Cell Culture System for Analysis of Genetic Heterogeneity Within Hepatocellular Carcinomas and Response to Pharmacologic Agents.

BACKGROUND & AIMS: No targeted therapies have been found to be effective against hepatocellular carcinoma (HCC), possibly due to the large degree of intratumor heterogeneity. We performed genetic analyses of different regions of HCCs to evaluate levels of intratumor heterogeneity and associate alterations with responses to different pharmacologic agents. METHODS: We obtained samples of HCCs (associated with hepatitis B virus infection) from 10 patients undergoing curative resection, before adjuvant therapy, at hospitals in China. We collected 4-9 spatially distinct samples from each tumor (55 regions total), performed histologic analyses, isolated cancer cells, and carried them low-passage culture. We performed whole-exome sequencing, copy-number analysis, and high-throughput screening of the cultured primary cancer cells. We tested responses of an additional 105 liver cancer cell lines to a fibroblast growth factor receptor (FGFR) 4 inhibitor. RESULTS: We identified a total of 3670 non-silent mutations (3192 missense, 94 splice-site variants, and 222 insertions or deletions) in the tumor samples. We observed considerable intratumor heterogeneity and branched evolution in all 10 tumors; the mean percentage of heterogeneous mutations in each tumor was 39.7% (range, 12.9%-68.5%). We found significant mutation shifts toward C>T and C>G substitutions in branches of phylogenetic trees among samples from each tumor (P < .0001). Of note, 14 of the 26 oncogenic alterations (53.8%) varied among subclones that mapped to different branches. Genetic alterations that can be targeted by existing pharmacologic agents (such as those in FGF19, DDR2, PDGFRA, and TOP1) were identified in intratumor subregions from 4 HCCs and were associated with sensitivity to these agents. However, cells from the remaining subregions, which did not have these alterations, were not sensitive to these drugs. High-throughput screening identified pharmacologic agents to which these cells were sensitive, however. Overexpression of FGF19 correlated with sensitivity of cells to an inhibitor of FGFR 4; this observation was validated in 105 liver cancer cell lines (P = .0024). CONCLUSIONS: By analyzing genetic alterations in different tumor regions of 10 HCCs, we observed extensive intratumor heterogeneity. Our patient-derived cell line-based model, integrating genetic and pharmacologic data from multiregional cancer samples, provides a platform to elucidate how intratumor heterogeneity affects sensitivity to different therapeutic agents.

Nailfold capillary measurements correlated to NOTCH3 R544C mutation in preclinical CADASIL patients.

BACKGROUND: Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a hereditary disease caused by NOTCH3 mutation. Nailfold capillaroscopy is a non-invasive technique typically used for rheumatic diseases. It has potential in other conditions linked to vascular pathology. However, capillaroscopy in CADASIL has not been explored. This study aims to investigate whether capillaroscopy measurements can correlate with brain vascular changes in preclinical CADASIL patients, specifically those with NOTCH3 mutation. METHODS: This study included 69 participants from the Taiwan Precision Medicine Initiative (TPMI) dataset who visited Taichung Veterans General Hospital from January to December 2022. All individuals underwent genetic studies, brain imaging and nailfold capillaroscopy. The Mann-Whitney U test was used to compare results of brain imaging between carriers and controls. It was also used to compare measurements in nailfold capillaroscopy within each group. Spearman Rank Correlation Analysis was used to explore the relationship between capillary measurements and brain MRI results. RESULTS: White matter hyperintensities (WMH) expression was positively correlated with capillary dimension and negatively correlated with density. Our results presented that R544C carriers exhibited a diffuse increase in WMH (p < 0.001) and a global reduction in gray matter volume but preserved in specific areas. The white matter lesion scores in all brain regions were higher in the mutation carriers than the controls. (p < 0.001). CONCLUSION: This research highlights the association of nailfold capillaroscopy findings with white matter lesions in preclinical CADASIL patients. Capillaroscopy guides an effective screening strategy in individuals with NOTCH3 mutations.

A novel mouse model of contralateral C7 transfer via the pretracheal route: A feasibility study.

