Spatial-temporal transmission dynamics of HIV-1 CRF01_AE in Indonesia.

Human immunodeficiency virus type 1 (HIV-1) remains a serious health threat in Indonesia. In particular, the CRF01_AE viruses were the predominant HIV-1 strains in various cities in Indonesia. However, information on the dynamic transmission characteristics and spatial-temporal transmission of HIV-1 CRF01_AE in Indonesia is limited. Therefore, the present study examined the spatial-temporal transmission networks and evolutionary characteristics of HIV-1 CRF01_AE in Indonesia. To clarify the epidemiological connection between CRF01_AE outbreaks in Indonesia and the rest of the world, we performed phylogenetic studies on nearly full genomes of CRF01_AE viruses isolated in Indonesia. Our results showed that five epidemic clades, namely, IDN clades 1-5, of CRF01_AE were found in Indonesia. To determine the potential source and mode of transmission of CRF01_AE, we performed Bayesian analysis and built maximum clade credibility trees for each clade. Our study revealed that CRF01_AE viruses were commonly introduced into Indonesia from Southeast Asia, particularly Thailand. The CRF01_AE viruses might have spread through major pandemics in Asian countries, such as China, Vietnam, and Laos, rather than being introduced directly from Africa in the early 1980s. This study has major implications for public health practice and policy development in Indonesia. The contributions of this study include understanding the dynamics of HIV-1 transmission that is important for the implementation of HIV disease control and prevention strategies in Indonesia.

The CpxRA two-component system of adherent and invasive Escherichia coli contributes to epithelial cell invasion and early-stage intestinal fitness in a dysbiotic mouse model mediated by type 1 fimbriae expression.

Adherent and invasive Escherichia coli (AIEC) is a pathobiont that is involved in the onset and exacerbation of Crohn's disease. Although the inducible expression of virulence traits is a critical step for AIEC colonization in the host, the mechanism underlying AIEC colonization remains largely unclear. We here showed that the two-component signal transduction system CpxRA contributes to AIEC gut competitive colonization by activating type 1 fimbriae expression. CpxRA from AIEC strain LF82 functioned as a transcriptional regulator, as evidenced by our finding that an isogenic cpxRA mutant exhibits reduced expression of cpxP, a known regulon gene. Transcription levels of cpxP in LF82 increased in response to envelope stress, such as exposure to antimicrobials compromising the bacterial membrane, whereas the cpxRA mutant did not exhibit this response. Furthermore, we found that the cpxRA mutant exhibits less invasiveness into host cells than LF82, primarily due to reduced expression of the type 1 fimbriae. Finally, we found that the cpxRA mutant is impaired in gut competitive colonization in a mouse model. The colonization defects were reversed by the introduction of a plasmid encoding the cpxRA gene or expressing the type 1 fimbriae. Our findings indicate that modulating CpxRA activity could be a promising approach to regulating AIEC-involved Crohn's disease.

Granular Cell Tumor Mimicking Breast Carcinoma: A Report of Two Cases.

Granular cell tumor (GCT) of the breast is a rare neoplasm that can mimic the clinical and radiological features of breast carcinoma. This paper presents two case reports - a rare male case and a more common female case - to underline the diagnostic challenges posed by GCT in the breast. The male patient was initially suspected of having a breast tumor based on mammography and ultrasound findings. The female patient also exhibited radiological signs suggestive of breast cancer. In both cases, the mammograms showed irregular lesions, while ultrasounds revealed solid masses with posterior shadowing and echogenic halos, mimicking carcinoma. Dynamic contrast-enhanced magnetic resonance imaging (MRI) suggested benign patterns in both cases, but only histopathologic examination post-core needle biopsy confirmed the diagnosis of GCT. These cases highlight the variability of GCT imaging presentations and the potential for misdiagnosis as breast carcinoma. The tumors exhibited distinct histopathological features, such as large polygonal cells with granular eosinophilic cytoplasm and S100 protein, differentiating them from breast carcinoma. However, imaging alone proved insufficient for diagnosis, emphasizing the need for histopathologic confirmation. The report discusses the importance of including GCT in differential diagnoses and utilizing core needle biopsy for accurate evaluation. Both cases had no recurrence during follow-up after wide resection, indicating a favorable prognosis for GCT when properly managed.

