Elevated Expression of Programmed Death-1 and Programmed Death Ligand-1 Negatively Regulates Immune Response against Cervical Cancer Cells

Transforming growth factor-β micro-environment mediated immune cell functions in cervical cancer

Propensity to develop cervical cancer (CC) in human papilloma virus (HPV) infected individual could potentially involve the impaired immune functioning. Several stages of HPV surveillance by immune cells in tumor micro-environment (TME) is regulated mainly by transforming growth factor-beta (TGF-β) and is crucial for the establishment of CC. The role of TGF-β in the initiation and progression of CC is very complex and involve different suppressor of mothers against decapentaplegic homolog (SMAD) dependent and SMAD independent signaling mechanism(s). This review summarizes the handling of HPV by immune cells such as T lymphocytes, B lymphocytes, natural killer cells (NK), dendritic cells (DC), monocytes, macrophages, myeloid derived suppressor cells (MDSC) and their regulation by TGF-β. The hijack mechanisms adapted by HPV to evade this surveillance process is discussed. Biomarkers indicating the stages of CC and immune checkpoints that can be targeted for improved outcome are included for immune-based theragnostics. This review also addresses the direct actions of TGF-β on CC cells and tumor/immune cell interactions. Therapies focused on targeting TGF-β using small molecule inhibitors, monoclonal antibodies and TGF-β chimeric antigen receptor (CAR)T cells are collated to understand the current strategies related to TGF-β in the management of CC.

The expression and significance of PD-L1 in condyloma acuminatum

BACKGROUND

It has been reported that programmed death-ligand 1 (PD-L1) is highly expressed in cells during viral infection, which helps the virus escape host immunity. However, the relationship between human papillomavirus (HPV) and PD-L1 in condyloma acuminatum and whether they participate in immunosuppression have not been reported. In this paper, we aimed to explore the expression and significance of PD-L1 in condyloma acuminatum.

METHODS

The expression of PD-L1 in the wart of condyloma acuminatum patients and the foreskin of healthy individuals was evaluated. Lentivirus transfection was used to introduce the HPV11-E7 gene into HaCaT cells to investigate whether HPV infection could affect the expression of PD-L1. The successfully constructed HPV11-E7 HaCaT cells were cocultured with Jurkat cells, and Jurkat cell apoptosis and proliferation as well as the Jurkat cell cycle were evaluated by flow cytometry and cell counting kit-8 (CCK-8) assays.

RESULTS

PD-L1 was highly expressed in keratinocytes of genital warts. Through the construction of a cell model, we found that HPV11-E7 could upregulate the expression of PD-L1 in HaCaT cells. Furthermore, HPV11-E7 HaCaT cells can promote the apoptosis of Jurkat cells, inhibit the proliferation of Jurkat cells and mediate the cell cycle arrest of Jurkat cells through the PD-1/PD-L1 signalling pathway.

CONCLUSIONS

HPV infection may upregulate PD-L1 expression in the keratinocytes of genital warts and participate in the inhibition of local T-cell function.

A Therapeutic DNA Vaccine Targeting HPV16 E7 in Combination with Anti-PD-1/PD-L1 Enhanced Tumor Regression and Cytotoxic Immune Responses

Persistent infection of high-risk human papillomavirus (HPV) and the expression of E6 and E7 oncoproteins are the main causes of cervical cancer. Several prophylactic HPV vaccines are used in the clinic, but these vaccines have limited efficacy in patients already infected with HPV. Since HPV E7 is vital for tumor-specific immunity, developing a vaccine against HPV E7 is an attractive strategy for cervical cancer treatment. Here, we constructed an HPV16 E7 mutant that loses the ability to bind pRb while still eliciting a robust immune response. In order to build a therapeutic DNA vaccine, the E7 mutant was packaged in an adenovirus vector (Ad-E7) for efficient expression and enhanced immunogenicity of the vaccine. Our results showed that the Ad-E7 vaccine effectively inhibited tumor growth and increased the proportion of interferon-gamma (IFN-γ)-secreting CD8+ T cells in the spleen, and tumor-infiltrating lymphocytes in a mouse cervical cancer model was achieved by injecting with HPV16-E6/E7-expressing TC-1 cells subcutaneously. Combining the Ad-E7 vaccine with the PD-1/PD-L1 antibody blockade significantly improved the control of TC-1 tumors. Combination therapy elicited stronger cytotoxic T lymphocyte (CTL) responses, and IFN-γ secretion downregulated the proportion of Tregs and MDSCs significantly. The expressions of cancer-promoting factors, such as TNF-α, were also significantly down-regulated in the case of combination therapy. In addition, combination therapy inhibited the number of capillaries in tumor tissues and increased the thickness of the tumor capsule. Thus, Ad-E7 vaccination, in combination with an immune checkpoint blockade, may benefit patients with HPV16-associated cervical cancer.

