PI3Kα is protein that regulates key physiological processes such as cell proliferation, survival and metabolism. The function of PI3Kα is jointly regulated by the PIK3CA (encoding the catalytic subunit) and PIK3R1 (encoding the regulatory subunit) genes. Mutations of both genes can lead to abnormal PI3Kα function, thereby causing a variety of diseases.

In the field of cancer, activating mutations or gene amplification of PIK3CA, as well as inactivating mutations or gene deletions of PIK3R1, can lead to overactivation of PI3Kα, promoting the occurrence and development of tumors such as breast cancer, ovarian clear cell carcinoma, and colorectal cancer. Therefore, PI3Kα becomes an important target for cancer targeted therapy.

In addition, activating mutations of PIK3CA or inactivating mutations of PIK3R1 are also associated with the occurrence of various non-tumor diseases, further highlighting the important role of PI3Kα in various diseases.

Ovarian clear cell carcinoma (OCCC) is a rare , highly aggressive subtype of epithelial ovarian cancer. Compared to the more common serous ovarian carcinoma, OCCC exhibit distinct molecular features and has significantly lower response rates to platinum-based chemotherapy. For recurrent OCCC, no standardized treatment regimen exists, and its prognosis for it is markedly worse than that of serous ovarian carcinoma, highlighting a significant unmet clinical need.
Genomic studies have revealed that PIK3CA mutations are highly prevalent in OCCC. These mutations are predominantly enriched in exon 9 (helical domain) and exon 20 (kinase domain), leading to aberrant activation of PI3Kα and its downstream signaling pathways, which drive OCCC tumorigenesis and progression. Therefore, PI3Kα represents a promising therapeutic target for OCCC.

Haihe Biopharma Co., Ltd. is a global, innovation-driven biopharmaceutical company headquartered in China, with operational hubs in the United States and Japan. The company is dedicated to the development of cutting-edge anti-cancer therapies. With fully integrated capabilities spanning drug discovery, development, manufacturing, and commercialization, Haihe Biopharma aims to deliver life-saving treatments to cancer patients around the world and features a globally minded management and R&D team focused on in-house innovation. Currently, Haihe Biopharma has two approved products: Gumarontinib (INN), approved in both China and Japan, and paclitaxel oral solution (RMX3001/DHP107), approved in China, along with a robust pipeline of additional drug candidates. 

Taiho Pharmaceutical, a subsidiary of Otsuka Holdings Co., Ltd. (https://www.otsuka.com/en/), is an R&D-driven specialty pharma focusing on the fields of oncology and immune-related diseases. Its corporate philosophy takes the form of a pledge: “We strive to improve human health and contribute to a society enriched by smiles.” In the field of oncology, in particular, Taiho Pharmaceutical is known as a leading company in Japan for developing innovative medicines for the treatment of cancer, a reputation that is rapidly expanding through their extensive global R&D efforts. In areas other than oncology, as well, the company creates and markets quality products that effectively treat medical conditions and can help improve people’s quality of life. Always putting customers first, Taiho Pharmaceutical also aims to offer consumer healthcare products that support people’s efforts to lead fulfilling and rewarding lives. For more information about Taiho Pharmaceutical, please visit https://www.taiho.co.jp/en/ 

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