PROTACs in Epigenetic Cancer Therapy: Current Status and Future Opportunities.

The epigenetic regulation of gene functions has been proven to be strongly associated with the development and progression of cancer. Reprogramming the cancer epigenome landscape is one of the most promising target therapies in both treatments and in reversing drug resistance. Proteolytic targeted chimeras (PROTACs) are an emerging therapeutic modality for selective degradation via the native ubiquitin-proteasome system. Rapid advances in PROTACs have facilitated the exploration of targeting epigenetic proteins, a lot of PROTAC degraders have already been designed in the field of epigenetic cancer therapy, and PROTACs targeting epigenetic proteins can better exploit target druggability and improve the mechanistic understanding of the epigenetic regulation of cancer. Thus, this review focuses on the progress made in the development of PROTAC degraders and PROTAC drugs targeting epigenetics in cancer and discusses challenges and future opportunities for the field.

Elastic Net-Based Identification of a Multigene Combination Predicting the Survival of Patients with Cervical Cancer.

BACKGROUND The objective of the present study was to identify prognostication biomarkers in patients with cervical cancer. MATERIAL AND METHODS Survival related genes were identified in The Cancer Genome Atlas (TCGA) cervical cancer study, and they were included into an elastic net regularized Cox proportional hazards regression model (CoxPH). The genes that their coefficients that were not zero were combined to build a prognostication combination. The prognostication performance of the multigene combination was evaluated and validated using Kaplan-Meier curve and univariate and multivariable CoxPH model. Meanwhile, a nomogram was built to translate the multigene combination into clinical application. RESULTS There were 37 survival related genes identified, 9 of which were integrated to build a multigene combination. The area under the curve (AUC) of receiver operating characteristic (ROC) curve at 1-year, 3-year, 5-year, and 7-year in the training set were 0.757, 0.744, 0.799, and 0.854, respectively, and the multigene combination could stratify patients into significantly different prognostic groups (hazard ratio [HR]=0.2223, log-rank P<0.0001). Meanwhile, the corresponding AUCs in the test set was 0.767, 0.721, 0.735, and 0.703, respectively, and the multigene combination could classify patients into different risk groups (HR=0.3793, log-rank P=0.0021). The multigene combination could stratify patients with early stage and advanced stage into significantly different survival groups in the training set and test set. The prognostication performance of the multigene combination was better compared with 3 existing prognostic signatures. Finally, a multigene containing nomogram was developed. CONCLUSIONS We developed a multigene combination which could be treated as an independent prognostic factor in cervical cancer and be translated into clinical application.

[Effect of curcumin on radiosensitization of CNE-2 cells and its mechanism].

OBJECTIVE: To investigate the effect of curcumin (Cur) on radiosensitivity of nasopharyngeal carcinoma cell CNE-2 and its mechanism. METHOD: The effect of curcumin on radiosensitivity was determined by the clone formation assay. The cell survival curve was fitted by Graph prism 6. 0. The changes in cell cycle were analyzed by flow cytometry (FCM). The differential expression of long non-coding RNA was detected by gene chip technology. Part of differentially expressed genes was verified by Real-time PCR. RESULT: After 10 micro mol L-1 Cur had worked for 24 h, its sensitization enhancement ratio was 1. 03, indicating that low concentration of curcumin could increase the radiosensitivity of nasopharyngeal carcinoma cells; FCM displayed a significant increase of G2 phase cells and significant decrease of S phase cells in the Cur combined radiation group. In the Cur group, the GUCY2GP, H2BFXP, LINC00623 IncRNA were significantly up-regulated and ZRANB2-AS2 LOC100506835, FLJ36000 IncRNA were significantly down-regulated. CONCLUSION: Cur has radiosensitizing effect on human nasopharyngeal carcinoma CNE-2 cells. Its mechanism may be related to the changes in the cell cycle distribution and the expression of long non-coding IncRNA.

Stapled peptide PROTAC induced significantly greater anti-PD-L1 effects than inhibitor in human cervical cancer cells.