A Comprehensive View of the Cancer-Immunity Cycle (CIC) in HPV-Mediated Cervical Cancer and Prospects for Emerging Therapeutic Opportunities

Cervical cancer (CC) is the fourth most common cancer in women worldwide, with more than 500,000 new cases each year and a mortality rate of around 55%. Over 80% of these deaths occur in developing countries. The most important risk factor for CC is persistent infection by a sexually transmitted virus, the human papillomavirus (HPV). Conventional treatments to eradicate this type of cancer are accompanied by high rates of resistance and a large number of side effects. Hence, it is crucial to devise novel effective therapeutic strategies. In recent years, an increasing number of studies have aimed to develop immunotherapeutic methods for treating cancer. However, these strategies have not proven to be effective enough to combat CC. This means there is a need to investigate immune molecular targets. An adaptive immune response against cancer has been described in seven key stages or steps defined as the cancer-immunity cycle (CIC). The CIC begins with the release of antigens by tumor cells and ends with their destruction by cytotoxic T-cells. In this paper, we discuss several molecular alterations found in each stage of the CIC of CC. In addition, we analyze the evidence discovered, the molecular mechanisms and their relationship with variables such as histological subtype and HPV infection, as well as their potential impact for adopting novel immunotherapeutic approaches.

COVID-19 can lead to rapid progression of cervical intraepithelial neoplasia by dysregulating the immune system: A hypothesis

COVID-19 is a multisystem disease and cause of a global pandemic. Lately, cases of disease progression of HPV-infected CIN under SARS-CoV-2 infection were reported giving rise to the hypothesis of direct virus-infection induced pro-carcinogenic effect of SARS-CoV-2. We herein present a case of rapid progression from HPV-induced CIN 2 to microinvasive carcinoma within three months under COVID-19 without direct virus infection. Histopathologic evaluation, Fluorescence-in-situ hybridization and qRT-PCR against SARS-CoV-2 RNA as well as gene expression analysis were performed from the available FFPE-tissue and accompanied by an analysis of white blood cell differential. No signs of direct SARS-CoV-2 infection or COVID-19 typical alterations of cervical tissue were found. As expected, p53 decreased in expression with progression of dysplasia, while APOBEC3A and VISTA showed a decrease in expression contrary to observations in dysplasia progression. PD-L1 was expressed consistently or increased slightly but did not show the expected strong induction of expression. DNMT1 showed an increase in expression in CIN III and a slight decrease in carcinoma, while DNMT3a is consistently expressed in CIN II and decreased in carcinoma. Blood tests after COVID-19 showed substantial reduction of lymphocytes, eosinophils, T-cells, and NK-cells. Our results hint at an indirect effect of COVID-19 on the cervical neoplasm. We conclude that the immune system might be preoccupied and exhausted by the concurring COVID-19 disease, leading to less immunological pressure on the HPV-infected cervical dysplasia enabling rapid disease progression. Further, indirect proangiogenic and proinflammatory micromilieu due to the multisystemic effects of COVID-19 might play an additional role.

Preliminary Analysis of Cervical Cancer Immunotherapy

Cervical cancer is one of the most common gynecologically malignancies worldwide. Although vaccine and cervical cancer screening including human papillomavirus testing, cytology testing, and colposcopy have developed rapidly in recent years, effectively reducing cervical cancer mortality, cervical cancer remains a malignancy with higher female fatality rates worldwide and has a high risk for socioeconomically disadvantaged groups. The combination of platinum-paclitaxel and chemotherapy, possibly with the addition of bevacizumab, is currently the treatment of choice for advanced cervical cancer, but it only has remission purposes. Therefore, new therapeutic strategies are needed for both locally advanced and metastatic cervical cancer. Here, we make a preliminary analysis of cervical cancer immunotherapy.

PD-1/PD-L1 inhibitors for advanced or metastatic cervical cancer: From bench to bed

Advanced or metastatic cervical cancer has a poor prognosis, and the 5-year overall survival is <5% with conventional radiotherapy and chemotherapy. Immunotherapy, particularly immune checkpoint inhibitors (ICIs), achieved initial success in advanced solid tumors, while their efficacy and safety in advanced or metastatic cervical cancer remains to be explored. Previous studies found high-risk HPV infection and elevated PD-L1 expression in cervical precancerous lesions and squamous cell carcinoma. Meanwhile, elevated PD-L1 expression, high cytotoxic T lymphocyte infiltration, and abnormal cytotoxic T lymphocyte function might benefit inflammation infiltration for ICIs in the tumor microenvironment. Patients with HPV infection, squamous cell carcinoma, advanced stage, large tumor size, poor differentiation, metastatic disease, history of multiple childbirth and abortion, or a previous history of receiving chemotherapy might be associated with positive PD-L1 expression. Although there is no correlation between PD-L1 expression and prognosis using conventional radiotherapy, patients with high PD-L1 expression have a poorer prognosis. Several clinical studies demonstrate preliminary safety and efficacy for PD-1/PD-L1 inhibitors, and the exploration of combination strategies such as immunotherapy combined with chemotherapy, radiotherapy, anti-angiogenesis therapy, or dual ICIs is ongoing. This paper systematically reviews PD-L1 expression patterns and their relationship with prognosis, along with reported and ongoing clinical trials of PD-1/PD-L1 inhibitors in cervical cancer to clarify the prospect of ICIs for cervical cancer from bench to bed.

