• 생명과학회지
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• 제11권4호
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• pp.362-370
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• 2001

Regulation of cell proliferation is a complex process involving the regulated expression and /or modification of discrete gene products. which control transition between different stages of the cycle. The purpose of this short review is to provide an overview of somatic cell cycle events and their controls. Cycline have appeared as major positive regulators in this network, because their association to the cyclin-dependent kinases(Cdks) allows the subsequent activation on the Cdk/cyclin complexes and their catalatic activity. In mammalian cells, early to mid G1 progression and late G1 progression leading to S phase entry are directed by D-type cyclins-Cdk4, 6 and cyclin E-Cdk 2 both of which can phosphorylate the retinoblastoma protein (pRB). pRB is a transcriptional repressor which, in its unphosphorylated state, binds to members of the E2F transcription factor family and blocks E2F-dependent transcription of genes controlling the G1 to S phase transition an subsequent DNA synthesis. Cyclin A is produced in late G1 and expressed during S and G2 phae, and expression of B-type cyclins is typically maximal during the G2 to M phase transition and it controls the passage through M phase. They primarily associate with the activate Cdk2, and Cdc2, respectively. On the other hand, the Cdk inhibitors negatively control the activity of C아/cyclin complex by coordinating internal and/or external signals and impending proliferation at several key checkpoints. These current and further findings will provide novel approaches to understanding and treating major diseases.

• 대한두경부종양학회지
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• 제33권1호
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• pp.1-5
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• 2017

두경부 편평상피세포암은 전세계적으로 6번째로 흔하며 예후가 불량한 암종이다. 면역 감시는 두경부암의 발생과 진행을 억제하는 중요한 기전으로 알려져 있다. 두경부암세포는 면역 감시를 T세포의 관용을 유도하거나 체크포인트를 통한 T세포 기능을 억제하는 등의 방법으로 회피할 수 있다. 한편 진행성 두경부암 임상연구에서 체크포인트 억제제는 명확한 항종양효과를 입증하였다. 이처럼 면역항암제가 중요한 암치료 방법으로 떠오르는 이때에 본 종설은 두경부암의 면회회피 기전 및 임상적용근거에 대한 최근 지식을 정리하였다.

• Journal of Chest Surgery
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• 제56권2호
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• pp.67-74
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• 2023

Perioperative treatment with conventional cytotoxic chemotherapy for resectable non-small cell lung cancer (NSCLC) has proven clinical benefits in terms of achieving a higher overall survival (OS) rate. With its success in the palliative treatment of NSCLC, immune checkpoint blockade (ICB) has now become an essential component of treatment, even as neoadjuvant or adjuvant therapy in patients with operable NSCLC. Both pre- and post-surgery ICB applications have proven clinical efficacy in preventing disease recurrence. In addition, neoadjuvant ICB combined with cytotoxic chemotherapy has shown a significantly higher rate of pathologic regression of viable tumors compared with cytotoxic chemotherapy alone. To confirm this, an early signal of OS benefit has been shown in a selected population, with programmed death ligand 1 expression ≥50%. Furthermore, applying ICB both pre- and post-surgery enhances its clinical benefits, as is currently under evaluation in ongoing phase III trials. Simultaneously, as the number of available perioperative treatment options increases, the variables to be considered for making treatment decisions become more complex. Thus, the role of a multidisciplinary team-based treatment approach has not been fully emphasized. This review presents up-to-date pivotal data that lead to practical changes in managing resectable NSCLC. From the medical oncologist's perspective, it is time to dance with surgeons to decide on the sequence of systemic treatment, particularly the ICB-based approach, accompanying surgery for operable NSCLC.