Introduction: Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that target immune checkpoints that suppress immune cell activity. Low efficiency and high resistance are currently the main barriers to their clinical application. As a representative technology of targeted protein degradation, proteolysis-targeting chimeras (PROTACs) are considered to have potential for addressing these limitations. Methods: We synthesized a stapled peptide-based PROTAC (SP-PROTAC) that specifically targeted palmitoyltransferase ZDHHC3 and resulted in the decrease of PD-L1 in human cervical cancer cell lines. Flow cytometry, confocal microscopy, protein immunoblotting, Cellular Thermal Shift Assay (CETSA), and MTT assay analyses were conducted to evaluate the effects of the designed peptide and verify its safety in human cells. Results: In cervical cancer celllines C33A and HeLa, the stapled peptide strongly downregulated PD-L1 to < 50% of baseline level at 0.1 µM. DHHC3 expression decreased in both dosedependentand time-dependent manners. MG132, the proteasome inhibitor, can alleviate the SP-PROTAC mediated degradation of PD-L1 in human cancer cells. In a co-culture model of C33A and T cells, treatment with the peptide induced IFN-γ and TNF-α release in a dose-dependent manner by degrading PD-L1. These effects were more significant than that of the PD-L1 inhibitor, BMS-8. Conclusions: Cells treated with 0.1 µM of SP-PROTAC or BMS-8 for 4 h revealed that the stapled peptide decreased PD-L1 more effectively than BMS-8. DHHC3-targeting SP-PROTAC decreased PD-L1 in human cervical cancer more effectively than the inhibitor BMS-8.

[Analysis of cervical HPV infection in HIV positive Chinese women].

OBJECTIVE: To investigate prevalence HPV infections in cervix among HIV-infected Chinese women. METHODS: From September 2009 to May 2011, 293 women with positive HIV underwent cervical cancer screening as study group matched with 200 women with negative HIV as control group. Questionnaires including demographic information and HIV associated information were collected, Pap smear and 23 subtype of HPV were performed in those women. The women with positive HPV were followed up per 6 months, and the period of following up were more than 12 months. Binary logistic analysis was used for high risk factors of HPV persistent infection. RESULTS: Prevalent HPV infection was 44.4% (130/293) in study group and 20.0% (40/200) in control group, respectively, which reached statistical difference (P < 0.05). The most common genotype of HPV was HPV 16, which prevalence was 13.7% (40/293) in study group and 7.0% (14/200) in control group. The other HPV subtype prevalence was HPV-58, HPV-52, HPV-43 and HPV-18, which was 9.2% (27/293), 8.2% (24/293), 8.2% (24/293), 6.8% (20/293) in study group and 3.0% (6/200), 2.5% (5/200), 1.5% (3/200), 2.5% (5/200) in control group. At time point of 12 months following up, the persistent prevalence of HPV was 47.5% (48/101) in study group and 21.1% (8/38) in control group, which reached statistical difference (P < 0.05). Multiple HPV infections (OR = 6.4, 95%CI: 1.6 - 25.6), abnormal cytology (OR = 18.1, 95%CI: 4.5 - 76.9) and lower CD(4) T cell count (compared with CD(4) > 3.5 × 10(8)/L, if 2.0 × 10(8) ≤ CD(4) ≤ 3.5 × 10(8), OR = 8.1, 95%CI: 1.3 - 56.3; if CD(4) < 2.0 × 10(8)/L, OR = 9.1, 95%CI: 1.8 - 46.9) were independently associated with HPV persistence among HIV-positive subjects. CONCLUSIONS: Prevalence and persistence of HPV infections were more common among HIV-positive Chinese women than those in HIV-negative Chinese women. Improving immune function, decreasing multiple HPV infections, treating abnormal cervical cytology could decrease prevalence of HPV infection.

[Experimental research on prevention and treatment of fatty liver rats with Abrus cantoniensis].

