Analysis of tumor microenvironment alterations in partially responsive rectal cancer patients treated with neoadjuvant chemoradiotherapy.

PURPOSE: Achieving a pathologic complete response (pCR) after neoadjuvant chemoradiotherapy (NCRT) remains a challenge for most patients with rectal cancer. Exploring the potential of combining NCRT with immunotherapy or targeted therapy for those achieving a partial response (PR) offers a promising avenue to enhance treatment efficacy. This study investigated the impact of NCRT on the tumor microenvironment in locally advanced rectal cancer (LARC) patients who exhibited a PR. METHODS: This was a retrospective, observational study. Five patients demonstrating a PR after neoadjuvant treatment for LARC were enrolled in the study. Biopsy samples before treatment and resected specimens after treatment were stained with a panel of 26 antibodies targeting various immune and tumor-related markers, each labeled with distinct metal tags. The labeled samples were then analyzed using the Hyperion imaging system. RESULTS: Heterogeneity within the tumor microenvironment was observed both before and after NCRT. Notably, tumor-associated macrophages, CD4 + T cells, CD8 + T cells, CD56 + natural killer cells, tumor-associated neutrophils, cytokeratin, and E-cadherin exhibited slight increase in abundance within the tumor microenvironment following treatment (change ratios = 0.78, 0.2, 0.27, 0.32, 0.17, 0.46, 0.32, respectively). Conversely, the number of CD14 + monocytes, CD19 + B cells, CD45 + CD4 + T cells, collagen I, α-smooth muscle actin, vimentin, and ß-catenin proteins displayed significant decreases post-treatment (change ratios = 1.73, 1.92, 1.52, 1.25, 1.52, 1.12, 2.66, respectively). Meanwhile, Foxp3 + regulatory cells demonstrated no significant change (change ratio = 0.001). CONCLUSIONS: NCRT has diverse effects on various components of the tumor microenvironment in LARC patients who achieve a PR after treatment. Leveraging combination therapies may optimize treatment outcomes in this patient population.

Lentivirus-mediated short hairpin RNA interference of CENPK inhibits growth of colorectal cancer cells with overexpression of Cullin 4A.

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignant tumors worldwide. The identification of novel diagnostic and prognostic biomarkers for CRC is a key research imperative. Immunohistochemical analysis has revealed high expression of centromere protein K (CENPK) in CRC. However, the role of CENPK in the progression of CRC is not well characterized. AIM: To evaluate the effects of knockdown of CENPK and overexpression of Cullin 4A (CUL4A) in RKO and HCT116 cells. METHODS: Human colon cancer samples were collected and tested using a human gene expression chip. We identified CENPK as a potential oncogene for CRC based on bioinformatics analysis. In vitro experiments verified the function of this gene. We investigated the expression of CENPK in RKO and HCT116 cells using quantitative polymerase chain reaction (qPCR), western blot, and flow cytometry. The effect of short hairpin RNA (shRNA) virus-infected RKO cells on tumor growth was evaluated in vivo using quantitative analysis of fluorescence imaging. To evaluate the effects of knockdown of CENPK and overexpression of CUL4A in RKO and HCT116 cells, we performed a series of in vitro experiments, using qPCR, western blot, MTT assay, and flow cytometry. RESULTS: We demonstrated overexpression of CENPK in human colon cancer samples. CENPK was an independent risk factor in patients with CRC. The downstream genes FBX32, CUL4A, and Yes-associated protein isoform 1 were examined to evaluate the regulatory action of CENPK in RKO cells. Significantly delayed xenograft tumor emergence, slower growth rate, and lower final tumor weight and volume were observed in the CENPK short hairpin RNA virus infected group compared with the CENPK negative control group. The CENPK gene interference inhibited the proliferation of RKO cells in vitro and in vivo. The lentivirus-mediated shRNA interference of CENPK inhibited the proliferation of RKO and HCT116 colon cancer cells, with overexpression of the CUL4A. CONCLUSION: We indicated a potential role of CENPK in promoting tumor proliferation, and it may be a novel diagnostic and prognostic biomarker for CRC.

Surgical Treatment of Lateral Tibial Plateau Fractures Involving the Posterolateral Column.

