pRb Expression Research Articles

Values of ultrasound elastography and progesterone receptor proteins for diagnosis and prognostic evaluation of uterine fibroid.

We aimed to study the values of ultrasound elastography (UE) and progesterone receptor (PR) proteins for the diagnosis and prognostic evaluation of uterine fibroid (UF). A total of 200 UF patients treated from January 2020 to June 2023 were selected as a UF group, and another 100 healthy women as a healthy group. Routine ultrasound parameters uterine artery pulsatility index (PI), resistance index (RI), and UE parameter strain ratio (SR) were obtained. The relative protein expressions of PRA and PRB in the peripheral blood were detected by Western blotting. The differences in these parameters and relative protein expressions of PRA and PRB were compared. The UF patients were divided into a cure group (n = 159) and a recurrence group (n = 41) according to their prognosis. The protein expressions of PRA and PRB in the UF group were higher than those in the healthy group (p < 0.05). In the recurrence group, PI and RI were lower, while SR and the protein expressions of PRA and PRB were higher than those in the cure group (p < 0.05). Age at menarche < 13 years old, intramural fibroid, PI, RI, SR, PRA, and PRB were risk factors for recurrence in UF patients (p < 0.05). The efficiency of combination of ultrasound and UE parameters, PRA and PRB for the diagnosis and prognostic evaluation of UF was significantly higher than that of any single indicator ( p < 0.05). Ultrasound and UE parameters combined with PR proteins have high efficiency for the diagnosis and prognostic evaluation of UF.

Exploring the Role of MicroRNAs in Progesterone and Estrogen Receptor Expression in Endometriosis.

Background/Objectives: Patients with endometriosis still respond poorly to progestins due to progesterone resistance associated with microRNAs (miRNAs). The aim of this study was to investigate the expression of selected miRNAs, estrogen receptor (ER)α, ERβ, progesterone receptor (PR)-A and PR-B and to determine the target genes of upregulated miRNAs in endometriosis. Methods: In this study, 18 controls, 18 eutopic and 18 ectopic samples were analysed. Profiling and validation of miRNAs associated with functions of endometriosis were performed using next-generation sequencing (NGS) and qRT-PCR. At the same time, the expression of ERα, ERβ, PR-A and PR-B was also determined using qRT-PCR. Target prediction was also performed for miR-199a-3p, miR-1-3p and miR-125b-5p using StarBase. Results: In this study, NGS identified seven significantly differentially expressed miRNAs, of which six miRNAs related to the role of endometriosis were selected for validation by qRT-PCR. The expression of miR-199a-3p, miR-1-3p, miR-146a-5p and miR-125b-5p was upregulated in the ectopic group compared to the eutopic group. Meanwhile, ERα and ERβ were significantly differentially expressed in endometriosis compared to the control group. However, the expressions of PR-A and PR-B showed no significant differences between the groups. The predicted target genes for miR-199a-3p, miR-1-3p and miR-125b-5p are SCD, TAOK1, DDIT4, LASP1, CDK6, TAGLN2, G6PD and ELOVL6. Conclusions: Our findings demonstrated that the expressions of ERα and ERβ might be regulated by miRNAs contributing to progesterone resistance, whereas the binding of miRNAs to target genes could also contribute to the pathogenesis of endometriosis. Therefore, miRNAs could be used as potential biomarkers and for targeted therapy in patients with endometriosis.

Impact of HDAC6-mediated progesterone receptor expression on the response of breast cancer cells to hormonal therapy

Modulation of estrogen receptor (ER) and progesterone receptor (PR) expression, as well as their emerging functional crosstalk, remains a potential approach for enhancing the response to hormonal therapy in breast cancer. Aberrant epigenetic alterations induced by histone deacetylases (HDACs) were massively implicated in dysregulating the function of hormone receptors in breast cancer. Although much is known about the regulation of ER signaling by HDAC, the precise role of HDAC in modulating the expression of PR and its impact on the outcomes of hormonal therapy is poorly defined. Here, we demonstrate the involvement of HDAC6 in regulating PR expression in breast cancer cells. The correlation between HDAC6 and hormone receptors was investigated in patients’ tissues by immunohistochemistry (n = 80) and publicly available data (n = 3260) from breast cancer patients. We explored the effect of modulating the expression of HDAC6 as well as its catalytic inhibition on the level of hormone receptors by a variety of molecular analyses, including Western blot, immunofluorescence, Real-time PCR, RNA-seq analysis and chromatin immunoprecipitation. Based on our in-silico and immunohistochemistry analyses, HDAC6 levels were negatively correlated with PR status in breast cancer tissues. The downregulation of HDAC6 enhanced the expression of PR-B in hormone receptor-positive and triple-negative breast cancer (TNBC) cells. The selective targeting of HDAC6 by tubacin resulted in the enrichment of the H3K9 acetylation mark at the PGR-B gene promoter region and enhanced the expression of PR-B. Additionally, transcriptomic analysis of tubacin-treated cells revealed enhanced activity of acetyltransferase and growth factor signaling pathways, along with the enrichment of transcription factors involved in the transcriptional activity of ER, underscoring the crucial role of HDAC6 in regulating hormone receptors. Notably, the addition of HDAC6 inhibitor potentiated the effects of anti-ER and anti-PR drugs mainly in TNBC cells. Together, these data highlight the role of HDAC6 in regulating PR expression and provide a promising therapeutic approach for boosting breast cancer sensitivity to hormonal therapy.