• 대한두경부종양학회지
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• 제37권2호
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• pp.1-9
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• 2021

Thyroid cancer refers to various cancers arising from thyroid gland. Differentiated thyroid cancers (DTCs) include papillary, follicular, and Hurthle cell carcinomas and represent cancers retain normal thyroid functions such as iodine uptake. Radioactive iodine (RAI) is generally used for upfront treatment of metastatic DTCs, but RAI refractory DTCs remain to be clinical challenges. Sorafenib and lenvatinib were approved for the treatment of RAI refractory DTCs and more recently, genomics-based targeted therapies have been developed for NTRK and RET gene fusion-positive DTCs. Poorly differentiated and anaplastic thyroid cancers (ATCs) are extremely challenging diseases with aggressive courses. BRAF/MEK inhibition has been proven to be highly effective in BRAF V600E mutation-positive ATCs and immune checkpoint inhibitors have shown promising activities. Medullary thyroid cancers, which arise from parafollicular cells of thyroid, represent a unique subset of thyroid cancer and mainly driven by RET mutation. In addition to vandetanib and cabozantinib, highly specific RET inhibitors such as selpercatinib and pralsetinib have demonstrated impressive activity and are in clinical use.

• Molecules and Cells
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• 제28권1호
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• pp.37-42
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• 2009

Iron binding lactoferrin (Lf) is involved in the control of cell cycle progression. However, the molecular basis underlying the effects of Lf on cell cycle control, as well as its target genes, remains incompletely understood. In this study, we have demonstrated that a relatively low level of ironsaturated Lf, Lf($Fe^{3+}$), can stimulate S phase cell cycle entry, and requires Akt activation in MCF-7 cells. Lf($Fe^{3+}$) immediately induced Akt phosphorylation at Ser473, which subsequently induced the phosphorylation of two G1-checkpoint Cdk inhibitors, $p21^{Cip/WAF1}$ and $p27^{kip1}$. The Lf($Fe^{3+}$)-induced phosphorylation of Cdk inhibitors impaired their nuclear import behavior, thereby inducing cell cycle progression. However, the treatment of cells with a PI3K inhibitor, LY294002, almost completely blocked Lf($Fe^{3+}$)-stimulated cell cycle progression. LY294002 treatment abrogated Lf($Fe^{3+}$)-induced Akt activation, and prevented the cytoplasmic localization of $p27^{kip1}$. Higher levels of $p21^{Cip/WAF1}$ were also detected in the cytoplasmic sub-cellular compartment as a measure of cellular response to Lf($Fe^{3+}$). Consequently, the degree of phosphorylation of retinoblastoma protein was enhanced in response to Lf($Fe^{3+}$). Therefore, we conclude that Lf($Fe^{3+}$), as a potential antagonist of Cdk inhibitors, can facilitate the functions of E2F during progression to S phase via the Akt signaling pathway.

• 대한의생명과학회지
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• 제25권3호
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• pp.201-210
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• 2019

The oncolytic viruses selectively infect and destroy cancer cells, not harming normal cells. The cancer cell materials released by oncolysis, like tumor antigens, stimulate host antitumor immune responses, which is a long-lasting antitumor immunity removing cancer cells in remote parts of the body by a systemic response. Oncolytic viruses armed with transgenes such as cytokines or other immune stimulating factors enhance the immune responses. The first oncolytic virus approved by US-FDA is $Imlygic^{(R)}$ targeting for melanoma. The oncolytic virus is considered as a revolutionary immunotherapy for tumors together with immune checkpoint inhibitors. A variety of oncolytic viruses are under research in the treatment of kidney cancer, liver cancer, breast cancer, and many others solid tumors. Clinical trials have shown promising results in different types of cancers. Here, we present a brief introduction of various aspects of oncolytic virus, and a review of the current status of oncolytic virus therapy development.

• BMB Reports
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• 제54권1호
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• pp.21-30
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• 2021

Clinical trials have demonstrated that an increased number of effector cells, especially tumor-specific T cells, is positively linked with patients' prognosis. Although the discovery of checkpoint inhibitors (CPIs) has led to encouraging progress in cancer immunotherapy, the lack of either T cells or targets for CPIs is a limitation for patients with poor prognosis. Since interleukin (IL)-2 and IL-7 are cytokines that target many aspects of T-cell responses, they have been used to treat cancers. In this review, we focus on the basic biology of how these cytokines regulate T-cell response and on the clinical trials using the cytokines against cancer. Further, we introduce several recent studies that aim to improve cytokines' biological activities and find the strategy for combination with other therapeutics.

