Potential synergistic anti-tumor activity between lenalidomide and sorafenib in hepatocellular carcinoma

Partial response of hepatocellular carcinoma to lenalidomide following progression in response to lenvatinib: A case report

Hepatocellular carcinoma (HCC) is one of the most aggressive types of cancer. Although it has a high mortality rate, there is currently no effective treatment for HCC. Lenvatinib has traditionally been used as the first-line treatment for advanced HCC (aHCC); however, resistance to this therapy is common. It can be difficult to select effective second-line drugs to overcome lenvatinib resistance when treating aHCC. For patients with aHCC, poor treatment efficacy can result in patients missing the optimal treatment window and can lead to an irreversible situation. Lenalidomide has begun to be used to treat HCC; however, to the best of our knowledge, its efficacy in patients with lenvatinib-resistant HCC remains to be reported on in the literature. The present case report, to the best of our knowledge, describes the first case in the literature of a patient with lenvatinib-resistant aHCC who achieved a partial response after the treatment regimen was switched to lenalidomide. The present case report provides a promising novel route for the treatment of lenvatinib-resistant HCC.

Venetoclax Overcomes Sorafenib Resistance in Acute Myeloid Leukemia by Targeting BCL2

Sorafenib, a kinase inhibitor, has shown promising therapeutic efficacy in a subset of patients with acute myeloid leukemia (AML). However, despite its clinical effectiveness, sorafenib resistance is frequently observed in clinical settings, and the mechanisms underlying this resistance as well as effective strategies to overcome it remain unclear. We examined both single-cell and bulk transcription data in sorafenib-resistant and control AML patients and integrated a sorafenib resistance gene signature to predict the sensitivity of AML cells and the clinical outcomes of AML patients undergoing sorafenib therapy. In addition, our drug sensitivity analysis of scRNA-seq data using deconvolution methods showed that venetoclax was effective in targeting sorafenib-resistant AML cells. Mechanistically, sorafenib was found to activate the JAK-STAT3 pathway and upregulate BCL2 expression in sorafenib-resistant AML cells. This upregulation of BCL2 expression rendered the cells vulnerable to the BCL2 inhibitor venetoclax. In conclusion, we developed a platform to predict sorafenib resistance and clinical outcomes in AML patients after therapy. Our findings suggest that the combination of sorafenib and venetoclax could be an effective therapeutic strategy for AML treatment.

Repurposing cabozantinib with therapeutic potential in KIT-driven t(8;21) acute myeloid leukaemias

Cabozantinib is an orally available, multi-target tyrosine kinase inhibitor approved for the treatment of several solid tumours and known to inhibit KIT tyrosine kinase. In acute myeloid leukaemia (AML), aberrant KIT tyrosine kinase often coexists with t(8;21) to drive leukaemogenesis. Here we evaluated the potential therapeutic effect of cabozantinib on a selected AML subtype characterised by t(8;21) coupled with KIT mutation. Cabozantinib exerted substantial cytotoxicity in Kasumi-1 cells with an IC₅₀ of 88.06 ± 4.32 nM, which was well within clinically achievable plasma levels. The suppression of KIT phosphorylation and its downstream signals, including AKT/mTOR, STAT3, and ERK1/2, was elicited by cabozantinib treatment and associated with subsequent alterations of cell cycle- and apoptosis-related molecules. Cabozantinib also disrupted the synthesis of an AML1-ETO fusion protein in a dose- and time-dependent manner. In a mouse xenograft model, cabozantinib suppressed tumourigenesis at 10 mg/kg and significantly prolonged survival of the mice. Further RNA-sequencing analysis revealed that mTOR-mediated signalling pathways were substantially inactivated by cabozantinib treatment, causing the downregulation of ribosome biogenesis and glycolysis, along with myeloid leukocyte activation. We suggest that cabozantinib may be effective in the treatment of AML with t(8;21) and KIT mutation. Relevant clinical trials are warranted.

Mouse Models for Immunotherapy in Hepatocellular Carcinoma

Liver cancer is one of the dominant causes of cancer-related mortality, and the survival rate of liver cancer is among the lowest for all cancers. Immunotherapy for hepatocellular carcinoma (HCC) has yielded some encouraging results, but the percentage of patients responding to single-agent therapies remains low. Therefore, potential directions for improved immunotherapies include identifying new immune targets and checkpoints and customizing treatment procedures for individual patients. The development of combination therapies for HCC is also crucial and urgent and, thus, further studies are required. Mice have been utilized in immunotherapy research due to several advantages, for example, being low in cost, having high success rates for inducing tumor growth, and so on. Moreover, immune-competent mice are used in immunotherapy research to clarify the role that the immune system plays in cancer growth. In this review paper, the advantages and disadvantages of mouse models for immunotherapy, the equipment that are used for monitoring HCC, and the cell strains used for inducing HCC are reviewed.