PD-L1: Can it be a biomarker for the prognosis or a promising therapeutic target in cervical cancer?

Cervical cancer is one of the most common in the female genital tract and remains a leading cause that threatens the health and lives of women worldwide, although preventive vaccines and early diagnosis have reduced mortality. While treatment by operation and chemoradiotherapy for early-stage patients achieve good outcomes, the great majority of cervical cancers caused by the human papilloma virus (HPV) make immunotherapy realizable for patients with advanced and recurrent cervical cancer. To date, some clinical trials of checkpoint immunotherapy in cervical cancer have indicated significant benefits of programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) inhibitors, providing strong evidence for PD-1/PD-L1 as a therapeutic target. In this review article, we discuss the role of PD-L1 and the application of PD-L1 inhibitors in cervical cancer, with the aim of providing direction for future research.

Depletion of Human Papilloma Virus E6- and E7-Oncoprotein-Specific T-Cell Responses in Women Living With HIV

Background

Cervical cancer - caused by persistent High Risk Human Papilloma Virus (HR HPV) infections - is the second most common cancer affecting women globally. HIV infection increases the risk for HPV persistence, associated disease progression and malignant cell transformation. We therefore hypothesized that this risk increase is directly linked to HIV infection associated dysfunction or depletion of HPV-oncoprotein-specific T-cell responses.

Methods

The 2H study specifically included HIV+ and HIV- women with and without cervical lesions and cancer to analyze HPV oncogene-specific T cell responses in relation to HPV infection, cervical lesion status and HIV status. Oncoprotein E6 and E7 specific T-cell responses were quantified for the most relevant types HPV16, 18 and 45 and control antigens (CMV-pp65) and M.tb-PPD in 373 women, using fresh peripheral blood mononuclear cells in an IFN-γ release ELISpot assay.

Results

Overall, systemic E6- and E7-oncoprotein-specific T-cell responses were infrequent and of low magnitude, when compared to CMV-pp65 and M.tb-PPD (p < 0.001 for all HR HPV types). Within HIV negative women infected with either HPV16, 18 or 45, HPV16 infected women had lowest frequency of autologous-type-E6/E7-specific T-cell responses (33%, 16/49), as compared to HPV18 (46% (6/13), p = 0.516) and HPV45 (69% (9/13), p = 0.026) infected women. Prevalent HPV18 and 45, but not HPV16 infections were linked to detectable oncoprotein-specific T-cell responses, and for these infections, HIV infection significantly diminished T-cell responses targeting the autologous infecting genotype. Within women living with HIV, low CD4 T-cell counts, detectable HIV viremia as well as cancerous and precancerous lesions were significantly associated with depletion of HPV oncoprotein-specific T-cell responses.

Discussion

Depletion of HPV-oncoprotein-specific T-cell responses likely contributes to the increased risk for HR HPV persistence and associated cancerogenesis in women living with HIV. The low inherent immunogenicity of HPV16 oncoproteins may contribute to the exceptional potential for cancerogenesis associated with HPV16 infections.

Propofol decreases CD8+ T cells and sevoflurane increases regulatory T cells after lung cancer resection: a randomized controlled trial

Background

Anaesthetics generally have an immunosuppressive effect, which may be related to prognosis. We conducted to clarify the relationship between peri-operative immunosuppression and anaesthetic agents in patients undergoing lung cancer surgery, resulting in better selection of intraoperative anaesthesia.

Methods

Prospective randomized controlled study was performed in single-University hospital. Patients with lung cancer who were scheduled to undergo lung cancer resection between June 2018 and July 2019. Patients were randomly divided to three groups: desflurane (group D), sevoflurane (group S), and propofol (group P) groups. Peripheral blood mononuclear cells were separated from the blood samples. CD4+ and CD8+ T cells, programmed death 1 (PD-1) on CD4+ and CD8+ T cells, and regulatory T cells were measured by flow cytometry. The Wilcoxon signed rank sum test was used to compare pre- and post-operative values for each anaesthesia.

Results

Eighty-two patients were enrolled; samples from 64 individuals (20 in group D, 22 in group S, and 22 in group P) were analysed after exclusion. The number of CD8+ T cells was significantly lower after the operation than before the operation in the group P (P<0.05). The proportion of regulatory T cells was significantly increased after surgery, compared with before surgery in the group S (P<0.05). There was no difference in PD-1 on CD4+ and CD8+ T cells after lung surgery among the three groups.