Expression of miR-34a, RASSF1A and E-cadherin in relation to PRB in endometrioid carcinoma and its precursor.

The current study aims to evaluate the levels of miR-34a, RASSF1A, and E-cadherin in relation to the levels of isoform B of progesterone receptor (PRB) in endometrioid carcinoma (EC) and atypical hyperplasia (AEH) and their association with clinicopathological parameters. 105 cases (35 EC, 35 AEH, and 35 control) were involved in this study. Cases of AEH received treatment, and other samples were obtained after 6 months to assess the response. E-cadherin and PRB were assessed by immunohistochemistry (IHC), RASSFA methylation by MSP-PCR, and its serum level by ELISA and miR-34a via quantitative PCR. The expressions of miR-34a, RASSF1A, E-cadherin, and PRB differ among the studied groups; all were higher in normal compared with AEH and EC, with a statistically significant difference. The higher PRB expression and decreased miR-34a and RASSF1A expression were associated with resistance to hormonal therapy in AEH. High PRB in EC is associated with lower RASSFA1, E-cadherin, and miR-34a. Decreased expressions of RASSF1A, miR-34a, and E-cadherin had a significant connection to advanced stages. Expression of PRB and miR-34a and serum levels of RASSF1A predict response to treatment in cases of AEH. High PRB and low E-cadherin expression are associated with progressive disease in EC.

How Progesterone Receptor Expression Impacts Platinum Sensitivity in Ovarian Clear Cell Carcinoma: Insights from Clinical and Experimental Perspectives.

Ovarian clear cell carcinoma (OCCC) is often considered a relatively platinum-resistant malignancy. The aim of this study was to explore the influence of progesterone receptor (PR) expression levels on platinum sensitivity and survival outcomes in people with OCCC. A retrospective analysis was conducted with 80 people with OCCC who underwent surgery followed by adjuvant chemotherapy. PR expression was assessed via immunohistochemical (IHC) staining and quantified using the H score. The platinum sensitivity and survival outcomes of patients with weak and strong PR expression were compared. Additionally, cisplatin viability and migration experiments were conducted with OCCC cell lines (ES-2 and TOV-21G) with varying PR isoform expressions. Among the 80 patients, 62 were classified as having platinum-sensitive disease, while 18 had platinum-resistant disease. The mean total PR H- score of platinum-sensitive tumors was significantly higher than that of platinum-resistant tumors (p = 0.002). Although no significant differences in progression-free and overall survival were observed between patients with high and low PR expression, those with high PR expression tended to have longer survival. While PR protein was only weakly detectable in ES-2 and TOV-21G cells, a transfection of the PR-A or PR-B gene resulted in a strong expression of PR-A or PR-B, which led to significantly reduced proliferation and migration in ES-2 and TOV-21G cells. Furthermore, overexpression of PR-A or PR-B enhanced cisplatin cytotoxicity in these cell lines. In conclusion, strong PR expression was associated with improved platinum sensitivity and survival outcomes, consistent with our experimental findings. The potential of PR as a tumor sensitizer to cisplatin in OCCC warrants further investigation.

STEM-06. THE ROLE OF SHH SIGNALING PATHWAY IN RETINOBLASTOMA INITIATION AND PROGRESSION

Abstract BACKGROUND Retinoblastoma is a rare childhood cancer of the retina that shows the biallelic loss of RB1 in nearly 95% of cases. It was reported that SHH pathway proteins, such as SHH, GLI1, and GLI2, are aberrantly high in human retinoblastoma, and high GLI2 expression is associated with aggressive clinicopathological features. Thus, we assessed whether activation of SHH pathway by overexpression of Gli2 or SMO induces the initiation of retinoblastoma. METHODS We generated a Cre-activated, Doxycycline (Dox)-controlled transgenic model to induce SMO or Gli2 expression in developing retina. In this transgenic mouse, expression of Smo or Gli2A is under the control of TRE, which permits temporal and spatial expression of Smo or Gli2A by administering/withdrawing doxycycline (DOX). RESULTS We fed the triple transgenic mice (Chx10-Cre/R26-LSL-rtTA/tetO-Smo or Chx10-Cre/R26-LSL-rtTA/tetO-Gli2A starting from E0 or P5. Our studies demonstrated that control littermates (Cre-) did not show any abnormalities, while mice with triple transgenes developed tumors in the bilateral eyes with 100% morbidity. The animals showed symptoms of leukocoria at P0-P3 or P25-p30 if the oncogenes were initiated at E0 or P5 respectively. The tumor cells were highly proliferative and expressed retina progenitor cell specific marker of Sox2, showing aberrant expression of pRB, CDK4/6, and CCND1. CONCLUSIONS Our results demonstrate that overexpressing Smo or Gli2 in Chx10+ cells induce rapid tumor formation in mouse retina. In future study, we plan to (i) investigate the impact of Shh pathway activation in RPCs on RB tumorigenesis within the context of Rb1 loss; (ii) define the molecular mechanisms underlying tumor initiation and progression; and (iii) evaluate whether targeting SHH pathway prevents or delays tumor initiation and progression using our Gli2-driven mouse model and patient-derived xenografts.