A Novel Drug, CC-122, Inhibits Tumor Growth in Hepatocellular Carcinoma through Downregulation of an Oncogenic TCF-4 Isoform

Immunomodulatory drugs such as lenalidomide (LEN) have shown significant anti-tumor activity against hematologic malignancies and they may have similar actions on solid tumors as well. We studied the effect of a new analog of the immunomodulatory drugs (CC-122) on the growth of hepatocellular carcinoma (HCC) and explored mechanisms of anti-tumor activity by analyzing expression of a novel oncogenic T-cell factor (TCF)-4 J and its downstream gene activation. LEN and CC-122 significantly reduced the expression levels of TCF-4 J and its target genes (SPP1, AXIN2, MMP7, ASPH, CD24, ANXA1, and CAMK2N1); however, CC-122 was more potent. In a xenograft tumor model with a HAK-1A-TCF-4 J derived stable cells, tumor growth was significantly inhibited by CC-122, but not by LEN or vehicle control. The mice with HCC xenograft tumors treated with CC-122 exhibited decreased TCF-4 J expression compared to LEN and control. Furthermore, expression of TCF-4 J-responsive target genes (SPP1, AXIN2, MMP7, ASPH, JAG1, CD24, ANXA1, and CAMK2N1) was reduced by CC-122 and not by LEN or control. These results suggest that CC-122 inhibits HCC tumor growth through downregulation of the oncogenic TCF-4 J isoform.

Development of a PD-L1-Expressing Orthotopic Liver Cancer Model: Implications for Immunotherapy for Hepatocellular Carcinoma

BACKGROUND

Anti-programmed cell death-1(anti-PD1) treatment has shown promising antitumor efficacy in patients with advanced hepatocellular carcinoma (HCC). This study sought to explore the functional significance of programmed death ligand-1 (PD-L1) expression in tumor cells in the tumor microenvironment.

METHODS

The mouse liver cancer cell line BNL-MEA was transfected with PD-L1 plasmids and stable clones expressing PD-L1 were selected. An orthotopic HCC model was generated by implanting the cells into the subcapsular space of BALB/c mice. Cell growth features were measured by proliferation assay, colony formation, flow cytometry (in vitro), ultrasonography, and animal survival (in vivo). The changes in T-cell function were examined by cytokine assay, expression of T-cell related genes, and flow cytometry. The efficacy of anti-PD1 therapy was compared between the parental and PD-L1-expressing tumors.

RESULTS

PD-L1 expression did not affect growth characteristics of BNL-MEA cells but downregulated the expression of genes related to T-cell activation in the tumor microenvironment. Co-culture of PD-L1-expressing BNL-MEA cells with CD8+ T cells reduced T-cell proliferation and expression of cytokines IFNγ and TNFα. Tumors with PD-L1 expression showed better response to anti-PD1 therapy and depletion of CD8+ T cells abolished the antitumor effect. The difference in treatment response between parental and PD-L1-expressing tumors disappeared when a combination of anti-PD1 and sorafenib was given.

CONCLUSIONS

PD-L1 expression in HCC cells may inhibit T-cell function in the liver tumor microenvironment. Anti-PD1 therapy appeared more effective in PD-L1-expressing than nonexpressing tumors, but the difference was diminished by the addition of sorafenib.

TNF-α is a potential therapeutic target to overcome sorafenib resistance in hepatocellular carcinoma

Background

The role of tumor necrosis factor alpha (TNF-α) in targeted therapy for hepatocellular carcinoma (HCC) remains largely unknown. The current study aimed to clarify the mechanistic effects of targeting TNF-α to overcome sorafenib resistance in HCC.

Methods

A correlation of TNF-α expression with the prognosis was analyzed in 62 HCC patients who underwent surgical resection and subsequent received adjuvant sorafenib treatment. The relation of TNF-α expression and sorafenib sensitivity was determined in different HCC cell lines. The combined therapeutic effects of sorafenib and ulinastatin, which could inhibit TNF-α expression, on HCC were examined in vitro and in vivo.

Findings

High TNF-α expression was correlated with poor outcomes in HCC patients who received adjuvant sorafenib after surgery. In vitro experiments showed that TNF-α promotes HCC cell resistant to sorafenib through inducing epithelial-mesenchymal transition (EMT). Notably, the current study revealed that sorafenib has no significant influence on the expression and secretion of TNF-α, and sorafenib had limited effectiveness on reversing EMT in HCC cells with high TNF-α expression. Inhibiting the expression of TNF-α with ulinastatin significantly enhanced the anti-tumor effect of sorafenib on HCC cells with high expression of TNF-α in vitro and in vivo.