Conclusions

Propofol decreased the number of CD8+ T cells, while sevoflurane increased the proportion of regulatory T cells in patients after lung surgery; however, propofol, sevoflurane, and desflurane did not increase the proportion of PD-1 on CD4+ and CD8+ T cells after lung surgery. Sevoflurane and propofol may cause immunosuppression via different mechanisms after lung cancer surgery.

Trial Registration

UMIN-CTR: UMIN000031911.

The role of Tim-3/Galectin-9 pathway in T-cell function and prognosis of patients with human papilloma virus-associated cervical carcinoma

The interaction between Tim-3 on T cell and its ligand, Galectin-9, negatively regulates cellular immune responses. However, the role of Tim-3/Galectin-9 pathway in the immune evasion of cervical cancer remains unknown. This study is to investigate the expression, function, and regulation of Tim-3/Galectin-9 signaling pathway in human papilloma virus (HPV) positive cervical cancer. Flow cytometry showed that Tim-3 expression on T cell and Galectin-9 expression on monocytes in HPV positive cervical cancer patients were significantly higher compared to cervical intraepithelial neoplasia and benign uterine fibroids Tim-3 + CD4+ Th1 cells and Tim-3 + CD8+ T cells in HPV positive cervical cancer patients were significantly reduced after surgery. Serum TGF-β and IL-10 levels were positively correlated with Tim-3 + Treg cells, while IFN-γ and IL-2 were negatively correlated with Tim-3 + Th1 cells. Additionally, Tim-3 + CD4+ T cells were positively correlated with Galectin-9 + monocytes. Survival curve analysis showed that Tim-3 + CD4+ T cells were negatively correlated with patient survival, and closely related to FIGO stage, degree of differentiation, and lymph node metastasis of HPV positive cervical cancer. In vitro experiments showed that by blocking the Tim-3/Galectin-9 pathway, the proliferation of T cells and their ability to express IFN-γ, IL-2, perforin, and granzyme B was significantly restored. In conclusion, high levels of Tim-3 and Galectin-9 in HPV positive cervical cancer patients play roles in the progression of disease by promoting Treg cells to inhibit the cytotoxic function of Th1 and CD8+ T cells. Tim-3/Galectin-9 may serve as a new immunotherapy target for patients with HPV positive cervical cancer.

Development of DNA Vaccine Targeting E6 and E7 Proteins of Human Papillomavirus 16 (HPV16) and HPV18 for Immunotherapy in Combination with Recombinant Vaccinia Boost and PD-1 Antibody

Immunotherapy for cervical cancer should target high-risk human papillomavirus types 16 and 18, which cause 50% and 20% of cervical cancers, respectively. Here, we describe the construction and characterization of the pBI-11 DNA vaccine via the addition of codon-optimized human papillomavirus 18 (HPV18) E7 and HPV16 and 18 E6 genes to the HPV16 E7-targeted DNA vaccine pNGVL4a-SigE7(detox)HSP70 (DNA vaccine pBI-1). Codon optimization of the HPV16/18 E6/E7 genes in pBI-11 improved fusion protein expression compared to that in DNA vaccine pBI-10.1 that utilized the native viral sequences fused 3' to a signal sequence and 5' to the HSP70 gene of Mycobacterium tuberculosis Intramuscular vaccination of mice with pBI-11 DNA better induced HPV antigen-specific CD8+ T cell immune responses than pBI-10.1 DNA. Furthermore, intramuscular vaccination with pBI-11 DNA generated stronger therapeutic responses for C57BL/6 mice bearing HPV16 E6/E7-expressing TC-1 tumors. The HPV16/18 antigen-specific T cell-mediated immune responses generated by pBI-11 DNA vaccination were further enhanced by boosting with tissue-antigen HPV vaccine (TA-HPV). Combination of the pBI-11 DNA and TA-HPV boost vaccination with PD-1 antibody blockade significantly improved the control of TC-1 tumors and extended the survival of the mice. Finally, repeat vaccination with clinical-grade pBI-11 with or without clinical-grade TA-HPV was well tolerated in vaccinated mice. These preclinical studies suggest that the pBI-11 DNA vaccine may be used with TA-HPV in a heterologous prime-boost strategy to enhance HPV 16/18 E6/E7-specific CD8+ T cell responses, either alone or in combination with immune checkpoint blockade, to control HPV16/18-associated tumors. Our data serve as an important foundation for future clinical translation.IMPORTANCE Persistent expression of high-risk human papillomavirus (HPV) E6 and E7 is an obligate driver for several human malignancies, including cervical cancer, wherein HPV16 and HPV18 are the most common types. PD-1 antibody immunotherapy helps a subset of cervical cancer patients, and its efficacy might be improved by combination with active vaccination against E6 and/or E7. For patients with HPV16+ cervical intraepithelial neoplasia grade 2/3 (CIN2/3), the precursor of cervical cancer, intramuscular vaccination with a DNA vaccine targeting HPV16 E7 and then a recombinant vaccinia virus expressing HPV16/18 E6-E7 fusion proteins (TA-HPV) was safe, and half of the patients cleared their lesions in a small study (NCT00788164). Here, we sought to improve upon this therapeutic approach by developing a new DNA vaccine that targets E6 and E7 of HPV16 and HPV18 for administration prior to a TA-HPV booster vaccination and for application against cervical cancer in combination with a PD-1-blocking antibody.

