC compared with those in non-HCC controls. Hepatic IL-1β levels were higher in HCC mouse models than those in non-HCC mice, suggesting localized hepatic inflammation. IL-1 receptor type 1 (IL-1R1) knockout (IL-1R1-/-) mice exhibited less severe HCC progression than that in wild-type mice, despite the high intra-hepatic IL-1β concentration. IL-1R1-/- mice exhibited increased hepatic levels of myeloid-derived suppressor cells and regulatory T cells, which may exacerbate HCC. Gemcitabine significantly reduced the HCC tumor burden, improved liver conditions, and increased survival rates in HCC mouse models. Gemcitabine reduced the hepatic levels of myeloid-derived suppressor cells and regulatory T cells, potentially alleviating immune suppression in the liver. Targeting IL-1 or combining gemcitabine with immunotherapy is a promising approach for treating advanced-stage HCC.

Identification of tumor mutations in plasma based on mutation variant frequency change (MVFC).

To overcome the dependency of strategies utilizing cell-free DNA (cfDNA) on tissue sampling, the emergence of sequencing panels for non-invasive mutation screening was promoted. However, cfDNA sequencing with panels still suffers from either inaccuracy or omission, and novel approaches for accurately screening tumor mutations solely based on plasma without gene panel restriction are urgently needed. We performed unique molecular identifier (UMI) target sequencing on plasma samples and peripheral blood mononuclear cells (PBMCs) from 85 hepatocellular carcinoma (HCC) patients receiving surgical resection, which were divided into an exploration dataset (20 patients) or an evaluation dataset (65 patients). Plasma mutations were identified in pre-operative plasma, and the mutation variant frequency change (MVFC) between post- and pre-operative plasma was then calculated. In the exploration dataset, we observed that plasma mutations with MVFC < 0.2 were enriched for tumor mutations identified in tumor tissues and had frequency changes that correlated with tumor burden; these plasma mutations were therefore defined as MVFC-identified tumor mutations. The presence of MVFC-identified tumor mutations after surgery was related to shorter relapse-free survival (RFS) in both datasets and thus indicated minimum residual disease (MRD). The combination of MVFC-identified tumor mutations and Alpha Fetoprotein (AFP) could further improve MRD detection (P < 0.0001). Identification of tumor mutations based on MVFC was also confirmed to be applicable with a different gene panel. Overall, we proposed a novel strategy for non-invasive tumor mutation screening using solely plasma that could be utilized in HCC tumor-burden monitoring and MRD detection.

P53-Bad* Fusion Gene Therapy Induces Apoptosis In Vitro and Reduces Zebrafish Tumor Burden in Hepatocellular Carcinoma.

With few curative treatments and a global yearly death rate of over 800,000, hepatocellular carcinoma (HCC) desperately needs new therapies. Although wild-type p53 gene therapy has been shown to be safe in HCC patients, it has not shown enough efficacy to merit approval. This work aims to show how p53 can be re-engineered through fusion to the pro-apoptotic BH3 protein Bcl-2 antagonist of cell death (Bad) to improve anti-HCC activity and potentially lead to a novel HCC therapeutic, p53-Bad*. p53-Bad* is a fusion of p53 and Bad, with two mutations, S112A and S136A. We determined mitochondrial localization of p53-Bad* in liver cancer cell lines with varying p53 mutation statuses via fluorescence microscopy. We defined the apoptotic activity of p53-Bad* in four liver cancer cell lines using flow cytometry. To determine the effects of p53-Bad* in vivo, we generated and analyzed transgenic zebrafish expressing hepatocyte-specific p53-Bad*. p53-Bad* localized to the mitochondria regardless of the p53 mutation status and demonstrated superior apoptotic activity over WT p53 in early, middle, and late apoptosis assays. Tumor burden in zebrafish HCC was reduced by p53-Bad* as measured by the liver-to-body mass ratio and histopathology. p53-Bad* induced significant apoptosis in zebrafish HCC as measured by TUNEL staining but did not induce apoptosis in non-HCC fish. p53-Bad* can induce apoptosis in a panel of liver cancer cell lines with varying p53 mutation statuses and induce apoptosis/reduce HCC tumor burden in vivo in zebrafish. p53-Bad* warrants further investigation as a potential new HCC therapeutic.