Effect of Chitosan on Synovial Membrane Derived Cells and Anterior Cruciate Ligament Fibroblasts.

Previously, chitosan reduces the senescence-related phenotypes in human foreskin fibroblasts through the transforming growth factor beta (TGF-β) pathway, and enhances the proliferation and migration capabilities of these cells are demonstrated. In this study, we examined whether the senescence-delaying effect of chitosan could be applied to primary knee-related fibroblasts, such as human synovial membrane derived cells (SCs) and anterior cruciate ligament fibroblasts (ACLs). These two types of cells were obtained from donors who needed ACL reconstruction or knee replacement. We found that chitosan treatment effectively reduced aging-associated β-galactosidase (SA-β-gal)-positive cells, downregulated the expression of senescence-related proteins pRB and p53, and enhanced the 5-bromo-2'-deoxyuridine (BrdU) incorporation ability of SCs and ACLs. Moreover, chitosan could make SCs secret more glycosaminoglycans (GAGs) and produce type I collagen. The ability of ACLs to close the wound was also enhanced, and the TGF-β and alpha smooth muscle actin (αSMA) protein expression decreased after chitosan treatment. In summary, chitosan not only delayed the senescence but also enhanced the functions of SCs and ACLs, which is beneficial to the application of chitosan in cell expansion in vitro and cell therapy.

P16 overexpression identifies oncogenic high-risk HPV infection in non-oropharyngeal squamous cell carcinoma of the head and neck.

Human papillomavirus (HPV) is an increasing risk factor for cancer. HPV-associated oropharyngeal squamous cell carcinoma (OPSCC) is associated with a favorable outcome. Blockstaining for p16 is a surrogate marker for HPV+ OPSCC. In oral and laryngeal squamous cell carcinoma (OSCC/LSCC), the relevance of p16 immunohistochemistry, alone or in combination with other cell cycle-related proteins, to identify HPV-driven non-OPSCC is less well understood. We stained for p16, pRb, cyclin D1, and p53 in 327 HNSCC. In 310 OPSCC, HPV-status was assessed by HPV DNA PCR. In 119 non-OPSCC, RNA in situ hybridization was additionally performed. HPV-status was correlated with staining patterns, p53 and clinical data. The OPSCC showed blockstaining for p16 in 36%, 8% were equivocal. Of these, HPV-testing was performed in 57%, and 53% were positive for HPV DNA. HPV-association correlated with absence of pRb and cyclin D1 and favorable outcome. In non-OPSCC, 18% showed p16-blockstaining, and 13% showed E6/E7 RNA. Six of seven HPV+ OSCC and 8/8 LSCC lost pRb and cyclin D1. Compared to HPV-negative counterparts, patients with HPV+ cancers had lower rates of alcohol consumption and keratinizing morphology. HPV-positive OSCC had a longer overall survival (p < 0.05). HPV subtype 16 was the most common. We conclude that HPV-positive non-OPSCC are associated with p16 overexpression and low levels of pRb and cyclin D1. High expression of pRb and cyclin D1 indicates HPV-negativity.

Abstract 5166: A multiplexed immunofluorescence assay to assess Rb and phospho-Rb as predictive biomarkers for CDK4/6 inhibitors in HR+/HER2- breast cancer