BACKGROUND: Contralateral seventh cervical nerve transfer (contralateral C7 transfer) is a novel treatment for patients with spastic paralysis, including stroke and traumatic brain injury. However, little is known on changes in plasticity that occur in the intact hemisphere after C7 transfer. An appropriate surgical model is required. NEW METHOD: We described in detail the anatomy of the C7 in a mouse model. We designed a pretracheal route by excising the contralateral C6 lamina ventralis, and the largest nerve defect necessary for direct neurorrhaphy was compared with defect lengths in a prespinal route. To test feasibility, we performed in-vivo surgery and assessed nerve regeneration by immunofluorescence, histology, electrophysiology, and behavioral examinations. RESULTS: Two types of branching were found in the anterior and posterior divisions of C7, both of which were significantly larger than the sural nerve. The length of the nerve defect was drastically reduced after contralateral C6 lamina ventralis excision. Direct tension-free neurorrhaphy was achieved in 66.7% of mice. The expression of neurofilament in the distal segment of the regenerated C7 increased. Histological examination revealed remyelination. Behavioral tests and electrophysiology tests showed functional recovery in a traumatic brain injury mouse. COMPARISON WITH EXISTING METHODS: This is the first direct tension-free neurorrhaphy mouse model of contralateral C7 transfer which shortened the time of nerve regeneration; previous models have used nerve grafting. CONCLUSIONS: This paper describes a simple, reproducible, and effective mouse model of contralateral C7 transfer for studying brain plasticity and exploring potential new therapies after unilateral cerebral injury.

Antitumor immunity by a dendritic cell vaccine encoding secondary lymphoid chemokine and tumor lysate on murine prostate cancer.

AIM: To investigate the antitumor immunity by a dendritic cell (DC) vaccine encoding secondary lymphoid chemokine gene and tumor lysate on murine prostate cancer. METHODS: DC from bone marrow of C57BL/6 were transfected with a plasmid vector expressing secondary lymphoid chemokine (SLC) cDNA by Lipofectamine 2,000 liposome and tumor lysate. Total RNA extracted from SLC+lysate-DC was used to verify the expression of SLC by reverse transcriptase-polymerase chain reaction (RT-PCR). The immunotherapeutic effect of DC vaccine on murine prostate cancer was assessed. RESULTS: We found that in the prostate tumor model of C57BL/6 mice, the administration of SLC+lysate-DC inhibited tumor growth most significantly when compared with SLC-DC, lysate-DC, DC or phosphate buffer solution (PBS) counterparts (P < 0.01). Immunohistochemical fluorescent staining analysis showed the infiltration of more CD4(+), CD8(+) T cell and CD11c(+) DC within established tumor treated by SLC+lysate-DC vaccine than other DC vaccines (P < 0.01). CONCLUSION: DC vaccine encoding secondary lymphoid chemokine and tumor lysate can elicit significant antitumor immunity by infiltration of CD4(+), CD8(+) T cell and DC, which might provide a potential immunotherapy method for prostate cancer.

More than chemotaxis: a new anti-tumor DC vaccine modified by rAAV2-SLC.

Secondary lymphoid tissue chemokine (SLC) is strongly expressed in secondary lymphoid organs. Its ability to facilitate chemotaxis of both dendritic cells (DC) and T cells makes it a promising candidate for cancer therapy. In this study, we modified a BMDC vaccine by incorporating the SLC mature peptide gene. The efficacy of this vaccine was evaluated using a mouse hepatocellular carcinoma (HCC) model, with rAAV2 as the gene delivery vector. The rAAV2 encoding SLC (rAAV2-SLC) transfected immature BMDCs at high efficiency and the anti-tumor effects of SLC gene modified BMDCs (rAAV2-SLC/BMDC) were evaluated. In addition, rAAV2-SLC/BMDC vaccine injected directly into tumors attracted more CD4(+) and CD8(+) T lymphocytes into tumors and showed stronger anti-tumor effects than footpad delivery. Moreover, we found that the phenotypic expression of MHC II, the secretion of IL-12 and IFN-gamma, and T cell stimulation were increased in vitro following treatment with rAAV2-SLC/BMDC vaccine and these responses were inhibited by PTX. In vivo, PTX also inhibited the anti-tumor effects of the vaccine. The results suggest that the expression of SLC by rAAV2-SLC/BMDC plays more than a chemotactic role in anti-tumor responses, thus these studies further demonstrate that SLC has potential to be valuable in cancer therapy.

[Functional localization of metastasis suppressor genes for HCC on human chromosome 8].