Radiofrequency Ablation versus Transarterial Chemoembolization for Hepatocellular Carcinoma within Milan Criteria: Prognostic Role of Tumor Burden Score.

Simple SummaryTumor burden score (TBS) has been recently introduced to assess the tumor burden in hepatocellular carcinoma (HCC), but its prognostic role in patients with early-stage HCC is unclear. We confirm that TBS is an independent prognostic predictor in HCC patients within the Milan criteria undergoing radiofrequency ablation (RFA) or transarterial chemoembolization (TACE). TACE may be an effective treatment alternative for these patients. Among patients with low TBS, RFA should be considered the priority treatment modality.Tumor burden score (TBS), estimated by the diameter and number of tumor nodules, was recently proposed to assess the tumor burden in hepatocellular carcinoma (HCC). We aimed to evaluate the prognostic impact of TBS on HCC patients within the Milan criteria undergoing radiofrequency ablation (RFA) or transarterial chemoembolization (TACE). A total of 883 patients undergoing RFA and TACE were included. The multivariate Cox proportional hazards model was used to determine independent prognostic predictors in different patient cohorts. The TACE group had significantly higher TBS compared with the RFA group. The RFA group had better long-term survival than the TACE group in patients within the Milan criteria in univariate survival analysis. In the Cox model, serum α-fetoprotein (AFP) > 20 ng/mL, performance status 1–2, medium and high TBS, albumin–bilirubin (ALBI) grade 2 and grade 3 were independent predictors linked with mortality (all p < 0.001). Overall, TACE was not an independent predictor; among patients with low TBS, TACE was independently associated with decreased survival compared with RFA (p = 0.034). Conclusions: TBS is a feasible prognostic marker for HCC patients within the Milan criteria. TACE may be an effective treatment alternative for these patients. Among patients with low TBS, RFA should be considered the priority treatment modality.

Optimal time point of response assessment for predicting survival is associated with tumor burden in hepatocellular carcinoma receiving repeated transarterial chemoembolization.

Objective response rate (ORR) under mRECIST criteria after transarterial chemoembolization (TACE) is a well-perceived surrogate endpoint of overall survival (OS). However, its optimal time point remains controversial and may be influenced by tumor burden. We aim to investigate the surrogacy of initial/best ORR in relation to tumor burden. A total of 1549 eligible treatment-naïve patients with unresectable hepatocellular carcinoma (HCC), Child-Pugh score ≤ 7, and performance status score ≤ 1 undergoing TACE between January 2010 and May 2016 from 17 academic hospitals were retrospectively analyzed. Based on "six-and-twelve" criteria, tumor burden was graded as low, intermediate, and high if the sum of the maximum tumor diameter and tumor number was ≤ 6, > 6 but ≤ 12, and > 12, respectively. Both initial and best ORRs interacted with tumor burden. Initial and best ORRs could equivalently predict and correlate with OS in low (adjusted HR, 2.55 and 2.95, respectively, both p < 0.001; R = 0.84, p = 0.035, and R = 0.97, p = 0.002, respectively) and intermediate strata (adjusted HR, 1.81 and 2.22, respectively, both p < 0.001; R = 0.74, p = 0.023, and R = 0.9, p = 0.002, respectively). For high strata, only best ORR exhibited qualified surrogacy (adjusted HR, 2.61, p < 0.001; R = 0.70, p = 0.035), whereas initial ORR was not significant (adjusted HR, 1.08, p = 0.357; R = 0.22, p = 0.54). ORR as surrogacy of OS is associated with tumor burden. For patients with low/intermediate tumor burden, initial ORR should be preferred in its early availability upon similar sensitivity, whereas for patients with high tumor burden, best ORR has optimal sensitivity. Timing of OR assessment should be tailored according to tumor burden. • This is the first study utilizing individual patient data to comprehensively analyze the surrogacy of ORR with a long follow-up period. • Optimal timing of ORR assessment for predicting survival should be tailored according to tumor burden. • For patients with low and intermediate tumor burden, initial ORR is optimal for its timeliness upon similar sensitivity with best ORR. For patients with high tumor burden, best ORR has optimal sensitivity.

Are Current National Review Board Downstaging Protocols for Hepatocellular Carcinoma Too Restrictive?