Abstract Introduction: Cyclin-dependent kinases 4/6 inhibitors (CDK4/6i) are used as the first-line treatment of advanced/metastatic or high-risk HR+/HER2- breast cancer (BC) that make up about 60-70% of all cases. However, nearly 50% of patients exhibit drug resistance. Therefore, biomarkers that predict CDK4/6i response are needed to spare patients from toxicities and high costs. Resistance to CDK4/6i [palbociclib, ribociclib, and abemaciclib] is associated with the aberrant or loss of Retinoblastoma (Rb). A decline in phospho-Rb (pRb) levels on therapy is also associated with CDK4/6i response. We aimed to develop a multiplex immunofluorescence (IF) assay to assess Rb and pRb levels that can be used on circulating tumor cells (CTCs) to predict tumor response to CDK4/6i. Here, we report the selection of internal controls for Rb and pRb, assay repeatability and reproducibility, as well as compatibility of the CTC isolation protocol with the assay. Methods: Rb and pRb expression was evaluated by western blotting (WB) and IF in parental (P), estrogen deprivation-resistant (EDR), palbociclib-resistant (PalboR), and EDR/PalboR derivatives of two HR+/HER2- cell lines (MCF7 and T47D), Rb1 KO cells of MCF7 and T47D, as well as triple-negative cell lines, BT549 and MDA-MB-468. IF-stained cells were imaged using Leica STED SP8 confocal microscope and Zeiss Axioscan 7. The concordance between IF and WB results was assessed using a Bland-Altman plot. Selectivity and specificity of the assay as well as repeatability and reproducibility between investigators were also assessed. Blood from healthy subjects was used to test the compatibility of the ScreenCell® filtration system to isolate CTC with the IF assay. Results: Our initial approach utilized indirect IF staining for Rb and pRb using the same primary antibodies as WB. On the Bland-Altman plot, most data points were relatively close to the bias line, suggesting that the difference between the two methods was acceptable. The analytical range for mean Rb and pRb staining intensity was 0.744 - 46.779 and 1.001 - 52.919, respectively. Based on WB and IF data, we nominated T47D PalboR and MDA-MB-468 cells as negative controls for Rb and pRb expression. The selectivity and specificity were 100% and 70%, respectively, for the Rb expression and 99% and 61% for pRb, respectively. The IF assay was repeatable and reproducible between two investigators. The ScreenCell® CTC isolation method was not compatible with the assay, as Rb and pRb expression was either not detected or limited when processed using FC2 or PBTFC buffer, irrespective of the antigen retrieval. Conclusion: We have selected internal cell line controls for Rb and pRb and are in the process of optimizing signal-to-noise ratio and specificity using conjugated antibodies. We are also testing the compatibility of other CTC isolation methods with the IF assay. Citation Format: Mantasha Tabassum, Shivaani Suresh Kanna, Wangjia Cao, Mothaffar Rimawi, George E Miles, Meghana V Trivedi. A multiplexed immunofluorescence assay to assess Rb and phospho-Rb as predictive biomarkers for CDK4/6 inhibitors in HR+/HER2- breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5166.

Assessment of Differential Expression of Progesterone Receptors A &amp; B in Endometriosis Undergoing IVF Treatment: A Personalized Approach for Better IVF Success

Objective: Estrogen and Progesterone hormones play a pivotal role in the pathogenesis of Endometriosis. In the present study, relative quantification of PR-A and PR-B expression in eutopic endometrial tissue and endometriotic implants was done. By examining their expression profiles, we aim to gain deeper insights into the molecular mechanisms that can influence IVF success or failure in endometriotic patients. Our study also observed certain ART outcomes in both endometriosis and control groups, to evaluate the IVF success rate. Methods: This study was conducted at MHRT, a tertiary care center, and referral centers from other hospitals. The research encompassed an examination of 125 cases of infertility spanning from January 2019 to January 2023. Finally, biopsy samples were collected from 60 patients with endometriosis during laparoscopic procedures, while control biopsy samples were gathered from 18 patients who exhibited no signs of endometriosis lesions during the same laparoscopic procedures. The biopsy samples were then sent for Progesterone assay and later evaluated for ART outcomes. Results: It was observed from the results of our study that there was a significant downregulation of PR-A in stage III, and IV compared to Stage I and II. However, there was no significant change in PR-B expression in grades I and II, III and IV. Our study also observed certain ART outcomes in both endometriosis and control groups, revealing that women with endometriosis have lower chances of achieving pregnancy than women with other causes of infertility (95% CI, 22/60 vs. 12/18, p-value = 0.024). Conclusion: Our study results shed light on the complex role of progesterone isoforms in endometriosis. Progesterone receptor-A significant downregulation in severe cases challenges existing paradigms and opens new avenues for research.

Investigating the Potential Role of IKZF3 in HPV-Associated Carcinogenesis

HPVs cause approximately 5% of all human cancers. They encode two viral transforming proteins, E6 and E7, that are consistently expressed in these cancers. The HPV E6 and E7 proteins contribute to carcinogenesis by binding and functionally compromising multiple cellular regulatory proteins, most prominently the p53 and retinoblastoma (pRB) tumor suppressors, respectively. To discover additional cellular regulatory circuits that are dysregulated by E6 and E7 expression, we performed RNA sequencing analyses of HPV16 E6 and E7 expressing primary human genital epithelial cells. These experiments revealed that the Ikaros Zinc Finger 3 (IKZF3) transcription factor is highly upregulated in HPV16 E6/E7 expressing keratinocytes as compared to control keratinocytes. IKZF3 plays a key role in lymphocyte development, and when over-expressed or mutated, contributes to hematopoietic malignancies. IKZF3 is expressed at a very low level in normal epithelial cells, but the expression is upregulated in solid tumors, including invasive breast, cervical, and lung cancers. IKZF3 expression in these tumors causes upregulation of lymphocyte-specific genes, conferring lymphocyte-like behavior referred to as "lymphocyte mimicry," which presumably enables cancer cell survival in the bloodstream, thus potentially contributing to cancer metastasis. There is an FDA-approved drug, lenalidomide, that targets IKZF3 for degradation. Hence, we set out to determine whether IKZF3 might contribute to cervical carcinogenesis. We treated HPV16-positive SiHa and CaSki cervical cancer cells with 10 uM of lenalidomide for 12 hours. Cells were treated with equal amounts of DMSO as a negative control. Then, IKZF3 and E7 mRNA expression were determined using qRT-PCR after 12 hours of treatment. Gene expression was analyzed relative to GAPDH, and the results were analyzed using 2-way ANOVAs with Dunnett's correction for multiple comparisons. Western Blot experiments were performed to examine IKZF3, pRB, E7, and p53 (to indirectly assess E6) protein expression levels after 12 hours of lenalidomide treatment. Actin protein was used as a loading control. Each of these experiments were performed 3 times, qRT-PCR experiments were each performed in triplicate, and the results were graphed using a scientific 2-D graphing and statistics software. Although Western Blot showed that IKZF3 protein levels were significantly decreased by lenalidomide treatment, there was no change in pRB, E7, and p53 protein expression upon IKZF3 depletion. Similarly, there was no decrease in E7 mRNA expression. We showed by western blotting that targeting IKZF3 for proteasome-mediated degradation with lenalidomide effectively decreased the steady-state levels of IKZF3. However, we did not consistently observe an associated decrease in HPV gene expression. We are currently analyzing the transcriptome changes that IKZF3 depletion causes in cervical carcinoma cells to determine whether this may affect anoikis resistance.