OBJECTIVE: To summarize the indications and the clinical effects of a transfibular neck osteotomy approach and a combined anterolateral and posterolateral approach in the treatment of fractures of the lateral tibial plateau involving the posterolateral column. METHODS: Eleven patients with lateral tibial plateau fractures were included in the present study. The fractures were Schatzker type II or lateral platform fractures involving posterolateral column. The anterolateral combined posterolateral approach (lateral + posterolateral locking plate fixation) was applied in 7 patients and 4 patients underwent transfibular neck osteotomy (lateral + posterolateral locking plate fixation + 1/4 tubular plate edge fixation, fibular osteotomy with Kirschner wire tension band fixation, and hollow nail fixation for upper tibiofibular joint). All cases were followed up for 12-24 months, with an average follow-up of 17.5 ± 5.0 months. At the last followup, the Rasmussen radiological criteria were used to evaluate the effect of fracture reduction and fixation. The knee joint function was evaluated using the knee function evaluation criteria of the Hospital for Special Surgery (HSS). The Lachman test and the pivot-shift test were used to evaluate the anterior and posterior and rotational stability of the knee joint. The range of knee motion was recorded. RESULTS: Bone healing was achieved in all patients with fractures treated with a transfibular neck osteotomy approach and a combined anterolateral and posterolateral approach. At the last follow-up, both the Lachman test and the pivot-shift test results were negative. All patients had complete knee extension. For the combined anterolateral and posterolateral approach, the knee flexion angle was 110°-130°, with an average of 122.86° ± 7.56°. For the transfibular neck osteotomy approach, the knee flexion angle was 115°-130°, with an average of 120.00° ± 7.07°. For the patients in which the combined anterolateral and posterolateral approach was used, the Rasmussen score was 12-18 points, with an average of 16.00 ± 2.56 points. The results were excellent in 4 cases and good in 3 cases; therefore, 100% of results were excellent or good. For patients in which the transfibular neck osteotomy approach was used, the Rasmussen score was 10-18 points, with an average of 15.25 ± 3.77 points. The results were excellent in 2 cases, good in 1 case, and acceptable in 1 case; therefore, 75% of results were excellent or good. The HSS score for the combined anterolateral and posterolateral approach was 76-98 points, with an average of 88.43 ± 7.55 points. The results were excellent in 5 cases and good in 2 cases; therefore, 100% of results were excellent or good. The HSS score for the transfibular neck osteotomy approach was 74-96 points, with an average of 87.25 ± 9.43 points. The results were excellent in 3 cases and good in 1 case; therefore, 100% of results were excellent or good. There were no significant differences in operation time, surgical blood loss, fracture healing time, postoperative imaging score, and knee function evaluation between the two approaches. One patient who underwent transfibular neck osteotomy had a 3-mm step that gradually appeared, but no significant abnormalities were found in the width of the platform and the lower limb force line. One patient in whom the combined anterolateral and posterolateral approach was used showed numbness in the common peroneal nerve. No common peroneal nerve injury occurred through the transfibular neck osteotomy approach. CONCLUSIONS: The anterolateral combined posterolateral approach and the transfibular neck osteotomy approach are effective in the surgical treatment of lateral tibial plateau fractures involving the posterolateral column. However, the transfibular neck osteotomy approach is more suitable for the posterolateral plateau articular surface damaged with bone separation and displacement, deep collapse, cases involving a large range of the posterolateral column, especially fractures of the lateral tibial plateau in the upper tibiofibular syndesmosis area of the line connecting the anterior and posterior margin of the fibular head to the midpoint of the plateau.

Overexpression of DNMT1 leads to hypermethylation of H19 promoter and inhibition of Erk signaling pathway in disuse osteoporosis.

Disuse osteoporosis (DOP) is a common complication of the lack of mechanical loading. The precise mechanism underlying DOP remains unknown, although epigenetic modifications may be a major cause. Recently, cumulative research has revealed that DNA methyltransferase (DNMT) proteins can catalyze the conversion of cytosine to 5-methylcytosine (5mC), altering the epigenetic state of DNA. Here, we report that DNMT1 expression and lncRNA-H19 methylation are upregulated in the femoral tissues of DOP rats, accompanied with inhibited Erk signaling pathway. Overexpression of DNMT1 in UMR-106 cells mimics 5mC enrichment in the H19 promoter, inhibition of Erk signaling and impairment of osteogenesis, which can be rescued by 5'-aza-deoxycytidine (5'-Aza) treatment. Moreover, local intramedullary injection of Dnmt1 siRNA (siDNMT1) in Sprague-Dawley (SD) rats abrogated disuse lncRNA-H19 (H19) downregulation, Erk signaling inhibition, histopathological changes, and bone microstructure declines in the distal femur in vivo. Therefore, our data identify for the first time a new signaling cascade in DOP: mechanical unloading causes upregulation of DNMT1 and hypermethylation of H19 promoter, which subsequently leads to downregulation of lncRNA-H19 and inhibition of the ERK signaling, suggesting a new potential therapeutic target.

