Objectives: Our purpose was to elucidate the involvement of the tyrosine kinase pathway in gonadotropin-induced ovulation in the rat ovary.
Study Design: We investigated the effect of a tyrosine kinase inhibitor, tyrphostin, on the rat ovulatory process in vivo and in vitro.
Methods: In cultured rat granulosa cells, the effect of tyrphostin on LH-, dibutyryl cyclic AMP ((Bu)2cAMP)- or forskolin-stimulated tissue type plasminogen activator (tPA) activities was examined by using a fibrin autography technique. In an in vivo system, tyrphostin was injected into the bursal cavity of the ovary in pregnant mare serum gonadotropin-treated rats, just before human chorionic gonadotropin administration. After 24 h, the number of oocytes in the oviduct was counted and the tyrphostin-treated ovaries were examined histologically.
Results: Tyrphostin inhibited LH-stimulated tPA activity but did not affect (Bu)2cAMP- or forskolin-stimulated ones. In an in vivo study, tyrphostin suppressed oocyte release dose-dependently. Histological observations revealed that tyrphostin-treated ovaries contained many large unruptured follicles and a few corpora lutea.
Conclusion: This study suggests that the suppressive effect of tyrphostin on ovulation may be partly due to tPA activity inhibition in the granulosa cells via the suppression of tyrosine kinase activity. Additionally, tyrosine kinase phosphorylation may be involved in gonadotropin-activated signaling systems in the rat ovulatory process.
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http://dx.doi.org/10.1530/eje.0.1380594 | DOI Listing |
J Transl Med
January 2025
Department of Hematology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Beijing, 100730, China.
Background: Immunotherapy is a significant risk factor for severe COVID-19 in multiple myeloma (MM) patients. Understanding how immunotherapies lead to severe COVID-19 is crucial for improving patient outcomes.
Methods: Human protein microarrays were used to examine the expression of 440 protein molecules in MM patients treated with bispecific T-cell engagers (BiTe) (n = 9), anti-CD38 monoclonal antibodies (mAbs) (n = 10), and proteasome inhibitor (PI)-based regimens (n = 10).
Biochemistry (Mosc)
December 2024
Medicinal Chemistry Center, Togliatti State University, Togliatti, 445020, Russia.
Human carbonic anhydrase IX (CAIX) plays a key role in maintaining pH homeostasis of malignant neoplasms, thus creating a favorable microenvironment for the growth, invasion, and metastasis of tumor cells. Recent studies have established that inhibition of CAIX expressed on the surface of tumor cells significantly increases the efficacy of classical chemotherapeutic agents and makes it possible to suppress the resistance of tumor cells to chemotherapy, as well as to increase their sensitivity to drugs (in particular, to reduce the required dose of cytostatic agents). In this work, we studied the ability of new CAIX inhibitors based on substituted 1,2,4-oxadiazole-containing primary aromatic sulfonamides, to potentiate the cytostatic effect of gefitinib (selective inhibitor of epidermal growth factor receptor tyrosine kinase domain) under hypoxic conditions.
View Article and Find Full Text PDFBiochemistry (Mosc)
December 2024
Faculty of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia.
The current work presents comparative assessment of affinity of the designed DNA aptamers for extracellular domain of the human epidermal growth factor receptor (EGFR*). The affinity data of the 20 previously published aptamers are summarized. Diversity of the aptamer selection methods and techniques requires unification of the comparison algorithms, which is also necessary for designing aptamers used in the post-selection fitting to the target EGFR* protein.
View Article and Find Full Text PDFZhonghua Yi Xue Za Zhi
January 2025
Department of Medical Oncology, the First Affiliated Hospital of Nanjing Medical University, Nanjing210000, China.
To investigate the impact of SMARCA4 mutations on the outcomes of patients with advanced lung adenocarcinoma with epidermal growth factor receptor (EGFR) mutations. In the Memorial Sloan Kettering Cancer Center (MSK) MetTropism study, 960 patients with advanced EGFR-mutated lung adenocarcinoma were screened and included in the MSK cohort, composing of 313 males and 647 females, with a median [(, )] age of 64 (56, 72) years. A retrospective analysis was conducted on the data of 178 patients with advanced EGFR-mutated lung adenocarcinoma who received EGFR tyrosine kinase inhibitors (TKIs) treatment in the Department of Oncology, the First Affiliated Hospital of Nanjing Medical University, from January 2018 to December 2022.
View Article and Find Full Text PDFJ Thorac Oncol
January 2025
Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL, USA.
Introduction: Amivantamab, an EGFR-MET bispecific antibody, is approved for multiple indications in EGFR-mutated advanced non-small cell lung cancer (NSCLC) as monotherapy or combined with other agents. Intravenous amivantamab is associated with a 67% infusion-related reactions (IRR) rate.
Methods: The phase 2 SKIPPirr study (NCT05663866) enrolled patients with EGFR-mutated (Ex19del/L858R) advanced NSCLC after progression on osimertinib and platinum-based chemotherapy who received intravenous amivantamab plus oral lazertinib (amivantamab-lazertinib), a third-generation tyrosine kinase inhibitor.
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