OBJECTIVE: We previously showed that introduction of a normal, neomycin-tagged human chromosome 8 reduced the metastatic capacity of C5F rat liver cancer cell line, which had high metastatic potential without affecting tumorigenicity, suggesting the presence of one or more metastasis suppressor genes encoded on human chromosome 8. We proceeded to define further the region harboring the metastasis suppressor gene(s) and to determine the random loss of human chromosome 8 by PCR amplification of sequence tag site (STS) markers. METHODS: The national Center for Biotechnology Information (NCBI) databases were used as references of the relative genetic distances of the STS markers. C5F genomic DNA and A9/neo8 genomic DNA were used as negative and positive controls for chromosome 8 amplification, respectively. Genomic DNA was isolated and quantified from cultured hybrid clones (A9/C5F-1 and A9/C5F-2 microcell hybrid clones served as metastasis-unsuppressed groups; A9/C5F-4, A9/C5F-8 and A9/C5F-10 microcell hybrid clones served as metastasis suppressed groups). STS-PCR products were separated by electrophoresis through 2% agarose gel. RESULTS: Metastasis-suppressed microcell hybrid clones (A9/C5F-4, A9/C5F-8 and A9/C5F-10) conserved STS markers between D8S542 --> D8S1973 (8p21.1-23.1). In contrast, metastasis-unsuppressed clones (A9/C5F-1 and A9/C5F-2) lacked several markers in this region. In attempts to refine the region retained in the microcell suppressed clones, more densely spaced STS markers in the human chromosome 8p21.1-23.1 were used. We found that the metastasis-suppressed clones retained 18cM region between D8S542 and D8S1973 (8P21.1-23.1), where as the metastasis-unsuppressed clones lacked the region. CONCLUSION: Our results suggest that a metastasis suppressor gene is located within the interval between D8S542 and D8S1973 on human chromosome 8p21.1-23.1.

[A preliminary study of the killing function in vitro by T lymphocytes activated by dendritic cells loaded with exosomes secreted by hepatic cancer cell lines with high or low metastatic potentials].

OBJECTIVE: To study the tumor cell killing function of T lymphocytes stimulated by dendritic cells (DC) and to analyze the differences of protein contents of exosomes in each type of cell. METHODS: The exosomes of hepatic cell lines with high (P group) or low (F group) metastatic potentials were isolated by a process of four-step centrifugation and the collected exosomes were observed under an electron microscope (EM). The tumor cell killing experiment was performed by adding T lymphocytes activated by DC loaded with exosomes from corresponding P and F group cells and was studied using 3H-TdR experiments. The proteomic analysis was performed by surface-enhanced laser desorption/ ionization time of flight mass spectrometry (SELDI-TOF-MS ) on the exosomes of P and F group cells. RESULTS: The density distribution and content of exosomes in the P group were not equal to those in the F group observed by EM. The CD80, CD86, MHC-I and MHC-II in the P group were 64.27+5.00, 44.89+10.11, 84.35+19.89 and 59.03+19.37, and those in the F group were 71.53+4.85, 50.01+9.50, 80.68+29.87 and 58.86+21.11, respectively (P>0.05, compared with the control group). The counts per minute value in the P group was 528.40+179.06 and 78.80+24.44 in the F group after being loaded with exosomes (P<0.01, compared with the control group). There were significant differences between the proteins in the exosomes of hepatic cancer cell lines with high or low metastatic potentials. CONCLUSION: Exosomes have potential values of application in immunotherapy and in biotherapy for recurrences and metastases of hepatic carcinomas.

[The relationship between lymphangiogenesis and lymphatic metastasis in murine hepatic carcinoma of high and low metastatic potentialities].

OBJECTIVES: To study the relationship between lymphangiogenesis and lymphatic metastasis in mice bearing hepatic carcinoma and analyze the mechanism of the lymphatic metastasis. METHODS: Hepatic carcinoma cell lines of high and low potentialities of lymphatic metastasis were injected into the footpads of Balb/c mice. Their metastases to lymph nodes were examined. The tumor tissues of each group were stained with 5'-nucleotidase-ALP to observe the lymphoangiogenesis. The total RNA of high and low metastatic potential cell lines were extracted for metastasis gene DNA array. The vascular endothelial cell growth factor C (VEGF-C) and VEGF-D of each cell line were detected using semi-quantitative RT-PCR and were further quantatively analyzed using real time PCR. RESULTS: The para-common iliac a. and renal hilar lymph nodes metastases of the high metastatic potential cells were significantly higher than in the controls (P>0.05). The quantity of lymphatic vessels in the high metastasis group was significantly larger than that of the control group (P<0.05). The expressions of CD44, E-cadherin, HER2/neu, H-Ras and VEGF-C in the high metastasis group were higher than those in the low metastasis group shown by the cDNA micro array experiment but the expressions of nm23A, nm23-E4, p16ink4a, CD61 were lower. The VEGF-C expression was higher and the VEGF-D was lower in the high metastasis group compared to those of the low metastasis group shown by semi-quantitative RT-PCR. The secretion of VEGF-D was significantly lower and the ratio of VEGF-C/VEGF-D was significantly higher in the high metastasis group than the low metastasis group (P<0.05). CONCLUSIONS: The lymphatic metastasis of hepatic carcinoma is related to lymphoangiogenesis. The changes of VEGF-C and VEGF-D expressions might be a cause influencing the lymphoangiogenesis. VEGF-C/VEGF-D might be an effective parameter in affecting lymphatic metastases.