OBJECTIVE: To investigate the effects of Abrus cantoniensis (AC) on blood lipid metabolism, pathomorphological change of the liver and fenestrae of liver sinus endothelial cell (LSEC) in fatty liver disease rats. METHODS: SD rats were divided into 7 groups: blank control group,fatty liver model group, simvastatin group (7.2 mg/kg), Gynostemma pentaphyllum group (16.2 mg/kg), high dose (40 g/kg), middle dose (20 g/kg) and low dose (10 g/kg) of AC groups. All rats except blank control group were fed with high fat diet for the first 3 weeks, then treated with different conditions as previously mentioned for the next 3 weeks while keep on feeding with high fat diet. At the 43rd day,the abdominal aortic blood was collected for measuring the serum concentration of AST, ALT, TC, TG, HDL-C, LDL-C, and liver tissues were taken to make pathological sections for observation by optical microscope or were prepared for scanning electronic microscope. RESULTS: The levels of AST, ALT, TC, TG, LDL-C were obviously decreased while HDL-C were increased in fatty liver rats by AC high dose. Meanwhile the cell morphology of liver tissues and the fenestraes of LSEC were improved as well. CONCLUSION: AC can ameliorate the levels of blood lipid in fatty liver rats and improve the pathological change of liver tissues. To some extent AC has the function of prevention and treatment of fatty liver.

A review of recent advances on single use of antibody-drug conjugates or combination with tumor immunology therapy for gynecologic cancer.

Immune checkpoint inhibitors have made significant progress in the treatment of various cancers. However, due to the low ICI responsive rate for the gynecologic cancer, ICI two-drug combination therapy tends to be a predominant way for clinical treatment. Antibody-drug conjugates, a promising therapeutic modality for cancer, have been approved by the FDA for breast cancer, lymphoma, multiple myeloma and gastric cancer. On September 2021, the FDA granted accelerated approval to tisotumab vedotin for patients with recurrent or metastatic cervical cancer. Currently, the role of therapy of ADCs on gynecologic tumors was also included in medication regimens. Now more than 30 ADCs targeting for 20 biomarkers are under clinical trials in the field, including monotherapy or combination with others for multiple lines of therapy. Some ADCs have been proved to enhance the antitumor immunity effect on both pre-clinical models and clinical trials. Therefore, combination of ADCs and ICIs are expected in clinical trials. In this review, we discuss current development of ADCs in gynecologic oncology and the combination effects of ICIs and ADCs.

Proteomic analysis of protective effects of polysaccharides from Salvia miltiorrhiza against immunological liver injury in mice.

This study was designed to investigate mechanisms of the protective effects of Salvia miltiorrhiza polysaccharide (SMPS) against lipopolysaccharide (LPS)-induced immunological liver injury (ILI) in Bacille Calmette-Guérin (BCG)-primed mice. Two-dimensional difference gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis showed that three proteins are down-regulated and six proteins are up-regulated by SMPS. SMPS reduces the degree of liver injury by up-regulating the enzymes of the citric acid cycle, namely malate dehydrogenase (MDH) and 2-oxoglutarate dehydrogenase complex. LPS significantly increases nuclear factor kappa B (NF-κB) activation, inducible nitric oxide synthase (iNOS) expression and MDA level in BCG primed mice liver, whereas SMPS treatment protects against the immunological liver injury through inhibition of the NF-κB activation by up-regulation of PRDX6 and the subsequent attenuation of lipid peroxidation, iNOS expression and inflammation.

Trends in cervical cancer in young women in Hubei, China.

AIMS: This study was performed to determine whether the incidence of cervical cancer in women aged 35 or younger has changed for the past 30 years and to examine the clinical characteristics of the cases. METHODS: The clinical and pathological data of 6257 patients with cervical cancer treated between January 1975 and December 2009 were retrospectively analyzed. RESULTS: The prevalence of young (≤ 35 years old) patients steadily increased from 2.8% to 15.7% for the past 30 years. The ratio of adenocarcinoma also rose from 1975-1979 to 2005-2009. In an analysis by age group, in group A, adenocarcinoma was found in 17% (≤ 35 years old); in group B, 7.1% (> 35 years old) [χ² = 78.92, P < 0.0001]. The clinical presentation presented showed that 36.4% of patients presented mainly postcoital bleeding in group A, whereas the symptom of irregular genital bleeding predominated in group B (P < 0.0001). The patients detected by routine cytological screening in group A (8.7%) were more than the patients in group B (3%). CONCLUSIONS: The prevalence of cervical cancer in young women has been increasing steadily in Hubei, China. It is necessary for all sexually active women and women aged 35 years or even younger to undergo cervical cancer screening.