Immunotherapy in cervix cancer

The treatment approach to cervix cancer has remained unchanged for several decades and new therapeutic strategies are now required to improve outcomes, as the prognosis is still poor. In the last years, a better understanding of HPV tumor-host immune system interactions and the development of new therapeutics targeting immune checkpoints generated interest in the use of immunotherapy in cervix cancer. Preliminary phase I-II trials demonstrated the efficacy, the duration of responses and the manageable safety of this approach. Currently, many phase II and III studies are ongoing in both locally advanced and metastatic cervical cancer, assessing immunotherapy as a single agent or in combination with chemotherapy and radiotherapy. We reviewed the published data and the therapeutic implications of the most promising novel immunotherapeutic agents under investigation in cervix cancer.

High-Risk HPV Oncoproteins and PD-1/PD-L1 Interplay in Human Cervical Cancer: Recent Evidence and Future Directions

Cervical cancer is the fourth most common malignancy in women worldwide and a leading cause of cancer-related mortality in developing countries. Important etiological factors in this cancer are high-risk human papillomaviruses (HPV), as roughly 96% of cervical cancer cases are positive for these oncoviruses. On the other hand, it has been recently pointed out that E6/E7 oncoproteins of high-risk HPV can upregulate the programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) axis. Likewise, several recent reports showed that checkpoint blockades targeting PD-1/PD-L1 pathways have achieved efficient clinical responses via suppressing cancer progression and improving survival in several types of human cancers including metastatic cervical cancer. In this review, we summarize recent advances in our understanding of the PD-1/PD-L1 signaling pathway and its interaction with high-risk HPV and their oncoproteins, which could have an important impact on the management of HPV-associated cancers including cervical.

Ultrasound-Mediated Co-Delivery of miR-34a and sPD-1 Complexed with Microbubbles for Synergistic Cancer Therapy

Background

miR-34a was downregulated and PD-L1 was upregulated in cervical cancer; however, the treatment of cervical cancer lacks precision and targeting. This study explored the ultrasound-mediated co-delivery of miR-34a and sPD-1 complexes with microbubbles for synergistic cancer therapy.

Methods

Cationic lipid microbubbles (CLMBs) were prepared by membrane hydration and mechanical oscillation. U14 subcutaneous xenograft mice were injected with CLMBs-loaded sPD-1 and miR-34a combined with ultrasound targeted destruction, and tumor volume and tumor weight of mice were measured. TUNEL apoptosis test and the mRNA expression of apoptosis-related gene Bcl-2 and Bax were analyzed by qRT-PCR. Antitumor immune-related cytokines IFN-γ were investigated by qRT-PCR, LDH Cytotoxicity Assay Kit were performed to test cytotoxic T lymphocytes (CTL).

Results

CLMBs were successfully prepared and the plasmid bound to its surface. The tumor volume and weight were specifically decreased by ultrasound-mediated co-delivery of miR-34a and sPD-1 complexes with microbubbles, apoptosis was induced and the apoptosis suppressor gene Bcl-2 was downregulated and proapoptotic gene Bax were upregulated. qRT-PCR analysis revealed that antitumor immunity-related IFN-γ was strongly upregulated in mice, which were treated with CLMBs-loaded sPD-1 and miR-34a combined with ultrasound targeted destruction, and the percentage of CTL was increased.

Conclusion

These findings from the study demonstrated that CLMBs could deliver miR-34a and sPD-1, combined with ultrasound targeted destruction, could suppress the tumor tissue growing, induce apoptosis and enhance antitumor immunity in U14 subcutaneous xenograft mice.

Producing Soluble Human Programmed Cell Death Protein-1: A Natural Supporter for CD4+T Cell Cytotoxicity and Tumor Cells Apoptosis

BACKGROUND

Programmed cell death protein-1 (PD-1)/PD-L1 pathway is one of the immune checkpoint pathways involved in the regulation of the immune responses and the suppression of anti-tumor defense. PD-1/PD-L1 blocking antibodies improve immune responses such as cytotoxic activity of CD8+/CD4+T cells and increase mortality of tumor cells as well; however, their use is accompanied by adverse side effects.