Association between Human Papilloma Virus (HPV) genotype and protein of retinoblastoma expression in cervical cancer

Link of Video Abstract: https://youtu.be/5Q9QmV4Qmyg Background: Regarding prevalence among females worldwide, cervical cancer ranks fourth and has a high fatality rate. Cervical cancer growth is correlated with high-risk human papillomavirus (HPV) infection. Retinoblastoma protein (pRb) is a protein that interacts with E6/E7 oncoproteins to regulate cell proliferation, differentiation, and death. Mutations on the E6/E7 protein oncogenes of high-risk HPV can disrupt this relationship. This investigation aims to establish the association between pRb expression and the HPV genotype. Methods: This observational cross-sectional study examined 43 patients diagnosed with cervical cancer at Wahidin Sudirohusodo Hospital and its network. Samples were taken using consecutive random sampling based on established criteria. HPV genotype was examined using the polymerase chain reaction (PCR) method, while pRB expression was assessed by immunohistochemical examination. The relationship between the two variables was assessed using the Chi-Square test. Results: There were 5 (11.6%) patients with HPV type 16, 14 (32.6%) with HPV type 18, 12 (27.9%) with other types of HPV and 12 (27.9%) were negative for HPV. Examination of pRb expression showed that 33 (76.7%) samples had +2 expression, 7 (16.3%) had +1 expression, and 3 (7.0%) samples had no pRb expression. The pRb expression and HPV type were not significantly correlated in this study (p = 0.410). However, pRb expression and cervical cancer clinical stage were shown to be significantly correlated (p = 0.007). Conclusion: pRb expression is more prevalent when a malignancy is more advanced. In this investigation, no association between HPV genotype and pRb expression was discovered, despite oncogene mutations being involved in the regulation mechanism of cell proliferation, differentiation, and apoptosis.

Effects of high-risk human papillomavirus infection on P53, pRb, and survivin in lung adenocarcinoma-a retrospective study.

To observe the effects of high-risk human papillomavirus (HR-HPV) infection on P53, pRb, and survivin in lung adenocarcinoma (LUAD). The cancerous and cancer-adjacent tissues of 102 patients with LUAD from January 2020 to April 2022 were selected for the study. HR-HPV infection was detected by flow fluorescence method, and P53, pRb, and survivin protein expression was detected by immunohistochemical staining method. Statistical analysis was performed to determine the differences in the HR-HPV infection and the expression of P53, pRb, and survivin proteins between LUAD tissues and cancer-adjacent tissues; the correlation between HR-HPV infection and P53, pRb, and survivin protein expression in cancer tissues; and the correlation between HR-HPV infection and clinicopathological features of LUAD. The infection rate of HR-HPV was higher in the LUAD tissues (28.43%) than in cancer-adjacent tissues (7.84%), and the difference was statistically significant (P<0.05). The positive rates of P53 and survivin protein were higher in the LUAD group (33.33% and 67.16%, respectively) than in the cancer-adjacent group (3.92% and 11.73%, respectively), and the difference was statistically significant (P<0.05). The positive rate of pRb protein was lower in the LUAD group (58.82%) than in the cancer-adjacent group (92.14%), and the difference was statistically significant (P<0.05). The positive rates of P53 and survivin proteins were significantly higher in the HR-HPV LUAD group (58.62% and 86.21%, respectively) than in the non-HR-HPV LUAD group (41.38% and 67.12%, respectively), and the difference was statistically significant (P<0.05). The expression rate of pRb protein was significantly lower in the HR-HPV LUAD group (37.93%) than in the non-HR-HPV LUAD group (67.12%), and the difference was statistically significant (P<0.05). The expression of p53 and survivin protein was positively correlated with HR-HPV infection (r=0.338 and 0.444, P<0.05), whereas the expression of pRb protein was negatively correlated with HR-HPV infection (r=-0.268, P<0.05). HR-HPV infection was not associated with gender, age, and smoking in patients with LUAD (P>0.05). HR-HPV infection was associated with lymph node metastasis and clinical stage of LUAD (P<0.05). HR-HPV infection was associated with lymph node metastasis and clinical stage of LUAD, which may be achieved by up-regulating p53 and survivin protein expression and down-regulating pRb protein expression.