[Analysis of the relative distribution and gene variation of HPV16 transforming gene at different stages of cervical lesions].

OBJECTIVE: The aim of this study was to analyze the relative distribution and gene variation of HPV16 transforming gene E6, E7 and E5 at different stages of cervical lesions. METHODS: DNA was extracted from tissue samples of 200 patients with cervical lesions, including 124 cervical cancer, 17 CIN grade I and II, 23 CIN grade III and 36 cervicitis. Then HPV16 E6, E7 and E5 genes were amplified, and part of the E6 and E7 PCR products were sequenced using the HPV16 E6 and E7 specific primers. RESULTS: The positive rate of E6 gene in cervicitis, CINI and CINII, CINIII and cervical cancer was 25.0%, 29.4%, 60.9% and 76.6%, respectively. The positive rate of E7 gene was 16.7%, 41.2%, 43.5% and 61.3%, respectively. The positive rate of E5 gene was 5.6%, 5.9%, 30.4% and 40.3%, respectively. HPV16 E6 gene mutations in Nt 178 were found in 47 case from 80 cervical cancer samples, resulting in amino acid change of Asp to Glu. The mutation rate was 58.8%.Otherwise the mutation rate of E6 178 in cervicitis and CIN I approximately III samples was 25.0% and 31.8%. E7 mutations were found in Nt 647 in 21 cervical samples from 30 cervical cancer samples, resulting in amino acid change of Asn to Ser. The mutation rate was 70.0%. The mutation rate of E6 647 in cervicitis and CINI approximately III samples was 35.0% and 40.9%, respectively. CONCLUSION: The positive rate of E6 and E7 increase gradually from cervicitis, CINI and CINII, CINIII to cervical cancer. The rate of E5 is relatively lower than that of E6 and E7 gene in cervical tissue samples. These results show that E6 and E7 gene are highly associated with the progress of cervical cancer and E5 genes are lost in the development of cervical cancer. High frequency mutations of HPV16 E6 and E7 gene in E6 178, E7 647 have been found in cervical cancer samples in Hubei province, China. These results approved that the HPV16 variants prevalent in this area are different from the European and African variants.

[Clinical report of the modified Piver class III hysterectomy on invasive cervical cancer].

OBJECTIVE: To explore the surgical extent and to improve the surgical techniques of the Piver class III hysterectomy on invasive cervical cancer, so as to reduce the urinary tract complications, shorten the surgical duration, decrease the hemorrhage and blood transfusion. METHODS: The study group, 196 cases with stages Ib and IIa carcinoma of the cervix underwent the modified Piver class III hysterectomy from June 2000 to May 2005. The control group, 176 cases of the same stages underwent the Piver class III hysterectomy between June 1994 and May 1999. The modified Piver class III hysterectomy mainly include the surgical extent and some surgical techniques as follows. The cervicovesical and vesicovaginal space are separated with assistance of electrotome. Half of the uterosacral ligaments are removed with electrotome. The tunnel of the ureters is separated and penetrated or not. The anterior leaf of the cervicovesical ligaments is removed and the uterine artery are removed at the same time, while the ureter branch from the uterine artery are preserved. When the ureters are drawn to the lateral side of the body with an "S" hook and the urocyst lateral recessus are expanded, the cardinal ligaments can be exposed and be removed of 3/4. But part of the inferior of these ligaments should be preserved. The paracolpium are resected about 2 cm, 2 - 3 cm tissue of the vagina is removed. RESULTS: Compare with the control group, the urinary tract complications of the study group were significantly reduced (51.1% versus 23.0%, P < 0.01). There were a shorter surgical duration [(132 ± 20) min], less of the hemorrhage [(322 ± 100) ml] and blood transfusion [(154 ± 79) ml] in the study group than those in the control group (all P < 0.05). While, there was no significant difference at the survival rates of 5 years between the two groups (87.8% versus 88.6%, P = 0.793). CONCLUSION: The modified Piver class III hysterectomy is effective and applicable for patients with cervical cancer.