Interpretation: Our findings indicate that TNF-α may serve as a novel predictor of sorafenib sensitivity in HCC patients. Sorafenib combined with ulinastatin may improve the effectiveness of treatment of HCC in patients with high expression of TNF-α.

Fund

This work was supported by grants from the National Natural Science Foundation of China (no.81572398; no.81672419), the Science and Technology Planning Project of Guangdong Province (no. 2017A010105003; no.2015A050502023; no.2016A020216010), and the Natural Science Foundation of Guangdong Province (no.2014A030313061; no. 2013B021800101).

How to Hit Mesenchymal Stromal Cells and Make the Tumor Microenvironment Immunostimulant Rather Than Immunosuppressive

Experimental evidence indicates that mesenchymal stromal cells (MSCs) may regulate tumor microenvironment (TME). It is conceivable that the interaction with MSC can influence neoplastic cell functional behavior, remodeling TME and generating a tumor cell niche that supports tissue neovascularization, tumor invasion and metastasization. In addition, MSC can release transforming growth factor-beta that is involved in the epithelial-mesenchymal transition of carcinoma cells; this transition is essential to give rise to aggressive tumor cells and favor cancer progression. Also, MSC can both affect the anti-tumor immune response and limit drug availability surrounding tumor cells, thus creating a sort of barrier. This mechanism, in principle, should limit tumor expansion but, on the contrary, often leads to the impairment of the immune system-mediated recognition of tumor cells. Furthermore, the cross-talk between MSC and anti-tumor lymphocytes of the innate and adaptive arms of the immune system strongly drives TME to become immunosuppressive. Indeed, MSC can trigger the generation of several types of regulatory cells which block immune response and eventually impair the elimination of tumor cells. Based on these considerations, it should be possible to favor the anti-tumor immune response acting on TME. First, we will review the molecular mechanisms involved in MSC-mediated regulation of immune response. Second, we will focus on the experimental data supporting that it is possible to convert TME from immunosuppressive to immunostimulant, specifically targeting MSC.

Lenalidomide as second-line therapy for advanced hepatocellular carcinoma: exploration of biomarkers for treatment efficacy

BACKGROUND

Lenalidomide has immunomodulatory and anti-angiogenic effects and showed moderate anti-tumour efficacy in patients with. advanced hepatocellular carcinoma (HCC) AIM: To explore potential biomarkers of lenalidomide efficacy as second-line therapy for HCC.

METHODS

Eligible patients were diagnosed with advanced HCC, documented progression on sorafenib, and Child-Pugh class A liver function. Patients received 25 mg/day lenalidomide orally on days 1-21 every 4 weeks. The primary endpoint was 6 month progression-free survival rate. Early α-fetoprotein response was defined as a > 20% decline of α-fetoprotein levels from baseline within the first 4 weeks of treatment. Vascular response, evaluated using dynamic contrast-enhanced magnetic resonance imaging, was defined as a > 40% decline in K^trans after 2 weeks of treatment. The percentage of peripheral blood lymphocyte subsets were also analysed.

RESULTS

Fifty-five patients were enrolled. The response rate was 13%, and the disease-control rate was 53%. The 6 month progression-free survival rate was 9.1%. The median progression-free and overall survival was 1.8 months and 8.9 months respectively. Early α-fetoprotein response was significantly associated with higher disease-control rate (76% vs 22%, P = .001) and longer progression-free survival (P = .020). Vascular response was not associated with any treatment outcomes. Patients with a high pre-treatment B cell percentage were more likely to have disease control (70% vs 36%, P = .010) and exhibited longer progression-free survival (P < .001) and overall survival (P = .042).

CONCLUSIONS

Lenalidomide exhibited moderate activity as second-line therapy for advanced HCC. Its immunomodulatory effects should be further explored (www.clinicaltrials.gov NCT01545804).

Immunotherapeutic approaches for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a cancer with a high mortality rate due to the fact that the diagnosis usually occurs at anadvanced stage. Even in case of curative surgical treatment, recurrence is common. Sorafenib and regorafenib are the only therapeutic agents that have been demonstrated to be effective in advanced HCC, thus novel curative approaches are urgently needed. Recent studies focus on the role of immune system in HCC. In fact, the unique immune response in the liver favors tolerance, which can represent a real challenge for conventional immunotherapy in these patients. Spontaneous immune responses against tumor antigens have been detected, and new immune therapies are under investigation: dendritic cell vaccination, immune-modulator strategy, and immune checkpoint inhibition. In recent years different clinical trials examining the use of immunotherapy to treat HCC have been conducted with initial promising results. This review article will summarize the literature data concerning the potential immunotherapeutic approaches in HCC patients.