A genome-wide association study identified PTPN2 as a population-specific susceptibility gene locus for primary biliary cholangitis.

BACKGROUND AIMS: Previous genome-wide association studies (GWAS) have indicated the involvement of shared (population-non-specific) and non-shared (population-specific) susceptibility genes in the pathogenesis of primary biliary cholangitis (PBC) among European and East-Asian populations. Although a meta-analysis of these distinct populations has recently identified more than 20 novel PBC susceptibility loci, analyses of population-specific genetic architecture are still needed for a more comprehensive search for genetic factors in PBC. APPROACH RESULTS: Protein tyrosine phosphatase non-receptor type 2 (PTPN2) was identified as a novel PBC susceptibility gene locus through a GWAS and subsequent genome-wide meta-analysis involving 2,181 cases and 2,699 controls from the Japanese population (GWAS-lead variant: rs8098858, p=2.6×10-8). In-silico and in-vitro functional analyses indicated that the risk allele of rs2292758, which is a primary functional variant, decreases PTPN2 expression by disrupting Sp1 binding to the PTPN2 promoter in T follicular helper cells (Tfh) and plasmacytoid dendritic cells (pDCs). Infiltration of PTPN2-positive T-cells and pDCs were confirmed in the portal area of the PBC-liver by immunohistochemistry. Furthermore, transcriptomic analysis of PBC-liver samples indicated the presence of a compromised negative feedback loop in-vivo between PTPN2 and IFNG in patients carrying the risk allele of rs2292758. CONCLUSIONS: PTPN2, a novel susceptibility gene for PBC in the Japanese population, may be involved in the pathogenesis of PBC via an insufficient negative feedback loop caused by the PTPN2 risk allele of rs2292758 in IFN signaling. This suggests that PTPN2 could be a potential molecular target for PBC treatment.

Possible link between colonization of the gastrointestinal tract by Citrobacter rodentium in C57BL/6 mice and microbiota composition.

Colonization resistance, conferred by the host's microbiota through both direct and indirect protective actions, serves to protect the host from enteric infections. Here, we identified the specific members of the gut microbiota that impact gastrointestinal colonization by Citrobacter rodentium, a murine pathogen causing colonic crypt hyperplasia. The gut colonization levels of C. rodentium in C57BL/6 mice varied among breeding facilities, probably due to differences in microbiota composition. A comprehensive analysis of the microbiota revealed that specific members of the microbiota may influence gut colonization by C. rodentium, thus providing a potential link between the two.

Advanced Ceramics with Dual Functions of Healing and Decomposition.

This study developed advanced ceramic materials with both healing and decomposition functions using a metastable product generated under superheated steam. The developed composite material comprises ZrC particles dispersed in a yttria-stabilized zirconia (YSZ) matrix. After introducing a surface crack of approximately 120 µm on the composite specimen, it showed a complete strength recovery rate after one hour of heat treatment under superheated steam at 400 °C, while it exhibited a decomposition behavior after one hour of heat treatment in air at 400 °C. The XRD analysis of the heat-treated specimens showed that the final product was monoclinic ZrO2 under both steam and air conditions. In other words, full strength recovery in superheated steam was achieved by a chain reaction involving metastable intermediate products derived from H2O, unlike the reaction in air.

Primary Malignant Melanoma of the Esophagus Treated with Surgical Resection at an Early Stage.

Introduction: Primary malignant melanoma of the esophagus is a very rare disease with a poor prognosis. We herein report a patient with primary malignant melanoma of the esophagus who underwent surgical resection. Case Presentation: A 73-year-old female underwent an upper gastrointestinal endoscopy during follow-up for colonic diverticulitis. An endoscopic examination and constructed radiography revealed a slightly elevated black pigmented lesion in the upper esophagus and a black pigmented area in the esophagogastric junction. Through a preoperative endoscopic biopsy, she was diagnosed with malignant melanoma of the esophagus. We performed thoracoscopy-assisted and laparoscopy-assisted subtotal esophagectomy with lymphadenectomy. The surgical specimens were subjected to immunohistochemical analysis, resulting in a diagnosis of malignant melanoma. The tumor cells were positive for Melan-A and HMB-45 diffusely, supporting that diagnosis. We performed surgical resection in a case of primary malignant melanoma of the esophagus, and the patient has remained disease free for 2 years since the surgery. Conclusion: Early diagnosis and radical resection may be essential for long-term survival in patients with malignant melanoma of the esophagus.