P16INK4a and pRb expression in laryngeal squamous cell carcinoma with and without infection by EBV or different genotypes of HPV: a retrospective study

BackgroundLaryngeal squamous cell carcinoma (LSCC) represents one of the principal tumors of the head and neck. Human papillomavirus (HPV) and Epstein–Barr virus (EBV) are considered risk factors for the development and the clinical prognosis of LSCC. High levels of p16INK4a are suggested as a surrogate marker of HPV or EBV infection in some head and neck tumors but in LSCC is still controversial. Furthermore, pRb expression may be considered an additional biomarker but it has not been clearly defined. This work aimed to compare the expression of pRb and p16INK4a as possible biomarkers in tumor tissues with and without infection by EBV or different genotypes of HPV from patients with LSCC.MethodsTumor samples from 103 patients with LSCC were previously investigated for the presence and genotypes of HPV using the INNO-LiPA line probe assay and for the infection of EBV by qPCR. p16 INK4a and pRb expression was assessed by immunohistochemistry.ResultsOf the 103 tumor samples, expression of p16INK4a was positive in 55 (53.4%) and of this, 32 (56.1%) were positive for HPV whereas 11 (39.3%) were EBV positive but both without a significantly difference (p > 0.05). pRb expression was positive in 78 (75.7%) and a higher frequency of this expression was observed in HPV negative samples (87.0%) (p = 0.021) and in high-risk HPV negative samples (85.2%) (p = 0.010). No difference was observed when comparing pRb expression and EBV infection status (p > 0.05).ConclusionOur results support the suggestion that p16INK4a is not a reliable surrogate marker for identifying HPV or EBV infection in LSCC. On the other hand, most of our samples had pRb expression, which was more frequent in tumors without HPV, suggesting that pRb could indicate HPV negativity. However, more studies with a larger number of cases are required, including controls without LSCC and evaluating other molecular markers to determine the real role of p16INK4a and pRb in LSCC.

Prognosis and survival study in patients with gastric adenocarcinoma and its relationship with pRb expression alteration: A retrospective IHC-based study.

Among cancers, gastric cancer has the fifth highest incidence worldwide and is the third most common mortality factor, which may have been due to inadequate knowledge of its molecular pathogenesis. The retinoblastoma gene (RB1), a tumor suppressor gene, may have a role in gastric cancer. This research aims to assess Rb expression as a prognostic marker to obtain more insight regarding gastric cancer. This retrospective analytical study was done on 61 patients (45 males and 16 females) with gastric adenocarcinoma admitted from 2010 to 2012 in Shahid Sadoughi and Mortaz hospitals, Yazd, Iran. Demographic data, including age, gender, clinical signs and symptoms, and pathology reports, were retrieved from patients' hospital folders. Then, the altered Retinoblastoma gene expression was evaluated by immunohistochemistry studies. Acquired data were analyzed by SPSS software v.16. p < 0.05 was statistically considered meaningful. In this study, the ratio of men to women was higher (2.81:1), and the mean age of patients was 62.44 years. About 90.2% of patients died during the study. There was no meaningful relationship between the presence of pRb, the intensity of staining, the percentage of staining with patients' age, gender, tumor grading, and survival rate (p > 0.05). There was only a meaningful relationship between the grade of tumors and survival rate (p = 0.039). Altered pRB expression is not common in gastric cancer and does not impact the survival and grading of tumors. Poorly differentiated tumors had an ominous outcome with the lowest survival time.

Formononetin Inhibits Progression of Endometriosis via Regulation of p27, pSTAT3, and Progesterone Receptor: In Vitro and In Vivo Studies.

