Clinical characteristics and outcomes of newly diagnosed patients with human immunodeficiency virus-associated Burkitt lymphoma: the Central and Western China AIDS lymphoma league 002 study (CALL-002 study).

BACKGROUND: Despite the introduction of combined antiretroviral therapy, the clinical outcomes of HIV-associated Burkitt lymphoma (BL) remain poor. METHODS: To evaluate the clinical characteristics, prognostic factors, and outcomes of HIV-associated BL, we conducted a retrospective analysis of patients from multiple centers in China. RESULTS: The study included 41 patients from 8 medical centers. Among the included population, male patients accounted for 87.8%, with 75.6% in advanced stages. Notably, 46.3% of cases involved bone marrow, while 19.5% involved the central nervous system (CNS). The most commonly used chemotherapy regimen was DA-EPOCH ± R, accounting for 53.6% of cases. The overall response rates for patients receiving DA-EPOCH ± R and R-Hyper-CVAD were 59% and 58.2%, respectively. Interestingly, patients receiving regimens containing rituximab had similar complete remission rates (25% vs. 23.5%) and overall survival time (45.69 ± 11.58 vs. 47.79 ± 11.72 months, P = 0.907) compared to those without rituximab, but differed in progression rates (33.3% vs. 47.1%). For the entire cohort, the 1-year progression-free survival (PFS) and overall survival (OS) rates were 52% and 67%, respectively. CNS involvement was independent risk factors for survival, with 1-year PFS and OS rates of 0% and 38% for patients with CNS involvement, and PFS and OS rates of 66% and 75% for patients without CNS involvement. CONCLUSIONS: HIV-associated BL patients in China have poor prognosis and show limited response to current treatment regimens. The absence of CNS involvement significantly improves clinical outcomes. The use of rituximab is not significantly associated with improved outcomes but can reduce disease progression.

Impact of initial chemotherapy cycles and clinical characteristics on outcomes for HIV-associated diffuse large B cell lymphoma patients: The Central and Western China AIDS Lymphoma League 001 study (CALL-001 study).

Introduction: Little is known about the first line induction chemotherapy cycles for HIV-associated diffuse large B-cell lymphoma (DLBCL) as these are less common than HIV-negative lymphoma. Currently, the optimal treatment cycles option remains undefined. Therefore, we performed a multi-center study to analyze the clinical characteristics and outcomes of HIV-associated DLBCL patients in different treatment modes in China. Methods: Totally 273 newly diagnosed HIV-associated DLBCL patients at eleven large academic centers from October 2008 to October 2021, were analyzed. Results: In the entire cohort, the median age was 47 years (range, 21-90) at lymphoma diagnosis, and 223 patients were male (81.7%). One hundred and ninety-four (71.1%) patients were germinal center B-cell-like lymphoma (GCB) subtype. Most patients (65.2%, 178/273) had elevated lactate dehydrogenase (LDH), and advanced Ann Arbor stage (78.9% 213/273) at diagnosis. High international prognostic index (IPI) score (3-5) at diagnosis was found in 65.2% (178/273) of patients. One hundred and fifty-five patients (56.8%) had extranodal involvement. The median CD4 cell count was 168/µl (range, 2-1067), of whom 174 (63.7%) had a CD4 cell count below 200/µl. The median follow-up of our cohort was 10.1 (0.1-160) months. The overall 2-year OS rates 58.0%. Median OS times in the 0, 1-3, 4-6, and >6 cycles chemotherapy cohort were 7.1 months, 20.0 months, not reached, and not reached, respectively (Hazard Ratio (HR)=0.549, 95% Confidence interval (CI) 0.451-0.667; p<0.001). Cox multivariate analysis showed that age ≥60 (HR=2.207, 95%CI 1.321-3.690; p=0.003), high IPI score (3-5) (HR=2.926, 95% CI 1.716-4.988; p<0.001), B symptoms (HR=1.928, 95%CI 1.192-3.119; p=0.007), elevated LDH (HR=1.696, 95%CI 1.031-2.791; p=0.038) and received less than 4 cycles chemotherapy (HR=0.520, 95%CI 0.424-0.637; p<0.001) were independent risk factor for adverse prognosis based on overall survival (OS). Discussion: These results demonstrated that 4-6 cycles chemotherapy were significantly associated with improved outcomes in HIV-associated DLBCL patients. However, >6 cycles chemotherapy did not further improve the survival of patients.