Liver transplantation (LT) is an effective strategy for patients with unresectable hepatocellular carcinoma (HCC). To qualify for standardized LT model for end-stage liver disease exception points, the United Network for Organ Sharing National Liver Review Board (NLRB) requires that the presenting and final HCC tumor burden be within the University of California San Francisco criteria, which were recently expanded (within expanded UCSF [W-eUCSF]). Current NLRB criteria may be too restrictive because it has been shown previously that the initial burden does not predict LT failure when tumors downstage to UCSF. This study aims to assess LT outcomes for HCC initially presenting beyond expanded UCSF (B-eUCSF) criteria in a large multicenter collaboration. Comparisons of B-eUCSF and W-eUCSF candidates undergoing LT at seven academic institutions between 2001 and 2017 were made from a multi-institutional database. Survival outcomes were compared by Kaplan-Meier and Cox regression analyses. Of 1,846 LT recipients with HCC, 86 (5%) met B-eUCSF criteria at initial presentation, with the remainder meeting W-eUCSF criteria. Despite differences in tumor burden, B-eUCSF candidates achieved comparable 1-, 5- and 10-year overall (89%, 70%, and 55% vs 91%, 74%, and 60%, respectively; p = 0.2) and disease-free (82%, 60%, and 53% vs 89%, 71%, and 59%, respectively; p = 0.07) survival to patients meeting W-eUCSF criteria after LT. Despite increased tumor recurrence in B-eUCSF vs W-eUCSF patients (24% vs 10%, p = 0.0002), post-recurrence survival was similar in both groups (p = 0.69). Transplantation for patients initially presenting with HCC B-eUSCF criteria offers a survival advantage similar to those with tumors meeting W-eUCSF criteria at presentation. The current NLRB policy is too stringent, and considerations to expand criteria should be discussed.

Tumor burden score as a new prognostic marker for patients with hepatocellular carcinoma undergoing transarterial chemoembolization.

Size and number are major determinants of tumor burden in hepatocellular carcinoma (HCC). Patients with HCC undergoing transarterial chemoembolization (TACE) have variable outcomes due to heterogeneity of tumor burden. Recently, tumor burden score (TBS) was proposed to evaluate the extent of tumor involvement. However, the prognostic accuracy of TBS has not been well evaluated in HCC. This study aimed to assess its prognostic role in HCC patients undergoing TACE. A total of 935 treatment-naïve HCC patients receiving TACE were retrospectively analyzed. Multivariate Cox proportional hazards model was used to determine independent prognostic predictors. Tumor burden score tended to increase with increasing size and number of tumors in study patients. The Cox model showed that serum creatinine≥1.2mg/dL (hazard ratio [HR]: 1.296, 95% confidence interval [CI]: 1.077-1.559, P=0.006), serum α-fetoprotein≥400ng/dL (HR: 2.245, 95% CI: 1.905-2.645, P<0.001), vascular invasion (HR: 1.870, 95% CI: 1.520-2.301, P<0.001), medium TBS (HR: 1.489, 95% CI: 1.206-1.839, P<0.001) and high TBS (HR: 2.563, 95% CI: 1.823-3.602, P<0.001), albumin-bilirubin (ALBI) grade 2-3 (HR: 1.521, 95% CI: 1.291-1.792, P<0.001), and performance status 1 (HR: 1.362, 95% CI: 1.127-1.647, P<0.001) and status 2 (HR: 1.553, 95% CI: 1.237-1.948, P<0.001) were associated with increased mortality. Patients with high TBS had poor overall survival in Barcelona Clinic Liver Cancer stage B/C and different ALBI grades. Tumor burden score is a feasible new prognostic surrogate marker of tumor burden in HCC and can well discriminate survival in patients undergoing TACE across different baseline characteristics.

Overall Tumor Burden Dictates Outcomes for Patients Undergoing Resection of Multinodular Hepatocellular Carcinoma Beyond the Milan Criteria.