Granulocyte-Colony Stimulating Factor (G-CSF)-Induced Aortitis: A Case Report.

Pegylated granulocyte colony-stimulating factor (G-CSF), commonly used in chemotherapy-induced neutropenia, has been associated with rare instances of aortitis. This study describes a 67-year-old female patient with estrogen receptor (ER)-positive, human epidermal growth factor receptor-2-positive breast cancer, undergoing chemotherapy with an epirubicin/cyclophosphamide (EC) regimen (epirubicin, cyclophosphamide) and pegylated G-CSF for neutropenia prophylaxis. Post-treatment, she developed symptoms including intermittent fever and severe arthralgia. Laboratory tests revealed an elevated white blood cell count, C-reactive protein levels, and erythrocyte sedimentation rate, while a computed tomography scan showed thickening in the aortic arch and descending aorta. Given the clinical presentation and exclusion of other potential causes, pegylated G-CSF-induced aortitis was suspected. The patient's symptoms improved significantly following the cessation of pegylated G-CSF, aiding in the differentiation from other types of aortitis. This study highlights the importance of considering pegylated G-CSF as a potential cause of aortitis in patients presenting with unexplained symptoms of fever and inflammation after chemotherapy. The rapid improvement upon discontinuation of the drug is a key feature distinguishing it from other aortitis causes. In conclusion, while rare, aortitis should be considered in the differential diagnosis of patients treated with pegylated G-CSF who exhibit relevant clinical symptoms. Early detection and management, including the discontinuation of the causative agent, are crucial for patient recovery and prognosis.

Recent trends in organ-preserving pancreatectomy: Its problems and clinical advantages compared with other standard pancreatectomies.

In this review article, we focus on recent papers on organ-preserving pancreatectomy procedures published since 2010. When comparing central pancreatectomy (CP) and distal pancreatectomy (DP), most studies have concluded that the CP group exhibited significantly lower incidence of new-onset diabetes or diabetes exacerbation than the DP group postoperatively. However, because of increased incidence of morbidities such as pancreatic fistula, the surgeon faces a considerable trade-off between increased short-term morbidity and long-term preservation of endocrine function. When the outcomes of two types of spleen-preserving DP (Kimura and Warshaw procedures) are compared, most studies mentioned the low incidence of postoperative gastric varices and splenic infarction with the Kimura procedure. Although there are several reports regarding the effect of spleen preservation on prevention of postoperative infections, no report on the contribution of spleen preservation to the prevention of overwhelming post-splenectomy infection is seen. The advantages of duodenum-preserving pancreatic head resection (DPPHR) concerning endocrine and exocrine functions continue to be subjects of discussion, mainly due to the limited number of institutions that have adopted this approach; however, DPPHR should be presented as an option for patients due to its low incidence of postoperative cholangitis. Organ-preserving pancreatectomy requires meticulous surgical techniques, and postoperative complications may increase with this surgery compared with standard pancreatectomy, which may be influenced by the surgeon's skill and the surgical facility where the procedure is performed. Nonetheless, this technique has significant long-term advantages in terms of endocrine and exocrine functions and its wider adoption in the future is expected.

Effect of Recent Antirheumatic Drug on Features of Rheumatoid Arthritis-Associated Lymphoproliferative Disorders.

OBJECTIVE: In this study, we examine how advancements in novel antirheumatic drugs affect the clinicopathologic features of lymphoproliferative disorder (LPD) in patients with rheumatoid arthritis (RA). METHODS: In this multicenter study across 53 hospitals in Japan, we characterized patients with RA who developed LPDs and visited the hospitals between January 1999 and March 2021. The statistical tools used included Fisher's exact test, the Mann-Whitney U-test, the log-rank test, logistic regression analysis, and Cox proportional hazards models. RESULTS: Overall, 752 patients with RA-associated LPD (RA-LPD) and 770 with sporadic LPD were included in the study. We observed significant differences in the clinicopathologic features between patients with RA-LPD and those with sporadic LPD. Histopathological analysis revealed a high frequency of LPD-associated immunosuppressive conditions. Furthermore, patients with RA-LPD were evaluated based on the antirheumatic drugs administered. The methotrexate (MTX) plus tacrolimus and MTX plus tumor necrosis factor inhibitor (TNFi) groups had different affected site frequencies and histologic subtypes than the MTX-only group. Moreover, MTX and TNFi may synergistically affect susceptibility to Epstein-Barr virus infection. In case of antirheumatic drugs administered after LPD onset, tocilizumab (TCZ)-only therapy was associated with lower frequency of regrowth after spontaneous regression than other regimens. CONCLUSION: Antirheumatic drugs administered before LPD onset may influence the clinicopathologic features of RA-LPD, with patterns changing over time. Furthermore, TCZ-only regimens are recommended after LPD onset.