Mitigation of Paeoniae Radix Alba extracts on H2O2-induced oxidative damage in HepG2 cells and hyperglycemia in zebrafish, and identification of phytochemical constituents.

Paeoniae Radix Alba (PRA), as a Traditional Chinese Medicine, is widely used in Chinese cuisine due to high health-benefits and nutrition, but the effect of different polarity of solvents on the extraction of antioxidant and hypoglycemic constituents, as well as the major active compounds remain unclear. In this research, 40, 70, and 95% ethanol were firstly applied to extract the polyphenols from PRA, the extraction yields, total phenolics, and total flavonoids content, free radical scavenging ability, α-glucosidase inhibition ability, and anti-glycation ability of extracts were evaluated spectroscopically. The oxidative damage protection, hypoglycemic activity, and alleviation on peripheral nerve damage were evaluated by H2O2-induced HepG2 cells and hyperglycemic zebrafish models. UPLC-QTOF-MS/MS was used to identify the major chemical constituents. The results showed that 40, 70, and 95% ethanol exhibited insignificant difference on the extraction of phenolics and flavonoids from PRA. All extracts showed promising DPPH⋅ and ABTS⋅+ scavenging ability, α-glucosidase inhibition and anti-glycation ability. In addition, PRA extracts could restore the survival rate of HepG2 cells induced by H2O2, and alleviate the oxidative stress by reducing the content of MDA and increasing the levels of SOD, CAT, and GSH-Px. The 70% ethanol extract could also mitigate the blood glucose level and peripheral motor nerve damage of hyperglycemic zebrafish. Thirty-five compounds were identified from 70% ethanol extract, gallotannins, gallic acid and its derivatives, and paeoniflorin and its derivatives were the dominant bioactive compounds. Above results could provide important information for the value-added application of PRA in functional food and medicinal industry.

Sugemalimab Monotherapy for Patients With Relapsed or Refractory Extranodal Natural Killer/T-Cell Lymphoma (GEMSTONE-201): Results From a Single-Arm, Multicenter, Phase II Study.

PURPOSE: Relapsed or refractory extranodal natural killer/T-cell lymphoma (R/R ENKTL) is a rare and aggressive type of non-Hodgkin lymphoma with limited treatment options. This phase II study evaluated the efficacy and safety of sugemalimab, an anti-PD-L1 monoclonal antibody, in R/R ENKTL. METHODS: Eligible patients received sugemalimab 1,200 mg intravenously once every 3 weeks for up to 24 months or until progression, death, or study withdrawal. The primary end point was objective response rate (ORR) assessed by an independent radiologic review committee. Key secondary end points included ORR assessed by the investigators, complete response rate, duration of response, and safety. RESULTS: At the data cutoff (February 23, 2022), 80 patients were enrolled and followed for a median of 18.7 months. At baseline, 54 (67.5%) had stage IV disease and 39 (48.8%) had received ≥2 lines of prior systemic therapy. Independent radiologic review committee-assessed ORR was 44.9% (95% CI, 33.6 to 56.6); 28 (35.9%) patients achieved a complete response and seven (9.0%) achieved a partial response, with a 12-month duration of response rate of 82.5% (95% CI, 62.0 to 92.6). Investigator-assessed ORR was 45.6% (95% CI, 34.3 to 57.2), and 24 (30.4%) patients achieved a complete response. Most treatment-emergent adverse events were grade 1-2 in severity, and grade ≥ 3 events were reported in 32 (40.0%) patients. CONCLUSION: Sugemalimab showed robust and durable antitumor activity in R/R ENKTL. Treatment was well tolerated with expected safety profile for this drug class.

G protein-biased GPR3 signaling ameliorates amyloid pathology in a preclinical Alzheimer's disease mouse model.