Inflammatory microenvironment contributes to epithelial-mesenchymal transition in gastric cancer.

Gastric cancer (GC) is the fifth most common malignancy in the world. The major cause of GC is chronic infection with Helicobacter pylori (H. pylori). Infection with H. pylori leads to an active inflammatory microenvironment that is maintained by immune cells such as T cells, macrophages, natural killer cells, among other cells. Immune cell dysfunction allows the initiation and accumulation of mutations in GC cells, inducing aberrant proliferation and protection from apoptosis. Meanwhile, immune cells can secrete certain signals, including cytokines, and chemokines, to alter intracellular signaling pathways in GC cells. Thus, GC cells obtain the ability to metastasize to lymph nodes by undergoing the epithelial-mesenchymal transition (EMT), whereby epithelial cells lose their epithelial attributes and acquire a mesenchymal cell phenotype. Metastasis is a leading cause of death for GC patients, and the involved mechanisms are still under investigation. In this review, we summarize the current research on how the inflammatory environment affects GC initiation and metastasis via EMT.

[Relationship between DLC-1 expressions and metastasis in hepatocellular carcinoma].

OBJECTIVES: To study the relationship between the expression level of DLC-1 mRNA (located in 8p) and the invasion/metastasis of human hepatocellular carcinoma (HCC). METHODS: Fifty-one surgical specimens of human HCC were divided into high-invasive and low invasive groups according to their clinicopathological features. DLC-1 mRNA expression was studied in the 51 HCC specimens as well as 5 different metastasis potential cell lines using real-time quantitative PCR (RQ-PCR). RESULTS: The expression level of DLC-1 mRNA in HCC specimens with high invasiveness was significantly lower than that with low invasiveness (P < 0.05). The expression levels of DLC-1 mRNA were significantly different between non-metastatic (Hep3B and HepG2) and metastatic (MHCC97-H, MHCC97-L and HCCLM3) cell lines (P < 0.05). From MHCC97-L to HCCLM3, with an increase of invasiveness and metastatic potentials, the expression level of DLC-1 decreased correspondingly, and its expression level in HCCLM3 was significantly lower than that in MHCC97-L (P < 0.01). CONCLUSION: The expression of DLC-1 mRNA may play an important role in inhibiting the invasiveness and metastasis of HCC.

[Influence of reconstruction of immunological functions of T lymphocytes on mouse hepatocarcinoma metastasis].

OBJECTIVE: To investigate the effectiveness of reconstruction of immunological functions of T cells on the degree of metastases of mouse hepatocarcinoma and the mechanisms of their functioning. METHODS: The T cell model of immunological functions in Balb/c nu/nu mice was established and the effectiveness of the model was evaluated. The mice were divided into 4 groups. The immunological functions of T cells in experiment groups of Balb/c nu/nu mice were reconstructed. Metastases of the cancer in lymph nodes in each group were examined histologically. The formation time and growth rate of the tumors were calculated. The expression of MHCI and II of the tumor cell line and the difference of expression of immune associated gene were detected by Th1-Th2-Th3 gene array. RESULTS: The ratio of CD3, CD4, CD8 and CD4/CD8 in the reconstructed group was higher than that in the control group. The average formation time was 7.7+/-0.6 days in Balb/c nu/nu mice and 11.5+/-1.3 days in Balb/c mice. The extent of metastases of the experiment group was lower than that of the control group (P < 0.05). The expression of MHCI of the high metastasis cell line was lower than that of the low metastasis cell line (P < 0.05). The expressions of Th1/Th2 associated genes in lymphocytes of high metastasis mice were lower than those of the low metastasis mice. CONCLUSION: Reconstruction of the immunological function of T cells can influence the metastasis of mouse hepatocarcinoma. The alteration of MHC molecule and low expression of Th1/Th2 correlated genes in lymphocytes may be a factor influencing the metastasis of liver cancer.