PD-L1-negative Non-small-cell Lung Cancer Treated with Nivolumab Plus Ipilimumab during Maintenance Hemodialysis Results in Rapid Initial Progression Followed by a Long-lasting Response.

Nivolumab plus ipilimumab is one of the first-line treatments for advanced non-small-cell lung cancer (NSCLC), but the safety and efficacy in patients on hemodialysis (HD) is unclear. We herein report a patient with NSCLC on HD in whom nivolumab and ipilimumab were initiated. We observed general deterioration and enlarged lesions, followed by a long-term response. The patient developed secondary hypoadrenocorticism, an immune-related adverse event that was easily controlled. Nivolumab plus ipilimumab can be used safely for patients with NSCLC on HD. Long-term effectiveness can be observed after initial progression, so we should carefully assess the response.

Prevalence and diagnostic significance of non-invasive follicular thyroid neoplasm with papillary-like nuclear features in Japan-A multi-institutional study.

This multi-institutional study investigated non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) frequency and its diagnostic significance in Japan. We reviewed 4008 thyroid nodules resected in six institutions before NIFTP was proposed. Overall, 26 cases diagnosed as non-invasive encapsulated follicular variant of papillary thyroid carcinoma (PTC) and 145 cases of follicular thyroid adenoma (FTA) were included. Of these nodules, 80.8% and 31.0%, respectively, were NIFTPs. In five institutions, NIFTPs were more commonly found in FTA than in PTC nodules. When NIFTP was included with PTC, the overall prevalence was 2.3%, with rates in five institutions below 5.0% (0.8%-4.4%). One NIFTP case with nuclear score 3 revealed nodal metastasis 2.5 years post-resection, and the carcinoma cells were immunohistochemically positive for BRAF. FTAs or NIFTPs with nuclear score 2 did not metastasize. NIFTP was more common among FTA than among PTC nodules, possibly due to underdiagnosis of PTC on nuclear findings. Considering the clinical findings, molecular pathogenesis, and therapeutic strategy in Japan, NIFTP with nuclear score 2 is not different from FTA, and use of this entity terminology is not meaningful. In contrast, NIFTP with nuclear score 3 has potential for metastasis and BRAFV600E mutation. Therefore, in NIFTP cases, nuclear scores 2 and 3 should be separately reported.

Risk factors for late recurrence and postrelapse survival in estrogen receptor (ER)-positive, human epidermal growth factor receptor (HER) 2-negative breast cancer after 5 years of endocrine therapy.

It is unclear which patients with ER-positive, HER2-negative breast cancer benefit from extended endocrine therapy beyond 5 years. Prognostic factors for late-recurring breast cancer postrelapse survival have been reported. We retrospectively analyzed data from 892 patients with ER-positive and HER2-negative invasive breast cancer who were disease-free after completing a 5-year adjuvant endocrine therapy. Patients were then classified as high-risk (positive lymph nodes, large tumor size, high tumor grade) or low-risk. High-risk patients were divided into extended endocrine therapy and stop groups. Comparisons were made using propensity score matching, and the benefits of extended endocrine therapy for high-risk patients and prognostic factors for postrelapse survival were assessed. The high- and low-risk groups comprised 444 and 448 patients, respectively. The 10-year distant disease-free survival (DDFS) rates were 96.3 % (95 % confidence interval [CI] 0.912-0.985) and 86.5 % (95 % CI 0.798-0911) in the extended and stop groups, respectively (P = 0.00382). Cox proportional hazards model revealed that extended endocrine therapy promoted greater reduction in distant metastasis risk than 5-year endocrine therapy in high-risk populations (hazard ratio [HR] 0.27; 95 % CI 0.11-0.68; P = 0.0054). Postrelapse survival was significantly different in patients with DDFS ≥7 years (HR 0.24; 95 % CI 0.072-0.81; P = 0.021) and those with better response to first-line treatment (HR 0.072; 95 % CI, 0.058-0.90; P = 0.041). Patients with risk factors for late recurrence should be considered for extended endocrine therapy. Longer DDFS and response to first-line treatment may be a prognostic factor for postrelapse survival after late recurrence.