Formononetin is one of the phytoestrogens that functions like a selective estrogen receptor modulator (SERM). In this study, we evaluated the effects of formononetin on endometriosis progression in vitro and in vivo. After pathological confirmation, 10 eutopic and ectopic endometria were collected from patients with endometriosis. Ten eutopic endometria samples were collected from patients who did not have endometriosis. To determine the cytotoxic dose and therapeutic dose of formononetin, the concentration of 70% of the cells that survived after formononetin administration was estimated using a Cell counting kit-8 (CCK 8) assay. Western blot analysis was used to determine the relative expression levels of BAX, p53, pAKT, ERK, pERK, p27, and pSTAT3 in the eutopic endometria without endometriosis, eutopic endometria with endometriosis, and ectopic endometria with endometriosis as the formononetin concentration was increased. We confirmed the effect of formononetin on apoptosis and migration in endometriosis using fluorescence-activated cell sorting (FACS) and wound healing assays, respectively. A mouse model of endometriosis was prepared using a non-surgical method, as previously described. The mice were intraperitoneally administered formononetin for four weeks after dividing them into control, low-dose formononetin (40 mg/kg/day) treatment, and high-dose (80 mg/kg/day) formononetin treatment groups. All the mice were euthanized after formononetin treatment. Endometriotic lesions were retrieved and confirmed using hematoxylin and eosin (H&E) staining. Immunohistochemical (IHC) staining of p27 was performed. We set the maximum concentration of formononetin administration to 80 μM through the CCK8 assay. Based on formononetin concentration, the expression levels of BAX, p53, pAKT, ERK, pERK, p27, and pSTAT3 proteins were measured using Western blot analysis (N = 4 per group). The expression level of pERK, p27, and pSTAT3 in eutopic endometrium with endometriosis tended to decrease with increasing formononetin concentration, and a significant decrease was noted at 80 μM. The expression of p27 in ectopic endometrium with endometriosis was also significantly decreased at 80 μM of formononetin. FACS analysis revealed that formononetin did not significantly affect apoptosis. In the wound healing assay, formononetin treatment revealed a more significant decrease in the proliferation of the eutopic endometrium in patients with endometriosis than in the eutopic endometrium without endometriosis. Relative expression of sex hormone receptors decreased with increasing formononetin doses. Although no significant differences were observed in the ER, PR-A, ERβ/ERα, and PR-B/PR-A, significant down-regulation of PR-B expression was noted after formononetin treatment at 80 μM. In the in vivo study, endometriotic lesions in the formononetin-treated group significantly decreased compared to those in the control group. The relative expression of p27 using IHC was highest in the control group and lowest in the high-dose formononetin treatment group. Formononetin treatment was shown to inhibit the proliferation of eutopic and ectopic endometria in patients with endometriosis through the regulation of p27, pSTAT3, and PR-B. In an endometriosis mouse model, formononetin treatment significantly reduced the number of endometriotic lesions with decreased p27 expression. The results of this study suggest that formononetin may be used as a non-hormonal treatment option for endometriosis.

P-321 increased expression of TGF-β1 contributes to the downregulation of progesterone receptor expression in the eutopic endometrium of infertile women with minimal/mild endometriosis

Abstract Study question Do immune cells regulate progesterone resistance and endometrial receptivity of eutopic endometrial stromal cells (ESCs) by transforming growth factor-β1 (TGF-β1)? Summary answer By activating TGF-β/Smad signaling in eutopic ESCs, elevated TGF-β1 from CD45+ immune cells could attenuate expression of progesterone receptor (PR), and further decrease endometrial receptivity. What is known already Endometriosis is a hormone-dependent disease related to impaired immunoregulation. We characterized the trascriptomic transformation of eutopic endometrium from patients with minimal/mild endometriosis and controls across the menstrual cycle. However, the regulatory mechanism of altered immune microenvironment on eutopic ESCs remains unclear. Study design, size, duration Single-cell RNA transcriptomes were profiled using 10x Genomics platform. Primary culture of eutopic ESCs was performed to explore the effects of TGF-β1 on the expression of Smad / PR, and the in vitro decidualization. Additionally, co-immunoprecipitation (Co-IP) was used to explore the direct interaction between Smad and PR. Participants/materials, setting, methods Endometrial tissue samples were obtained from twenty-four women who were laparoscopically confirmed minimal/mild endometriosis according to the revised American Fertility Society classification. Additionally, four patients who were laparoscopically endometriosis-free were enrolled as controls. All samples were collected in DMEM/F12 medium and processed in one of two ways, either for single-cell sequencing (n = 10) or primary cell culture (n = 14). Main results and the role of chance The results of single-cell RNA sequencing revealed that the percentage of CD45+ cells in eutopic endometrium was increase in both proliferative (26% vs 24.1%) and secretory (19.3% vs 8.3%) stages. Overexpression of TGF-β1 of CD45+ cells was observed in eutopic endometrium of endometriosis in both proliferative and secretory stages. We found attenuate expression of PRB (p = 0.026) and PRA (p = 0.678) after using TGF-β1 in eutopic ESCs by western blot. Similarly, qRT-PCR results showed that the mRNA level of PR (p＜0.001), PRB (p = 0.003) and HOXA10 (p＜0.001) decreased significantly after TGF-β1 treatment, but that increased (p＜0.01) after SB431542 treatment in the eutopic ESCs. Moreover, TGF-β1 has a negative effect on the in vitro decidualization of eutopic ESCs (p = 0.003). And the group with treatment of both TGF-β1 and SB435142 in eutopic ESCs showed significant decidual-like changes with increased prolactin level (p = 0.01). Co-IP showed no physical interaction between the PR and p-Smad3/Smad3 proteins. Limitations, reasons for caution This study focused on CD45+ immune cells and the cytokine, TGF-β1. Further in vivo and in vitro studies are needed to elucidate the specific types of immune cell and the mechanisms that behind endometrial receptivity decrease in endometriosis. Wider implications of the findings Our results demonstrate abnormal activation of CD45+ cells in eutopic endometrium with minimal/mild endometriosis. And overexpression of TGF-β1 was found by CD45+ cells. We found that TGF-β1 suppresses PR expression and decidualization in eutpoic ESCs. These results provide a novel insight into the mechanisms behind progesterone resistance in endometriosis. Trial registration number not applicable

HGG-08. COMBINATORIAL ACTIVITY OF CDK4/6-INHIBITORS AND TRAMETINIB IN PEDIATRIC HIGH-GRADE GLIOMA WITH BRAFV600E MUTATION AND HOMOZYGOUS CDKN2A DELETION