Chemokines and their receptors play important roles in the development of hepatocellular carcinoma.

The chemokine system consists of four different subclasses with over 50 chemokines and 19 receptors. Their functions in the immune system have been well elucidated and research during the last decades unveils their new roles in hepatocellular carcinoma (HCC). The chemokines and their receptors in the microenvironment influence the development of HCC by several aspects including: inflammation, effects on immune cells, angiogenesis, and direct effects on HCC cells. Regarding these aspects, pre-clinical research by targeting the chemokine system has yielded promising data, and these findings bring us new clues in the chemokine-based therapies for HCC.

[Effects of hepatectomized rat serum on the transdifferentiation of adult rat bone marrow cells into hepatocyte-like cells].

OBJECTIVES: To study the effects of hepatectomized rat serum and hepatocyte growth factor (HGF) on the transdifferentiation of adult rat bone marrow stem cells (ABMSCs) into hepatic parenchymal cells. METHODS: The serum was collected from the rats 24 hours after being subjected to subtotal hepatectomy. ABMSCs were collected and cultured in DMEM/F12 (1:1) containing the hepaetectomized rat serum or HGF. The differentiated hepatocyte-like cells were labeled with CM-DiI and administrated by tail vein injection into the isogeneic rats. The cultured and injected cells were both identified by immunocytochemistry and cultured cells were assayed using RT-PCR and Western blot. RESULTS: Hepatectomized rat serum and HGF were demonstrated to have the effect of inducing transdifferentiation of ABMSCs into hepatocyte-like cells in vitro. The differentiated cells expressed albumin mRNA and albumin after 7 days++'s co-incubation. Albumin-expressing and CM-DiI positive hepatocyte-like cells were characterized in livers and spleens of the rats injected with the cultivated cells. CONCLUSION: ABMSCs could transdifferentiate into hepatic parenchymal cells by hepatectomized rat serum or HGF.

Detection of Aß plaques by a novel specific MRI probe precursor CR-BSA-(Gd-DTPA)n in APP/PS1 transgenic mice.

Amyloid plaques are one of the hallmarks of Alzheimer's disease (AD). The lack of specific probes that can detect individual senile plaques in AD has prompted the development of magnetic resonance imaging (MRI) probes. In this study, based on DTPA-gadolinium (III) and congo red (CR), a novel specific MRI probe precursor CR-BSA-(Gd-DTPA)n was successfully synthesized. Its ability to bind to amyloid plaques was evaluated by brain sections from APP/PS1 transgenic mice. Its specificity for Aß plaques was further demonstrated by immunohistochemistry (IHC) staining with the monoclonal antibody to the Aß protein. Meanwhile, the amyloid deposits detected by the CR-BSA-(Gd-DTPA)n were matched to the amyloid deposits detected by Aß specific antibody. We also found that a few amyloid-like deposits which was not detected by IHC. The findings indicated that the probe perhaps could detect the neurofibrillary tangles (NFT) similar to the effect of CR itself, and this will be verified in future experiments. The works suggested that the Aß protein-specific magnetic resonance contrast agent precursor CR-BSA-(Gd-DTPA)n can be used as a potential fluorescence and MR multi-modal imaging probe precursor to display individual senile plaques in AD.

Local expression of secondary lymphoid tissue chemokine delivered by adeno-associated virus within the tumor bed stimulates strong anti-liver tumor immunity.

Development of an effective antitumor immune response depends on the appropriate interaction of effector and target cells. Thus, the expression of chemokines within the tumor may induce a more potent antitumor immune response. Secondary lymphoid tissue chemokine (SLC) is known to play a critical role in establishing a functional microenvironment in secondary lymphoid tissues. Its capacity to attract dendritic cells (DCs) and colocalize them with T cells makes it a good therapeutic candidate against cancer. In this study, we used SLC as a treatment for tumors established from a murine hepatocellular carcinoma model. SLC was encoded by recombinant adeno-associated virus (rAAV), a system chosen for the low host immunity and high efficiency of transduction, enabling long-term expression of the gene of interest. As a result, rAAV-SLC induced a significant delay of tumor progression, which was paralleled by a profound infiltration of DCs and activated CD4(+) T cells and CD8(+) T cells (CD3(+) CD69(+) cells) into the tumor site. In addition, rAAV-SLC treatment was also found to reduce tumor growth in nude mice, most likely due to inhibition of neoangiogenesis. In conclusion, local expression of SLC by rAAV represents a promising approach to induce immune-mediated regression of malignant tumors.