LncRNA-H19 Modulates Wnt/ß-catenin Signaling by Targeting Dkk4 in Hindlimb Unloaded Rat.

OBJECTIVE: To investigate the biological functions of long noncoding RNA-H19 (H19) in the pathogenesis of disuse osteoporosis (DOP). METHODS: Fifty-four male Sprague Dawley (SD) rats were randomly divided into three groups: baseline control (BC, 6), age-matched control (AC, 24), and hindlimb unloading (HLU, 24). The rats in the BC group were sacrificed at the beginning of the experiment, while the AC and HLU rats were sacrificed at different times (7, 14, 21 and 28 days after HLU). The DOP model was verified by micro-CT scan, and quantitative real-time polymerase chain reaction (qRT-PCR) was used to quantify the expression of osteogenic genes (OPG, RunX2 and OPG). Gene sequencing and bioinformatic analysis were performed to find H19 target genes and the associated signaling pathway, which were first verified on tissue samples. Further verification was performed by knocking down the H19 and related gene in rat osteoblast cell line (UMR106 cell). Then, the changes of associated signaling pathway and osteogenic function were examined to confirm the prediction of the bioinformatic analysis. RESULTS: Micro-CT scans and quantitative real-time polymerase chain reaction (qRT-PCR) tests showed progressively deteriorated trabecular bone and decreased level of osteogenic genes in the metaphysis of distal femur during HLU, indicating the successful establishment of a DOP model. According to RNA sequencing, 1351 mRNA and 464 lncRNA were abnormally expressed in response to mechanical unloading, in which the H19 decreased 2.86 fold in HLU rats. There were 1426 mRNA predicted to be the target genes of H19, and KEGG pathway analysis suggested that Wnt signaling pathway (Wnt signaling) was the top pathway responsible for these target genes. In the Wnt-associated genes targeted by H19, 11 were differentially expressed between HLU and AC rats, among which Dkk4 increased 2.44 fold in HLU rats when compared to normal controls. These results of sequencing and bioinformatic analysis were confirmed by the low expression of H19, overexpression of Dkk4 and inhibited Wnt signaling observed in DOP rats. Subsequent in vitro cell assay further demonstrated that knockdown of H19 led to upregulation of Dkk4, and inhibition of Wnt signaling and osteogenic function in UMR106 cell. These effects can be greatly reversed after application of knocking down Dkk4. CONCLUSION: Our findings demonstrated that low expression of H19, induced by mechanical unloading, leads to development of DOP through inhibition of Wnt signaling by promoting Dkk4 expression.

TET3 Mediates Alterations in the Epigenetic Marker 5hmC and Akt pathway in Steroid-Associated Osteonecrosis.

Steroid-associated osteonecrosis (SAON) is one of the common complications of clinical glucocorticoid (GC) administration, with osteocyte apoptosis appearing as the primary histopathological lesion. However, the precise mechanism underlying SAON remains unknown. Epigenetic modification may be a major cause of SAON. Recently, cumulative research revealed that Ten-Eleven Translocation (TET) proteins can catalyze the conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) and then alter the epigenetic state of DNA. Here, we report that TET3-5hmC was upregulated in the femoral head tissues of SAON patients and MLO-Y4 cells with dexamethasone (Dex) treatment. Knockdown of TET3 in MLO-Y4 cells decreased 5hmC enrichment and rescued Dex-induced apoptosis. Meanwhile, the local intramedullary injection of TET3 siRNA in Sprague-Dawley rats abrogated GC-induced osteocyte apoptosis, histopathological changes, abnormal MRI signals, and bone microstructure declines in the femoral head in vivo. Moreover, a hydroxymethylated DNA immunoprecipitation (hMeDIP)-chip analysis of Dex-treated osteocytes revealed 456 different 5hmC-enriched genes. The Akt pathway was found to mediate the functional effect of Dex-induced dynamic 5hmC change; this was further verified in clinical samples. The loss of TET3 in MLO-Y4 cells abrogated Dex-induced Akt signaling pathway inhibition. Therefore, our data for the first time identify the effect of TET3-5hmC on the Akt pathway and the necessity of this signaling cascade in SAON, identifying a new potential therapeutic target. © 2016 American Society for Bone and Mineral Research.

Jaspiferin G, a new isomalabaricane-type triterpenoid from the sponge Jaspis stellifera.