Novel Iron Chelators, Super-Polyphenols, Show Antimicrobial Effects against Cariogenic Streptococcus mutans.

Dental caries are an oral infectious disease that can affect human health both orally and systemically. It remains an urgent issue to establish a novel antibacterial method to prevent oral infection for a healthy life expectancy. The aim of this study was to evaluate the inhibitory effects of novel iron chelators, super-polyphenols (SPs), on the cariogenic bacterium Streptococcus mutans, in vitro. SPs were developed to reduce the side effects of iron chelation therapy and were either water-soluble or insoluble depending on their isoforms. We found that SP6 and SP10 inhibited bacterial growth equivalent to povidone-iodine, and viability tests indicated that their effects were bacteriostatic. These results suggest that SP6 and SP10 have the potential to control oral bacterial infections such as Streptococcus mutans.

Effects of non-technical skill-based surgical education for trainees on herniorrhaphy outcomes.

INTRODUCTION: Non-technical skills are essential for surgical patient safety and are implemented in clinical practice. However, training for non-technical skills has not been thoroughly investigated. This study aimed to evaluate the learning curve for non-technical skill-based education in herniorrhaphy. METHODS: Quality improvement initiatives, including non-technical skill-based intervention, were performed in the department of surgery. The intervention included declaring the patient safety policy, briefing and debriefing, and criterion for the switching of places of the trainee and instructor as defined by the department. Patients who underwent herniorrhaphy from April 2014 to September 2017 were included. RESULTS: A total of 14 trainees and nine instructors in the pre-intervention period and 14 trainees and seven instructors in the intervention period were included in this study. The median experience of each trainee was 28 and 15 cases in the pre-intervention and intervention groups, respectively. A total of 749 patients were included: 473 in the pre-intervention period and 328 in the intervention period. Demographics and hernia types were mostly similar between groups, and morbidity was not statistically different between the two groups (3.4 vs. 1.2%, p = 0.054). The nonlinear regression model showed an early decline and deep plateau phase of the learning curve in the intervention group. A significant difference was observed in the plateau operation time (61 min in the pre-intervention group and 52 min in the intervention group). CONCLUSION: This study demonstrated the effectiveness of non-technical skill-based intervention for surgical training. An early decline and deep plateau of the learning curve can be achieved with well-implemented quality improvement initiatives. Nonetheless, further studies are needed to establish a training program for non-technical skill-based learning.

Collision tumor of a papillary and follicular thyroid carcinoma: a case report.

BACKGROUND: Papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) are common differentiated thyroid cancers, but the detection of a collision tumor is an extremely rare event. CASE PRESENTATION: The patient was a 69-year-old Japanese female with multiple cervical lymph node swellings and a thyroid tumor. Preoperative fine needle aspiration cytology of the enlarged lymph node revealed a cytological diagnosis of papillary thyroid carcinoma (PTC). A total thyroidectomy, right cervical dissection and paratracheal dissection were performed. Histopathological and immunohistochemical analyses of resected specimens revealed a collision tumor of PTC and FTC. Multiple metastases of papillary carcinoma were found in the dissected lymph nodes. In the PTC lesion, IHC for BRAF (V600E) was positive but negative for the FTC lesion. Genetic analyses further revealed a TERT promoter C228T mutation in PTC and a NRAS codon 61 mutation in FTC. The patient died of recurrent cancer 8 months after surgery. CONCLUSIONS: A case of a collision tumor of PTC and FTC is very rare, and even fewer cases have been subjected to genetic scrutiny. The present case was successfully diagnosed by pathological examination using immunohistochemical and genetic analyses. The TERT promoter mutation in the PTC lesion was consistent with the aggressive behavior of the cancer.

[A Case of Locally Advanced, Unresectable Pancreatic Cancer with Superior Mesenteric Artery Invasion Treated with FOLFIRINOX plus Radiation Therapy, followed by Conversion Surgery].