[Study on purification of polysaccharides in root of Salvia miltiorrhiza by macroporous adsorption resin and ion-exchange resin methods].

OBJECTIVE: To study the purification and isolation of polysaccharides from Salvia miltiorrhiza. METHODS: The root was extracted by water purified preliminarily by alcohol precipitation, and then four different types macroporous adsorption resin and one ion-exchange resin were comparatively investigated in the purification and isolation of Salvia polysaccharides. RESULTS: The total polysaccharides of crude extracts was 40.35%, and protein content amounted to 8.96%. Compared with the traditional methods, AB-8, DB-301 type of resin used in purification of polysaccharides could simplify the working process and obtain better effect. Then the obtained crude polysaccharides through AB-8 resin were purified by ion-exchange resin DEAE-52. Three portions of powder were obtained through lyophilization and named as SMP1, SMP2, SMP3. CONCLUSION: Purification of Salvia polysaccharides can be conducted by adoping AB-8, DB-301 type of resin and DEAE-52 ion-exchange resin.

Prevalence of single and multiple human papillomavirus types in cervical cancer and precursor lesions in Hubei, China.

OBJECTIVE: The objective of this study was to establish the prevalence and type distribution of human papillomavirus (HPV) in cervical cancer and cervical intraepithelial neoplasia (CIN) in Hubei, China. METHODS: A total of 112 patients with cervical cancer and 60 CIN II-III samples were obtained from women undergoing biopsy or surgery. HPV and typing were examined by the polymerase chain reaction (PCR) and sequencing. RESULTS: HPV DNA was detected in 105 patients with cervical cancer (93.75%), HPV 16 being detected in 91 (81.25%) cases, and HPV 58 in 7 (6.25%) cases. HPV DNA was detected in 50 patients with CIN II-III (83.33%), HPV 16 being detected in 37 (61.67%) cases, HPV 58 in 5 cases (8.33%). HPV 18 was not common in this study. About 11% cervical cancer and 8.33% CIN II-III specimens exhibited multiple infections (p = 0.79). CONCLUSION: The high prevalence of HPV 16 in Hubei, China, deserves attention as it has important implications for the usefulness of vaccine and the choice of diagnostic methods.

Class II radical hysterectomy in low-risk IB squamous cell carcinoma of cervix: a safe and effective option.

UNLABELLED: The aim of this study was to determine the outcome of class II radical hysterectomy for the treatment of a subset of patients with early cervical cancer. METHOD: From September 1995 to September 2003, a total of 480 patients whose conditions were diagnosed with squamous carcinoma of the cervix with a tumor size of no greater than 2 cm and a pathological grade 1 to 2 was enrolled in a cohort study to compare class II and class III radical hysterectomy, with 240 patients in each group. Disease-free survival, overall survival, pattern of recurrences, and morbidity were the end points of observation for this study. RESULTS: The class II surgery group had 100.0% overall and 98.33% disease-free actuarial 5-year survival rate, whereas the class III surgery group had 100.0% overall and 97.92% disease-free actuarial 5-year survival rate (P = 0.736). Recurrence rate (2.92% in class II vs 2.50% in class III) was not significantly different in the 2 groups (P = 0.779). The operating time, postoperative length of hospital stay, and estimated blood loss at surgery were significantly lower in the group of patients who underwent class II hysterectomy (P = 0.0001, P = 0.0001, and P = 0.001, respectively). The postoperative complications were also significantly lower in patients who received class II hysterectomy. CONCLUSIONS: In treating a subset of patients with tumor size no greater than 2 cm and grade 1 to 2 squamous cell cancer, class II and class III radical hysterectomy are equally effective, but the former has far less complications than the latter.

Combining differential expression and differential coexpression analysis identifies optimal gene and gene set in cervical cancer.