OBJECTIVES

We aimed to produce a native blocker of human PD-1/PD-L1, for developing T cells cytotoxicity and tumor cells apoptosis.

MATERIALS AND METHODS

We designed and cloned soluble human PD-1-GFP-pcDNA3.1/hygro construct in Escherichia coli strain TOP10 cells and then transfected this construct into the HEK cells. The concentration of the secreted shPD-1 in the supernatant was measured and the supernatant was used for blocking PD-L1 on the MDA-MB-231 cells. The cytotoxicity of CD8+/CD4+T cells and the apoptosis of MDA-MB-231 cells, under the influence of shPD-1 in the co-culture of T cells with the MDA-MB-231 cells, were evaluated using flow cytometry technique.

RESULTS

The GFP expression in the transfected cells illustrated the successful designing, transfection, and production of shPD-1. Soluble human PD-1 concentration in the supernatant of the transfected HEK cells was significantly higher than the untransfected cells. In addition, shPD-1 significantly blocked PD-L1 on the MDA- MB-231 cells, improved the cytotoxicity of CD4+T cells, and increased the apoptosis of MDA-MB-231 cells.

CONCLUSION

Overall, increased CD4+T cell cytotoxicity and tumor cells apoptosis under the influence of shPD-1, confirmed the effectiveness of shPD-1 as a natural blocker of PD-L1and as an augmenter of the anti-tumorimmune responses.

A Brief Review about the Role of Nanomaterials, Mineral-Organic Nanoparticles, and Extra-Bone Calcification in Promoting Carcinogenesis and Tumor Progression

People come in contact with a huge number of nanoparticles (NPs) throughout their lives, which can be of both natural and anthropogenic origin and are capable of entering the body through swallowing, skin penetration, or inhalation. In connection with the expanding use of nanomaterials in various industrial processes, the question of whether there is a need to study the potentially adverse effects of NPs on human health becomes increasingly important. Despite the fact that the nature and the extent of damage caused depends on the chemical and the physical characteristics of individual NPs, there are also general mechanisms related to their toxicity. These mechanisms include the ability of NPs to translocate to various organs through endocytosis, as well as their ability to stimulate the production of reactive oxygen species (ROS), leading to oxidative stress, inflammation, genotoxicity, metabolic changes, and potentially carcinogenesis. In this review, we discuss the main characteristics of NPs and the effects they cause at both cellular and tissue levels. We also focus on possible mechanisms that underlie the relationship of NPs with carcinogenesis. We briefly summarize the main concepts related to the role of endogenous mineral organic NPs in the development of various human diseases and their participation in extra-bone calcification. Considering data from both our studies and those published in scientific literature, we propose the revision of some ideas concerning extra-bone calcification, since it may be one of the factors associated with the initiation of the mechanisms of immunological tolerance.

The role of the innate and adaptive immune response in HPV-associated oropharyngeal squamous cell carcinoma

Human papilloma virus (HPV) has been implicated in the development of oropharyngeal squamous cell carcinoma (OPSCC) and is directly attributed to its increasing incidence. The immune microenvironment surrounding HPV‐associated OPSCC tumors is complex and plays a critical role in the carcinogenic process. The neoplastic mechanism includes cells of the innate immunity such as macrophages, and dendritic cells as well as cells of the adaptive immune process such as CD8+ T‐cells. The intricate interactions between these two arms of the immune system allow for a pro‐inflammatory and pro‐tumorigenic environment. Intensive efforts are underway to gain a greater understanding of the mechanisms involved in the immune system's role in tumor development. This study seeks to summarize the current knowledge pertaining to role of the innate and adaptive immune response in HPV‐associated OPSCC.

Level of Evidence

3a

PD-1/PD-L1 blockade in cervical cancer: current studies and perspectives

Cervical cancer (CC) is the fourth most commonly diagnosed female malignancy and a leading cause of cancer-related mortality worldwide, especially in developing countries. Despite the use of advanced screening and preventive vaccines, more than half of all CC cases are diagnosed at advanced stages, when therapeutic options are extremely limited and side effects are severe. Given these circumstances, new and effective treatments are needed. In recent years, exciting progress has been made in immunotherapies, including the rapid development of immune checkpoint inhibitors. Checkpoint blockades targeting the PD-1/PD-L1 axis have achieved effective clinical responses with acceptable toxicity by suppressing tumor progression and improving survival in several tumor types. In this review, we summarize recent advances in our understanding of the PD-1/PD-L1 signaling pathway, including the expression patterns of PD-1/PD-L1 and potential PD-1/PD-L1-related therapeutic strategies for CC.