We report a case of a woman in her 70s who underwent conversion surgery after FOLFIRINOX, followed by radiation therapy for initially locally advanced unresectable pancreatic cancer. She visited her local doctor with a chief complaint of upper abdominal pain. Contrast-enhanced CT scan of the abdomen revealed an irregular mass invading the superior mesenteric artery, and the first and second jejunal arteries(>180°)in the pancreatic uncinate region. Based on imaging, she was diagnosed as UR-LA(sm), cT4N0M0, cStage Ⅲ pancreatic cancer, and underwent 5 courses of modified FOLFIRINOX. Radiation therapy of 50.4 Gy was added for local control, and CA19-9 decreased from 394.1 U/mL to 10.5 U/mL. The treatment effect was judged as RECIST: partial response. The tumor was considered to be potentially curative, and a subtotal stomach preserving pancreaticoduodenectomy was performed 8 months after the initial treatment. The tumor was found to be 3× 2 mm in size, pStage ⅠA, R0, and the response to preoperative chemotherapy: Evans Grade Ⅲ. The patient is alive at 5 months postoperatively without recurrence.

[A Case of Local Recurrent Liver Metastasis from Sigmoid Colon Cancer after Complete Histological Remission, Treated with Rehepatectomy].

We report a case of a patient with sigmoid colon cancer and multiple liver metastases who underwent hepatectomy after chemotherapy and pathological results showed complete remission. However, after chemotherapy was discontinued, the patient developed a local recurrence of the liver metastasis and underwent rehepatectomy. The patient came to our hospital with lower abdominal pain. Colonoscopy revealed a circumferential type Ⅱ, well-differentiated adenocarcinoma. Laparoscopic sigmoidectomy with lymph node dissection was performed. Postoperative CT scan showed multiple liver metastases at S5, S7, and S8. 11 cycles of bevacizumab plus modified FOLFOX(mFOLFOX)were subsequently performed. The liver metastases shrank at all sites, and the patient underwent right hepatectomy. The resected specimen was considered to be in complete remission, with no evidence of viable malignant cells. Postoperatively, bevacizumab plus mFOLFOX was resumed for 6 cycles and the patient remained in remission. However, 3 months after stopping chemotherapy and 1 year and 6 months after hepatectomy, a follow-up CT scan showed local recurrence of the liver edge, and a diagnosis of local recurrence of liver metastasis was made, and a partial hepatectomy was performed. The patient is recurrence-free and resuming modified FOLFOX 9 months after surgery.

Optical Filters with Asymmetric Transmittance Depending on the Incident Angle, Produced Using Liquid Crystalline Ink (Louver LC Filters).

In many situations in everyday life, sunlight levels need to be reduced. Optical filters with asymmetric transmittance dependent on the incident angle would be useful for sunglasses and vehicle or architectural windows, among others. Herein, we realized the production of optical filters, called "louver filters", comprising HAN-type LC film produced using liquid crystalline ink with dichroic dyes. For the formation of the HAN-type LC film, the liquid crystalline ink was aligned on a rubbed polyimide layer and polymerized by UV irradiation. Two kinds of filters are proposed: one is a filter composed of HAN-type LC film and a polarizer, and the other is composed of two HAN-LC films with a half-wave plate between them. The dependence of the asymmetric transmittance on the incident angle was confirmed for these filters. The dependence changed depending on the pretilt angle of the alignment layers. Photographs taken with the optical filters displayed their effectiveness.

Novel quinazolin-4(3H)-one based Cyclin K degraders regulate alternative polyadenylation activity.

Phenotypic screening is gaining attention as a powerful method for identifying compounds that regulate cellular phenotypes of interest through novel mechanisms of action. Recently, a new modality of compounds, called molecular glues, which can induce the degradation of target proteins by forming ternary complexes of E3 ligases, has emerged from phenotypic screening. In this study, using global proteomic analysis, we identified a novel Cyclin K degrader, T4, which was previously discovered through phenotypic screening for alternative polyadenylation regulation. Our detailed mechanistic analysis revealed that T4 induced Cyclin K degradation, leading to the regulation of alternative polyadenylation. Additionally, we generated a more potent Cyclin K degrader, TR-213, through a structure-activity relationship study of T4. T4 and TR-213 are structurally distinct from other Cyclin K degraders and can be used as novel chemical tools to further analyze the degradation of Cyclin K and the regulation of alternative polyadenylation.