The objective of the current study was to define surgical outcomes after resection of multinodular hepatocellular carcinoma (HCC) beyond the Milan criteria, and develop a prediction tool to identify which patients likely benefit the most from resection. Liver resection for multinodular HCC, especially beyond the Milan criteria, remains controversial. Rigorous selection of the best candidates for resection is essential to achieve optimal outcomes after liver resection of advanced tumors. Patients who underwent resection for HCC between 2000 and 2017 were identified from an international multi-institutional database. Patients were categorized according to Milan criteria status. Pre- and postoperative overall survival (OS) prediction models that included HCC tumor burden score (TBS) among patients with multinodular HCC beyond Milan criteria were developed and validated. Among 1037 patients who underwent resection for HCC, 164 (15.8%) had multinodular HCC beyond the Milan criteria. Among patients with multinodular HCC, 25 (15.2%) patients experienced a serious complication and 90-day mortality was 3.7% (n = 6). Five-year OS after resection of multinodular HCC beyond Milan criteria was 52.8%. A preoperative TBS-based model (5-year OS: low-risk, 73.7% vs intermediate-risk, 45.1% vs high-risk, 13.1%), and postoperative TBS-based model (5-year OS: low-risk, 80.1% vs intermediate-risk, 37.2% vs high-risk, not reached) categorized patients into distinct prognostic groups relative to long-term prognosis (both P < 0.001). Pre- and postoperative models could accurately stratify OS in an external validation cohort (5-year OS; low vs medium vs high risk; pre: 66.3% vs 25.2% vs not reached, P = 0.012; post: 61.4% vs 42.5% vs not reached, P = 0.045) Predictive accuracy of the pre- and postoperative models was good in the training (c-index; pre: 0.68; post: 0.71), internal validation (n = 2000 resamples) (c-index, pre: 0.70; post: 0.72) and external validation (c-index, pre: 0.67; post 0.68) datasets. TBS alone could stratify patients relative to 5-year OS after resection of multinodular HCC beyond Milan criteria (c-index: 0.65; 5-year OS; low TBS: 70.2% vs medium TBS: 54.7% vs high TBS: 16.7%; P < 0.001). The vast majority of patients with low and intermediate TBS were deemed low or medium risk based on both the preoperative (98.4%) and postoperative risk scores (95.3%). Prognosis of patients with multinodular HCC was largely dependent on overall tumor burden. Liver resection should be considered among patients with multinodular HCC beyond the Milan criteria who have a low- or intermediate-TBS.

AS149 - Optimal time-point of response assessment for predicting survival is associated with tumor burden in hepatocellular carcinoma receiving repeated transarterial chemoembolization

AS149 - Optimal time-point of response assessment for predicting survival is associated with tumor burden in hepatocellular carcinoma receiving repeated transarterial chemoembolization

Recurrence beyond the Milan criteria after curative-intent resection of hepatocellular carcinoma: A novel tumor-burden based prediction model.

Accurate prediction of recurrence patterns of hepatocellular carcinoma (HCC) may allow for prioritization of patients for resection or transplantation as well as guide post-resection surveillance strategies. Patients who underwent curative-intent R0 resection for HCC between 2000 and 2017 were identified using a multi-institutional database. A prognostic model that incorporated HCC tumor burden score (TBS) to predict recurrence beyond the Milan criteria (MC) was developed and validated. Among 718 patients who underwent R0 resection for HCC, 185 (25.8%) recurred within and 110 (15.3%) beyond the MC. On multivariable analysis, AFP more than 400 ng/mL (hazard ratio [HR] = 2.26; 95% confidence interval [CI]: 1.27-4.02), lymphovascular invasion (HR = 2.00; 95% CI: 1.14-3.50), and TBS (HR = 1.08; 95% CI: 1.03-1.12) were associated with recurrence beyond the MC. A weighted TBS-based score was constructed: [0.074*TBS + 0.692*lymphovascular invasion (yes: 1, no: 0) + 0.816*AFP > 400 (yes:1, no:0)]. Patients with a low, medium, and high TBS-based risk score had a 5-year incidence of recurring beyond the MC of 16.2%, 28.6%, and 47.2%, respectively (P < .001). The predictive accuracy of the model was very good in the training (C-index: 0.761) and validation (C-index: 0.706) datasets and outperformed the previously reported clinical risk score (CRS; C-index: 0.680). A TBS-based model accurately predicted recurrence beyond MC after curative-intent resection of HCC and outperformed the CRS. Incorporating TBS allows for better risk stratification and identifies patients in need of closer surveillance.

AGA Clinical Practice Update on Interaction Between Oral Direct-Acting Antivirals for Chronic Hepatitis C Infection and Hepatocellular Carcinoma: Expert Review.