PD-1/PD-L1 Inhibitors in Cervical Cancer

Cervical cancer is one of the most common gynecological tumors, and the majority of early-stage cervical cancer patients achieve good recovery through surgical treatment and concurrent chemoradiotherapy (CCRT). However, for patients with recurrent, persistent, metastatic cervical cancer, effective treatment is rare, except for bevacizumab combined with chemotherapy. Programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) inhibitors might be a novel choice to improve the clinical outcomes of these patients. Thus far, some pivotal trials, including Keynote 028, Keynote 158 and Checkmate 358, have indicated established clinical benefit of PD-1/PD-L1 inhibitors in cervical cancer. In light of these data, the FDA has approved pembrolizumab for patients with recurrent or metastatic cervical cancer with disease progression during or after chemotherapy. There are also some ongoing studies that may provide more evidence for the PD-1/PD-L1 pathway as a therapeutic target in cervical cancer. In this review, we have summarized the status and application of PD-1/PD-L1 inhibitors in clinical trials for the treatment of cervical cancer and suggested some future directions in this field.

Modulation of antigen presenting cell functions during chronic HPV infection

High-risk human papillomaviruses (HR-HPV) infect basal keratinocytes, where in some individuals they evade host immune responses and persist. Persistent HR-HPV infection of the cervix causes precancerous neoplasia that can eventuate in cervical cancer. Dendritic cells (DCs) are efficient in priming/cross-priming antigen-specific T cells and generating antiviral and antitumor cytotoxic CD8+ T cells. However, HR-HPV have adopted various immunosuppressive strategies, with modulation of DC function crucial to escape from the host adaptive immune response. HPV E6 and E7 oncoproteins alter recruitment and localization of epidermal DCs, while soluble regulatory factors derived from HPV-induced hyperplastic epithelium change DC development and influence initiation of specific cellular immune responses. This review focuses on current evidence for HR-HPV manipulation of antigen presentation in dendritic cells and escape from host immunity.

Ginsenoside Rg3 targets cancer stem cells and tumor angiogenesis to inhibit colorectal cancer progression in vivo

Anti-angiogenic therapy has been successfully applied to treat colorectal cancer (CRC). Ginsenoside Rg3, derived from the Chinese herb ginseng, has anti-vascularization effects and can inhibit tumor growth and metastasis, and can sensitize cancer cells to chemotherapy. Therefore, in the present study, we investigated whether Rg3 could be appropriate for CRC treatment. Growth of CRC cells was assessed by an MTT (methyl thiazolyl tetrazolium) assay in vitro and using orthotopic xenograft models in vivo. mRNA expression was evaluated using real-time PCR. Protein levels were tested by western blotting, flow cytometry and immunohistochemistry. Migration was determined using a wound-healing assay. Stemness was further confirmed using a plate clone formation assay. We found that Rg3 repressed the growth and stemness of CRC cells both in vitro and in vivo. Rg3 also impaired the migration of CRC cells in vitro. Rg3 downregulated the expressions of angiogenesis-related genes, and repressed the vascularization of CRC xenografts. In addition, Rg3 strengthened the cytotoxicity of 5-Fluorouracil and oxaliplatin against orthotopic xenografts in vivo. Moreover, Rg3 downregulated the expressions of B7-H1 and B7-H3, high expressions of which were associated with reduced overall survival (OS) of CRC patients. Hence, Rg3 not only repressed the growth and stemness of CRC cells, but could also remodel the tumor microenvironment through repressing angiogenesis and promoting antitumor immunity. Therefore, Rg3 could be a novel therapeutic for the CRC treatment.

Suppressed Programmed Death 1 Expression on CD4+ and CD8+ T Cells in Psoriatic Patients

Psoriasis is a chronic inflammatory disease mediated by T cell immunity. Programmed death 1 (PD-1), a coinhibitory receptor, plays an important role in immune regulation and maintaining peripheral tolerance. The aim of the study was to compare the expression of PD-1 on the peripheral T cells between psoriatic patients and healthy controls. The study included 75 psoriatic patients and 52 healthy volunteers. The percentages and absolute numbers of CD3⁺, CD4⁺, CD8⁺, CD4⁺PD-1⁺, and CD8⁺PD-1⁺ T cells were analyzed using flow cytometry. The absolute numbers and percentages of CD4⁺PD-1⁺ and CD8⁺PD-1⁺ T cells were significantly decreased in the psoriatic patients in comparison with the control group. No significant correlations were found between the absolute numbers and percentages of CD4⁺PD-1⁺ or CD8⁺PD-1⁺ T cells and clinical characteristics of psoriasis. Decreased PD-1 expression on the T cells may be responsible for impaired negative regulation of immune response in psoriasis pathogenesis.

