Okayama University


Okayama University Medical Research Updates (OU-MRU) Vol.68

June 11, 2019

Source: Okayama University (JAPAN), Public Relations Division
For immediate release: 06 June 2019
Okayama University research: Improving the diagnosis of pancreatic cancer

(Okayama, 06 June) In a recent study published in the Journal of Gastroenterology researchers at Okayama University report a method to identify specific cases of pancreatic cancer.

Pancreatic cancer is one of the most common causes of mortality worldwide. A new class of drugs which combat the condition, immune-checkpoint inhibitors, has recently emerged. Immune-checkpoint inhibitors, such as atezolizumab or avelumab, bind to a protein called as PD-L1 found on the pancreatic cancer cells of certain patients. However, correctly identifying patients with PD-L1 remains a challenge for oncologists. Such a diagnosis can help clinicians identify PD-L1-positive patients so that checkpoint inhibitor therapy can be initiated early-on. Researchers at Okayama University recently investigated a technique to diagnose this subgroup of patients.

A common, minimally-invasive method to diagnose cancer is fine needle aspiration (FNA). FNA is an advanced technique that involves sliding a thin needle through the skin to suck out suspected cancerous tissue, which is subsequently tested in the laboratory for cancer markers. Professor Hiroyuki Okada and Assistant Professor Kazuyuki Matsumoto’s research team sought out to gauge whether FNA is advanced enough to help detect the presence of PD-L1. Cancer patients often undergo surgery to have their cancerous mass removed. The study was conducted on such patients who had also previously undergone FNA for diagnosis. Analyzing surgically-removed cancerous tissues often gives the most accurate depiction of their characteristics. Therefore, the cancerous tissue resected during surgery and during FNA were analyzed under a microscope for the presence or absence of PD-L1, and both results were compared. If a patient’s tissue contained > 5% or >10% of PD-L1, that patient was considered PD-L1 positive. As the results, approximately half of the patients with PD-L1 expression positive and almost all of patients with PD-L1 expression negative could be diagnosed on FNA specimens.

This study reports the usefulness of identifying PD-L1 at the time of diagnosis of pancreatic cancer and shows that FNA can prove to be a useful method in facilitating this diagnosis. “These results have potential utility in the field of precision medicine for patients with pancreatic cancer”, conclude the researchers. Such an accurate diagnosis, if performed early on, can help oncologists provide customized treatment to patients and greatly improve their chances of survival.

The PD-1–PD-L1 axis: PD-1 is a protein found on T-cells, or the safe-keeping cells, in the human body. Normal cells in the body express a protein called as PD-L1, which binds to PD-1 and deactivates the T-cells. Several types of cancer cells have also devised a mechanism to express PD-L1, thereby bypassing the surveillance of T-cells and safeguarding themselves from attack. Drugs such as checkpoint inhibitors can deactivate the PD-L1 protein so that the cancer cells are not safe anymore.

Kazuyuki Matsumoto, Toshiaki Ohara, Masayoshi Fujisawa, Akinobu Takaki, Masahiro Takahara, Noriyuki Tanaka, Hironari Kato, Shigeru Horiguchi, Ryuichi Yoshida, Yuzo Umeda, Soichiro Fushimi, Takahito Yagi, Akihiro Matsukawa, Hiroyuki Okada. The relationship between the PD-L1 expression of surgically resected and fine-needle aspiration specimens for patients with pancreatic cancer. Journal of Gastroenterology, 2019 Apr 29.
DOI : 10.1007/s00535-019-01586-6.