Biased G protein-coupled receptor (GPCR) ligands, which preferentially activate G protein or ß-arrestin signaling pathways, are leading to the development of drugs with superior efficacy and reduced side effects in heart disease, pain management, and neuropsychiatric disorders. Although GPCRs are implicated in the pathophysiology of Alzheimer's disease (AD), biased GPCR signaling is a largely unexplored area of investigation in AD. Our previous work demonstrated that GPR3-mediated ß-arrestin signaling modulates amyloid-ß (Aß) generation in vitro and that Gpr3 deficiency ameliorates Aß pathology in vivo. However, Gpr3-deficient mice display several adverse phenotypes, including elevated anxiety-like behavior, reduced fertility, and memory impairment, which are potentially associated with impaired G protein signaling. Here, we generated a G protein-biased GPR3 mouse model to investigate the physiological and pathophysiological consequences of selective elimination of GPR3-mediated ß-arrestin signaling in vivo. In contrast to Gpr3-deficient mice, G protein-biased GPR3 mice do not display elevated anxiety levels, reduced fertility, or cognitive impairment. We further determined that G protein-biased signaling reduces soluble Aß levels and leads to a decrease in the area and compaction of amyloid plaques in the preclinical AppNL-G-F AD mouse model. The changes in amyloid pathology are accompanied by robust microglial and astrocytic hypertrophy, which suggest a protective glial response that may limit amyloid plaque development in G protein-biased GPR3 AD mice. Collectively, these studies indicate that GPR3-mediated G protein and ß-arrestin signaling produce discrete and separable effects and provide proof of concept for the development of safer GPCR-targeting therapeutics with more directed pharmacological action for AD.

Comparison of efficacy and safety of ripertamab (SCT400) versus rituximab (Mabthera® ) in combination with CHOP in patients with previously untreated CD20-positive diffuse large B-cell lymphoma: A randomized, single-blind, phase III clinical trial.

This study compared the efficacy, safety and immunogenicity of ripertamab (SCT400) and rituximab (Mabthera® ) combined with CHOP as the first-line treatment for Chinese patients with CD20-positive diffuse large B cell lymphoma (DLBCL). This is a randomized, patient-blind, multicenter, active-control, non-inferiority study with parallel design. Patients were randomly (2:1) to receive ripertamab combined with CHOP (S-CHOP) or rituximab (Mabthera® ) combined with CHOP (R-CHOP) for up to 6 cycles. The primary endpoint was the Independent Review Committee (IRC) assessed objective response rate (ORR) in full analysis set (FAS) and the per protocol set (PPS). A total of 364 patients (243 in the S-CHOP and 121 in the R-CHOP groups) were enrolled in this study. In FAS, IRC-assessed ORRs were 93.8% (95% confidence interval (CI) 90.0%, 96.5%) and 94.2% (95% CI: 88.4%, 97.6%) in the S-CHOP and R-CHOP groups (p = 0.9633), respectively. The ORR difference between the two groups -0.4% (95% CI: -5.5%, 4.8%) met the pre-specified non-inferiority margin of -12%. There were no significant differences between the S-CHOP and R-CHOP groups in 1-year progression-free survival rates (81.1% vs. 83.2%, p = 0.8283), 1 year event-free survival rates (56.2% vs. 58.1%, p = 0.8005), and 3-year overall survival rates (81.0% vs. 82.8%, p = 0.7183). The results in PPS were consistent with those in FAS. The rates of treatment-emergent adverse events (TEAEs) and ≥ grade 3 TEAEs were 97.9% and 99.2%, 85.2% and 86.0% in the S-CHOP and R-CHOP groups, respectively in safety set. The percentage of anti-drug antibodies positive patients in the S-CHOP group was numerically lower than the R-CHOP group (10.9% vs. 16.0%). This study demonstrated that S-CHOP was not inferior to R-CHOP in the first-line treatment of Chinese patients with CD20-positive DLBCL in efficacy, safety and immunogenecity. S-CHOP could be an alternative first-line standard treatment regimen for this patient population.

Biogenic iron sulfide functioning as electron-mediating interface to accelerate dissimilatory ferrihydrite reduction by Shewanella oneidensis MR-1.