T- and NK-cell populations with regulatory phenotype and markers of apoptosis in circulating lymphocytes of patients with CIN3 or microcarcinoma of the cervix: evidence for potential mechanisms of immune suppression

BACKGROUND

Processes and mechanisms responsible for systemic immune suppression in early-stage cervical cancer remain substantially underinvestigated. In this work, we focused on studying the frequencies of circulating regulatory T (CD4 and CD8 Tregs) and NK (NKregs) cells in parallel with assessment of apoptotic markers expression in T cells from patients with preinvasive and microinvasive cervical cancer, with the aim to determine whether up-regulation of apoptosis-associated markers in Т lymphocytes accompanies cervical cancer development and correlates with the change in percentages of regulatory cell populations at systemic level during the initial stages of invasive cervical cancer progression.

METHODS

Fourty two women with histologically confirmed cervical intraepithelial neoplasia grade 3 (CIN3, including carcinoma in situ) or cervical cancer (stage IA) and 30 healthy women (control) were enrolled in the study. Peripheral blood samples were taken immediately before surgery or any treatment and immediately subjected to multicolor flow cytometry.

RESULTS

Analysis of a combination of CD4/CD8, CD25, CD127, and FoxP3 markers revealed a statistically significant increase in the frequencies of Tregs within both the CD4 and CD8 subsets of circulating lymphocytes in patients with CIN3 and stage IA cancer. In contrast, lower numbers of NKregs (defined as CD16^dim/negCD56^bright subpopulation) and increased CD56^dim/CD56^bright NK ratio were found in patients compared to controls, with the percentage of CD16^brightCD56^dim cells (major subtype of circulating NKs) showing no difference. Patients also exhibited an increased expression of CD95 in total peripheral blood T lymphocytes, along with increased level of Annexin V binding to CD95-positive cells, suggesting higher susceptibility of T cells to apoptosis and potential involvement of CD95-dependent pathway in early-stage cervical cancer. Differential analysis of CD4 and CD8 T cells revealed different trends in the change of CD95 expression, confirming that this change likely has different functional significance for these two subsets. A search for correlations between the phenotypic parameters analyzed in this study was performed to demonstrate that women with early neoplastic lesions of the cervix, such as carcinoma in situ and microinvasive carcinoma, displayed a coordinated increase in expression of Treg markers in circulating lymphocytes, along with more pronounced cross-relationships between Treg numbers, CD95 expression on T cells, and apoptosis, compared to the control group.

CONCLUSIONS

The results of this study suggest that a diversity of immune regulatory mechanisms that provide support for initial stages of invasive growth in cervical cancer patients includes systemic changes in the ratios between the principal regulatory and effector lymphocyte populations both within adaptive and innate immunity.

Association between PD-L1 and HPV status and the prognostic value for HPV treatment in premalignant cervical lesion patients

The difference of PD-L1 expression between only HPV-positive patients and premalignant cervical lesion patients did not be reported in present studies. And to test the PD-L1 expression in some cervical cell lesion studies using cervical exfoliated cells sample also was ignored. Meanwhile, the PD-L1 expression as a predictive biomarker still existed controversy. So in the study, first to compare the expression of PD-L1 between only HPV-positive patients and premalignant cervical lesion patients, then to research the association between PD-L1 and HPV status, lastly to explore the possible prognostic value for HPV treatment in premalignant cervical lesion patients.Cervical exfoliated cells samples of 54 premalignant cervical lesion patients with HPV16 infection were collected; meanwhile the cervical exfoliated cells samples from 20 healthy women without HPV infection and 20 patients with only HPV16 infection but cervical cytology normal were collected as 2 control groups. Flow-through hybridization and gene chip (FHGC) was used to detect the HPV type, the PD-L1 expression was tested by Flow cytometry analysis, the methylation-sensitive high-resolution melting (MS-HRM) was used to test the HPV16 L1 gene methylation. The 54 premalignant cervical lesion patients were followed up in 18 months to assess the prognostic value of PD-L1 for HPV treatment.The PD-L1 positive cell rate and mean fluorescence intensity of PD-L1 positive cell in premalignant cervical lesion patients with HPV16 infection were higher than 2 control groups. Mean fluorescence intensity of PD-L1 positive cell were increased in 54 cases when existing multiple HPV status and high HPV16-L1 gene methylation (L1 gene methylation more than 50%). High PD-L1 expression (PD-L1 positive cell rate more than 10%), high HPV16-L1 gene methylation, and multiple HPV infection status could prolong the time to clean HPV infection by Kaplan-Meier analysis. Multivariate Cox proportional hazards analysis also showed that all of high PD-L1 expression, high HPV-L1 methylation, and multiple HPV infection status should increase the risk of HPV unclearance in premalignant cervical lesion patients; the hazard ratio (HR) was 2.043 (CI: 1.050-3.973), 2.797 (CI: 1.277-6.122), and 3.050 (CI: 1.406-6.615).PD-L1 expression only was correction with HPV infection when the infection induced the cervical cells to create the lesion. PD-L1 was the risk factor of HPV unclearance in premalignant cervical lesion patients, so anti-PD-L1 therapy could be a potential effectiveness way of HPV infection in premalignant cervical lesion patients.