Phase I Study of Lenalidomide and Sorafenib in Patients With Advanced Hepatocellular Carcinoma

LESSONS LEARNED

Combination therapies in patients with hepatocellular carcinoma can be associated with overlapping toxicity and are therefore poorly tolerated.Using sorafenib at the maximum tolerated dose can lead to a higher incidence of toxicities. Consequently, combination studies might evaluate sorafenib at alternative schedules or doses to improve tolerance, recognizing this could affect sorafenib efficacy.Although this combination was poorly tolerated, it does not exclude further evaluation of new-generation immunomodulator drugs or immune checkpoint inhibitors in the hope of optimizing tolerance and safety.

BACKGROUND

Sorafenib is the standard treatment for advanced hepatocellular carcinoma (HCC), and to date, no combination therapy has demonstrated superior survival compared with sorafenib alone. The immunosuppressive microenvironment in HCC is a negative predictor for survival. Lenalidomide is an immunomodulator and antiangiogenic agent, with limited single-agent efficacy in HCC. Based on these data, we designed a phase I study of sorafenib plus lenalidomide to determine the safety and preliminary antitumor activity of this combination.

METHODS

This was an open-label, phase I study with a 3+3 dose escalation/de-escalation design. The starting dose of sorafenib was 400 mg p.o. b.i.d. and of lenalidomide was 15 mg p.o. daily with a planned dose escalation by 5 mg per cohort up to 25 mg daily. Dose de-escalation was planned to a sorafenib dose of 400 mg p.o. daily combined with two doses of lenalidomide: 10 mg p.o. daily for a 28-day cycle (cohort 1) and 10 mg p.o. daily for a 21- or 28-day cycle (cohort 2). Patients with cirrhosis, a Child-Pugh score of A-B7, and no previous systemic therapy were eligible.

RESULTS

Five patients were enrolled. Their median age was 56 years (range 39-61), and the ECOG status was 0-2. Four patients were treated at dose level (DL) 1. Because of the poor tolerance to the combination associated with grade 2 toxicities, one more patient was treated at DL -1. No dose-limiting toxicity was observed as specified per protocol. The most common toxicities were nausea, anorexia, pruritus, elevated liver enzymes, and elevated bilirubin. Three patients experienced one or more of the following grade 3 toxicities: fatigue (DL 1), increased bilirubin (DL 1), skin desquamation (DL -1), and elevated transaminase levels (DL 1). The median duration of therapy was 1 cycle (range 1-3). All patients discontinued the study, 4 because of progressive disease and 1 by patient preference. The best confirmed response was progressive disease. The median progression-free survival was 1.0 month (95% confidence interval 0.9-2.8), and the median overall survival was 5.9 months (95% confidence interval 3.68-23.4).

CONCLUSION

In our small study, the combination of lenalidomide and sorafenib was poorly tolerated and showed no clinical activity. Although the study was closed early because of toxicity concerns, future studies assessing combinations of sorafenib with new-generation immunomodulator drugs or other immunomodulatory agents, should consider lower starting doses of sorafenib to avoid excessive toxicity.

Cabozantinib is selectively cytotoxic in acute myeloid leukemia cells with FLT3-internal tandem duplication (FLT3-ITD)

Cabozantinib is an oral multikinase inhibitor that exhibits anti-tumor activity in several cancers. We found that cabozantinib was significantly cytotoxic to MV4-11 and Molm-13 cells that harbored FLT3-ITD, resulting in IC50 values of 2.4 nM and 2.0 nM, respectively. However, K562, OCI-AML3 and THP-1 (leukemia cell lines lacking FLT3-ITD) were resistant to cabozantinib, showing IC50 values in the micromolar range. Cabozantinib arrested MV4-11 cell growth at the G0/G1 phase within 24 h, which was associated with decreased phosphorylation of FLT3, STAT5, AKT and ERK. Additionally, cabozantinib induced MV4-11 cell apoptosis in a dose-dependent manner (as indicated by annexin V staining and high levels of cleaved caspase 3 and PARP-1), down-regulated the anti-apoptotic protein survivin and up-regulated the pro-apoptotic protein Bak. Thus, cabozantinib is selectively cytotoxic to leukemia cells with FLT3-ITD, causing cell-cycle arrest and apoptosis. In mouse xenograft model, cabozantinib significantly inhibited MV4-11 and Molm-13 tumor growth at a dosage of 10 mg/kg and showed longer survival rate. Clinical trials evaluating the efficacy of cabozantinib in acute myeloid leukemia (AML) with FLT3-ITD are warranted.