Microbially driven iron and sulfur geochemical cycles co-exist ubiquitously in subsurface environments and are of environmental relevance. Shewanella species (dissimilatory metal-reducing bacteria) are capable of reducing Fe(III)-(oxyhydr)oxide minerals and diverse sulfur sources using corresponding metabolic pathways and producing FeS secondary minerals. In spite of the ability in promoting bacterial extracellular electron transfer (EET), the specific role of FeS in mediating EET between microbe/mineral interface is still unclear. In this work, the electron-mediating function of biogenic FeS on promoting the reduction of ferrihydrite by S. oneidensis MR-1 using thiosulfate as sulfur source was investigated in terms of Fe(III) reduction percentage, X-ray diffraction and scanning electron microscopy. The results showed that the microbial ferrihydrite reduction was pH-dependent and positively correlated with the addition of thiosulfate. In the presence of thiosulfate, biogenic FeS in nano-scale were formed and deposited on the surfaces of S. oneidensis MR-1 and ferrihydrite to build an interfacial electron transfer bridge between them. The addition of either thiosulfate and in-vitro FeS could rescue the entirely inactivated ability of the mutant (△omcA/mtrC) in ferrihydrite reduction to some extent, but which was obviously inferior to the wild-type strain. Meanwhile, the effect of the biogenic FeS in-situ coating on the surfaces of S. oneidensis MR-1 cells on promoting microbial ferrihydrite reduction was significantly superior to the in-vitro ones. Thus, the in-situ formed biogenic FeS secondary minerals were demonstrated to mediate and accelerate interfacial electron transfer from S. oneidensis MR-1 cells to ferrihydrite through interfacing with the bacterial EET routes, especially Mtr pathway. This work provides an insight into the secondary minerals-mediating interfacial electron transfer between microbes and minerals in the presence of biological S (-II), which has important biogeochemical and environmental implications.

Study of L-Asparaginase, Vincristine, and Dexamethasone Combined With Intensity-modulated Radiation Therapy in Early-Stage Nasal NK/T-Cell Lymphoma.

OBJECTIVES: Natural killer/T-cell lymphoma (NKTCL) is aggressive, and carries a poor prognosis worldwide. This retrospective study aimed to evaluate the clinical efficacy and safety of the LVD regimen (L-asparaginase, vincristine, and dexamethasone) combined with intensity-modulated radiation therapy (IMRT) for the treatment of early-stage nasal NKTCL in a Chinese population. METHODS: The clinical data were collected from patients treated between March 2010 and January 2017. Patients received LVD chemotherapy combined with IMRT, and were followed for 30 to 90 months. All received radiotherapy at the end of the first/second cycle of chemotherapy. The survival curves were generated by the Kaplan-Meier method. RESULTS: Among 94 patients who received 2 to 6 cycles (mean, 4 cycles) of treatments, 56 and 25 achieved complete and partial remission, respectively; 2 and 11 experienced stable disease and progressive disease. The overall objective response was 86.2%. Patients with elevated lactate dehydrogenase and skin invasion had a lower objective response rate. The progression-free survival rates at 1, 3, and 5 years were 90.3%, 73.5%, and 71.3%; the corresponding overall survival rates were 91.4%, 74.3%, and 74.3%. The main adverse events were myelosuppression (63.8% grades I to II, 12.8% grade III), gastrointestinal symptoms (63.8% grades I to II), hepatic lesion (55.3% grades I to II), hypoproteinemia (46.8% grades I to II), skin allergies (77.7% grades I to II, 3.2% grade III), and oral mucosal lesions (44.7% grades I to II, 33% grade III). No severe pancreatitis, anaphylaxis, or toxicity-related death was observed. CONCLUSION: In patients with early-stage nasal NKTCL, our LVD-IMRT regimen produced excellent, durable therapeutic benefit in most patients, with acceptable toxicity and no acute mortality.

Gender Disparity in the Relationship between Prevalence of Thyroid Nodules and Metabolic Syndrome Components: The SHDC-CDPC Community-Based Study.