• BMB Reports
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• 제54권1호
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• pp.70-88
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• 2021

Immunotherapy has revolutionized the landscape of cancer treatment and become a standard pillar of the treatment. The two main drivers, immune checkpoint inhibitors and chimeric antigen receptor T cells, contributed to this unprecedented success. However, despite the striking clinical improvements, most patients still suffer from disease progression because of the evolution of primary or acquired resistance. This mini-review summarizes new treatment options including novel targets and interesting combinational approaches to increase our understanding of the mechanisms of the action of and resistance to immunotherapy, to expand our knowledge of advances in biomarker and therapeutics development, and to help to find the most appropriate option or a way of overcoming the resistance for cancer patients.

• Biomolecules & Therapeutics
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• 제32권1호
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• pp.1-12
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• 2024

Adverse drug reactions (ADRs) are an inherent aspect of drug use. While approximately 80% of ADRs are predictable, immune system-mediated ADRs, often unpredictable, are a noteworthy subset. Skin-related ADRs, in particular, are frequently unpredictable. However, the wide spectrum of skin manifestations poses a formidable diagnostic challenge. Comprehending the pathomechanisms underlying ADRs is essential for accurate diagnosis and effective management. The skin, being an active immune organ, plays a pivotal role in ADRs, although the precise cutaneous immunological mechanisms remain elusive. Fortunately, clinical manifestations of skin-related ADRs, irrespective of their severity, are frequently rooted in immunological processes. A comprehensive grasp of ADR morphology can aid in diagnosis. With the continuous development of new pharmaceuticals, it is noteworthy that certain drugs including immune checkpoint inhibitors have gained notoriety for their association with ADRs. This paper offers an overview of immunological mechanisms involved in cutaneous ADRs with a focus on clinical features and frequently implicated drugs.

• Journal of Korean Neurosurgical Society
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• 제64권2호
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• pp.271-281
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• 2021

Objective : Immune checkpoint inhibitors (ICIs) are approved for treating non-small-cell lung cancer (NSCLC); however, the safety and efficacy of combined ICI and Gamma Knife radiosurgery (GKS) treatment remain undefined. In this study, we retrospectively analyzed patients treated with ICIs with or without GKS at our institute to manage patients with brain metastases from NSCLC. Methods : We retrospectively reviewed medical records of patients with brain metastases from NSCLC treated with ICIs between January 2015 and December 2017. Of 134 patients, 77 were assessable for brain responses and categorized into three groups as follows : group A, ICI alone (n=26); group B, ICI with concurrent GKS within 14 days (n=24); and group C, ICI with non-concurrent GKS (n=27). Results : The median follow-up duration after brain metastasis diagnosis was 19.1 months (range, 1-77). At the last follow-up, 53 patients (68.8%) died, 20 were alive, and four were lost to follow-up. The estimated median overall survival (OS) of all patients from the date of brain metastasis diagnosis was 20.0 months (95% confidence interval, 12.5-27.7) (10.0, 22.5, and 42.1 months in groups A, B, and C, respectively). The OS was shorter in group A than in group C (p=0.001). The intracranial disease progression-free survival (p=0.569), local progression-free survival (p=0.457), and complication rates did not significantly differ among the groups. Twelve patients showed leptomeningeal seeding (LMS) during follow-up. The 1-year LMS-free rate in treated with ICI alone group (69.1%) was significantly lower than that in treated with GKS before ICI treatment or within 14 days group (93.2%) (p=0.004). Conclusion : GKS with ICI showed no favorable OS outcome in treating brain metastasis from NSCLC. However, GKS with ICI did not increase the risk of complications. Furthermore, compared with ICI alone, GKS with ICI may be associated with a reduced incidence of LMS. Further understanding of the mechanism, which remains unknown, may help improve the quality of life of patients with brain metastasis.