Correspondence to
Assistant Professor Kazuyuki Matsumoto, M.D., Ph.D.
Department of Gastroenterology and Hepatology,
Okayama University Graduate School of Medicine,
Dentistry, and Pharmaceutical Sciences, 2-5-1,
Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
E-mail: matsumoto.k(a)okayama-u.ac.jp
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Okayama University Medical Research Updates (OU-MRU)
The whole volume : OU-MRU (1- )
Vol.1:Innovative non-invasive ‘liquid biopsy’ method to capture circulating tumor cells from blood samples for genetic testing
Vol.2:Ensuring a cool recovery from cardiac arrest
Vol.3:Organ regeneration research leaps forward
Vol.4:Cardiac mechanosensitive integrator
Vol.5:Cell injections get to the heart of congenital defects
Vol.6:Fourth key molecule identified in bone development
Vol.7:Anticancer virus solution provides an alternative to surgery
Vol.8:Light-responsive dye stimulates sight in genetically blind patients
Vol.9:Diabetes drug helps towards immunity against cancer
Vol.10:Enzyme-inhibitors treat drug-resistant epilepsy
Vol.11:Compound-protein combination shows promise for arthritis treatment
Vol.12:Molecular features of the circadian clock system in fruit flies
Vol.13:Peptide directs artificial tissue growth
Vol.14:Simplified boron compound may treat brain tumours
Vol.15:Metamaterial absorbers for infrared inspection technologies
Vol.16:Epigenetics research traces how crickets restore lost limbs
Vol.17:Cell research shows pathway for suppressing hepatitis B virus
Vol.18:Therapeutic protein targets liver disease
Vol.19:Study links signalling protein to osteoarthritis
Vol.20:Lack of enzyme promotes fatty liver disease in thin patients
Vol.21:Combined gene transduction and light therapy targets gastric cancer
Vol.22:Medical supportive device for hemodialysis catheter puncture
Vol.23:Development of low cost oral inactivated vaccines for dysentery
Vol.24:Sticky molecules to tackle obesity and diabetes
Vol.25:Self-administered aroma foot massage may reduce symptoms of anxiety
Vol.26:Protein for preventing heart failure
Vol.27:Keeping cells in shape to fight sepsis
Vol.28:Viral-based therapy for bone cancer
Vol.29:Photoreactive compound allows protein synthesis control with light
Vol.30:Cancer stem cells’ role in tumor growth revealed
Vol.31:Prevention of RNA virus replication
Vol.32:Enzyme target for slowing bladder cancer invasion
Vol.33:Attacking tumors from the inside
Vol.34:Novel mouse model for studying pancreatic cancer
Vol.35:Potential cause of Lafora disease revealed
Vol.36:Overloading of protein localization triggers cellular defects
Vol.37:Protein dosage compensation mechanism unravelled
Vol.38:Bioengineered tooth restoration in a large mammal
Vol.39:Successful test of retinal prosthesis implanted in rats
Vol.40:Antibodies prolong seizure latency in epileptic mice
Vol.41:Inorganic biomaterials for soft-tissue adhesion
Vol.42:Potential drug for treating chronic pain with few side effects
Vol.43:Potential origin of cancer-associated cells revealed
Vol.44:Protection from plant extracts
Vol.45:Link between biological-clock disturbance and brain dysfunction uncovered
Vol.46:New method for suppressing lung cancer oncogene
Vol.47:Candidate genes for eye misalignment identified
Vol.48:Nanotechnology-based approach to cancer virotherapy
Vol.49:Cell membrane as material for bone formation
Vol.50:Iron removal as a potential cancer therapy
Vol.51:Potential of 3D nanoenvironments for experimental cancer
Vol.52:A protein found on the surface of cells plays an integral role in tumor growth and sustenance
Vol.53:Successful implantation and testing of retinal prosthesis in monkey eyes with retinal degeneration
Vol.54:Measuring ion concentration in solutions for clinical and environmental research
Vol.55:Diabetic kidney disease: new biomarkers improve the prediction of the renal prognosis
Vol.56:New device for assisting accurate hemodialysis catheter placement
Vol.57:Possible link between excess chewing muscle activity and dental disease
Vol.58:Insights into mechanisms governing the resistance to the anti-cancer medication cetuximab
Vol.59:Role of commensal flora in periodontal immune response investigated
Vol.60:Role of commensal microbiota in bone remodeling
Vol.61:Mechanical stress affects normal bone development
Vol.62:3D tissue model offers insights into treating pancreatic cancer
Vol.63:Promising biomarker for vascular disease relapse revealed
Vol.64:Inflammation in the brain enhances the side-effects of hypnotic medication
Vol.65:Game changer: How do bacteria play Tag ?
Vol.66:Is too much protein a bad thing?
Vol.67:Technology to rapidly detect cancer markers for cancer diagnosis