The study is aimed to investigate the pathogenesis underlying the increased prevalence of thyroid nodule (TN) in different levels of metabolic syndrome (MetS) components and analyze the relationships between TN and MetS components. A total of 6,798 subjects, including 2201 patients with TN, were enrolled in this study. Anthropometric, biochemical, thyroid ultrasonographic, and other metabolic parameters were all measured. There was obviously sexual difference in the prevalence of TN (males 26.0%, females 38.5%, resp.). The prevalence of TN in hyperuricemia (45.7% versus 37.4%, P = 0.001), NAFLD (41.2% versus 36.4%, P < 0.05), and MetS (41.4% versus 35.4%, P < 0.001) groups was significantly increased only in females. Insulin resistance [OR = 1.31 (1.15, 1.49)], MetS [OR = 1.18 (1.03, 1.35)], and diabetes [OR = 1.25 (1.06, 1.48)] were all independent risk factors for TN in total subjects, whereas, after stratified analysis of gender, MetS [OR = 1.29, (1.09, 1.53)] and diabetes [OR = 1.47, (1.17, 1.84)] are still strongly and independently associated with the higher risks of TN in female subjects, but not in males. Our results suggest that the components of MetS might associate with the higher risks of TN in women than in men, but further cohort study of this gender disparity in the association between TN and MetS is required.

[Toxoplasma gondi Antibody Profile in Patients with Leukemia or Lymphoma].

Blood samples were collected from patients with leukemia (n = 150) or lymphoma (n = 150) in the Cancer Hospital from March to September 2014. The specific antibodies (IgG, IgM) to, and circulating antigens (CAg) of Toxoplasma gondii were determined by ELISA. A 529 bp specific sequence was amplified by PCR from the genomic DNA of T. gondii. T. gondii-specific IgG positive rate in patients with leukemia and lymphoma were 16.0% (24/150) and 20.0% (30/150), respectively, which were significantly higher than that of healthy persons (6.4%, 7/110) (P < 0.05). IgM positive rate of the leukemia patients, lymphoma patients, and healthy persons was 2.7% (4/150), 1.3% (2/150), and 0.9% (1/110) (P > 0.05), respectively. No significant difference was found in IgM and CAg positive rate among leukemia patients, lymphoma patients, and healthy persons (P > 0.05). No specific band (529 bp) was detected in all samples.

Heat shock factor 1 is a transcription factor of Fas gene.

In mammalian cells, stress-induced expression of heat shock protein is controlled by heat shock factor 1 (HSF1). However, HSF1 functions as a regulator of additional genes. In this study, we observed that heat treatment effectively induced expression of Fas. Using bioinformatics, a high affinity and functional HSF1-binding element within the -1996/-1985 oligonucleotide of the 5'-flanking region of the Fas gene was found, and was determined by electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Exogenous expression of a constitutively activative HSF1, induced Fas gene transcription and protein synthesis in the absence of heat stress. Moreover, RNA interference-mediated HSF1 gene-silencing attenuated Fas expression in a heat-induced model. Our results suggested that HSF1 is an important transcription factor of Fas gene.

Noninvasive molecular imaging of hypoxia in human xenografts: comparing hypoxia-induced gene expression with endogenous and exogenous hypoxia markers.

Tumor hypoxia is important in the development and treatment of human cancers. We have developed a novel xenograft model for studying and imaging of hypoxia-induced gene expression. A hypoxia-inducible dual reporter herpes simplex virus type 1 thymidine kinase and enhanced green fluorescence protein (HSV1-TKeGFP), under the control of hypoxia response element (9HRE), was stably transfected into human colorectal HT29 cancer cells. Selected clones were further enriched by repeated live cell sorting gated for hypoxia-induced eGFP expression. Fluorescent microscopy, fluorescence-activated cell sorting, and radioactive substrate trapping assays showed strong hypoxia-induced expression of eGFP and HSV1-tk enzyme in the HT29-9HRE cells in vitro. Sequential micropositron emission tomography (PET) imaging of tumor-bearing animals, using the hypoxic cell tracer (18)F-FMISO and the reporter substrate (124)I-FIAU, yielded similar tumor hypoxia images for the HT29-9HRE xenograft but not in the parental HT29 tumor. Using autoradiography and IHC, detailed spatial distributions in tumor sections were obtained and compared for the following hypoxia-associated biomarkers in the HT29-9HRE xenograft: (124)I-FIAU, (18)F-FMISO, Hoechst (perfusion), lectin-TRITC (functional blood vessels), eGFP, pimonidazole, EF5, and CA9. Intratumoral distributions of (124)I-FIAU and (18)F-FMISO were similar, and eGFP, pimonidazole, EF5, and CA9 colocalized in the same areas but not in well-perfused regions that were positive for Hoechst and lectin-TRITC. In enabling the detection of hypoxia-induced molecular events and mapping their distribution in vivo with serial noninvasive positron emission tomography imaging, and multiple variable analysis with immunohistochemistry and fluorescence microscopy, this human xenograft model provides a valuable tool for studying tumor hypoxia and in validating existing and future exogenous markers for tumor hypoxia.