OBJECTIVE: The objective of this study is to investigate the optimal gene and functional-related gene set in cervical cancer through combing the differential expression (DE) and differential coexpression (DC) analysis. MATERIALS AND METHODS: To achieve this, we first measured expression data of cervical cancer by incorporating DE and DC effects utilizing absolute t-value in t-statistic and Z-test, respectively. Then, we selected the optimal threshold pair to determine both high DE and high DC (HDE_HDC) partition on the basis of Chi-square maximization, and the best threshold pair divided all genes into four parts, including HDE_HDC, high DE and low DC (HDE_LDC), low DE and high DC (LDE_HDC), and low DE and low DC (LDE_LDC). Using the known functional gene sets, functional relevance of partition genes was explored to determine the best-associated gene set based on the functional information (FI) conception. RESULTS: Under the optimal threshold pair of 3.629 and 1.108 for DE and DC, respectively genes were divided into four partitions: HDE_HDC (311 genes), HDE_LDC (2072 genes), LDE_HDC (seventy genes), and LDE_LDC (1623 genes). Meanwhile, the gene set epidermis development was the best-associated gene set with the largest △G* = 10.496. Among the genes of epidermis development, zinc finger protein 135 (ZNF135) attained highest minimum FI gain of 41.226. CONCLUSION: The combination of DE and DC analysis showed higher mean FI relative to individual DE and DC analyses. We successfully exhibited the optimal gene set epidermis development and gene ZNF135, which might be crucial for the prevention and treatment of cervical cancer.

[Mechanism of Platycarya strobilacea Sieb. et Zucc extract-induced methuosis in human nasopharyngeal carcinoma CNE1 and CNE2 cells].

OBJECTIVE: To study the effect of Platycarya strobilacea Sieb. et Zucc (PSZ) extract on methuosis of human nasopharyngeal carcinoma CNE1 and CNE2 cells and explore the underlying mechanism. METHODS: CNE1 and CNE2 cells were treated with 1 mg/mL PSZ extract and the expressions of Rac1 mRNA and Rac1 protein were detected using RT-qPCR and Western blotting, respectively. Results CNE1 and CNE2 cells showed obvious morphological changes typical of methuosis following treatment with PSZ extract characterized by cell merging, accumulation of large cytoplasmic vacuoles, and membrane rupture without obvious changes in the nuclei. PSZ treatment resulted in up-regulated Rac1 mRNA and Rac1 protein expressions in the cells. Application of EHT 1864 obviously blocked the effect of PSZ extract in inducing methuosis in CNE1 and CNE2 cells. CONCLUSION: PSZ extract can induce methuosis in CNE1 and CNE2 cells by inducing the overexpression of Rac1.

[Inhibiting effects of root of Mallotus apelta on duck hepatitis B virus].

OBJECTIVE: To evaluate the inhibiting effects of the root of Mallotus apelta (Lour.) Muell.-Arg. on duck hepatitis B virus (D-HBV) in vivo. METHODS: Forty nestling ducks with congenitally infection of D-HBV detected by PCR were randomly divided into five groups: untreated group, lamivudine-treated group, and high-, medium- and low-dose root of Mallotus apelta-treated groups. The ducks in the lamivudine-treated group were fed lamivudine with a dose of 50 mg/kg once. Ducks in the three-dose Mallotus apelta-treated groups were treated with different doses of decoction of this herbal medicine for 21 days respectively. The serum content of D-HBV DNA was determined by quantitative real-time PCR technique before and 7 days after the treatment, and on the 7th, 14th and 21st day of the treatment. Liver biopsy was also executed before and after the treatment to observe the histopathological changes. RESULTS: Lamivudine showed a rapid inhibiting effect on D-HBV DNA, but this effect didn't last long, and the serum level of D-HBV DNA increased again after treatment. The serum level of D-HBV DNA dropped markedly in the high- and medium-dose Mallotus apelta-treated groups on the 14th and 21st day. Low-dose Mallotus apelta revealed no obvious inhibiting effect on D-HBV. After treatment, the inhibiting effect in the root of Mallotus apelta-treated group continued as compared with that in the untreated group. The histopathological changes of liver tissues showed that the inflammation in the high-dose root of Mallotus apelta-treated group was weakened as compared with that in the lamivudine-treated group. CONCLUSION: The root of Mallotus apelta has therapeutic effect on D-HBV. It can restrain the duplication of D-HBV in vivo. Although this effect is weaker than that of lamivudine, it continues longer. Thus this herbal medicine is an effective, safe and economical drug for hepatitis B.