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Validation of miR-20a as a Tumor Suppressor Gene in Liver Carcinoma Using Hepatocyte-Specific Hyperactive piggyBac Transposons

We established a semi-high-throughput in vivo screening platform using hyperactive piggyBac (hyPB) transposons (designated as PB-miR) to identify microRNAs (miRs) that inhibit hepatocellular carcinoma (HCC) development in vivo, following miR overexpression in hepatocytes. PB-miRs encoding six different miRs from the miR-17-92 cluster and nine miRs from outside this cluster were transfected into mouse livers that were chemically induced to develop HCC. In this slow-onset HCC model, miR-20a significantly inhibited HCC. Next, we developed a more aggressive HCC model by overexpression of oncogenic Harvey rat sarcoma viral oncogene homolog (HRASG12V) and c-MYC oncogenes that accelerated HCC development after only 6 weeks. The tumor suppressor effect of miR-20a could be demonstrated even in this rapid-onset HRASG12V/c-MYC HCC model, consistent with significantly prolonged survival and decreased HCC tumor burden. Comprehensive RNA expression profiling of 95 selected genes typically associated with HCC development revealed differentially expressed genes and functional pathways that were associated with miR-20a-mediated HCC suppression. To our knowledge, this is the first study establishing a direct causal relationship between miR-20a overexpression and liver cancer inhibition in vivo. Moreover, these results demonstrate that hepatocyte-specific hyPB transposons are an efficient platform to screen and identify miRs that affect overall survival and HCC tumor regression.

Comprehensive Liquid Profiling of Circulating Tumor DNA and Protein Biomarkers in Long-Term Follow-Up Patients with Hepatocellular Carcinoma

Circulating tumor DNA (ctDNA) provides a novel approach for detecting tumor burden and predicting clinical outcomes of hepatocellular carcinoma (HCC). Here, we performed a thorough evaluation of HCC circulating genetic features and further fully integrated them to build a robust strategy for HCC monitoring and prognostic outcome assessment. We performed target sequencing and low-coverage whole-genome sequencing on plasma samples collected from 34 long-term follow-up patients with HCC to capture tumor somatic SNVs and CNVs, respectively. Clinical information was also obtained to evaluate the prognostic performance of ctDNA comparing with clinically applied protein biomarkers. All plasma samples before surgery showed somatic genetic variations resembling corresponding tumor tissues. During follow-up, SNVs and CNVs dynamically changed correlating to patients' tumor burden. We integrated the comprehensive ctDNA mutation profiles to provide a robust strategy to accurately assess patients' tumor burden with high consistence comparing with imaging results. This strategy could discover tumor occurrence in advance of imaging for an average of 4.6 months, and showed superior performance than serum biomarkers AFP, AFP-L3%, and Des-Gamma-Carboxy Prothrombin (DCP). Furthermore, our strategy could precisely detect minimal residual disease (MRD) in advance and predict patients' prognostic outcomes for both relapse-free survival (P = 0.001) and overall survival (P = 0.001); further combining ctDNA with DCP could increase the sensitivity for MRD detection. We demonstrated that plasma CNV and SNV levels dynamically correlated with patients' tumor burden in HCC. Our strategy of comprehensive mutation profile integration could accurately and better evaluate patients' prognostic risk and detect tumor occurrence in advance than traditional strategies.

Bioengineered Let-7c Inhibits Orthotopic Hepatocellular Carcinoma and Improves Overall Survival with Minimal Immunogenicity

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related deaths, warranting better therapies. Restoration of tumor-suppressive microRNAs depleted in hepatocellular carcinoma represents a new therapeutic strategy. Herein, we sought to identify a potent microRNA (miRNA) agent that could alleviate HCC tumor burden and improve survival. Among a collection of bioengineered noncoding RNA molecules produced through bacterial fermentation, we identified let-7c agent as the most potent inhibitor of HCC cell viability. Bioengineered let-7c selectively modulated target gene expression (Lin-28 homolog B [LIN28B], AT-rich interactive domain-containing protein 3B [ARID3B], B cell lymphoma-extra large [Bcl-xl], and c-Myc) in HCC cells, and consequently induced apoptosis and inhibited tumorsphere growth. When formulated with liposomal-branched polyethylenimine polyplex, bioengineered let-7c exhibited serum stability up to 24 h. Furthermore, liposomal polyplex-formulated let-7c could effectively reduce tumor burden and progression in orthotopic HCC mouse models, while linear polyethyleneimine-formulated let-7c to a lower degree, as revealed by live animal and ex vivo tissue imaging studies. This was also supported by reduced serum α-fetoprotein and bilirubin levels in let-7c-treated mice. In addition, lipopolyplex-formulated let-7c extended overall survival of HCC tumor-bearing mice and elicited no or minimal immune responses in healthy immunocompetent mice and human peripheral blood mononuclear cells. These results demonstrate that bioengineered let-7c is a promising molecule for advanced HCC therapy, and liposomal polyplex is a superior modality for in vivo RNA delivery.