Abstract BRAFV600E mutations occur in 10-15% and homozygous CDKN2A deletions in approximately 40% of adolescent and pediatric high-grad glioma (HGG) and is associated with significantly decreased overall survival. Moreover, a subset of pHGG is defined by combined BRAFV600E mutation and concomitant CDKN2A homozygous deletion. Standard therapy has remained unchanged and consists of maximal safe resection and focal radiotherapy still resulting in poor overall survival. Therefore, new therapeutic approaches to increase patient survival are of utmost importance. Targeted therapy of BRAFV600E mutant HGG has emerged as effective treatment but remains challenging due to therapy resistance. CDK4/6 inhibitors represent a promising target in CDKN2A altered HGG. However, palbociclib demonstrated only low efficacy in HGG patients. Therefore, combination approaches may be more effective, and we investigated CDK4/6-inhibitors alone and in combination with trametinib in HGG cell models with BRAFV600E mutation and homozygous CDKN2A deletion. Efficacy of CDK4/6-inhibitor monotherapy and combinatorial approach with trametinib was assessed by short- and long-term viability assays in four patient-derived HGG cell models with homozygous CDKN2A deletion and BRAFV600E mutation. Furthermore, effects of CDK4/6 inhibitor therapy alone or in combination with trametinib on downstream signaling pathways (MAPK, PI3K) were analyzed with Western blots. Abemaciclib showed the highest activity in all cell models with IC50-values ranging from 0,5 – 2µM. Combined treatment approaches with trametinib showed synergistic effects across all cell models. Long-term viability assays revealed distinct sensitivity in the nanomolar range for CDK4/6-inhibitors and combined treatment with trametinib in all cell models. Exposure to abemaciclib and trametinib significantly decreased pRB, pERK, pS6, and pAKT protein expression levels when compared to monotherapy alone. Summarizing, combined treatment with CDK4/6-inhibitors and trametinib showed promising therapeutic effects on HGG models with homozygous CDKN2A deletion and BRAFV600E mutation. Currently, effects on cell cycle distribution and downstream molecular mechanisms are investigated to identify potential predictive biomarkers.

Prognostic and Clinicopathological Significance of the Loss of Expression of Retinoblastoma Protein (pRb) in Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aims to evaluate the scientific evidence on the implications of retinoblastoma protein (pRb) alterations in oral cancer, in order to determine its prognostic and clinicopathological significance. PubMed, Embase, Web of Science, and Scopus were searched for studies published before February 2022, with no restrictions by publication date or language. The quality of the studies using the Quality in Prognosis Studies tool (QUIPS tool). Meta-analysis was conducted to achieve the proposed objectives, as well as heterogeneity, subgroup, meta-regression, and small study-effects analyses. Twenty studies that met the inclusion criteria (2451 patients) were systematically reviewed and meta-analyzed. Our results were significant for the association between the loss of pRb expression and a better overall survival (HR = 0.79, 95%CI = 0.64–0.98, p = 0.03), whereas no significant results were found for disease-free survival or clinico-pathological parameters (T/N status, clinical stage, histological grade). In conclusion, our evidence-based results demonstrate that loss of pRb function is a factor associated with improved survival in patients with OSCC. Research lines that should be developed in the future are highlighted.

IL-2 rescues impaired T cell function upon loss of Itk via metabolic reprogramming

Abstract IL-2 inducible T cell kinase (Itk) is a critical component of T cell receptor (TCR) signaling required for activation of PLCg and downstream transcription factors, that regulate expression of effector molecules. Loss of Itk impairs T-cell activation by modulating the strength of TCR signal. Itk −/−mice have defects in T cell development with decreased proliferation and impaired differentiation to multiple CD4 T helper lineages. Most severe defects are seen in differentiation of Th9 cells, which produce the cytokine, IL-9. Under Th9 differentiation conditions, Itk −/−cells initially appear similar to WT cells but at 72hrs fail to sustain long-term expression of effector molecules. Th9 differentiation could be rescued by inclusion of IL-2. Itk −/−CD4 T cells show decreased mTORC1 signaling and do not maintain expression of IRF4, c-Myc, pRb and multiple nutrient transporters, including the Glucose transporter 1 (GLUT1), transferrin receptor (CD71), and amino acid co-transporter (CD98), all of which were rescued by IL-2. IL-2 is not required initially but can be added as late as 48hrs into culture. Using SCENITH—a flow cytometry-based technique that profiles metabolism—we found that WT differentiated Th9 cells were primarily glycolytic. In contrast, Itk −/−Th9 cells were less synthetic and more dependent on mitochondrial respiration. Inclusion of IL-2 in Itk −/−cultures rescued metabolic profiles, comparable to WT cells. Our results suggest that metabolic flexibility is central to dictating the functional/effector fate of CD4 T cells and that the Tec kinase Itk and IL-2-mediated pathways are required for maintenance of metabolic integrity, providing novel insight into mechanisms by which IL-2 can rescue T cell functional defects. This work was supported by the Intramural Research Program of NIAID, NIH.