Treatment of hepatocellular carcinoma with adenoviral vector-mediated Flt3 ligand gene therapy

Immunogenicity and effectiveness of an mRNA therapeutic vaccine for HPV-related malignancies

Human papillomavirus (HPV) infections account for several human cancers. There is an urgent need to develop therapeutic vaccines for targeting preexisting high-risk HPV (such as HPV 16 and 18) infections and lesions, which are insensitive to preventative vaccines. In this study, we developed a lipid nanoparticle-formulated mRNA-based HPV therapeutic vaccine (mHTV), mHTV-02, targeting the E6/E7 of HPV16 and HPV-18. mHTV-02 dramatically induced antigen-specific cellular immune response and robust memory T-cell immunity in mice, besides significant CD8+ T-cell infiltration and cytotoxicity in TC-1 tumors expressing HPV E6/E7, resulting in tumor regression and prolonged survival in mice. Moreover, evaluation of routes of administration found that intramuscular or intratumoral injection of mHTV-02 displayed significant therapeutic effects. In contrast, intravenous delivery of the vaccine barely showed any benefit in reducing tumor size or improving animal survival. These data together support mHTV-02 as a candidate therapeutic mRNA vaccine via specific administration routes for treating malignancies caused by HPV16 or HPV18 infections.

Autophagy and ALS: mechanistic insights and therapeutic implications

Mechanisms of protein homeostasis are crucial for overseeing the clearance of misfolded and toxic proteins over the lifetime of an organism, thereby ensuring the health of neurons and other cells of the central nervous system. The highly conserved pathway of autophagy is particularly necessary for preventing and counteracting pathogenic insults that may lead to neurodegeneration. In line with this, mutations in genes that encode essential autophagy factors result in impaired autophagy and lead to neurodegenerative conditions such as amyotrophic lateral sclerosis (ALS). However, the mechanistic details underlying the neuroprotective role of autophagy, neuronal resistance to autophagy induction, and the neuron-specific effects of autophagy-impairing mutations remain incompletely defined. Further, the manner and extent to which non-cell autonomous effects of autophagy dysfunction contribute to ALS pathogenesis are not fully understood. Here, we review the current understanding of the interplay between autophagy and ALS pathogenesis by providing an overview of critical steps in the autophagy pathway, with special focus on pivotal factors impaired by ALS-causing mutations, their physiologic effects on autophagy in disease models, and the cell type-specific mechanisms regulating autophagy in non-neuronal cells which, when impaired, can contribute to neurodegeneration. This review thereby provides a framework not only to guide further investigations of neuronal autophagy but also to refine therapeutic strategies for ALS and related neurodegenerative diseases.Abbreviations: ALS: amyotrophic lateral sclerosis; Atg: autophagy-related; CHMP2B: charged multivesicular body protein 2B; DPR: dipeptide repeat; FTD: frontotemporal dementia; iPSC: induced pluripotent stem cell; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; PINK1: PTEN induced kinase 1; RNP: ribonuclear protein; sALS: sporadic ALS; SPHK1: sphingosine kinase 1; TARDBP/TDP-43: TAR DNA binding protein; TBK1: TANK-binding kinase 1; TFEB: transcription factor EB; ULK: unc-51 like autophagy activating kinase; UPR: unfolded protein response; UPS: ubiquitin-proteasome system; VCP: valosin containing protein.

Immune therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death worldwide. Currently, there are no treatment options available for a large number of these patients. One of the mechanisms that may contribute to tumor growth is the lack of an effective immune response toward viral antigens or other tumor-associated antigens (TAAs). Immunotherapy has been tested as a potential therapeutic option for these patients. Several methods of immune modulation for augmenting antitumor immunity are being explored and have been shown to be effective in suppressing HCC growth in animal models. Activation of HCC-specific response can be accomplished by targeting hepatitis B or C viral antigens, alpha-fetoprotein, or other TAAs. This review summarizes part of the recent data on the use of adoptive transfer of immunity against viral antigens, oral immune modulation against TAAs, and the use of pulsed innate immune cells and gut adjuvants for the suppression of HCC; it reviews some additional new immunotherapeutic approaches.

Inhibitory effects of genistein on metastasis of human hepatocellular carcinoma

AIM: To investigate the inhibitory effects of genistein on metastasis of MHCC97-H hepatocellular carcinoma cells and to explore the underlying mechanism.

METHODS: MHCC97-H hepatocellular carcinoma cells were exposed to genistein. A cell attachment assay was carried out in a microculture well pre-coated with fibronectin. The invasive activity of tumor cells was assayed in a transwell cell culture chamber, and cell cycle and apoptosis were evaluated by a functional assay. In addition, the expression and phosphorylation of FAK were detected by Western blotting. In situ xenograft transplantation of hepatocellular carcinoma was performed in 12 nude mice and lung metastasis of hepatocellular carcinoma was observed.

RESULTS: Genistein significantly inhibited the growth of MHCC97-H cells in vitro. Adhesion and invasiveness of MHCC97-H cells were inhibited in a concentration-dependent fashion, and the inhibitory effect of genistein was more potent in the 10 μg/mL and 20 μg/mL genistein-treated groups. Genistein caused G₀/G₁ cell cycle arrest, an S phase decrease, and increased apoptosis. The expression and phosphorylation of FAK in MHCC-97H cells were significantly decreased. In situ xenograft transplantation of hepatocellular carcinoma was also significantly suppressed by genistein. The number of pulmonary micrometastatic foci in the genistein group was significantly lower compared with the control group (12.3 ± 1.8 vs 16.6 ± 2.6, P < 0.05).

CONCLUSION: Genistein appears to be a promising agent in the inhibition of metastasis of hepatocellular carcinoma.

Eradication of hepatoma and colon cancer in mice with Flt3L gene therapy in combination with 5-FU

We developed a recombinant defective adenovirus with an insert of gene encoding extracellular domain of mouse Flt3L (Ad-mFlt3L) under control of cytomegalovirus promoter to investigate the biological efficacy of Flt3L in combination with chemotherapeutical drug, 5-FU, in eliciting an effective anti-cancer immunity in mouse hepatoma and colon cancer model systems. The constructed Ad-mFlt3L efficiently infected hepatoma and colon cancer cells both in vitro and in vivo, leading to a high production of mFlt3L proteins in association with accumulation of DCs, NK cells and lymphocytes in local tumor tissues. Administration of Ad-mFlt3L can protect bone marrow injury caused by 5-Fu and stimulates proliferation and maturation of lymphocytes, APCs and NKs. Intratumoral injection of Ad-mFlt3L followed by an intraperitoneal administration of 5-Fu significantly inhibited tumor growth and cured established tumors. Adenovirus mediated Flt3L gene therapy synergies with chemotherapeutic drug, 5-Fu, in elicitation of long-lasting antitumor immunity. The tumor specific immunity can be adoptively transferred into naïve animals successfully by transfusion of CD3+CD8+ T cells from the treated mice. The data suggests that adenovirus mediated Flt3L gene therapy in combination with 5-Fu chemotherapy may open a new avenue for development of anti-cancer chemogenetherapy.