Dynamical detection and characterization of circulating tumor DNA in patients with hepatocellular carcinoma

Introduction: Circulating tumor DNA (ctDNA) provides a novel approach for detecting tumor burden and predicting clinical outcomes of hepatocellular carcinoma (HCC). Here we performed a thorough evaluation of HCC circulating genetic features and further fully integrated them to build a robust strategy for HCC surveillance and prognostic outcome assessment. Method: We performed target sequencing and low coverage whole genome sequencing on 168 plasma samples collected from 34 long-term follow-up HCC patients to capture tumor somatic SNVs and CNVs, respectively. Clinical information was also obtained to evaluate the prognostic performance of ctDNA comparing with clinically applied protein biomarkers. Result: All plasma samples before surgery showed somatic genetic variations resembling corresponding tumor tissues. During follow-up, SNVs and CNVs dynamically changed correlating to patients’ tumor burden. We integrated the comprehensive ctDNA mutation profiles to provide a robust strategy to accurately assess patients’ tumor burden with high consistence comparing to imaging results. This strategy could discover tumor occurrence in advance of imaging for an average of 4.6 months, and showed superior performance than serum biomarkers AFP, AFP-L3% and DCP. Furthermore, our strategy could precisely detect MRD in advance and predict patients’ prognostic outcomes for both RFS (p=0.001) and OS (p=0.001); further combining ctDNA with DCP could increase the sensitivity for MRD detection. Conclusion: We demonstrated that plasma CNV and SNV levels dynamically correlated with patients’ tumor burden in HCC. Our strategy of comprehensive mutation profile integration could accurately and better evaluate patients’ prognostic risk and detect tumor occurrence in advance than traditional strategies.

Abstract 2917: Differentiation therapy and the mechanisms that terminate malignant proliferation

Abstract Historically, chemotherapy often attempts to activate apoptosis in tumor cells even when master regulators of apoptosis (e.g., TP53) are inactivated by genetic mutations, leading to multi-drug resistance. A potential form of non-toxic therapy is to engage p53-independent terminal differentiation. Exponential proliferation in lineage committed progenitors, coordinated by the transcription factor MYC, is succeeded by terminal differentiation, whereas MYC-coordinated aberrant proliferation in human malignancies is not succeeded by terminal differentiation. The mechanisms that suppress terminal differentiation are mostly unclear, impeding development of differentiation therapies. We performed a systematic review of published literature between January 2007 – January 2017 to identify genetic alterations that produce candidate molecular targets for differentiation induction in three treatment-recalcitrant cancers: hepatocellular carcinoma (HCC), ovarian cancer (OVC) and pancreatic ductal adenocarcinoma (PDAC). We then validated candidate molecular targets in-vitro with FANA molecules and CRISPR-Cas9, and by in-vivo validation of small molecule drugs in HCC. By systematic review, lineage tracing studies suggested master transcription factors of cell fate and their cofactors as links to suppression of cell cycle exit by differentiation. Indeed, sequence analysis of HCC, OVC and PDAC identified frequent genetic haploinsufficiency in lineage transcription factors (e.g., GATA4 67% hetloss HCC, n=442, FOXO1 63% hetloss, OVC n=302, PDX1 58% hetloss, PDAC n=109), while their coactivators (e.g. ARID1A/B, and ARID3A/C) were frequently inactivated by genetic mutation/deletion. Interestingly, corepressors (e.g., DNMT1, EED, BAZ1A/B, and SUZ12) that cooperate with these transcription factors to turn off genes were frequently amplified but not inactivated. By immunoprecipitation and mass spectroscopy, we identified in HCC that corepressors (e.g., DNMT1) were aberrantly recruited to wild-type hepatocyte transcription factors (FOXA1/2) and this interaction epigenetically suppressed hepatocyte differentiation genes (e.g., HNF4A). Pre-clinical trials evaluating DNMT1 therapeutic efficacy - by DNMT1-FANA or DNMT1-CRISPR-Cas9 - suppressed HCC proliferation but increased hepatocyte differentiation. Non-cytotoxic treatment (0.2µM) of decitabine (DEC) - DNMT1 inhibitor - terminated HCC proliferation without inducing apoptosis. This inhibition enhanced FOXA1/2 interaction with coactivators, decreased corepressors, increased hepatocyte differentiation by decreasing MYC protein, increasing p27 protein and activating HNF4A. Using 0.2mg/Kg of DEC in vivo - in obesity induced mouse model of HCC - DEC reduced HCC tumor burden, without apoptosis induction. Thus, aberrant corepressors are rational molecular targets that engage terminal differentiation in cancer cells. Citation Format: Francis O. Enane, Xiaorong Gu, Murray Korc, Yogen Saunthararajah. Differentiation therapy and the mechanisms that terminate malignant proliferation [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 2917.