A new isomalabaricane-type triterpenoid, jaspiferin G (1), together with four known isomalabaricane-type triterpenoids, isogeoditin A (2), 13-(E)-isogeoditin A (3), jaspolide E (4), and 22,23-dihydrostellettin D (5), was isolated from the marine sponge Jaspis stellifera. The structures were elucidated on the basis of spectroscopic data ((1)H and (13)C NMR, (1)H(-1)H COSY, HSQC, HMBC, and ROESY) and mass spectrometry.

Two new eunicellin diterpenoids from the East China Sea gorgonian Muricella sp.

A phytochemical investigation on gorgonian Muricella sp. from East China Sea resulted in the isolation of eight eunicellin diterpenoids including two new ones, muricellins A-B (1, 2). Chemical structures of these compounds were elucidated by spectroscopic techniques (1D and 2D NMR and MS) and by comparison with data reported in the literature. Anti-rheumatoid arthritis activities of 1, 3, 4, and 6 have been evaluated.

Three new polyunsaturated lipids from a Guangxi marine sponge Haliclona sp.

Three new polyunsaturated lipids, (6Z,9Z,12Z,15Z)-octadeca-6,9,12,15-tetraen-3-one (1), (6Z,9Z,12Z,15Z)-1-bromooctadeca-6,9,12,15-tetraen-3-one (2), and (Z)-ethyl docos-5-enoate (3), together with two known polyunsaturated lipids, 4(Z),7(Z),10(Z)-tridecatrienoic acid (4) and (6Z,9Z,12Z,15Z)-octadeca-1,6,9,12,15-pentaen-3-one (5), were isolated from the marine sponge Haliclona sp., which was collected from Guangxi, using HSCCC and HPLC methods. Chemical structures of the five compounds were elucidated by spectroscopic techniques.

Jaspiferins C-F, four new isomalabaricane-type triterpenoids from the South China Sea sponge Jaspisstellifera.

A chemical investigation of marine sponge Jaspis stellifera, collected from the South China Sea, led to the isolation of four new isomalabaricane-type triterpenoids, jaspiferins C-F (1-4). The structures of those compounds were elucidated by extensive spectroscopic methods. Jaspiferin C (1), which has the six-membered carbon ring at the side chain, was discovered for the first time from the isomalabaricane-type triterpenoids. The hypothesis of a biogenetic pathway to generate jaspiferin C (1) was depicted.

Novel polyhydroxylated steroids from the East China Sea gorgonian Echinogorgia sassapo reticulata with suppressive activity of leukotriene C4 generation and degranulation in bone marrow-derived mast cells.

The gorgonian Echinogorgia sassapo reticulata contains two new bioactive polyhydroxylated steroids, sassapols A (1), B (2), and five related known compounds (3-7). Compound 6 has been encountered for the first time in natural sources. The structures of these new compounds were defined by spectroscopic analysis. All the compounds (1-7) isolated from E. sassapo reticulata were tested for anti-inflammatory activity. Compounds 1, 3, 5, and 7 inhibited both the generation of leukotriene C4 and the degranulation reaction in mouse bone marrow-derived mast cells.

[Effects of Dioscorea septemloba on the biomechanical and bone histomorphometric parameters of femur in the ovariectomized rats].

OBJECTIVE: To investigate the effects of the decoction of Rhizoma Dioscoreae septemlobae (RD) on the biomechanical and bone histomorphometric parameters of femur in the ovariectomized rats. METHODS: 25 female Wistar rats without pregnancy and deliver were divided into 5 groups randomly: sham (sham-operation), ovariectomy (OVX), OVX + high dosage RD (4 g/kg x d), OVX + middle dosage RD (2 g/kg x d) and OVX + low dosage RD (1 g/kg x d), n = 5 in every group. After intragastric administration 12-week period continuously, the biomechanical and the bone histomorphometric parameters of the femur of the rats in every group were determined, respectively, including percentage of trabecular bone volume (TBV%), percentage of trabecular osteoid (TOS%), mean osteoid width (MOSW), percentage of mineralizing surface (MdS%), percentage of double mineralizing surface (DMds%), percentage of DMds/MdS (%), percentage of travecular formation surface (TFS%), percentage of trabecular resorption surface (TRS%), mineral apposition rate (MAR), mineralizing lag time (MLT). RESULTS: The maximum loading, deflection, the maximum strain of the femur in the OVX group was 125.78 +/- 15.48 (N), 1.87 +/- 0.22 (mm), 9.34 +/- 1.10 (%), it was significantly lower than that in the sham group ( P< 0.05, P < 0.01), respectively. The maximum loading and maximum stress was increased in different extent in the every dose group of OVX + RD, respectively. TBV% of femur was significantily lower in the OVX group than that in the sham group (P < 0.01). The MdS%, DMds%, DMds/MdS (%), TOS%, MOSW, TRS%, MAR was significantly higher in the OVX group than that in the sham group, respectively (P < 0.01). In the RA high and middle dosage group, the TBV% of femur was significantly higher than that in the model group (P < 0.05), and the MdS%, DMds%, DMds/MdS (%), TRS%, TOS%, MOSW, MAR was significantly lower than that in the model group, respectively (P < 0.05), and MLT was decurtated slightly (P > 0.05). CONCLUSION: The decoction of RD can decline the bone turnover and the loss of bone of femur in the ovariectomized rats.