Response to multiple radiation doses of fibroblasts over-expressing dominant negative Ku70.

PURPOSE: To evaluate the response of cells over-expressing dominant negative (DN) Ku70 to single and multiple small radiation doses. METHODS AND MATERIALS: Clones of fibroblasts over-expressing DNKu70, DNKu70-7, DNKu70-11, and parental Rat-1 cells were irradiated under oxic or hypoxic conditions with single or multiple doses. Cells were trypsinized 0 or 6 h after irradiation to determine surviving fraction (SF). RESULTS: Oxic DNKu70-7 or -11 cells trypsinized 6 h after irradiation were 1.52 or 1.25 and 1.28 or 1.15 times more sensitive than oxic Rat-1 at SF of 0.5 and 0.1, respectively. Hypoxic DNKu70-7 or -11 cells trypsinized 6 h after irradiation were 1.44 or 1.70 and 1.33 or 1.51 times more sensitive than hypoxic Rat-1 at SF of 0.5 and 0.1, respectively. To the multiple doses, oxic and hypoxic DNKu70-7 or -11 cells were 1.35 or 1.37 and 2.23 or 4.61 times more sensitive than oxic and hypoxic Rat-1, respectively, resulting in very small oxygen enhancement ratios. Namely, enhancement caused by DNKu70 under hypoxia after multiple doses was greater than that under oxic conditions and greater than that after single dose. CONCLUSIONS: Over-expression of DNKu70 enhances cells' response to radiation given as a single dose and as multiple small doses. The enhancement after multiple doses was stronger under hypoxic than under oxic conditions. These results encourage the use of DNKu70 fragment in a gene-radiotherapy.

[Rhein lysinate induces apoptosis in breast cancer SK-Br-3 cells by inhibiting HER-2 signal pathway].

This study is to investigate the effect of rhein lysinate on inducing human breast cancer cell line SK-Br-3 apoptosis and the role of HER-2 signal pathway in the apoptosis. MTT assay was used to detect SK-Br-3 cell proliferation. Cell cycle and apoptosis were analyzed by flow cytometry. The protein expression and the protein phosphorylation of HER-2 signal pathway were detected by Western blotting. The level of HER-2 mRNA was detected by RT-PCR and the level of HER-2 expression was also detected by immunofluorescence cytochemical methods. The results showed that rhein lysinate remarkably inhibited breast cancer SK-Br-3 cell proliferation. The IC50 value for 48 h treatment was 85 micromol x L(-1). Apoptosis in SK-Br-3 cells was induced by rhein lysinate in a dose dependent manner. The protein expressions of HER-2, NF-KB, and the protein phosphorylation of HER-2 were downregulated, however the protein expression of p53 and p21 was upregulated after rhein lysinate treatment. The level of HER-2 mRNA decreased by using RT-PCR assay and the level of HER-2 expression was also decreased by using immunofluorescence cytochemical assay after rhein lysinate treatment. It can be concluded that rhein lysinate could inhibit SK-Br-3 cell proliferation and induce apoptosis. HER-2/NF-kappaB/p53/p21 signal pathway might be involved in this process. Rhein lysinate has a good prospect to be an adjuvant chemotherapeutic drug.

[Human HSF1 mutants and their applications].