Abstract 1334: Withaferin A induces cytoprotective autophagy in hepatocellular cancer cells and concomitant autophagic inhibition augments the efficacy of Withaferin A in hepatocellular carcinoma

Abstract Background and Aim: Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world and the third most common cause of cancer-related deaths. While multiple chemotherapeutic and targeted agents have been developed for other cancers, Sorafenib, an oral multikinase inhibitor, is the only approved agent for the treatment of advanced HCC. Clearly, it is imperative to develop novel effective therapeutic strategies for HCC to improve long-term survival of HCC patients. We found Withaferin A (WFA), a bioactive alkaloid derived from Withania somnifera, as an effective agent for HCC inhibition. Interestingly, we observed that WFA also induces autophagy in HCC cells. Autophagy can be cancer inducing or cancer inhibiting at the functional level. We aim to systemically investigate the anti-HCC efficacy of WFA, investigate the functional impact of autophagy and explore the efficacy of combined regimens of WFA and autophagic inhibitors. Methods: Using in vitro and in vivo models, we established that WFA inhibits liver tumorigenesis. tfLC3B, LC3B-GFP/Lysotracker and LC3B/Rab7 were used to examine the fusion of autophagosomes with lysosomes. Cathepsin-D activation and DQ-BSA assays were conducted to analyze the protein degradation activity in lysosomes. Multiple cell based assays and Chou-Talalay synergy quantification assays were conducted to analyze the synergistic effect of WFA with autophagic inhibitors. IHC staining was used to study autophagic markers in vivo. Results: WFA inhibited anchorage dependent cell growth in vitro and reduced the HCC tumor burden in vivo. In addition to inducing apoptotic cell death, WFA induced cleavage of Light Chain 3B (LC3B) and increased the expression of autophagic proteins (ATG5, ATG7 and Beclin1) both in vitro and in vivo. The redistribution of LC3B-GFP from cytosol to autophagosome demonstrated enhanced autophagosome formation in WFA treated cells. The fusion of autophagosome with lysosome was observed in WFA-treated HCC cells indicating autolysosome formation. WFA treated HCC cells exhibited elevated lysosomal degradation activity. Inhibiting autophagy either by blocking autophagosome formation or elevating lysosomal pH (CQ and BAF) enhanced WFA-induced growth inhibition and apoptosis indicating the presence of cytoprotective autophagy. Combination index analysis of WFA and CQ showed synergism and increased efficacy as compared to either monotherapy. These in vitro findings were corroborated with in vivo experiments. Conclusion: Our results reveal that WFA inhibits hepatocellular carcinoma by apoptotic induction but the efficacy of WFA is somewhat abrogated by the concomitant induction of cytoprotective autophagy. Our preclinical findings present evidence to support WFA and chloroquine as an effective combination treatment regimen for HCC. Citation Format: Sumit Siddharth, Nethaji Muniraj, Neeraj K. Saxena, Dipali Sharma. Withaferin A induces cytoprotective autophagy in hepatocellular cancer cells and concomitant autophagic inhibition augments the efficacy of Withaferin A in hepatocellular carcinoma [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 1334.

Decreased hepatocellular carcinoma tumor burden with the achievement of hepatitis C virus sustained virologic response: unlocking the potential of T-cell-mediated immunosurveillance.