[Effects of Dioscorea septemloba on bone metabolism in ovariectomized rats].

OBJECTIVE: To investigate the effects of the decoction of Rhizoma Dioscorea septemlobae (RD) on the bone metabolism in ovariectomized rats. METHOD: Thirty female, 3-month-old Wistar rats without pregnancy and deliver were randomly divided into 6 groups: sham (sham-operation), ovariectomy (OVX), OVX + diethylstilbestrol, OVX + high dose RD (4 g x kg(-1) x d(-1)), OVX + middle dose RD (2 g x kg(-1) x d(-1)) and OVX + low dose RD (1 g x kg(-1) x d(-1)) (n = 5 in every group). After 12-week period of continuous treatment, the urinary samples and blood samples were collected for the determination of serum estrodiol (E2), calcium (Ca), phosphorus (P), bone glaprotein (BGP), alkaline phosphatase (ALP), urinary calcium/creatinine (Ca/Cr), phosphorus/ creatinine (P/Cr) and deoxypyridioline/creatinine (DPD/Cr). The uteri were removed and weighed. The bone mineral density (BMD) and the biomechanical parameters of the femur of the rats in every group were determined, respectively. RESULT: The coefficient of uteri in every dose group of OVX + RD was significantly higher than that in the OVX group (P < 0.01). The concentration of serum ALP, BGP and urinary DPD/Cr, Ca/Cr in the OVX group was significantly higher than that in the sham group (P < 0.05), respectively, However, that in the every dose of OVX + RD was lower than that in the OVX group, respectively. There was no significan difference in the concentration of serum Ca, P and urinary P/Cr in every group, respectively. The bone mineral density (BMD) in the OVX group was (0.032 +/- 0.007) g x cm(-2) and was significantly lower than that in the sham group (P < 0.01). However, the value in the group of every dose OVX + RD was significantly higher than that in the OVX group (P < 0.05, P < 0.01), respectively. The maximum loading, deflection and the maximum strain of the femur in the OVX group were (125.78 +/- 15.48) N, (1.87 +/- 0.22) mm, (9.34 +/- 1.10) % and were significantly lower than those in the sham group (P < 0.05, P < 0.01), respectively. The maximum loading and maximum stress were increased in different extent in the every dose group of OVX + RD, respectively. CONCLUSION: The decoction of RD can inhibit bone absorption, decline bone turnover and improve the loss of bone in ovariectomized rats.

[A comparison study on clinical chromatographic fingerprintings of mycolic acids analysis of 18 standard strains of Mycobacteria in China].

OBJECTIVE: A clinical chromatographic fingerprinting of 18 standard strains of Mycobacteria commercialized in China by high-performance liquid chromatography approach was developed and improved in this laboratory. A comparison of clinical chromatographic fingerprintings of mycolic acids was carried out. METHODS: Mycolic acids were extracted from whole cultured cells of Mycobacteria by biochemical methods, and then samples was prepared for analysis after the mycolic acids were saponified, acidified and derived. The samples were detected by high-performance liquid chromatography under optimum conditions. RESULTS: Using above techniques a clinical chromatographic fingerprinting of Mycolic acids analysis was successfully established. The repeatability of the mycolic acids fingerprinting was evaluated. Coefficient of variation (CV) of chromatographic fingerprinting was between 0.20% - 0.83%. CONCLUSIONS: The first clinical chromatographic fingerprinting of 18 standard strains of Mycobacteria in China was established in this laboratory. Mycobacteria can be accurately identified according to chromatographic fingerprinting in a short time. Moreover, there was significant difference between BCG vaccine and Mycobacterium bovis when their peak was compared, which may lead to research of new tools for identifying insidious infection of tuberculosis and for the study of the mechanism of drug tolerance.