Heat shock factor 1 (HSF1) is the key protein in regulating stress response. It can be activated under heat, oxidative or another stress conditions. Dominant-positive and dominant-negative HSF1 are two types of HSF1 mutants. Both of them gain the DNA binding activity in the absence of stress. In addition, dominant-positive HSF1 acquires transcriptional activity, which dominant-negative HSF1 does not acquire. In this paper, the progress of using these HSF1 mutants in the research of cancer, neurodegenerative disorders and cardiovascular diseases will be discussed.

[Inhibition of pulmonary fibrosis by doxycycline: an experiment with mice].

OBJECTIVE: To investigate the effect of doxycycline, an antimicrobial antibiotic inhibiting type IV collagenase, on the development of pulmonary fibrosis induced by bleomycin (BLM) in mice. METHODS: Gelatin zymography assay was used to detect the secretion of 72,000 and 92,000 type IV collagenase in HT-1080 cells and the activity of these enzymes in vitro. Experimental pulmonary fibrosis was induced by intra-tracheal administration of BLM in anesthetized mice. Total lung collagen content was determined by hydroxyproline assay. The histopathological changes of pulmonary fibrosis were evaluated by image analysis. RESULTS: The secretion of 72,000 and 92,000 type IV collagenase in HT-1080 cell was markedly inhibited by doxycycline at concentrations of 0.1 mg/ml and 0.05 mg/ml. The activity of type IV collagenase in vitro was also suppressed by doxycycline. The hydroxyproline level in the lung was decreased in mice treated with doxycycline at the dose of 100 mg/kg, down to 34.7% of that of the BLM model group. As shown by image analysis, the extensiveness of fibrotic lesions, the thickness of interalveolar septa, and the accumulation of nucleated cells were decreased in doxycycline treated group in comparison with BLM model group. CONCLUSION: This study provides evidence that doxycycline shows inhibitory effect on BLM induced pulmonary fibrosis.

[Chemosensitivity of mdr1 gene overexpressed multidrug resistant cancer cells to lidamycin].

AIM: To investigate the chemosensitivity to lidamycin (C-1027) in mdr1 gene overexpressing cancer cell lines established by drug induction and by gene-transfection. METHODS: DNA was cloned by RT-PCR and then eukaryotic expressing recombinant plasmid pcDNA3. 1/mdrl was constructed. Using Lipofectamine 2000, a strain of stably transfected human hepatoma cancer cells, HepG2/mdrl, was obtained. The mdr1 mRNA level, P-glycoprotein (P-gp) level and the activity of P-gp to extrude drugs in cancer cells were determined by RT-PCR, immunofluorescence analysis and rhodamine 123 efflux assay. The chemosensitivity of cancer cells with low or high mdr1 expression to lidamycin and other antitumor drugs was tested by MTT assay. RESULTS: The mdr1 mRNA and P-gp levels in KBv200, MCF-7/ADR, and stably transfected HepG2/mdr1 cells were much higher than that in respective parent KB, MCF-7 and HepG2 cells. The IC50 values of lidamycin for KBv200, MCF-7/ADR and HepG2/mdrl cells were (0.24 +/- 0.20) nmol x L(-1), (0.028 +/- 0.011) nmol x L(-1), and (0.020 +/- 0.011) nmol x L(-1), respectively. Compared with parental cells, the values of resistant fold for KBv200, MCF-7/ADR and HepG2/mdr1 cells to lidamycin were 6.8, 1.6 and 1.3 fold; to adriamycin were 37.2, 181.3 and 8.8 fold; to taxol were 336.8, 49.2 and 40.3 fold, respectively. CONCLUSION: Lidamycin is highly active to multidrug resistant cancer cells. The chemosensitivity of those resistant cancer cells to lidamycin is approximately at the similar level as that of parent cancer cells.

Antitumor activity of anti-type IV collagenase monoclonal antibody and its lidamycin conjugate against colon carcinoma.