We describe two cases of patients with hepatitis C virus (HCV) treated with direct-acting antiviral (DAA) therapy who had dramatic improvement in hepatocellular carcinoma (HCC) tumor burden with DAA therapy alone. Both patients were diagnosed with HCC on screening magnetic resonance imaging shortly after beginning DAA therapy. Both patients achieved sustained virologic response (SVR) with dramatic improvement in HCC tumor burden on follow-up imaging without HCC treatment. Patients with multifocal or advanced HCC are infrequently treated with antiviral therapy for HCV. As a result, these cases provide unique insight into the ongoing debate regarding the impact of SVR on existing and recurrent HCC. We review the current literature regarding this debate, as well as the theory of immunosurveillance. We postulate that DAA therapy activates CD8+ T cells to induce a T-cell-mediated response and increased immunosurveillance to virus-induced liver cancer.

Bioengineered let‐7c is Effective at Reducing Orthotopic Hepatocellular Carcinoma Tumor Burden and is Well Tolerated in Mouse Models

Given pleiotropic molecular targeting mechanisms, restoration or inhibition of endogenous microRNAs (miRNA) is a promising pharmacological strategy. Recently, our group has bioengineered a collection of miRNA agents in live cells using a non‐coding carrier RNA (nCAR) based technology. In vitro screening identified nCAR/let‐7c as the most potent at inhibiting hepatocellular carcinoma (HCC) viability; this was found to be processed to the mature let‐7c molecule and suppressed target gene expression. As such, in vivo efficacy and safety of this agent was characterized in the present study using polyethyleneimine (PEI) and liposomal‐polyplex (LPP) RNA formulations. Huh7 cells stably expressing luciferase and green fluorescent protein were orthotopically engrafted into immunocompromised mice. To evaluate efficacy, 40 μg of nCAR/let‐7c or a truncated control agent was administered systemically every‐other day for two weeks, followed immediately by necropsy. Live animal bioluminescent and ex vivo fluorescent imaging suggested that LPP‐formulated nCAR/let‐7c reduced tumor burden to a greater degree than all controls and PEI‐formulated nCAR/let‐7c. Additionally, both nCAR/let‐7c and truncated control agents were well‐tolerated compared to untreated mice, as evidenced by gross evaluation and similar bodyweights throughout the study; however, further studies are warranted in immunocompetent animal models to elucidate the complete toxicological profile and immunogenic potential of nCAR/let‐7c. These data are the first to demonstrate that let‐7c restoration using a biologically‐derived agent can serve as a potent antineoplastic agent, presenting a new, clinically‐relevant strategy for HCC therapy.Support or Funding InformationThis work was supported by National Institutes of Health grants [R01GM113888 and U01CA175315 to A.‐M.Y.] and an institutional Pharmacology Training Program grant [T32GM099608 to J.L.J.].This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Simultaneous inhibition of growth and metastasis of hepatocellular carcinoma by co-delivery of ursolic acid and sorafenib using lactobionic acid modified and pH-sensitive chitosan-conjugated mesoporous silica nanocomplex

Co-delivery multiple drugs using nanocarriers has been recognized as a promising strategy for cancer treatment to enhance therapeutic efficacy. In this study, a pH sensitive mesoporous silica nanoparticles (MSN) based controlled release nanoparticles for co-delivery of sorafenib (SO), a multi-tyrosine kinase inhibitor, and ursolic acid (UA), a sensitive agent for SO, was developed, which was decorated with pH sensitive chitosan (CS) and lactobionic acid (LA) targeting to asialoglycoprotein receptor (ASGPR) over-expressing hepatocellar carcinoma cells (denoted as USMNs-CL). The nanocomplex enhanced bioavailability of hydrophobic drugs, efficient tumor cell targeting and exhibited pH-responsive function and sustained release profile. USMNs-CL showed synergistic cytotoxicity and could attenuate the adhesion, migration of ASGPR over-expressing liver cancer SMMC-7721cells at non-toxic concentrations. Moreover, the complex nanoparticles significantly increased the cellular apoptosis and down-regulated the expression of EGFR and VEGFR2 proteins related with cell proliferation and tumor angiogenesis. Invivo, compared with UA or SO alone, the nanocomplex significantly reduced the tumor burden in hepatocellular carcinoma (HCC) H22 tumor-bearing mice model and inhibited the lung metastasis in the H22 lung metastasis models. Overall, co-delivery of UA and SO by MSN-CS-LA nanocarriers could provide a promising strategy for HCC combinational therapy, especially for the HCC metastasis chemoprevention.