AIM: Type IV collagenase including MMP-2 and -9 plays an important role in cancer cell invasion and metastasis and is an attractive target for mAb-directed therapy. The immunoreactivity of mAb 3G11, a mAb directed against type IV collagenase in human colorectal carcinomas, was studied by immuno-histochemical (IHC) staining. mAb 3G11 was conjugated to an antitumor antibiotic lidamycin (LDM). The antitumor activity of 3G11-LDM conjugate against colon carcinoma was investigated in mice. METHODS: ELISA, gelatin zymography, and Western blot assay were used for the biological characterization of mAb 3G11. The immunoreactivity of mAb 3G11 with human colorectal carcinomas was detected by IHC staining. The cytotoxicity of LDM and 3G11-LDM conjugate to human colon carcinoma HT-29 cells was examined by clonogenic assay and MTT assay. The therapeutic effect of conjugate 3G11-LDM was evaluated with colon carcinoma 26 in mice. RESULTS: As shown in ELISA, mAb 3G11 reacted specifically with type IV collagenase, while 3G11-LDM conjugate also recognized specifically its respective antigen. In IHC assay, mAb 3G11 showed positive immunoreactivity in most cases of colorectal carcinoma, and negative immunoreactivity in the adjacent non-malignant tissues. By gelatin zymography, the inhibition effect of mAb 3G11 on the secretion activity of type IV collagenase was proved. In terms of IC50 values in MTT assay, the cytotoxicity of LDM to human colon carcinoma HT-29 cells was 10,000-fold more potent than that of mitomycin C (MMC) and adriamycin (ADM). 3G11-LDM conjugate also displayed extremely potent cytotoxicity to human colon carcinoma HT-29 cells with an IC50 value of 5.6 x 10(-19) mol/L. 3G11-LDM conjugate at the doses of 0.05 and 0.1 mg/kg inhibited the growth of colon carcinoma 26 in mice by 70.3 and 81.2%, respectively. CONCLUSION: mAb 3G11 is immunoreactive with human colorectal carcinoma and its conjugate with LDM is highly effective against colon carcinoma in mice.

Antitumor efficacy of lidamycin on hepatoma and active moiety of its molecule.

AIM: To study the in vitro and in vivo antitumor effect of lidamycin (LDM) on hepatoma and the active moiety of its molecule. METHODS: MTT assay was used to determine the growth inhibition of human hepatoma BEL-7402 cells, SMMC-7721 cells and mouse hepatoma H22 cells. The in vivo therapeutic effects of lidamycin and mitomycin C were determined by transplantable hepatoma 22 (H22) in mice and human hepatoma BEL-7402 xenografts in athymic mice. RESULTS: In terms of IC(50) values, the cytotoxicity of LDM was 10 000-fold more potent than that of mitomycin C (MMC) and adriamycin (ADM) in human hepatoma BEL-7402 cells and SMMC-7721 cells. LDM molecule consists of two moieties, an aproprotein (LDP) and an enediyne chromophore (LDC). In terms of IC(50) values, the potency of LDC was similar to LDM. However, LDP was 10(5)-fold less potent than LDM and LDC to hepatoma cells. For mouse hepatoma H22 cells, the IC(50) value of LDM was 0.025 nmol/L. Given by single intravenous injection at doses of 0.1, 0.05 and 0.025 mg/kg, LDM markedly suppressed the growth of hepatoma 22 in mice by 84.7%, 71.6% and 61.8%, respectively. The therapeutic indexes (TI) of LDM and MMC were 15 and 2.5, respectively. By 2 iv. injections in two experiments, the growth inhibition rates by LDM at doses of 0.1, 0.05, 0.025, 0.00625 and 0.0125 mg/kg were 88.8-89.5%, 81.1-82.5%, 71.2-74.9%, 52.3-59.575%, and 33.3-48.3%, respectively. In comparison, MMC at doses of 5, 2.5, and 1.25 mg/kg inhibited tumor growth by 69.7-73.6%, 54.0-56.5%, and 31.5-52.2%, respectively. Moreover, in human hepatoma BEL-7402 xenografts, the growth inhibition rates by LDM at doses of 0.05 mg/kg X2 and 0.025 mg/kg X2 were 68.7% and 27.2%, respectively. However, MMC at the dose of 1.25 mg/kg X2 showed an inhibition rate of 34.5%. The inhibition rate of tumor growth by LDM was higher than that by MMC at the tolerated dose. CONCLUSION: Both LDM and its chromophore LDC display extremely potent cytotoxicity to hepatoma cells. LDM shows a remarkable therapeutic efficacy against murine and human hepatomas in vivo.